Cardiac power output predicts mortality across a broad spectrum of patients with acute cardiac disease

Abstract

Cardiac power output (CPO) is a novel hemodynamic measurement that represents cardiac pumping ability. The prognostic value of CPO in a broad spectrum of patients with acute cardiac disease undergoing pulmonary artery catheterization (PAC) has not been examined. Consecutive patients with a primary cardiac diagnosis who were undergoing PAC in a single coronary care unit were included. The relationship between initial CPO [(mean arterial pressure x cardiac output [CO])/451] and inhospital mortality was evaluated. CPO was analyzed both as a dichotomous variable (using a cutoff value previously established among patients with cardiogenic shock) and as a continuous variable. Data were available for 349 patients. The mean CPO was 0.88 +/- 0.37 W. The inhospital mortality rate was significantly higher among patients with a CPO < or = 0.53 W (n = 53) compared with those with a CPO > 0.53 W (n = 296) (49% vs 20%, P < .001). In separate multivariate analyses, both CPO and CO were associated with inhospital mortality. However, when both terms were included simultaneously, CPO remained strongly associated with mortality (odds ratio 0.63, 95% CI 0.43-0.91, P = .01), whereas CO did not (odds ratio 1.05, 95% CI 0.75-1.48, P = .78). Cardiac power output is a strong, independent predictor of inhospital mortality in a broad spectrum of patients with primary cardiac disease undergoing PAC.