Thorac cardiovasc Surg
DOI: 10.1055/s-0035-1570748
Original Cardiovascular
Georg Thieme Verlag KG Stuttgart · New York

Surgery for Left Ventricular Outflow Tract Obstruction with a Relatively Thin Interventricular Septum

Yasushige Shingu1, Hiroshi Sugiki2, Tomonori Ooka3, Hiroki Kato4, Satoru Wakasa3, Tsuyoshi Tachibana3, Yoshiro Matsui3
  • 1Department of Cardiovascular and Thoracic Surgery, Hokkaido University Hospital, Sapporo, Japan
  • 2Department of Cardiovascular Surgery, Hokko Memorial Hospital, Sapporo, Japan
  • 3Department of Cardiovascular and Thoracic Surgery, Hokkaido University Graduate School of Medicine, Sapporo, Japan
  • 4Emergency and Critical Care Center, Hokkaido University Hospital, Sapporo, Japan
Further Information

Publication History

18 August 2015

24 November 2015

Publication Date:
12 January 2016 (eFirst)

Abstract

Background To examine the results of myectomy and mitral valve surgery for systolic anterior motion (SAM) of the mitral valve and left ventricular outflow tract obstruction (LVOTO) with a relatively thin interventricular septum.

Methods The subjects were 12 patients with SAM and LVOTO. Eight had hypertrophic obstructive cardiomyopathy (HOCM) with a mean interventricular septal thickness of 16 mm. Three had sigmoid septum and one had an unknown etiology. For HOCM, isolated extended myectomy was performed when mitral regurgitation was mild (n = 1) and extended myectomy plus mitral valve surgery was performed when mitral regurgitation was more than mild (n = 4) or primary valve etiologies existed (n = 3). Myectomy was performed for the three cases with sigmoid septum. Myectomy plus height reduction of the posterior mitral leaflet was performed for the one case with the unknown etiology of SAM.

Results In the patients with HOCM, the maximum LVOT pressure gradient significantly decreased from 140 ± 18 to 16 ± 6 and 3 ± 3 mm Hg, while mitral regurgitation significantly decreased from 2.3 ± 0.5 to 0.5 ± 0.3 and 0.4 ± 0.2 at pre-op, early post-op, and last follow-up (3 ± 1 years), respectively. In the other etiologies, the maximum LVOT pressure gradient changed from 56 ± 15 to 25 ± 15 and 5 ± 4 mm Hg; mitral regurgitation changed from 2.0 ± 0.6 to 1.3 ± 0.3 and 1.3 ± 0.8, at pre-op, early post-op, and the last follow-up (3 ± 2 years), respectively.

Conclusion Myectomy with mitral valve surgery is an option for SAM and LVOTO in patients with a relatively thin interventricular septum.