Abstract
Aortic valve calcium scoring by cardiac computed tomographic (CT) has been recommended as an alternative to classify the AS severity, but it is unclear that whether CT findings can predict and have prognostic implication in low-flow, low-gradient aortic stenosis (LF-LG AS), which has fewer benefit from surgery among the AS subtypes. In this study, we examined the clinical and cardiac CT findings of LF-LG AS patients and evaluated factors affecting outcomes after surgical aortic valve replacement (AVR). This study included 511 (66.9±8.8 years, 55% men) consecutive patients with severe AS who underwent surgical AVR. Aortic valve area (AVA) was obtained by echocardiography (AVAecho) and by CT (AVACT) using each modalities measurement of the left ventricular outflow tract. Patients with AS were classified as 1) high-gradient severe (n=438), 2) classic LF-LG (n=18), and 3) paradoxical LF-LG (n=55) based on echocardiography. Classic LF-LG AS patients had higher end-systolic and end-diastolic volume indices, lower left ventricular ejection fraction, larger AVAecho and AVACT, and larger aortic annulus compared to high-gradient severe AS (P<0.05, for all). In classic LF-LG AS group, 27.8% of patients presented AVACT≥1.2 cm2. After multivariable adjustment, old age (hazard ratio [HR], 1.04, P=0.049), high B-type natriuretic peptide (BNP) (HR, 1.005; P<0.001), preoperative atrial fibrillation (HR, 2.75; P=0.003), classic LF-LG AS (HR, 5.53, P=0.004), and small aortic annulus (HR, 0.57; P=0.002) were independently associated with major adverse cardiac and cerebrovascular events (MACCE). The classic LF-LG AS group presented larger AVACT and aortic annulus than those in high-gradient severe AS group and one third of them had AVACT ≥1.2 cm2. Old age, high BNP, atrial fibrillation, classic LF-LG AS, and small aortic annulus were associated with MACCE in severe AS patients after surgical AVR.
Can left ventricular longitudinal function study using 2D speckle tracking predict postoperative atrial fibrillation after aortic valve replacement for aortic stenosis?
