Cranial Vena Cava SyndromeIsn’t that the thing with heartworm disease???

Trisha Oura, DVMMarch 1, 2010

Acc # 125214 (Motown)- 10 yo FS GSD- 3 week history of submandibular swelling now cervical and forelimb- Coughing (especially at night), decreased appetite- Thoracic radiographs: pulmonary nodules- Abdominal ultrasound: cavitated splenic mass- CT:

-Bilobed, partially mineralized thyroid mass with esophageal compression- Vascular filling defects

- left external jugular v, cranial vena cava

- Pulmonary nodules- Cervical, thoracic lymphomegaly- Marked subcutaneous edemaCRANIAL VENA CAVA

SYNDROME

Cranial Vena Cava Syndrome

Uncommonly reported in veterinary literatureBronchogenic carcinoma, LSA = 95% human

casesPathophysiology:

Compression, invasion, intraluminal obstruction

Elevated hydrostatic pressureInterstitial fluid leakage, overwhelms

lymphatics

CrVCS

Clinical signs:Subcutaneous, pitting edema (head, neck,

forelimbs), jugular/scleral/conjunctival venous distension** usually symmetrical **

Pleural effusion (chylous), rarely pericardial

Gradual or acute onsetCollateral circulation within 1 week

CrVCS

Reported causes: Thymoma (canine)Mediastinal lymphomaFungal (blastomycosis)CarcinomaAortic body tumorsPacemaker and IV catheter associated thrombi

CrVCS

Ddx: Angioedema Snake bite Trauma Salivary mucocele Abscess/cellulitis Hypoalbuminemia/vasculitis (usually

generalized)Diagnostics: Image! Image! Image! and aspirate…

CrVCSTreatment

Remove the underlying cause if possible Surgery/chemotherapy/radiation for neoplasia Remove catheters/lead wires

Thrombolytics Interventional

Balloon/Stent

Prognosis:Guarded to poor

Collateral circulation Invasive tumors not amenable to therapy

Pacemaker induced caval thrombus and stricture formationCunningham SM, et al. JAVMA 2009;235:1467-1473.

2 cases with pacemakers placed years ago1 = acute clinical signs (dyspnea, swelling)

Large volume recurrent PFCrVC thrombus/stricture on CTThrombolytics, anticoagulants, balloon venoplasty

1 = chronic, ‘incidental’Found at pacemaker replacement

Collateral vessels seen on angiographyBalloon venoplasty

Pacemaker induced caval thrombus and stricture

formation

Case 1: acute onset clinical signsCase 2: asymptomatic, incidental

Good outcome > 6 months!

Not to be confused with….Heartworm Caval Syndrome

Life-threateningThought to occur with large numbers of worms

maturing in short timeSevere pulmonary hypertension, CO Adults migrate from MPA to RA, RV +/- vena

cavaMechanical disruption of TV, physical

obstructionTrauma to RBC, hemolysis, anemia, icterusExperimentally = as low as 12 worms (mean

= 40)

References

Bove CM, et al. Outcome of minimally invasive surgical treatment of heartworm caval syndrome in dogs: 42 cases (1999-2007). J Am Vet Med Assoc 2010;236:187-192.

Cunningham SM, MK Ames, JE Rush, EA Rozanski. Successful treatment of pacemaker-induced stricture and thrombosis of the cranial vena cava in two dogs by use of anticoagulants and balloon venoplasty. J Am Vet Med Assoc 2009;235:1467-1473.

Ncastro A, E Cote. Cranial vena cava syndrome. Compend Contin Educ Pract Vet 2002;24:701-710.