Preoperative Main Pulmonary Artery Diameter Indexed to Body Surface Area Independently Predicts Mortality After...

Pulmonary hypertension (PH) commonly accompanies severe aortic stenosis and adversely affects outcomes after transcatheter aortic valve implantation (TAVI). However, the prognostic value of computed tomography-derived pulmonary artery remodeling, particularly the main pulmonary artery diameter (mPAD) indexed to body surface area (mPAD/BSA), remains uncertain. Therefore, this study aimed to investigate the prognostic significance of mPAD/BSA in patients with severe aortic stenosis and concomitant PH undergoing TAVI.

We retrospectively analyzed 122 consecutive patients undergoing TAVI, while the subgroup of 103 patients referred to those with pulmonary hypertension. Pulmonary artery systolic pressure (PASP) was estimated by transthoracic echocardiography, while mPAD was quantified on multidetector computed tomography (MDCT) and indexed to BSA. Patients were stratified according to postoperative changes in PASP. Echocardiographic and imaging parameters were compared across PH severity categories.

Postoperative PASP improvement was observed in 71 patients (68.9%). Patients with PASP improvement had smaller baseline mPAD and mPAD/BSA but higher baseline PASP than those who showed no improvement (all p < 0.05). Although PASP improved in patients with pre-existing PH, the extent and trajectory of recovery varied according to baseline PH severity. In contrast, left ventricular hemodynamics improved uniformly across all groups, whereas right heart remodeling and pulmonary artery structural changes remained limited. In the multivariable logistic regression analysis, baseline atrial fibrillation (AF) (p = 0.009), preoperative first-degree atrioventricular block (AVB) (p = 0.032), and preoperative ≥ moderate tricuspid regurgitation (TR) (p = 0.037) were independently associated with a lower risk of postoperative PASP non-improvement. In contrast, preoperative ≥ moderate aortic regurgitation was associated with a higher risk of PASP non-improvement (p = 0.022). Notably, preoperative MDCT-derived mPAD/BSA independently predicted 1-year all-cause mortality (HR 1.29, 95% CI 1.01-1.64; p = 0.041), providing incremental prognostic information alongside echocardiographic PASP.

PH secondary to aortic stenosis is only partially reversible after TAVI, with greater improvement in mild-to-moderate disease. Preoperative mPAD/BSA is a novel MDCT-based structural biomarker that independently predicts 1-year all-cause mortality beyond PASP alone. Integrating pulmonary vascular imaging with echocardiography may improve risk stratification and inform procedural timing in patients undergoing TAVI.