Influence of Septal Thickness on the Clinical Outcome After Alcohol Septal Alation in Hypertrophic Cardiomyopathy.

BACKGROUND: We assessed the influence of interventricular septal thickness (IVSd) on the clinical outcome and survival after alcohol septal ablation (ASA) in patient with hypertrophic cardiomyopathy. METHODS AND RESULTS: We analyzed 531 patients with hypertrophic cardiomyopathy (age: 56±14 years, men 55%) treated with ASA. Survival status was obtained 7.9±4.0 years after ASA. Baseline IVSd was inversely associated with survival (hazard ratio [HR] for 1 mm increment, 1.13; confidence interval, 1.05-1.21; P<0.001) after adjustment for age, sex, body mass index, and ASA-performing center. Compared with patients with baseline IVSd <20 mm, patients with baseline IVSd ≥25 mm had reduced survival (HR, 5.0; CI, 2.1-12), whereas patients with baseline IVSd 20 to 24 mm had similar survival (HR, 1.4; CI, 0.7-2.8). Baseline IVSd was not correlated with New York Heart Association class, Canadian Cardiology Society class, or syncope. Clinical outcome was assessed 0.6±0.6 years after ASA. IVSd was not related to left ventricular outflow tract gradient reduction at rest (P=0.883) or during Valsalva maneuver (P=0.885). The proportion of patients in New York Heart Association class 3 to 4 was reduced from 86% to 10%; in Canadian Cardiology Society class 3 to 4 from 26% to 2%; and with syncope from 25% to 2%. There were no correlations between baseline IVSd and New York Heart Association class (P=0.067), Canadian Cardiology Society class (P=0.106), or syncope (P=0.426) after ASA. CONCLUSIONS: ASA had equal effects on left ventricular outflow tract gradients and symptoms throughout the spectrum of septal hypertrophy. Severe septal hypertrophy before ASA remained a marker of reduced survival after ASA with a 5-fold increased risk of all-cause mortality in patients with baseline IVSd >25 mm compared with patients with baseline IVSd <20 mm.

Long-term outcome of percutaneous transluminal septal myocardial ablation in hypertrophic obstructive cardiomyopathy: a Scandinavian multicenter study.

BACKGROUND: Single-center reports on percutaneous transluminal septal myocardial ablation (PTSMA) in patients with hypertrophic obstructive cardiomyopathy have shown considerable differences in outcome. METHODS AND RESULTS: We report the long-term outcome of 313 PTSMA procedures performed in 279 patients with hypertrophic obstructive cardiomyopathy aged 59±14 years from 1999 to 2010 in 4 Scandinavian centers. Sixty-nine percent of patients had ≥1 comorbidity at baseline. The median (interquartile range) of left ventricular outflow tract gradient at rest was reduced from 58 mm Hg (34 to 89 mm Hg) at baseline to 12 mm Hg (8 to 24 mm Hg) at 1-year (P<0.001) and during Valsalva maneuver from 93 mm Hg (70 to 140 mm Hg) to 21 mm Hg (11 to 42 mm Hg) (P<0.001). The proportion of patients with syncope was reduced from 18% to 2% (P<0.001), and the proportion in New York Heart Association class III/IV was reduced from 94% to 21% (P<0.001). All treatment effects remained stable during the follow-up. New York Heart Association class III/IV at the most recent follow-up (2.9±2.6 years) was associated with diabetes mellitus (P=0.03), chronic obstructive pulmonary disease (P=0.02), and valve disease unrelated to hypertrophic cardiomyopathy (P<0.01). In-hospital mortality was 0.3%. The 1-, 5- and 10-year survival rates were 97%, 87%, and 67%, respectively (P=0.06 versus an age- and sex-matched background population) in all patients and 99%, 94%, and 88%, respectively (P=0.12) in patients aged <60 years (48±9 years, n=141). Age (hazard ratio, 1.07; 95% CI, 1.03 to 1.1) was the only predictor of survival. CONCLUSIONS: In this multicenter study, the in-hospital mortality after PTSMA was low despite considerable comorbidities. The hemodynamic and symptomatic effects were sustained long term. The long-term symptomatic outcome was associated with baseline comorbidities. The 10-year survival rate was comparable to that in an age- and sex-matched background population, and age was the only predictor of survival.