Chronic stable angina myocardial perfusion scintigraphy: Difference between revisions

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__NOTOC__
{{Chronic stable angina}}
{{Chronic stable angina}}
'''Editors-In-Chief:''' [[C. Michael Gibson, M.S., M.D.]] [mailto:mgibson@perfuse.org] Phone:617-632-7753; {{CZ}}; '''Associate Editor-in-Chief:''' Smita Kohli, M.D.


'''''Synonyms and keywords:''''' myocardial perfusion imaging, MPI, myocardial perfusion scan, stress thalium scan.
'''Editor-In-Chief:''' [[C. Michael Gibson, M.S., M.D.]] [mailto:charlesmichaelgibson@gmail.com]; '''Associate Editor(s)-In-Chief:''' {{CZ}}; Smita Kohli, M.D.; [[Lakshmi Gopalakrishnan|Lakshmi Gopalakrishnan, M.B.B.S.]]; {{AA}}


==Myocardial Perfusion Scintigraphy==
{{SK}} Myocardial perfusion imaging, MPI, myocardial perfusion scan, exercise myocardial perfusion imaging, stress thalium scan, nuclear stress test.
[[Image:MPI_SPECT.jpg|frame|left|SPECT images of myocardial perfusion showing a reversible perfusion defect in inferior and lateral walls(Note the defect present in stress but not in rest images)]]


*Myocardial perfusion scintigraphy with '''thallium-201''' is frequently employed as a noninvasive test to evaluate abnormalities of myocardial perfusion in patients with established or suspected [[CAD]].  
==Overview==
In patients with baseline [[Chronic stable angina electrocardiography|ECG abnormalities]], a myocardial perfusion test can be used to localize the region of [[ischemia]]. Thallium-201 and technetium-99m are the two radio-labeled agents that are frequently used for the assessment of  myocardial perfusion. Myocardial uptake of thallium-201 chloride is directly proportional to the regional myocardial blood flow and is dependent on the presence of viable myocardium. In patients with known [[CAD]], a normal thallium stress test without a perfusion defect is indicative of a benign process and associated with excellent prognosis. Patients with a normal thallium scan are at low risk for [[CAD]] and subsequent coronary angiography is indicated only if the patient has a [[Chronic stable angina prognosis#Duke Score (Exercise Treadmill Test)|high probabilty Duke treadmill score]]. Contraindications for thallium stress test include the presence of [[arrhythmia]], acute [[myocarditis]], [[aortic stenosis|severe aortic stenosis]] and acute [[MI]] within the past 2 days.


==Stress Thallium-201 Test==
===Indications===
*Myocardial perfusion scintigraphy with thallium-201 is frequently employed as a noninvasive test to evaluate abnormalities of myocardial perfusion in patients with established or suspected [[CAD]].
*Thallium images may be planar or tomographic (single photon emission computed tomography i.e. SPECT). The latter are more accurate and are therefore used more frequently to assess the presence and extent of ischemic and infarcted myocardium.
===Mechanism of Benefit===
*Myocardial uptake of thallium-201 chloride is proportional to regional myocardial blood flow and is dependent on the presence of viable myocardium.  
*Myocardial uptake of thallium-201 chloride is proportional to regional myocardial blood flow and is dependent on the presence of viable myocardium.  


*During exercise, the magnitude of the increase in blood flow to the non-ischemic myocardial zones is greater than to the zones supplied by stenotic coronary arteries. Owing to this heterogeneous distribution of blood flow, the relative extraction of thallium by non-ischemic myocardium is greater than that by ischemic myocardium.
*During exercise, the magnitude of the increase in blood flow to the non-ischemic myocardial zones is greater than to the zones supplied by stenotic coronary arteries. Due to heterogeneous distribution of blood flow, the relative extraction of thallium by non-ischemic myocardium is greater than that by ischemic myocardium.
:*During exercise thallium testing, the isotope is administered intravenously during peak exercise, and '''stress''' images are obtained immediately after discontinuation of exercise. These images reveal a decreased uptake by the ischemic myocardium, creating a '''perfusion defect'''.  
:*During exercise thallium testing, the isotope is administered intravenously during peak exercise, and stress images are obtained immediately after discontinuation of exercise. These images reveal a decreased uptake by the ischemic myocardium, creating a perfusion defect.  
:*Redistribution images are obtained after 4 hours. Myocardium that was ischemic during stress but that is not ischemic at rest now extracts the isotope. Therefore, the perfusion defects during stress images are not observed in the rest images, and these '''reversible perfusion defects''' indicate the presence of '''viable myocardium'''.  
:*Redistribution images are obtained after 4 hours. Myocardium that was ischemic during stress but that is not ischemic at rest now extracts the isotope. Therefore, the perfusion defects during stress images are not observed in the rest images, and these reversible perfusion defects indicate the presence of viable myocardium.  
:*If the perfusion defects in stress images persist in the rest images, that is, if the '''perfusion defects are fixed''', the myocardium is usually '''necrotic or fibrotic'''.  
:*If the perfusion defects in stress images persist in the rest images, that is, if the perfusion defects are fixed, the myocardium is usually necrotic or fibrotic.  


