Trajectory of coronary motion and its significance in robotic motion cancellation

Objectives: To characterize remaining coronary artery motion of beating pig hearts after stabilization with an ?Octopus? using an optical remote analysis technique. Methods: Three pigs (40, 60 and 65 kg) underwent full sternotomy after receiving general anesthesia. An 8-bit high speed black and white video camera (50 frames/s) coupled with a laser sensor (60 m resolution) were used to capture heart wall motion in all three dimensions. Dopamine infusion was used to deliberately modulate cardiac contractility. Synchronized ECG, blood pressure, airway pressure and video data of the region around the first branching point of the left anterior descending (LAD) coronary artery after Octopus stabilization were captured for stretches of 8 s each. Several sequences of the same region were captured over a period of several minutes. Computerized off-line analysis allowed us to perform minute characterization of the heart wall motion. Results: The movement of the points of interest on the LAD ranged from 0.22 to 0.81 mm in the lateral plane (x/y-axis) and 0.5?2.6 mm out of the plane (z-axis). Fast excursions (<50 m/s in the lateral plane) occurred corresponding to the QRS complex and the T wave; while slow excursion phases (