Renal artery stenosis overview: Difference between revisions

Jump to navigation Jump to search
No edit summary
 
(17 intermediate revisions by the same user not shown)
Line 4: Line 4:


==Overview==
==Overview==
Renal artery stenosis is defined as the unilateral or bilateral progressive narrowing of the renal arteries or their proximal branches of more than 50% in diameter. It is a heterogeneous group of diseases that most commonly include: fibromuscular dysplasia (FMD) and atherosclerotic renal artery stenosis (ARAS). Although renal artery stenosis may be an isolated asymptomatic condition, it may commonly lead to secondary hypertension that is thus called renovascular hypertension (RVHT), ischemic nephropathy, and chronic renal insufficiency.


Approximately 90% of renal artery stenosis cases occur due to progressive atherosclerosis. The ostium and proximal third of the renal arteries are the most commonly involved regions in atherosclerosis. Nonetheless, segmental and diffuse atherosclerosis may still be seen in the minority of patients, especially in context of chronic kidney disease and poor renal survival.
*[[Renal artery stenosis|Renal artery stenosis (RAS)]] is defined as the unilateral or bilateral progressive narrowing of the [[renal arteries]] or their proximal branches of more than 50% in diameter.
*[[Renal artery stenosis|RAS]] is a heterogeneous group of diseases that most commonly include: [[Fibromuscular dysplasia|fibromuscular dysplasia (FMD)]] and [[atherosclerotic]] renal artery stenosis (ARAS).
*Although [[renal artery stenosis]] may be an isolated asymptomatic condition,
*It may commonly lead to [[secondary hypertension]] that is thus called [[renovascular hypertension (RVHT)]], [[ischemic nephropathy]], and [[Chronic renal insufficiency|chronic renal insufficiency.]]
 
*Approximately 90% of [[renal artery stenosis]] cases occur due to progressive [[atherosclerosis]].
*The ostium and proximal third of the renal arteries are the most commonly involved regions in [[atherosclerosis]].
*Segmental and diffuse atherosclerosis may still be seen in the minority of patients, especially in context of [[chronic kidney disease]] and poor renal survival.


==Pathophysiology==
==Pathophysiology==
The main pathophysiological mechanism behind renal artery stenosis is reduction in renal blood flow secondary to renal artery stenosis which stimulates renin release from the juxtaglomerular apparatus through activation of the tubuloglomerular feedback, baroreceptor reflex, and the sympathetic nervous system. Elevated angiotensin II activities in turn cause elevation of the arterial pressure and other effects including aldosterone secretion, sodium retention, and left ventricular hypertrophy and remodeling.<ref name="Garovic-2005">{{Cite journal  | last1 = Garovic | first1 = VD. | last2 = Textor | first2 = SC. | title = Renovascular hypertension and ischemic nephropathy. | journal = Circulation | volume = 112 | issue = 9 | pages = 1362-74 | month = Aug | year = 2005 | doi = 10.1161/CIRCULATIONAHA.104.492348 | PMID = 16129817 }}</ref>
 
*The main pathophysiological mechanism behind [[renal artery stenosis]] is reduction in renal blood flow
*Secondary to [[renal artery stenosis]] which stimulates renin release from the juxtaglomerular apparatus through activation of the tubuloglomerular feedback, [[baroreceptor reflex]], and the [[sympathetic nervous system]].
 
*Elevated angiotensin II activities in turn cause elevation of the [[arterial pressure]] and other effects including [[Aldosterone|aldosterone secretion]], sodium retention, and [[left ventricular hypertrophy]] and remodeling.


==Causes==
==Causes==
Renal artery stenosis is most commonly caused by the development of atherosclerotic plaque in the renal arteries (termed atherosclerotic renal artery stenosis). Less frequently, it is caused by fibromuscular dysplasia.
 
*[[Renal artery stenosis]] is most commonly caused by the development of [[atherosclerotic plaque]] in the renal arteries (termed [[atherosclerotic]] renal artery stenosis).
*Less frequently, it is caused by [[fibromuscular dysplasia]].


