Abstract Body (Do not enter title and authors here): Background: The pulmonary artery to ascending aorta ratio (PA/Ao), measurable by chest computed tomography (CT) was associated with clinical outcomes in patients with heart failure (HF). However, it is unclear whether the preprocedural PA/Ao is associated with postprocedural clinical outcomes in patients undergoing transcatheter edge-to-edge repair (M-TEER).
Methods: We retrospectively examined 73 consecutive patients who underwent M-TEER for severe mitral regurgitation between April 2020 and March 2025. Chest CT performed within 3 months before the procedure was used to measure the diameters of the main PA and Ao. Transverse axial main pulmonary arterial diameter and minimum ascending aortic diameter were both measured at the level of PA bifurcation (Figure 1). The PA/Ao was calculated as the former divided by the latter. Patients were divided into two groups: higher PA/Ao (≥1.0) and lower PA/Ao (<1.0). The primary outcome was a composite of all-cause death and hospitalization for worsening HF.
Results: The median age was 77 years, and 36 patients (49.3%) were male. The median left ventricular ejection fraction (LVEF) was 33%. The median PA diameter, Ao diameter, and PA/Ao were 29mm, 35mm, and 0.85, respectively. There were no significant differences in age, LVEF, renal function, mitral effective regurgitant orifice area, left ventricular end-diastolic volume index, and N-terminal pro–B-type natriuretic peptide level between the groups. Patients with higher PA/Ao showed higher mean PA pressure and pulmonary capillary wedge pressure compared to those with lower PA/Ao. During a median follow-up of 541 (interquartile range 245–1101) days, the primary outcome occurred in 26 patients. Patients with higher PA/Ao had significantly higher incidence of the primary outcomes compared to those with lower PA/Ao (Figure 2). A multivariable Cox regression analysis showed that higher PA/Ao was independently associated with a higher risk of primary outcome even after adjustment for prognostic covariates including age and LVEF (hazard ratio 4.18, 95% confidence interval 1.85-9.44, P = 0.001).
Conclusions: A higher preprocedural PA/Ao ratio measured by chest CT was independently associated with an increased risk of adverse events in patients undergoing M-TEER, highlighting its potential role as a simple imaging-based prognostic surrogate in this population.