Aortic regurgitation (AR) is the diastolic flow of blood from the aorta into the left ventricle (LV). Regurgitation is because of incompetence of the aortic valve or any type of disturbance of the valvular apparatus (eg, leaflets, annulus that the aorta) causing the diastolic circulation of blood right into the left ventricular chamber. (See Pathophysiology and also Etiology.)

Valvular abnormalities the may result in AR have the right to be brought about by the adhering to (see Etiology, Presentation, and Workup):


Abnormalities the the ascending aorta, in the lack of valve pathology, may also cause AR. Together abnormalities may happen with the adhering to conditions:


Aortic regurgitation may be a chronic disease process or it may occur acutely, presenting together heart failure. <2> The most common cause of chronic aortic regurgitation used to be rheumatic heart disease, but presently that is most typically caused by bacter endocarditis. <3> In emerged countries, it is led to by dilation that the ascending aorta (eg, aortic source disease, aortoannular ectasia). (See Presentation and also Workup.)


Three fourths of patient with far-reaching aortic regurgitation endure 5 years after diagnosis; half survive for 10 years. Patients through mild come moderate regurgitation make it through 10 year in 80-95% of the cases. Mean survival ~ the onset of congestive heart fail (CHF) is much less than 2 years. (See Prognosis, Treatment, and Medication.)


Acute aortic regurgitation is associated with significant morbidity, which deserve to progress native pulmonary edema to refractory heart failure and also cardiogenic shock.

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Patient education

The 2014 American college of Cardiology/American heart Association (ACC/AHA) guidelines because that valvular love disease, consisting of for AR, are easily accessible to the general public online because that free. <4> Additionally, educational and support organizations, such as the nationwide Marfan structure and the Bicuspid Aortic Foundation, exist for numerous of the underlying conditions.



Incompetent closure that the aortic valve can result from intrinsic condition of the leaflets, cusp, conditions of the aorta, or trauma. Diastolic reflux v the aortic valve can lead to left ventricular volume overload. An increase in systolic stroke volume and low diastolic aortic press produces an enhanced pulse pressure. The clinical indicators of AR are led to by the forward and backward flow of blood throughout the aortic valve, top to boosted stroke volume. <5>


The severity of AR is dependency on the diastolic regurgitant valve area, the diastolic press gradient in between the aorta and also LV, and the term of diastole.


The pathophysiology the AR relies on whether the AR is acute or chronic. In acute AR, the LV walk not have time to dilate in an answer to the volume load, whereas in chronic AR, the LV might undergo a series of adaptive (and maladaptive) changes.


Acute aortic regurgitation

Acute AR of far-ranging severity leader to boosted blood volume in the LV throughout diastole. The LV does no have enough time come dilate in response to the sudden rise in volume. As a result, LV end-diastolic pressure boosts rapidly, causing rise in pulmonary venous pressure and also altering coronary flow dynamics. Together pressure increases throughout the pulmonary circuit, the patient develops dyspnea and pulmonary edema. In severe cases, heart failure might develop and potentially deteriorate to cardiogenic shock. Reduced myocardial perfusion may cause myocardial ischemia.


Early surgical treatment should be considered (particularly if AR is as result of aortic dissection, in which situation surgery need to be perform immediately).


Chronic aortic regurgitation

Chronic AR reasons gradual left ventricular volume overload that leads to a collection of compensatory changes, consisting of LV enlargement and also eccentric hypertrophy. LV dilation occurs v the enhancement of sarcomeres in series (resulting in longer myocardial fibers), as well as through the rearrangement of myocardial fibers. Together a result, the LV becomes bigger and more compliant, with greater capacity to provide a large stroke volume that can compensate for the regurgitant volume. The result hypertrophy is essential to accommodate the increased wall surface tension and stress that an outcome from LV dilation (Laplace law).


During the beforehand phases that chronic AR, the LV ejection fraction (EF) is common or even increased (due come the increased preload and also the Frank-Starling mechanism). Patients may remain asymptomatic throughout this period. Together AR progresses, LV enlargement surpasses preload make reservation on the Frank-Starling curve, through the EF falling to normal and then subnormal levels. The LV end-systolic volume rises and is one indicator of progressive myocardial dysfunction.


