How to treat right ventricular (RV) overload?

Treatment of Right Ventricular Overload

The cornerstone of RV overload management is achieving euvolemia with a target CVP of 8-12 mmHg, not aggressive volume loading, as the traditional approach of preload augmentation worsens RV dilation and ventricular interdependence. 1

Volume Management

Diuresis is the primary intervention for volume-overloaded RV, as it reduces ventricular dilation and improves biventricular coupling by preventing leftward interventricular septal shift that compromises LV filling and cardiac output. 1, 2

• The RV prefers euvolemia, not high preload states despite conventional teaching 1, 2
• RV distention causes interventricular septal shift, compromising LV filling and reducing cardiac output 1
• Target CVP should be maintained at 8-12 mmHg 1, 2

Afterload Reduction

Inhaled selective pulmonary vasodilators are preferred over systemic agents to reduce RV afterload without causing systemic hypotension. 1, 2

• Inhaled nitric oxide (5-10 ppm) reduces pulmonary vascular resistance without systemic hypotension 2
• Inhaled prostacyclin (20-30 ng/kg/min) has comparable efficacy to nitric oxide 2
• Sildenafil (PDE-5 inhibitor) improves exercise capacity and hemodynamics in pulmonary arterial hypertension 2, 3
• Intravenous pulmonary vasodilators can also reduce RV afterload for pulmonary arterial hypertension and RV failure 1

Critical Caveat for Pulmonary Vasodilators

Pulmonary vasodilators may significantly worsen cardiovascular status in patients with pulmonary veno-occlusive disease (PVOD). 3 If signs of pulmonary edema occur when administering sildenafil or other pulmonary vasodilators, consider the possibility of PVOD. 3

Inotropic and Vasopressor Support

Maintain systemic vascular resistance greater than pulmonary vascular resistance (SVR > PVR) to preserve RV coronary perfusion. 2

• Target systolic systemic arterial pressure should be higher than systolic pulmonary arterial pressure 2
• Dobutamine is preferred over milrinone due to shorter half-life when hypotension risk exists 2
• Low-dose norepinephrine is effective and has neutral or beneficial effects on PVR 2
• Vasopressin or norepinephrine may be needed concomitantly with inodilators (particularly milrinone) to maintain RV perfusion by increasing systemic afterload without increasing pulmonary vascular resistance 1

Important Warning About Inotropes

The RV has less contractile reserve than the LV, and calcitropic agents have been associated with progressive decline in RV function, possibly due to systemic vasodilation and decreased right-sided perfusion pressures in the setting of elevated RV pressures. 1

Ventilatory Management (for mechanically ventilated patients)

Optimize PEEP to avoid both lung derecruitment and overdistension, as both worsen RV afterload. 1, 2

• PEEP above 15 cmH₂O promotes overdistension and dramatically worsens RV systolic dysfunction 1, 2
• Sufficient PEEP is required to avoid lung derecruitment and its contribution to RV afterload 1
• Avoid driving pressure ≥18 cmH₂O and PaCO₂ ≥48 mmHg as these are risk factors for RV failure 2
• Vigorous spontaneous breathing efforts should be avoided as forceful inspiratory efforts augment transvascular pressure and can impair RV function 1
• Minimize intrathoracic positive pressure ventilation, correct acidosis, and improve hypoxic pulmonary vasoconstriction 1

Prone Positioning in ARDS

Prone positioning may unload the right ventricle by improving ventilation uniformity and attenuating ventilator-induced lung injury. 1 In two studies, prone positioning actually restored RV function in patients with previously overloaded right ventricles. 1

Advanced Therapies for Refractory Cases

For persistent isolated RV failure refractory to medical therapy, mechanical circulatory support may be indicated. 1, 2

• Venoarterial ECMO is preferred when the primary lesion is the pulmonary vasculature, as RV failure from progressive pulmonary hypertension is poorly treated with devices that only provide RV support (forced perfusion may precipitate pulmonary hemorrhage) 1, 2
• Venovenous ECMO (vvECMO) may help limit pulmonary artery hypertension and unload the right ventricle by increasing blood oxygenation 1
• Impella RP and Protek Duo platforms both bypass the failing RV, with Protek Duo allowing splicing of an oxygenator for concomitant respiratory insufficiency 1

Hemodynamic Monitoring

Invasive hemodynamic assessment with pulmonary artery catheterization is recommended to accurately measure pulmonary vascular resistance, cardiac output, and right atrial pressure. 2

• Echocardiography should assess RV size, function, ventricular interdependence, and tricuspid regurgitation severity 2
• BNP levels predict prognosis 2
• Functional capacity assessment with 6-minute walk test or cardiopulmonary exercise testing is advised 2