Twenty Years of Alcohol Septal Ablation in Hypertrophic Obstructive Cardiomyopathy

Alcohol Septal Ablation for Hypertrophic Cardiomyopathy Guided by Intracoronary Myocardial Contrast Echocardiography to Reduce Myocardial Damage

Septal reduction therapy (SRT) is indicated for drug-refractory hypertrophic obstructive cardiomyopathy (HOCM). SRT includes surgical myectomy and alcohol septal ablation (ASA). The outcome between SRTs are similar except complete atrioventricular (AV) block. Intracoronary myocardial contrast echocardiography is used to minimize myocardial damage by ASA. We report a case of 40-year-old male who was diagnosed of HOCM with progressed symptoms under optimal medication. Echocardiography revealed peak velocity cross left ventricular outflow tract (LVOT) 5.3 m/s, systolic anterior motion (SAM) of mitral valve with eccentric mitral regurgitation (MR) and interventricular septal thickness 16 mm. Alcohol (99.5%) 1.5 mL was injected into the first small branch of the first septal artery, under precise localization by intracoronary myocardial contrast echocardiography. The pressure gradient of apex-LVOT-aorta reduced from 90 to 20 mmHg after ASA. No AV block was noted after the procedure and echocardiography revealed improved peak velocity cross LVOT and interventricular septal thickness. No more SAM or eccentric MR was observed. Previous studies recommended ASA reserved for patients with higher surgical risk and severe comorbidities. However, a recent study showed that young adults had better long-term survival and only one-half pacemaker implantation rate than older group following ASA. Under the guidance of intracoronary myocardial contrast, target vessel could be precisely localized to small branch from a septal artery to decrease myocardial damage. Therefore, ASA may be considered as the first-line SRT for symptomatic HOCM due to minimal invasiveness and effective outcome.

Predictors of cardiovascular implantable electronic device dependence at long-term follow-up after alcohol septal ablation in hypertrophic cardiomyopathy patients

BACKGROUND

The most common complication of alcohol septal ablation (ASA) is transient periprocedural high-grade AV block (HGAVB). To date, no long-term follow-up of cardiovascular implantable electronic device (CIED) utilization after ASA has been reported. We hypothesized that CIED dependence on long-term follow-up can be predicted by ECG or procedural characteristics.

METHODS

We analyzed all patients with HCM who underwent ASA from December 1998 to December 2019 and received their first CIED within 30 days after ASA for HGAVB. All follow-up interrogations were reviewed. CIED dependence was defined as ventricular pacing of ≥ 5%.

RESULTS

A total of 138 patients with HCM underwent ASA. Of these, 35 had a prior device and were excluded. Of the remaining 103 patients, 25 patients received a CIED for HGAVB within 30 days after ASA. Average follow-up duration was 10.1 years. On long-term follow-up, 16 patients (64%) were found to be CIED-dependent. Baseline characteristics, including pre- and post-ASA ECG, were not significantly different between dependent and non-dependent patients. The only predictor for CIED dependence was > 1 ml of alcohol injected (OR 6.0, p = 0.031).

CONCLUSIONS

CIED implantation after ASA is common. Almost two thirds of patients who received a CIED for post-procedural HGAVB were CIED-dependent on long-term follow-up. CIED dependence can be predicted by the amount of injected alcohol > 1 ml.

Hypertrophic Cardiomyopathy: A Cardiovascular Challenge Becoming a Contemporary Treatable Disease

Hypertrophic cardiomyopathy is one of the most common genetic inherited diseases of myocardium, which is caused by mutation in genes encoding proteins for the cardiac sarcomere. It is the most frequent cause of sudden death in young people and trained athletes. All diagnostic methods, including heart catheterization, transthoracic and transesophageal echocardiography, magnetic resonance imaging, genetic counseling and tissue biopsy are required for risk and therapy stratification and should be individualized depending on phenotype and genotype. Current therapy has not been tested adequately. Beta-blockers and verapamil can cause hypotension which can make hypertrophic cardiomyopathy worse. Disopyramide has been inadequately studied, and mavacamten was only studied in small trials. More definitive trials are currently ongoing. Novel invasive and noninvasive diagnostics, medical therapies, interventional and surgical approaches tend to influence the natural history of the disease, favoring a better future for this patient population.

