Transcatheter aortic valve replacements from Edwards Lifesciences and Medtronic are now being used for patients, who have already undergone surgery, but whose bioprosthetic valves have failed.

Though, patients and doctors prefer bioprosthetic valves instead of mechanical valves, the main disadvantage of bioprosthetic valves is that they might deteriorate, which means more patients and doctors will be faced with the quandary of how best to treat degenerated valves.

While, surgery is considered the best option, many patients are too old and weak to be considered for surgical operation, therefore transcatheter aortic valve implantation (TAVI) has been suggested for use in this situation, however the benefits and risks have not been well defined.

Currently, a new research in JAMA provides useful information and details on 459 patients with failed bioprosthetic valves, who underwent transcatheter aortic valve implantation with either the Medtronic Corevalve device or Edwards Sapien device.

According to the researchers in VIVID (Valve-in-Valve International Data) Registry, the death rate was 7.6 percent at 1 month and 16.8 percent at 1 year.

Moreover, a total of 39.5 percent of valve failures were due to stenosis, 30.3 percent due to regurgitation, and 30.3 percent due to a combination of the two.

It was noticed that survival rate was lowest in stenosis group and in patients with small valves when compared with patients with intermediate-size or big valves.