[Evaluation of surgical procedures based on the types of hypertrophied obstructive cardiomyopathy].

The surgical procedures were reviewed based on the types of hypertrophied obstructive cardiomyopathy in 20 patients. The patients were classified in three groups: (1) Asymmetric septal hypertrophy (ASH), (2) Atypical or diffuse concentric hypertrophy (DIF), (3) Mid ventricular obstructive hypertrophy (MID). Among 11 patients with ASH, the ventricular septal myotomy (My) or the myotomy-myectomy (Mye) were performed in 9 patients and MVR was performed in 2 patients. Among 6 patients with DIF, My or Mye were performed in 4 and MVR was performed in 2. All three patients with MID were treated with MVR. The intraventricular systolic pressure gradient greater than 40 mmHg was still existent postoperatively in one ASH patient on whom Mye was performed and in 3 DIF patients on whom My or Mye were performed. The four patients had III degree mitral regurgitation preoperatively and were successfully treated. The postoperative NYHA functional class became II or less in all patients. For ASH, the My was effective in 9 patients except one earlier patient. For DIF, further consideration of surgical procedure might be required. For MID, a MVR is recommended.