Ten Steps in Adoption of Emerging Procedural Techniques: An Experience With Ethanol Ablation of Vein of Marshall (VOM)

Proceduralists must update their skill sets to provide patients with better care because of the addition of new and effective strategies post-training. For example, the current procedural strategy of pulmonary vein isolation for treating persistent atrial fibrillation (AF) is inadequate. However, the addition of ethanol ablation of the vein of Marshall (VOM), a relatively new procedural technique, can improve outcomes. Furthermore, the purpose of this report was to briefly explain VOM ethanol ablation, its role in atrial fibrillation and atypical flutter ablation, and to provide a template for performing a new procedural technique in the field.

Alcohol septal ablation: A useful tool in our arsenal against hypertrophic obstructive cardiomyopathy

OBJECTIVE

Affecting 1 in 500 individuals; hypertrophic cardiomyopathy is an autosomal dominant cardiovascular disorder which is prevalent throughout the world. Surgical myectomy (SM) and alcohol septal ablation (ASA) are two methods currently used for the management of drug refractory hypertrophic obstructive cardiomyopathy (HOCM). ASA may prove to be a useful, less invasive treatment in patients with HOCM METHODS: Electronic literature search was conducted to identify articles that discussed methods to treat drug refractory HOCM. No limits were placed on timing of the publication or the type of article. Keywords and MeSH terms were used and the results were summarized in the relevant section.

RESULTS

Current evidence suggests that alcohol septal ablation is a safe and effective procedure in treating patients with HOCM with similar short- and long-term outcomes when compared with SM.

CONCLUSION

ASA has been shown to be a safe and reliable procedure; imaging techniques and dedicated multi-disciplinary teams can be used to select patients with HOCM. Though SM is recommended as gold standard treatment for drug refractory HOCM, ASA may play an increasing role in the near future due an ageing population; both ASA and SM can have a beneficial role in treating those who are affected by HOCM when the appropriate group of patients are selected for each intervention.

Percutaneous Intramyocardial Septal Radiofrequency Ablation for Interventricular Septal Reduction: An Ovine Model with 1-Year Outcomes

BACKGROUND

Percutaneous intramyocardial (PIM) septal radiofrequency ablation (SRA) is a novel treatment approach for hypertrophic obstructive cardiomyopathy patients, but there has been lack of a large animal model to study PIM-SRA. We aimed to validate the long-term safety and efficacy of PIM-SRA and to observe pathological changes of the ablated interventricular septum (IVS) in a healthy sheep model.

METHODS AND RESULTS

Twelve sheep were randomized to the PIM-SRA group (n = 6) and the sham group (n = 6). In the PIM-SRA group, a radiofrequency (RF) electrode was inserted into the IVS with a maximum power of 80 W for 5 min. In the sham group, the RF electrode tip was positioned in the IVS segment but without RF power delivery. Septal hypokinesis was seen in all PIM-SRA group animals immediately after the procedure; the systolic wall thickening rate and motion amplitude of the ablated region decreased (p < 0.01), and the diastolic IVS thickness also decreased significantly over time (p < 0.01). ECG showed that all the sheep had normal sinus rhythm during the follow-up. Pathological examinations revealed scar tissue in the ablated region as expected.

CONCLUSIONS

PIM-SRA produced precisely ablated myocardial tissue, reduced the IVS thickness significantly, preserved the global LV function, and avoided the incidence of conduction system damage in the long term. PIM-SRA was found to be a safe and effective minimally invasive septal reduction therapy.

Transcatheter septal ablation in hypertrophic obstructive cardiomyopathy: a technical guide and review of published results

Transcatheter alcohol septal ablation (ASA) treatment of symptomatic patients with hypertrophic obstructive cardiomyopathy (HOCM) is based on the existence and degree of intraventricular obstruction. Patients with significant gradient and symptoms who do not respond to optimal medical therapy are eligible to gradient reduction through a surgical (septal myectomy) or a transcatheter (alcohol septal ablation) septal reduction. The latter encompasses occlusion of a septal branch perfusing the hypertrophied septum, which is involved in the generation of obstruction, by injecting ethanol into the supplying septal branch(es). ASA has been established as a highly effective and safe method and has outnumbered the surgical gold standard. Although the technique is straightforward, patient selection and some technical details may influence the efficacy and safety of the procedure. The technique is based on echocardiographic contrast guidance, which allows accurate target septal branch selection and optimisation of the result. Published long-term results from high-volume centres have confirmed the effectiveness of ASA and have shown excellent survival, which is comparable to that in the general population. Choice and performance of the surgical or interventional treatment should be implemented in highly specialised centres in terms of a heart-team approach, taking notice of anatomic characteristics as well as comorbidities. Involvement of all cases in international registries may reveal the individual merits and indications for the surgical and interventional treatment in HOCM.