Robotic Trans-Mitral Septal Myectomy and Papillary muscle reorientation
for HOCM combined with or without Mitral valve repair: Technical aspects
– How we do it
Abstract
Hypertrophic obstructive cardiomyopathy (HOCM) is one of the more common
genetic disorders. The pathophysiology and natural history of the
disease have been well studied. Left ventricular outflow tract (LVOT)
obstruction and systolic anterior motion (SAM) of the anterior mitral
leaflet can result in sudden cardiac death, progressive heart failure
and arrythmias. Surgical septal myectomy for HOCM is the standard of
care and is routinely performed through a median sternotomy. Septal
myectomy has also been performed using the trans-atrial, trans-mitral
approach either directly or with robotic assistance. In cases with
severe LVOT obstruction in the setting of only mild to moderate proximal
septal hypertrophy, intrinsic problems with the mitral valve contribute.
Typically, these are hyper-mobile papillary muscles and or excessive
height of the anterior mitral leaflet. Combining septal myectomy with
reorientation of hyper-mobile anteriorly positioned papillary muscles
has shown to prevent SAM and thereby additionally decrease the
sub-valvular aortic outflow obstruction. Our extensive experience in
both septal myectomy and robotic mitral valve repair has given us a
different perspective in approaching the primary mitral regurgitation in
HOCM patients where a combined septal myectomy, papillary muscle
reorientation and complex mitral valve repair has been safely performed
using the less invasive robotic-assisted approach. Our objective here is
to discuss the technical aspects of the procedure.