Hemodynamic Assessment of Amrinone

TLDR

Amrinone, a new bipyridine derivative with positive inotropic effects in experimental preparations and oral efficacy in dogs, remains mechanistically undefined but is a promising heart‑failure treatment. The study aimed to evaluate the immediate hemodynamic effects of intravenous amrinone in patients with congestive heart failure on full‑dose digitalis. Using cardiac catheterization, eight such patients received 1.85–3.5 mg/kg intravenous amrinone and their hemodynamic responses were recorded. Amrinone significantly increased cardiac index from 1.8 to 2.6 L/min/m², raised peak LV pressure rise from 849 to 1206 mm Hg/s, lowered LV end‑diastolic pressure from 25 to 14 mm Hg, reduced pulmonary capillary pressure from 28 to 15 mm Hg, and decreased right atrial pressure from 12 to 7 mm Hg; heart rate remained unchanged, aortic mean pressure fell slightly, and no toxicity was observed. Published in N Engl J Med 1978 (vol.

Abstract

Amrinone, a new bipyridine derivative, exerts a positive inotropic action in experimental preparations and is effective when administered orally to dogs. To assess its immediate effects in man, we studied by cardiac catheterization the hemodynamic responses to amrinone (1.85 to 3.5 mg per kilogram given intravenously) in eight patients with congestive heart failure already receiving full doses of digitalis. The following statistically significant (P<0.01) effects were noted: cardiac index increased from a mean±1 S.D. of 1.8±0.3 to 2.6±0.3 liters per minute per square meter; peak rate of left ventricular pressure rise rose from 849±233 to 1206±456 mm Hg per second; left ventricular end-diastolic pressure fell from 25±9 to 14±7 mm Hg; pulmonary-capillary pressure fell from 28±8 to 15±4 mm Hg; and right atrial pressure fell from 12±6 to 7±5 mm Hg. Mean heart rate was unchanged, and aortic mean pressure declined slightly (86±10 to 80±7 mm Hg, P<0.025). No toxicity was observed. Amrinone, whose mechanism of action has not yet been defined, warrants further study as a possible treatment for heart failure. (N Engl J Med 299:1373–1377, 1978)