Short- and long-term outcome after alcohol septal ablation in obstructive hypertrophic cardiomyopathy: Experience of a reference center

Advancements in the Diagnosis and Treatment of Hypertrophic Cardiomyopathy: A Comprehensive Review

Hypertrophic cardiomyopathy (HCM) is characterized by excessive growth of myocardial tissue, most commonly due to genetic mutations in sarcomere proteins. This can lead to complications such as heart failure, mitral regurgitation, syncope, arrhythmias, sudden cardiac death, and myocardial ischemia. While we have come a long way in our understanding of the pathophysiology, genetics, and epidemiology of HCM, the past 10 years have seen significant advancements in diagnosis and treatment. As the body of evidence on hypertrophic cardiomyopathy continues to grow, a comprehensive review of the current literature is an invaluable resource in organizing this knowledge. By doing so, the vast progress that has been made thus far will be widely available to all experts in the field. This review provides a comprehensive analysis of the scientific literature, exploring both well-established and cutting-edge diagnostic and therapeutic options. It also presents a unique perspective by incorporating topics such as exercise testing, genetic testing, radiofrequency ablation, risk stratification, and symptomatic management in non-obstructive HCM. Lastly, this review highlights areas where current and future research is at the forefront of innovation in hypertrophic cardiomyopathy.

A systematic review of present and future pharmaco-structural therapies for hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is a common contemporary, treatable, genetic disorder that can be compatible with normal longevity. While current medical therapies are ubiquitous, they are limited by a lack of solid evidence, are often inadequate, poorly tolerated, and do not alter the natural disease course. As such, there has long been a need for effective, evidence-based, and targeted disease-modifying therapies for HCM. In this review, we redefine HCM as a treatable condition, evaluate current strategies for therapeutic intervention, and discuss novel myosin inhibitors. The majority of patients with HCM have elevated left ventricular outflow tract gradients, which predicts worse symptoms and adverse outcomes. Conventional pharmacological therapies for symptomatic HCM can help improve symptoms but are often inadequate and poorly tolerated. Septal reduction therapies (surgical myectomy and alcohol septal ablation) can safely and effectively reduce refractory symptoms and improve outcomes in patients with obstructive HCM. However, they require expertise that is not universally available and are not without risks. Currently, available therapies do not alter the disease course or the progressive cardiac remodeling that ensues, nor subsequent heart failure and arrhythmias. This has been regarded as an unmet need in the care of HCM patients. Novel targeted pharmacotherapies, namely cardiac myosin inhibitors, have emerged to reverse key pathophysiological changes and alter disease course. Their favorable outcomes led to the early Food and Drug Administration approval of mavacamten, a first-in-class myosin modulator, changing the paradigm for the pharmacological treatment of HCM.

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.

Alcohol Septal Ablation in Patients with Hypertrophic Obstructive Cardiomyopathy: A Contemporary Perspective

Alcohol septal ablation is a minimally invasive procedure for the treatment of left ventricular outflow tract (LVOT) obstruction in patients with hypertrophic obstructive cardiomyopathy (HOCM) who remain symptomatic despite optimal medical therapy. The procedure causes a controlled myocardial infarction of the basal portion of the interventricular septum by the injection of absolute alcohol with the aim of reducing LVOT obstruction and improving the patient's hemodynamics and symptoms. Numerous observations have demonstrated the efficacy and safety of the procedure, making it a valid alternative to surgical myectomy. In particular, the success of alcohol septal ablation depends on appropriate patient selection and the experience of the institution where the procedure is performed. In this review, we summarize the current evidence on alcohol septal ablation and highlight the importance of a multidisciplinary approach involving a team of clinical and interventional cardiologists and cardiac surgeons with high expertise in the management of HOCM patients-the Cardiomyopathy Team.

Septal myectomy or alcohol ablation for hypertrophic cardiomyopathy: A nationwide inpatient sample (NIS) database analysis

BACKGROUND

Comparison of the real-world cohort on the relative safety of alcohol septal ablation (ASA) vs. septal myectomy (SM) for the management of hypertrophic cardiomyopathy (HCM) has been lacking.

METHODS

The National Inpatient Sample (NIS) (2012-2019) was used to select all cases of HCM. The safety of ASA vs. SM was compared using a one:many propensity score matched (PSM) analysis. Adjusted odds ratios (aOR) for mortality and other in-hospital complications were computed.

RESULTS

A total of 6208 HCM patients (ASA 3106 vs. SM 3102) were included using a PSM analysis. Post-procedural bleeding (aOR 0.18, 95 % CI 0.11-0.32, p < 0.0001) and the need for an intra-aortic balloon pump (aOR 0.51, 95 % CI, 0.28-0.96, p = 0.037) were significantly lower while permanent pacemaker (PPM) implantation was significantly higher in ASA group as compared with SM group (aOR 1.72, 95 % CI, 1.43-2.06, p < 0.0001). The total in-hospital mean adjusted cost and length of stay were also significantly lower in the ASA group. However, there were no significant differences in adjusted odds of all-cause mortality (aOR 0.91, 95 % CI 0.62-1.33, p = 0.61), stroke (aOR 0.91, 95 % CI, 0.59-1.4, p = 0.66), and major bleeding (aOR 1.0, 95 % CI 7.8-1.29, p = 0.99) between the two comparison groups.

CONCLUSION

In patients with hypertrophic cardiomyopathy, alcohol septal ablation appears to be an acceptable alternative to septal myectomy due to a lower risk of post-procedural bleeding and the need for an intra-aortic balloon pump. However, ASA confers a higher risk of PPM placement.

Review of Contemporary Invasive Treatment Approaches and Critical Appraisal of Guidelines on Hypertrophic Obstructive Cardiomyopathy: State-of-the-Art Review

BACKGROUND

Hypertrophic obstructive cardiomyopathy (HOCM) is a heterogeneous disease with different clinical presentations, albeit producing similar dismal long-term outcomes if left untreated. Several approaches are available for the treatment of HOCM; e.g., alcohol septal ablation (ASA) and surgical myectomy (SM). The objectives of the current review were to (1) discuss the place of the standard invasive treatment modalities (ASA and SM) for HOCM; (2) summarize and compare novel techniques for the management of HOCM; (3) analyze current guidelines addressing HOCM management; and (4) offer suggestions for the treatment of complex HOCM presentations.

METHODS

We searched the literature and attempted to gather the most relevant and impactful available evidence on ASA, SM, and other invasive means of treatment of HOCM. The literature search yielded thousands of results, and 103 significant publications were ultimately included.

RESULTS

We critically analyzed available guidelines and provided context in the setting of patient selection for standard and novel treatment modalities. This review offers the most comprehensive analysis to-date of available invasive treatments for HOCM. These include the standard treatments, SM and ASA, as well as novel treatments such as dual-chamber pacing and radiofrequency catheter ablation. We also account for complex pathoanatomic presentations and current guidelines to offer suggestions for tailored care of patients with HOCM. Finally, we consider promising future therapies for HOCM.

CONCLUSIONS

HOCM is a heterogeneous disease associated with poor outcomes if left untreated. Several strategies for treatment of HOCM are available but patient selection for the procedure is crucial.

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.