Serial changes of hemodynamic performance with Medtronic Hall valve in aortic position

Abstract

Background: The aim of this study was to evaluate the long-term hemodynamic performance of the Medtronic Hall valve by analyzing serial changes in echocardiographic outcomes in aortic position.

Methods: One hundred seventeen patients who underwent aortic valve replacement (AVR) using the Medtronic Hall valve between August 1997 and January 2004 were retrospectively studied. Fifty-five patients underwent isolated AVR (AVR group), and 62 patients underwent AVR and mitral valve replacement (double valve replacement group). Mean age was 51.2 ± 10.4 years (range, 26 to 67 years), and mean follow-up duration was 93.7 ± 25.6 months (913.6 patient-years; range, 17 to 140 months). Serial echocardiographic data were analyzed.

Results: Overall mortality was 12.8% (15 of 117), but no early mortality occurred. A greater than 15 mm Hg increment of aortic transprosthetic mean pressure gradient at last follow-up occurred in 13 patients (11.1%). Redo AVR was performed in 7 patients, 6 of whom had subaortic pannus ingrowths. Group cumulative survival rates at 10 years were similar (90.4%, AVR group versus 88.4%, double valve replacement group; p = 0.580), but the AVR group showed better adverse cardiac event-free survival at 10 years (80.1% versus 53.8%; p = 0.025). Multivariate analysis showed that double valve replacement and a small-sized valve (20 mm) significantly predicted the increment of aortic transprosthetic mean pressure gradient at last follow up greater than 15 mm Hg (p = 0.013; odds ratio, 13.9; p = 0.019; odds ratio, 4.2, respectively).

Conclusions: The transprosthetic mean pressure gradient of the Medtronic Hall valve in the aortic position frequently increased as a function of time, and this increase was more common in patients who had undergone double valve replacement, especially in those implanted with a small valve.