Biplane transesophageal echocardiography in the normal cat

Eight healthy, adult cats were examined with biplane transesophageal echocardiography (TEE). Cats were sedated with a combination of diazepam and propofol and were examined using a 5 mm x 80 cm pediatric biplane TEE probe. Consistent images were obtained at three imaging depths within the esophagus. The caudal position provided satisfactory short-axis images of the left ventricle and heart base. The middle position provided the best long-axis views of the left atrium, left ventricle, and aorta and allowed Doppler examination of transmitral left ventricular inflow. The cranial position provided satisfactory imaging of the aorta and pulmonary artery and allowed Doppler examination of right ventricular and left ventricular outflow. Biplane TEE provides an additional method of imaging the feline heart which is complimentary to other imaging techniques and the images obtained were similar to those reported for dogs. Although TEE offers a slight advantage over transthorcic imaging for Doppler examination, the quality of the images of heart base structures was not as consistently superior to transthoracic images in cats as reported in dogs.