Predictors of Complete Heart Block After Transcoronary Ablation of Septal Hypertrophy

Permanent pacemaker implantation after alcoholic septal ablation induced complete heart block: Long-term impact

INTRODUCTION AND OBJECTIVES

Patients with hypertrophic obstructive cardiomyopathy (HOCM) that remain symptomatic despite optimized medical therapy often undergo alcohol septal ablation (ASA). One of the most frequent complications is complete heart block (CHB), requiring a permanent pacemaker (PPM) in variable rates of up to 20% of patients. The long-term impact of PPM implantation in these patients remains unclear. This study aimed to evaluate the long-term clinical outcomes in patients who implant PPM after ASA.

METHODS

Patients who underwent ASA at a tertiary center were consecutively and prospectively enrolled. Patients with previous PPM or implantable cardio-defibrillator were excluded from this analysis. Patients with and without PPM implantation after ASA were compared based on their baseline characteristics, procedure data and three-year primary endpoint of composite of all-cause mortality and hospitalization and secondary endpoint of composite of all-cause mortality and cardiac cause hospitalization.

RESULTS

Between 2009 and 2019, 109 patients underwent ASA, 97 of whom were included in this analysis (68% female, mean age 65.2 years old). 16 patients (16.5%) required PPM implantation for CHB. In these patients, no vascular access, pacemaker pocket or pulmonary parenchyma complications were noted. The baseline characteristics of comorbidities, symptoms, echocardiographic and electrocardiographic findings were identical in the two groups, with higher mean age (70.6±10.0 years vs. 64.1±11.9 years) and lower beta-blocker therapy rate (56% vs. 84%) in the PPM group. Procedure-related data showed higher creatine kinase (CK) peaks in the PPM group (1692 U/L vs. 1243 U/L), with no significant difference in the alcohol dose. At three years after ASA procedure, there were no differences in the primary and secondary endpoints between the two groups.

CONCLUSIONS

Permanent pacemaker after ASA induced CHB do not affect long term prognosis in hypertrophic obstructive cardiomyopathy patients.

Iatrogenic Atrioventricular Block

Iatrogenic atrioventricular (AV) block can occur in the context of cardiac surgery, percutaneous transcatheter, or electrophysiologic procedures. In cardiac surgery, patients undergoing aortic and/or mitral valve surgery are at the highest risk for developing perioperative AV block requiring permanent pacemaker implantation. Similarly, patients undergoing transcatheter aortic valve replacement are also at increased risk for developing AV block. Electrophysiologic procedures, including catheter ablation of AV nodal re-entrant tachycardia, septal accessory pathways, para-Hisian atrial tachycardia, or premature ventricular complexes, are also associated with risk of AV conduction system injury. In this article, we summarize the common causes for iatrogenic AV block, predictors for AV block, and general management considerations.

Sex-Related Differences among Adults with Hypertrophic Obstructive Cardiomyopathy Undergoing Transcoronary Ablation of Septal Hypertrophy

(1) Background: The transcoronary ablation of septal hypertrophy (TASH) is an established therapy for hypertrophic obstructive cardiomyopathy (HOCM). Previous studies on this topic are characterised by a consistent male predominance and show a worse prognosis in females. (2) Methods: This study is a retrospective analysis of all TASH procedures conducted between 2006 and 2021 at a tertiary academic centre. A solution of 75 µm microspheres (Embozene^®, Boston Scientific, Marlborough, MA, USA) was used as an embolising agent. The outcomes of interest were left ventricular outflow tract (LVOT) gradient reduction and symptom improvement among males vs. that among females. Secondarily, we analysed the sex-related differences in procedural safety outcomes and mortality. (3) Results: The study population consisted of 76 patients, with a median age of 61 years. Females comprised 57% of the cohort. We observed no sex-related differences in the baseline LVOT gradients at rest or under provocation (p = 0.560 and p = 0.208, respectively). Females were significantly older at the time of the procedure (p < 0.001), had lower tricuspid annular systolic excursion (TAPSE) (p = 0.009), presented a worse clinical status according to the NYHA functional classification (for NYHA ≥ 3, p < 0.001), and were more often on diuretics (p < 0.001). We did not observe sex-related differences in absolute gradient reduction at rest (p = 0.147) and under provocation (p = 0.709). There was a reduction in the NYHA class by a median value of 1 (p = 0.636) at follow-up for both sexes. Postprocedural access site complications were documented in four cases (two of which concerned females), and complete atrioventricular block was noted in five patients (three of which concerned females). The 10-year survival rates were comparable between the sexes (85% in females and 88% in males). The female sex was not associated with enhanced mortality according to multivariate analysis after adjusting for the confounding variables (HR 0.94; 95% CI 0.376-2.350; p = 0.895), but we observed age-related differences in long-term mortality (HR 1.035; 95% CI 1.007-1.063; p = 0.015). (4) Conclusions: TASH is safe and effective in both sexes, irrespective of their clinical differences. Women present at an advanced age and with more severe symptoms. An advanced age at the time of the intervention is an independent predictor of mortality.

