A study of clinical profile and etiology of left bundle branch block

Background: Left bundle branch block (LBBB) is a quite common disorder associated with a three to four fold increase in cumulative cardiovascular mortality. Although risk is especially increased for LBBB when accompanied an organic heart disease, it has been reported that mortality is also high in isolated LBBB. Objective: To study clinical profile and etiology of left bundle branch block Methods: The present cross sectional analytical study was carried out among 100 cases of left bundle branch block attending the outpatient department. All cases fulfilling ECG criteria of LBBB were included in the present study. The various criteria for LBBB were QRS duration > 120 msec, broad, notched R waves in lateral precordial leads (V5 and V6) and usually leads I and AVL, Small or absent r waves in right precordial leads (V1 and V2) followed by deep S waves, Absent septal q waves in left sided leads and prolonged intrinsicoid deflection (> 60 msec) in V5 and V6. Results: Mean age in low LVEF group was 56.6+9.92 years and in the normal LVEF group it was 53.27+10.71 years. Males predominated in both the groups. In cases of LBBB with valvular heart disease there was no significant difference between two groups of LVEF Conclusion: Hypertension and ischemic heart disease contributed to maximum cases of LBBB. Patient of LBBB with coronary artery disease and dilated cardiomyopathy have low LVEF while the patients of idiopathic LBBB had normal ejection fraction