What is the recommended treatment for a patient with normal left ventricular function, no evidence of myocardial fibrosis or infiltrative disease, and a mildly reduced right ventricular ejection fraction (RVEF) of 37%?

Management of Mildly Reduced Right Ventricular Ejection Fraction with Normal Left Ventricular Function

For patients with normal left ventricular function (LVEF 59%), no evidence of myocardial fibrosis or infiltrative disease, and mildly reduced right ventricular ejection fraction (RVEF 37%), close monitoring with regular follow-up is recommended rather than immediate pharmacological intervention or device therapy.

Understanding the Clinical Significance

The patient's cardiac MRI findings present an interesting clinical scenario:

• Normal left ventricular size, wall thickness, and function (LVEF 59%)
• No evidence of myocardial fibrosis or infiltrative disease
• Mildly reduced right ventricular ejection fraction (RVEF 37%)

Risk Stratification

Right ventricular dysfunction is an important prognostic factor in heart failure. Research has shown that severely reduced RVEF (<20%) is an independent predictor of mortality in heart failure patients 1. However, the patient's RVEF of 37% falls into a less severe category.

Recommended Management Approach

1. Initial Assessment

   • Evaluate for symptoms of right heart failure (exertional dyspnea, fatigue, peripheral edema)
   • Assess for underlying causes of RV dysfunction:
     • Pulmonary hypertension
     • Coronary artery disease
     • Valvular heart disease
     • Congenital heart disease
     • Pulmonary disease

2. Monitoring Strategy

   • Regular clinical follow-up every 3-6 months
   • Serial echocardiography to monitor RV function
   • Consider cardiopulmonary exercise testing to assess functional capacity

3. Pharmacological Therapy

   • In the absence of symptoms and with preserved left ventricular function, there is insufficient evidence to recommend routine use of heart failure medications 2
   • If symptoms develop or RV function deteriorates:
     • Consider beta-blockers, which have shown mortality benefit in patients with right ventricular dysfunction 3, 4
     • SGLT2 inhibitors may be beneficial if the patient develops symptoms, as they have shown a 19% risk reduction in cardiovascular death or heart failure hospitalizations in patients with mildly reduced ejection fraction 3

4. Device Therapy Considerations

   • Current guidelines do not support ICD implantation for primary prevention in patients with:
     • Normal left ventricular function (LVEF >40%)
     • Absence of sustained ventricular arrhythmias
     • No evidence of infiltrative disease 2, 5
   • The 2022 AHA/ACC/HFSA guidelines for heart failure management do not recommend device therapy for isolated right ventricular dysfunction with preserved left ventricular function 2

Special Considerations

Potential Pitfalls to Avoid

1. Overtreatment

   • Avoid unnecessary pharmacotherapy in asymptomatic patients with mildly reduced RVEF and normal LV function
   • The risk-benefit ratio of heart failure medications may not favor treatment in this scenario

2. Underdiagnosis of Progressive Disease

   • Monitor for signs of disease progression, as some patients with initially preserved LVEF may develop reduced LVEF over time 6
   • Patients with LVEF ≤55% and ischemic etiology are at higher risk for progression to heart failure with mildly reduced ejection fraction 6

3. Overlooking Pulmonary Hypertension

   • Right ventricular dysfunction may be an early sign of pulmonary hypertension
   • Consider evaluation for pulmonary hypertension if clinically suspected 7

When to Consider More Aggressive Management

• Development of symptoms (NYHA class II-IV)
• Further decline in RVEF (<30%)
• Development of ventricular arrhythmias
• Evidence of progressive right ventricular remodeling

Conclusion

In the absence of symptoms and with normal left ventricular function, a patient with mildly reduced RVEF (37%) should be monitored closely rather than immediately treated with heart failure medications or device therapy. This approach balances the risk of disease progression against the potential side effects and costs of unnecessary treatment.