Bioprosthetic Aortic Valve Deterioration
Authors: Linda D. Gillam, Konstantinos P. Koulogiannis, Leo Marcoff
Journal: Circulation (2018)

Bioprosthetic Aortic Valve DeteriorationMore Common Than We Thought?Article, see p 971 T he limitations of using freedom from reoperation as an index of prosthetic valve deterioration are well recognized, because, even in the presence of severe prosthetic stenosis or regurgitation, patients may not undergo another procedure.Thus, other means of detecting valve deterioration, typically with noninvasive imaging, emerge as being essential to our understanding of the natural history of valve replacements.Although echocardiography has traditionally been used for this purpose, the current scrutiny on transcatheter aortic bioprostheses and the recognition that subclinical transcatheter and surgical aortic bioprosthetic valve thrombosis is more common than originally thought has led to an increasing role for cardiac computed tomography 1 in select patients.In recent years, there has been a trend for increased use of biological versus mechanical valves, fueled by aversion to systemic anticoagulation and the hope that, when these valves fail, a valve-in-valve catheter-based redo option will exist.In a report based on the 2011 National Inpatient Sample, the use of bioprosthetic aortic valve replacement (AVR) rose from 37.7% (sampling period 1998-2001) to 63.6% for 2007 to 2011 with significant increases in the age group 55 to 64 years. 2 Indeed, the 2017 American Heart Association/American College of Cardiology Focused Update of the 2014 American Heart Association /American College of Cardiology Guideline for the Management of Patients With Valvular Heart Disease lowered the age below which mechanical AVR is reasonable from 60 to 50 years, effectively lowering the age above which bioprosthetic AVR would be reasonable. 3With anticipated further growth in the use of bioprosthetic AVRs, it is important to optimize our understanding of the prevalence, causes, and outcomes of prosthetic valve degeneration with echocardiography providing excellent tools.In this issue, Salaun et al 4 expand our fund of knowledge in these areas by reporting echocardiographic and clinical observations on their single-site series of 1387 bioprosthetic AVRs, with 926 patients followed at least 5 years and 385 patients followed at least 10 years.It is important to note that they detected degeneration in 31% of patients, most of it subclinical.Within this subset of affected patients, degeneration occurred in 12% during the first 2 years (very early; 4% of all patients at risk), 30% between 2 and 5 years (early; 14% of all patients at risk), 37% between 5 and 10 years (midterm; 41% of all patients at risk), and 21% at >10 years (long-term; 39% of all patients at risk).Furthermore, they identify clinical variables that are associated with these changes.In so doing, they make a strong argument for more frequent echocardiographic surveillance than is currently recommended in the American College of Cardiology Guideline for the Management of Patients with Valvular Heart Disease, 3 and increase the attention that sonographers and reading physicians pay to assessing valve structure