Cardiogenic Shock: A Summary of the Randomized SHOCK Trial

Abstract

Cardiogenic shock is the most common cause of death for patients hospitalized with acute myocardial infarction. The Should We Emergently Revascularize Occluded Coronaries for Cardiogenic Shock (SHOCK) trial randomly assigned 302 patients with predominant left ventricular failure following an acute myocardial infarction to a strategy of emergency revascularization or initial medical stabilization. Emergency revascularization by either coronary artery bypass grafting or angioplasty was required within 6 hours of randomization. Patients assigned to initial medical stabilization could undergo delayed revascularization at a minimum of 54 hours post-randomization. The primary end point of the study was 30-day all-cause mortality. Overall survival at 30 days did not differ significantly between the emergency revascularization and initial medical stabilization groups (53% vs. 44%; p=0.109). However, at the 6- and 12-month follow-up, there was a significant survival benefit with early revascularization (50% vs. 37%; p=0.027 and 47% vs. 34%; p=0.025, respectively). The benefit appeared to be greatest for those less than 75 years of age, with 20 lives saved at 6 months per 100 patients treated. According to the results of the SHOCK trial, the American College of Cardiology/American Heart Association guidelines for myocardial infarction now recommend emergency revascularization for patients younger than 75 years with cardiogenic shock.