Background: Although echocardiography is used in diagnosis and management of myocardial infarction, it has not been established whether specific features of cardiac structure or function early in the course of cardiogenic shock provide prognostic value. The purposes of this substudy of the SHould we emergently revascularize Occluded Coronaries for cardiogenic shocK (SHOCK) trial were to describe the echocardiographic features of cardiogenic shock, identify findings on early echocardiograms associated with outcome, examine the interaction of such features with treatment, and determine whether these features could provide insights into the survival benefit observed with early revascularization and guide selection of patients for this strategy.
Methods and results: One hundred seventy-five echocardiograms performed within 24 hours of randomization to the early revascularization (ERV) or initial medical stabilization (IMS) arms of the trial were submitted for quantitative assessment, and 169 were suitable for analysis. The 2 groups were similar in terms of clinical and early echocardiographic characteristics. Mean left ventricular ejection fraction (LVEF) was 31%, and moderate or greater mitral regurgitation (MR) was noted in 39.1%. On multivariate analysis, the only independent predictors of survival were MR severity and LVEF. A survival benefit for the ERV strategy was observed at all levels of LVEF and MR.
Conclusions: A wide range of cardiac structural and functional abnormalities exists in patients presenting with acute cardiogenic shock. Both short- and long-term mortality appear to be associated with initial left ventricular systolic function and MR as assessed by echocardiography, and a benefit of ERV is noted regardless of baseline LVEF or MR.