Opportunities and drawbacks of the subcutaneous defibrillator across different clinical settings

INTRODUCTION

The subcutaneous implantable cardioverter-defibrillator (S-ICD) is an established therapy for the prevention of sudden cardiac death (SCD) and an alternative to a transvenous implantable cardioverter-defibrillator system in selected patients. Beyond randomized clinical trials, many observational studies have described the clinical performance of S-ICD across different subgroups of patients.

AREAS COVERED

Our review aimed to describe the opportunities and drawbacks of the S-ICD, focusing on their use in special populations and across different clinical settings.

EXPERT OPINION

The choice to implant S-ICD should be based on the patient's tailored approach, which takes into account the adequate S-ICD screening at rest or during stress, the infective risk, the ventricular arrhythmia susceptibility, the progressive nature of the underlying disease, the work or sports activity, and the risk of lead-related complications.

Gender disparities in alcohol septal ablation for hypertrophic obstructive cardiomyopathy

OBJECTIVE

Alcohol septal ablation (ASA) improves symptoms in hypertrophic obstructive cardiomyopathy (HOCM). We conducted a large retrospective analysis investigating gender effects on outcome after ASA.

METHODS AND RESULTS

1367 ASAs between 2002 and 2020 were analysed. Women (47.2%) were older (66.0 years (IQR 55.0-74.0) vs 54.0 years (IQR 45.0-62.0); p<0.0001) with more severe symptoms. The interventricular septal diameter (IVSD) was higher in men (21.0 mm (IQR 19.0-24.0) vs 20.0 mm (IQR 18.0-23.0); p<0.0001) but the IVSD indexed to body surface area was higher in women (10.9 mm/m² (IQR 9.7-12.7) vs 10.2 mm/m² (IQR 9.0-11.7); p<0.0001). Women had lower exercise-induced left ventricular outflow tract gradients (LVOTG) 1-4 days after ASA (55.0 mm Hg (IQR 30.0-109.0) vs 71.0 mm Hg (IQR 37.0-115.0); p=0.0006). There was a trend for lower resting LVOTG 1-4 days after ASA (20.0 mm Hg (IQR 12.0-37.5) vs 22.0 mm Hg (IQR 13.0-40.0); p=0.0062) and lower exercise-induced LVOTG after 6 months in women (34.0 mm Hg (IQR 21.0-70.0) vs 43.5 mm Hg (IQR 25.0-74.8); p=0.0072), but this was not statistically significant after Bonferroni correction. More women developed atrioventricular (AV) block (20.3% vs 13.3%; p=0.0005) and required a pacemaker (17.4% vs 10.4%; p=0.0002) but not a cardioverter defibrillator (9.0% vs 11.6% in men; p=n .s.). However, in multivariable regression models, there was no evidence that sex independently influenced LVOTG and the occurrence of AV block.

CONCLUSION

Female patients with HOCM were older and had more advanced disease at the time of ASA. Women had superior short-term haemodynamic response to ASA but more often developed AV block after ASA. These results are important to consider for sex-specific counselling before ASA.

