Diltiazem reduces pulmonary arterial pressures in recurrent pulmonary hypertension associated with pulmonary hypoplasia

Background/Purpose: Recurrent pulmonary hypertension in the neonatal popula tion is an unusual event with dire consequences. Pulmonary hypertension see n in association with pulmonary hypoplasia may be refractory to conventiona l medical management. The effect of the calcium channel antagonist diltiaze m was studied in five patients with severe pulmonary hypertension. Methods: A retrospective review of the hospital records was performed to de termine the efficacy of diltiazem for refractory pulmonary hypertension. Al l five patients experienced and did not respond to maximal conventional the rapy, which included inhaled nitric oxide, intravenous nitrates, and extrac orporeal membrane oxygenation (ECMO). Right ventricular pressures were dete rmined by transthoracic echocardiograms and were used to document improveme nt in the pressure gradients. Statistical analyses were performed using a p aired Student's t test. A P value of less than .05 was considered significa nt. Results: Diltiazem significantly reduced the right ventricular systolic pre ssure (RVSP) from 82 +/- 8.4 mm Hg to 58.4 +/- 7 mm Hg (P = .008). Two pati ents died; one had a large ventricular septal defect, and the other suffere d multisystem organ failure secondary to sepsis. The surviving patients wer e weaned off diltiazem and did not experience recurrent pulmonary hypertens ion. Conclusions: In cases of pulmonary hypoplasia with recurrent pulmonary hype rtension, diltiazem may be considered as a thera py. A multicenter prospect ive trial is advocated. Copyright (C) 1999 by W.B. Saunders Company.