Background—Clinical trials of cardiac resynchronization therapy (CRT) have enrolled a select group of patients, with few patients in subgroups such as right bundle-branch block (RBBB). Analysis of population-based outcomes provides a method to identify real-world predictors of CRT outcomes. Methods and Results—Medicare Implantable Cardioverter-Defibrillator Registry (2005 to 2006) data were mer...

BACKGROUND We evaluated the risk of incident heart failure (HF) associated with bundle-branch blocks (BBBs) in postmenopausal women. METHODS AND RESULTS Cox's regression was used to evaluate hazard ratios with 95% confidence intervals for HF among 65975 participants of the Women's Health Initiative (WHI) study during an average follow-up of 14 years. BBBs observed in 1676 women at baseline we...

AIMS To determine the prevalence, predictors of newly acquired, and the prognostic value of right bundle branch block (RBBB) and incomplete RBBB (IRBBB) on a resting 12-lead electrocardiogram in men and women from the general population. METHODS AND RESULTS We followed 18 441 participants included in the Copenhagen City Heart Study examined in 1976-2003 free from previous myocardial infarctio...

Two hundred and forty-three patients were evaluated following total correction of tetralogy of Fallot with special emphasis on postoperative conduction disturbances and on the occurrence of sudden death. The average follow-up period was 12 years with a range of 6 1/2 to 16 1/2 years. Sudden death occurred in seven patients. Four deaths were among those with right bundle branch block pattern (RB...

The electrocardiogram in 480 patients with acute myocardial infarction showed right bundle-branch block (RBBB) with normal QRS axis in 18 patients (3.7%), left bundle-branch block (LBBB) in 31 (8%), RBBB and left anterior hemiblock (LAH) in 23 (4.8%), RBBB and left posterior hemiblock (LPH) in four (1%), LAH alone in 20 (4%), LPH in one (0.2%), and no evidence of intraventricular conduction (I-...

SUMMARY The time intervals defined by the simultaneous recording of an electrocardiogram, phonocardiogram, indirect carotid pulse curve, and apexcardiogram made it possible to compare the left ventricular (LV) dynamics in a group of 33 cases of complete right bundle-branch block with left axis deviation (RBBB-LAD) with two control groups, one consisting of 30 cases of complete right bundle-bran...

The electrocardiogram in 480 patients with acute myocardial infarction showed right bundle-branch block (RBBB) with normal QRS axis in 18 patients (3.7%), left bundle-branch block (LBBB) in 31 (8%), RBBB and left anterior hemiblock (LAH) in 23 (4.8%), RBBB and left posterior hemiblock (LPH) in four (1%), LAH alone in 20 (4%), LPH in one (0.2%), and no evidence of intraventricular conduction (I-...

Three cases in which left anterior hemiblock (LAH) obscured the diagnosis of right bundle branch block (RBBB) are reported. The RBBB was incomplete in one case and complete or of high degree in the other two. The LAH was intermittent in two cases. In the three cases, the LAH abolished not only the S waves in leads I and aVL, but also the terminal R wave in Vl. The possibility that RBBB, complet...

Chagas disease (CD) affects over six million people and is a leading cause of cardiomyopathy in Latin America. Given recent migration trends, there is a large population at risk in the United States (US). Early stage cardiac involvement from CD usually presents with conduction abnormalities on electrocardiogram (ECG) including right bundle branch block (RBBB), left anterior or posterior fascicu...

BACKGROUND Clinical trials of cardiac resynchronization therapy (CRT) have enrolled a select group of patients, with few patients in subgroups such as right bundle-branch block (RBBB). Analysis of population-based outcomes provides a method to identify real-world predictors of CRT outcomes. METHODS AND RESULTS Medicare Implantable Cardioverter-Defibrillator Registry (2005 to 2006) data were m...