Approach Considerations
In severe acute aortic regurgitation (AR), surgical intervention is usually indicated, but the patient may be supported medically with dobutamine to augment cardiac output and shorten diastole and with sodium nitroprusside to reduce afterload in hypertensive patients.
Vasodilator therapy may be used on an inpatient or outpatient basis under conditions described in the current ACC/AHA guidelines. [4]
All patients with an artificial heart valve should receive antibiotic prophylaxis prior to dental procedures. For antithrombotic therapy, all patients with an artificial heart valve should receive daily aspirin, and many should also receive oral anticoagulation therapy. [4]
Although diuretics, nitrates, and digoxin are sometimes used to help control symptoms in patients with AR, not enough data in the clinical literature justify routinely recommending or discouraging these therapies. Also, no data support drug therapy of any class in patients with less than severe AR. [4]
Intra-aortic balloon counterpulsation, which can be used to provide temporary mechanical circulatory support, is contraindicated in patients with severe AR.
Inpatient/outpatient care
Inpatient care is required for most patients with severe acute aortic regurgitation (AR), particularly patients with symptoms or evidence of hemodynamic decompensation. Patients with severe chronic AR may be followed as inpatients or outpatients, depending on the stage of their disease and severity of their symptoms and LV dysfunction.
Transfer
For patients who are hospitalized for severe AR in facilities without appropriate cardiovascular and surgical expertise, transfer may be justified to optimize clinical outcomes. For outpatients with stable but severe AR, longitudinal care by a cardiologist with appropriate expertise is recommended.
Emergency Department Care
General requirements in emergency department care for patients with AR include the following:
-
Provide adequate airway management
-
Intubate when necessary
-
Consider prompt surgical intervention in acute AR
Acute aortic regurgitation
Administer a positive inotrope (eg, dopamine, dobutamine) and a vasodilator (eg, nitroprusside). Administration of vasodilators may be appropriate to improve systolic function and to decrease afterload.
The administration of cardiac glycosides (eg, digoxin) for rate control may in rare cases be necessary. Avoid beta-blockers in the acute setting.
Chronic aortic regurgitation
Consider antibiotic prophylaxis for patients with endocarditis when performing procedures likely to result in bacteremia. The administration of pressors and/or vasodilators may be appropriate.
Vasodilator Therapy
In severe chronic AR, vasodilator therapy may be used in select conditions to reduce afterload in patients with systolic hypertension, in order to minimize wall stress and optimize LV function. In normotensive patients, however, vasodilator therapy is not likely to reduce regurgitant volume (preload) significantly and thus may not be of clinical benefit. [34]
Antibiotic Prophylaxis
The prophylactic use of antibiotics prior to dental procedures is no longer routinely recommended for all patients with AR. [4] However, select patient groups for whom prophylactic antibiotic therapy prior to dental procedures may be reasonable include the following:
-
Patients with prosthetic material in their heart - Such as an artificial valve or a valve repaired with prosthetic material
-
Patients with prior infective endocarditis
-
Patients who, following cardiac transplantation, have valve regurgitation due to a structurally abnormal valve
-
Patients with congenital heart disease (CHD) who meet any of the following criteria: (1) cyanotic CHD that has not been repaired or has been incompletely repaired (including patients with palliative shunts and conduits); (2) repaired CHD using prosthetic material, for the first 6 months postprocedurally (ie, prior to endothelialization of the material); or (3) repaired CHD but the patient is at risk for inhibited endothelialization (ie, with residual defects at or adjacent to the site of the prosthetic material)
Valve Surgery
Surgical treatment of AR usually requires replacement of the diseased valve with a prosthetic valve, although valve-sparing repair is increasingly possible with advances in surgical technique and technology. Such improvements have also enabled many patients, even those with severe LV dysfunction, to undergo valve surgery instead of cardiac transplantation. [35, 36, 37] Salih et al recommend early surgical closure for patients with VSD and AV prolapse for better post-repair outcomes and prevention of AR progression. [38]
In a retrospective analysis (995-2012), De Meester et al compared the prognosis of aortic valve (AV) repair to that of AV replacement (AVR) using a propensity score analysis and found similar operative mortality (2% vs 5%, respectively). [39] However, on Kaplan-Meier survival analysis, there was a significantly better overall 9-year survival after AV repair (87%) than after AVR (60%). Cox proportional survival analysis showed that treatment selection was an independent predictor of postoperative survival. [39] The investigators suggest these findings indicate that AVR should probably the preferred surgical intervention for correction of aortic regurgitation as feasible.
Mechanical versus bioprosthetic aortic valves
For patients undergoing aortic valve replacement, careful consideration should be given to the relative risks and benefits of mechanical versus bioprosthetic valves.
Traditionally, mechanical valves have been thought to be more durable, but they require long-term anticoagulation therapy with warfarin due to an increased risk of thrombosis. The use of bioprosthetic valves avoids the need for long-term warfarin, but they carry a greater risk of long-term deterioration and a need for reoperation. [40]
In some cases, the choice of valve is apparent; eg, a homograft is often preferred to a mechanical valve in the setting of active infective endocarditis.
