or even complete A-V block. Two cases are reported in which catheter-induced transient high grade Mobitz II A-V block, acute reversible prolongation of infranodal conduction time with probable intra-Hisian conduction delay, and persistent (6 hours duration) complete A-V block occurred in patients with left bundle branch block. The observations made indicate that A-V conduction times and the app...

Despite the major advances in medical drug therapy, heart failure remains a syndrome associated with high mortality and morbidity. Biventricular or left ventricular (LV) short atrioventricular (AV) delay pacing is being tested in congestive heart failure patients with left bundle branch block. The aim is to resynchronise the dyscoordinate LV contraction. A number of studies are underway, but it...

Right bundle branch block is an electrocardiographic phenomenon with specific criteria.Currently, two specific forms of right bundle branch block are acknowledged, a proximal and a distal variant. A vast array of pathologies can cause proximal, distal or even combined forms of right bundle branch block.IN THIS STUDY IT IS SUGGESTED THAT A THIRD TYPE OF RIGHT BUNDLE BRANCH BLOCK EXIST: one cause...

Lyme disease may present with a variety of cardiac manifestations ranging from first degree to third degree heart block. Cardiac involvement with Lyme disease may be asymptomatic, or symptomatic. Atrioventrical conduction abnormalities are the most common manifestation of Lyme carditis. Less common, are alternating right bundle branch block (RBBB) and left bundle branch block (LBBB). We present...

The PR interval represents the time from the beginning of the P wave (atrial excitation) to the beginning of the QRS complex (ventricular excitation). Taking an average PR interval of 0.16 sec., let us dissect it into its component parts. The impulse from the SA node spreads down the three atrial specialized tracts and through the atrial myocardium to reach the AV node. The atrial myocardial ex...

It has been demonstrated repeatedly that not much importance c attached to the prognostic significance of bundle branch block. Right I branch block has been considered to show a more favorable proj than left bundle branch block. However, the presence of right I branch block, either the typical or atypical form, alerts the physici the basic cardiac disease, particularly disease of the coronary c...