30 YEARS EXPERIENCE WITH HEART-VALVE SURGERY - ISOLATED MITRAL-VALVE REPLACEMENT

Background: Thirty years have elapsed since the commencement of open-h eart surgery in South Australia. A retrospective study was performed t o evaluate mortality and complication rates and to identify factors as sociated with poor outcomes in all patients who underwent prosthetic m itral valve replacement during this period. Methods: Questionnaires an d personal contact have been used to generate a combined database of p re-operative and postoperative information and long-term follow-up on 938 patients who underwent isolated prosthetic mitral valve replacemen t at the Cardio-Thoracic Surgical Unit of the Royal Adelaide Hospital between 1963 and 1993. Results: Complete survival follow-up data were obtained for 92% (865) Of the patients. The Starr-Edwards valve was us ed in 95% (891) of the patients, a Bjork-Shiley prosthesis in 2.5% (23 ) of the patients, and only 24(2.5%) other valves were inserted. The h ospital mortality rate for the 30-year period was 4.7%. The mean age o f the patients who underwent surgery was greater in each of the three successive decades. A long term survival advantage was observed for pa tients with mitral stenosis, however, survival was significantly short er for patients with higher New York Heart Association (NYHA) function al classifications and for patients in pre-operative atrial fibrillati on. Pre-operative dyspnoea was significantly improved following mitral valve replacement. The rates of postoperative haemorrhagic and emboli c complications were low by comparison with other published series. Co nclusion: Mitral valve recipients do not regain a normalized life expe ctancy, but risk factors that determine long-term survival can be iden tified pre-operatively to aid appropriate patient selection.