Percutaneous transluminal septal myocardial ablation: past, present, and future

About 30% of patients with hypertrophic cardiomyopathy have a significant left ventricular pressure gradient at rest, and 60%-70% of these patients are diagnosed with hypertrophic obstructive cardiomyopathy (HOCM) because an induced pressure gradient is also present. Percutaneous transluminal septal myocardial ablation (PTSMA) is a procedure in which ethanol is used to ablate the portion of the septal myocardium that is involved in the pathogenesis of the left ventricular outflow tract pressure gradient (LVOT PG). In 1995, Sigwart et al. reported three cases of PTSMA in The Lancet. The introduction of PTSMA into clinical practice has enabled the reduction of LVOT PG and improvement of heart failure symptoms in elderly and high-risk patients with symptomatic, drug-refractory HOCM. In 1998, Faber et al. published a report in Circulation on selective septal myocardial ablation using myocardial contrast echocardiography (MCE). MCE-guided PTSMA is now recognized as the standard method of PTSMA in many countries and regions, including Europe, North America, and Asia, and is estimated to be performed on about 300 to 400 patients per year in Japan based on reports from the Japanese Circulation Society's Clinical Practice Survey. The current problems with this technique are: 1) the outcome is greatly influenced by operators' and institutional experience, and 2) it is difficult to determine in advance whether the patient is a PTSMA responder or not. Recently, advancements in imaging modalities, including cardiac computed tomography and magnetic resonance imaging, have facilitated clarification of the mechanisms of LVOT obstruction. Therefore, more appropriate decisions regarding PTSMA and surgical myectomy (SM) are now made. Better treatment selection will undoubtedly improve the prognosis of patients with drug-refractory HOCM complicated by heart failure, and further elucidation of the pathogenesis of LVOT obstruction and technical advances in PTSMA and SM are eagerly awaited.

Safety and efficacy of alcohol septal ablation in adolescents and young adults with hypertrophic obstructive cardiomyopathy

INTRODUCTION

Data regarding alcohol septal ablation (ASA) in young patients with hypertrophic obstructive cardiomyopathy (HOCM) are scarce. The purpose of our study is to evaluate the safety and efficacy of ASA in patients ≤ 25 years.

METHODS AND RESULTS

All ASAs between 2002 and 2020 at our institution were assigned to a group of patients 14-25 years of age (group 1) and a reference group > 25 years (group 2). 1,264 procedures were analysed in group 2 (58.6 ± 13.5 years) and 41 procedures in group 1 (20.9 ± 3.3 years). The baseline interventricular septal diameter (IVSD) was higher in group 1 (26.0 ± 6.5 mm vs. 21.3 ± 4.4 mm; p < 0.0001). There was no difference in baseline left ventricular outflow tract gradient (LVOTG) (group 1: 54.4 ± 24.4 mmHg; group 2: 52.4 ± 36.6 mmHg; p = n.s.). A previous cardiac device was more often observed in group 1 (31.7% vs. 9.0%; p < 0.0001). Symptoms were improved after 6 months (group 1: mean NYHA class 2.5 at baseline and 1.3 at FU; p < 0.0001; group 2: mean NYHA class 2.7 at baseline and 1.4 at FU; p <0 .0001). IVSD (group 1: 20.3 ± 8.2 mm; group 2: 16.8 ± 5.7 mm; p < 0.0001 for each group compared to baseline) and LVOTG improved during FU (group 1: 25.5 ± 20.0 mmHg; group 2: 22.1 ± 21.7 mmHg; p < 0.0001 for each group). Intrahospital mortality was 0.0% in patients 14-25 years and 0.9% in the reference group. Persistent AV-block was observed in 12.2% of the group 1 and 15.9% of the group 2 patients (p = n.s.).

CONCLUSION

ASA is safe and effective in HOCM patients 14-25 years of age in experienced centres.

Iatrogenic Atrioventricular Block

Iatrogenic atrioventricular (AV) block can occur in the context of cardiac surgery, percutaneous transcatheter, or electrophysiologic procedures. In cardiac surgery, patients undergoing aortic and/or mitral valve surgery are at the highest risk for developing perioperative AV block requiring permanent pacemaker implantation. Similarly, patients undergoing transcatheter aortic valve replacement are also at increased risk for developing AV block. Electrophysiologic procedures, including catheter ablation of AV nodal re-entrant tachycardia, septal accessory pathways, para-Hisian atrial tachycardia, or premature ventricular complexes, are also associated with risk of AV conduction system injury. In this article, we summarize the common causes for iatrogenic AV block, predictors for AV block, and general management considerations.

