Cyanoacrylate for Septal Ablation in Hypertrophic Cardiomyopathy

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.

Single Center Experience of Percutaneous Septal Ablation in Patients With Hypertrophic Cardiomyopathy With A Novel Agent: Polidocanol

Septal reduction therapy is recommended in patients with obstructive hypertrophic cardiomyopathy (HCM) who remain symptomatic under maximally tolerated optimal medical treatment. Alcohol septal ablation is a favorable option, especially in patients with high surgical risk or who refuse surgery. Alcohol; causes scar-related ventricular arrhythmias and advanced heart blocks more frequently than surgical myectomy. Therefore, novel, safer agents are required for percutaneous septal ablation therapy. All the patients who underwent percutaneous septal ablation between January 2017 and June 2021 with polidocanol because of ongoing symptoms related to HCM despite maximally tolerated medical treatment were enrolled. Data were obtained retrospectively from the hospital electronic database. A total of 28 patients were included. Median age was 61 years (43.5-67), and 19 (67.8%) patients were male. Most of the patients underwent index procedures; however, only 2 cases had history of previous septal ablation. Median follow-up was 3.5 months (0.25 to 12.25). Median left ventricular outflow tract (LVOT) gradient at rest was 68.5 (37-80) mm Hg, and after Valsalva maneuver median LVOT gradient was 95.5 (75-125) mm Hg. Median volume of polidocanol used in procedures was 2 (2-3.37) ml, and mean procedure time was 28.1 ± 2.5 minutes. LVOT gradient invasively measured was significantly reduced (mean 76.5 mm Hg vs mean 30 mm Hg; p <0.001) immediately after the septal ablation. Conduction defects developed in 18 patients (64.2%); however, de novo permanent cardiac implantable electronic device implantation was required in only 4 (14.3%) cases. Leakage of polidocanol and mortality did not occur in any cases. Pericardial effusion developed in only 1 case, and it resolved with medical treatment. After mean 3.5 months follow-up, both LVOT gradient and New York Heart Association functional class parameters were better than baseline values. In conclusion, polidocanol is a safe and effective agent for septal ablation in patients with HCM. Outcomes and complication rates are similar with alcohol septal ablation.

Septal reduction therapy using nonalcohol agent in hypertrophic obstructive cardiomyopathy: Single center experience

AIMS

Percutaneous septal reduction therapy by either alcohol or nonalcohol agents is an alternative approach to surgery in drug-refractory symptomatic patients with hypertrophic obstructive cardiomyopathy (HOCM). Nonalcohol agents have some advantages and disadvantages over alcohol during the procedure. Nowadays, a novel non-alcohol agent, named as Ethylene-vinyl alcohol (EVOH) copolymer (Onyx^® and Squid^® ), is used during septal ablation. Thus, in this study, we aimed to evaluate both acute and long-term efficacy and safety profile of EVOH during septal ablation in HOCM.

METHODS AND RESULTS

A total of 25 patients (52% female; mean age: 55.8 ± 17.1 years) with symptomatic HOCM were enrolled in the study. All subjects underwent clinical and laboratory assessment before and after the procedure. Peak left ventricular outflow tract (LVOT) gradient was significantly reduced just after the procedure (68 vs. 20 mmHg; P < 0.001). Peak serum creatine kinase-myocardial band and troponin I levels were 112 (35-282) ng/ml and 11 (4-93) ng/ml. EVOH embolization to diagonal artery was observed in 1 patient (4%) and the complete atrioventricular block was noted in 2 (8%) patients. During the 12-month follow-up, there was no mortality. There was a significant improvement in New York Heart Association functional class of the subjects P < 0.001). Both interventricular septum thickness and LVOT gradient showed a significant reduction during follow-up (P < 0.05). However, there was no reduction in the LVOT gradient of 3 patients (12%).

CONCLUSIONS

In conclusion, our small-sized preliminary study results showed that septal reduction therapy using EVOH is an effective alternative option in reducing symptoms and LVOT gradient in HOCM.