While further discussion is beyond the scope of this article, the reader is referred to the current ACC/AHA guidelines, which include major criteria for aortic valve selection, as well as recommendations for antithrombotic therapy (including aspirin for all prosthetic valve recipients along with long-term anticoagulation with warfarin for selected patients). [4]
Transcatheter aortic valve replacement as a treatment
Transcatheter aortic valve replacement (TAVR) has emerged as an important therapy for aortic stenosis (with or without AR) and now is being evaluated for use in patients with predominantly AR. TAVR involves the implantation of a bioprosthetic aortic valve using a catheter that is inserted peripherally, typically through the femoral artery, and implanted without requiring a median sternotomy (ie, without “open heart surgery”). Initial reports are promising but further studies are needed before TAVR becomes clinically available. [41]
TAVR as a cause
Management of AR that is the result of TAVR, typically following its use for aortic stenosis, depends on the severity and hemodynamic impact of the AR. Once a determination is made that the patient is likely to benefit from intervention, potential corrective measures (each of which carries unique risks include the following: [6]
-
Balloon postdilation - In cases of valve malapposition or underexpansion
-
Snare technique - Use of a snare catheter to reposition a deeply implanted valve
-
Interventional closure - Use of a vascular plug to seal a localized AR jet
-
Valve-in-valve implantation - Deployment of a second prosthetic valve
Diet and Activity
No specific dietary recommendations exist pertaining purely to AR. However, for patients with hypertension or hypervolemia (including peripheral edema or other heart failure symptoms), salt restriction may provide significant clinical benefit.
Current recommendations regarding activity in patients with AR are based mostly on expert opinion, because there is a paucity of clinical trial data, including no convincing evidence to suggest that even strenuous periodic exercise worsens LV function in patients with AR.
Patients who are asymptomatic and have a normal EF may safely participate in normal daily activities as well as mild exercise and some forms of competitive exercise. However, isometric exercise is discouraged. The short-term safety of more vigorous exercise (eg, competitive athletics) may be estimated through the use of stress testing at a comparable level of exertion, but the long-term effects of such exercise are not known.
Long-Term Monitoring
Asymptomatic patients with severe chronic AR require ongoing clinical surveillance with periodic echocardiography. This is because significant LV dysfunction in many cases may arise even before the patient becomes symptomatic.
After the initial study, clinical evaluation and a repeat echocardiogram are recommended in 3 months. The recommended frequency of subsequent follow-up evaluations is based on the stability of the LVESD and LVEDD, as follows:
-
For patients with an end-systolic dimension (ESD) below 45 mm or an end-diastolic dimension (EDD) below 60 mm and stable dimensions, clinical evaluation is recommended every 6-12 months and repeat echocardiography is recommended every 12 months
-
For patients with an ESD below 45 mm or an EDD below 60 mm and increasing dimensions, clinical evaluation and repeat echocardiography are recommended in 3 months
-
For patients with an ESD of 45-50 mm or an EDD of 60-70 mm and stable dimensions, clinical evaluation is recommended every 6 months and repeat echocardiography is recommended every 12 months
-
For patients with an ESD of 45-50 mm or an EDD of 60-70 mm and increasing dimensions, clinical evaluation and repeat echocardiography are recommended in 3 months
-
For patients with an ESD of 50-55 mm or an EDD of 70-75 mm and stable dimensions, clinical evaluation and repeat echocardiography are recommended every 6 months
-
For patients with an ESD of 50-55 mm or an EDD of 70-75 mm and increasing dimensions, clinical evaluation and repeat echocardiography are recommended in 3 months
-
For patients with an ESD of 55 mm or greater or an EDD of 75 mm or greater, surgery is recommended
Table 1: Frequency of Followup of Patients With Aortic Regurgitation. (Open Table in a new window)
LVESD (mm) |
LVEDD (mm) |
Dimensions |
Clinical Evaluation |
Echocardiogram |
< 45 |
< 60 |
Stable |
6-12 months |
12 months |
< 45 |
< 60 |
Increasing |
3 months |
3 months |
45-50 |
60-70 |
Stable |
6 months |
12 months |
45-50 |
60-70 |
Increasing |
3 months |
3 months |
50-55 |
70-75 |
Stable |
6 months |
6 months |
50-55 |
70-75 |
Increasing |
3 months |
3 months |
>55 |
>75 |
|
Surgery recommended |
|
-
Aortic regurgitation. Color Doppler echocardiogram.
-
Aortic regurgitation. Doppler echocardiographic signals may be reviewed to evaluate the severity of disease.
-
Aortic regurgitation. Two-dimensional (2D) color Doppler echocardiography.
-
Aortic regurgitation. Aortic-root angiography shows regurgitation of contrast material into the left ventricle (LV).
-
Aortic regurgitation. Chest radiograph in a patient with aortic dissection and acute aortic regurgitation shows a cardiac silhouette of essentially normal dimension.
Tables
LVESD (mm) |
LVEDD (mm) |
Dimensions |
Clinical Evaluation |
Echocardiogram |
< 45 |
< 60 |
Stable |
6-12 months |
12 months |
< 45 |
< 60 |
Increasing |
3 months |
3 months |
45-50 |
60-70 |
Stable |
6 months |
12 months |
45-50 |
60-70 |
Increasing |
3 months |
3 months |
50-55 |
70-75 |
Stable |
6 months |
6 months |
50-55 |
70-75 |
Increasing |
3 months |
3 months |
>55 |
>75 |
|
Surgery recommended |
|
Aortic valve replacement (AVR) indications Note: STS guidelines recommend “valve replacement or valve repair” |
AHA/ACC (2014) [4] |
ESC/EACTS (2012) [43] |
STS (2013) [9] |
Symptomatic severe AR |
Class I |
Class I |
Class I |
Asymptomatic chronic severe AR and left ventricular ejection fraction (LVEF) ≤50% |
Class I |
Class I |
Class I |
Severe AR when undergoing other cardiac surgery |
Class I |
Class I |
Class I |
Asymptomatic severe AR with normal LVEF (≥50%) but with severe 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 progressive severe LV dilation (LVEDD >65 mm) if surgical risk is low |
Class IIb-Consider |
Class IIa-Reasonable |
Class IIb-Consider |
Not indicated for asymptomatic patients with mild, moderate, or severe AR and normal LV systolic function at rest when the degree of LV dilation is not moderate or severe |
Class III |
