DETERMINATION OF ECHOCARDIOGRAPHIC TECHNIQUES FOR CLINICAL ASSESSMENT OF GALAPAGOS (CHELONOIDIS NIGRA COMPLEX) AND ALDABRA (ALDABRACHELYS GIGANTEA) TORTOISES.

The first objective of this study was to establish clinically relevant techniques for cardiac echocardiography in nonanesthetized Galapagos (Chelonoidis nigra complex) and Aldabra (Aldabrachelys gigantea) tortoises. A second objective was to establish guidelines for determining normal echocardiographic anatomy and function in both species. Select echocardiographic reference values were defined for 17 healthy Galapagos tortoises and 27 healthy Aldabra tortoises. Tortoises were either placed in ventral recumbency on an elevated surface or allowed to stand in a natural position by using food distraction. An ultrasound probe was applied in the left or right cervicobrachial window and was positioned in two long axis views to evaluate the three chambers of the heart and the associated great vessels, the presence of pericardial effusion, the atrioventricular inflow velocities, and pulmonic and aortic outflow velocities. The heart rate was 28 ± 12 (median ± SD) bpm, and the ejection fraction was 60.5 ± 10%. Thirty-four of 44 tortoises had identifiable physiologic pericardial effusion. All tortoises were successfully imaged using the techniques described, with consistent identification of cardiac structure and assessment of function. This study provides echocardiographic reference intervals for the clinical evaluation of suspected cardiac disease in captive-managed Galapagos and Aldabra tortoises.