As the indications for transcatheter aortic valve replacement (TAVR) have expanded to include younger and less ill patients and the number of patients referred for aortic valve procedures has increased, clinicians face new challenges associated with these patients’ longer-term care. Intermediate and low-risk patients may well require a second or third intervention.[i]
Planning for a lifetime of care starts with selection of the first procedure and the appropriate valve as well as evaluation of the best options in a future valve-in-valve procedure is needed.[ii]
Surgical aortic valve replacement (SAVR) is recommended for patients with life expectancy of 20 or more years, in part because there is a paucity of long-term data on the durability of TAVR valves. The data available on TAVR valve durability, however, is encouraging.
At eight years of follow up, the NOTION trial showed that TAVR valves had significantly lower rates of structural valve deterioration, 13.9%, compared to SAVR at 28.3%, and similar rates of bioprosthetic valve failure, 8.7% and 10.5% for TAVR and SAVR, respectively. An analysis using discrete event simulation demonstrated that durability of TAVR valves would need to be 70% less than that of valves used in SAVR to change life expectancy.[iii]
Further, a desire to avoid commitment to life-long anticoagulation medication and associated bleeding risks required by mechanical valves combined with improved results and durability of bioprosthetic valves has led to preferential use of bioprosthetic valves in SAVR for 20 years.
Bioprosthetic valves used in SAVR are estimated to last between 10 and 15 years before requiring replacement.[iv] Twenty percent of individuals who have SAVR with a bioprosthetic valve require a second valve within 10 years.[v] Consequently, patients who receive their first valve replacement at 60 or 65 will likely need another before they turn 80, regardless of the procedure type used initially.
Valve-in-valve posts 90% success rate
Beyond durability, other issues to consider when weighing the possible need for future interventions include coronary obstruction and reintervention. SAVR valves with leaflets that extend beyond the device frame increase the risk of coronary occlusion and others may increase risk associated with subsequent procedures.[vi]
For patients with failed surgically implanted replacement valves, redo surgery has been the standard of care. Recent data, however, indicates that transcatheter aortic valve-in-valve implantation may be a better option, with its procedural success rate of more than 90%.[vii]
Anatomical features such a narrow sinus of Valsalva, low coronary ostial height and tricuspid vs bicuspid valves should be considered in replacement valve selection to ensure coronary access after valve replacement. In addition, device characteristics such as short stent-frame height and procedural factors such as implantation depth may also factor into concerns about future coronary access.[viii]
