Failing stentless aortic valves: redo aortic root replacement or valve in a valve?

Reoperation for failing stentless aortic valve replacement is a technically demanding procedure that has traditionally been tackled in one of two ways: either root replacement or the more conservative option of implanting a stented valve within the valve. We sought to determine the relative operative risks, follow-up status and medium to long-term survival of these two methods. We conducted a retrospective review of a single surgeon's experience of the two techniques over a 10-year period from 2000 to 2010. Excluding cases of active endocarditis, 110 patients were identified, of which 65 underwent 'valve-in-valve' procedures ('Group A') and 45 had redo root replacement ('Group B'). The most common bioprostheses reoperated were homografts (roots or subcoronary implants) and Toronto Stentless Porcine Valves. Aortic valve replacement alone was performed in 68% in Group A and 64% in Group B, with males comprising 75% of Group A and 82% of Group B. Average ages were 61.5 +/- 14.2 years and 61.9 +/- 12.1 years, respectively. Operative and cardiopulmonary bypass durations were significantly greater for redo root procedures and correspondingly, postoperative complications were more common. Thirty-day mortality after valve-in-valve replacement was 3%, and after redo root replacement it was 11%. Despite significantly higher transvalvular gradients in Group B, the symptomatic status was equally good at 2 months, 1 year and last follow-up. At an average interval of 5.1 +/- 2.7 years for Group A, survival was 83% vs 76% at 7.3 +/- 2.9 years for Group B. There have been two reinterventions in Group A and 3 in Group B. Only one valve-in-valve patient has developed a paraprosthetic leak. This retrospective review has confirmed our hypothesis that where both root diameter permits and satisfactory debridement can be performed, valve-in-valve replacement is the more conservative surgical strategy for stentless aortic valve replacement revision. Although transvalvular gradients on echocardiography are significantly higher with the introduction of a stented prosthesis, medium-term outcomes in terms of symptomatic status, late complications and reintervention rate were non-inferior. We await the medium-term results of transcatheter aortic valve implantation for the same indication with interest.