*A repeat injection of thallium and scanning 24 hours after stress can distinguish severely ischemic area from viable myocardium.
:*A repeat injection of thallium and scanning 24 hours after stress can distinguish severely ischemic area from viable myocardium.
*Thallium images may be planar or tomographic (single photon emission computed tomography='''SPECT'''). The latter are more accurate and are therefore used more frequently to assess the presence and extent of ischemic and infarcted myocardium.  


'''Sensitivity and Specificity of Myocardial Perfusion Scintigraphy:'''
===Sensitivity and Specificity===
*In pooled analyses from multiple studies, the sensitivity for detecting [[coronary artery disease|coronary artery disease (CAD)]] using exercise [[treadmill]] thallium myocardium scintigraphy was approximately 84%. The specificity of excluding [[CAD]] using this test was approximately 88%. The sensitivity approaches 90% with a quantitative computer-assisted analysis of the images; during which, there is no loss of specificity.
:*Considerable experience is required for the performance and interpretation of exercise thallium scintigraphy to achieve a high degree of specificity and sensitivity.
*Exercise thallium scintigraphy is less likely than [[Chronic stable angina exercise electrocardiography|exercise ECG]] to provide false positive test results in women.
*Exercise thalloum scintigraphy may, however, give false positive test results in patients with:
:*[[Hypertrophic cardiomyopathy]]
:*[[Dilated cardiomyopathy]]
:*[[Restrictive cardiomyopathy|Infiltrative cardiomyopathy]]
*Like the [[Chronic stable angina exercise electrocardiography|exercise ECG]], thallium stress scintigraphy is less sensitive in the diagnosis of single vessel disease, particularly of circumflex coronary artery stenosis, than in multi-vessel coronary artery disease.


*In pooled analyses from multiple studies, exercise [[treadmill]] thallium myocardium scintigraphy has sensitivity for detecting [[CAD]] and specificity for excluding it of about 84% and 88%, respectively. The sensitivity approaches 90% with a quantitative computer-assisted analysis of the images without loss of specificity.
==Technetium-99m==
*Technetium-99m, a calcium analog with a higher photon energy and a shorter half life than thallium chloride, can be linked to a variety of agents.  
*Considerable experience is required for the performance and interpretation of exercise thallium scintigraphy to achieve these high degrees of specificity and sensitivity.  
*Technetium-99m-sestamibi is an isonitrile compound that, like thallium, is taken up by the myocardium proportional to blood flow but in contrast to thallium does not undergo redistribution.
===Indications===
*Technetium-99m is used as a marker of myocardial perfusion.
*Tomographic images with technetium-99m also allow images to be acquired on the first pass through the ventricle and can be used to assess the [[ejection fraction|left ventricular ejection fraction]].
*As a noninvasive, less expensive and readily available test at care centers, [[Chronic stable angina echocardiography|echocardiography]] is usually the preferable method for this purpose.


*Exercise thallium scintigraphy is less likely than exercise electrocardiography to provide false positive test results in women, but it may give false positive test results in patients with hypertrophic, dilated and infiltrative cardiomyopathies.  
''For more information on stress radionuclide myocardial perfusion imaging, click [[Exercise stress testing#Stress Radionuclide Myocardial Perfusion Imaging|here]].''


