Septal myectomy significantly reduced mitral regurgitation in HOCM patients without independent mitral valve disease, resulting in absent or trivial MR in 80% of patients early postoperatively.
Cohort (n=104)
Does septal myectomy reduce mitral regurgitation severity in patients with hypertrophic obstructive cardiomyopathy?
Septal myectomy alone significantly reduces mitral regurgitation in HOCM patients without intrinsic mitral valve disease, as MR severity is directly related to the LVOT gradient.
p-value: p=<0.001
OBJECTIVES: This study examined: 1) the impact of myectomy on postoperative mitral regurgitation (MR) and 2) the association between the severity of MR and the left ventricular outflow tract (LVOT) gradient. BACKGROUND: For patients with hypertrophic obstructive cardiomyopathy (HOCM) and MR, controversy exists as to whether myectomy alone is sufficient in eliminating MR. Furthermore, the relationship between the degree of MR and the LVOT peak gradient has not been well defined. METHODS: We performed pre- and postoperative transthoracic as well as intraoperative transesophageal studies in 104 consecutive patients with HOCM undergoing septal myectomy. Left ventricular outflow tract gradient and the nature of MR were assessed. RESULTS: In the 93 patients without independent mitral valve disease, a relationship was observed between MR severity and the LVOT gradient. Left ventricular outflow tract gradient (mean +/- standard deviation) for trivial, mild, moderate and severe MR were: 23.2+/-19.1, 43.8+/-25.4, 70.1+/-21.0 and 104+/-21.0 mm Hg (p < 0.001). Early postoperative, MR was absent or trivial in 80%, mild in 19% and moderate in 1%. None of these patients required additional mitral valve surgery. For patients with independent mitral valve disease (n = 11), five required mitral valve surgery as well as myectomy. The remainder had significant reductions in the degree of MR with myectomy alone. CONCLUSIONS: For patients with HOCM and MR not due to independent mitral valve disease, myectomy significantly reduced the degree of MR, without requirement for additional mitral valve surgery. In these patients the severity of MR was directly related to the magnitude of the LVOT gradient.
Yu et al. (Fri,) conducted a cohort in Hypertrophic obstructive cardiomyopathy with mitral regurgitation (n=104). Septal myectomy was evaluated on Postoperative mitral regurgitation severity and relationship to LVOT gradient (p=<0.001). Septal myectomy significantly reduced mitral regurgitation in HOCM patients without independent mitral valve disease, resulting in absent or trivial MR in 80% of patients early postoperatively.