Surgical outcomes and strategy of hypertrophic obstructive cardiomyopathy

Extended septal myectomy versus alcohol septal ablation: clinical results at a national referral centre

OBJECTIVES

Extended septal myectomy and alcohol septal ablation are 2 invasive treatments for hypertrophic obstructive cardiomyopathy. Our goal was to compare which of these techniques achieved a higher reduction in gradients, improvement in New York Heart Association (NYHA) functional class and reduction in medical treatment.

METHODS

It is a single-centre observational and retrospective analysis. We used multivariable regression analyses to assess the association of ablation/myectomy with different outcomes. The odds ratio or coefficient along with the 95% confidence interval was estimated according to the group and adjusted for the corresponding preprocedural variables and EuroSCORE II.

RESULTS

A total of 78 patients underwent septal myectomy, and 25 patients underwent alcohol septal ablation. Basal and Valsalva gradients after myectomy were reduced to a higher degree in comparison to ablation: 21.0 mmHg [P < 0.001, 95% confidence interval -30.7; -11.3], and 34.3 mmHg (P < 0.001, -49.1; -19.5) respectively. Those patients who received a myectomy had a lower probability of having moderate mitral regurgitation (odds ratio = 0.18, P = 0.054). Patients after septal myectomy were more likely to be NYHA functional class I (80.4%), whereas patients after ablation were more likely to be NYHA functional class III (48%). Both groups continued with beta-blocker therapy, but disopyramide could be discontinued after the myectomy in more cases (20%-36% vs 59%-1.3%; P < 0.001), and there was a tendency to discontinue calcium channel blockers (48%-16% vs 15.4-3.8%; P = 0.054).

CONCLUSIONS

After adjustment using preprocedural gradients and EuroSCORE II, myectomy achieves greater reduction in left ventricular outflow tract gradients compared to septal ablation.

Treatment modalities in hypertrophic obstructive cardiomyopathy: surgical myectomy versus percutaneous septal ablation

BACKGROUND

The aim of this study was to compare the results of percutaneous septal myocardial ablation (PSMA) and surgical myectomy (SM) for decreasing the left ventricular outflow tract (LVOT) gradient, septal thickness, ventricular dimensions, and mitral regurgitation (MR) in patients with symptomatic hypertrophic obstructive cardiomyopathy.

METHODS

We treated 40 patients (mean age, 24.4 +/- 6.8 years; 34 male and 6 female patients) between June 2002 and April 2006. Twenty-four patients underwent SM, and 16 patients underwent PSMA. All patients were symptomatic despite maximal medical treatment and had an LVOT gradient higher than 65 mm Hg. Their echocardiographic data were recorded before and after the procedure and then compared. The patients were followed up postoperatively for a mean of 13 months.

RESULTS

There was no mortality in either group. One year after the procedure, the LVOT gradients for the 2 groups were not statistically different. During the follow-up, moderate MR was found in 4 patients (25%) in the ablation group and in 2 patients (8.3%) in the myectomy group. Exercise capacity and New York Heart Association class improved after PSMA, whereas postoperative MR severity and effort capacity were better in the surgical group.

CONCLUSION

The 2 approaches yielded similar results with regard to reducing the LVOT gradient. We conclude that SM is preferable to PSMA in cases with MR.