Evaluation of Right and Left Ventricular Deformation Analysis in İdiopathic Right Bundle Branch Block by Speckle...

Idiopathic right bundle branch block (RBBB) is often seen as harmless and common. However, many studies show it might be linked to negative health outcomes. So, it is crucial to fully understand how RBBB affects the heart's ventricles.

This study aims to examine the right and left ventricular systolic functions in patients with idiopathic RBBB and compare them to those in a healthy control group.

Echocardiographic images were obtained from patients with idiopathic RBBB and healthy control participants. Conventional echocardiographic parameters were measured. Two-dimensional (2D) speckle tracking strain analysis was used to assess deformation indices.

Thirty-nine patients with idiopathic RBBB and 35 healthy participants were included in the study. There were no significant differences in the chamber dimensions of the left ventricle (LV) and right ventricle (RV) between the groups. LV ejection fraction (EF), RV fractional area change (FAC), and tricuspid annular plane systolic excursion (TAPSE) measurements were similar between the groups. LV global longitudinal strain (GLS) (-25.5 ± 5.7% vs. -22.1 ± 4.2%, p < 0.05), RV GLS (-26.9 ± 4.6% vs. -24.0 ± 4.4%, p < 0.05), and interventricular septum longitudinal strain (IVS LS) (-24.3 ± 4.9% vs. -19.1 ± 4.2%, p < 0.05) were significantly reduced in patients with idiopathic RBBB compared to controls, indicating impaired myocardial shortening. Significant differences were also observed in LV (15 [5-30] vs. 30 [20-60], p < 0.05) and RV (18 [7-35] vs. 36 [24-80], p < 0.05) mechanical dispersion, with the differences being more pronounced for the RV between the groups. LV torsion (2.1 ± 0.6 vs. 1.6 ± 0.5, p < 0.05) was also worse in patients with idiopathic RBBB.

Our findings show that idiopathic RBBB significantly affects the longitudinal strain and synchronization of both the LV and RV.