Prediction of coronary artery disease and cardiac events using electrocardiographic changes during hemodialysis

Hemodialysis(HD) patients have a high rate of cardiac morbidity and mortali ty. Both symptomatic and silent ischemic heart disease may occur frequently during HD because HD simultaneously reduces coronary artery oxygen deliver y while increasing myocardial oxygen demand. The purpose of the present stu dy Is to prospectively evaluate the usefulness of a significant ST depressi on induced by HD for the diagnosis of coronary artery disease (CAD) and as the predictor of subsequent cardiac events in HD patients. Sixty-one patien ts undergoing chronic HD (50 men, 11 women; mean age, 61 years) admitted fo r such cardiac symptoms as chest pain (n = 43), arrhythmia (n = 5), or hear t failure (n = 13) were studied; 38 patients had CAD by coronary angiograph y. Electrocardiograms performed during HD showed an additional depression ( greater than or equal to 1.0 mV) of the ST segment in 18 patients (positive -ST group), but not in 43 patients (negative-ST group). The incidence of CA D was significantly greater in the former (100%) than in the latter group ( 46%). A prospective follow-up was performed for 21 +/- 2 months, and cardia c events occurred in all positive-ST group patients and in 21 negative-ST g roup patients. Event-free survival was poorer in the positive-ST group (P < 0.0001). A Cox proportional hazards model identified the significant ST de pression as an independent risk factor for cardiac morbidity (P < 0.05), bu t not for ail-cause mortality. ST depression during HD is useful to diagnos e CAD in symptomatic patients and is considered an important prognosticator of subsequent cardiac events. (C) 2000 by the National Kidney Foundation, Inc.