Total anomalous pulmonary venous connection in a mature dog

J Vet Cardiol. 2019 Feb:21:10-17. doi: 10.1016/j.jvc.2018.11.003. Epub 2018 Dec 6.


A 2-year 10-month, male neutered, crossbreed dog presented for evaluation of cyanosis and exercise intolerance. Doppler echocardiography revealed severe dilation of the right atrium and right ventricle with moderate pulmonary hypertension. Right-to-left shunting across a large ostium secundum atrial septal defect was confirmed by contrast echocardiography. Thoracic radiography revealed a vascular pattern together with cardiomegaly. Computed tomography angiography identified an anomalous pulmonary venous connection in which all pulmonary veins, apart from the right middle vein, coalesced into a single, large aneurysmal vein that then drained into the right atrium via the cranial vena cava. The distal opening of the right middle pulmonary vein could not be determined. A presumptive diagnosis of partial anomalous pulmonary venous connection was made. The dog was medically managed with sildenafil (1.5 mg/kg by mouth [PO] every 8 h) and remained clinically stable for 2 months before euthanasia due to worsening exercise intolerance. On postmortem examination, all pulmonary veins, including the right middle vein, were shown to communicate with a single, large central vein. This large vein then connected with the right atrium via the cranial vena cava, consistent with a total anomalous pulmonary venous connection. This case report describes a rare congenital abnormality which has not been previously reported in a mature dog.

Keywords: Congenital cardiovascular defects; Cyanosis; Ostium secundum atrial septal defect; Pulmonary hypertension.

Publication types

  • Case Reports

MeSH terms

  • Animals
  • Dogs / abnormalities*
  • Echocardiography, Doppler / veterinary
  • Heart Septal Defects, Atrial / diagnostic imaging
  • Heart Septal Defects, Atrial / veterinary
  • Lung / blood supply
  • Lung / diagnostic imaging
  • Male
  • Pulmonary Veins / abnormalities*
  • Radiography, Thoracic / veterinary
  • Tomography, X-Ray Computed / veterinary