Septal Ablation for Hypertrophic Obstructive Cardiomyopathy: Transcoronary and Endocardial Approach

Septal reduction therapy is the gold standard treatment method for symptomatic, hypertrophic obstructive cardiomyopathy. Although surgical myectomy is a well-established and effective technique with decades of experience in its application, use of transcoronary alcohol septal ablation has increased precipitously owing to the less-invasive nature of the procedure. Moreover, endocardial septal ablation therapy is a relatively newly defined modality, and outcomes of the procedure are not clearly elucidated yet. In this review, we aimed to present nonsurgical septal reduction approaches in patients with hypertrophic obstructive cardiomyopathy.

Glue septal ablation: A promising alternative to alcohol septal ablation

Hypertrophic cardiomyopathy (HCM) is defined as myocardial hypertrophy in the absence of another cardiac or systemic disease capable of producing the magnitude of present hypertrophy. In about 70% of patients with HCM, there is left ventricular outflow tract (LVOT) obstruction (LVOTO) and this is known as obstructive type of hypertrophic cardiomyopathy (HOCM). Cases refractory to medical treatment have had two options either surgical septal myectomy or alcohol septal ablation (ASA) to alleviate LVOT gradient. ASA may cause some life-threatening complications including conduction disturbances and complete heart block, hemodynamic compromise, ventricular arrhythmias, distant and massive myocardial necrosis. Glue septal ablation (GSA) is a promising technique for the treatment of HOCM. Glue seems to be superior to alcohol due to some intrinsic advantageous properties of glue such as immediate polymerization which prevents the leak into the left anterior descending coronary artery and it is particularly useful in patients with collaterals to the right coronary artery in whom alcohol ablation is contraindicated. In our experience, GSA is effective and also a safe technique without significant complications. GSA decreases LVOT gradient immediately after the procedure and this reduction persists during 12 months of follow-up. It improves New York Heart Association functional capacity and decrease interventricular septal wall thickness. Further studies are needed in order to assess the long-term efficacy and safety of this technique.

Intervention in HCM: patient selection, procedural approach and emerging techniques in alcohol septal ablation

Hypertrophic cardiomyopathy (HCM) is a highly heterogeneous disease with varied patterns of hypertrophy. Basal septal hypertrophy and systolic anterior motion (SAM) of the mitral valve (MV) are the key pathophysiological components to left ventricular outflow tract (LVOT) obstruction in HCM. LVOT is associated with higher morbidity and mortality in patients with HCM. Percutaneous septal reduction therapy with alcohol septal ablation (ASA) can lead to a significant improvement in left ventricle haemodynamics, patient symptoms and perhaps prognosis. ASA delivers pure alcohol to an area of myocardium via septal coronary arteries; this creates damage to tissue akin to a myocardial infarction. The basal septal myocardium involved in SAM-septal contact is the target for this iatrogenic infarct. Appropriate patient selection and accurate delivery of alcohol are critical to safe and effective ASA. Securing the correct diagnosis and ensuring suitable cardiac anatomy are essential before considering ASA. Pre-procedural planning and intra-procedural imaging guidance are important to delivering precise damage to the desired area. The procedure is performed worldwide and is generally safe; the need for a pacemaker is the most prominent complication. It is successful in the majority of patients but room for improvement exists. New techniques have been proposed to perform percutaneous septal reduction. We present a review of the relevant pathophysiology, current methods and a summary of available evidence for ASA. We also provide a glimpse into emerging techniques to deliver percutaneous septal reduction therapy.

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 the Treatment of Hypertrophic Obstructive Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is an inherited myocardial disorder characterised by left ventricular hypertrophy. A subgroup of patients develops limiting symptoms in association with left ventricular outflow tract obstruction (LVOTO). Current international guidelines recommend that symptomatic patients are initially treated by alleviating exacerbating factors and negatively inotropic medication. Drug-refractory symptoms require a comprehensive evaluation of the mechanism of LVOTO and review by a multidisciplinary team to consider the relative merits of myectomy, alcohol septal ablation (ASA) and pacing. This article provides a brief overview of HCM and the pathophysiology of LVOTO, and reviews the use of ASA in patients with drug-refractory symptoms secondary to LVOTO.