Relationship Between Procedural Right Bundle Branch Block and 1-Year Outcome After Alcohol Septal Ablation for Hypertrophic Obstructive Cardiomyopathy - A Retrospective Study

BACKGROUND

Alcohol septal ablation (ASA) is a treatment option in patients with drug-refractory symptomatic hypertrophic obstructive cardiomyopathy (HOCM). In many patients, right bundle branch block (RBBB) develops during ASA because septal branches supply the right bundle branch. However, the clinical significance of procedural RBBB is uncertain.

METHODS AND RESULTS

We retrospectively reviewed 184 consecutive patients with HOCM who underwent ASA. We excluded 40 patients with pre-existing RBBB (n=10), prior pacemaker implantation (n=15), mid-ventricular obstruction type (n=10), and those lost to follow-up (n=5), leaving 144 patients for analysis. Patients were divided into 2 groups according to the development (n=95) or not (n=49) of procedural RBBB. ASA conferred significant decreases in the left ventricular pressure gradient (LVPG) in both the RBBB and no-RBBB group (from 74±48 to 27±27 mmHg [P<0.001] and from 75±45 to 31±33 mmHg [P<0.001], respectively). None of the RBBB patients developed further conduction system disturbances. The percentage reduction in LVPG at 1 year after the procedure was significantly greater in the RBBB than no-RBBB group (66±24% vs. 49±45%; P=0.035). Procedural RBBB was not associated with pacemaker implantation after ASA, but was associated with reduction in repeat ASA (odds ratio 0.34; 95% confidence interval 0.13-0.92; P=0.045).

CONCLUSIONS

Although RBBB frequently occurs during the ASA procedure, it does not adversely affect clinical outcomes.

Delayed reversibility of complete atrioventricular block: cardio-biliary reflex after alcohol septal ablation in a patient with hypertrophic obstructive cardiomyopathy

Background

Complete atrioventricular block (AVB) is a life-threatening condition that usually occurs in elderly people with organic heart disease. We herein describe a rare case of complete AVB in a young man with hypertrophic obstructive cardiomyopathy (HOCM) complicated by cholecystitis and cholangitis. Both cardio-biliary reflex and alcohol septal ablation (ASA) can cause conduction block, but the latter is often irreversible. However, their simultaneous occurrence in a patient has not been reported.

Case presentation

A 31-year-old man presented with acute cholecystitis and cholangitis and complete AVB, which had been diagnosed at a local hospital on the third day after onset. On the fourth day, he was transferred to the emergency department of our hospital because of persistent complete AVB, although his abdominal pain had been partially relieved. An echocardiogram showed a remarkably elevated left ventricular outflow tract (LVOT) gradient (105.2 mmHg) despite the performance of ASA 9 years previously. The abdominal pain gradually disappeared, and normal sinus rhythm was completely recovered 11 days after onset. We determined that cardio-biliary reflex was the cause of the AVB because of the absence of other common causes. Finally, the patient underwent implantation of a permanent pacemaker to reduce the LVOT obstruction and avoid the risk of AVB recurrence.

Conclusions

Cholecystitis is a rare cause of complete AVB, which is a difficult differential diagnosis when complicated by HOCM after ASA. Clinicians should be alert to the possibility of cholecystitis in patients with abdominal pain and an unknown cause of bradycardia, complete AVB, or even sinus arrest.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02165-5.

Predicting complete heart block after alcohol septal ablation for hypertrophic cardiomyopathy using a risk stratification model and clinical tool

BACKGROUND

Alcohol septal ablation (ASA) is a proven method of septal reduction for patients with drug refractory, symptomatic hypertrophic obstructive cardiomyopathy (HOCM). This procedure is associated with a 6.5-11% risk of complete heart block (CHB).

OBJECTIVE

The aim of this study is to determine factors that predict CHB and to develop a clinical tool for risk stratification of patients.

