OBJECTIVE To compare the different effects of right ventricular pacing and classic left bundle branch block on left ventricular function. DESIGN Retrospective and prospective study of 48 patients by electrocardiography, and M mode, cross sectional, and Doppler echocardiography. SETTING A tertiary cardiac referral centre. PATIENTS 48 patients (age range 21 to 89 years, 15 women), 24 with a...

Reentry within the His-Purkinje System (V3 phenomenon) where the reentry pathway incorporates both bundle branches and the bundle of His is a frequent phenomenon during ventricular refractory period studies. In this form of reentry, both divisions of the left bundle branch function as a single limb and the reentrant beats (V3) have either left bundle branch block or right bundle branch block pa...

A 55-year-old woman with dilated cardiomyopathy and rate-dependent left bundle branch block had a cardiac resynchronisation therapy (CRT) device implanted. During implantation, the maximum rate of left ventricular pressure rise (dP/dt(max)) was measured invasively. This case presents a description of the acute negative effect of a left bundle branch block on dP/dt(max), and the different effect...

To validate the accuracy of catheter endocardial mapping to localize the origin of ventricular tachycardia (VT), we compared cathether endocardial mapping with intraoperative epicardial and endocardial mapping of 24 morphologically distinct VTs in 18 patients undergoing surgery. Twelve had VT with left bundle branch block morphology and 12 had VT with right bundle branch block morphology. Cathe...

A twenty year follow up of a selected, community population with complete right and left bundle branch block is reviewed by comparative mortality analysis. In this population, where cases and controls were free of hypertension and heart disease at entry, the presence of complete right bundle branch block does not have excess mortality. Complete left bundle branch block exhibits excess total and...

Complete right bundle-branch block with right axis deviation was seen in nine patients who did not have right ventricular hypertrophy, pulmonary disease, or extensive lateral myocardial infarction. Four patients had chronic block and five had acute myocardial infarction. This pattern was attributed to a coexisting block in the right branch and in the inferior division of the left branch. It fre...