Computed Tomography Scan Predictors and Prognostic Impact of Combined Pulmonary Hypertension in Patients With Aortic Valve Stenosis undergoing TAVI

Precapillary (PrPH) and combined pre and postcapillary pulmonary hypertension (CoPH) increase all-cause and cardiovascular mortality risk in patients undergoing TAVI for severe symptomatic aortic stenosis. Since pulmonary artery (PA) diameter adapts to increased pulmonary artery pressure, this study evaluates the correlation between CT-derived main PA (MPA), right PA (RPA), left PA (LPA) diameters, and the MPA/ascending aorta (AA) ratio with PH subtypes defined by right heart catheterization (RHC), as well as their prognostic impact. This retrospective study includes all consecutive patients undergoing TAVR between June 2007 to December 2022 with pre-TAVI RHC and ECG-gated CT scans. The primary endpoint was all-cause mortality. Mean follow-up time was 5 years. Among 638 consecutive patients, 329 (51%) had normal mPAP, while 309 (49%) had PH. Of these, 143 (46%) had isolated postcapillary PH (IpcPH), and 166 (54%) had CoPH. Patients with PrPH were excluded. CoPH patients had higher PAP than both IpcPH and no-PH groups. In univariable and multivariable analysis, MPA, MPA index (MPAi), RPA, RPA index (RPAi), MPA/AA, MPAi/AA, and RPA/LPA correlated with PH, while MPA, MPAi, RPA, RPAi, MPA/AA, and MPAi/AA were associated with CoPH. The best AUC for PH discrimination was MPAi (AUC = 0.71, cutoff = 16 mm/m², sensitivity = 66%, specificity = 72%), while MPA/AA best discriminated CoPH (AUC = 0.73, cutoff = 0.88, sensitivity = 67%, specificity = 72%). Patients with PA/AA <0.88 had significantly lower 5-year mortality after TAVI than those with PA/AA ≥0.88 (log-rank p = 0.046, HR 1.39). In conclusion, Increase in MPA/AA CT-derived ratio is predictive of Combined PH, highlighting patients who could benefit from a RHC in term of CV stratification before TAVI.