Percutaneous coronary intervention for cardiac arrest secondary to ST-elevation acute myocardial infarction. Influence of immediate paramedical/medical assistance on clinical outcome.

BACKGROUND: Patients with cardiac arrest have been excluded from most randomized trials on percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI).

OBJECTIVE: The aim of the study was to evaluate the outcome of patients undergoing primary PCI for acute myocardial infarction who suffered from cardiac arrest prior to the procedure, focusing the study on the influence of immediate paramedical-medical assistance on the outcome.

METHODS AND RESULTS: Sixty-three patients with ST-elevation AMI and previous cardiac arrest underwent primary PCI within 12 hours after symptom onset. Three groups of patients were defined: Group 1: Cardiac arrest before hospital admission, without immediate (< 1 minute) initiation of resuscitation maneuvers (n = 13); Group 2: Pre-hospital cardiac arrest with immediate initiation of resuscitation maneuvers (n = 14); Group 3: Cardiac arrest after hospital admission. The proportion of patients with ventricular tachycardia or fibrillation as documented initial rhythm was similar among the groups (77%, 79% and 83%, respectively), as well as the rate of angiographic success (92%, 93% and 86%, respectively). However, the incidence of cardiac events at 30 days was significantly higher in Group 1 than in Groups 2 or 3 (54%, 29% and 17%, respectively; p = 0.03), as well as the mortality rate at 30 days (46%, 21% and 18%, respectively; p = 0.06). Interestingly, the outcomes were not statistically different between Groups 2 and 3. In multivariate analysis, the independent predictors for mortality at 30 days for Group 1 were: multivessel disease, angiographic failure and cardiogenic shock.

CONCLUSIONS: Combining immediate initiation of resuscitation maneuvers and primary PCI yields a very good clinical outcome in patients with AMI suffering from cardiac arrest.