Low-Flow, Low-Gradient Severe Aortic Stenosis Despite Normal Ejection Fraction Is Associated with Severe Left Ventricular Dysfunction as Assessed by Speckle-Tracking Echocardiography: A Multicenter Study.
Circ Cardiovasc Imaging. 2011 Nov 22;
Authors: Adda J, Mielot C, Giorgi R, Cransac F, Zirphile X, Donal E, Sportouch-Dukhan C, Réant P, Lafitte S, Cade S, Le Dolley Y, Thuny F, Touboul N, Lavoute C, Avierinos JF, Lancellotti P, Habib G
BACKGROUND: -Low-flow low-gradient (LFLG) is sometimes observed in severe aortic stenosis (AS) despite normal ejection fraction (EF), but its frequency and mechanisms are still debated. We aimed to describe the characteristics of patients with LFLG AS and assess the presence of longitudinal LV dysfunction in these patients. METHODS AND RESULTS: -In a multicentre prospective study, 340 consecutive patients with severe AS and normal EF were studied. Longitudinal LV function was assessed by 2D-strain and global afterload by valvulo-arterial impedance (Zva). Patients were classified according to flow and gradient: low flow was defined as a stroke volume index ?35 ml/m(2), low gradient as a mean gradient ?40 mmHg. Most patients (n=258, 75.9%) presented with high gradient AS and 82 patients (24.1%) with low gradient AS. Among the latter, 52 (15.3%) presented with normal flow and low gradient (NFLG), 30 (8.8%) with low flow and low gradient (LFLG). As compared with NFLG, patients with LFLG had more severe AS (AVA=0.7 ±0.12 cm(2) vs 0.86 ±0.14 cm(2)), higher Zva (5.5±1.1 vs 4±0.8 mmHg/ml/m(2)) and worse longitudinal LV function (basal longitudinal strain = -11.6 ± 3.4 vs -14.8 ± 3 %)(p <0.001 for all). CONCLUSIONS: -LFLG AS is observed in 9% of patients with severe AS and normal EF and is associated with high global afterload and reduced longitudinal systolic function. Patients with NFLG AS are more frequent and present with less severe AS, normal afterload, and less severe longitudinal dysfunction. Severe LV longitudinal dysfunction is a new explanation to the concept of LFLG AS.
PMID: 22109983 [PubMed - as supplied by publisher]