Late postoperative anatomic observations after insertion of Hufnagel caged-ball prostheses in descending thoracic aorta.

Clinical and necropsy observations are described in two patients who died 11 and 13 years, respectively, after implantation of Hufnagel prostheses (the first ever used successfully in humans to treat cardiac valve disease) in descending thoracic aorta. Despite the long implantation periods, there was no evidence of prosthetic degeneration or thrombosis or intravascular hemolysis. Although approximately 4000 Hufnagel descending aortic prostheses were distributed by the manufacturer for human use, data in only 55 patients in whom these prostheses were inserted were found in previous publications, and 26 of them had died. Of the 13 late deaths previously reported, no evidence of prosthetic degeneration or thrombosis was described in the three patients surviving greater than 3 years (8, 10, 12.5 years, respectively). Since neither our patients nor any of the other three reported long-term survivors had prosthetic-related complications and since the dangers of excising the descending aortic prosthesis are considerable, it appears most reasonable, as a rule, not to remove the descending aortic prosthesis at any time in these patients if aortic valve replacement is subsequently performed.