Chronic total occlusions: Difference between revisions

Jump to navigation Jump to search
 
(20 intermediate revisions by 3 users not shown)
Line 1: Line 1:
__NOTOC__
__NOTOC__
{{PCI}}
{{PCI}}
{{CMG}}; '''Associate Editors-In-Chief:''' Duane Pinto, M.D.; Brian C. Bigelow, M.D.; Roger J. Laham, M.D.; Randall K. Harada, M.D.
{{CMG}}; '''Associate Editors-In-Chief:''' Duane Pinto, M.D.; Brian C. Bigelow, M.D.; Roger J. Laham, M.D.; Randall K. Harada, M.D.{{Cherry}} {{Anahita}}
 
<small>'''[[Percutaneous Transluminal Coronary Angioplasty of a Left Main Chronic Total Occlusion in a Retrograde Approach via a Saphenous Vein Graft with Impella Support|Click here]] to see a case of chronic total occlusion with retrograde approach on [[Tweetbook: Cardiovascular Interventions|Tweetbook.]]</small>


==Overview==
==Overview==
Chronic total occlusions (CTO) are often defined as [[coronary artery|coronary]] occlusions that have had [[TIMI]] 0 or 1 flow for an estimated duration of at least one month. [[Collateral]] flow to the [[distal]] territory maintains viability, but may be insufficient at times of increased oxygen demand, resulting in [[chronic stable angina]] or reduced [[exercise capacity]]. The [[tissue]] composition of the CTO is a variable mix of [[collagen]]-rich [[plaque]], layered [[thrombus]], [[calcium]], and [[inflammatory]] cells with [[fibrin|fibro]]-[[calcification|calcific]] caps at both ends. [[Neovascularization]] channels may form a neo-[[lumen]] or connect with [[adventitial]] [[vasa vasorum]]. The latter type of channels and bridging [[collateral]]s reduce the likelihood of successful [[guidewire]] advancement. [[PCI|Percutaneous interventions]] of CTO remain a technical challenge.   
[[Chronic total occlusions]] ([[Chronic total occlusions|CTO]]) are often defined as [[coronary artery|coronary]] occlusions that have had [[TIMI]] 0 or 1 flow for an estimated duration of at least one month. [[Collateral]] flow to the [[distal]] territory maintains viability, but may be insufficient at times of increased [[oxygen]] demand, resulting in [[chronic stable angina]] or reduced [[exercise capacity]]. The [[tissue]] composition of the [[Chronic total occlusions|CTO]] is a variable mix of [[collagen]]-rich [[plaque]], layered [[thrombus]], [[calcium]], and [[inflammatory]] cells with [[fibrin|fibro]]-[[calcification|calcific]] caps at both ends. [[Neovascularization]] channels may form a neo-[[lumen]] or connect with [[adventitial]] [[vasa vasorum]]. The latter type of channels and bridging [[collateral]]s reduce the likelihood of successful [[guidewire]] advancement. [[PCI|Percutaneous interventions]] of [[Chronic total occlusions|CTO]] remain a technical challenge.
== Goals of Treatment ==
==Epidemiology and Demographics==
*One-quarter of [[patients]] undergoing [[coronary angiography]] has [[CTO]].<ref name="pmid22402070">{{cite journal| author=Fefer P, Knudtson ML, Cheema AN, Galbraith PD, Osherov AB, Yalonetsky S | display-authors=etal| title=Current perspectives on coronary chronic total occlusions: the Canadian Multicenter Chronic Total Occlusions Registry. | journal=J Am Coll Cardiol | year= 2012 | volume= 59 | issue= 11 | pages= 991-7 | pmid=22402070 | doi=10.1016/j.jacc.2011.12.007 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=22402070  }} </ref><ref name="pmid28473108">{{cite journal| author=Tsai TT, Stanislawski MA, Shunk KA, Armstrong EJ, Grunwald GK, Schob AH | display-authors=etal| title=Contemporary Incidence, Management, and Long-Term Outcomes of Percutaneous Coronary Interventions for Chronic Coronary Artery Total Occlusions: Insights From the VA CART Program. | journal=JACC Cardiovasc Interv | year= 2017 | volume= 10 | issue= 9 | pages= 866-875 | pmid=28473108 | doi=10.1016/j.jcin.2017.02.044 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=28473108 }} </ref>
==Rentrop Grade of Collateral Filling==
Rentrop classification is helpful to define the collateral circulation of [[Chronic total occlusions|CTO]]. Rentrop ''et al.'' proposed the system below to grade collateral filling of recipient arteries:<ref>{{Cite journal | issn = 0735-1097 | volume = 5 | issue = 3 | pages = 587–592 | last = Rentrop | first = K. P. | coauthors = M. Cohen, H. Blanke, R. A. Phillips | title = Changes in collateral channel filling immediately after controlled coronary artery occlusion by an angioplasty balloon in human subjects | journal = Journal of the American College of Cardiology | date = 1985-03 | pmid = 3156171 }}</ref>
 
====Rentrop Grade 0====
No visible filling of any collateral channels.
 
====Rentrop Grade 1====
Collateral filling of branches of the [[vessel]] to be dilated without any dye reaching the [[epicardial]] segment of that [[vessel]] (ie, [[right coronary artery]] [[Injection (medicine)|injection]] showing retrograde filling of septal branches to their origin from the [[left anterior descending artery]], without visualization of the latter occluded [[artery]]).
 
====Rentrop Grade 2====
Partial collateral filling of the [[epicardial]] segment of the [[vessel]] being dilated.
 
====Rentrop Grade 3====
Complete collateral filling of the [[Blood vessel|vessel]] being dilated.
 
<!--
{| style="border: 0px; font-size: 90%; margin: 0px;"
| style="background: #4479BA; font-weight: bold; font-style: italic; color: #FFFFFF; padding: 5px 5px;" align=center | Rentrop Grade
| style="background: #4479BA; font-weight: bold; font-style: italic; color: #FFFFFF; padding: 5px 5px;" align=center | Description
|-
| style="background: #DCDCDC; font-weight: bold; padding: 5px 5px;" align=center | 0
| style="background: #F0F0F0; padding: 5px 5px;" | No visible filling of any collateral channels.
|-
| style="background: #DCDCDC; font-weight: bold; padding: 5px 5px;" align=center | 1
| style="background: #F0F0F0; padding: 5px 5px;" | Collateral filling of branches of the [[Blood vessel|vessel]] to be dilated without any dye reaching the [[epicardial]] segment of that [[Blood vessel|vessel]]. <BR> (ie, [[right coronary artery]] [[injection]] showing retrograde filling of septal branches to their origin from the [[left anterior descending artery]], without visualization of the latter occluded [[artery]])
|-
| style="background: #DCDCDC; font-weight: bold; padding: 5px 5px;" align=center | 2
| style="background: #F0F0F0; padding: 5px 5px;" | Partial collateral filling of the [[epicardial]] segment of the [[Blood vessel|vessel]] being dilated.
|-
| style="background: #DCDCDC; font-weight: bold; padding: 5px 5px;" align=center | 3
| style="background: #F0F0F0; padding: 5px 5px;" | Complete collateral filling of the [[Blood vessel|vessel]] being dilated.
|}
-->
==Treatment ==
=== Goals of Treatment ===
* Restoration of [[epicardial]] and [[myocardial]] [[perfusion]] in [[acute]] total occlusion
* Restoration of [[epicardial]] and [[myocardial]] [[perfusion]] in [[acute]] total occlusion
* Improvement of functional status  
* Improvement of functional status  
* Improving [[angina]]l status: [[collaterals]] may maintain viability but [[collateral]] insufficiency may lead to [[angina]] symptoms during times of increased [[myocardial]] demand  
* Improving [[angina]]l status: [[collaterals]] may maintain viability but [[collateral]] insufficiency may lead to [[angina]] [[symptoms]] during times of increased [[myocardial]] demand  
* Increasing [[exercise capacity]]
* Increasing [[exercise capacity]]
* Reduced need for late [[bypass surgery]]  
* Reduced need for late [[bypass surgery]]  
Line 15: Line 53:
* Possible benefit of [[PCI]] on [[heart failure]], [[ventricular]] function, and long-term survival
* Possible benefit of [[PCI]] on [[heart failure]], [[ventricular]] function, and long-term survival


==Treatment Choices==
===Treatment Choices===
There are three main treatment choices for CTO:
There are three main [[treatment]] choices for [[CTO]]:
*Medical [[Therapy]]
*Medical [[Therapy]]
*[[PCI|Percutaneous revascularization]]
*[[PCI|Percutaneous revascularization]]
*[[CABG|Surgical revascularization]]
*[[CABG|Surgical revascularization]]


==Medical Therapy==
===Medical Therapy===
All patients should receive optimal medical [[therapy|therapies]] to reduce [[angina]] and [[cardiovascular]] (CV) event risk. [[Revascularization]] attempts may be considered for patients refractory to [[antianginal]] agents.
All [[patients]] should receive optimal medical [[therapy|therapies]] to reduce [[angina]] and [[cardiovascular]] events. [[Revascularization]] attempts may be considered for [[patients]] refractory to [[antianginal]] agents.