*Like the exercise ECG, thallium stress scintigraphy is less sensitive in the diagnosis of single vessel disease, particularly of circumflex coronary artery stenosis, than in multi vessel coronary artery disease.
''For more information on comparison of exercise SPECT imaging and exercise echocardiography, click [[Exercise stress testing#Comparison of exercise SPECT imaging and Exercise Echocardiography|here]].''
'''Technetium-99m:'''
*Technetium-99m, a calcium analog with a higher photon energy and a shorter half life than thallium chloride, can be linked to a variety of agents and used as a marker of myocardial perfusion.
*Technetium-99m-sestamibi is an isonitrile compound that, like thallium, is taken up by the myocardium proportional to blood flow but in contrast to thallium does not undergo redistribution. 
*Tomographic images with technetium-99m also allow images to be acquired on the first pass through the ventricle and can be used to assess the left ventricular ejection fraction. However, as a noninvasive, less expensive and readily available test at more centers, echocardiography is usually preferable method for this purpose.


==ACC / AHA Guidelines- Nuclear Stress Testing in patients Who Are Able to Exercise (DO NOT EDIT)<ref name="Gibbons1"> Gibbons RJ, Chatterjee K, Daley J, et al. ACC/AHA/ACP–ASIM guidelines for the management of patients with chronic stable angina: executive summary and recommendations: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee on Management of Patients With Chronic Stable Angina). Circulation. 1999; 99: 2829–2848. PMID 10351980</ref>==
''For more information on techniques used to assess myocardial viability, click [[Exercise stress testing#Techniques used to Assess Myocardial Viability|here]].''
{{cquote|
===Class I===
'''1.''' Exercise myocardial perfusion imaging or exercise [[echocardiography]] in patients with an intermediate pretest probability of [[CAD]] who have 1 of the following baseline [[ECG]] abnormalities:
:a. Preexcitation ([[Wolff-Parkinson-White syndrome|Wolff-Parkinson-White]]) syndrome. ''(Level of Evidence: B)''
:b. More than 1 mm of rest ST depression. ''(Level of Evidence: B)''


'''2.''' Exercise myocardial perfusion imaging or exercise [[echocardiography]] in patients with prior [[revascularization]] (either [[percutaneous transluminal coronary angioplasty]] ([[PTCA]]) or [[coronary artery bypass graft]] ([[CABG]]). ''(Level of Evidence: B)''
==ACC/AHA Guidelines- Nuclear Stress Testing in patients Who Are Able to Exercise (DO NOT EDIT)<ref name="pmid23166210">{{cite journal| author=Fihn SD, Gardin JM, Abrams J, Berra K, Blankenship JC, Dallas AP et al.| title=2012 ACCF/AHA/ACP/AATS/PCNA/SCAI/STS guideline for the diagnosis and management of patients with stable ischemic heart disease: executive summary: a report of the American College of Cardiology Foundation/American Heart Association task force on practice guidelines, and the American College of Physicians, American Association for Thoracic Surgery, Preventive Cardiovascular Nurses Association, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons. | journal=Circulation | year= 2012 | volume= 126 | issue= 25 | pages= 3097-137 | pmid=23166210 | doi=10.1161/CIR.0b013e3182776f83 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=23166210  }} </ref>==
'''Patients able to exercise'''


'''3.''' [[Adenosine]] or [[dipyridamole]] myocardial perfusion imaging in patients with an intermediate pretest probability of [[CAD]] and 1 of the following baseline [[ECG]] abnormalities:
{|class="wikitable"
:a. Electronically paced ventricular rhythm. ''(Level of Evidence: C)''
|-
:b. [[Left bundle-branch block]]. ''(Level of Evidence: B)''
| colspan="1" style="text-align:center; background:LightGreen"|[[ACC AHA guidelines classification scheme#Classification of Recommendations|Class I]]


===Class IIb===
|-
'''1.''' Exercise myocardial perfusion imaging and exercise [[echocardiography]] in patients with a low or high probability of [[CAD]] who have 1 of the following baseline [[ECG]] abnormalities:
| bgcolor="LightGreen"|<nowiki>"</nowiki>'''1.''' Exercise stress with nuclear MPI or echocardiography is recommended for patients with an intermediate to high pretest probability of IHD who have an uninterpretable ECG and at least moderate physical functioning or no disabling comorbidity ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: B]])''
:a. Preexcitation ([[Wolff-Parkinson-White|Wolff-Parkinson-White]]) syndrome. ''(Level of Evidence: B)''
:b. More than 1 mm of ST depression. ''(Level of Evidence: B)''


