A patient with tricuspid atresia and characteristic electrocardiographic features of counterclockwise and superiorly oriented frontal plane QRS loop (left anterior hemiblock) is presented. Operative intervention resulted in a clockwise and inferior rotation of the frontal QRS loop (left posterior hemiblock) without the development of complete left bundle branch block. This observation suggests ...

Left bundle branch pacing (LBBP) is a novel technique to deliver cardiac resynchronization therapy (CRT) by correcting intrinsic LBBB achieve electrical and mechanical resynchrony. Whether the efficacy of LBBP different across morphologies has not been reported. To explore in patients with morphologies. Consecutive who received due either heart failure (HF) or atrioventricular block accompanied...

In 1909 Eppinger and Rothberger showed that characteristic changes in the electrocardiogram arose after section of the right and left branches of the bundle of His in dogs, and the following year these experimental results were applied to human pathology, so that bundle branch block became a clinical concept. Since that time the electrocardiogram originally designated right branch block has com...

This report describes tachyeardiaand bradycardia-dependent left bundle branch block in a patient who exhibited normal intraventricular conduction with impulses intermediate in timing. During bradyeardia, longer cycles were associated with increasing degrees of incomplete left bundle branch block. These clinical observations support the existence of slow Phase 4 depolarization of latent pacemake...

AIMS Left ventricular (LV) asynchrony assessment is mostly based on delays between regional myocardial velocity peaks. Regional function is barely considered. We propose apical transverse motion (ATM) as a new parameter integrating both temporal and functional information, which was tested in different conduction delays. METHODS AND RESULTS We examined 67 patients, 11 patients with post-infar...

The electrocardiogram (ECG) criteria for the left septal fascicular block (LSFB) are not universally accepted and many other denominations can be seen in literature: focal septal block, septal focal block, left septal fascicular block, left anterior septal block, septal fascicular conduction disorder of the left branch, left septal Purkinje network block, left septal subdivision block of the le...

We studied the refractoriness of Purkinje fibers with the intent of localizing critical sites of block of premature impulses. To preserve the ventricular conducting system (VCS) nearly intact in vitro, we used a modification of the Elizari preparation. This was superfused with a physiologic salt solution. Action potential durations increased progressively from the His bundle to the distal Purki...