P=0.22).
Conclusions-AVR
Ozkan et al AVR and Low-Gradient Severe AS 623We sought to compare the outcome of LGSAS patients who underwent AVR with those who received medical therapy.
Methods
Patient SelectionWe studied 1745 patients with symptomatic severe AS, based on AVA ≤1 cm 2 /m 2 , referred to our center from 2006 to 2011 for highrisk AS management (including possible valve replacement with either transcatheter AVR [TAVR] or surgical AVR [SAVR]). After exclusion of 157 patients with severe mitral or aortic valvular regurgitation, severe mitral stenosis, prosthetic heart valves, history of previous balloon aortic valvuloplasty, and indexed AVA >0.6 cm 2 /m 2 , a prospective group of 1588 patients with symptomatic severe AS (indexed AVA ≤0.6 cm 2 /m 2 ) was evaluated, of whom 260 (16%) had low transvalvular gradients (mean gradient <40 mm Hg; Figure 1). The study protocol was approved by the Institutional Review Board at the Cleveland Clinic.
Clinical EvaluationAll 260 patients with LGSAS underwent a comprehensive medical history and physical examination. Angina was classified by Canadian Cardiovascular Society classification, dyspnea was evaluated by New York Heart Association class, and history of syncope was sought carefully. Demographic data, including age, sex, body mass index, and body surface area (BSA), and comprehensive clinical data, including history of hypertension, diabetes mellitus, dyslipidemia, smoking, coronary artery disease, peripheral arterial disease, prior myocardial infarction, and coronary artery bypass surgery, were collected. Current medications used by these patients were recorded.Systolic and diastolic blood pressures were measured at the time of echocardiographic examination, and mean arterial pressure was calculated. Society of Thoracic Surgery (STS) scores were calculated with an online risk calculator (http://riskcalc.sts.org/ STSWebRiskCalc273/).
Echocardiographic AssessmentComprehensive baseline transthoracic echocardiograms that included standard M-mode, 2-dimensional color Doppler and pulsed-wave and continuous-wave Doppler were performed with commercially available systems. Left ventricular (LV) dimensions, volumes, and ejection fraction (using the biplane Simpson method), fractional shortening, LV mass, and relative wall thickness were calculated in accordance with the current recommendations.3 LV mass was indexed to BSA, and LV hypertrophy was defined as LV mass index >115 g/m 2 in men and >95 g/m 2 in women. LV midwall fractional shortening (MWFS) was also calculated from the formula MWFS=100×[(LVIDd/2+PWTd /2)−(LVIDs/2+PWTs/2)]/(LVIDd/2+PWTd/2), in which LVIDd is LV internal diameter in diastole, PWTd is posterior wall thickness in diastole, LVIDs is LV internal diameter in systole, and PWTs is posterior wall thickness in systole. Biplane left atrial volumes were measured from apical 2-and 4-chamber views and indexed to the BSA.A comprehensive diastolic examination was completed with Doppler echocardiography: Diastolic dysfunction was graded as grade 1(impaired relaxat...