Surgical treatment of mitral valve disease: pathologic findings and atrial dysrhythmia

One hundred fifty patients underwent surgery for mitral valve disease between January 1974 and May 1981. There were 98 female and 52 male patients with a mean age of 57 years (+/- 18.6). One hundred forty-six patients were in New York Heart Association functional class III or IV. Pathologic diagnoses included 67% rheumatic (55 calcified), 27% degenerative and fibrotic, 3.3% prosthetic valve malfunctions, and 2.6% acute papillary muscle dysfunction. Atrial biopsy material was normal in 72% (37/51) and Aschoff's bodies were present in 2% (1/51). Preoperative cardiac rhythm was regular sinus in 40%, atrial fibrillation in 59%, and pacemaker-induced in 1%. Valve replacement was performed in 119 patients, commissurotomy in 26, and annuloplasty in five. Left atrial thrombus was removed from 21 patients. Hospital mortality was 10%. The 135 survivors have been followed up for an average of 30.4 months. Of patients who were in regular sinus rhythm preoperatively, 90.7% maintained it postoperatively, and 9.3% converted to atrial fibrillation. Of patients in atrial fibrillation preoperatively, 33.8% converted to regular sinus rhythm postoperatively and 66.2% remained in atrial fibrillation. These data indicate that rheumatic mitral valve disease is still the most common finding in patients coming to surgery, followed by degenerative and fibrotic mitral valve disease. Acute papillary muscle dysfunction is uncommon. The chance of preserving preoperative regular sinus rhythm postoperatively is excellent (90.7%), and a 33% conversion rate of preoperative atrial fibrillation to postoperative regular sinus rhythm is encouraging.