Prevalence of ventricular conduction blocks in the resting electrocardiogram in a general population: The Health 2000 Survey

Aims

The prevalence of eight different ventricular conduction blocks and their association with risk factors and major cardiovascular diseases were studied in a major Finnish population study.

Methods

Data, including 12-lead electrocardiograms, were collected from 6315 subjects. The prevalence of left bundle branch block (LBBB), right bundle branch block (RBBB), non-specific ventricular block, incomplete LBBB, incomplete RBBB, R–R′-pattern, left anterior hemiblock (LAHB), and left posterior hemiblock (LPHB) was calculated for both genders in three age groups. Their association with risk factors and cardiovascular diseases was studied.

Results

R–R′-pattern was the most common ventricular conduction block in all age groups (3.9%, p < 0.001 for comparison between groups), but it showed no association with cardiovascular diseases. Males had more RBBB (1.5% vs. 0.7%, p < 0.001), incomplete LBBB (1.8 vs. 0.4, p < 0.001) and non-specific ventricular block (1.1% vs. 0.1%, p < 0.001).With increasing age (< 45 years vs. > 55 years) LBBB, RBBB and LAHB (0 vs. 2.2%, 0.3 vs. 2.2%, 0.2 vs. 1.9% respectively, p-values < 0.001) became more prevalent. LBBB, RBBB and non-specific ventricular conduction block were associated with coronary heart disease (angina pectoris in 28.3, 20.3 and 22.9%, respectively) and heart failure (25.0, 10.1 and 11.4%, respectively). LBBB and RBBB were also associated with peripheral vascular disease (8.8%).

Conclusions

Ventricular conduction blocks differ in prevalence between sexes and age groups. They also show disparate association with cardiovascular diseases. These differences need to be taken into consideration in everyday clinical practice.