Mapping the human pulmonary venoatrial junction with optical coherence tomography

Abstract

Imaging guidance provided by optical coherence tomography (OCT) could improve the outcomes of atrial fibrillation (AF) ablation by providing detailed structural information of the pulmonary veins, which are critical targets during ablation. In this study, stitched volumetric OCT images of venoatrial junctions from post-mortem human hearts were acquired and compared to histology. Image features corresponding to venous media and myocardial sleeves, as well as fiber orientation and fibrosis, were identified and found to vary between veins. Imaging of detailed tissue architecture could improve understanding of the AF structural substrate within the pulmonary veins and assist the guidance of ablation procedures.

Imaging of subendocardial adipose tissue and fiber orientation distributions in the human left atrium using optical coherence tomography

“…Endocardial thickness and composition, distributions of adipose tissue, and fiber directionality were visible within OCT imaging data of the human left atria. Endocardial thickness varied over the left atrium, and varying densities and compositions of connective tissue within the endocardium could be observed in OCT as different layers and variations in intensity, as has been described previously . Endocardial thickness was typically thinner near the septum, which allowed the septal region to be particularly feature‐rich within the imaging depth of OCT. Adipose tissue and fiber orientation were often visible within the septal region.…”

“…While this study focused on adipose tissue and fiber orientation, it is also possible for OCT to provide features corresponding to fibrosis, as has been described in prior OCT studies . Previously, OCT has also been used to describe myofiber orientation within animal models, ex vivo, with some studies incorporating optical clearing or serial sectioning methods to improve imaging depth.…”

“…Various tissue types in the human heart, including endocardial connective tissues, myocardium, adipose tissue, and fibrotic tissue have been identified with OCT . OCT has been shown to provide detailed imaging of interstitial collagen patterns within the myocardium . However, these studies focused on small regions of tissue, which provide an incomprehensive view of the utility of OCT imaging throughout a cardiac chamber.…”

“…Various tissue types in the human heart, including endocardial connective tissues, myocardium, adipose tissue, and fibrotic tissue have been identified with OCT. [7][8][9][10] OCT has been shown to provide detailed imaging of interstitial collagen patterns within the myocardium. 11 However, these studies focused on small regions of tissue, which provide an incomprehensive view of the utility of OCT imaging throughout a cardiac chamber. Therefore, the objective of this study was to provide OCT data throughout the human left atrium, as imaged from the endocardium, with particular focus on the distribution of subendocardial adipose tissue and fiber orientation.…”

Characterization of the human myocardium by optical coherence tomography

“…Recently, OCT imaging of the human heart has also been explored, identifying features of the cardiac conduction system , endocardial scar, fibrosis and adipose tissue . Comprehensive OCT imaging of the human pulmonary veins has visualized collagen fibers in the venous myocardial sleeves, including varying organization among different veins . Finally, OCT‐integrated catheters have been developed for the monitoring of lesion formation during ablation procedures for atrial fibrillation, with some demonstrations in vivo .…”