'''2.''' [[Adenosine]] or [[dipyridamole]] myocardial perfusion imaging in patients with a low or high probability of [[CAD]] and 1 of the following baseline [[ECG]] abnormalities:
|}
:a. Electronically paced ventricular rhythm. ''(Level of Evidence: C)''
:b. [[Left bundle-branch block]]. ''(Level of Evidence: B)''
{|class="wikitable"
|-
| colspan="1" style="text-align:center; background:LemonChiffon"|[[ACC AHA guidelines classification scheme#Classification of Recommendations|Class IIa]]


'''3.''' Exercise myocardial perfusion imaging or exercise [[echocardiography]] in patients with an intermediate probability of [[CAD]] who have 1 of the following:
|-
:a. [[Digoxin]] use with <1 mm ST depression on their baseline [[ECG]]. ''(Level of Evidence: B)''
| bgcolor="LemonChiffon"|<nowiki>"</nowiki>'''1.''' Exercise stress with nuclear MPI or echocardiography is reasonable for patients with an intermediatge to high pretest probability of obstructive IHD who have an interpretable ECG and at least moderate physical functioning or no disabling comorbidity ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: B]])''
:b. [[LV hypertrophy]] with <1 mm ST depression on their baseline [[ECG]]. ''(Level of Evidence: B)''


'''4.''' Exercise myocardial perfusion imaging, exercise [[echocardiography]], [[adenosine]] or [[dipyridamole]] myocardial perfusion imaging, or [[dobutamine]] [[echocardiography]] as the initial stress test in a patient with a normal rest [[ECG]] who is not taking [[digoxin]]. ''(Level of Evidence: B)''
|}


'''5.''' Exercise or [[dobutamine]] [[echocardiography]] in patients with [[left bundle-branch block]]. ''(Level of Evidence: C)''}}
{|class="wikitable"
|-
| colspan="1" style="text-align:center; background:Lightcoral"|[[ACC AHA guidelines classification scheme#Classification of Recommendations|Class III]]


==See Also==
|-
*[[The Living Guidelines: Chronic Stable Angina Pectoris | The Chronic Stable Angina Living Guidelines: Vote on current recommendations and suggest revisions to the guidelines]]
| bgcolor="Lightcoral"|<nowiki>"</nowiki>'''1.''' Exercise stress with nuclear MPI or echocardiography is reasonable for patients with an intermediate to high pretest probability of obstructive IHD who have an interpretable ECG and at least moderate physical functioning or no disabling comorbidity ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: B]])''


==Sources==
|-
*TheACC/AHA 2002 Guideline Update for the Management of Patients With Chronic Stable Angina <ref name="Gibbons2">Gibbons RJ, Abrams J, Chatterjee K, Daley J, Deedwania PC, Douglas JS, Ferguson TB Jr, Fihn SD, Fraker TD Jr, Gardin JM, O'Rourke RA, Pasternak RC, Williams SV, Gibbons RJ, Alpert JS, Antman EM, Hiratzka LF, Fuster V, Faxon DP, Gregoratos G, Jacobs AK, Smith SC Jr; American College of Cardiology; American Heart Association Task Force on Practice Guidelines. Committee on the Management of Patients With Chronic Stable Angina. ACC/AHA 2002 guideline update for the management of patients with chronic stable angina--summary article: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee on the Management of Patients With Chronic Stable Angina). Circulation. 2003 Jan 7; 107 (1): 149-58. PMID 12515758 </ref>
|bgcolor="Lightcoral"|<nowiki>"</nowiki>'''2.''' Exercise stress with nuclear MPI is not recommended as an initial test in low-risk patients who have an interpretable ECG and at least moderate physical functioning or no disabling comorbidity.''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: C]])''
|}
'''Patients unable to exercise'''
{|class="wikitable"
|-
| colspan="1" style="text-align:center; background:LightGreen"|[[ACC AHA guidelines classification scheme#Classification of Recommendations|Class I]]


