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The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation
Published on: February 28, 2012
Long-term clinical and hemodynamic performance of the Hancock II versus the Perimount aortic bioprostheses
Vincent Chan1, Alexander Kulik, Anthony Tran
1Division of Cardiac Surgery, University of Ottawa, Ottawa, Ontario, Canada.
Background:
The Medtronic Hancock II and the Carpentier-Edwards Perimount are among the world's most commonly used aortic bioprostheses. However, a direct comparison of their clinical performance is lacking. To minimize biases inherent to between-center comparisons, we examined these prostheses within a large, contemporary, single-center cohort.
Methods And Results:
Between 1990 and 2007, 1659 patients (mean age, 73.1±9.3 years) underwent aortic valve replacement with either the Hancock II (N=1021) or the Perimount (N=638). Patients were prospectively followed-up with serial clinic visits and echocardiograms for up to 16 years (mean, 5.0±3.3 years). There was no significant difference in aortic root size preoperatively (P=0.7). Aortic root enlargement was more commonly performed with the Perimount (P<0.001), and the manufacturer valve size of the implanted prosthesis was larger with the Hancock II (P<0.001). Postoperatively, peak and mean transprosthesis gradients were higher for the Hancock II (32.7±0.7 and 16.0±0.3 mm Hg, respectively) than for the Perimount (24.9±0.7 and 13.4±0.4 mm Hg, respectively; P<0.001). However, no difference in left ventricular mass regression was observed at late follow-up (P=0.9). Unadjusted 10-year survival was 59.4%±2.4% for the Hancock II and 70.2%±3.8% for the Perimount (P=0.07). Multivariable predictors of survival did not include prosthesis type (P=0.2).
Conclusions:
For the same manufacturer valve size, the Perimount is larger, which may warrant enlarging the aortic root more often, and it is associated with better hemodynamics than the Hancock II. These differences do not impact survival or left ventricular mass regression, and the long-term clinical performances of the Hancock II and Perimount bioprostheses are equivalent.