METHODS

Patients were enrolled into an ongoing ASA study. A total of 636 patient procedures were included, 527 of whom were used in the development of the prediction tool, and 109 of whom were used for independent validation. Multivariate analysis was performed with odds ratios used to develop the clinical prediction tool. This was then internally and externally validated.

RESULTS

Of the 527 in the prediction cohort, 46 developed CHB. The predictors of CHB were age ≥50 years, pre-ASA left bundle branch block (LBBB), transient procedural high-grade block, post-ASA PR prolongation ≥68 ms, and new bifascicular block. An 11-point clinical prediction tool was developed to classify these factors. Internal validation using a receiver operating characteristic curve revealed an area under the curve of 0.88 for the clinical prediction tool. External validation using 109 contemporary patients revealed a 98% negative predictive value, 24% positive predictive value, 75% sensitivity, and 81% specificity in high-risk patients.

CONCLUSION

Among patients undergoing ASA, the risk of CHB can be predicted with easily obtained clinical and electrocardiographic factors. This clinical prediction tool allows identification of high-risk patients who may benefit from additional monitoring and therapy.

Alcohol-induced right bundle branch block is associated with a benign outcome in HOCM after alcohol septum ablation (ASA)

INTRODUCTION

Alcohol septum ablation (ASA) is a treatment option for hypertrophic obstructive cardiomyopathy (HOCM). We examined the impact of ASA-induced bundle branch block (BBB) on clinical and hemodynamic features.

METHODS AND RESULTS

We retrospectively analysed 98 HOCM patients with regard to ASA-induced BBB. Clinical examination was performed at baseline, early after ASA and at chronic follow-up (FU). ASA reduced left ventricular outflow tract gradient (LVOTG) during chronic FU (69.2 ± 41.6 pre vs. 31.8 ± 30.3 mmHg post ASA; p < 0.05) and interventricular septal diameter (21.7 ± 3.4 pre vs. 18.7 ± 5.0 mm post ASA; p < 0.05). ASA-induced early right BBB (RBBB) until discharge was observed in 44.9% and chronic RBBB at FU in 32.7%. Left BBB (LBBB) occurred in 13.3% early after ASA and in only 4.1% at chronic FU. Chronic RBBB was associated with more pronounced exercise-induced LVOTG reduction (102.1 ± 55.2 with vs. 73.6 ± 60.0 mmHg without; p < 0.05). 6-min-walk-test (6-MWT) and NYHA class were not affected by RBBB. LBBB had no influence on LVOTG, 6-MWT and symptoms. More ethanol was injected in patients with early RBBB (1.1 ± 0.4 vs. 0.8 ± 0.3 ml without; p < 0.05), who also showed higher mean CK release (827 ± 341 vs. 583 ± 279 U/l without; p < 0.05). Pacemaker implantation during FU was necessary in 11.5% of patients with early RBBB, 3.1% with chronic RBBB, 7.7% with early LBBB and 0% with chronic LBBB (p = n.s. for BBB vs. no BBB).

CONCLUSION

ASA-induced RBBB is associated with a higher volume of infused ethanol and higher maximum CK release. RBBB does not adversely affect the clinical outcome or need for pacemaker implantation but was associated with higher exercise-induced LVOTG reduction during chronic FU.

Looking back on 15 years of ultrasound-guided alcohol septal ablation for hypertrophic obstructive cardiomyopathy

Background: Septal reduction remains an important target of current therapeutic modalities in hypertrophic obstructive cardiomyopathy (HOCM). Surgical septal myectomy has long been considered the gold standard in pharmacotherapy-refractory severely symptomatic patients with marked left ventricular outflow tract (LVOT) obstruction. In recent years, percutaneous alcohol septal ablation (ASA) has matured into the preferred strategy for patients with favourable anatomy and no other coexisting surgically amenable disease.Methods: We discuss 26 HOCM patients with persistent dyspnoea, angina or syncope despite optimal medical treatment. Baseline septal wall thickness was 20 ± 3 mm, with peak resting/provoked LVOT gradients of 53 ± 35/112 ± 40 mmHg. Guided by echocardiography, alcohol injection could be restricted to the first septal coronary artery in 85% of patients, provoking basal septal infarction with average troponin rise of 3.0 ng/ml.Results: Eighty-six per cent of patients experienced sustained clinical improvement, associated with a reduction of septal wall thickness to 15 ± 3 mm and resting LVOT gradient to 21 ± 15 mmHg. One of the two non-responders underwent additional septal myectomy 11 years after ASA. Notable adverse events during the follow-up of 7.2 ± 4.7 years included: persistent conduction disturbances (65%) necessitating early postprocedural permanent pacemaker implantation (15%); atrial fibrillation (32%); ventricular tachycardia (4%) and aortic stenosis (14%). Six patients died, of which only 1 cardiac death.Conclusions: Our case series underscores the efficacy of ASA at relieving LVOT obstruction and improving symptoms in properly selected HOCM patients, with acceptably low procedural and long term mortality and morbidity.

