What is the management and treatment plan for a patient with right ventricular dilation, reduced systolic function, and biatrial enlargement?

Management of Right Ventricular Dilation with Reduced Systolic Function and Biatrial Enlargement

This patient requires urgent investigation for the underlying etiology of right ventricular failure, with immediate focus on excluding pulmonary embolism, pulmonary hypertension, and left heart disease, followed by etiology-specific treatment to prevent progression to irreversible right ventricular dysfunction and death.

Immediate Diagnostic Priorities

Exclude Life-Threatening Causes

• Pulmonary embolism must be ruled out emergently with CT pulmonary angiography or ventilation-perfusion scanning, as acute PE causes RV dilation with reduced function and carries 80-100% mortality if untreated 1, 2.
• Look for mobile right heart thrombi on echocardiography, which are associated with large right atrium and atrial fibrillation, and require urgent surgical consultation 2.
• The elevated IVC diameter (25 mm with <50% respiratory collapse) indicates elevated right atrial pressure (~15 mmHg), confirming hemodynamically significant right heart failure 1.

Determine Underlying Etiology

• Assess for left heart disease as the primary driver, as RV dysfunction occurs in 48% of patients with heart failure with reduced ejection fraction and carries a 2.4-fold increased mortality risk 1.
• The preserved LVEF (55%) with mildly increased wall thickness and septal flattening in systole indicates RV pressure overload causing ventricular interdependence—the dilated RV compresses the LV, impairing LV filling despite normal systolic function 1.
• Evaluate for pulmonary hypertension through right heart catheterization to measure pulmonary artery pressures and pulmonary vascular resistance, as the inadequate tricuspid regurgitation jet prevents noninvasive pressure estimation 1.

Critical Diagnostic Studies

• Cardiac MRI is indicated to accurately assess RV volumes, function, and tissue characterization for fibrosis, which helps differentiate cardiomyopathy from other causes 3, 4.
• Obtain ECG to evaluate for right bundle branch block, QRS prolongation >180 ms (marker of increased sudden death risk), and rhythm abnormalities including atrial fibrillation 3.
• 24-hour Holter monitoring is mandatory to detect arrhythmias, as patients with RV dilation and biatrial enlargement are at highest risk for intra-atrial reentrant tachycardia and ventricular arrhythmias 5, 3.

Etiology-Specific Management Framework

If Pulmonary Hypertension is Confirmed

• Declining pulmonary artery pressure in the setting of high pulmonary vascular resistance is an ominous clinical finding indicating decompensated RV failure 1.
• The combination of RV systolic and biventricular diastolic dysfunction reduces cardiac output, impairs coronary blood flow, and exacerbates peripheral and abdominal congestion 1.
• Initiate pulmonary vasodilator therapy based on hemodynamic classification and treat underlying causes (left heart disease, chronic thromboembolic disease, parenchymal lung disease) 1.

If Left Heart Disease is Primary

• Optimize guideline-directed medical therapy for heart failure including ACE inhibitors/ARBs, beta-blockers, mineralocorticoid receptor antagonists, and SGLT2 inhibitors to reduce LV filling pressures 1.
• The biatrial enlargement (LA volume index 41.53 mL/m², RA volume index 50.8 mL/m²) indicates chronic elevation of both left and right-sided filling pressures 1.
• Address volume overload with diuretics, as RV dilation with pericardial constraint impairs LV filling (preload) through ventricular interdependence 1.

If Congenital Heart Disease or Valvular Disease

• The moderately dilated right atrium with physiologic tricuspid regurgitation suggests chronic volume overload that may be congenital or acquired 1.
• Transcatheter or surgical closure is indicated for atrial septal defects causing significant RV enlargement with left-to-right shunt, provided pulmonary artery pressure is less than 50% of systemic pressure 5.
• Tricuspid valve repair should be considered if significant functional tricuspid regurgitation develops secondary to RV dilation and annular dilatation 5.

Arrhythmia Management

Anticoagulation Strategy

• Anticoagulation with warfarin is mandatory given the biatrial enlargement and high risk of thrombus formation, even with only one or two episodes of paroxysmal atrial fibrillation 5.
• The enlarged right atrium creates stasis predisposing to thrombus formation, and warfarin is superior to aspirin for thromboembolism prevention 5.
• Perform transesophageal echocardiography before cardioversion to exclude atrial thrombus 5.

Rhythm Control

• Aggressive strategy for maintaining sinus rhythm is warranted because atrial fibrillation is associated with progressive heart failure, mortality, and stroke in patients with structural heart disease 5.
• Patients with biatrial enlargement or prior atrial surgical incisions are at highest risk for intra-atrial reentrant tachycardia (slow atrial flutter with 2:1 AV conduction) 5, 3.

Sudden Death Risk Stratification

• QRS prolongation >180 ms, particularly if progressive, is a significant risk factor for ventricular tachycardia and sudden cardiac death 3.
• Consider ICD implantation if sustained ventricular arrhythmias develop, unexplained syncope occurs, or progressive QRS prolongation is documented 3.
• Programmed electrical stimulation may help risk-stratify patients with RV dilation and identify those at higher risk for sustained ventricular arrhythmias 3.

Monitoring and Follow-Up

Serial Imaging

• Repeat echocardiography every 3-6 months to monitor RV size and function, as progressive RV dilation and worsening systolic function predict adverse outcomes 1, 5.
• The TAPSE of 22.7 mm (borderline low-normal) indicates early RV systolic dysfunction and requires close monitoring, as TAPSE <16 mm predicts worse outcomes 1.
• Document changes in septal position, as persistent septal flattening indicates ongoing RV pressure overload and ventricular interdependence 1.

Clinical Assessment

• Monitor for signs of decompensation including worsening dyspnea, peripheral edema, ascites, and declining exercise tolerance 1.
• The elevated right atrial pressure (estimated 15 mmHg from IVC parameters) requires aggressive diuresis and close monitoring of renal function 1.

Critical Pitfalls to Avoid

• Do not delay investigation assuming this is isolated RV disease—the majority of RV dysfunction is secondary to left heart disease, pulmonary hypertension, or pulmonary embolism 1.
• Do not rely solely on LVEF to assess cardiac function, as ventricular interdependence means the dilated RV impairs LV filling despite preserved systolic function 1.
• Do not underestimate thromboembolic risk—the combination of biatrial enlargement, elevated right atrial pressure, and potential atrial fibrillation creates extremely high risk for thrombus formation 5, 2.
• Avoid assuming inadequate tricuspid regurgitation signal means normal pulmonary pressures—right heart catheterization is required for definitive assessment 1.