What is the management approach for a patient with moderate to severe aortic regurgitation?

Management of Moderate to Severe Aortic Regurgitation

Symptomatic Severe AR: Immediate Surgical Intervention

Surgery is indicated for all patients with symptomatic severe aortic regurgitation regardless of left ventricular ejection fraction or surgical risk (Class I recommendation). 1

• Symptoms include dyspnea, angina, heart failure, or reduced exercise tolerance 1
• Aortic valve replacement (AVR) should not be delayed once symptoms develop, as mortality risk increases substantially (24.6% yearly in symptomatic patients managed conservatively) 2
• Both mechanical and bioprosthetic valve replacement are acceptable options 1
• At experienced centers, valve-sparing aortic root surgery may be considered in anatomically suitable patients with bicuspid aortic valve 1

Asymptomatic Severe AR: LV Function and Size Thresholds

Surgery is indicated in asymptomatic patients when left ventricular systolic dysfunction develops or when specific LV dimensional criteria are met. 1

LVEF-Based Criteria:

• ACC/AHA threshold: LVEF ≤55% (when no other cause explains the dysfunction) 1
• JCS threshold: LVEF <50% 1
• ESC threshold: LVEF ≤50% at rest 1
• Asymptomatic patients with LVEF <55% have excess mortality (5.8% yearly) without surgery 2

LV Dimensional Criteria:

• Left ventricular end-systolic diameter (LVESD) >50 mm (Class IIa) 1
• LVESD indexed to body surface area >25 mm/m² (associated with 7.8% yearly mortality if untreated) 1, 2
• LVESD >45 mm is reasonable per JCS guidelines 1
• LV end-diastolic diameter (LVEDD) >65 mm may be considered as a trigger 1

Progressive LV Changes:

• Surgery may be considered with progressive decline in LVEF on at least three serial studies 1
• Progressive LV dilatation into the severe range warrants intervention 1

Moderate AR: Surveillance and Medical Management

Moderate aortic regurgitation does not require surgery unless concurrent cardiac surgery is being performed for other indications. 3

Surveillance Protocol:

• Echocardiographic follow-up every 1-2 years to detect progression 1, 3
• Yearly clinical assessment for symptom development 3
• More frequent imaging (every 3-6 months) if LVEF declines or progressive LV dilatation occurs 1, 3

Medical Therapy:

• Blood pressure control is essential for hypertensive patients (systolic BP >140 mmHg) 1, 3
• Preferred agents: ACE inhibitors or dihydropyridine calcium channel blockers (e.g., nifedipine, amlodipine) 1, 3, 4
• These vasodilators reduce LV afterload without slowing heart rate 3
• Avoid beta-blockers as they prolong diastole and increase regurgitant volume 3

Surgical Consideration for Moderate AR:

• AVR is reasonable (Class IIa) when patients undergo CABG, mitral valve surgery, or ascending aorta surgery 1, 3

Acute Severe AR: Emergency Management

Acute severe aortic regurgitation is a surgical emergency requiring immediate intervention. 1

• Medical therapy to reduce LV afterload may temporarily stabilize patients but surgery should not be delayed, especially with hypotension, pulmonary edema, or low cardiac output 1
• Intra-aortic balloon counterpulsation is contraindicated 1
• CT imaging is the primary diagnostic approach for aortic dissection 1
• TEE has 98-100% sensitivity for Type A aortic dissection 1

Aortic Root Considerations

When severe AR requires surgery and the aortic root is dilated, concomitant aortic root replacement should be performed. 1

• Replacement of aortic sinuses and/or ascending aorta is reasonable when aortic dimension is ≥45 mm at a comprehensive valve center 1
• Valve-sparing surgery may be considered in bicuspid aortic valve patients at experienced centers 1

High-Risk and Prohibitive-Risk Patients

For patients with prohibitive surgical risk, guideline-directed medical therapy (GDMT) for reduced LVEF is recommended. 1

• Use ACE inhibitors, ARBs, and/or sacubitril/valsartan 1
• TAVI should not be performed in patients with isolated severe AR who are surgical candidates 1
• TAVI may be considered at experienced centers for selected patients ineligible for SAVR 1

Critical Pitfalls to Avoid

• Do not wait for symptoms to develop in patients with LVEF ≤55% or LVESD >50 mm - these patients already have excess mortality 2
• Do not rely on a single echocardiographic measurement - confirm LV dysfunction or dilatation on serial studies before recommending surgery 5
• Do not use beta-blockers for blood pressure control in chronic AR (except in aortic dissection) 3
• Do not delay surgery in symptomatic patients even with preserved LVEF - mortality increases dramatically 2
• Patients with even mild (Class II) symptoms have 6.3% yearly mortality without surgery 2