Right ventricular-pulmonary artery coupling in patients undergoing cardiac resynchronization therapy.

Background: The ratio between tricuspid annular plane systolic excursion (TAPSE) and estimated pulmonary artery systolic pressure (PASP) has been shown to be a reliable, non-invasive surrogate of the right ventricular-pulmonary artery (RV-PA) coupling. The present study analysed the association between TAPSE/PASP and response to cardiac resynchronization therapy (CRT) and the prognostic role of RV-PA in patients undergoing CRT implantation. The primary endpoints were: the association between baseline TAPSE/PASP and CRT response/cardiovascular and all-cause death.

Results: All patients having undergone CRT implantation in our Center from 2016 to 2020 were included in our retrospective analysis. The RV-PA coupling was assessed by echocardiography at baseline and 1 year follow up in CRT recipients. The cut-off value of TAPSE/PASP resulted from ROC curve analysis (i.e.<0.33 mm/mmHg). A total of 229 patients (age 69.9 ± 10.1 years; 77.7% men) were included. During a mean follow-up of 44.2 ± 17.9 months, 40 (17.5%) patients died. The baseline value of TAPSE/PASP was not significantly associated with CRT response. Patients with a more impaired TAPSE/PASP ratio had significantly worse survival rates. On multivariate Cox regression, only TAPSE/PASP ratio and estimated glomerular filtration rate were independently associated with all-cause death. Finally, the TAPSE/PASP ratio significantly increased after CRT implantation in the group of "responders" whereas it did not change in 'non-responders'.

Conclusions: The baseline value of TAPSE/PASP ratio was not associated with CRT response. However, the TAPSE/PASP ratio was a strong predictor of both all-cause and cardiovascular death in CRT recipients.