==Percutaneous Revascularization==
===Percutaneous Revascularization===
* [[Observational studies]], including TOAST-GISE, showed an association between successful PCI of CTO and higher freedom from [[angina]], [[exercise test]]ing performance, and adjusted survival-free rates from adverse [[cardiovascular]] events.<ref name="pmid12767645">{{cite journal |author=Olivari Z, Rubartelli P, Piscione F, ''et al.'' |title=Immediate results and one-year clinical outcome after percutaneous coronary interventions in chronic total occlusions: data from a multicenter, prospective, observational study (TOAST-GISE) |journal=J. Am. Coll. Cardiol. |volume=41 |issue=10 |pages=1672–8 |year=2003 |month=May |pmid=12767645 |doi= |url=}}</ref>
*[[Observational studies]], including TOAST-GISE, showed an association between successful [[PCI]] of [[CTO]] and higher freedom from [[angina]], [[exercise test]]ing performance, and adjusted survival-free rates from adverse [[cardiovascular]] events.<ref name="pmid12767645">{{cite journal |author=Olivari Z, Rubartelli P, Piscione F, ''et al.'' |title=Immediate results and one-year clinical outcome after percutaneous coronary interventions in chronic total occlusions: data from a multicenter, prospective, observational study (TOAST-GISE) |journal=J. Am. Coll. Cardiol. |volume=41 |issue=10 |pages=1672–8 |year=2003 |month=May |pmid=12767645 |doi= |url=}}</ref>
* Successful PCI of CTO have resulted in improved [[left ventricular ejection fraction]] on serial examinations, though parallel groups of medically treated only patients were not included in these studies. Long-term patency of successful [[angioplasty]] alone is poor; it is improved with the use of [[DES|drug-eluting stents (DES)]].  
*Successful [[PCI]] of [[CTO]] has resulted in improved [[left ventricular ejection fraction]] on serial examinations, though parallel groups of only medically treated [[patients]] were not included in these studies. Long-term patency of successful [[angioplasty]] alone is poor; it is improved with the use of [[DES|drug-eluting stents (DES)]].  
* The [[randomized controlled trial|randomized trial]], PRISON II, showed a superiority of a [[DES]] over a [[bare-metal stent]] for CTO interventions in adverse clinical events, in-[[stent]] late loss, and re-occlusion.<ref name="pmid19081412">{{cite journal |author=Rahel BM, Laarman GJ, Kelder JC, Ten Berg JM, Suttorp MJ |title=Three-year clinical outcome after primary stenting of totally occluded native coronary arteries: a randomized comparison of bare-metal stent implantation with sirolimus-eluting stent implantation for the treatment of total coronary occlusions (Primary Stenting of Totally Occluded Native Coronary Arteries [PRISON] II study) |journal=Am. Heart J. |volume=157 |issue=1 |pages=149–55 |year=2009 |month=January |pmid=19081412 |doi=10.1016/j.ahj.2008.08.025 |url=}}</ref>
*The [[randomized controlled trial|randomized trial]], PRISON II, showed a superiority of a [[DES]] over a [[bare-metal stent]] for [[CTO]] interventions in adverse clinical events, in-[[stent]] late loss, and re-occlusion.<ref name="pmid19081412">{{cite journal |author=Rahel BM, Laarman GJ, Kelder JC, Ten Berg JM, Suttorp MJ |title=Three-year clinical outcome after primary stenting of totally occluded native coronary arteries: a randomized comparison of bare-metal stent implantation with sirolimus-eluting stent implantation for the treatment of total coronary occlusions (Primary Stenting of Totally Occluded Native Coronary Arteries [PRISON] II study) |journal=Am. Heart J. |volume=157 |issue=1 |pages=149–55 |year=2009 |month=January |pmid=19081412 |doi=10.1016/j.ahj.2008.08.025 |url=}}</ref>


==Surgical Revascularization==
===Surgical Revascularization===
* [[CABG|Coronary artery bypass surgery (CABG)]] may be preferable for occluded vessels in patients with higher risk features, such as low [[LV ejection fraction]], [[diabetes mellitus]], or multi-vessel, [[LMCA|left main]], or high-complexity disease.
*[[CABG|Coronary artery bypass surgery (CABG)]] may be preferable for occluded [[vessels]] in [[patients]] with higher risk features, such as low [[LV ejection fraction]], [[diabetes mellitus]], or multi-[[vessel]], [[LMCA|left main]], or high-complexity [[disease]].


==Patient selection==
===Patient selection===
[[Contraindications]] to treatment include:  
[[Contraindications]] to treatment include:  
* Small area of [[myocardial]] viability
*Small area of [[myocardial]] viability
:*Techniques to assess viability prior to the procedure include:
:*Techniques to assess viability prior to the procedure include:
::*Low dose [[Dobutamine]] [[echocardiography]]
::*Low dose [[Dobutamine]] [[echocardiography]]
::* Delayed-enhancement [[Cardiovascular Magnetic Resonance Imaging (CMR)|cardiac magnetic resonance]]
::*Delayed-enhancement [[Cardiovascular Magnetic Resonance Imaging (CMR)|cardiac magnetic resonance]]
::* Thalium/Myoview [[PET|PET scanning]]
::*Thalium/Myoview [[PET|PET scanning]]
* Absence of [[ischemia]]
*Absence of [[ischemia]]
* Low likelihood of procedural success based on [[angiographic]] predictors (failed intervention patients tend to have higher [[mortality]] but also higher procedural [[complication]] rate such as [[coronary artery perforation]]s and [[coronary dissection]]s)
*Low likelihood of procedural success based on [[angiographic]] predictors (failed intervention [[patients]] tend to have higher [[mortality]] but also higher procedural [[complication]] rate such as [[coronary artery perforation]]s and [[coronary dissection]]s)


Clinical predictors of success are very poor. [[Angiographic]] predictors of failure include:  
Clinical predictors of success are very poor. [[Angiographic]] predictors of failure include:  
Line 53: Line 91:
* The presence of a side branch at the occlusion site (the wire may selectively want to enter this rather than the total occlusion)
* The presence of a side branch at the occlusion site (the wire may selectively want to enter this rather than the total occlusion)


These predictors may also be assessed with [[CT angiography|CT]], especially occlusion length. [[CT angiography]] may aid in choosing retrograde approach via [[collaterals]] (CART and reverse CART technique) rather than the traditional antegrade approach.
These predictors may also be assessed with [[CT angiography|CT]], especially occlusion length. [[CT angiography]] may aid in choosing a retrograde approach via [[collaterals]] (CART and reverse CART technique) rather than the traditional antegrade approach.


==PCI Techniques==
===PCI Techniques===
The potential for [[vessel]] perforation during the procedure should be kept in mind in selecting [[antiplatelet]] agents. Pre-treatment with [[aspirin]] may be used in preparation for possible [[stent]] implantation. Some operators wait to administer a [[thienopyridine]] until the procedure is completed without [[vessel]] perforation. [[Heparin]] and a short-acting [[glycoprotein IIb/IIIa inhibitors]] are favored in case of severe [[artery|arterial]] injury requiring [[anticoagulation]] reversal. A strategy of [[heparin]] with a low target [[Activated clotting time|activated clotting time (ACT)]], followed by supplemental [[heparin]], and [[glycoprotein IIb/IIIa inhibitor]] to be administered only after successful [[guidewire]] crossing, may be employed.
*EURO CTO, a [[Clinical trial|randomized multicentre trial]], demonstrated that [[PCI]] of a [[CTO]] is more effective to reduce [[angina]] frequency than optimal [[medication|medical therapy]].<ref name="pmid34895950">{{cite journal| author=Writing Committee Members. Lawton JS, Tamis-Holland JE, Bangalore S, Bates ER, Beckie TM | display-authors=etal| title=2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. | journal=J Am Coll Cardiol | year= 2022 | volume= 79 | issue= 2 | pages= e21-e129 | pmid=34895950 | doi=10.1016/j.jacc.2021.09.006 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=34895950  }} </ref><ref name="pmid29722796">{{cite journal| author=Werner GS, Martin-Yuste V, Hildick-Smith D, Boudou N, Sianos G, Gelev V | display-authors=etal| title=A randomized multicentre trial to compare revascularization with optimal medical therapy for the treatment of chronic total coronary occlusions. | journal=Eur Heart J | year= 2018 | volume= 39 | issue= 26 | pages= 2484-2493 | pmid=29722796 | doi=10.1093/eurheartj/ehy220 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=29722796  }} </ref> While another larger [[Clinical trial|trial]], the DECISION-CTO, showed no significant difference among these two [[treatment]].<ref name="pmid30813758">{{cite journal| author=Lee SW, Lee PH, Ahn JM, Park DW, Yun SC, Han S | display-authors=etal| title=Randomized Trial Evaluating Percutaneous Coronary Intervention for the Treatment of Chronic Total Occlusion. | journal=Circulation | year= 2019 | volume= 139 | issue= 14 | pages= 1674-1683 | pmid=30813758 | doi=10.1161/CIRCULATIONAHA.118.031313 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=30813758  }} </ref>
*The potential for [[vessel]] perforation during the procedure should be kept in mind in selecting [[antiplatelet]] agents.  
*Pre-[[treatment]] with [[aspirin]] may be used in preparation for possible [[stent]] implantation.  
*Some operators wait to administer a [[thienopyridine]] until the procedure is completed without [[vessel]] perforation.  
*[[Heparin]] and a short-acting [[glycoprotein IIb/IIIa inhibitors]] are favored in case of severe [[artery|arterial]] injury requiring [[anticoagulation]] reversal. A strategy of [[heparin]] with a low target [[Activated clotting time|activated clotting time (ACT)]], followed by supplemental [[heparin]], and [[glycoprotein IIb/IIIa inhibitor]] to be administered only after successful [[guidewire]] crossing, may be employed.


===Arterial Access and Guide Catheter Selection===
[[Contralateral]]/ double [[coronary artery|coronary]] [[injection]] from a second catheter, and [[artery|arterial]] access to fill the [[distal]] [[vessel]] bed via [[collaterals]], may be useful for [[angiographic]] guidance of the [[distal]] wire.


Greater support is often required for CTO interventions, and good guiding catheter support may facilitate both wire and balloon passage. For the [[right coronary artery]], a left or right Amplatz guiding catheter can provide excellent coaxial support. A guide with sideholes is often helpful in dilating the [[right coronary artery]]. Extra backup (EBU or XB) guides are useful for the [[left coronary artery|left coronary system]]. Consideration should be given to the use of 7-8 Fr guide sizes to accommodate extra equipment that may be needed. Further back-up support could be provided by larger caliber guide catheters (7 or 8 French).
====Arterial Access and Guide Catheter Selection====
[[Contralateral]]/ double [[coronary artery|coronary]] [[injection]] from a second [[catheter]], and [[artery|arterial]] access to fill the [[distal]] [[vessel]] bed via [[collaterals]], may be useful for [[angiographic]] guidance of the [[distal]] wire.


