Effects of an Isolated Complete Right Bundle Branch Block on Mechanical Ventricular Function

Double outlet right ventricle in adults: Anatomic variability, surgical treatment, and late postoperative complications

Double outlet right ventricle (DORV) is a highly complex congenital heart disease (CHD) entity, gaining increasing interest due to the rapid progress of cardiac surgery. The number of patients operated for this congenital defect has been growing since 1980s and over following decades with active transitioning of this cohort into the adult medicine. However, the diversity of initial anomaly and performed interventions makes challenging the management of these patients. This is particularly important in the regions where specialized adult CHD cardiology still remains underdeveloped. In this review, we observe the basic principles of DORV nomenclature, main types of the operations and possible late complications. The article focuses on adult patients and offers illustrations from clinical practice.

Mortality in Patients With Right Bundle-Branch Block in the Absence of Cardiovascular Disease

Background Right bundle-branch block (RBBB) occurs in 0.2% to 1.3% of people and is considered a benign finding. However, some studies have suggested increased risk of cardiovascular morbidity and mortality. We sought to evaluate risk attributable to incidental RBBB in patients without prior diagnosis of cardiovascular disease (CVD). Methods and Results We reviewed the Mayo Clinic Integrated Stress Center database for exercise stress tests performed from 1993 to 2010. Patients with no known CVD-defined as absence of coronary disease, structural heart disease, heart failure, or cerebrovascular disease-were selected. Only Minnesota residents were included, all of whom had full mortality and outcomes data. There were 22 806 patients without CVD identified; 220 of whom (0.96%) had RBBB, followed for 6 to 23 years (mean 12.4±5.1). There were 8256 women (36.2%), mean age was 52±11 years; and 1837 deaths (8.05%), including 645 cardiovascular-related deaths (2.83%), occurred over follow-up. RBBB was predictive of all-cause (hazard ratio [HR], 1.5; 95% CI, 1.1-2.0; P=0.0058) and cardiovascular-related mortality (HR,1.7; 95% CI, 1.1-2.8; P=0.0178) after adjusting for age, sex, diabetes mellitus, hypertension, obesity, current and past history of smoking, and use of a heart rate-lowering drug. Patients with RBBB exhibited more hypertension (34.1% versus 23.7%, P<0.0003), decreased functional aerobic capacity (82±25% versus 90±24%; P<0.0001), slower heart rate recovery (13.5±11.5 versus 17.1±9.4 bpm; P<0.0001), and more dyspnea (28.2% versus 22.4%; P<0.0399) on exercise testing. Conclusions Patients with RBBB without CVD have increased risk of all-cause mortality, cardiovascular-related mortality, and lower exercise tolerance. These data suggest RBBB may be a marker of early CVD and merit further prospective evaluation.

The phenomenon of concealed conduction in a case of His bundle pacing (HBP)

The phenomenon of concealed conduction in His bundle pacing (HBP) has rarely been reported. We report here a patient who had 2: 1 atrioventricular block and complete left bundle branch block was used because of HBP. The patient developed continuous right bundle branch block after the operation. After excluding mechanical damage, we speculate that the mechanism of right bundle branch block in this case was due to concealed conduction.