Cardiac power is the strongest hemodynamic correlate of mortality in cardiogenic shock: a report from the SHOCK trial registry.

OBJECTIVES: We sought to analyze clinical, angiographic, and outcome correlates of hemodynamic parameters in cardiogenic shock.
BACKGROUND: The significance of right heart catheterization in critically ill patients is controversial, despite the prognostic importance of the derived measurements. Cardiac power is a novel hemodynamic parameter.
METHODS: A total of 541 patients with cardiogenic shock who were enrolled in the SHould we emergently revascularize Occluded Coronaries for cardiogenic shocK (SHOCK) trial registry were included. Cardiac power output (CPO) (W) was calculated as mean arterial pressure x cardiac output/451.
RESULTS: On univariate analysis, CPO, cardiac power index (CPI), cardiac output, cardiac index, stroke volume, left ventricular work, left ventricular work index, stroke work, mean arterial pressure, systolic and diastolic blood pressure (all p < 0.001), coronary perfusion pressure (p = 0.002), ejection fraction (p = 0.013), and pulmonary artery systolic pressure (p = 0.047) were associated with in-hospital mortality. In separate multivariate analyses, CPO (odds ratio per 0.20 W: 0.60 [95% confidence interval, 0.44 to 0.83], p = 0.002; n = 181) and CPI (odds ratio per 0.10 W/m(2): 0.65 [95% confidence interval, 0.48 to 0.87], p = 0.004; n = 178) remained the strongest independent hemodynamic correlates of in-hospital mortality after adjusting for age and history of hypertension. There was an inverse correlation between CPI and age (correlation coefficient: -0.334, p < 0.001). Women had a lower CPI than men (0.29 +/- 0.11 vs. 0.35 +/- 0.15 W/m(2), p = 0.005). After adjusting for age, female gender remained associated with CPI (p = 0.032).
CONCLUSIONS: Cardiac power is the strongest independent hemodynamic correlate of in-hospital mortality in patients with cardiogenic shock. Increasing age and female gender are independently associated with lower cardiac power.