Electrical and mechanical dyssynchrony in pre-capillary pulmonary hypertension without complete bundle branch block: a comparison between electrocardiogram and two-dimensional echocardiography

Background:To explore the correlation between electrical and mechanical dyssynchrony of right ventricle (RV)in pre-capillary pulmonary hypertension (PcPH) patients, and further compare their capability in predicting risk stratification. Methods: We consecutively enrolled PcPH patients at Fuwai Hospital from April 2017 to March 2018, then classified them into low and non-low risk groups based on recommendations of 2015 European Society of Cardiology Guidelines. RV mechanical dyssynchrony were measured using off-line softwares (GE EchoPAC version 201), referred to as RV-SD6. Electrical dyssynchrony, represented as QRS duration, was measured manually from the chest lead V2 with electronic calipers. Results: Sixty-six PcPH patients (average 35 years, 19 males and 47 females) were finally enrolled, 37 in low-risk group, while 29 in non-low-risk group. QRS duration was significantly correlated with RV-SD6 (r = 0.25, P = 0.047). Both RV-SD6 and QRS duration significantly correlated with N-terminal pro-brain natriuretic peptide (r = 0.44, P＜0.001 vs r = 0.26, P = 0.039). Furthermore, RV-SD6 (area under curve, AUC 0.75, 95% CI 0.64–0.87, P ＜0.001) and QRS duration (AUC 0.65, 95% CI 0.52–0.78, P = 0.036) both had the potential to predict non-low risk stratification. Multivariate Logistic regression analyses identified RV-SD6 (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 of PcPH patients. Conclusion: RV mechanical dyssynchrony presented by RV-SD6 correlates with QRS duration and has a better capability in predicting risk stratification in PcPH patients without complete bundle branch block.