Myectomy delivers excellent long-term outcomes in obstructive HCM

Cutting thickened or retracted secondary chordae of the anterior mitral leaflet related to septal myectomy demonstrates positive long-term clinical and haemodynamic results in patients with hypertrophic cardiomyopathy (HCM), a study has shown.

“We previously reported the short-term results of cutting anterior mitral leaflet secondary chordae in combination with septal myectomy in patients with obstructive HCM,” the authors said.

“This operative approach has shown excellent results in several short-term studies from our and other centres. However, no data are currently available regarding the long-term outcome of this novel surgical procedure,” they added.

In the current study, the authors examined long-term results of myectomy associated with chordal cutting in 350 consecutive patients with obstructive HCM who underwent the procedure. The median follow-up was 5.6 years.

Overall survival at 6 years was 96 percent, including two in-hospital deaths (surgical mortality 0.6 percent), which was similar to that of the general population matched for age and sex (p=0.331).

Some 344 patients (99 percent) had available follow-up data. Of these, 271 (79 percent) were asymptomatic in NYHA functional class I, 65 (19 percent) were in NYHA functional class II, and eight (2 percent) were in NYHA functional class III.

Fourteen deaths occurred during follow-up, of which six were not related to HCM. At the most recent echocardiographic assessment, at least 95 percent of patients showed no residual left ventricular outflow gradient, clinically significant mitral regurgitation, or impaired systolic function.

“These findings may further increase the number of myectomy referral centres and the availability of the surgical option for severely symptomatic HCM patients unresponsive to medical treatment,” the authors said.