Interventional Radiology Management of Vascular Obstruction

Transatrial stenting for long-term management of cardiac tumor obstruction of the right atrium in 3 dogs

Background

Venous obstruction in dogs caused by large intracardiac masses can result in severe morbidity with few safe treatments.

Hypothesis/Objectives

Retrospective study to report results after transatrial stent placement in dogs with naturally occurring cardiac masses causing venous obstruction.

Animals

Three client‐owned dogs diagnosed with large cardiac masses.

Methods

Retrospective study of patients that received transatrial stents extending from the caudal vena cava, across the right atrium, and into the cranial vena cava (CrVC). Procedures, complications, and outcomes were recorded based upon medical records, referring veterinarians, and client communications.

Results

Two dogs had similar clinical signs suggestive of congestive hepatopathy including marked ascites and lethargy. One dog had clinical signs of CrVC syndrome including head and neck swelling with pitting edema and pleural effusion. After stent placement, venous pressure gradients were decreased and repeat angiography confirmed that vascular patency was reestablished. Resolution of clinical signs was marked in all 3 dogs with only mild complications including tachyarrhythmias and hypertension in 1 dog during the perioperative period. Two dogs that required additional transatrial stent placement for reobstruction 6 and 14 months later improved after the second stent implantation. Survival times poststenting for the dogs were 3, 21, and 37 months, with cause of death related to the cardiac tumor in all dogs.

Conclusions and Clinical Importance

Endovascular transatrial stenting may provide a long‐term palliative treatment option for dogs with clinical signs attributable to tumor‐induced venous obstruction when more traditional treatments are declined or not indicated.

Outcome and treatments of dogs with aortic thrombosis: 100 cases (1997-2014)

Background

Aortic thrombosis (ATh) is an uncommon condition in dogs, with limited understanding of risks factors, outcomes, and treatments.

Objectives/Hypothesis

To describe potential risk factors, outcome, and treatments in dogs with ATh.

Animals

Client‐owned dogs with a diagnosis of ATh based on ultrasonographic or gross necropsy examination.

Method

Multicentric retrospective study from 2 academic institutions.

Results

One hundred dogs were identified. Anti‐thrombin diagnosis, 35/100 dogs were nonambulatory. The dogs were classified as acute (n = 27), chronic (n = 72), or unknown (n = 1). Fifty‐four dogs had at least one comorbidity thought to predispose to ATh, and 23 others had multiple comorbidities. The remaining 23 dogs with no obvious comorbidities were classified as cryptogenic. Concurrent illnesses potentially related to the development of ATh included protein‐losing nephropathy (PLN) (n = 32), neoplasia (n = 22), exogenous corticosteroid administration (n = 16), endocrine disease (n = 13), and infection (n = 9). Dogs with PLN had lower antithrombin activity than those without PLN (64% and 82%, respectively) (P = .04). Sixty‐five dogs were hospitalized with 41 subsequently discharged. Sixteen were treated as outpatient and 19 euthanized at admission. In‐hospital treatments varied, but included thrombolytics (n = 12), alone or in combination with thrombectomy (n = 9). Fifty‐seven dogs survived to discharge. Sixteen were alive at 180 days. Using regression analysis, ambulation status at the time of presentation was significantly correlated with survival‐to‐discharge (P < .001).

Conclusions/Clinical Importance

Dogs with ATh have a poor prognosis, with nonambulatory dogs at the time of presentation having worse outcome. Although the presence of comorbid conditions associated with hypercoagulability is common, an underlying cause for ATh was not always identified.

Surgical embolectomy in a cat with cardiogenic aortic thromboembolism

A seven-year-old, spayed female, domestic longhair cat was referred for management of a sudden aortic thromboembolism (ATE). Echocardiography showed hypertrophic cardiomyopathy with severe left atrial enlargement. Ultrasonography of the abdominal aorta confirmed a large thrombus at the level of the aortic trifurcation, involving both iliac arteries. Considering the recent onset and bilateral involvement of the iliac arteries, the cat underwent emergent surgical embolectomy (SE) of the aortoiliac embolus. A standard caudal celiotomy was performed and the abdominal aorta was identified. Vessel loops with tourniquets were placed around the abdominal aorta proximal to the thrombus and on both iliac arteries distal to the thrombus. A full-thickness incision was made in the ventral surface of the aorta. The aortic thromboembolus was removed. The trifurcation was subsequently flushed with sterile saline. The SE resulted in a good outcome, with both clinical and ultrasound signs of complete reperfusion of the rear limbs within a few hours. Long-term treatment included antiplatelet drugs, furosemide and benazepril. Eighteen months after surgery, the cat was free of clinical signs, without recurrence of ATE or congestive heart failure. Based on the present case, SE could be considered as a feasible alternative to traditional conservative treatment in cats with a very recent onset of bilateral ATE.