DILATED CORONARY SINUS IN A DOG WITH PERSISTENT LEFT CRANIAL VENA-CAVA

This paper describes the electrocardiographic, echocardiographic (two- dimensional, M-mode, contrast and Doppler) and non-selective angiocard iographic features in a 3 year old female Beagle with dilated coronary sinus due to persistent left cranial vena cava. Negative P waves in l eads III and aVR and a positive P wave in lead aVL were seen, Echocard iographically, a hipoechoic circular structure was seen between the le ft atrium and the pericardium in the area where the coronary sinus is located, A velocity pattern with two peaks was obtained, one systolic with velocity = 0.44 +/- 0.05 m/sec and the other diastolic with veloc ity = 0.27 +/- 0.01 m/sec, By M-mode echocardiography, at level of the aorta and the left atrium, a linear structure was identified between the left atrium and the pericardium; this structure was characterized by phasic movements of the anterior wall during the cardiac cycle, Fol lowing a left cephalic vein injection of saline, bubbles were seen wit hin the coronary sinus; when saline was injected into the right cephal ic vein, bubbles were also seen within the coronary sinus and right at rium and ventricle, Non-selective angiocardiography confirmed a dilate d coronary sinus with persistent left cranial vena cava, The right cra nial vena cava was absent, The dog was clinically normal and the unusu al vessel was an incidental finding.