==Classification==
==Classification==
Renal artery stenosis may be classified according to whether there is unilateral or bilateral involvement of the renal arteries. Additionally, renal artery stenosis is often classified anatomically according to severity of luminal narrowing. The following criteria are used according to most published studies about ARAS.<ref name="pmid8234704">{{cite journal| author=Kliewer MA, Tupler RH, Carroll BA, Paine SS, Kriegshauser JS, Hertzberg BS et al.| title=Renal artery stenosis: analysis of Doppler waveform parameters and tardus-parvus pattern. | journal=Radiology | year= 1993 | volume= 189 | issue= 3 | pages= 779-87 | pmid=8234704 | doi=10.1148/radiology.189.3.8234704 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=8234704 }} </ref><ref name="pmid2243982">{{cite journal| author=Desberg AL, Paushter DM, Lammert GK, Hale JC, Troy RB, Novick AC et al.| title=Renal artery stenosis: evaluation with color Doppler flow imaging. | journal=Radiology | year= 1990 | volume= 177 | issue= 3 | pages= 749-53 | pmid=2243982 | doi=10.1148/radiology.177.3.2243982 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=2243982 }} </ref>


{| border="1" style="border-collapse:collapse; text-align:center; font-size:120%;" cellpadding="5" align="center" width="300px"
*[[Renal artery stenosis]] may be classified according to whether there is unilateral or bilateral involvement of the [[renal arteries]].
| bgcolor="#ff9a69" align="center" |'''Severity'''|| bgcolor="#ff9a69" align="center" |'''Luminal Narrowing'''
 
|-
*Additionally, [[renal artery stenosis]] is classified anatomically according to the severity of luminal narrowing.
| bgcolor="#f3f3f3" |Normal
|0%
|-
| bgcolor="#f3f3f3" |Mild
|1-49%
|-
| bgcolor="#f3f3f3" |Moderate
|50-69%
|-
| bgcolor="#f3f3f3" |Severe
|70-99%
|-
| bgcolor="#f3f3f3" |Occluded
|100%
|}


To note, some studies have different classification criteria than those listed above, with "mild disease" starting after 50% of luminal narrowing. Such classification remains coherent with the definition of ARAS as narrowing > 50%.<ref name="pmid21719621">{{cite journal| author=Lao D, Parasher PS, Cho KC, Yeghiazarians Y| title=Atherosclerotic renal artery stenosis--diagnosis and treatment. | journal=Mayo Clin Proc | year= 2011 | volume= 86 | issue= 7 | pages= 649-57 |pmid=21719621 | doi=10.4065/mcp.2011.0181 | pmc=PMC3127560 |url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=21719621 }} </ref>
*The following criteria are used according to most published studies about ARAS.


Another classification is based on hemodynamic function in RAS. This classification simply differentiates between hemodynamically insignificant RAS (< 75% stenosis) and hemodynamically significant RAS (> 75% stenosis).<ref name="pmid15114537">{{cite journal| author=Kidney Disease Outcomes Quality Initiative (K/DOQI)| title=K/DOQI clinical practice guidelines on hypertension and antihypertensive agents in chronic kidney disease. | journal=Am J Kidney Dis | year= 2004 | volume= 43 | issue= 5 Suppl 1 | pages= S1-290 | pmid=15114537 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15114537 }} </ref>
*To note, some studies have different classification criteria than those listed above, with "mild disease" starting after 50% of luminal narrowing. Such classification remains coherent with the definition of ARAS as narrowing > 50%.
*Another classification is based on hemodynamic function in [[Renal artery stenosis|RAS]]. This classification simply differentiates between hemodynamically insignificant [[Renal artery stenosis]] (< 75% stenosis) and hemodynamically significant [[Renal artery stenosis]] (> 75% stenosis).


==Epidemiology and Demographics==
==Epidemiology and Demographics==
Atherosclerotic renal artery stenosis (ARAS) is considered a disease of the elderly. The true prevalence of ARAS has not been reliably determined and prevalence rates present so far may in fact be an underestimate or an overestimate of the true prevalence due to the varying selection criteria in different studies. The prevalence of ARAS increases substantially among patients with cardiovascular co-morbidities, such as diabetes mellitus, dyslipidemia, essential hypertension, and known coronary or peripheral artery disease.
 
*Atherosclerotic [[renal artery stenosis]] (ARAS) is considered a disease of the elderly.
 
*The true prevalence of ARAS has not been reliably determined and [[prevalence]] rates present so far may in fact be an underestimate or an overestimate of the true prevalence due to the varying selection criteria in different studies.
 
*The prevalence of ARAS increases substantially among patients with [[cardiovascular]] co-morbidities, such as [[diabetes mellitus]], [[dyslipidemia]], [[essential hypertension]], and known coronary or [[peripheral artery disease]].


