Abstract 10949: Left Bundle Branch Block in Suspected Acute Myocardial Infarction
INTRODUCTION: According to guidelines, patients presenting with chest pain and ST elevation (STE) or (presumed) new LBBB should undergo a primary angioplasty. Our objective was to evaluate the clinical differences and outcome between patients presenting with LBBB and those with ST elevation.
METHODS: Prospective study of all consecutive patients included in a regional network of primary angioplasty (Codi IAM, Catalunya, Spain) during 2010-2011. Two groups were established for comparison: STE group and LBBB group.
RESULTS: The study population included 4593 patients, of which 4470 (97.3%) had STE and 123 patients (2.7%) had LBBB. Patients with LBBB were older (68.4±11.6 vs 62.6±13.7, p<0.001), more frequently women (37% vs 22%, p<0.001), had higher proportion of diabetes (37% vs 20%, p<0.001), previous history of AMI (18 vs 11%, p=0.029) and previous angioplasty (15 vs 7%, p=0.009). Median time since the start of chest pain to first medical contact (74 [35-170] min) and from therapeutic decision (revascularization) to angioplasty (78 [60-105] min) was similar between both groups. However, time from ECG to therapeutic decision was higher in the LBBB group (median 36 [16-65] min vs 24 [11-47] min, p=0.0002). A primary angioplasty was performed more frequently in the STE group (85% vs 36% in patients with LBBB, p<0.0001). Cardiogenic shock was more frequent in LBBB patients (16% vs 6%, p<0.0001). In-hospital mortality was higher in patients with LBBB as compared with STE group (5.7 % (7/123 patients) vs 2.4% (105/4470), p=0.03). Nonetheless, 30 days mortality was similar between groups (5.7% in group B vs 4.2% in group A, p=0.363).
CONCLUSIONS: Only one third of patients with LBBB who underwent an angiogram in the setting of chest pain had a thrombotic coronary artery occlusion amenable of treatment with angioplasty. However, in-hospital mortality in this group of patients was high.
- © 2013 by American Heart Association, Inc.