Thirteen patients in severe
cardiogenic shock, persisting despite the use of
adrenergic agents, were treated with
enoximone, a recently available
phosphodiesterase inhibitor.
Cardiogenic shock was characterized by
low cardiac output (less than 2.5 liter.min-1.m-2), elevated pulmonary artery balloon-occluded pressure (greater than or equal to 15 mm Hg), decreased urine output (less than 20 ml.hour-1) and increased blood
lactate (greater than or equal to 2.0 mEq.liter-1). Ten patients were mechanically ventilated. A short-term
intravenous infusion of 0.5 mg.kg-1 in 20 minutes of
enoximone resulted in significant increases in cardiac index (from 1.8 +/- 0.3 to 2.9 +/- 0.3 liter.min-1.m-2, p less than 0.001) and
stroke index (from 17.8 +/- 3.3 to 21.9 +/- 5.1 ml.m-2, p less than 0.001) and significant decrease in pulmonary artery balloon-occluded pressure (from 21.7 +/- 5.8 to 19.8 +/- 6.0 mm Hg, p less than 0.01) without a consistent change in mean arterial pressure (from 79 +/- 8 to 76 +/- 9 mm Hg, difference not significant).
Enoximone administration decreased arterial
oxygen tension (from 108 +/- 42 to 94 +/- 36 mm Hg, p less than 0.01) and increased venous admixture (from 12.8 +/- 6.5 to 16.0 +/- 8.0%, p less than 0.01). In 8 patients, a second infusion of 0.5 mg.kg-1 immediately thereafter amplified these changes. All patients but one survived the episode of
cardiogenic shock and 5 patients left the hospital alive. These results indicate that the addition of
enoximone to
adrenergic agents in the treatment of
cardiogenic shock can markedly increase cardiac output and stroke volume without substantial effects on arterial pressure.