===Crossing The Lesion With The Wire===
Greater support is often required for [[CTO]] interventions, and good guiding [[catheter]] support may facilitate both wire and balloon passage. For the [[right coronary artery]], a left or right Amplatz guiding [[catheter]] can provide excellent coaxial support. A guide with side holes is often helpful in dilating the [[right coronary artery]]. Extra backup (EBU or XB) guides are useful for the [[left coronary artery|left coronary system]]. Consideration should be given to the use of 7-8 Fr guide sizes to accommodate extra equipment that may be needed. Further backup support could be provided by a larger caliber guide [[catheters]] (7 or 8 French).
 
====Crossing The Lesion With The Wire====
There are several potential choices for crossing a total occlusion. One standard progression in technique might include the following:
There are several potential choices for crossing a total occlusion. One standard progression in technique might include the following:
#Begin with a conventional softer tipped, less traumatic [[guidewire]] as a first step, before progressing to stiffer wires for occlusions with tougher caps. A conventional [[guidewire]] crosses > 90% of [[acute]] (< 3 month old) total occlusions.
#Begin with a conventional softer tipped, less traumatic [[guidewire]] as a first step, before progressing to stiffer wires for occlusions with tougher caps. A conventional [[guidewire]] crosses > 90% of [[acute]] (< 3 month old) total occlusions.
#Several dedicated wires of graded stiffness were developed for CTO crossing, and a successful crossing frequently requires trials of multiple different wires.
#Several dedicated wires of graded stiffness were developed for [[CTO]] crossing, and a successful crossing frequently require trials of multiple different wires.
:* Non-[[hydrophilic]] or [[hydrophobic]] wires with an intermediate stiffness are a good first choice as they have a better tactile response, are less likely to lead to a sub[[intima]]l position than a [[hydrophilic]] wire, and may have an additional advantage in their ability to cross the [[proximal]] cap of the occlusion. Choices in this class include the Miracle Bros 3 and the Asahi intermediate wires.
:* Non-[[hydrophilic]] or [[hydrophobic]] wires with an intermediate stiffness are a good first choice as they have a better tactile response, are less likely to lead to a sub[[intimal]] position than a [[hydrophilic]] wire, and may have an additional advantage in their ability to cross the [[proximal]] cap of the occlusion. Choices in this class include the Miracle Bros 3 and the Asahi intermediate wires.
:* [[Hydrophilic]] wires may track better after the [[proximal]] cap of the occlusion has been crossed. [[Hydrophilic]]/coated wires have better maneuverability in [[tortuosity|tortuous]] or [[calcification|calcified]] [[vessel]]s. Intermediate stiffness [[hydrophilic]] wire choices include the [[Choice PT]] XS (Extra Support), the Pilot 50, the Pilot 100 or the PT Graphix.
:* [[Hydrophilic]] wires may track better after the [[proximal]] cap of the occlusion has been crossed. [[Hydrophilic]]/coated wires have better maneuverability in [[tortuosity|tortuous]] or [[calcification|calcified]] [[vessel]]s. Intermediate stiffness [[hydrophilic]] wire choices include the [[Choice PT]] XS (Extra Support), the Pilot 50, the Pilot 100 or the PT Graphix.
:* Shaping the wire tip using a modest angulation is better for blunted stump occlusions.
:* Shaping the wire tip using a modest angulation is better for blunted stump occlusions.
:* A low-profile balloon or exchange catheter adds back-up support for wire penetration of [[fibrin|fibro]]-[[calcification|calcific]] caps and may also be used cautiously for balloon-assisted progression within the occlusion.
:* A low-profile balloon or exchange catheter adds backup support for wire penetration of [[fibrin|fibro]]-[[calcification|calcific]] caps and may also be used cautiously for balloon-assisted progression within the occlusion.
:* Intra-[[lumen|luminal]] position of the wire [[distal]] to the occlusion is suggested by a freely rotating wire tip or [[angiography]] in different views by distal catheter or [[contralateral]] [[injection]]s.
:* Intra-[[lumen|luminal]] position of the wire [[distal]] to the occlusion is suggested by a freely rotating wire tip or [[angiography]] in different views by distal [[catheter]] or [[contralateral]] [[injection]]s.
:* Stiffer wire tips will allow for a greater chance of crossing the [[proximal]] cap of the occlusion at the cost of an increased risk of vessel [[dissection]] or [[perforation]].
:* Stiffer wire tips will allow for a greater chance of crossing the [[proximal]] cap of the occlusion at the cost of an increased risk of the [[vessel]] [[dissection]] or [[perforation]].
::* Stiff non-[[hydrophilic]] wires: The Miracle Bros 6, 9 and 12, Cross-IT, Confienza, Persuader
::* Stiff non-[[hydrophilic]] wires: The Miracle Bros 6, 9, and 12, Cross-IT, Confienza, Persuader
::* Stiff and [[hydrophilic]] (most aggressive): Pilot 200 and Shinobi
::* Stiff and [[hydrophilic]] (most aggressive): Pilot 200 and Shinobi


===Crossing Lesions That Cannot Be Crossed With A Conventional Wire===
====Crossing Lesions That Cannot Be Crossed With A Conventional Wire====
Tapered-tip wires are occasionally better at navigating into a smaller channel than on 0.014” wire. Lasers, vibrational energy, blunt dissection (e.g. Lumend Frontrunner) and [[ultrasound]] catheters have been used with variable success to recanalize chronic total occlusions resistant to standard wires. Fixed wire-balloon systems do not offer the ability to switch out wires and perform [[distal]] [[injection]].
Tapered-tip wires are occasionally better at navigating into a smaller channel than on 0.014” wire. Lasers, vibrational energy, blunt dissection (e.g. Lumend Frontrunner), and [[ultrasound]] catheters have been used with variable success to recanalize [[chronic total occlusions]] resistant to standard wires. Fixed wire-balloon systems do not offer the ability to switch out wires and perform [[distal]] [[injection]].


===Crossing The Lesion With A Balloon===
====Crossing The Lesion With A Balloon====
Once the wire crossed the [[lesion]], the next step is to perform [[angiography]] to confirm that you are [[lumen|intraluminal]] (i.e. that no [[dissection]] is present) and that wire perforation is not present. If dissection and wire perforation are not present, then an attempt is made to cross the [[lesion]] with a balloon. Fixed wire-balloon systems lack track ability and steer ability therefore over-the-wire systems are usually favored. Fixed wire systems may, however, occasionally be useful because their very low profile which may allow passage in some cases in which a conventional over-the-wire system will not cross. Monorail systems inferior to over-the-wire systems in this setting, because of their inferior balloon tracking characteristics, the inability to exchange [[guidewire]]s, and the inability to make a [[distal]] [[injection]] through the central [[lumen]] of the balloon to confirm your position. Often a low profile short over the wire balloon is a good first choice. An example would be a 1.5 mm X 6 mm balloon. Many investigators will remove the wire from the central [[lumen]] of the balloon and perform a [[distal]] [[injection]] at this point to confirm an [[lumen|intraluminal]] location of the balloon. If [[lumen|intraluminal]] [[guidewire]] position cannot be confirmed, balloon inflation should not be performed. If balloon cannot be inserted all the way across [[lesion]], an inflation in [[proximal]] part of [[lesion]] can be performed to favorably alter [[anatomy]] and potentially facilitate eventual crossing. Consider aborting procedure if, despite multiple attempts with various [[guidewire]]s, lesion cannot be crossed or successfully dilated; the risk of dissection or perforation may outweigh benefit.
Once the wire crossed the [[lesion]], the next step is to perform [[angiography]] to confirm that you are [[lumen|intraluminal]] (i.e. that no [[dissection]] is present) and that wire perforation is not present. If dissection and wire perforation are not present, then an attempt is made to cross the [[lesion]] with a balloon. Fixed wire-balloon systems lack trackability and steer ability therefore over-the-wire systems are usually favored. Fixed wire systems may, however, occasionally be useful because of their very low profile which may allow passage in some cases in which a conventional over-the-wire system will not cross. Monorail systems are inferior to over-the-wire systems in this setting, because of their inferior balloon tracking characteristics, the inability to exchange [[guidewire]]s and the inability to make a [[distal]] [[injection]] through the central [[lumen]] of the balloon to confirm your position. Often a low profile short over the wire balloon is a good first choice. An example would be a 1.5 mm X 6 mm balloon. Many investigators will remove the wire from the central [[lumen]] of the balloon and perform a [[distal]] [[injection]] at this point to confirm an [[lumen|intraluminal]] location of the balloon. If [[lumen|intraluminal]] [[guidewire]] position cannot be confirmed, balloon inflation should not be performed. If the balloon cannot be inserted all the way across [[lesion]], inflation in [[proximal]] part of [[lesion]] can be performed to favorably alter [[anatomy]] and potentially facilitate eventual crossing. Consider aborting the procedure if, despite multiple attempts with various [[guidewire]]s, the lesion cannot be crossed or successfully dilated; the risk of dissection or perforation may outweigh the benefit.


===Special Techniques===
====Special Techniques====
If a wire enters a dissection plane, then a second wire may be used (parallel wire technique) to find a different pathway with the first wire serving as a reference or blocking repeat entry into the false [[lumen]]. Also, if a wire favors entering a side-branch near the site of occlusion, then a balloon may be inflated in that side-branch effecting a block to further wire entry.
*If a wire enters a dissection plane, then a second wire may be used (parallel wire technique) to find a different pathway with the first wire serving as a reference or blocking repeat entry into the false [[lumen]]. Also, if a wire favors entering a side branch near the site of occlusion, then a balloon may be inflated in that side branch effecting a block to further wire entry.
*After failed attempts of recanalizing the true [[lumen]], a sub[[intima]]l tracking and re-entry (STAR) technique may be considered. This is more safely performed in the [[RCA]] where major side branches are absent. Retrograde approaches through robust [[collaterals]] from the [[contralateral]] [[vessel]] have been employed with variable success rates.


