COMPARISON OF LABORATORY TEST-RESULTS BEFORE AND AFTER SURGICAL REMOVAL OF HEARTWORMS IN DOGS WITH VENA-CAVAL SYNDROME

Objective-To compare results of laboratory tests in dogs with vena cav al syndrome before and after surgical removal of heartworms. Design-Lo ngitudinal uncontrolled clinical trial. Animals-51 dogs with vena cava l syndrome. Procedure-Heartworms were removed from the area of the tri cuspid valve and pulmonary arteries via venotomy and by use of flexibl e alligator forceps. Blood samples were obtained before and 10 days af ter removal of heartworms. Red and white blood cell counts were determ ined, using an automated cell counter. Biochemical tests were performe d, using a dry chemical method. Results-45 dogs survived the procedure , and 6 died or were euthanatized after surgical treatment. After surg ery, RBC count and total protein, albumin, calcium, and sodium concent rations increased, and total bilirubin, ammonia, BUN, creatinine, uric acid, and potassium concentrations decreased in dogs that survived. C reatine kinase. L-lactate dehydrogenase, and amylase activities decrea sed, whereas alkaline phosphatase and gamma-glutamyltransferase activi ties and total cholesterol concentration increased. Alanine transamina se activity decreased in 27 dogs but increased in 3 dogs. Changes in t est: results in dogs that did not survive were similar to those in dog s that did survive. Significant differences were found in RBC count, g amma-glutamyltransferase activity, and total protein, total cholestero l, BUN, and total bilirubin concentrations before and after removal of heartworms. Clinical Implications-Hepatic and renal functions improve rapidly after surgical removal of heartworms, presumably because gene ral and pulmonary circulation is normalized. However, cholestasis may develop, and dogs that survive may need additional treatment to preser ve hepatic function.