Septal myectomy, papillary muscle resection, and mitral valve replacement for hypertrophic obstructive cardiomyopathy: a case report.

We report a case of hypertrophic obstructive cardiomyopathy (HOCM) successfully treated with septal myectomy and mitral valve replacement (MVR) combined with a resection of the hypertrophic papillary muscles. The patient, a 74-year-old woman, first underwent the conventional septal myectomy through aortotomy. The papillary muscles revealed a marked hypertrophy, but extended myectomy and precise resection of the hypertrophic papillary muscles were thought to be difficult through the aortotomy. Through the right-sided left atriotomy, MVR and resection of the papillary muscles were additionally performed. The patient was smoothly weaned from the cardiopulmonary bypass, and the postoperative course was uneventful. The outflow pressure gradient was relieved to 0 mm Hg, from 94. The mean pulmonary artery pressure was reduced to 27 mm Hg, from 42. The patient has been doing well in the New York Heart Association (NYHA) functional class between I and II during 45 months of follow-up, without complications related to the use of a prosthetic valve. Septal myectomy is the procedure of choice in the surgical treatment of HOCM for most cases, but some may require additional mitral valve procedures. In patients with marked hypertrophic papillary muscles, MVR and resection of the muscles may be an option of treatment to ensure a relief of the outflow obstruction and to abolish systolic anterior movement in units with limited experience.