Risk of arrhythmic events after alcohol septal ablation for hypertrophic cardiomyopathy using continuous implantable cardiac monitoring

BACKGROUND

Alcohol septal ablation (ASA) in patients with hypertrophic cardiomyopathy (HCM) can lead to heart rhythm disturbances including complete heart block (CHB) and atrial and ventricular arrhythmias.

OBJECTIVE

We aimed to evaluate the utility of long-term arrhythmia monitoring with an implantable cardiac monitor (ICM) after ASA.

METHODS

Between February 2014 and March 2019, 56 patients with HCM undergoing ASA were enrolled in a prospective study and underwent ICM implantation. Kaplan-Meier survival analysis was used to assess the rate of ICM-detected arrhythmic events.

RESULTS

The mean age was 59 ± 11 years, and 20 (36%) were women. The median (25th, 75th percentile) resting left ventricular outflow tract gradient obtained by echocardiography was 43 (22, 81) mm Hg. Greater than 1 septal perforating artery was injected in 48 patients (86%). The Kaplan-Meier cumulative rate of ICM-detected arrhythmic events at 18 months of follow-up was 71%, with an event rate of 43% occurring within 3 months of ASA. The cumulative rate of the ICM-detected first atrial fibrillation event at 18 months was 37%, and the corresponding rate of CHB was 19%. All atrial fibrillation and CHB events were actionable, leading to the initiation of anticoagulation and pacemaker implantation, respectively. No baseline demographic or procedural variables were identified as independent predictors of an increased risk of developing ICM-detected arrhythmic events.

CONCLUSION

After ASA, ICM is effective in capturing clinically actionable arrhythmic events in patients with HCM regardless of patient's baseline risk factors.

Temporal Occurrence of Arrhythmic Complications After Alcohol Septal Ablation

BACKGROUND

The temporal occurrence of arrhythmic complications after alcohol septal ablation (ASA) is unclear. As a result, the appropriate time to monitor patients after ASA is controversial. The purpose of this study is to determine the temporal occurrence of complete heart block (CHB) and ventricular tachyarrhythmia (VT) after ASA to better understand when patients can be safely discharged.

METHODS

Consecutive patients treated with ASA for hypertrophic cardiomyopathy from 2003 to 2019 at a tertiary referral center were reviewed retrospectively. The incidence and timing of CHB or sustained VT within 30 days post-ASA were assessed.

RESULTS

A total of 243 patients were included in this study. Mean maximal septal thickness was 19.0±3.9 mm, and total volume of ethanol injected was 1.7±0.6 mL. CHB occurred in 59 (24.3%) patients, including transient CHB in 33 (13.6%) and permanent in 26 (10.7%). The initial episode of CHB occurred within 24 hours post-ASA in 51 (21.0%) patients, between 24 and 48 hours in 3 (1.2%), between 48 and 72 hours in 3 (1.2%), and after 72 hours in 2 (0.8%). New permanent pacemaker was placed in 46 (18.3%). Presence of baseline bundle branch block and age ≥70 were significantly associated with CHB but not CHB presenting after 24 hours. VT occurred in 3 (1.2%) patients, including 1 (0.4%) within 24 hours, 1 (0.4%) between 24 and 48 hours, and 1 (0.4%) after 72 hours. VT required cardioversion in 2 patients and new implantable cardioverter-defibrillator placement in 2.

