We read with interest the article by Kawachi, Tominaga, and Tokunaga' titled "Eleven-Year Follow up Study of Aortic or Aortic-Mitral Anulus-Enlarging Procedure by Manouguian's Technique" and appreciate their results. However, our own experience is different from theirs.Between June 1989 and September 1992, we have done aortic root enlargement by Manouguian's technique in 12 patients aged 20 to 51 years. One patient underwent aortic root enlargement as an emergency procedure for severe aortic regurgitation after balloon dilation of the aortic valve. In six patients, the anterior mitral leaflet was divided and a diamond-shaped Gelseal patch (gelatin-coated Dacron patch, Vascutek Inc., Inchinnan, Scotland) was sutured in the defect in the mitral leaflet. The edges of the Gelseal patch were buttressed by strips o~pericardium as well. In the remaining six patients, a pericardial patch was used to bridge the defect in the mitral leaflet. Whenever the roof of the left atrium was opened, it was closed by a patch of pericardium.A mechanical prosthetic valve, either St. Jude Medical (St. Jude Medical, Inc., St. Paul, Minn.) or Medtronic Hall (Medtronic, Inc., Minneapolis, Minn.), larger than the measured aortic root by either one or two sizes, was sewn into place with interrupted horizontal mattress sutures. None of the patients had any significant bleeding through the suture line. All the patients have been followed up for 6 months to 2 years and are doing well.Unlike Kawachi, Tominaga, and Tokunaga, we used only mechanical valves. In addition, none of the patients had either mitral regurgitation or hemolysis. The patient-prosthesis mismatch or small-sized prosthesis can produce complications such as a significant gradient, left ventricular hypertrophy, thrombosis, and hemolysis.l On the basis of our own experience and the report by Kawachi, Tominaga, and Tokunaga, we believe that aortic root enlargement can be done without much morbidity and the patient should be given the benefit of having a large prosthesis.