A Study of Bundle Branch Block as a Prognostic Indicator in Patients of Acute Myocardial Infarction

Abstract

BACKGROUND Acute myocardial infarction (AMI) is an event of myocardial necrosis caused by an unstable ischaemic syndrome, appearance of LBBB or RBBB in patients presenting with myocardial infarction predicts adverse long-term cardiovascular outcomes compared to patients without bundle branch block. MATERIALS AND METHODS This is a case control observational study. We prospectively studied the clinical, laboratorial, electrocardiographical and twodimensional echocardiographic parameters of around 60 patients including 30 patients of myocardial infarction with bundle branch block (Group A) and 30 patients of myocardial infarction without bundle branch block (Group B) at Government Medical College and Hospital, Amritsar. For statistical significance, the "p value" was calculated and a value < 0.05 was considered as significant. RESULTS Mean CPK MB (U/L) in patients of AMI with BBB (Group A) was 255.56 ± 56 and in patients of AMI without BBB (Group B) was 175± 13.59. In Group A 4 (13.33%), 8 (33.33%), 10 (33.33%) and 8 (26.66%) presented in Killip class 1, 2, 3 and 4 respectively. In Group B 10 (33.33%), 12 (40%), 6 (20%) and 2 (6.66%) were in Killip class 1, 2, 3 and 4 respectively. 2D echocardiography revealed that in Group A 21 (70%) patients had regional wall abnormality and 9 (30%) patients in Group B had regional wall motion abnormality. Mortality in Group A was 9 (21%) patients as compared to 2 (6.66%) patients in Group B. CONCLUSION AMI with bundle branch blocks is associated with more in-hospital morbidity and mortality.