Hucker William J. author Ripplinger Crystal M. author Fleming Christine P. author Columbia University. Electrical Engineering Fedorov Vadim V. author Rollins Andrew M. author Efimov Igor R. author Columbia University. Electrical Engineering originator text Articles 2008 English The development of systems physiology is hampered by the limited ability to relate tissue structure and function in intact organs in vivo or in vitro. Here, we show the application of a bimodal biophotonic imaging approach that employs optical coherence tomography and fluorescent imaging to investigate the structure-function relationship at the tissue level in the heart. Reconstruction of cardiac excitation and structure was limited by the depth penetration of bimodal imaging to ∼2mm in atrial tissue, and ∼1mm in ventricular myocardium. The subcellular resolution of optical coherence tomography clearly demonstrated that microscopic fiber orientation governs the pattern of wave propagation in functionally characterized rabbit sinoatrial and atrioventricular nodal preparations and revealed structural heterogeneities contributing to ventricular arrhythmias. The combination of this bimodal biophotonic imaging approach with histology and/or immunohistochemistry can span multiple scales of resolution for the investigation of the molecular and structural determinants of intact tissue physiology. Medical imaging and radiology 13 5 054012-1 054012-7 2008-09 http://dx.doi.org/10.1117/1.2975826 http://hdl.handle.net/10022/AC:P:15235 NNC NNC 2012-11-08 14:26:31 -0500 2012-11-08 14:49:24 -0500 9237 eng