Long-term follow-up of direct current cardioversion after cardiac surgery with special reference to quinidine.

The results of the long-term follow-up of 119 patients who had DC cardioversion performed are described. All patients had had corrective cardiac surgery for chronic rheumatic valvar heart disease. The poor prognosis for maintenance of sinus rhythm in this type of patient is emphasized. Of the total patients, 83 per cent were converted to sinus rhythm, but relapses were common in those who had atrial fibrillation before operation. Only 40 per cent of such patients maintained sinus rhythm for 2 months, 15 per cent for 1 year, and 9 per cent for 2 years.By contrast, when atrial fibrillation occurred for the first time in the post-operative period, 82 per cent maintained sinus rhythm for 2 years after conversion.Post-operative DC cardioversion is in general not recommended for patients with rheumatic heart disease and atrial fibrillation unless atrial fibrillation occurs for the first time in the post-operative period. A controlled trial of prophylactic quinidine is reported and shows no significant increase in the number of patients remaining in sinus rhythm as compared with a control group not receiving quinidine.