Objective: To investigate the efficacy of L-carnitine in patients with right-sided heart failure induced by pulmonary arterial hypertension (PAH).
Methods: A total of 66 pulmonary arterial hypertension patients (14 idiopathic, 36 congenital heart disease associated and 16 connective-tissue disease associated PAH, WHO heart functional class III, n = 38 or IV, n = 28) were enrolled in this study and divided into control group (26 cases) and L-carnitine group (40 cases). All patients received conventional treatment according to guideline for treatment of right-sided heart failure. The patients in L-carnitine group received 5 g/d L-carnitine intravenously for seven days. Six-minute walking distance, WHO heart functional class, physical examination, and serum markers were evaluated at baseline and 7 days after enrollment.
Results: Compared to the baseline, six-minute walking distance was significantly increased (75 m vs. 45 m, P < 0.05), WHO heart functional class significantly improved (improved 2 classes in 16 patients, improved 1 class in 13, no improved in 6, worsen in 5 vs. 3, 8, 9, 6 respectively in the control, P = 0.04), BNP level significant decreased (58.16 ng/L vs. 33.29 ng/L, P = 0.01) and systolic blood pressure significantly increased [8.1 mm Hg vs. 2.4 mm Hg (1 mm Hg = 0.133 kPa), P = 0.03] in L-carnitine group compared with those in control group. No patient was withdrawn from this study for safety reasons.
Conclusions: L-carnitine could improve short-term exercise capacity and WHO heart functional class in right-sided heart failure patients induced by PAH.