Use of novel nonfluoroscopic three-dimensional electroanatomic mapping system to monitor and analyze heart surgery in animal models

Background: The new method of three-dimensional (3D) electroanatomic mapping was presented as an important tool for cardiac imaging and intervention. We present herein the first use of this technology for the monitoring, analysis, and development of cardiac surgery at the preclinical stage. Methods: The method is based on utilizing a locatable catheter connected to an endocardial mapping and navigating system, to accurately establish the location and orientation of the tip of the mapping catheter and simultaneously record its local electrogram. The 3D geometry of the beating cardiac chamber is reconstructed in real time. The system was tested on six goats that underwent dynamic cardiomyoplasty. Two maps of each animal were performed: preoperative and postoperative during the stimulation protocol of the skeletal muscle. Results: The electroanatomic mapping system provided detailed maps of the left ventricle during the stimulation protocol, which demonstrated a striking geometric difference between the assisted and the unassisted beats. These geometric changes are best described by referring to left ventricular long-axis movements (22.3 ± 3.8° vs 3.4 ± 1.6°, p < 0.001), center-of-mass movements (10.4 ± 3.0 mm vs 3.9 ± 1.6 mm, p < 0.005), and the changes in upward movement viewed along the base (7.9 ± 1.9 mm vs 3.6 ± 1.7 mm, p < 0.01), middle (13.8 ± 4.0 mm vs 7.3 ± 1.8 mm, p < 0.005), and the apex of the heart (28.1 ± 4.5 vs 5.3 ± 2.3 mm, p < 0.001) [mean ± SD]. Conclusions: The 3D electroanatomic mapping system allows detailed reconstruction of the left ventricular geometry and a clear view of the difference between the assisted and the unassisted beats. This novel monitoring system may serve as an important tool for the analysis and development of new techniques in cardiac surgery.