After failed attempts of recanalizing the true [[lumen]], a sub[[intima]]l tracking and re-entry (STAR) technique may be considered. This is more safely performed in the [[RCA]] where major side branches are absent. Retrograde approaches through robust [[collaterals]] from the [[contralateral]] [[vessel]] have been employed with variable success rates.
====Special Crossing Devices====
 
* Blunt micro-dissection [[catheters]]
===Special Crossing Devices===
* Blunt micro-dissection catheters
* Optical coherence reflectometry guidance of the wire
* Optical coherence reflectometry guidance of the wire
* [[Radiofrequency ablation]], ultrasonic energy, or microscopic oscillations delivered by special catheter/wire systems to penetrate [[fibrin|fibro]]-[[calcification|calcific]] caps
* [[Radiofrequency ablation]], ultrasonic energy, or microscopic oscillations delivered by special [[catheter]]/wire systems to penetrate [[fibrin|fibro]]-[[calcification|calcific]] caps


===Dilation of the Totally Occluded Lesion===
====Dilation of the Totally Occluded Lesion====
Following initial conventional balloon angioplasty of the [[lesion]], [[stent]] placement reduces [[restenosis]], [[revascularization]], and reocclusion rates. Placement of a [[drug eluting stent]] is a rational choice given the high risk of [[restenosis]] with this [[lesion]] type. Given that the [[lesion]] was totally occluded, the occurrence of [[stent thrombosis]] and complete [[reocclusion]], while unfavorable, may not be as dangerous as it would be in an [[artery]] that was patent prior to placement of the [[stent]]. Other dilation techniques include [[rotational atherectomy]] and laser [[debulking]].
Following initial conventional balloon [[angioplasty]] of the [[lesion]], [[stent]] placement reduces [[restenosis]], [[revascularization]], and reocclusion rates. Placement of a [[drug eluting stent]] is a rational choice given the high risk of [[restenosis]] with this [[lesion]] type. Given that the [[lesion]] was totally occluded, the occurrence of [[stent thrombosis]] and complete [[reocclusion]], while unfavorable, may not be as dangerous as it would be in an [[artery]] that was patent prior to placement of the [[stent]]. Other dilation techniques include [[rotational atherectomy]] and laser [[debulking]].
====More Tips====
=====More Tips=====
*Determine duration of occlusion:
*Determine duration of occlusion:
** If duration of occlusion <3 months, standard [[PTCA]] wires are usually sufficient.
**If duration of occlusion <3 months, standard [[PTCA]] wires are usually sufficient.
* Laserwires are rarely used because they are limited to short [[lesion]]s where [[distal]] [[vessel]] can be visualized via [[collateral]]s.
*Laserwires are rarely used because they are limited to short [[lesion]]s where [[distal]] [[vessel]] can be visualized via [[collateral]]s.
* Ball-tipped [[guidewire]]s have not demonstrated clear superiority over conventional wires in [[observational studies|observational]] and [[randomized control trial|randomized trials]].  
*Ball-tipped [[guidewire]]s have not demonstrated clear superiority over conventional wires in [[observational studies|observational]] and [[randomized control trial|randomized trials]].  
* Blunt dissection may be considered if conventional wires fail to cross the occlusion.
*Blunt dissection may be considered if conventional wires fail to cross the occlusion.
* [[Debulking]] [[calcification|calcified]] or rigid [[lesion]]s with [[rotational atherectomy]] can facilitate distal delivery of [[stent]]s or [[PTCA]] balloons.
*[[Debulking]] [[calcification|calcified]] or rigid [[lesion]]s with [[rotational atherectomy]] can facilitate distal delivery of [[stent]]s or [[PTCA]] balloons.
* If there is good collateral flow to the vessel [[distal]] to the [[stenosis]], the use of two catheters for dual [[injection]]s may be considered.
*If there is good collateral flow to the vessel [[distal]] to the [[stenosis]], the use of two [[catheters]] for dual [[injection]]s may be considered.


====Advanced approaches to chronic total occlusions include====
=====Advanced approaches to chronic total occlusions include=====
* Anchor balloon technique Mother-child catheter (5 Fr within an 8 Fr guide)  
* Anchor balloon technique Mother-child catheter (5 Fr within an 8 Fr guide)  
* Parallel wire and seesaw wiring
* Parallel wire and seesaw wiring
Line 111: Line 153:


====Outcomes====  
====Outcomes====  
Success rates of 50-80% have been reported, but may be affected by selection or publication biases. If the occlusion is less than 3 months old, the [[angiographic]] success rate is >90%, while patients with occlusions greater than 3 months old have a success rate of 70% and higher [[acute]] closure rates. The most common reason for failure is the inability to cross the occlusion with a [[guidewire]] (80-90%). Other common reasons for failure are the inability for the balloon to cross the [[lesion]] (15%), and [[lesion]]s cannot be dilated adequately (5%) (>30% residual [[stenosis]]). [[Calcification]]s are often a major obstacle to crossing the [[lesion]].
*The thrity day [[mortality rate]] after [[PCI]] of a [[CTO]] is 1.3%.<ref name="pmid28797429">{{cite journal| author=Sapontis J, Salisbury AC, Yeh RW, Cohen DJ, Hirai T, Lombardi W | display-authors=etal| title=Early Procedural and Health Status Outcomes After Chronic Total Occlusion Angioplasty: A Report From the OPEN-CTO Registry (Outcomes, Patient Health Status, and Efficiency in Chronic Total Occlusion Hybrid Procedures). | journal=JACC Cardiovasc Interv | year= 2017 | volume= 10 | issue= 15 | pages= 1523-1534 | pmid=28797429 | doi=10.1016/j.jcin.2017.05.065 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=28797429  }} </ref>
 
*Success rates of 50-80% have been reported but may be affected by selection or publication biases.  
[[Restenosis]] and [[reocclusion]] rates following successful PCI are higher in CTO compared to non-occlusive [[stenoses]]. These rates are improved with the use of [[DES]]. Successful PCI of CTO is associated with a 50-70% rate reduction of future [[CABG]]. The salient [[complication]] of [[CTO]] [[PCI]] is [[perforation]], which requires a rapid response: [[proximal]] balloon inflation, [[protamine]] administration for [[heparin]] reversal, consideration of a covered [[stent]] placement, and [[pericardiocentesis]], if indicated.
*If the occlusion is less than 3 months old, the [[angiographic]] success rate is >90%, while [[patients]] with occlusions greater than 3 months old have a success rate of 70% and higher [[acute]] closure rates.  
 
*The most common reason for failure is the inability to cross the occlusion with a [[guidewire]] (80-90%). Other common reasons for failure are the inability for the balloon to cross the [[lesion]] (15%), and [[lesion]]s cannot be dilated adequately (5%) (>30% residual [[stenosis]]). [[Calcification]]s are often a major obstacle to crossing the [[lesion]].
Integration of several [[angiographic]] factors helps determine likelihood of success (see above). No single factor should preclude a [[revascularization]] attempt.
*[[Restenosis]] and [[reocclusion]] rates following successful [[PCI]] are higher in [[CTO]] compared to non-occlusive [[stenoses]]. These rates are improved with the use of [[DES]].  
*Successful [[PCI]] of a [[CTO]] is associated with a 50-70% rate reduction of future [[CABG]].  
*The salient [[complication]] of [[CTO]] [[PCI]] is [[perforation]], which occurs in 4.8% of cases.<ref name="pmid28797429">{{cite journal| author=Sapontis J, Salisbury AC, Yeh RW, Cohen DJ, Hirai T, Lombardi W | display-authors=etal| title=Early Procedural and Health Status Outcomes After Chronic Total Occlusion Angioplasty: A Report From the OPEN-CTO Registry (Outcomes, Patient Health Status, and Efficiency in Chronic Total Occlusion Hybrid Procedures). | journal=JACC Cardiovasc Interv | year= 2017 | volume= 10 | issue= 15 | pages= 1523-1534 | pmid=28797429 | doi=10.1016/j.jcin.2017.05.065 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=28797429  }} </ref>
*If [[perforation]] occurs, it requires a rapid response: [[proximal]] balloon inflation, [[protamine]] administration for [[heparin]] reversal, consideration of a covered [[stent]] placement, and [[pericardiocentesis]], if indicated.
*Integration of several [[angiographic]] factors helps determine the likelihood of success (see above). No single factor should preclude a [[revascularization]] attempt.


====Long-term outcomes====
=====Long-term outcomes=====
* Most patients (70%) are [[angina]]-free 1-4 years after successful [[PTCA]].  
* Most [[patients]] (70%) are [[angina]]-free 1-4 years after successful [[PTCA]].  
* [[Revascularization]] may prevent [[ventricular dilation]], and some studies suggest improvement in global [[ventricular function]].
* [[Revascularization]] may prevent [[ventricular dilation]], and some studies suggest improvement in global [[ventricular function]].
* Successful PTCA reduces the need for [[CABG]] by 50-75% but does not reduce total [[mortality]] or late [[MI]].
* Successful PTCA reduces the need for [[CABG]] by 50-75% but does not reduce total [[mortality]] or late [[MI]].
* [[Restenosis]] rates are high (40-75%); [[stent]]s reduce [[restenosis]] rates.
* [[Restenosis]] rates are high (40-75%); [[stent]]s reduce [[restenosis]] rates.


====Trouble-shooting====
=====Trouble-shooting=====
* Difficult [[guidewire]] rotation, difficulty advancing wire or balloon, or [[guidewire]] buckling may signify an extraluminal position of the wire.
* Difficult [[guidewire]] rotation, difficulty advancing wire or balloon, or [[guidewire]] buckling may signify an extraluminal position of the wire.
* [[Lumen|Intraluminal]] positioning of the crossing wire may be verified by [[distal]] [[injection]] through the central [[lumen]] of PTCA balloon or [[distal]] [[injection]] (Ultrafuse) catheter.
* [[Lumen|Intraluminal]] positioning of the crossing wire may be verified by [[distal]] [[injection]] through the central [[lumen]] of PTCA balloon or [[distal]] [[injection]] (Ultrafuse) [[catheter]].
 
