Electrical-mechanical dyssynchrony in pre-capillary pulmonary hypertension

This study focused on exploring the correlation between the electrical and mechanical dyssynchrony of the right ventricle (RV) in patients with pre-capillary pulmonary hypertension (PcPH). It also aimed to compare the predictive capabilities of these dyssynchronies for risk stratification.

From April 2017 to March 2018, PcPH patients at Fuwai Hospital were consecutively enrolled. They were divided into low-risk and non-low-risk groups according to the 2015 European Society of Cardiology Guidelines. Off-line software (GE EchoPAC version 201) was used to measure RV mechanical dyssynchrony (standard deviation of the time from QRS onset to peak strain for the six RV segments [RV-SD6]), while QRS duration representing electrical dyssynchrony was measured manually.

In total, 66 PcPH patients (average 35 years, 19 males and 47 females) were enrolled, 37 in the low-risk group and 29 in the non-low-risk group. QRS duration was significantly correlated with RV-SD6 (r = 0.25, p = 0.047). Both RV-SD6 and QRS duration were significantly correlated with N‑terminal pro-brain natriuretic peptide levels (r = 0.44, p < 0.001 vs. r = 0.26, p = 0.039). Furthermore, RV-SD6 (area under the curve [AUC]: 0.75, 95% confidence interval [CI]: 0.64-0.87, p < 0.001) and QRS duration (AUC: 0.65, 95% CI: 0.52-0.78, p = 0.036) had the potential to predict non-low-risk stratification. Multivariate logistic regression analyses identified RV-SD6 (odds ratio [OR]: 1.02, 95% CI: 1.01-1.03, p = 0.009) and QRS duration (OR: 1.07, 95% CI: 1.00-1.15, p = 0.045) as independent predictors of non-low-risk PcPH.

Mechanical dyssynchrony presented by RV-SD6 correlates with QRS duration and better predicts risk stratification in PcPH patients without complete bundle branch block.