Continuous 12-lead electrocardiographic ST monitoring and long-term prognosis after successful coronary stenting

Background The possible long-term prognostic value of transient ST ischemic episodes detected by continuous multilead electrocardiographic (ECG) monitoring after successful coronary stenting (CS) has not been thoroughly investigated. Methods A total of 739 consecutive patients, who underwent a 24-hour, continuous 12-lead electrocardiographic (ECG) ST monitoring in the first day after successful CS, were studied. An ST ischemic episode was defined as a transient ST shift (depression or elevation) in any lead of ≥0.10 mV compared with the reference ECG lasting for ≥1 minute. Results The incidence of the composite of death, nonfatal myocardial infarction, and recurrent angina by the first year was 28.7%. Patients with ≥3 (defined by receiver operating characteristics analysis) ST ischemic episodes, detected by continuous 12-lead ECG ST monitoring, were at significantly higher risk for the 1-year composite primary end point than those with either 1 and 2 (52.7% vs 25.7%, hazard ratio [HR] 2.1, 95% CI 1.4-3.7, P < .001) or no (52.7% vs 25%, HR 2.2, 95% CI 1.2-2.9, P < .001) ST ischemic episodes. By multivariate Cox regression analysis, the occurrence of ≥3 ST ischemic episodes in the first postprocedural day was independently associated with a significant increased risk of the 1-year composite primary end point (HR 1.9, 95% CI 1.4-3.9, P = .002). Conclusions The present study suggests that continuous 12-lead ECG ST monitoring in the first day after successful CS may serve as an affordable tool for the identification of patients with an increased risk of fatal or nonfatal ischemic complication during the first year after the procedure.