Results of Ten-Year Follow-Up of Alcohol Septal Ablation in Patients with Obstructive Hypertrophic Cardiomyopathy

Canadian Cardiovascular Society Clinical Practice Update on Contemporary Management of the Patient With Hypertrophic Cardiomyopathy

Numerous guidelines on the diagnosis and management of hypertrophic cardiomyopathy (HCM) have been published, by learned societies, over the past decade. Although helpful they are often long and less adapted to nonexperts. This writing panel was challenged to produce a document that grew as much from years of practical experience as it did from the peer-reviewed literature. As such, rather than produce yet another set of guidelines, we aim herein to deliver a concentrate of our own experiential learning and distill for the reader the essence of effective and appropriate HCM care. This Clinical Practice Update on HCM is therefore aimed at general cardiologists and other cardiovascular practitioners rather than for HCM specialists. We set the stage with a description of the condition and its clinical presentation, discuss the central importance of "obstruction" and how to look for it, review the role of cardiac magnetic resonance imaging, reflect on the appropriate use of genetic testing, review the treatment options for symptomatic HCM-crucially including cardiac myosin inhibitors, and deal concisely with practical issues surrounding risk assessment for sudden cardiac death, and management of the end-stage HCM patient. Uniquely, we have captured the pediatric experience on our panel to discuss appropriate differences in the management of younger patients with HCM. We ask the reader to remember that this document represents expert consensus opinion rather than dogma and to use their best judgement when dealing with the HCM patient in front of them.

Interventions in Hypertrophic Obstructive Cardiomyopathy

Obstructive hypertrophic cardiomyopathy is the most common genetically transmitted cardiomyopathy that is associated with significant morbidity and mortality. Despite contemporary treatments and interventions, the management of patients with obstructive hypertrophic cardiomyopathy remains poorly defined compared with other branches of cardiology. In this review, we discuss established and novel therapeutic interventions in patients with obstructive hypertrophic cardiomyopathy with a focus on percutaneous and surgical strategies including surgical myectomy, mitral valve repair or replacement, percutaneous alcohol septal ablation, pacemaker and cardioverter-defibrillator implantation, septal embolization, radiofrequency endocardial catheter ablation, and percutaneous intramyocardial septal radiofrequency ablation.

Treatment Strategies for Hypertrophic Cardiomyopathy: Alcohol Septal Ablation and Procedural Step-by-Step Technique

Alcohol septal ablation (ASA) is a well-established procedure for septal reduction therapy in patients with obstructive hypertrophic cardiomyopathy, significant at rest or provocable outflow tract gradients, and medically refractory symptoms. This percutaneous approach to relief of obstruction and eventual cardiac remodeling involves the infusion of a small quantity of ethanol into an appropriately targeted septal artery that is feeding the basal septum to create an iatrogenic and controlled focal infarction. Early akinesia is followed by subsequent thinning and remodeling, which widens the outflow tract, reducing or eliminating the obstruction. Historically, the use of ASA was reserved primarily for high-risk surgical candidates; however, more contemporary data suggest similar outcomes in the short-term and long-term safety of the procedure and overall effectiveness in relieving obstructive symptoms when it is performed in broader populations at experienced centers. Therefore, the current guidelines published in 2020 support ASA as a class 1 indication, similar to its open-heart surgical counterpart, surgical myectomy, when no concomitant significant coronary or valve surgical indication exists. This article summarizes contemporary management of patients with hypertrophic cardiomyopathy who were selected for ASA and details procedural methods and outcomes.

Alcohol Septal Ablation: An Option on the Rise in Hypertrophic Obstructive Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) can cause symptoms due to the obstruction of the left ventricle outflow tract (LVOT). Although pharmacological therapy is the first step for treating this condition, many patients do not fully respond to the treatment, and an invasive approach is required to manage symptoms. Septal reduction therapies include septal myectomy (SM) and alcohol septal ablation (ASA). ASA consists of a selective infusion of high-grade alcohol into a septal branch supplying the basal interventricular septum to create an iatrogenic infarction with the aim of reducing LVOT obstruction. Currently, SM and ASA have the same level of indication; however, ASA is normally reserved for patients of advanced age, with comorbidities or when the surgical approach is not feasible. Recent data suggests that there are no differences in short- and long-term all-cause mortality, cardiovascular mortality and sudden cardiac death between ASA and SM. Despite the greater experience and refinement of the technique gained in recent years, the most common complication continues to be complete atrio-ventricular block, requiring a permanent pacemaker. Septal reduction therapies should be performed in experienced centres with comprehensive programs.

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.