The INTACT bioprosthesis--early results.

Abstract

The INTACT (previously Xenotech) valve incorporates three major departures from previously available bioprostheses. The following innovations are aimed at reducing calcification and improving durability: (1) the stent has a high profile configuration and the sinuses are deeply excavated. This should maintain normal coaption of the leaflets and prevent cusp abrasion; (2) stress-free fixation preserves the structural characteristics of the leaflets; (3) the valve is treated with toluidine blue, which occupies the calcium binding sites. During a 36-month period 185 valves were implanted in 167 patients. The procedure used most often was isolated mitral valve replacement. Twenty-six patients were under the age of 20. There were 8 hospital deaths (5% mortality) and 12 late deaths. Two of the hospital deaths were the result of ventricular perforation, and it is believed that the high profile of the stent contributed. In the group aged less than 20 years, there have been three episodes of valve calcification giving a 3-year actuarial rate for calcification of 22%. In the adult group, there have been no valve failures, and postoperative catheterization studies in this group demonstrated satisfactory hemodynamics.