Eventually, the LV get its maximal diameter and also diastolic pressure begins to rise, bring about symptoms (dyspnea) that might worsen throughout exercise. Enhancing LV end-diastolic push may also lower coronary perfusion gradients, causing subendocardial and also myocardial ischemia, necrosis, and also apoptosis. Grossly, the LV slowly transforms indigenous an elliptical come a spherical configuration.



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Etiology


Acute aortic regurgitation

Infective endocarditis may lead to devastation or perforation of the aortic valve leaflet. A bulky vegetation can likewise interfere with proper coaptation of the valve leaflets or bring about frank prolapse or disruption the a leaflet (flail leaflet). <3>


Another reason of acute AR, chest trauma, may cause a tear in the ascending aorta and also disruption the the aortic valve support apparatus. V the advancement and clinical adoption of transcatheter aortic valve instead of (TAVR) techniques, post-TAVR AR has arised as a common and potentially important cause of both acute and chronic AR. <6> AR may additionally develop as a complication the left ventricular assist maker (LVAD) implantation. <7>


In acute ascending aortic dissection (type A), the retrograde proximal dissection undermines the suspensions the the aortic valve leaflets. Differing levels the aortic valve malcoaptation and also prolapse occur. Prosthetic valve malfunction can additionally lead come AR.


Chronic aortic regurgitation

Bicuspid aortic valve is the most typical congenital lesion the the human heart. Although the leads much more often to gradual aortic stenosis 보다 to AR, it is nevertheless the most common reason of isolated AR requiring aortic valve surgery. In patients through bicuspid aortic valve, an connected aortopathy may be present, bring about aortic dilation and/or dissection that intensifies the AR. <8> existing American university of Cardiology/American heart Association (ACC/AHA) indict recommend consideration of surgical intervention when the aortic diameter reaches 5.0 cm (or 4.5 cm in patient who room undergoing cardiac surgical procedure for reasons various other than aortic enlargement). <9>


Certain load loss medications, such together fenfluramine and dexfenfluramine (commonly described as Phen-Fen), might induce degenerative valvular alters that an outcome in chronic AR.


Rheumatic fever, a common reason of AR in the an initial half of the 20th century, has end up being less typical in the united States, although it remains prevalent in some immigrant populations. Fibrotic changes cause thickening and also retraction that the aortic valve leaflets, result in central valvular regurgitation. Leaflet combination may occur, bring about concurrent aortic stenosis. Linked rheumatic mitral valve condition is virtually always present.


Ankylosing spondylitis often causes an aortitis, which most commonly involves the aortic root, with linked AR. <10> Further extension of the subaortic fibrotic procedure into the intraventricular septum may result in conduction device disease. Coronary and much more distal aortic abnormalities are likewise seen in this condition.


Behçet condition causes cardiac symptom in less than 5% the patients, yet potential findings incorporate proximal aortitis v AR, and coronary artery disease. <11>


Giant cabinet arteritis is a systemic vasculitis that frequently affects the extracranial branches the the carotid artery but may also cause aortic inflammation and also AR (as well as coronary artery an illness and LV dysfunction). <12>


Rheumatoid arthritis uncommonly causes granulomatous nodules to type within the aortic valve leaflets. In rarely cases, this may result in clinical AR, although the is an ext commonly one incidental finding postmortem. <13>


Systemic lupus erythematosus can reason valvular fibrosis and consequent dysfunction, consisting of AR. <14> Lupus is likewise associated through Libman-Sacks endocarditis, causing sterile, verrucous valvular vegetations that can cause AR. <15, 16>


Takayasu arteritis, in enhancement to having aortic valvular (and coronary) involvement, can produce an aortitis. The aortitis may rise the risk of prosthetic valve detachment, leading part to advocate for concurrent aortic root replacement in patients undergoing valve surgery. <17>


Whipple disease has to be reported in the literature in association through AR or aortic valve endocarditis. <18>


Connective organization disorders that deserve to cause far-reaching AR encompass the following:


