Background: Cardiovascular disease often manifests as a combination of pathological electrical and structural heart remodeling. The relationship between mechanics and electrophysiology is crucial to our understanding of mechanisms of cardiac arrhythmias and the treatment of cardiac disease. While several technologies exist for describing whole-heart electrophysiology, studies of cardiac mechanics are often limited to rhythmic patterns or small sections of tissue. Methods and Results: Here, we present a comprehensive system based on ultrafast three-dimensional (3D) structured light imaging to map surface dynamics of whole-heart cardiac motion. Additionally, we introduce a novel non-rigid motion-tracking algorithm based on an isometry-maximizing optimization framework that forms correspondences between consecutive 3D frames without the use of any fiducial markers. By combining our 3D imaging system with non-rigid surface registration, we are able to measure cardiac surface mechanics at unprecedented spatial and temporal resolution. Conclusions: We demonstrate accurate cardiac deformation at over 200,000 surface points of a rabbit heart recorded at 200 frames per second and validate our results on highly contrasting heart motions during normal sinus rhythm, ventricular pacing, and ventricular fibrillation.
- cardiac mechanics
- Copyright © 2012, American Journal of Physiology - Heart and Circulatory Physiology