==Risk Factors==
==Risk Factors==
Risk factors for ARAS, per se, are poorly studied. The most commonly associated risk factors are those similar to other types of atherosclerosis, such as advanced age, dyslipidemia, diabetes mellitus, smoking, and hypertension.
 
*Risk factors for ARAS, per se, are poorly studied. The most commonly associated risk factors are:
**[[Atherosclerosis]]
**Advanced age
**[[Dyslipidemia]]
**[[Diabetes mellitus]]
**[[Smoking]]
**[[Hypertension]]


==Diagnosis==
==Diagnosis==
Non-invasive diagnosis is the first line for the screening of ARAS. Doppler ultrasonography, CTA, and MRA may all be used to diagnose ARAS. The invasive diagnostic technique, such as renal angiography, is considered the gold standard for diagnosis and may be used when concomitant catheterizations are needed or when previously performed non-invasive techniques yielded equivocal results.


[[Renal artery stenosis diagnostic criteria|Diagnostic Criteria]] | [[Renal artery stenosis history and symptoms|History and Symptoms]] | [[Renal artery stenosis physical examination|Physical Examination]] | [[Renal artery stenosis x ray|X Ray]] | [[Renal artery stenosis CT|CT]] | [[Renal artery stenosis MRI|MRI]] | [[Renal artery stenosis ultrasound|Echocardiography or Ultrasound]]
*Non-invasive diagnosis is the first line for the screening of [[Renal artery stenosis|ARAS]].
 
*[[Doppler ultrasonography]], [[CTA]], and [[MRA]] may all be used to diagnose ARAS.
 
*The invasive diagnostic technique, such as [[renal angiography]], is considered the gold standard for diagnosis and may be used when
*Concomitant [[Catheterization|catheterizations]] are needed or when previously performed non-invasive techniques yielded equivocal results.
 
==Treatment==
==Treatment==
Medical therapy is considered the first line of management for patients with ARAS. Several anti-hypertensive medications have proven to be efficacious in ARAS patients. According to the 2013 ACC/AHA Guidelines for the Management of PAD, ACE-I and CCB may be used in patients with RAS because they have an effect on both lowering BP and delaying the renal disease. Other blood pressure-lowering medications include beta-blockers, hydrazine, and chlorothiazide. Although ARBs may be used as well, they still have level B evidence for use in ARAS because trials have not been conducted on the use of ARBs in such patients.


Angioplasty and stent implantation were previously recommended by the 2013 ACC/AHA Guidelines. However, emerging data from the CORAL trial showed that although there are high technical success rates with angioplasty/stenting, the clinical endpoints are inconsistently and modestly modified. Therefore, raising the suspicion that PRI (percutaneous renal interventions) can incur substantial costs without a significant public health advantage<, ref, name="pmid24245566">{{cite journal| author=Cooper CJ, Murphy TP, Cutlip DE, Jamerson K, Henrich W, Reid DM et al.| title=Stenting and medical therapy for atherosclerotic renal artery stenosis. | journal=N Engl J Med | year= 2014 | volume= 370 | issue= 1 | pages= 13-22 | pmid=24245566 |doi=10.1056/NEJMoa1310753 | pmc= |url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=24245566  }}</ref>
*Medical therapy is considered the first line of management for patients with [[ARAS]].


Vascular reconstruction of the renal arteries may be indicated in a small minority of patients. However, surgical reconstruction is associated with complications and carries a 5-15% for surgical re-intervention.  
*Several [[anti-hypertensive]] [[medications]] have proven to be efficacious in ARAS patients.


[[Renal artery stenosis medical therapy|Medical Therapy]] [[Renal artery stenosis angioplasty and stenting|Angioplasty and Stenting]] | [[Renal artery stenosis surgery|Surgery]] | [[Renal artery stenosis primary prevention|Primary Prevention]] | [[Renal artery stenosis secondary prevention|Secondary Prevention]] | [[Renal artery stenosis cost-effectiveness of therapy|Cost-Effectiveness of Therapy]] | [[Renal artery stenosis future or investigational therapies|Future or Investigational Therapies]]
*According to the 2013 ACC/AHA Guidelines for the Management of [[PAD]], [[ACE-I]] and [[CCB]] may be used in [[patients]] with RAS because they have an effect on both lowering BP and delaying the [[renal disease]].


