Primary tissue failure of the Freestyle stentless aortic root bioprosthesis.

We present a case of early tissue failure of the Medtronic Freestyle stentless bioprosthesis used in the aortic position which led to reoperation 27 months after implantation. Almost one half of the left coronary cusp of the prosthetic valve had torn away along the annulus. The tear started from the left-non coronary commissure and reached the midpoint of the base of the left coronary cusp. The prosthetic valve was easily excised and replaced with a new mechanical valve. There was no sign of calcification or vegetation in the excised valve. The cause of the valve dysfunction was thought to be primary tissue failure. Long-term function of the Freestyle stentless valve should be carefully followed up.