title: Silent ischemia during daily life is an independent predictor of mortality in stable angina.
abstract: We prospectively examined the prognostic significance of silent myocardial ischemia detected by ambulatory electrocardiogram (ECG) monitoring during daily life in 107 patients with long-term stable angina who were symptomatically controlled on conventional antianginal agents. Forty-six patients (group 1) demonstrated one or more episodes (87% silent) of myocardial ischemia; the remaining 61 patients (group 2) had no ischemic ST segment changes. During the mean follow-up period of 23 +/- 8 months, 11 cardiac deaths (five sudden and six nonsudden) occurred in group 1, and five cardiac deaths (all nonsudden) occurred in group 2. Kaplan-Meier survival analysis between the groups confirmed that patients with silent ischemia (group 1) had worse prognoses during the follow-up period (p = 0.023). Although the higher incidence of hypertension, smoking, hypercholesterolemia, and diabetes in our patients might reflect a more sickly population of stable angina patients, the multivariate Cox's hazard function analysis of these and other variables including Q waves on ECG, exercise parameters, and ambulatory ECG findings revealed presence of silent ischemia during daily life as the most powerful and independent predictor of cardiac mortality (p = 0.01). These data indicate that, in such patients with stable angina, silent myocardial ischemia occurs frequently during treatment with conventional antianginal drugs and identifies a subset of patients who are at high risk of cardiac death.
authors.affiliation: Department of Medicine, UCSF Program/VAMC 93703.
authors.forename: P C
authors.initials: PC
authors.lastname: Deedwania
authors.forename: E V
authors.initials: EV
authors.lastname: Carbajal
mesh_terms: D000203:Activities of Daily Living; D000787:Angina Pectoris / Q000401:mortality*; D003327:Coronary Disease / Q000453:epidemiology*; D003645:Death, Sudden / Q000453:epidemiology; D015716:Electrocardiography, Ambulatory; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D016019:Survival Analysis