Abstract:

This paper describes the measurement of a data set used to create a three-dimensional (3-D) parametric model of atrial anatomy. A short introduction to porcine and human atrial anatomy is given and important anatomical differences are noted. The data acquisition techniques are described. A pig heart was arrested in diastole and perfusion fixed in-situ at physiological pressures with the chest open but the pericardium intact, then excised, cast and mounted. A six-degree-of-freedom measurement arm was used to measure three-dimensional epicardial surface geometry and fiber angles. An epicardial surface model was created using a computer aided design (CAD ) software program for reverse engineering. The model was used to direct the dissection of the heart into small tissue blocks from which endocardial fiber angles and wall thicknesses were measured. Tissue blocks were then cryo-sectioned for histology and the identification of conducting system structures. Figures and images illustrate the resulting surface model, the acquired fiber angles and wall thickness. This preliminary work provides a foundation for building a three-dimensional anatomically detailed model suitable as a mesh for computational analysis of atrial mechanics and electrophysiology.