Characteristics and Outcomes of Patients With Severe Bioprosthetic Aortic Valve Stenosis Undergoing Redo Surgical Aortic Valve Replacement

Abstract

Background: With improved event-free survival of patients undergoing primary bioprosthetic aortic valve replacement (AVR), reoperation to relieve severe prosthetic aortic stenosis (PAS) is increasing. We sought to (1) identify of the characteristics of patients with severe bioprosthetic PAS undergoing redo AVR, and (2) assess the outcomes of these patients, along with factors associated with adverse outcomes.

Methods and results: We studied 276 patients with severe bioprosthetic PAS (64±16 years, 58% men) who underwent redo-AVR between 2000 and 2012 (excluding mechanical PAS, severe other valve disease, and transcatheter AVR). Society of Thoracic Surgeons score was calculated. Severe PAS was defined as AV area <0.8 cm(2), mean AV gradient ≥40 mm Hg, or dimensionless index <0.25. A composite outcome of death and congestive heart failure admission was recorded. Mean Society of Thoracic Surgeons score and mean AV gradients were 8±8 and 53±17 mm Hg, whereas 28% had >II+ aortic regurgitation. Only 39% had an isolated redo AVR, the rest were combination surgeries (coronary bypass and/or aortic surgeries). At 4.2±3 years, 64 (23%) patients met the composite end point (48 deaths and 19 congestive heart failure admissions, 2.5% 30-day deaths). On multivariable Cox survival analysis, higher Society of Thoracic Surgeons score (hazard ratio, 1.35), higher grades of aortic regurgitation (hazard ratio, 1.29), and higher right ventricular systolic pressure (hazard ratio, 1.3) were associated with worse longer-term outcomes (all P<0.01).

Conclusions: At an experienced center, in patients with severe bioprosthetic PAS undergoing redo AVR, the majority undergo combination surgeries but have excellent outcomes.

Keywords: aortic valve replacement and outcomes; bioprosthetic aortic stenosis.