Iturrate, Eduardo
Sponsor: Judith, Hochman
The leading cause of death in patients hospitalized for acute myocardial infarction is cardiogenic shock. We conducted a randomized trial to evaluate early revascularization in patients with cardiogenic shock. In patients with cardiogenic shock, emergency revascularization did not significantly reduce overall mortality at 30 days. However, after six months there was a significant survival benefit. Our conclusion was that early revascularization should be strongly considered for patients with acute myocardial infarction complicated by cardiogenic shock. We are making original data that was collected for this trial available here for further analysis.
Although the SHOCK trial[1] was completed decades ago, it is a unique and valuable dataset. There was a publication[2] using these data a few years ago and a recent proposal using these data was sent to the principal investigators of the original study. Other analyses have been reported well after the NHLBI grant-funded project ended [7, 8, 9]
Cardiogenic shock complicates 7 to 10 percent of cases of acute myocardial infarction and is associated with a 70 to 80 percent mortality rate[3]. Cardiogenic shock remains the leading cause of death in patients hospitalized with myocardial infarction in the reperfusion era[4]. Nonrandomized studies report markedly lower mortality rates among patients who have undergone re-vascularization for shock. However, selection bias is evident. In small series of patients undergoing early primary angioplasty for cardiogenic shock, in-hospital mortality rates ranged from 26 percent to 72 percent[5]. A prematurely terminated randomized trial comparing angioplasty with conventional therapy for shock in 55 patients reported no difference in mortality.
Prior to this trial and the new national guideline recommendations, most patients with cardiogenic shock did not undergo emergency revascularization, either because of the lack of facilities at the hospitals where they present or because of doubt as to its efficacy. Early revascularization (angioplasty or coronary-artery bypass graft surgery) is now a Class I recommendation: it reduces mortality, and should be performed on an urgent basis, even if this requires transfer to a hospital with the necessary facilities and expertise. Community studies show that use has increased and is associated with concomitant reduction in mortality.
Patients with shock due to left ventricular failure complicating myocardial infarction were randomly assigned to emergency revascularization (152 patients) or initial medical stabilization (150 patients). Revascularization was accomplished by either coronary-artery bypass grafting or angioplasty. Intraaortic balloon counterpulsation was performed in 86 percent of the patients in both groups. The primary end point was mortality from all causes at 30 days. Six-month survival was a secondary end point. Screened patients with suspected cardiogenic shock due to AMI that were ineligible or did not consent were entered in a registry. The SHOCK Trial demonstrated that emergency revascularization reduced all-cause mortality by 13% absolute percentage at 6 months, which was durable in long-term follow-up [1, 10]
Data were entered by participating sites into a structured database housed at NERI (now HealthCore).
The dataset made available here has been deidentified using the 'safe harbor' approach. All patient identifiers were removed, all dates were rolled up to only indicate the year. A unique ID number was created for each patient for the purposes of linking patients between files. There are no patients in the dataset with age >90.