New Ways of Thinking About Senescent Bioprosthetic Heart Valve Therapy.

SEE PAGE 1735 I n patients requiring heart valve replacement, biologic valve substitutes have been implanted with increasing frequency over the past decade. According to the Society of Thoracic Surgeons (STS) database, bioprosthetic valve implants in the aortic position have increased from 43.6% in 1997 to 78.4% in 2006 (1). A similar trend has been seen for mitral valve replacement (2). The trend has largely been driven by an effort to free patients from reliance on valve-related anticoagulation despite recent evidence warning of a possible negative prognostic impact in individuals younger than 60 years of age (3). Further, notwithstanding improvements in hemodynamics and durability of third-generation devices, bioprosthetic valves are associated with an increased risk of structural valve deterioration, particularly in patients younger than 65 years of age (4–7). When bioprosthetic valves fail, reintervention has historically required repeat sternotomy; however, a significant proportion of these patients are at high risk of surgical reintervention. Transcatheter valve-invalve (VIV) implantation has emerged as a less invasive alternative to surgical valve replacement, offered within the confines of clinical trials in select high-risk patients. Transcatheter VIV replacement permits treatment of stenotic or regurgitant biological surgical valves by anchoring an expandable device within the dysfunctional valve. Initial global experience can be summarized as follows: 1) patients were typically elderly with high surgical risk; 2) early series had very