Hypertrophic Obstructive Cardiomyopathy: Septal Myectomy and Transaortic Mitral Valve Repair

In patients with hypertrophic obstructive cardiomyopathy, sparing the mitral valve can be a great challenge for the cardiac surgeon. In fact, the anatomy of this disease is greatly inconstant with the left ventricular outflow tract (LVOT) obstruction resulting from septal hypertrophy and from several abnormalities of the mitral valve apparatus that are variably expressed in the diverse patients [1-2].

In the subset of patients with a relatively thin interventricular septum, mitral valve abnormalities—of which the anterior displacement of the anterolateral papillary muscle and the presence of shorter secondary chords to the anterior mitral leaflet (AML) often are the most relevant ones—become predominant in the origin of the typical systolic anterior motion (SAM). In such patients, septal myectomy is rarely sufficient to resolve the LVOT obstruction and a mitral valve repair often becomes necessary. In this video, the authors detail the approach utilized at their institution in Ancona, Italy. It combines a shallow septal myectomy with a transaortic mitral valve repair, including papillary muscle mobilization and AML secondary chordal cutting. In the last two years, the authors have used this technique in 18 patients with satisfactory outcomes. In all patients but one, it was possible to spare the mitral valve and resolve the LVOT obstruction.

References

1. Holst KA, Hanson KT, Ommen SR, Nishimura RA, Habermann EB, Schaff HV. Septal myectomy in hypertrophic cardiomyopathy: national outcomes of concomitant mitral surgery. Mayo Clin Proc. 2019;94(1):66-73.
2. Wei LM, Thibault DP, Rankin JS, et al. Contemporary surgical management of hypertrophic cardiomyopathy in the United States. Ann Thorac Surg. 2019;107(2)460-466.