Sublingual nifedipine: acute effects in severe chronic congestive heart failure secondary to idiopathic dilated cardiomyopathy.

Nine patients with chronic, severe (New York Heart Association class III to IV) congestive heart failure were studied to determine the acute effects of 10 mg of sublingual nifedipine on left ventricular (LV) function. Hemodynamic and echocardiographic data were obtained at rest and 30 minutes, 1, 2, 4 and 6 hours after nifedipine. Measurements at rest reflected LV dysfunction with elevation of end-diastolic volume index (102 +/- 46 ml/m2), pulmonary capillary wedge pressure (17 +/- 8 mm Hg), systemic vascular resistance (1,547 +/- 439 dynes s cm-5) and reduction of cardiac index (2.8 +/- 0.5 liters/min/m2). There were no adverse effects noted with administration of sublingual nifedipine. Initial changes through 1 hour reflected an unloading effect of nifedipine with reduction in pulmonary capillary wedge pressure (11 +/- 5 mm Hg) (p less than 0.05), systemic vascular resistance (1,179 +/- 289 dynes s cm-5) (p less than 0.01), end-diastolic volume index (91 +/- 37 ml/m2 [difference not significant]) and an increase in cardiac index (3.6 +/- 0.7 ml liters/min/m2) (p less than 0.01). Subsequently the cardiac index, systemic vascular resistance and end-diastolic volume index returned toward baseline. Only the pulmonary capillary wedge and pulmonary artery pressures demonstrated a sustained reduction through the 6-hour study period suggesting an effect of nifedipine on LV relaxation. Thus, sublingual nifedipine administered acutely to patients with clinical congestive heart failure is a safe and efficacious vasodilator.