BACKGROUND Massive calcification of the atrial walls ("porcelain atrium") is a rare condition that usually has been reported as an incidental radiologic findings. METHODS Between January 1988 and June 1993, 971 patients underwent valvular operation at our institution; 21 patients showed extensive calcification of the left atrium. In 8 patients the calcification was massive, involving almost all the atrial surface. The diagnoses were established by radiology and were confirmed at operation. The mean age of these patients (4 men, 4 women) was 55 +/- 9.6 years. All had rheumatic valve disease, were on atrial fibrillation, and had undergone at least one operation previously. Pulmonary artery pressure was severely increased, even up to systemic levels, in all patients except 1. Total endoatriectomy of the left atrium and mitral valve replacement were performed. No patient was lost during the follow-up. RESULTS Hospital mortality rate was 12.5% (1 patient) and 2 patients died in the late postoperative period. None of these deaths are attributable to the surgical procedure. CONCLUSIONS In toto endoatriectomy of a massively calcified atrium is an easy to perform technique that helps to replace the mitral valve and close the atrial wall.