====Other Concerns====
The decision to terminate the procedure if [[guidewire]]s fail to cross the occlusion is based on the severity of [[symptom]]s (i.e. [[angina]]) weighed against the risk of more aggressive techniques/devices, [[fluoroscopy]] time, and [[contrast]] load).
 
==2017 ACCF/AHA/SCAI Guidelines for Percutaneous Coronary Intervention==
* Up to 2011, only observational data had indicated the success of [[Percutaneous coronary intervention|PCI]] over OMT (Optimal Medical therapy) in improving [[cardiovascular disease|cardiovascular outcomes]] in patients with [[CTO]].
* However, three major randomized control trials were conducted between 2011-17. They were called EURO-CTO, DECISION-CTO and EXPLORE.<ref name="urlAppropriateness of CTO PCI in Patients With SIHD - American College of Cardiology">{{cite web |url=http://www.acc.org/latest-in-cardiology/articles/2018/01/30/08/11/appropriateness-of-cto-pci-in-patients-with-sihd |title=Appropriateness of CTO PCI in Patients With SIHD - American College of Cardiology |format= |work= |accessdate=}}</ref>
* These trials concluded that [[Percutaneous coronary intervention|PCI]] was non-superior to OMT in [[patients]] with at least 1 [[CTO]].<ref name="urlOptimal Medical Therapy With or Without Stenting For Coronary Chronic Total Occlusion - American College of Cardiology">{{cite web |url=http://www.acc.org/latest-in-cardiology/clinical-trials/2017/03/17/08/40/decision-cto |title=Optimal Medical Therapy With or Without Stenting For Coronary Chronic Total Occlusion - American College of Cardiology |format= |work= |accessdate=}}</ref>
* In 2017, the updated ACC/AATS/AHA/ASE/ASNC/SCAI/SCCT/STS 2017 Appropriate Use Criteria (AUC) for Coronary Revascularization in Patients With Stable Ischemic Heart Disease (SIHD) was characterized by:<ref name="urlAppropriate Use Criteria for Coronary Revascularization in Stable Ischemic Heart Disease - American College of Cardiology">{{cite web |url=http://www.acc.org/latest-in-cardiology/ten-points-to-remember/2017/03/09/22/13/acc-2017-appropriate-use-criteria-for-revascularization-in-sihd |title=Appropriate Use Criteria for Coronary Revascularization in Stable Ischemic Heart Disease - American College of Cardiology |format= |work= |accessdate=}}</ref>


===Other Concerns===
*Elimination of separate criteria for [[CTO]] or [[anatomy]] specific criteria for [[revascularization]]
The decision to terminate the procedure if [[guidewire]]s fail to cross the occlusion is based on the severity of [[symptom]]s (i.e. [[angina]]) weighted against the risk of more aggressive techniques/devices, [[fluoroscopy]] time, and [[contrast]] load.
*Criteria for [[revascularization]] include:
**[[Symptoms]] of the [[patient]]
**Risk of [[ischemia]]
**Use of [[Antianginal|antianginal medications]]


==2011 ACCF/AHA/SCAI Guidelines for Percutaneous Coronary Intervention (DO NOT EDIT)<ref name="pmid22070837">{{cite journal |author=Levine GN, Bates ER, Blankenship JC, Bailey SR, Bittl JA, Cercek B, Chambers CE, Ellis SG, Guyton RA, Hollenberg SM, Khot UN, Lange RA, Mauri L, Mehran R, Moussa ID, Mukherjee D, Nallamothu BK, Ting HH |title=2011 ACCF/AHA/SCAI Guideline for Percutaneous Coronary Intervention: Executive Summary A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines and the Society for Cardiovascular Angiography and Interventions |journal=[[Journal of the American College of Cardiology]] |volume=58 |issue=24|pages=2550–83 |year=2011|month=December|pmid=22070837|doi=10.1016/j.jacc.2011.08.006|url=http://content.onlinejacc.org/cgi/reprint/58/24/2550.pdf|accessdate=2011-12-08|PDF}}</ref>==
==2011 ACCF/AHA/SCAI Guidelines for Percutaneous Coronary Intervention (DO NOT EDIT)<ref name="pmid22070837">{{cite journal |author=Levine GN, Bates ER, Blankenship JC, Bailey SR, Bittl JA, Cercek B, Chambers CE, Ellis SG, Guyton RA, Hollenberg SM, Khot UN, Lange RA, Mauri L, Mehran R, Moussa ID, Mukherjee D, Nallamothu BK, Ting HH |title=2011 ACCF/AHA/SCAI Guideline for Percutaneous Coronary Intervention: Executive Summary A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines and the Society for Cardiovascular Angiography and Interventions |journal=[[Journal of the American College of Cardiology]] |volume=58 |issue=24|pages=2550–83 |year=2011|month=December|pmid=22070837|doi=10.1016/j.jacc.2011.08.006|url=http://content.onlinejacc.org/cgi/reprint/58/24/2550.pdf|accessdate=2011-12-08|PDF}}</ref>==
===Chronic Total Occlusions<ref name="pmid22070837">{{cite journal|author=Levine GN, Bates ER, Blankenship JC, Bailey SR, Bittl JA, Cercek B, Chambers CE, Ellis SG, Guyton RA, Hollenberg SM, Khot UN, Lange RA, Mauri L, Mehran R, Moussa ID, Mukherjee D, Nallamothu BK, Ting HH |title=2011 ACCF/AHA/SCAI Guideline for Percutaneous Coronary Intervention: Executive Summary A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines and the Society for Cardiovascular Angiography and Interventions |journal=[[Journal of the American College of Cardiology]]|volume=58 |issue=24 |pages=2550–83|year=2011|month=December|pmid=22070837|doi=10.1016/j.jacc.2011.08.006|url=http://content.onlinejacc.org/cgi/reprint/58/24/2550.pdf|accessdate=2011-12-08|PDF}}</ref>===
===Chronic Total Occlusions<ref name="pmid22070837">{{cite journal|author=Levine GN, Bates ER, Blankenship JC, Bailey SR, Bittl JA, Cercek B, Chambers CE, Ellis SG, Guyton RA, Hollenberg SM, Khot UN, Lange RA, Mauri L, Mehran R, Moussa ID, Mukherjee D, Nallamothu BK, Ting HH |title=2011 ACCF/AHA/SCAI Guideline for Percutaneous Coronary Intervention: Executive Summary A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines and the Society for Cardiovascular Angiography and Interventions |journal=[[Journal of the American College of Cardiology]]|volume=58 |issue=24 |pages=2550–83|year=2011|month=December|pmid=22070837|doi=10.1016/j.jacc.2011.08.006|url=http://content.onlinejacc.org/cgi/reprint/58/24/2550.pdf|accessdate=2011-12-08|PDF}}</ref>===
 
*In 2011, The AHA assigned a Class IIa recommendation for CTO-PCI.
{| class="wikitable"
{| class="wikitable"
|-
|-
Line 138: Line 196:


