Relation between clinical, angiographic and ischemic findings at baseline and ischemia-related adverse outcomes at 1 year in the asymptomatic cardiac ischemia pilot study

Objectives. We attempted to investigate the relation between patient characteristics and adverse outcome in patients with ischemia and clinically stable coronary artery disease (CAD). Background. Evidence suggests that cardiac ischemia, detected by exercise stress testing (ETT) and ambulatory electrocardiographic (AECG) monitoring during daily living, identifies a subgroup of patients at increased risk for adverse outcome, but the relation between these ischemia findings and clinical and angiographic characteristics is largely unknown. Methods. We examined the relation between clinical, angiographic and ischemia characteristics at entry with adverse outcome observed at 1 year in the 558 patients enrolled in the Asymptomatic Cardiac ischemia Pilot (ACIP) study. Results. By the 12-month visit 13.1% of patients had an ischemia-related adverse clinical outcome that included death, nonfatal myocardial infarction or an ischemia-related hospital admission. Multivariate analysis identified only the number of AECG ischemic episodes at entry (odds ratio [OR] 1.06, 99% confidence interval [CI] 1.01 to 1.12, p = 0.002) as an independent predictor of outcome. Assignment to revascularization (as opposed to an initial medical treatment strategy) showed a trend (OR 0.56, 99% CI 0.26 to 1.2, p = 0.05). None of the other baseline clinical, exercise or angiographic variables examined provided additional information relative to adverse outcome. Conclusions. Determinants of adverse outcome, among clinically stable patients with CAD and ischemia induced by stress and daily life were magnitude of AECG ischemia before treatment and, possibly, initial treatment assignment. Among the many other characteristics examined, including age, symptom status and angiographic and exercise variables, none contributed additional independent prognostic information. These two simple variables, which may be modifiable, need further study in a larger trial.