Hemodynamic outcomes of transcatheter aortic valve replacement and medical management in severe, inoperable aortic stenosis: a longitudinal echocardiographic study of cohort B of the PARTNER trial

Abstract

Background: Inoperable aortic stenosis may be treated with either transcatheter aortic valve replacement (TAVR) or medical management (MM) with or without balloon aortic valvuloplasty (BAV). The aim of this study was to compare the long-term echocardiographic findings among TAVR, MM, and BAV in patients with severe, inoperable aortic stenosis.

Methods: A total of 358 inoperable patients in the Placement of Aortic Transcatheter Valves trial were randomized to MM or TAVR. Echocardiograms obtained at baseline, 30 days, and 1, 2, and 3 years were analyzed by a central core laboratory.

Results: At baseline, TAVR and MM were similar, with more frequent Society of Thoracic Surgeons score > 10 (51.7% vs 65.0%, P = .03) and larger end-systolic volumes (54.5 ± 29.3 vs 69.1 ± 48.0 mL, P = .03) in MM. By 30 days after TAVR, mean aortic valve gradient had decreased (from 43.8 ± 14.7 to 10.0 ± 4.3 mm Hg, P < .001), ejection fraction had increased (from 53.2 ± 12.4% to 56.7 ± 10.0%, P < .001), and left ventricular (LV) mass index had decreased (from 144.7 ± 36.1 to 140.0 ± 37.9 gm/m(2), P < .05). After 1 year, aortic valve gradients and area were unchanged, while LV mass index had decreased by another 16 gm/m(2) (to 124 gm/m(2)). By 30 days after BAV, mean aortic valve gradient had decreased from 43.4 ± 15.0 to 31.9 ± 11.1 mm Hg, while ejection fraction and LV mass index were unchanged; gradient reverted to baseline at 1 year. No changes in gradients or mass were seen in MM patients.

Conclusions: TAVR results in immediate and sustained relief in pressure overload and improved LV systolic function, with continued regression of hypertrophy over 3 years. Poor clinical results with BAV are explained by the modest and transient reductions in pressure overload with BAV, which were not accompanied by improved LV function or remodeling. TAVR is the preferred treatment in eligible inoperable patients (ClinicalTrials.gov identifier NCT00530894).

Keywords: Aortic stenosis; Echocardiography; Transcatheter aortic valve replacement.