|-
|-
| bgcolor="LemonChiffon" |<nowiki>"</nowiki>'''1.''' PCI of a [[Treatment of chronic total occlusions|chronic total occlusion]] in patients with appropriate clinical indications and suitable [[anatomy]] is reasonable when performed by operators with appropriate expertise.<ref name="pmid12767645">{{cite journal |author=Olivari Z, Rubartelli P, Piscione F, Ettori F, Fontanelli A, Salemme L, Giachero C, Di Mario C, Gabrielli G, Spedicato L, Bedogni F |title=Immediate results and one-year clinical outcome after percutaneous coronary interventions in chronic total occlusions: data from a multicenter, prospective, observational study (TOAST-GISE)|journal=[[Journal of the American College of Cardiology]] |volume=41 |issue=10 |pages=1672–8 |year=2003 |month=May|pmid=12767645 |doi=|url=http://linkinghub.elsevier.com/retrieve/pii/S0735109703003127|accessdate=2011-12-15}}</ref><ref name="pmid11499731">{{cite journal|author=Suero JA, Marso SP, Jones PG, Laster SB, Huber KC, Giorgi LV, Johnson WL, Rutherford BD |title=Procedural outcomes and long-term survival among patients undergoing percutaneous coronary intervention of a chronic total occlusion in native coronary arteries: a 20-year experience |journal=[[Journal of the American College of Cardiology]] |volume=38 |issue=2 |pages=409–14 |year=2001 |month=August|pmid=11499731|doi= |url=http://linkinghub.elsevier.com/retrieve/pii/S0735-1097(01)01349-3|accessdate=2011-12-15}}</ref><ref name="pmid18940287">{{cite journal |author=de Labriolle A, Bonello L, Roy P, Lemesle G, Steinberg DH, Xue Z, Kaneshige K, Suddath WO, Satler LF, Kent KM, Pichard AD, Lindsay J, Waksman R |title=Comparison of safety, efficacy, and outcome of successful versus unsuccessful percutaneous coronary intervention in "true" chronic total occlusions|journal=[[The American Journal of Cardiology]] |volume=102 |issue=9|pages=1175–81 |year=2008|month=November |pmid=18940287|doi=10.1016/j.amjcard.2008.06.059|url=http://linkinghub.elsevier.com/retrieve/pii/S0002-9149(08)01148-X|accessdate=2011-12-15}}</ref><ref name="pmid19539251">{{cite journal |author=Rathore S, Matsuo H, Terashima M, Kinoshita Y, Kimura M, Tsuchikane E, Nasu K, Ehara M, Asakura Y, Katoh O, Suzuki T|title=Procedural and in-hospital outcomes after percutaneous coronary intervention for chronic total occlusions of coronary arteries 2002 to 2008: impact of novel guidewire techniques|journal=[[JACC. Cardiovascular Interventions]] |volume=2 |issue=6 |pages=489–97|year=2009|month=June |pmid=19539251|doi=10.1016/j.jcin.2009.04.008|url=http://linkinghub.elsevier.com/retrieve/pii/S1936-8798(09)00260-X|accessdate=2011-12-15}}</ref><ref name="pmid16230504">{{cite journal |author=Stone GW, Reifart NJ, Moussa I, Hoye A, Cox DA, Colombo A, Baim DS, Teirstein PS, Strauss BH, Selmon M, Mintz GS, Katoh O, Mitsudo K, Suzuki T, Tamai H, Grube E, Cannon LA, Kandzari DE, Reisman M, Schwartz RS, Bailey S, Dangas G, Mehran R, Abizaid A, Moses JW, Leon MB, Serruys PW |title=Percutaneous recanalization of chronically occluded coronary arteries: a consensus document: part II |journal=[[Circulation]]|volume=112 |issue=16 |pages=2530–7 |year=2005 |month=October|pmid=16230504|doi=10.1161/CIRCULATIONAHA.105.583716 |url=http://circ.ahajournals.org/cgi/pmidlookup?view=long&pmid=16230504|accessdate=2011-12-15}}</ref> ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: B]])''<nowiki>"</nowiki>
| bgcolor="LemonChiffon" |<nowiki>"</nowiki>'''1.''' PCI of a [[Treatment of chronic total occlusions|chronic total occlusion]] in [[patients]] with appropriate clinical indications and suitable [[anatomy]] is reasonable when performed by operators with appropriate expertise.<ref name="pmid12767645">{{cite journal |author=Olivari Z, Rubartelli P, Piscione F, Ettori F, Fontanelli A, Salemme L, Giachero C, Di Mario C, Gabrielli G, Spedicato L, Bedogni F |title=Immediate results and one-year clinical outcome after percutaneous coronary interventions in chronic total occlusions: data from a multicenter, prospective, observational study (TOAST-GISE)|journal=[[Journal of the American College of Cardiology]] |volume=41 |issue=10 |pages=1672–8 |year=2003 |month=May|pmid=12767645 |doi=|url=http://linkinghub.elsevier.com/retrieve/pii/S0735109703003127|accessdate=2011-12-15}}</ref><ref name="pmid11499731">{{cite journal|author=Suero JA, Marso SP, Jones PG, Laster SB, Huber KC, Giorgi LV, Johnson WL, Rutherford BD |title=Procedural outcomes and long-term survival among patients undergoing percutaneous coronary intervention of a chronic total occlusion in native coronary arteries: a 20-year experience |journal=[[Journal of the American College of Cardiology]] |volume=38 |issue=2 |pages=409–14 |year=2001 |month=August|pmid=11499731|doi= |url=http://linkinghub.elsevier.com/retrieve/pii/S0735-1097(01)01349-3|accessdate=2011-12-15}}</ref><ref name="pmid18940287">{{cite journal |author=de Labriolle A, Bonello L, Roy P, Lemesle G, Steinberg DH, Xue Z, Kaneshige K, Suddath WO, Satler LF, Kent KM, Pichard AD, Lindsay J, Waksman R |title=Comparison of safety, efficacy, and outcome of successful versus unsuccessful percutaneous coronary intervention in "true" chronic total occlusions|journal=[[The American Journal of Cardiology]] |volume=102 |issue=9|pages=1175–81 |year=2008|month=November |pmid=18940287|doi=10.1016/j.amjcard.2008.06.059|url=http://linkinghub.elsevier.com/retrieve/pii/S0002-9149(08)01148-X|accessdate=2011-12-15}}</ref><ref name="pmid19539251">{{cite journal |author=Rathore S, Matsuo H, Terashima M, Kinoshita Y, Kimura M, Tsuchikane E, Nasu K, Ehara M, Asakura Y, Katoh O, Suzuki T|title=Procedural and in-hospital outcomes after percutaneous coronary intervention for chronic total occlusions of coronary arteries 2002 to 2008: impact of novel guidewire techniques|journal=[[JACC. Cardiovascular Interventions]] |volume=2 |issue=6 |pages=489–97|year=2009|month=June |pmid=19539251|doi=10.1016/j.jcin.2009.04.008|url=http://linkinghub.elsevier.com/retrieve/pii/S1936-8798(09)00260-X|accessdate=2011-12-15}}</ref><ref name="pmid16230504">{{cite journal |author=Stone GW, Reifart NJ, Moussa I, Hoye A, Cox DA, Colombo A, Baim DS, Teirstein PS, Strauss BH, Selmon M, Mintz GS, Katoh O, Mitsudo K, Suzuki T, Tamai H, Grube E, Cannon LA, Kandzari DE, Reisman M, Schwartz RS, Bailey S, Dangas G, Mehran R, Abizaid A, Moses JW, Leon MB, Serruys PW |title=Percutaneous recanalization of chronically occluded coronary arteries: a consensus document: part II |journal=[[Circulation]]|volume=112 |issue=16 |pages=2530–7 |year=2005 |month=October|pmid=16230504|doi=10.1161/CIRCULATIONAHA.105.583716 |url=http://circ.ahajournals.org/cgi/pmidlookup?view=long&pmid=16230504|accessdate=2011-12-15}}</ref> ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: B]])''<nowiki>"</nowiki>
|}
|}
 
==2021 ACA Revascularization Guideline==
==2017 ACCF/AHA/SCAI Guidelines for Percutaneous Coronary Intervention==
{|class="wikitable"
ACC/AATS/AHA/ASE/ASNC/SCAI/SCCT/STS 2017 Appropriate Use Criteria (AUC) for Coronary Revascularization in Patients With Stable Ischemic Heart Disease (SIHD) is characterized by:<ref name="urlAppropriate Use Criteria for Coronary Revascularization in Stable Ischemic Heart Disease - American College of Cardiology">{{cite web |url=http://www.acc.org/latest-in-cardiology/ten-points-to-remember/2017/03/09/22/13/acc-2017-appropriate-use-criteria-for-revascularization-in-sihd |title=Appropriate Use Criteria for Coronary Revascularization in Stable Ischemic Heart Disease - American College of Cardiology |format= |work= |accessdate=}}</ref><ref name="urlAppropriate Use Criteria for Coronary Revascularization in Stable Ischemic Heart Disease - American College of Cardiology">{{cite web |url=http://www.acc.org/latest-in-cardiology/ten-points-to-remember/2017/03/09/22/13/acc-2017-appropriate-use-criteria-for-revascularization-in-sihd |title=Appropriate Use Criteria for Coronary Revascularization in Stable Ischemic Heart Disease - American College of Cardiology |format= |work= |accessdate=}}</ref>
|-
*Elimination of separate criteria for CTO or anatomy specific criteria for [[revascularization]]
| colspan="1" style="text-align:center; background:LightGreen"|Class 2b Recommendation, Level of Evidence: B-R<ref name="pmid34895950">{{cite journal| author=Writing Committee Members. Lawton JS, Tamis-Holland JE, Bangalore S, Bates ER, Beckie TM | display-authors=etal| title=2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. | journal=J Am Coll Cardiol | year= 2022 | volume= 79 | issue= 2 | pages= e21-e129 | pmid=34895950 | doi=10.1016/j.jacc.2021.09.006 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=34895950  }} </ref>
*Criteria for [[revascularization]] include:
|-
**Symptoms of the patient
| bgcolor="LightGreen"|After [[treatment]] of non-[[CTO]] [[lesions]] in [[patients]] with refractory [[angina]] on [[medication|medical therapy]], the benefit of [[PCI]] of a [[CTO]] to diminish [[symptoms]] is uncertain
**Risk of [[ischemia]]
|}
**Use of [[Antianginal|antianginal medications]]
*Despite appreciable [[Retrospective cohort study|retrospective]] and registry data proposing some benefits, there is no clear benefit demonstration from [[Prospective cohort study|prospective]] randomized trials.<ref name="pmid31256614">{{cite journal| author=Abo-Aly M, Misumida N, Backer N, ElKholey K, Kim SM, Ogunbayo GO | display-authors=etal| title=Percutaneous Coronary Intervention With Drug-Eluting Stent Versus Optimal Medical Therapy for Chronic Total Occlusion: Systematic Review and Meta-Analysis. | journal=Angiology | year= 2019 | volume= 70 | issue= 10 | pages= 908-915 | pmid=31256614 | doi=10.1177/0003319719858823 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=31256614  }} </ref><ref name="pmid31399762">{{cite journal| author=Li KHC, Wong KHG, Gong M, Liu T, Li G, Xia Y | display-authors=etal| title=Percutaneous Coronary Intervention Versus Medical Therapy for Chronic Total Occlusion of Coronary Arteries: A Systematic Review and Meta-Analysis. | journal=Curr Atheroscler Rep | year= 2019 | volume= 21 | issue= 10 | pages= 42 | pmid=31399762 | doi=10.1007/s11883-019-0804-8 | pmc=6689032 | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=31399762  }} </ref>


==References==
==References==

Latest revision as of 13:51, 1 July 2022

Percutaneous coronary intervention Microchapters

Home

Patient Information

Overview

Risk Stratification and Benefits of PCI

Preparation of the Patient for PCI

Equipment Used During PCI

Pharmacotherapy to Support PCI

Vascular Closure Devices

Recommendations for Perioperative Management–Timing of Elective Noncardiac Surgery in Patients Treated With PCI and DAPT

Post-PCI Management

Risk Reduction After PCI

Post-PCI follow up

Hybrid coronary revascularization

PCI approaches

PCI Complications

Factors Associated with Complications
Vessel Perforation
Dissection
Distal Embolization
No-reflow
Coronary Vasospasm
Abrupt Closure
Access Site Complications
Peri-procedure Bleeding
Restenosis
Renal Failure
Thrombocytopenia
Late Acquired Stent Malapposition
Loss of Side Branch
Multiple Complications

PCI in Specific Patients

Cardiogenic Shock
Left Main Coronary Artery Disease
Refractory Ventricular Arrhythmia
Severely Depressed Ventricular Function
Sole Remaining Conduit
Unprotected Left Main Patient
Adjuncts for High Risk PCI

PCI in Specific Lesion Types

Classification of the Lesion
The Calcified Lesion
The Ostial Lesion
The Angulated or Tortuous Lesion
The Bifurcation Lesion
The Long Lesion
The Bridge Lesion
Vasospasm
The Chronic Total Occlusion
The Left Internal Mammary Artery
Multivessel Disease
Distal Anastomotic Lesions
Left Main Intervention
The Thrombotic Lesion

Chronic total occlusions On the Web

Most recent articles

Most cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of Chronic total occlusions

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on Chronic total occlusions

CDC on Chronic total occlusions

Chronic total occlusions in the news

Blogs on Chronic total occlusions

Directions to Hospitals Treating Percutaneous coronary intervention

Risk calculators and risk factors for Chronic total occlusions

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editors-In-Chief: Duane Pinto, M.D.; Brian C. Bigelow, M.D.; Roger J. Laham, M.D.; Randall K. Harada, M.D.Sudarshana Datta, MD [2] Anahita Deylamsalehi, M.D.[3]

Click here to see a case of chronic total occlusion with retrograde approach on Tweetbook.

