Inducción de infarto septal como alternativa terapéutica en la miocardiopatía hipertrófica obstructiva: nuevas observaciones a propósito de un caso

Effectiveness and safety beyond 10 years of percutaneous transluminal septal ablation in hypertrophic obstructive cardiomyopathy

INTRODUCTION AND OBJECTIVES

Percutaneous transluminal septal ablation is an alternative treatment in patients with hypertrophic obstructive cardiomyopathy. However, due to the relatively new introduction of this technique, there is no information on its very long term results (>10 years).

METHODS

The present study included consecutive patients treated in 5 centers between 1998 and 2003. We analyzed clinical, hemodynamic, and echocardiographic data at baseline and follow-up.

RESULTS

A total of 45 patients were included; there were 31 (69%) women, the mean age was 62.4 (14) years, and 39 patients (86.6%) showed functional class III or IV. Septal thickness was 21.8 (3.5) mm, the peak resting gradient on echocardiography was 77 (39) mmHg, and mitral regurgitation was at least moderate in 22 patients (48.8%). During hospitalization, permanent pacemaker implantation was required in 3 patients and ventricular perforation (by pacing lead) occurred in 1 patient, requiring surgery. After a follow-up of 12.3 years (11.0-13.5 years), 2 patients (4.4%) died from cardiac causes (heart failure and posttransplantation), 3 patients required an implantable cardioverter-defibrillator (1 for primary prevention and 2 due to sustained ventricular tachycardia after cardiac surgery), and 2 underwent cardiac surgery (due to endocarditis and mitral regurgitation). In the last clinical review, functional class was I-II in 39 patients (86.6%) (P<.0001), the peak resting gradient was 16 (23) mmHg (P<.0001), and mitral regurgitation was absent or mild in 34 patients (75.5%) (P<.03).

CONCLUSIONS

The results of this study suggest that septal ablation is safe and effective in the very long term. The procedure was not associated with a significant incidence of sudden death or symptomatic ventricular arrhythmias.

Does pacemaker implantation provide long-term benefits in severe obstructive hypertrophic cardiomyopathy?

INTRODUCTION AND OBJECTIVES

About 25% of patients with obstructive hypertrophic cardiomyopathy (HCM) remain symptomatic despite optimal medical treatment. Some may benefit from pacemaker implantation. The aim of this study was to determine the effect of pacemaker implantation on the left ventricular outflow tract (LVOT) gradient, the maximum thickness of the left ventricle, and functional capacity.

METHODS

In total, 72 patients with obstructive HCM and incapacitating symptoms underwent pacemaker implantation. Clinical examination, echocardiography (in 61 patients) and treadmill testing (in 34 patients) were performed before and after implantation.

RESULTS

Subjective functional capacity, as assessed using the New York Heart Association (NYHA) classification, improved in 43.1% of patients, but treadmill testing showed no change. There were significant reductions in subaortic gradient, from a median of 87.0 mmHg (interquartile range [IQR] 61.5-115.2 mmHg) to 30.0 mmHg (IQR 18.0-54.5 mmHg; P< .001), and maximum left ventricular thickness, from 22.1+/-4.5 mm to 19.8+/-3.6 mm (P=.001). Univariate analysis identified two factors associated with clinical improvement: female sex (odds ratio [OR]=3.43; P=.020) and functional class III/IV (OR=4.17; P=.009). On multivariate analysis, only functional class III/IV remained a significant predictor (OR=3.12; P=.048).

CONCLUSIONS

In patients with obstructive HCM and incapacitating symptoms, pacemaker implantation reduced the LVOT gradient and the maximum left ventricular thickness, but only 43.1% of patients experienced clinical improvement. The only factor predictive of improvement was advanced NYHA functional class.

[Occlusion of the first septal branch with microcoils in a patient with hypertrophic obstructive cardiomyopathy]

Nonsurgical septal reduction by induced septal infarction is one of the management options in the treatment of patients with hypertrophic obstructive cardiomyopathy. Good immediate and long-term clinical and hemodynamic results have been reported with this technique for occlusion of the first septal branch of the anterior descending coronary artery followed by ethanol infusion. This is the first report of a case in which nonsurgical septal reduction with microcoils has been attempted.