CONCLUSIONS

The incidence of CHB or VT presenting after 72 hours post-ASA was low. These findings suggest that timely discharge of patients without evidence of early conduction disturbances after ASA can be considered as a potentially safe management strategy, especially in patients without preexisting conduction abnormalities.

Procedural complication and long term outcomes after alcohol septal ablation in patients with obstructive hypertrophic cardiomyopathy: data from China

Data on procedural complications and long term survival after alcohol septal ablation (ASA) in Chinese patients with obstructive hypertrophic cardiomyopathy (HOCM) are lacking. We aimed to investigate long-term survival of HOCM patients after ASA and compared to the non-obstructive hypertrophic cardiomyopathy(NOHCM). A total of 233 patients with HOCM and a peak pressure gradient of ≥50 mm Hg at rest or with provocation were consecutively enrolled from Fuwai Hospital in China between 2000 and 2012. Another 297 patients without left ventricular outflow tract obstruction were regarded as control group. Periprocedural mortality of ASA were low (0.89%). Periprocedural lethal ventricular arrhythmia occurred in 9 patients (4.0%). Alcohol volume (RR 1.44, 95% CI: 1.03–2.03, P = 0.034) and age ≤40 years old (RR 4.63, 95% CI: 1.07–20.0, P = 0.040) were independent predictors for periprocedural lethal ventricular arrhythmia. The 10- year overall survival was 94.6% in the ASA group, similar with 92.9% in the NOHCM group (P = 0.930). In conclusion, periprocedural mortality and complications were rare in ASA. Long term survival after ASA were satisfactory and comparable to NOHCM. Patients under 40 years old should be more cautious undergoing ASA, for these patients were more likely to endure lethal ventricular arrhythmia during periprocedural period of ASA.

Long-Term Outcome of Alcohol Septal Ablation for Obstructive Hypertrophic Cardiomyopathy in the Young and the Elderly

OBJECTIVES

The aim of this study was to compare outcomes of alcohol septal ablation (ASA) in young and elderly patients with obstructive hypertrophic cardiomyopathy (HCM).

BACKGROUND

The American College of Cardiology Foundation/American Heart Association guidelines reserve ASA for elderly patients and patients with serious comorbidities. Information on long-term age-specific outcomes after ASA is scarce.

METHODS

This cohort study included 217 HCM patients (age 54 ± 12 years) who underwent ASA because of symptomatic left ventricular outflow tract obstruction. Patients were divided into young (age ≤55 years) and elderly (age >55 years) groups and matched by age in a 1:1 fashion to nonobstructive HCM patients.

RESULTS

Atrioventricular block following ASA was more common in elderly patients (43% vs. 21%; p = 0.001), resulting in pacemaker implantation in 13% and 5%, respectively (p = 0.06). Residual left ventricular outflow tract gradient, post-procedural New York Heart Association functional class, and necessity for additional septal reduction therapy was comparable between age groups. During a follow-up of 7.6 ± 4.6 years, 54 patients died. The 5- and 10-year survival following ASA was 95% and 90% in patients age ≤55 years and 93% and 82% in patients age >55 years, which was comparable to their control groups. The annual adverse arrhythmic event rate following ASA was 0.7%/year in young patients and 1.4%/year in elderly patients, which was comparable to their control groups.

CONCLUSIONS

ASA is similarly effective for reduction of symptoms in young and elderly patients; however, younger patients have a lower risk of procedure-related atrioventricular conduction disturbances. The long-term mortality rate and risk of adverse arrhythmic events following ASA are low, both in young and elderly patients, and are comparable to age-matched nonobstructive HCM patients.

Results of ventricular septal myectomy and hypertrophic cardiomyopathy (from Nationwide Inpatient Sample [1998-2010])

