Septal alcohol ablation in patients with hypertrophic cardiomyopathy and left ventricular outflow tract obstruction

BACKGROUND: Hypertrophic cardiomyopathy is a primarily genetically determined myocardial disease characterized by pronounced, often asymmetric, myocardial hypertrophy that results in diastolic dysfunction and left ventricular outflow tract obstruction. Septal alcohol ablation is a contemporary, minimally invasive interventional approach to the treatment of this condition.

AIM: To evaluate the effectiveness of septal alcohol ablation and the progression of heart failure in patients following the procedure.

MATERIALS AND METHODS: A single-group, open-label study was conducted to evaluate the outcomes of septal alcohol ablation in patients with hypertrophic cardiomyopathy and left ventricular outflow tract obstruction resistant to pharmacologic therapy. All patients were hospitalized at St. Petersburg City Multidisciplinary Hospital No. 2 between September 2021 and February 2024. Among the 157 patients diagnosed with hypertrophic cardiomyopathy, only 65 met the inclusion criteria. The effectiveness of septal alcohol ablation was assessed based on normalization of the peak pressure gradient in the left ventricular outflow tract and improvement in clinical status, evaluated at hospital discharge, three months’ post-procedure, and during a follow-up visit in February 2024.

RESULTS: A significant reduction in the peak pressure gradient in the left ventricular outflow tract was observed in postoperative patients following septal alcohol ablation — from 81.5 to 21.3 mm Hg (p=0.000001). Interventricular septal thickness decreased from 21.6 to 19.6 mm, left ventricular ejection fraction increased from 63.3 to 65.1%, and left ventricular end-diastolic diameter changed from 42.6 to 42.1 mm (p=0.62). No intraoperative complications such as coronary artery perforation, cardiac tamponade, or access site hematoma were reported. Major cardiovascular events within one year after septal alcohol ablation occurred in 12 patients (18.5%), including 9 cases (13.8%) of heart failure decompensation and 2 cases (3.1%) of myocardial infarction. A statistically significant improvement in New York Heart Association functional class was observed — from class III–IV to class I–II (p=0.0009).

CONCLUSION: Septal alcohol ablation has proven to be an effective and safe treatment modality for obstructive hypertrophic cardiomyopathy, provided that appropriate patient selection is ensured.