COMPARISON OF USEFULNESS OF COMPUTER-ASSISTED CONTINUOUS 48-H 3-LEAD WITH 12-LEAD ECG ISCHEMIA MONITORING FOR DETECTION AND QUANTITATION OFISCHEMIA IN PATIENTS WITH UNSTABLE ANGINA

Aims The selection of ECG leads used for ST monitoring may influence d etection and quantitation of ischaemia. Methods We compared on-line co ntinuous 48-h 12-lead against 3-lead ST monitoring in 130 unstable ang ina patients (Mortara, ELI-100). Onset and offset of ST episodes were defined by the lead with the first greater than or equal to 100 mu V S T change relative to baseline and the lead with the latest return to b aseline ST level, respectively. ST episodes were calculated for 12 lea ds and 3 leads (V-2, V-5, III) separately. Results ST episodes were de tected in 88 patients (77%) by 12-lead and in 71 patients (62%) by 3-l ead ST monitoring (P<0.02). The median number (25, 75%) of episodes/pa tient was 1 (0, 3) for 3-lead and 2 (1, 6) for 12-lead (P<0.0001). The total duration of ischaemia detected during 12-lead far exceeded 3-le ad monitoring: 12.3 (1, 58.2) and 1.7 (0, 23.3) min respectively (P<0. 0001). The probability of recurrent ischaemia declined most during the first 24 h of monitoring. After a period without ST changes of 1, 12, 24 and 36 h, the probabilities of recurrent ischaemia were 63, 31, 14 and 9%, respectively. Conclusions Continuous 12-lead ST monitoring in creases detection rate and duration of ST episodes compared to 3-lead ST monitoring. The use of continuous 12-lead ECG monitoring devices on emergency wards and coronary care units is recommended.