==Case Studies==
*Other [[blood pressure]]-lowering medications include [[beta-blockers]], [[hydrazine]], and [[chlorothiazide]].


*[[Renal artery stenosis case study one|Case #1]]
*Although [[ARBs]] may be used as well, they still have level B evidence for use in ARAS because trials have not been conducted on the use of ARBs in such patients.
 
*[[Angioplasty]] and [[stent]] implantation were previously recommended by the 2013 ACC/AHA Guidelines. However, emerging data from the [[CORAL]] trial showed that although there are high technical success rates with [[angioplasty]]/[[stenting]], the clinical endpoints are inconsistently and modestly modified. Therefore, raising the suspicion that PRI ([[percutaneous renal interventions]]) can incur substantial costs without a significant public health advantage
 
*Vascular reconstruction of the [[renal arteries]] may be indicated in a small minority of patients. However, surgical reconstruction is associated with complications and carries a 5-15% for surgical re-intervention.


==Related Chapters==
==Related Chapters==
Line 76: Line 93:
*[[Uremia]]
*[[Uremia]]


==External Links==
==Case studies==
 
{{Circulatory system pathology}}
{{Nephrology}}


==References==
==References==

Latest revision as of 07:33, 8 April 2021

Renal artery stenosis Microchapters

Home

Patient Information

Overview

Historical Perspective

Classification

Pathophysiology

Causes

Differentiating Renal artery stenosis from other Diseases

Epidemiology and Demographics

Risk Factors

Screening

Natural History, Complications and Prognosis

Diagnosis

Diagnostic Study of Choice

History and Symptoms

Physical Examination

Laboratory Findings

Electrocardiogram

X-ray

Echocardiography and Ultrasound

CT scan

MRI

Other Imaging Findings

Other Diagnostic Studies

Treatment

Medical Therapy

Interventions

Surgery

Primary Prevention

Secondary Prevention

Cost-Effectiveness of Therapy

Future or Investigational Therapies

Case Studies

Case #1

Renal artery stenosis overview On the Web

Most recent articles

Most cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of Renal artery stenosis overview

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on Renal artery stenosis overview

CDC on Renal artery stenosis overview

Renal artery stenosis overview in the news

Blogs on Renal artery stenosis overview

Directions to Hospitals Treating Renal artery stenosis

Risk calculators and risk factors for Renal artery stenosis overview

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Shivam Singla, M.D.[2]

Overview

Pathophysiology

Causes

Classification

  • Additionally, renal artery stenosis is classified anatomically according to the severity of luminal narrowing.
  • The following criteria are used according to most published studies about ARAS.
  • To note, some studies have different classification criteria than those listed above, with "mild disease" starting after 50% of luminal narrowing. Such classification remains coherent with the definition of ARAS as narrowing > 50%.
  • Another classification is based on hemodynamic function in RAS. This classification simply differentiates between hemodynamically insignificant Renal artery stenosis (< 75% stenosis) and hemodynamically significant Renal artery stenosis (> 75% stenosis).

Epidemiology and Demographics

  • The true prevalence of ARAS has not been reliably determined and prevalence rates present so far may in fact be an underestimate or an overestimate of the true prevalence due to the varying selection criteria in different studies.

Risk Factors

Diagnosis

  • Non-invasive diagnosis is the first line for the screening of ARAS.
  • The invasive diagnostic technique, such as renal angiography, is considered the gold standard for diagnosis and may be used when
  • Concomitant catheterizations are needed or when previously performed non-invasive techniques yielded equivocal results.

Treatment

  • Medical therapy is considered the first line of management for patients with ARAS.
  • According to the 2013 ACC/AHA Guidelines for the Management of PAD, ACE-I and CCB may be used in patients with RAS because they have an effect on both lowering BP and delaying the renal disease.
  • Although ARBs may be used as well, they still have level B evidence for use in ARAS because trials have not been conducted on the use of ARBs in such patients.
  • Angioplasty and stent implantation were previously recommended by the 2013 ACC/AHA Guidelines. However, emerging data from the CORAL trial showed that although there are high technical success rates with angioplasty/stenting, the clinical endpoints are inconsistently and modestly modified. Therefore, raising the suspicion that PRI (percutaneous renal interventions) can incur substantial costs without a significant public health advantage
  • Vascular reconstruction of the renal arteries may be indicated in a small minority of patients. However, surgical reconstruction is associated with complications and carries a 5-15% for surgical re-intervention.

Related Chapters

Case studies

References