*The ACC/AHA/ACP–ASIM Guidelines for the Management of Patients With Chronic Stable Angina <ref name="Gibbons1"> Gibbons RJ, Chatterjee K, Daley J, et al. ACC/AHA/ACP–ASIM guidelines for the management of patients with chronic stable angina: executive summary and recommendations: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee on Management of Patients With Chronic Stable Angina). Circulation. 1999; 99: 2829–2848. PMID 10351980</ref>
|-
| bgcolor="LightGreen"|<nowiki>"</nowiki>'''1.'''Pharmacological stress with nuclear MPI or echocardiography is recommended for patients with an intermediate to high pretest probability of IHD who are incapable of at least moderate physical functioning or have disabling comorbidity ''([[ACC AHA guidelines classification scheme#Level of Evidence|Level of Evidence: B]])''


*The 2007 Chronic Angina Focused Update of the ACC/AHA 2002 Guidelines for the Management of Patients With Chronic Stable Angina <ref name="Fraker"> Fraker TD Jr, Fihn SD, Gibbons RJ, Abrams J, Chatterjee K, Daley J, Deedwania PC, Douglas JS, Ferguson TB Jr, Gardin JM, O'Rourke RA, Williams SV, Smith SC Jr, Jacobs AK, Adams CD, Anderson JL, Buller CE, Creager MA, Ettinger SM, Halperin JL, Hunt SA, Krumholz HM, Kushner FG, Lytle BW, Nishimura R, Page RL, Riegel B, Tarkington LG, Yancy CW; American College of Cardiology; American Heart Association; American College of Cardiology/American Heart Association Task Force on Practice Guidelines Writing Group. 2007 chronic angina focused update of the ACC/AHA 2002 Guidelines for the management of patients with chronic stable angina: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines Writing Group to develop the focused update of the 2002 Guidelines for the management of patients with chronic stable angina. Circulation. 2007 Dec 4; 116 (23): 2762-72. Epub 2007 Nov 12. PMID 17998462 </ref>
|}


==References==
==References==
{{Reflist|2}}
{{reflist|2}}


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Latest revision as of 22:31, 29 October 2016

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-In-Chief: Cafer Zorkun, M.D., Ph.D. [2]; Smita Kohli, M.D.; Lakshmi Gopalakrishnan, M.B.B.S.; Aysha Anwar, M.B.B.S[3]

Synonyms and keywords: Myocardial perfusion imaging, MPI, myocardial perfusion scan, exercise myocardial perfusion imaging, stress thalium scan, nuclear stress test.

Overview

In patients with baseline ECG abnormalities, a myocardial perfusion test can be used to localize the region of ischemia. Thallium-201 and technetium-99m are the two radio-labeled agents that are frequently used for the assessment of myocardial perfusion. Myocardial uptake of thallium-201 chloride is directly proportional to the regional myocardial blood flow and is dependent on the presence of viable myocardium. In patients with known CAD, a normal thallium stress test without a perfusion defect is indicative of a benign process and associated with excellent prognosis. Patients with a normal thallium scan are at low risk for CAD and subsequent coronary angiography is indicated only if the patient has a high probabilty Duke treadmill score. Contraindications for thallium stress test include the presence of arrhythmia, acute myocarditis, severe aortic stenosis and acute MI within the past 2 days.

Stress Thallium-201 Test

Indications

  • Myocardial perfusion scintigraphy with thallium-201 is frequently employed as a noninvasive test to evaluate abnormalities of myocardial perfusion in patients with established or suspected CAD.
  • Thallium images may be planar or tomographic (single photon emission computed tomography i.e. SPECT). The latter are more accurate and are therefore used more frequently to assess the presence and extent of ischemic and infarcted myocardium.

Mechanism of Benefit

  • Myocardial uptake of thallium-201 chloride is proportional to regional myocardial blood flow and is dependent on the presence of viable myocardium.
  • During exercise, the magnitude of the increase in blood flow to the non-ischemic myocardial zones is greater than to the zones supplied by stenotic coronary arteries. Due to heterogeneous distribution of blood flow, the relative extraction of thallium by non-ischemic myocardium is greater than that by ischemic myocardium.
  • During exercise thallium testing, the isotope is administered intravenously during peak exercise, and stress images are obtained immediately after discontinuation of exercise. These images reveal a decreased uptake by the ischemic myocardium, creating a perfusion defect.
  • Redistribution images are obtained after 4 hours. Myocardium that was ischemic during stress but that is not ischemic at rest now extracts the isotope. Therefore, the perfusion defects during stress images are not observed in the rest images, and these reversible perfusion defects indicate the presence of viable myocardium.
  • If the perfusion defects in stress images persist in the rest images, that is, if the perfusion defects are fixed, the myocardium is usually necrotic or fibrotic.
  • A repeat injection of thallium and scanning 24 hours after stress can distinguish severely ischemic area from viable myocardium.

