The hypothesis and design of the SHOCK trial have been previously published. Figure 1 outlines the trial design. The trial aimed to test the superiority of a strategy of early committed revascularization (ERV) over that of initial medical stabilization (IMS). Patients assigned to the IMS arm could undergo delayed revascularization at a minimum of 54 hours post-randomization, as per the decision of the local site investigator. For patients to qualify, CS had to occur within 36 hours of the index MI, and randomization had to occur within 12 hours of shock diagnosis. The ERV arm required angioplasty or bypass surgery as soon as possible and within 6 hours of randomization. IABP counterpulsation was strongly recommended for both treatment arms.
Design of the Should We Emergently Revascularize Occluded Coronaries for Cardiogenic Shock (SHOCK) Trial and suggested treatment according to group assignment. Revascularization in the initial medical stabilization arm was at least 48 hours later than in the emergency revascularization arm. PTCA=percutaneous transluminal coronary angioplasty; CABG=coronary artery bypass grafting; IABP=intra-aortic balloon pumping
Standard clinical and hemodynamic criteria were applied for the definition of shock, as outlined in the Table . Only patients with CS arising from predominant left ventricular (LV) failure following MI with ST elevation or new left bundle branch block were included. Exclusion criteria included ventricular septal rupture, cardiac tamponade, severe valvular disease, isolated right ventricular CS, known dilated cardiomyopathy, shock from other causes (e.g., sepsis, hypovolemia), prior severe systemic illness, refusal by the patient's physician, and failure to provide informed consent. All participating sites had institutional review board or ethics committee approval. Patients ineligible for the trial were enrolled in a prospective SHOCK registry.
The primary end point of the study, 30-day all-cause mortality, was monitored by the Data and Safety Monitoring Board. The final sample size of 302 patients had 88%-89% power to detect an absolute 20% mortality difference between the two treatment strategies.
CHF. 2003;9(1) © 2003 Le Jacq Communications, Inc.
Cite this: Cardiogenic Shock: A Summary of the Randomized SHOCK Trial - Medscape - Jan 01, 2003.