Predictors of procedural failure of alcohol septal ablation in patients with hypertrophic obstructive cardiomyopathy: data from a single-center retrospective study

Background: Comparative studies demonstrate commensurate longterm survival rates after surgical myectomy and alcohol septal ablation in patients with hypertrophic obstructive cardiomyopathy, although endovascular interventions are associated with a less pronounced decrease in the obstruction gradient and an increased rate of repeat procedures. Considering the proven interrelations between residual pressure gradient and long-term survival, identification of factors affecting the hemodynamic efficacy of alcohol septal ablation is of particular clinical importance for improving selection criteria for patient and optimizing therapeutic оutcomes. Objective: The study was aimed at assessment of short-term results of alcohol septal ablation and the detection of predictors for procedural failure of the intervention. Methods: This retrospective single-center study included 71 patients with hypertrophic obstructive cardiomyopathy who underwent septal alcohol ablation. The criterion for procedural failure of the intervention was considered to be the retention of the residual pressure gradient in the left ventricular outflow tract of ≥30 mm Hg at rest and/or the provoked gradient of ≥50 mm Hg at the time of patient discharge. The primary endpoint was predictors of technical failure. Secondary endpoints included technical failure, in-hospital complications, and echocardiographic parameters. Results: The rate of procedural failure was 26.8 % (19/71). In the postoperative period, a significant decrease in the pressure gradient in the left ventricular outflow tract was from 77 mm Hg (64, 95) to 27 mm Hg (19, 45) (p < 0.001). There were no cases of acute cerebrovascular accident and hospital mortality. Implantation of a permanent pacemaker was required in 4.3 % of cases. Independent predictors of procedural failure of alcohol septal ablation included initial values of left ventricular endsystolic volume (OR 1.08, 95 % CI 1.02–1.16, p = 0.023) and left ventricular end-diastolic volume (OR 1.10, 95 % CI 1.04–1.19, p = 0.019), as well as left ventricular posterior wall thickness (OR 1.40, 95 % CI 1.06–1.96, p = 0.030). Conclusion: This study presents the experience of alcohol septal ablation in a single center. Procedural success of the intervention was significantly associated with initial left ventricular end-systolic volume, initial left ventricular end-diastolic volume, and left ventricular posterior wall thickness.