Restenosis of the mitral valve.

It is suggested that restenosis is inevitable after mitral valvotomy and that only the time taken for it to occur is variable. The major factor affecting the lapse of time between operations is the extent of the original valvotomy. Calification of the valve is less important, and coincident mitral incompetence and the age of the patient have almost no influence on the time taken for restenosis to develop. A study has been made of 281 second closed valvotomies and 53 third ones. The operative mortality for second closed valvotomy was 6.7% and for third closed valvotomy 4%. Late emboli were rare. The average follow-up period after second valvotomies was 12.8 years: the condition of 29% of these patients was still satisfactory; 21% had had third valvotomies. At 5 years the condition of 53% was satisfactory. The average length of follow-up after third valvotomy was 6.4 years: the condition of 47% of patients was still satisfactory and the results were similar to those after second valvotomy. It is concluded that closed valvotomy remains the operation of choice when restenosis has occurred.