Sensitivity and Specificity

  • In pooled analyses from multiple studies, the sensitivity for detecting coronary artery disease (CAD) using exercise treadmill thallium myocardium scintigraphy was approximately 84%. The specificity of excluding CAD using this test was approximately 88%. The sensitivity approaches 90% with a quantitative computer-assisted analysis of the images; during which, there is no loss of specificity.
  • Considerable experience is required for the performance and interpretation of exercise thallium scintigraphy to achieve a high degree of specificity and sensitivity.
  • Exercise thallium scintigraphy is less likely than exercise ECG to provide false positive test results in women.
  • Exercise thalloum scintigraphy may, however, give false positive test results in patients with:
  • Like the exercise ECG, thallium stress scintigraphy is less sensitive in the diagnosis of single vessel disease, particularly of circumflex coronary artery stenosis, than in multi-vessel coronary artery disease.

Technetium-99m

  • Technetium-99m, a calcium analog with a higher photon energy and a shorter half life than thallium chloride, can be linked to a variety of agents.
  • Technetium-99m-sestamibi is an isonitrile compound that, like thallium, is taken up by the myocardium proportional to blood flow but in contrast to thallium does not undergo redistribution.

Indications

  • Technetium-99m is used as a marker of myocardial perfusion.
  • Tomographic images with technetium-99m also allow images to be acquired on the first pass through the ventricle and can be used to assess the left ventricular ejection fraction.
  • As a noninvasive, less expensive and readily available test at care centers, echocardiography is usually the preferable method for this purpose.

For more information on stress radionuclide myocardial perfusion imaging, click here.

For more information on comparison of exercise SPECT imaging and exercise echocardiography, click here.

For more information on techniques used to assess myocardial viability, click here.

ACC/AHA Guidelines- Nuclear Stress Testing in patients Who Are Able to Exercise (DO NOT EDIT)[1]

Patients able to exercise

Class I
"1. Exercise stress with nuclear MPI or echocardiography is recommended for patients with an intermediate to high pretest probability of IHD who have an uninterpretable ECG and at least moderate physical functioning or no disabling comorbidity (Level of Evidence: B)
Class IIa
"1. Exercise stress with nuclear MPI or echocardiography is reasonable for patients with an intermediatge to high pretest probability of obstructive IHD who have an interpretable ECG and at least moderate physical functioning or no disabling comorbidity (Level of Evidence: B)
Class III
"1. Exercise stress with nuclear MPI or echocardiography is reasonable for patients with an intermediate to high pretest probability of obstructive IHD who have an interpretable ECG and at least moderate physical functioning or no disabling comorbidity (Level of Evidence: B)
"2. Exercise stress with nuclear MPI is not recommended as an initial test in low-risk patients who have an interpretable ECG and at least moderate physical functioning or no disabling comorbidity.(Level of Evidence: C)

Patients unable to exercise

Class I
"1.Pharmacological stress with nuclear MPI or echocardiography is recommended for patients with an intermediate to high pretest probability of IHD who are incapable of at least moderate physical functioning or have disabling comorbidity (Level of Evidence: B)

References

  1. ↑ Fihn SD, Gardin JM, Abrams J, Berra K, Blankenship JC, Dallas AP; et al. (2012). "2012 ACCF/AHA/ACP/AATS/PCNA/SCAI/STS guideline for the diagnosis and management of patients with stable ischemic heart disease: executive summary: a report of the American College of Cardiology Foundation/American Heart Association task force on practice guidelines, and the American College of Physicians, American Association for Thoracic Surgery, Preventive Cardiovascular Nurses Association, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons". Circulation. 126 (25): 3097–137. doi:10.1161/CIR.0b013e3182776f83. PMID 23166210.


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