Yoo J, Ko J, Yoon H, Eom K, Kim J.J Vet Med Sci. 2020 May 15. doi: 10.1292/jvms.19-0518. Online ahead of print.PMID: 32418943 Free article.
A seven-month-old cat was referred for evaluation of exercise intolerance and open-mouth breathing. Based on ultrasonographic examination, caudal vena cava (CVC) aneurysm associated with right congestive heart failure resulting from congenital heart disease was diagnosed. Conservative treatment for alleviating pulmonary hypertension mildly improved the clinical signs and decreased the heart size and CVC aneurysm diameter. However, the improvements were transient and four months after initiating therapy, the cat developed dyspnea and uncontrollable seizures and was euthanized.
Fig. 1. (A) Right lateral and (B) ventrodorsal radiograph of a seven-month-old Korean shorthair cat. Radiographs demonstrate severe cardiomegaly and pruning of the peripheral pulmonary artery with increased radiolucency of the lung field. A tubular soft-tissue density is visible on the caudoventral thorax extending from the heart to the diaphragm. To make a reasonable comparison before and after the medication treatment, the ratio of the diameter of the CVC to the length of 5th thoracic vertebral body (CVC:V) was measured. On this radiograph, the CVC:V ratio was 6.82. Dotted line, diameter of the CVC; solid line, length of 5th thoracic vertebral body.
Fig. 2. Right parasternal long axis, five-chamber view echocardiogram. (A) Two-dimensional echocardiography shows a 3-mm perimembranous ventricular septal defect. The right ventricular wall is markedly hypertrophied. (B) The color-Doppler demonstrates the turbulent flow across the left ventricular outflow tract and the right ventricle. Ao, aorta; LVW, left ventricular wall; RVW, right ventricular wall; IVS, interventricular septum; LA, left atrium. Asterisk (*), ventricular septal defect.
Fig. 3. Right parasternal four-chamber and left apical four-chamber view echocardiogram. (A) Hypertrophied right ventricular wall and interventricular septum is noted. Additionally, there is a leftward displacement of the atrial septum which indicates elevated right atrial pressure. The left atrium is not well identified due to compression. (B) After microbubble injection, the bubbles cross the defect from the right ventricle to the left ventricle. LVW, left ventricular wall; RVW, right ventricular wall; RA, right atrium; LA, left atrium; IVS, interventricular septum. Asterisk (*), ventricular septal defect.
Fig. 4. Ultrasound images obtained from right caudal thorax with the left-hand side of the image directed cranially. A 3 cm large tortuous vessel is seen on the caudal thorax that was identified as CVC since it is connected to the right atrium cranially and to the hepatic veins caudally. A small amount of pleural effusion is seen around the field. L, liver; CVC, caudal vena cava.
Fig. 5. Right lateral (A) and ventrodorsal (B) thoracic radiographs following 1 month after starting medication. Reduction of the CVC was noted, as compared to a previous thoracic radiograph. On this radiograph, the CVC:V ratio was 4.09. Dotted line, diameter of the CVC; solid line, length of 5th thoracic vertebral body.