Survival after transcoronary ablation of septal hypertrophy in hypertrophic obstructive cardiomyopathy (TASH): a 10 year experience.

BACKGROUND: Catheter-based treatment of patients with hypertrophic obstructive cardiomyopathy (HOCM) by alcohol ablation (transcoronary ablation of septal hypertrophy, TASH) leads to symptomatic and haemodynamic improvement. However, little is known regarding the survival and its evolution since the introduction of the method in 1995. Theoretically, the method may be harmful, because widening of the obstructed left ventricular outflow tract is achieved by a septal infarction and subsequently by a potentially arrhythmogenic scar. OBJECTIVE: This study sought to determine the impact of TASH on the survival of all patients with HOCM treated in our institution between 1995 and 2005. METHODS: Survival was assessed from the early beginning in each of 644 consecutive patients to April 2005. Group A comprises a first series of 329 patients who were treated in a dose finding strategy with decreasing amounts of ethanol until December 2001, on average, from 2.9 ml to 0.93 ml/patient. The survival of this group was analysed using Kaplan-Meier estimates, multivariate Cox regression and Log-Rank testing. Group B comprises 315 patients of the following "low alcohol dose era" (mean amount of ethanol 0.8 +/- 0.4 ml, range 0.3-1.5 ml) and their mid-term survival (period to first regular 6-month post-procedural control). RESULTS: All patients (age 58 +/- 15 years, 99.2% follow up, mean 1.4 years): 33 patients died (5.1% all cause mortality), including perioperative deaths. 14/33 (42%) died from cardiac reasons. Annual total (all cause) mortality was 3.2%, total in-hospital mortality 1.2% in all patients (8 of 644 patients, 6 of them with severe comorbidity) and 0.4% in low risk patients. Annual cardiac mortality after hospital discharge was 0.7% (6 patients, all with sudden death). Group A (age 58 +/- 15 years, 98.8% follow up, mean 2.1 years, maximum 6.2 years): 29 patients died (total annual mortality 4.3%), 10 of them from hypertrophic cardiomyopathy related reasons resulting in a total in-hospital mortality of 1.8% (6 deaths), a cardiac annual mortality of 1.5% (including hospital mortality) and 0.6%/year after hospital discharge. Age was identified as an independent predictor of increased overall mortality (P = 0.002) and lower alcohol dosage and the absence of atrial fibrillation as independent predictors of reduced cardiac mortality (P = 0.005 and P = 0.039, respectively). With focus on the median value of the alcohol quantity (2.0 ml), patients treated with high amounts (>2.0 ml) showed a higher total mortality than patients treated with small amounts (< or =2.0 ml) (P = 0.031) and alcohol turned out to be an independent predictor of survival (P = 0.047). The same holds true for a homogenous subset of 262 patients with respect to cardiac mortality (P = 0.018). Group B (age 57 +/- 14 years, 99.7% follow up, mean 7.3 months): Total in-hospital mortality was 0.6% (2 of 315 patients; P = 0.173, group A/B) and cardiac in-hospital mortality 0% (P = 0.016, group A/B). During follow up two patients died, both of them experienced a sudden death reflecting an annual mortality of 1.0%. CONCLUSION: These data represent the largest available database on survival after alcohol septal ablation of HOCM from a single centre with large experience, and its evolution over 10 years with increasing procedural experience including the pronounced reduction of ethanol quantity in a systematic doses finding strategy. The in-hospital mortality has become very low. Cardiac survival during follow up was excellent, however, the well-known risk of sudden death is not completely eliminated. Longer follow-up time would be desirable for definite evaluation of this relatively new therapeutic option in the management of HOCM.

Transcoronary ablation of septal hypertrophy does not alter ICD intervention rates in high risk patients with hypertrophic obstructive cardiomyopathy.

INTRODUCTION: Transcoronary ablation of septal hypertrophy (TASH) is safe and effectively reduces the intraventricular gradient in patients with hypertrophic obstructive cardiomyopathy (HOCM). To analyze the potential of anti- and proarrhythmic effects of TASH, we studied the discharge rates of implanted cardioverter defibrillators (ICD) in patients with HOCM who are at a high risk for sudden cardiac death. METHODS: ICD and TASH were performed in 15 patients. Indications for ICD-implantation were secondary prevention in nine patients after resuscitation from cardiac arrest with documented ventricular fibrillation (n = 7) or sustained ventricular tachycardia (n = 2) and primary prevention in 6 patients with a family history of sudden deaths, nonsustained ventricular tachycardia, and/or syncope. All the patients had severe symptoms due to HOCM (NYHA functional class = 2.9). RESULTS: During a mean follow-up time of 41 +/- 22.7 months following the TASH procedure, 4 patients had episodes of appropriate discharges (8% per year). The discharge rate in the secondary prevention group was 10% per year and 5% in the group with primary prophylactic implants. Three patients died during follow-up (one each of pulmonary embolism, stroke, and sudden death). CONCLUSION: In conclusion, on the basis of ICD-discharge rates in HOCM-patients at high risk for sudden death, there is no evidence for an unfavorable arrhythmogenic effect of TASH. The efficacy of ICD treatment for the prevention of sudden cardiac death in HOCM could be confirmed, however, mortality is high in this cohort of hypertrophic cardiomyopathy patients.

Role of transcoronary ablation of septal hypertrophy in patients with hypertrophic cardiomyopathy, New York Heart Association functional class III or IV, and outflow obstruction only under provocable conditions.

BACKGROUND: Transcoronary ablation of septal hypertrophy (TASH) for hypertrophic cardiomyopathy seems to be an effective alternative to surgical myectomy. It remains a point of debate whether an outflow obstruction at rest is a necessary criterion for interventional therapy. METHODS AND RESULTS: TASH was compared in 45 consecutive patients with no resting gradient and a provocable gradient of > or =30 mm Hg (group I) and in 84 consecutive patients with a resting gradient of > or =30 mm Hg (80+/-33 mm Hg) (group II). At baseline, all patients were in NYHA functional class (FC) III or IV, unresponsive to medical treatment. Patients in group I were older (63+/-12 versus 55+/-17 years, P=0.005) and had a lower postextrasystolic gradient (110+/-44 versus 171+/-40 mm Hg, P<0.001). The groups were similar with respect to NYHA FC (3.1+/-0.3 versus 3.1+/-0.3), basal septal thickness (22+/-4 versus 23+/-3 mm), maximal oxygen consumption (13.1+/-4.6 versus 14.5+/-5.0 mL/kg per minute), and pulmonary artery mean pressure at workload (42+/-9 versus 42+/-10 mm Hg) (P>0.05). Median follow-up was 7 months after TASH. The 2 groups showed a significant and similar improvement in provocable obstruction (to 24+/-24 and 56+/-51 mm Hg, respectively), basal septal thickness (to 12+/-3 and 12+/-4 mm, respectively), NYHA FC (to 1.7+/-0.6 and 1.5+/-0.6, respectively), maximal oxygen consumption (to 16.0+/-5.3 and 16.6+/-6.0 mL/kg per minute, respectively), and pulmonary artery mean pressure at workload (to 36+/-9 and 34+/-9 mm Hg, respectively) (P>0.05). CONCLUSIONS: TASH seems to have beneficial clinical and hemodynamic effects in patients with either provocable or resting outflow obstruction.