Pulmonary Vasodilator Therapy in Patients With Fontan Circulation: A Meta-Analysis

The effect of pulmonary vasodilator therapy on patients with Fontan circulation remains unclear. This study aims to assess its impact on exercise capacity and hemodynamic parameters in this population.

We searched PubMed, Embase, and the Cochrane Library for relevant studies up to November 2023. Pooled outcomes were used to evaluate the efficacy of pulmonary vasodilators in Fontan patients.

A total of 18 studies with 667 patients were included. Exercise capacity was assessed in 14 studies (526 patients). Pulmonary vasodilator therapy improved oxygen consumption anaerobic threshold (VO₂AT; MD, 1.12 mL/min/kg; 95% CI, 0.35 to 1.89; p=0.004) and Ve/VCO₂ slope (MD, -1.14; 95% CI, -1.97 to -0.31; p=0.007) during exercise. No significant differences were found among drug classes regarding peak oxygen consumption, Ve/VCO₂, or VO₂AT. Invasive hemodynamics were evaluated in 6 studies (126 patients). Pulmonary vasodilators significantly reduced mean pulmonary arterial pressure (MD, -2.28 mmHg; p=0.02), pulmonary vascular resistance (MD, -0.91 WU*m²; p=0.01), and improved pulmonary flow (MD, 0.46 L/min/m²; p=0.02).

Pulmonary vasodilator therapy appears beneficial for exercise capacity and pulmonary hemodynamics in Fontan patients. More randomized controlled trials are needed to confirm these findings.