Persistent left cranial vena cava was found in a three-year-old male Doberman Pinscher dog affected with the vena caval syndrome of canine heartworm disease. Surgical removal of heartworms from this dog through the jugular vein was unsuccessful due to the unusual course of the cranial vena cave opening into the right atrium. Electrocardiogram, roentgenogram, and cardioangiogram were described of this dog. Autopsy showed no remnants of the right cranial vena cava or any other detectable cardiovascular anomaly.