Floppy aortic valve


Aortic valve prolapse


Sinus the Valsalva aneurysm


Aortic annular fistula



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Epidemiology


Occurrence in the unified States

Although rheumatic heart an illness is overall the most common reason of AR worldwide, congenital and also degenerative valve abnormalities are the many common reason in the united States, with the age of detection peaking at 40-60 years. Estimates of the prevalence of AR of any kind of severity selection from 2-30%, but only 5-10% of patients with AR have actually severe disease, bring about an in its entirety prevalence of significant AR of much less than 1% in the general population. <19>


In the Framingham examine (with an original cohort of 5209 patients age 28-62 y and second cohort that 5124 patients), AR of any severity was uncovered in 13% that men and 8.5% the women. <20> Prevalence and also severity enhanced with age; once stratified by decades of life, AR of middle or higher severity was checked out in less than 1% of patients in every strata younger than 70 years.


International occurrence

The prevalence of AR internationally is not well known. However, the international prevalence that underlying problems has been explained elsewhere. Because that example, rheumatic heart condition remains highly prevalent in many Asian, middle Eastern, and also North afri countries. <21>


Race-, sex-, and age-related demographics

The prevalence of AR appears to be similar across racial populaces in the unified States, although worldwide there is far-ranging variation in the prevalence of predisposing conditions, such together rheumatic heart disease. <21>


AR is seen more commonly in men than in women. In the cohort native the Framingham study, AR was discovered in 13% the men and 8.5% the women. <20> The greater prevalence the AR in men might reflect, in part, the preponderance of basic conditions, such together Marfan syndrome <22> or bicuspid aortic valve, in males. <23>


Chronic aortic regurgitation often starts in patients once they space in their late 50s and also is recorded most generally in patients older 보다 80 years. In general, the prevalence and also severity of AR rise with age, although significant chronic AR is uncommon prior to age 70 years. <20> However, over there are plenty of exceptions to this observation. Patients v bicuspid aortic valve and, especially, those through Marfan syndrome have tendency to current much earlier. <22, 23>


Following TAVR

TAVR has emerged as vital treatment for aortic valve disease, primarily aortic stenosis. Paravalvular AR is common after TAVR, emerging to some level in approximately 70% of cases and being graded together moderate or significant in about 15%. <6>



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Prognosis


The prognosis for patients with major AR counts on the existence or absence of LV dysfunction and symptomsIn asymptomatic patients v normal EF, the complying with has been found:


Rate of development to symptoms or LV dysfunction - less than 6% every year


Rate of progression to asymptomatic LV dysfunction - much less than 3.5% every year


Rate that sudden death - much less than 0.2% per year


In asymptomatic patients with reduced EF, the price of development to symptoms is greater than 25% per year, while in symptomatic patients, the mortality price is over 10% every year.


The strongest predictors that outcome space echocardiographic parameters (EF and also LV end-systolic dimension), underscoring the an essential role of serial echocardiography in the management of patient with severe AR.


Exercise LV end-systolic volume table of contents (LVESVi) may have prognostic worth as an independent predictor that outcomes inin patients with asymptomatic center or serious AR. <24>


Severe acute AR, if left untreated, is most likely to command to considerable morbidity and also mortality from one of two people the underlying reason (typically infective endocarditis or aortic dissection) or indigenous hemodynamic decompensation the the LV.


Potential symptom in patient with severe chronic AR encompass progressive LV dysfunction and also dilation, congestive love failure, myocardial ischemia, arrhythmia, and sudden death. Extr complications may arise as a an outcome of the patient"s underlying condition (such as aortic root dissection in a patient v a bicuspid aortic valve and also a severely dilated aortic root).


Morbidity and mortality

Severe acute AR dead a an extremely high short-term price of morbidity and also mortality fan to the imposition that a significantly increased regurgitant volume ~ above a fairly noncompliant LV. Enhanced LV end-diastolic pressure leads to elevated left atrial and also pulmonary pressures through resulting pulmonary edema, and also decreased coronary perfusion gradients that potentially can cause myocardial ischemia and even sudden cardiac death. In most cases, at an early stage (if no emergent) surgical treatment is warranted.


