Reduction of left ventricular mass, left atrial size, and N-terminal pro-B-type natriuretic peptide level following alcohol septal ablation in patients with hypertrophic obstructive cardiomyopathy.

Abstract

Alcohol septal ablation (ASA) is an alternative to surgical treatment in patients with hypertrophic obstructive cardiomyopathy (HOCM). Through alcohol-induced necrosis, ASA leads to an increase in left ventricular outflow tract (LVOT) diameter and a decrease in LVOT pressure gradient. We sought to assess the effect of ASA on left ventricular (LV) wall thickness and mass, left atrial (LA) size, and N-terminal pro-B-type natriuretic peptide (NT-proBNP) level. The study cohort consisted of 50 patients with HOCM (30 in the ASA group, 20 in the optimal pharmacotherapy group [OPG]). Transthoracic echocardiography (TTE), cardiac magnetic resonance (CMR), and NT-proBNP level analysis were performed at baseline and at six months. All parameters are presented as means. In the ASA group, the maximal LVOT pressure gradient decreased from 122.7 to 54.8 mmHg directly after ASA and to 37.2 mmHg after a further six months (p < 0.0001). The NT-proBNP level decreased from 2174.4 to 1103.4 pg/mL (p < 0.001). On TTE, the interventricular septum (IVS) thickness decreased to from 23.6 to 19.4 mm (p < 0.0001) and the lateral wall (LW) thickness decreased from 15.9 to 14.2 mm (p < 0.007). On CMR, basal IVS thickness decreased from 23.7 to 18.0 mm (p < 0.0001) and the LW thickness decreased from 13.2 to 12.2 mm (p = 0.02). IVS mass reduced from 108.9 to 91.5 g (-16%; p < 0.001). All of the above parameters remained unchanged in the OPG. Successful ASA reduces LV hypertrophy and improves parameters of the LV overload, resulting in LV wall hy-pertrophy regression, and LA size and NT-proBNP level reduction. The above parameters may be as useful in assessing the efficacy of ASA as the LVOT gradient itself.