Pericardioscopic imaging findings in cadaveric dogs: comparison of an apical pericardial window and sub-phrenic pericardectomy.

Objective: To compare the pericardioscopic cardiovascular anatomy visible between apical pericardial window (PW) and sub-phrenic pericardectomy (SPP).

Study Design: Experimental study.

Animals: Canine cadavers (n = 5).

Methods: Thoracoscopy was performed using a transdiaphragmatic subxyphoid and right and left intercostal portals. A 4 cm × 4 cm apical PW was created with endoscopic scissors. The intra-pericardiac structures were then pericardioscopically assessed using a subjective ordinal scale (0: not visible, 1: <50% seen, 2: >50% seen) before SPP. Assessment was repeated after SPP.

Results: An apical PW provided limited access to the cardiac structures, with only the right ventricle >50% visible in all cadavers. The right atrium, right auricle, left ventricle, right coronary artery, and interventricular paraconal branch of the left coronary artery were observed but were typically <50% visible after apical PW. The left atrium and auricle, and heart base could not be consistently seen through an apical PW. Sub-phrenic pericardectomy significantly improved observation of all intrapericardiac structures assessed, except for the right atrium and right ventricle.

Conclusions: PW centered over the cardiac apex limits evaluation of the pericardial space during pericardioscopy compared to SPP in cadaveric dogs.