As few as 2 adult heartworms can cause cardiac enlargement and severe respiratory compromise in cats. Use of echocardiography to view heartworms may indicate whether surgical removal is possible. Aided by fluoroscopy, manual insertion of a catheter that contains basket-type retrieval forceps into the right atrium, via jugular venotomy, may permit removal of adult heartworms from cats. Surgical removal of heartworms and supportive treatment with heparin, prednisone, and antibiotics may result in complete recovery from heartworm infection in cats.