Ventricular septal myomectomy (VSM) is the primary modality for left ventricular outflow tract gradient reduction in patients with obstructive hypertrophic cardiomyopathy with refractory symptoms. Comprehensive postprocedural data for VSM from a large multicenter registry are sparse. The primary objective of this study was to evaluate postprocedural mortality, complications, length of stay (LOS), and cost of hospitalization after VSM and to further appraise the multivariate predictors of these outcomes. The Healthcare Cost and Utilization Project's Nationwide Inpatient Sample was queried from 1998 through 2010 using International Classification of Diseases, Ninth Revision, procedure codes 37.33 for VSM and 425.1 for hypertrophic cardiomyopathy. The severity of co-morbidities was defined using the Charlson co-morbidity index. Hierarchical mixed-effects models were generated to identify independent multivariate predictors of in-hospital mortality, procedural complications, LOS, and cost of hospitalization. The overall mortality was 5.9%. Almost 9% (8.7%) of patients had postprocedural complete heart block requiring pacemakers. Increasing Charlson co-morbidity index was associated with a higher rate of complications and mortality (odds ratio 2.41, 95% confidence interval 1.17 to 4.98, p = 0.02). The mean cost of hospitalization was $41,715 ± $1,611, while the average LOS was 8.89 ± 0.35 days. Occurrence of any postoperative complication was associated with increased cost of hospitalization (+$33,870, p <0.001) and LOS (+6.08 days, p <0.001). In conclusion, the postoperative mortality rate for VSM was 5.9%; cardiac complications were most common, specifically complete heart block. Age and increasing severity of co-morbidities were predictive of poorer outcomes, while a higher burden of postoperative complications was associated with a higher cost of hospitalization and LOS.

Percutaneous Septal Ablation in Hypertrophic Obstructive Cardiomyopathy: From Experiment to Standard of Care

Hypertrophic cardiomyopathy (HCM) is one of the more common hereditary cardiac conditions. According to presence or absence of outflow obstruction at rest or with provocation, a more common (about 60-70%) obstructive type of the disease (HOCM) has to be distinguished from the less common (30-40%) nonobstructive phenotype (HNCM). Symptoms include exercise limitation due to dyspnea, angina pectoris, palpitations, or dizziness; occasionally syncope or sudden cardiac death occurs. Correct diagnosis and risk stratification with respect to prophylactic ICD implantation are essential in HCM patient management. Drug therapy in symptomatic patients can be characterized as treatment of heart failure with preserved ejection fraction (HFpEF) in HNCM, while symptoms and the obstructive gradient in HOCM can be addressed with beta-blockers, disopyramide, or verapamil. After a short overview on etiology, natural history, and diagnostics in hypertrophic cardiomyopathy, this paper reviews the current treatment options for HOCM with a special focus on percutaneous septal ablation. Literature data and the own series of about 600 cases are discussed, suggesting a largely comparable outcome with respect to procedural mortality, clinical efficacy, and long-term outcome.

Alcohol septal ablation for obstructive hypertrophic cardiomyopathy: outcomes in young, middle-aged, and elderly patients

OBJECTIVES

We compared the efficacy and safety of alcohol septal ablation (ASA) for obstructive hypertrophic cardiomyopathy (HCM) in young, middle-aged, and elderly patients.

BACKGROUND

Intersociety guidelines suggest based on limited evidence that young patients with medically refractory symptoms of obstructive HCM should undergo surgical myectomy while elderly patients may be more appropriate for ASA.

METHODS

Data for 360 patients undergoing 389 ASAs were prospectively collected and retrospectively analyzed according to age.

RESULTS

Young (<45 years), middle-aged (45-64 years), and elderly (≥65 years) patients comprised 28, 40, and 32% of the study population, respectively. Young patients had thicker left ventricular septal walls at baseline, and elderly patients had more comorbidity and dyspnea. Resting, mean left ventricular outflow tract gradients (LVOTGs) were similar across the age groups at baseline (62, 66, and 68 mm Hg, respectively; P = NS for all comparisons). LVOTGs and dyspnea were significantly and similarly improved in all age groups immediately after ASA and through 12 months of follow-up (P < 0.001 for before and after comparisons; P = NS for intergroup comparisons). Complication rates were similar for young and middle-aged patients but higher for elderly patients (9.1 and 6.3% vs. 20.8%, respectively; P ≤ 0.016 for elderly vs. others). Mortality rates for young and middle-aged patients were lower than for elderly patients, but the differences were not statistically significant.

CONCLUSIONS

Patients undergoing ASA had significant and similar improvements in LVOTGs and symptoms regardless of age. Procedural complications were increased in elderly patients, who had numerically but not statistically significantly higher mortality rates.