Overview

Chronic total occlusions (CTO) are often defined as coronary occlusions that have had TIMI 0 or 1 flow for an estimated duration of at least one month. Collateral flow to the distal territory maintains viability, but may be insufficient at times of increased oxygen demand, resulting in chronic stable angina or reduced exercise capacity. The tissue composition of the CTO is a variable mix of collagen-rich plaque, layered thrombus, calcium, and inflammatory cells with fibro-calcific caps at both ends. Neovascularization channels may form a neo-lumen or connect with adventitial vasa vasorum. The latter type of channels and bridging collaterals reduce the likelihood of successful guidewire advancement. Percutaneous interventions of CTO remain a technical challenge.

Epidemiology and Demographics

Rentrop Grade of Collateral Filling

Rentrop classification is helpful to define the collateral circulation of CTO. Rentrop et al. proposed the system below to grade collateral filling of recipient arteries:[3]

Rentrop Grade 0

No visible filling of any collateral channels.

Rentrop Grade 1

Collateral filling of branches of the vessel to be dilated without any dye reaching the epicardial segment of that vessel (ie, right coronary artery injection showing retrograde filling of septal branches to their origin from the left anterior descending artery, without visualization of the latter occluded artery).

Rentrop Grade 2

Partial collateral filling of the epicardial segment of the vessel being dilated.

Rentrop Grade 3

Complete collateral filling of the vessel being dilated.

Treatment

Goals of Treatment

Treatment Choices

There are three main treatment choices for CTO:

Medical Therapy

All patients should receive optimal medical therapies to reduce angina and cardiovascular events. Revascularization attempts may be considered for patients refractory to antianginal agents.

Percutaneous Revascularization

Surgical Revascularization

Patient selection

Contraindications to treatment include:

  • Techniques to assess viability prior to the procedure include:

Clinical predictors of success are very poor. Angiographic predictors of failure include:

  • Occlusion length > 15 mm (CT may be helpful in defining the length)
  • Moderate to severe coronary calcification
  • A flush, rounded or blunt (absence of a tapered "beak" at the origin ) occlusion
  • Presence of bridging collaterals
  • Higher age of the occlusion
  • Tortuosity
  • Small vessel size
  • Non-visualization of the distal vessel bed
  • The presence of a side branch at the occlusion site (the wire may selectively want to enter this rather than the total occlusion)

These predictors may also be assessed with CT, especially occlusion length. CT angiography may aid in choosing a retrograde approach via collaterals (CART and reverse CART technique) rather than the traditional antegrade approach.

PCI Techniques


Arterial Access and Guide Catheter Selection

Contralateral/ double coronary injection from a second catheter, and arterial access to fill the distal vessel bed via collaterals, may be useful for angiographic guidance of the distal wire.

Greater support is often required for CTO interventions, and good guiding catheter support may facilitate both wire and balloon passage. For the right coronary artery, a left or right Amplatz guiding catheter can provide excellent coaxial support. A guide with side holes is often helpful in dilating the right coronary artery. Extra backup (EBU or XB) guides are useful for the left coronary system. Consideration should be given to the use of 7-8 Fr guide sizes to accommodate extra equipment that may be needed. Further backup support could be provided by a larger caliber guide catheters (7 or 8 French).

Crossing The Lesion With The Wire

There are several potential choices for crossing a total occlusion. One standard progression in technique might include the following:

  1. Begin with a conventional softer tipped, less traumatic guidewire as a first step, before progressing to stiffer wires for occlusions with tougher caps. A conventional guidewire crosses > 90% of acute (< 3 month old) total occlusions.
  2. Several dedicated wires of graded stiffness were developed for CTO crossing, and a successful crossing frequently require trials of multiple different wires.
  • Non-hydrophilic or hydrophobic wires with an intermediate stiffness are a good first choice as they have a better tactile response, are less likely to lead to a subintimal position than a hydrophilic wire, and may have an additional advantage in their ability to cross the proximal cap of the occlusion. Choices in this class include the Miracle Bros 3 and the Asahi intermediate wires.
  • Hydrophilic wires may track better after the proximal cap of the occlusion has been crossed. Hydrophilic/coated wires have better maneuverability in tortuous or calcified vessels. Intermediate stiffness hydrophilic wire choices include the Choice PT XS (Extra Support), the Pilot 50, the Pilot 100 or the PT Graphix.
  • Shaping the wire tip using a modest angulation is better for blunted stump occlusions.
  • A low-profile balloon or exchange catheter adds backup support for wire penetration of fibro-calcific caps and may also be used cautiously for balloon-assisted progression within the occlusion.
  • Intra-luminal position of the wire distal to the occlusion is suggested by a freely rotating wire tip or angiography in different views by distal catheter or contralateral injections.
  • Stiffer wire tips will allow for a greater chance of crossing the proximal cap of the occlusion at the cost of an increased risk of the vessel dissection or perforation.
  • Stiff non-hydrophilic wires: The Miracle Bros 6, 9, and 12, Cross-IT, Confienza, Persuader
  • Stiff and hydrophilic (most aggressive): Pilot 200 and Shinobi

Crossing Lesions That Cannot Be Crossed With A Conventional Wire

Tapered-tip wires are occasionally better at navigating into a smaller channel than on 0.014” wire. Lasers, vibrational energy, blunt dissection (e.g. Lumend Frontrunner), and ultrasound catheters have been used with variable success to recanalize chronic total occlusions resistant to standard wires. Fixed wire-balloon systems do not offer the ability to switch out wires and perform distal injection.

Crossing The Lesion With A Balloon

Once the wire crossed the lesion, the next step is to perform angiography to confirm that you are intraluminal (i.e. that no dissection is present) and that wire perforation is not present. If dissection and wire perforation are not present, then an attempt is made to cross the lesion with a balloon. Fixed wire-balloon systems lack trackability and steer ability therefore over-the-wire systems are usually favored. Fixed wire systems may, however, occasionally be useful because of their very low profile which may allow passage in some cases in which a conventional over-the-wire system will not cross. Monorail systems are inferior to over-the-wire systems in this setting, because of their inferior balloon tracking characteristics, the inability to exchange guidewires and the inability to make a distal injection through the central lumen of the balloon to confirm your position. Often a low profile short over the wire balloon is a good first choice. An example would be a 1.5 mm X 6 mm balloon. Many investigators will remove the wire from the central lumen of the balloon and perform a distal injection at this point to confirm an intraluminal location of the balloon. If intraluminal guidewire position cannot be confirmed, balloon inflation should not be performed. If the balloon cannot be inserted all the way across lesion, inflation in proximal part of lesion can be performed to favorably alter anatomy and potentially facilitate eventual crossing. Consider aborting the procedure if, despite multiple attempts with various guidewires, the lesion cannot be crossed or successfully dilated; the risk of dissection or perforation may outweigh the benefit.

Special Techniques

  • If a wire enters a dissection plane, then a second wire may be used (parallel wire technique) to find a different pathway with the first wire serving as a reference or blocking repeat entry into the false lumen. Also, if a wire favors entering a side branch near the site of occlusion, then a balloon may be inflated in that side branch effecting a block to further wire entry.
  • After failed attempts of recanalizing the true lumen, a subintimal tracking and re-entry (STAR) technique may be considered. This is more safely performed in the RCA where major side branches are absent. Retrograde approaches through robust collaterals from the contralateral vessel have been employed with variable success rates.

Special Crossing Devices

Dilation of the Totally Occluded Lesion

Following initial conventional balloon angioplasty of the lesion, stent placement reduces restenosis, revascularization, and reocclusion rates. Placement of a drug eluting stent is a rational choice given the high risk of restenosis with this lesion type. Given that the lesion was totally occluded, the occurrence of stent thrombosis and complete reocclusion, while unfavorable, may not be as dangerous as it would be in an artery that was patent prior to placement of the stent. Other dilation techniques include rotational atherectomy and laser debulking.

More Tips
Advanced approaches to chronic total occlusions include
  • Anchor balloon technique Mother-child catheter (5 Fr within an 8 Fr guide)
  • Parallel wire and seesaw wiring
  • IVUS guidance to look for the true lumen
  • Retrograde approach (especially in previous antegrade failures)
  • Controlled antegrade and retrograde technique (CART)

Outcomes

  • The thrity day mortality rate after PCI of a CTO is 1.3%.[9]
  • Success rates of 50-80% have been reported but may be affected by selection or publication biases.
  • If the occlusion is less than 3 months old, the angiographic success rate is >90%, while patients with occlusions greater than 3 months old have a success rate of 70% and higher acute closure rates.
  • The most common reason for failure is the inability to cross the occlusion with a guidewire (80-90%). Other common reasons for failure are the inability for the balloon to cross the lesion (15%), and lesions cannot be dilated adequately (5%) (>30% residual stenosis). Calcifications are often a major obstacle to crossing the lesion.
  • Restenosis and reocclusion rates following successful PCI are higher in CTO compared to non-occlusive stenoses. These rates are improved with the use of DES.
  • Successful PCI of a CTO is associated with a 50-70% rate reduction of future CABG.
  • The salient complication of CTO PCI is perforation, which occurs in 4.8% of cases.[9]
  • If perforation occurs, it requires a rapid response: proximal balloon inflation, protamine administration for heparin reversal, consideration of a covered stent placement, and pericardiocentesis, if indicated.
  • Integration of several angiographic factors helps determine the likelihood of success (see above). No single factor should preclude a revascularization attempt.
Long-term outcomes
Trouble-shooting

Other Concerns

The decision to terminate the procedure if guidewires fail to cross the occlusion is based on the severity of symptoms (i.e. angina) weighed against the risk of more aggressive techniques/devices, fluoroscopy time, and contrast load).

