Abstract 3572: Usefulness of Three-Dimensional Echocardiographic Quantification during Percutaneous Alcohol Septal Ablation for Hypertrophic Obstructive Cardiomyopathy
Background: Previous studies have shown that intracoronary myocardial contrast echocardi-ography (MCE) during alcohol septal ablation (ASA) in patients with hypertrophic obstructive cardiomyopathy (HOCM) provides useful information for target vessel selection. The purpose of this study was to test the usefulness of quantitative assessment of septal infarction risk territory demonstrated by MCE using three-dimensional echocardiography (3DE) during ASA.
Methods: We examined nine patients with HOCM who received ASA therapy. Maximum velocity across left ventricular outflow tract (LVOT) was evaluated by conventional Doppler echocardi-ography at baseline and after ASA. Intracoronary MCE was performed before alcohol injection and the image of MCE risk territory was acquired with two-dimensional echocardiography (2DE) and 3DE (Phillips 7500, X4 probe). The MCE risk area derived from 2DE was calculated by planimetry and the volume from 3DE was calculated by three-dimensional volumetric method (TomTec). Plasma total creatine kinase (CK) and troponin I (TnI) were measured at baseline and serially 36 hours.
Results: Clinical and hemodynamic success was achieved in all but one patient following recurrence of LVOT gradient. The LVOT gradient decreased from 53.8 ± 20.7 to 17.6 ± 10.2 mmHg (p = 0.0001). The mean values of the MCE risk area measured by 2DE and volume by 3DE were 1.5 ± 0.8 cm2 and 5.1 ±2.7 ml, respectively. The volume of MCE risk territory correlated better with the peak release of cardiac biomarkers than did the area (with peak CK; r = 0.93, p = 0.0003 vs. r = 0.86, p = 0.003; with peak TnI: r = 0.91, p = 0.0005 vs. r = 0.84, p = 0.004).
Conclusions: The measurement of MCE risk volume assessed by 3DE-MCE during ASA may be an accurate predictor of the infarct size that follows alcohol injection, further suggesting the potential to predict the outcome or complication after ASA.