|Variable||Hazard Ratio||95% Confidence Interval||p Value|
|Diastolic blood pressure ≥80 mm Hg||1.61||1.03–2.52||0.04|
|Interim appropriate shock||2.25||1.09–4.67||0.03|
Other covariates tested but not found significant in multivariate analysis included absence of beta-blocker therapy, prior coronary artery bypass graft procedure, blood urea nitrogen >25, and interim hospitalization for either congestive heart failure, myocardial infarction, or unstable angina. An alternative analysis that also included interim atrial fibrillation found this to be a highly significant predictor of inappropriate shock (hazard ratio 3.45, 95% confidence interval 1.55 to 7.69, p < 0.01); the other variables remained significant.