Severe chronic AR often tends to follow a an ext gradual clinical course. This is typically characterized initially by a long, reasonably asymptomatic period. However, as soon as symptoms ensue, the patient"s clinical status may deteriorate reasonably rapidly. Thus, existing guidelines recommend operation intervention before symptoms develop, usually based on echocardiographic parameters.

See more: The Distance Along A Circle Between Two Points On The Circle S


With conservative (medical) monitoring of significant chronic AR, the linearized yearly prices of major events have been approximated as complies with <25> :


Death from any kind of cause - 4.7%


Congestive heart failure - 6.2%


Aortic valve surgery - 14.6%


The existence of symptoms has been uncovered to suspect yearly mortality risk, as follows:


Asymptomatic - 2.8%


New York heart Association (NYHA) course I - 3.0%


NYHA class II - 6.3%


NYHA class III-IV - 24.6%


Although these types of data imply that a symptom-triggered method to surgical treatment may it is in feasible, multiple researches have presented that, as stated earlier, the most essential predictors the mortality (and that postoperative LV function) are not symptoms yet 2 critical echocardiographic parameters; special, LV ejection portion and LV end-systolic dimension.


Risk that coronary artery disease


A examine by Atalar et al uncovered that in patients through rheumatic valve disease, the pervasiveness of AR was inversely proportional to the pervasiveness of far-ranging coronary artery disease. The investigators, who carried out a retrospective evaluation of an ext than 1000 patients v rheumatic valve disease, additionally found that, while the presence of coronary artery condition was particularly low in patients with AR, it to be unusually high in those through aortic stenosis. <26>


Following TAVR


Multiple research studies have shown that the visibility of greater than soft AR following TAVR is linked with substantially increased morbidity and also mortality. Contrasted with patient who have no or gentle AR, patients through moderate or major AR after TAVR may have an ext than twin the risk of mortality. <6>



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Clinical Presentation
recommendations

Braunwald E. Heart Disease: A Textbook that Cardiovascular Medicine. 10th ed. Philadelphia, Pa: Elsevier Saunders; 2015.


Media collection
Aortic regurgitation. Color Doppler echocardiogram.
Aortic regurgitation. Doppler echocardiographic signals might be the review to evaluate the severity the disease.
Aortic regurgitation. Two-dimensional (2D) color Doppler echocardiography.
Aortic regurgitation. Aortic-root angiography mirrors regurgitation of comparison material into the left ventricle (LV).
Aortic regurgitation. Chest radiograph in a patient v aortic dissection and acute aortic regurgitation mirrors a cardiac silhouette of basically normal dimension.
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Tables
Table 1: Frequency of Followup the Patients with Aortic Regurgitation.

LVESD (mm)

LVEDD (mm)

Dimensions

Clinical Evaluation

Echocardiogram

55

>75

Surgery recommended


Table 2.Guidelines because that Aortic Regurgitation Surgical treatment

Aortic valve instead of (AVR) indications

Note: STS guidelines introduce “valve replacement or valve repair”

AHA/ACC (2014) <4>

ESC/EACTS (2012) <42>

STS (2013) <9>

Symptomatic major AR

Class I

Class I

Class I

Asymptomatic chronic significant AR and also left ventricular ejection portion (LVEF) ≤50%

Class I

Class I

Class I

Severe AR as soon as undergoing various other cardiac surgery

Class I

Class I

Class I

Asymptomatic severe AR with normal LVEF (≥50%) however with serious LV dilation (LVESD >50mm)

Class IIa-Reasonable

Class IIa-Reasonable

Class IIa-Reasonable

Moderate AR when undergoing other cardiac surgery

Class IIa-Reasonable

Class IIb-Consider

Asymptomatic severe AR and normal LVEF (≥50%) but with gradual severe LV dilation (LVEDD>65 mm) if surgical threat is low

Class IIb-Consider

Class IIa-Reasonable

Class IIb-Consider

Not suggested for asymptomatic patients v mild, moderate, or serious AR and normal LV systolic role at rest as soon as the degree of LV dilation is not moderate or severe