Prevalence and Clinical Significance of Electrocardiographic Complete Right Bundle Branch Block in Young Individuals

Eur J Prev Cardiol. 2024 Feb 27:zwae082. doi: 10.1093/eurjpc/zwae082. Online ahead of print.

Abstract

Background and aims: There is limited information on the clinical significance of complete right bundle branch block (CRBBB) in young individuals. The aim of this study was to determine the prevalence and significance of CRBBB in a large cohort of young individuals aged 14-35 years old.

Methods: From 2008 to 2018, 104,369 consecutive individuals underwent a cardiovascular assessment with a health questionnaire, electrocardiogram, clinical consultation, and selective echocardiography. Follow-up was obtained via direct telephone consultations. Mean follow-up was 7.3 ± 2.7 years.

Results: CRBBB was identified in 154 (0.1%) individuals and was more prevalent in males compared with females (0.20% vs. 0.06%; p<0.05) and in athletes compared with non-athletes (0.25% vs. 0.14%; p<0.05). CRBBB-related cardiac conditions were identified in 7 (5%) individuals (4 with atrial septal defect, 1 with Brugada syndrome, 1 with progressive cardiac conduction disease and 1 with atrial fibrillation). Pathology was more frequently identified in individuals with non-isolated CRBBB compared with individuals with isolated CRBBB (14% vs 1%; p < 0.05) and in individuals with a QRS duration of ≥130 milliseconds (ms) compared with individuals with a QRS of <130ms (10% vs 1%; p<0.05).

Conclusion: The prevalence of CRBBB in young individuals was 0.1% and was more prevalent in males and athletes. CRBBB-related conditions were identified in 5% of individuals and were more common in individuals with non-isolated CRBBB and more pronounced intraventricular conduction delay (QRS duration of ≥130ms). Secondary evaluation should be considered for young individuals with CRBBB with symptoms, concerning family history, additional electrocardiographic anomalies or significant QRS prolongation (≥130ms).

Keywords: athletes; cardiovascular disease; complete right bundle branch block; young.

Plain language summary

There is limited information on the clinical significance of complete right bundle branch block (CRBBB) in young people (aged 14 to 35 years old). CRBBB is a rare finding in young individuals and is more common in male and athletic individuals. CRBBB related-conditions are found in 5% of young individuals with this electrocardiogram finding and are more common in those with additional heart symptoms, family history of premature heart disease, other abnormal electrocardiographic (ECG) findings and more pronounced forms of CRBBB (≥ 130 milliseconds). Further investigation, including at least an ultrasound of the heart (echocardiogram), is recommended for all young individuals with CRBBB with concerning symptoms, family history of heart disease, additional ECG anomalies or more pronounced CRBBB (≥130milliseconds).