2017 ACCF/AHA/SCAI Guidelines for Percutaneous Coronary Intervention

  • Up to 2011, only observational data had indicated the success of PCI over OMT (Optimal Medical therapy) in improving cardiovascular outcomes in patients with CTO.
  • However, three major randomized control trials were conducted between 2011-17. They were called EURO-CTO, DECISION-CTO and EXPLORE.[10]
  • These trials concluded that PCI was non-superior to OMT in patients with at least 1 CTO.[11]
  • In 2017, the updated ACC/AATS/AHA/ASE/ASNC/SCAI/SCCT/STS 2017 Appropriate Use Criteria (AUC) for Coronary Revascularization in Patients With Stable Ischemic Heart Disease (SIHD) was characterized by:[12]

2011 ACCF/AHA/SCAI Guidelines for Percutaneous Coronary Intervention (DO NOT EDIT)[13]

Chronic Total Occlusions[13]

  • In 2011, The AHA assigned a Class IIa recommendation for CTO-PCI.
Class IIa
"1. PCI of a chronic total occlusion in patients with appropriate clinical indications and suitable anatomy is reasonable when performed by operators with appropriate expertise.[4][14][15][16][17] (Level of Evidence: B)"

2021 ACA Revascularization Guideline

Class 2b Recommendation, Level of Evidence: B-R[6]
After treatment of non-CTO lesions in patients with refractory angina on medical therapy, the benefit of PCI of a CTO to diminish symptoms is uncertain
  • Despite appreciable retrospective and registry data proposing some benefits, there is no clear benefit demonstration from prospective randomized trials.[18][19]

References

  1. Fefer P, Knudtson ML, Cheema AN, Galbraith PD, Osherov AB, Yalonetsky S; et al. (2012). "Current perspectives on coronary chronic total occlusions: the Canadian Multicenter Chronic Total Occlusions Registry". J Am Coll Cardiol. 59 (11): 991–7. doi:10.1016/j.jacc.2011.12.007. PMID 22402070.
  2. Tsai TT, Stanislawski MA, Shunk KA, Armstrong EJ, Grunwald GK, Schob AH; et al. (2017). "Contemporary Incidence, Management, and Long-Term Outcomes of Percutaneous Coronary Interventions for Chronic Coronary Artery Total Occlusions: Insights From the VA CART Program". JACC Cardiovasc Interv. 10 (9): 866–875. doi:10.1016/j.jcin.2017.02.044. PMID 28473108.
  3. Rentrop, K. P. (1985-03). "Changes in collateral channel filling immediately after controlled coronary artery occlusion by an angioplasty balloon in human subjects". Journal of the American College of Cardiology. 5 (3): 587–592. ISSN 0735-1097. PMID 3156171. Unknown parameter |coauthors= ignored (help); Check date values in: |date= (help)
  4. 4.0 4.1 Olivari Z, Rubartelli P, Piscione F; et al. (2003). "Immediate results and one-year clinical outcome after percutaneous coronary interventions in chronic total occlusions: data from a multicenter, prospective, observational study (TOAST-GISE)". J. Am. Coll. Cardiol. 41 (10): 1672–8. PMID 12767645. Unknown parameter |month= ignored (help)
  5. Rahel BM, Laarman GJ, Kelder JC, Ten Berg JM, Suttorp MJ (2009). "Three-year clinical outcome after primary stenting of totally occluded native coronary arteries: a randomized comparison of bare-metal stent implantation with sirolimus-eluting stent implantation for the treatment of total coronary occlusions (Primary Stenting of Totally Occluded Native Coronary Arteries [PRISON] II study)". Am. Heart J. 157 (1): 149–55. doi:10.1016/j.ahj.2008.08.025. PMID 19081412. Unknown parameter |month= ignored (help)
  6. 6.0 6.1 Writing Committee Members. Lawton JS, Tamis-Holland JE, Bangalore S, Bates ER, Beckie TM; et al. (2022). "2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines". J Am Coll Cardiol. 79 (2): e21–e129. doi:10.1016/j.jacc.2021.09.006. PMID 34895950 Check |pmid= value (help).
  7. Werner GS, Martin-Yuste V, Hildick-Smith D, Boudou N, Sianos G, Gelev V; et al. (2018). "A randomized multicentre trial to compare revascularization with optimal medical therapy for the treatment of chronic total coronary occlusions". Eur Heart J. 39 (26): 2484–2493. doi:10.1093/eurheartj/ehy220. PMID 29722796.
  8. Lee SW, Lee PH, Ahn JM, Park DW, Yun SC, Han S; et al. (2019). "Randomized Trial Evaluating Percutaneous Coronary Intervention for the Treatment of Chronic Total Occlusion". Circulation. 139 (14): 1674–1683. doi:10.1161/CIRCULATIONAHA.118.031313. PMID 30813758.
  9. 9.0 9.1 Sapontis J, Salisbury AC, Yeh RW, Cohen DJ, Hirai T, Lombardi W; et al. (2017). "Early Procedural and Health Status Outcomes After Chronic Total Occlusion Angioplasty: A Report From the OPEN-CTO Registry (Outcomes, Patient Health Status, and Efficiency in Chronic Total Occlusion Hybrid Procedures)". JACC Cardiovasc Interv. 10 (15): 1523–1534. doi:10.1016/j.jcin.2017.05.065. PMID 28797429.
  10. "Appropriateness of CTO PCI in Patients With SIHD - American College of Cardiology".
  11. "Optimal Medical Therapy With or Without Stenting For Coronary Chronic Total Occlusion - American College of Cardiology".
  12. "Appropriate Use Criteria for Coronary Revascularization in Stable Ischemic Heart Disease - American College of Cardiology".
  13. 13.0 13.1 Levine GN, Bates ER, Blankenship JC, Bailey SR, Bittl JA, Cercek B, Chambers CE, Ellis SG, Guyton RA, Hollenberg SM, Khot UN, Lange RA, Mauri L, Mehran R, Moussa ID, Mukherjee D, Nallamothu BK, Ting HH (2011). "2011 ACCF/AHA/SCAI Guideline for Percutaneous Coronary Intervention: Executive Summary A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines and the Society for Cardiovascular Angiography and Interventions" (PDF). Journal of the American College of Cardiology. 58 (24): 2550–83. doi:10.1016/j.jacc.2011.08.006. PMID 22070837. Retrieved 2011-12-08. Text "PDF" ignored (help); Unknown parameter |month= ignored (help)
  14. Suero JA, Marso SP, Jones PG, Laster SB, Huber KC, Giorgi LV, Johnson WL, Rutherford BD (2001). "Procedural outcomes and long-term survival among patients undergoing percutaneous coronary intervention of a chronic total occlusion in native coronary arteries: a 20-year experience". Journal of the American College of Cardiology. 38 (2): 409–14. PMID 11499731. Retrieved 2011-12-15. Unknown parameter |month= ignored (help)
  15. de Labriolle A, Bonello L, Roy P, Lemesle G, Steinberg DH, Xue Z, Kaneshige K, Suddath WO, Satler LF, Kent KM, Pichard AD, Lindsay J, Waksman R (2008). "Comparison of safety, efficacy, and outcome of successful versus unsuccessful percutaneous coronary intervention in "true" chronic total occlusions". The American Journal of Cardiology. 102 (9): 1175–81. doi:10.1016/j.amjcard.2008.06.059. PMID 18940287. Retrieved 2011-12-15. Unknown parameter |month= ignored (help)
  16. Rathore S, Matsuo H, Terashima M, Kinoshita Y, Kimura M, Tsuchikane E, Nasu K, Ehara M, Asakura Y, Katoh O, Suzuki T (2009). "Procedural and in-hospital outcomes after percutaneous coronary intervention for chronic total occlusions of coronary arteries 2002 to 2008: impact of novel guidewire techniques". JACC. Cardiovascular Interventions. 2 (6): 489–97. doi:10.1016/j.jcin.2009.04.008. PMID 19539251. Retrieved 2011-12-15. Unknown parameter |month= ignored (help)
  17. Stone GW, Reifart NJ, Moussa I, Hoye A, Cox DA, Colombo A, Baim DS, Teirstein PS, Strauss BH, Selmon M, Mintz GS, Katoh O, Mitsudo K, Suzuki T, Tamai H, Grube E, Cannon LA, Kandzari DE, Reisman M, Schwartz RS, Bailey S, Dangas G, Mehran R, Abizaid A, Moses JW, Leon MB, Serruys PW (2005). "Percutaneous recanalization of chronically occluded coronary arteries: a consensus document: part II". Circulation. 112 (16): 2530–7. doi:10.1161/CIRCULATIONAHA.105.583716. PMID 16230504. Retrieved 2011-12-15. Unknown parameter |month= ignored (help)
  18. Abo-Aly M, Misumida N, Backer N, ElKholey K, Kim SM, Ogunbayo GO; et al. (2019). "Percutaneous Coronary Intervention With Drug-Eluting Stent Versus Optimal Medical Therapy for Chronic Total Occlusion: Systematic Review and Meta-Analysis". Angiology. 70 (10): 908–915. doi:10.1177/0003319719858823. PMID 31256614.
  19. Li KHC, Wong KHG, Gong M, Liu T, Li G, Xia Y; et al. (2019). "Percutaneous Coronary Intervention Versus Medical Therapy for Chronic Total Occlusion of Coronary Arteries: A Systematic Review and Meta-Analysis". Curr Atheroscler Rep. 21 (10): 42. doi:10.1007/s11883-019-0804-8. PMC 6689032 Check |pmc= value (help). PMID 31399762.

Template:WikiDoc Sources