Abstract
Canine filariasis is a common disease among adult dogs in Japan. Usually the sick dogs die of the impairment of blood circulation caused by a large number of adult heartworms (Dirofilaria immitis) harbored in the right ventricle of the heart or the pulmonary arteries. As a rule, this disease is treated with pharmaceuticals, such as antimonial and piperazine compounds (microfilaricides) and arsenical preparations (adulticides)2, 9∼11, 27, 28)<. However, when an infected dog has been suffering from some ailment of the liver or harboring an extremely large number of heartworms, little effect or even danger is expected from the treatment with such drugs. In such case only symptomatic treatment may be applicable and prognosis is not good. Hazard has been recognized in various surgical methods for the removal of adult heartworms<3, 13∼21, 29). It does not seem feasible to employ these surgical methods in veterinary practice, beouse accurate laboratory diagnosis is necessary to find the habitat of heartworms before they are carried out and prudent care should be taken after operation. Since 1950 I have been conducting studies on the surgical treatment of canine filariasis, using 235 dogs in total, to cure the impairment of blood circulation caused by the embolus of heartworms harbored in the right ventricle of the heart and the pulmonary arteries. From these studies5, 12∼24), I devised an angiocardiographic method to locate the habitat of heartworms and a new technique of cardiac surgery, which I called the K technique, for the removal of heartworms. This paper deals with the pre-operative angiocardiographic diagnosis and the operative method, or the K technique, for the removal of heartworms, describing the most typical of 159 cases that I have treated.
