Right ventricular-pulmonary artery coupling as a tool for clinical prioritization in severe aortic stenosis
M Duarte Almeida, J G Fiuza, F R Santos, O C Kungel, L A Santos, G R M Ferreira, N CraveiroAbstract
Introduction
Severe high-gradient aortic stenosis (AS) induces progressive left-heart pressure overload, eventually impacting pulmonary circulation and right ventricular (RV) function. The TAPSE/PASP ratio is an emerging non-invasive surrogate for RV-pulmonary artery (RV-PA) coupling. Given the challenge of prolonged waiting lists, identifying markers of hemodynamic uncoupling is paramount to stratify patients at higher risk of clinical deterioration, allowing for precise prioritization beyond traditional valvular gradients.
Purpose
To evaluate the prognostic value of RV-PA coupling, assessed by the TAPSE/PASP ratio, in patients with severe high-gradient AS awaiting intervention.
Methods
Patients who underwent transthoracic echocardiography from January to December 2022 with severe high-gradient AS and referred for valve intervention were included. The primary composite endpoint was defined as all-cause mortality, unplanned hospitalization, or emergency department visits requiring intravenous diuretics for decompensated heart failure within one year of referral (or until intervention). RV-PA coupling was quantified by the TAPSE/PASP ratio for all patients. Group comparisons were performed using the Mann-Whitney U test. Predictive performance was analysed using ROC curves and logistic regression.
Results
A total of 95 patients were included (48.4% female; mean age 75.5 ± 8.0 years). The primary endpoint occurred in 21.1% (n=20) of the patients. The TAPSE/PASP ratio was significantly lower in those with adverse outcomes (median 0.49, IQR 0.34–0.63) compared to those without (median 0.70, IQR 0.52–0.79), p=0.011. ROC analysis showed moderate discriminatory capacity (AUC 0.721; 95% CI: 0.574–0.869; p=0.011), with an optimal cut-off of 0.51 (Sensitivity 79%, Specificity 64%). In logistic regression, a TAPSE/PASP ratio ≤0.51 was associated with a 6.1-fold increase in the odds of reaching the primary endpoint (OR 6.1; 95% CI: 1.74–21.40; p=0.005).
Conclusion
A TAPSE/PASP ratio ≤0.51 is a powerful and accessible predictor of adverse events in patients with severe AS. This non-invasive marker of RV-PA coupling can be a valuable tool for risk stratification and prioritization of patients on surgical or transcatheter intervention waiting lists.For image description, please refer to the figure legend and surrounding text.