What is the best course of treatment for a patient with an ejection fraction (EF) of 50-55%, left ventricular (LV) enlargement, and moderate regurgitation on echocardiogram?

Management of Ejection Fraction 50-55% with Left Ventricular Enlargement and Moderate Regurgitation

You need urgent cardiology referral and likely surgical evaluation, as this presentation represents borderline systolic dysfunction with significant structural changes that predict adverse outcomes and may warrant intervention even before symptoms develop.

Critical Context: EF 50-55% is NOT Normal in Valvular Disease

• An ejection fraction of 50-55% represents early left ventricular dysfunction in the setting of chronic regurgitation, not "preserved" function 1, 2
• Guidelines define LV systolic dysfunction as LVEF <60% in aortic regurgitation and LVEF ≤60% in mitral regurgitation when considering surgical intervention 1
• This "low-normal" EF range (50-55%) is associated with 3.6-fold increased risk of heart failure progression even in asymptomatic patients 3
• In valvular regurgitation, the ventricle ejects into a low-resistance chamber, artificially inflating the EF measurement—thus an EF of 50-55% indicates more severe dysfunction than it would in other conditions 4, 2

Immediate Diagnostic Clarification Required

You must first determine which valve has moderate regurgitation, as management differs substantially:

If Moderate-to-Severe Mitral Regurgitation:

• Surgery is indicated (Class I recommendation) for asymptomatic patients with chronic severe primary MR when LVEF is 30-60% and/or LV end-systolic dimension ≥40 mm 1
• Your patient's EF of 50-55% falls squarely in this range indicating LV dysfunction 1
• Mitral valve repair is strongly preferred over replacement when feasible 1
• Do not wait for further EF decline—outcomes worsen significantly once LVEF drops below 60% in MR 1

If Moderate-to-Severe Aortic Regurgitation:

• Surgery should be considered (Class IIa) for asymptomatic patients with severe AR when LVEF is ≤50% OR LV end-systolic dimension ≥50 mm (or ≥25 mm/m² BSA) OR LV end-diastolic dimension >70 mm 1
• Your patient's EF of 50-55% with LV enlargement meets criteria for surgical consideration 1
• LVEF deterioration accelerates once aortic valve area reaches critical stenosis, and decline often begins before regurgitation becomes severe 2

Essential Additional Echocardiographic Parameters Needed

Request these specific measurements immediately (if not already documented):

• LV end-systolic dimension (LVESD): Surgery indicated if ≥40 mm in MR or ≥50 mm in AR 1
• LV end-diastolic dimension (LVEDD): Surgery considered if >70 mm in AR 1
• Indexed measurements: LVESD >25 mm/m² BSA is significant 1
• Severity quantification: Confirm "moderate" regurgitation with vena contracta, regurgitant volume, effective regurgitant orifice area 1
• Global longitudinal strain (GLS): Values worse than -16% to -18% indicate subclinical dysfunction even with preserved EF 1, 5
• Tissue Doppler velocities: Reduced E' velocity (<8 cm/s septal, <10 cm/s lateral) indicates diastolic dysfunction 5
• E/E' ratio: Values >15 suggest elevated filling pressures 5
• Left atrial volume index: ≥34 mL/m² indicates chronic volume overload 5

Medical Management While Awaiting Surgical Evaluation

For Aortic Regurgitation:

• ACE inhibitors or ARBs are indicated if hypertension is present 1
• Vasodilators may improve hemodynamics in symptomatic patients with severe heart failure before surgery 1
• Beta-blockers are NOT routinely indicated for AR unless there is Marfan syndrome with aortic root dilatation 1
• Evidence does NOT support vasodilators in asymptomatic normotensive patients to delay surgery 1

For Mitral Regurgitation:

• Medical therapy for systolic dysfunction (ACE inhibitors/ARBs, beta-blockers) is reasonable in symptomatic patients with LVEF <60% when surgery is not immediately performed 1
• However, medical therapy is NOT a substitute for timely surgical intervention in appropriate candidates 1

Monitoring Strategy if Surgery Deferred

If surgical intervention is delayed (which should be carefully justified):

• Repeat echocardiography every 6 months to monitor for progression 1
• Clinical evaluation every 6 months for symptom development 1
• Immediate re-evaluation if ANY symptoms develop (dyspnea, decreased exercise tolerance, orthopnea, edema) 1, 5
• Monitor for new-onset atrial fibrillation, which may prompt earlier intervention 1

Red Flags Requiring Urgent Surgical Referral

Any of the following mandate immediate surgical evaluation:

• Development of ANY symptoms attributable to heart failure 1
• Further decline in LVEF on serial imaging 1
• Progressive LV dilatation (increase in LVESD or LVEDD) 1
• New-onset atrial fibrillation 1
• Pulmonary hypertension on echocardiography 1

Common Pitfalls to Avoid

• Do not reassure the patient that EF 50-55% is "normal"—it represents dysfunction in the context of chronic regurgitation 1, 4, 2
• Do not wait for symptoms to develop—outcomes are significantly worse when surgery is delayed until symptomatic 1
• Do not rely solely on EF—incorporate LV dimensions, indexed measurements, and strain imaging 1, 4
• Do not assume medical therapy can substitute for surgery in patients meeting surgical criteria 1
• Do not normalize LV dimensions for body surface area in overweight patients, as this masks true LV enlargement 1

Prognosis Without Intervention

• Patients with "low-normal" EF (50-55%) have 3.6-fold increased risk of developing heart failure over 10 years 3
• Mortality risk increases progressively as LVEF declines from 60% to 50%, even in asymptomatic patients 3, 6
• 11% of patients with HFpEF and EF ≤55% progress to heart failure with mildly reduced EF within 2-3 years 6
• Postoperative LV function recovery is significantly better when surgery is performed before LVEF falls below 60% 1, 2