CT measured pulmonary artery to ascending aorta ratio stratified by echocardiographically obtained systolic pulmonary artery pressure values for noninvasive detection of pulmonary hypertension in patients with severe aortic valve stenosis.

Abstract

Transthoracic echocardiography (TTE) offers a measurement method for the determination of pulmonary hypertension (PH) in patients with severe aortic valve stenosis (AS) with determination of maximal tricuspid regurgitation velocity (TRVmax) and systolic pulmonary artery pressure (sPAP). Radiological parameters for noninvasive detection of PH, most importantly computed tomography (CT) based PA/AA-ratio = ratio of pulmonary artery diameter (PA) and ascending aorta diameter (AA), are also included in the latest ESC guidelines. The aim of the present study was to define cut-off values for PA/AA-ratio taking also into account cardiovascular biomarkers to determine criteria for noninvasive diagnosis of PH. 194 patients with severe AS undergoing transcatheter aortic valve replacement (TAVR) underwent pre-procedural TTE and CT with measurement of PA/AA-ratio. Additionally, common cardiovascular biomarkers were determined. TAVR patients with an sPAP ≥ 40mmHg or a TRVmax ≥ 2.9m/s had a PA/AA-ratio ≥ 0.80 in an AUROC analysis. The cut-off value of ≥ 0.80 resulted in a significantly higher mortality rate (log-rank test: p = 0.034) in these patients in a Kaplan-Meier analysis regarding 1-year survival after TAVR. Significant differences in biomarker expression between patients with a PA/AA-ratio ≥ 0.80 or < 0.80 occurred for BNP (p = 0.001), cTnI (p = 0.032), GDF-15 (p = 0.002) and H-FABP (p = 0.015). PA/AA-ratio ≥ 0.80 is a promising radiological parameter that can provide information about mortality in patients with severe AS undergoing TAVR; combined with biomarkers it may contribute to noninvasive detection of PH in patients with severe AS.