What is the initial treatment approach for patients with moderate aortic and mitral regurgitation?

Management of Moderate Aortic and Mitral Regurgitation

For patients with moderate aortic and mitral regurgitation, the initial treatment approach is regular clinical surveillance with echocardiographic monitoring every 1-2 years, combined with guideline-directed medical therapy for any concurrent hypertension or heart failure, while reserving surgical intervention for those who develop symptoms, left ventricular dysfunction, or progression to severe disease. 1

Initial Assessment Strategy

Determine the predominant lesion through comprehensive echocardiographic evaluation, as management follows recommendations for the dominant valve pathology when one lesion is clearly more severe than the other. 1 The coexistence of both regurgitant lesions creates incremental pathological consequences beyond either lesion alone—the combined volume overload may lead to symptoms and chamber remodeling earlier than expected with isolated moderate disease. 1

Key Diagnostic Considerations

• Echocardiographic parameters to assess: vena contracta width, effective regurgitant orifice area (EROA), regurgitant volume, left ventricular dimensions (end-diastolic and end-systolic), left ventricular ejection fraction, left atrial size, and pulmonary artery systolic pressure. 1

• Exercise testing should be performed when symptoms seem disproportionate to resting hemodynamic findings, as patients with mixed moderate disease may develop functional limitations at higher flow rates that are not apparent at rest. 1

• Cardiac catheterization with direct pressure measurements may be necessary if noninvasive assessments show discrepancies between symptoms and echocardiographic severity, particularly to evaluate exercise hemodynamics. 1

Medical Management Approach

Blood Pressure Control

• For patients with hypertension (systolic BP >140 mmHg), ACE inhibitors or ARBs are recommended as they reduce afterload and may provide symptomatic improvement in chronic aortic regurgitation. 1

• Beta-blockers have the strongest evidence for moderate to severe primary mitral regurgitation, as they lessen MR severity, prevent deterioration of left ventricular function, and improve survival in asymptomatic patients. 2

• Vasodilator therapy must be used cautiously—while ACE inhibitors and ARBs can reduce MR severity in asymptomatic patients, they can paradoxically worsen regurgitation in specific contexts like mitral valve prolapse or hypertrophic cardiomyopathy. 2

Heart Failure Management

• If symptoms of heart failure develop (NYHA class II or higher), initiate guideline-directed medical therapy including ACE inhibitors/ARBs (or sacubitril/valsartan), beta-blockers, and mineralocorticoid receptor antagonists. 1

• Diuretics should be used for symptomatic relief of fluid overload and congestion. 1, 3

• Cardiac resynchronization therapy (CRT) should be performed if heart failure criteria are met and there is appropriate indication based on QRS duration and morphology. 1

Surveillance Protocol

Monitoring Frequency

• Moderate aortic regurgitation requires echocardiographic follow-up every 1-2 years in asymptomatic patients with normal left ventricular function. 1

• Moderate mitral regurgitation requires clinical evaluation every 6-12 months with annual echocardiography. 1, 4

• For mixed moderate disease, adopt the more frequent surveillance schedule (every 1-2 years) given the potential for accelerated progression due to combined volume overload. 1

Parameters Requiring Closer Monitoring

• Repeat imaging at 3-6 month intervals if there is apparent significant fall in ejection fraction, significant changes in left ventricular dimensions, or clinical deterioration. 1

• Monitor specifically for: progression of regurgitation severity, development of symptoms (dyspnea, decreased exercise tolerance, palpitations), left ventricular enlargement (LVESD approaching 40 mm for MR or 50 mm for AR), declining ejection fraction (approaching 60% for MR or 55% for AR), new-onset atrial fibrillation, and development of pulmonary hypertension. 1, 3, 4

Indications for Surgical Referral

Symptomatic Patients

Valve intervention should be considered when symptoms develop that are attributable to the valve disease with supportive clinical findings including objective evidence of functional limitation (severely reduced peak oxygen consumption) or significantly elevated atrial/ventricular pressures on exercise hemodynamic studies. 1

Asymptomatic Patients with Ventricular Changes

• For aortic regurgitation: surgical referral is indicated if LVEF falls to ≤55% (or ≤50% per some guidelines) or LVESD exceeds 50 mm (or 25 mm/m²). 1

• For mitral regurgitation: surgical referral is indicated if LVEF falls to <60% or LVESD reaches ≥40 mm. 1

• In mixed moderate disease without a clear predominant lesion, individualized decision-making by a multidisciplinary heart team is essential, considering patient symptoms, severity of hemodynamic abnormalities, and surgical risk. 1

Concurrent Cardiac Surgery

If the patient requires other cardiac surgery (CABG, other valve surgery), addressing moderate regurgitation at the time of operation is reasonable, though this remains somewhat controversial for aortic regurgitation per European guidelines. 1

Critical Pitfalls to Avoid

• Do not assume moderate disease is benign—the combination of moderate AR and MR creates additive hemodynamic burden that may cause earlier decompensation than isolated moderate disease. 1

• Avoid relying solely on resting echocardiography in patients with symptoms, as exercise-induced changes in transvalvular flow and hemodynamics may unmask significant pathology. 1

• Do not delay surgical referral once objective markers of left ventricular dysfunction appear (declining EF, increasing dimensions), as outcomes are significantly better when surgery is performed before irreversible ventricular damage occurs. 1

• Recognize that patients may unconsciously reduce activity levels to avoid symptoms—specific questioning about exercise capacity and formal exercise testing are important to detect functional limitations. 3

• Anticoagulation is not indicated for moderate regurgitation in sinus rhythm unless other risk factors exist (atrial fibrillation, history of thromboembolism, significantly enlarged left atrium). 3

• Endocarditis prophylaxis is not routinely recommended for moderate regurgitation unless there is history of prior endocarditis or prosthetic valve. 3