Author + information
- Received August 4, 1988
- Revision received February 16, 1989
- Accepted March 8, 1989
- Published online August 1, 1989.
- Kanji Kawachi, MD∗,
- Soichiro Kitamura, MD, FACC,
- Ryuichi Morita, MD,
- Tsutomu Nishii, MD,
- Toshio Seki, MD,
- Shigeki Taniguchi, MD and
- Kiyoshi Inoue, MD
- ↵∗Address for reprints: Kanji Kawachi, MD, Department of Surgery, Division of Thoracic and Cardiovascular Surgery, Nara Medical College, 840 Shijo-cho, Kashihara, Nara, Japan 634.
Between December 1981 and June 1987, 71 patients underwent aortic valve replacement with a Bicer monostrut tilting disc prosthesis. Clinical results and in vivo function of the artificial valve were assessed. The average age of the 71 patients at the time of operation was 51.3 ± 11.5 years. The hospital mortality rate was 2.8% (two patients) and there were no further deaths during a mean (±SD) follow-up period of 2.4 ± 1.6 years (range 1 month to 5.5 years) after surgery. There was also no occurrence of thromboembolism or valve dysfunction.
Function of the Bicer valve prosthesis was assessed in 17 patients: 5 with a 21 mm valve, 7 with a 23 mm valve and 5 with a 25 mm valve. Examination was performed on average 10.3 ± 8.1 months after surgery. Valve function was examined at rest and during exercise performed with a bicycle ergometer. Pressure gradients at rest were low: 21 mm valve = 8 mm Hg, 23 mm valve = 3 mm Hg and 25 mm valve = 2 mm Hg; the gradients during exercise were 11, 8 and 8 mm Hg, respectively. The valves had the following effective orifice area at rest: 21 mm valve = 1.54 cm', 23 mm valve = 4.20 cm2 and 25 mm valve = 3.76 cm2; during exercise, the respective areas were 1.57, 3.48 and 3.01 cm2. These valves are deemed to be sufficiently wide for effective valve function. Aortographic observation indicated mild regurgitation that was within reasonable limits and posed no problem. On the basis of these results, particularly in light of its low resistance, the Bicer valve prosthesis is considered an excellent prosthesis for use in the aortic position.
- Received August 4, 1988.
- Revision received February 16, 1989.
- Accepted March 8, 1989.