Predictors of cardiac arrest occurring in the context of acute myocardial infarction.

BACKGROUND: Cardiac arrest (CA) concurrent with acute myocardial infarction (AMI) claims the life of many patients with coronary artery disease (CAD). In this study, we investigated the predictors of CA during AMI.

METHOD: Patients admitted with CA concurrent with AMI (n = 31) were matched by age, gender, race, and left ventricular ejection fraction (LVEF) to patients with AMI but no CA (n = 70). All patients underwent coronary angiography. Binary logistic regression was used to identify independent predictors of CA during AMI.

RESULTS: A total of 101 patients (age = 61 +/- 13 years, men 76%, Caucasians 98%, LVEF 33 +/- 12%) admitted to the University of Pittsburgh Medical Center with AMI were included in this analysis. Patients with CA concurrent with the AMI were more likely to have proximal rather than distal coronary artery culprit lesions (odds ratio (OR) = 7.2, P = 0.019). Other predictors of CA in the context of AMI included negative family history of CAD (OR = 8.0, P = 0.026) and absence of sinus rhythm upon hospital admission (OR = 5.1, P = 0.030).

CONCLUSION: Proximity of culprit coronary lesion and presence of rhythm other than sinus rhythm at hospital admission are two strong predictors of CA in the context of AMI. The implication is that the mechanism of CA is primarily that of a large area of myocardial ischemia leading to lethal ventricular arrhythmia. Other predispositions such as genetic make-up cannot be ruled out.