Electrical-mechanical dyssynchrony in pre-capillary pulmonary hypertension

Area of Science:

• Cardiology
• Pulmonary Hypertension
• Echocardiography

Background:

• Pre-capillary pulmonary hypertension (PcPH) presents complex challenges in risk stratification.
• Understanding the interplay between electrical and mechanical cardiac function is crucial for managing PcPH.
• Right ventricular (RV) dyssynchrony, both electrical and mechanical, is increasingly recognized as a significant factor.

Purpose of the Study:

• To investigate the correlation between RV electrical and mechanical dyssynchrony in PcPH patients.
• To compare the predictive value of these dyssynchronies for risk stratification.
• To identify independent predictors of adverse outcomes in PcPH.

Main Methods:

• Prospective enrollment of 66 PcPH patients, categorized into low-risk and non-low-risk groups.
• Measurement of RV mechanical dyssynchrony using RV-SD6 (standard deviation of time from QRS onset to peak strain).
• Assessment of electrical dyssynchrony via QRS duration, with correlation analysis against clinical markers and risk stratification.

Main Results:

• A significant correlation was found between QRS duration and RV-SD6 (r=0.25, p=0.047).
• Both RV-SD6 and QRS duration correlated with N-terminal pro-brain natriuretic peptide levels.
• RV-SD6 (AUC=0.75) and QRS duration (AUC=0.65) predicted non-low-risk stratification, with RV-SD6 identified as an independent predictor (OR=1.02).

Conclusions:

• Mechanical dyssynchrony (RV-SD6) is correlated with electrical dyssynchrony (QRS duration) in PcPH.
• RV-SD6 demonstrates superior predictive capability for risk stratification compared to QRS duration alone in PcPH patients without complete bundle branch block.