title: Noninvasive assessment of reperfusion after fibrinolytic therapy for acute myocardial infarction.
abstract: Assessment of reperfusion by the 12-lead electrocardiogram (ECG) or biochemical markers is limited by suboptimal sensitivity and/or specificity. Body surface mapping (BSM) improves the spatial sampling of the 12-lead ECG. Serial 12-lead ECGs and 64-lead anterior BSMs were recorded from 67 patients with acute myocardial infarction undergoing coronary angiography 90 minutes after fibrinolytic therapy. ECG-1 and BSM-1 were recorded before/shortly after therapy (median 18 minutes). ECG-2 and BSM-2 were recorded after the 90-minute angiogram (median 30 minutes). The maximum ST elevation on ECG-1 was noted and > or = 30% ST resolution on ECG-2 was taken to represent partial/complete reperfusion. Patients were randomly divided into a training set and validation set. Isointegral and isopotential ST-T variables from BSMs of training-set patients were compared with Thrombolysis In Myocardial Infarction (TIMI) trial flow using discriminant analysis to identify which variables best classified reperfusion. Reperfusion (TIMI 2/3 flow) occurred in 32 of 34 training-set patients and in 29 of 33 validation-set patients. In the training set, > or = 30% ST resolution correctly classified reperfusion with 72% sensitivity (23 of 32) and 50% specificity (1 of 2). In the validation set, > or = 30% ST resolution classified reperfusion with 59% sensitivity (17 of 29) and 50% specificity (2 of 4). In comparison, a model containing 24 BSM variables correctly classified all training-set patients, and when prospectively tested in the validation-set, correctly classified 28 of 29 patients who achieved reperfusion (97% sensitivity) and all 4 patients who failed to reperfuse (p = 0.035). In conclusion, BSM is more useful than the 12-lead ECG for noninvasive assessment of reperfusion after fibrinolytic therapy for acute myocardial infarction.
authors.affiliation: Regional Medical Cardiology Center, Royal Victoria Hospital, Belfast, Northern Ireland, United Kingdom.
authors.forename: I B
authors.initials: IB
authors.lastname: Menown
authors.forename: J
authors.initials: J
authors.lastname: Allen
authors.forename: J M
authors.initials: JM
authors.lastname: Anderson
authors.forename: A A
authors.initials: AA
authors.lastname: Adgey
mesh_terms: D000704:Analysis of Variance; D015415:Biomarkers / Q000097:blood; D018780:Body Surface Potential Mapping / Q000379:methods*; D003326:Coronary Circulation / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000188:drug therapy* / Q000503:physiopathology*; D011446:Prospective Studies; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers