The complex nature of discordant severe calcified aortic valve disease grading : new insights from combined Doppler echocardiographic and computed tomographic study

Authors: Clavel, Marie-Annick; Messika-Zeitoun, David; Pibarot, Philippe; Aggarwal, Shivani R.; Malouf, Joseph; Araoz, Philip A.; Michelena, Hector I.; Cueff, Caroline; Larose, Éric; Capoulade, Romain; Vahanian, Alec; Enriquez-Sarano, Maurice
Abstract: Objectives With concomitant Doppler echocardiography and multidetector computed tomography (MDCT) measuring aortic valve calcification (AVC) load, this study aimed at defining: 1) independent physiologic/structural determinants of aortic valve area (AVA)/mean gradient (MG) relationship; 2) AVC thresholds best associated with severe aortic stenosis (AS); and 3) whether, in AS with discordant MG, severe calcified aortic valve disease is generally detected. BackgroundAortic stenosis with discordant markers of severity, AVA in severe range but low MG, is a conundrum, unresolved by outcome studies. MethodsPatients (n = 646) with normal left ventricular ejection fraction AS underwent Doppler echocardiography and AVC measurement by MDCT. On the basis of AVA-indexed-to-body surface area (AVAi) and MG, patients were categorized as concordant severity grading (CG) with moderate AS (AVAi >0.6 cm²/m², MG <40 mm Hg), severe AS (AVAi =0.6 cm²/m², MG = 40 mm Hg), discordant-severity-grading (DG) with low-MG (AVAi =0.6 cm2/m2, MG <40 mm Hg), or high-MG (AVAi >0.6 cm2/m2, MG =40 mm Hg). ResultsThe MG (discordant in 29%) was strongly determined by AVA and flow but also independently and strongly influenced by AVC-load (p < 0.0001) and systemic arterial compliance (p < 0.0001). The AVC-load (median [interquartile range]) was similar within patients with DG (low-MG: 1,619 [965 to 2,528] arbitrary units [AU]; high-MG: 1,736 [1,209 to 2,894] AU; p = 0.49), higher than CG-moderate-AS (861 [427 to 1,519] AU; p < 0.0001) but lower than CG-severe-AS (2,931 [1,924 to 4,292] AU; p < 0.0001). The AVC-load thresholds separating severe/moderate AS were defined in CG-AS with normal flow (stroke-volume-index >35 ml/m2). The AVC-load, absolute or indexed, identified severe AS accurately (area under the curve =0.89, sensitivity =86%, specificity =79%) in men and women. Upon application of these criteria to DG-low MG, at least one-half of the patients were identified as severe calcified aortic valve disease, irrespective of flow. ConclusionsAmong patients with AS, MG is often discordant from AVA and is determined by multiple factors, valvular (AVC) and non-valvular (arterial compliance) independently of flow. The AVC-load by MDCT, strongly associated with AS severity, allows diagnosis of severe calcified aortic valve disease. At least one-half of the patients with discordant low gradient present with heavy AVC-load reflective of severe calcified aortic valve disease, emphasizing the clinical yield of AVC quantification by MDCT to diagnose and manage these complex patients.
Document Type: Article de recherche
Issue Date: 17 December 2013
Open Access Date: Restricted access
Document version: VoR
This document was published in: Journal of the American College of Cardiology, Vol. 62 (24), 2329–2338 (2013)
Elsevier Biomedical
Alternative version: 10.1016/j.jacc.2013.08.1621
Collection:Articles publiés dans des revues avec comité de lecture

Files in this item:
516.46 kBAdobe PDF    Request a copy
All documents in CorpusUL are protected by Copyright Act of Canada.