Cardiac Tumor Stenting

Central venous obstruction can have profound systemic effects. Interventional radiology techniques have been used to palliate both malignant and non-malignant causes of vascular obstruction for both intrinsic and extrinsic lesions. The author has been presented with a number of dramatic cases of venous obstruction in dogs due to naturally occurring large cardiac masses not amenable to traditional veterinary therapies. To the author’s knowledge, placement of transatrial stents or pulmonary artery stents for long-term decompression of cardiac tumor venous obstruction has not been previously reported. Transatrial stents may be a safer alternative to stent free ends within the atrium or the stent migrating into the ventricle.

Three dogs recently reported in abstract form presented with large, non-resectable cardiac masses obstructing venous return to the right atrium. Venous return to the heart was severely obstructed leading to congestion with subsequent ascites (2) or head swelling and pleural effusion (1). Due to the extensive nature of the disease, an interventional palliative approach was pursued. Transatrial self-expanding metallic nitinol stents were placed from the CdVC to the CrVC in order to restore venous return to the heart via blood flow through the stent interstices. One example of cranial vena cava and one example of caudal vena cava obstruction are presented below for demonstration purposes.

Caudal vena cava obstruction: A 9 year-old male castrated Petite Bassett Griffon Vendene (PBGV) dog was evaluated for a 3 week history of progressive abdominal distension and lethargy. On physical examination a palpable abdominal fluid wave was present as well as a grade 2-3/6 heart murmur and generalized muscle wasting. Subsequent medical work-up confirmed the presence of ascites (modified transudate), an anterior mediastinal mass, and a large vascular mass filling the right atrium, involving the atrial septum, and extending into the left atrium. There was no jugular vein distension. The dog was diagnosed with a cardiac tumor resulting in subsequent inferior vena cava obstruction and subsequent Budd-Chiari-like syndrome [...]