A Carto-based 3D ultrasound system produced modestly smaller left atrial volumes compared to electroanatomic mapping in atrial fibrillation patients (98 vs 109 cm3, P<0.05).
Does a Carto-based 3D ultrasound image system provide more accurate chamber geometries compared to computed tomographic imaging for atrial fibrillation ablation?
A novel 3D ultrasound imaging system provides more accurate cardiac chamber geometries than merged CT imaging, demonstrating feasibility for guiding atrial fibrillation ablation.
Absolute Event Rate: 98% vs 109%
p-value: p=<0.05
BACKGROUND: Multiple factors create discrepancies between electroanatomic maps and merged, preacquired computed tomographic images used in guiding atrial fibrillation ablation. Therefore, a Carto-based 3D ultrasound image system (Biosense Webster Inc) was validated in an animal model and tested in 15 atrial fibrillation patients. METHODS AND RESULTS: Twelve dogs underwent evaluation using a newly developed Carto-based 3D ultrasound system. After fiducial clip markers were percutaneously implanted at critical locations in each cardiac chamber, 3D ultrasound geometries, derived from a family of 2D intracardiac echocardiographic images, were constructed. Point-source error of 3D ultrasound-derived geometries, assessed by actual real-time 2D intracardiac echocardiographic clip sites, was 2.1+/-1.1 mm for atrial and 2.4+/-1.2 mm for ventricular sites. These errors were significantly less than the variance on CartoMerge computed tomographic images (atria: 3.3+/-1.6 mm; ventricles: 4.8+/-2.0 mm; P<0.001 for both). Target ablation at each clip, guided only by 3D ultrasound-derived geometry, resulted in lesions within 1.1+/-1.1 mm of the actual clips. Pulmonary vein ablation guided by 3D ultrasound-derived geometry resulted in circumferential ablative lesions. Mapping in 15 patients produced modestly smaller 3D ultrasound versus electroanatomic map left atrial volumes (98+/-24 cm(3) versus 109+/-25 cm(3), P<0.05). Three-dimensional ultrasound-guided pulmonary vein isolation and linear ablation in these patients were successfully performed with confirmation of pulmonary vein entrance/exit block. CONCLUSIONS: These data demonstrate that 3D ultrasound images seamlessly yield anatomically accurate chamber geometries. Image volumes from the ultrasound system are more accurate than possible with CartoMerge computed tomographic imaging. This clinical study also demonstrates the initial feasibility of this guidance system for ablation in patients with atrial fibrillation.
Okumura et al. (Thu,) conducted a other in Atrial fibrillation (n=15). Carto-based 3D ultrasound image system vs. Electroanatomic mapping and CartoMerge computed tomography was evaluated on Left atrial volume (clinical) and point-source error of geometries (animal model) (p=<0.05). A Carto-based 3D ultrasound system produced modestly smaller left atrial volumes compared to electroanatomic mapping in atrial fibrillation patients (98 vs 109 cm3, P<0.05).