Human pulmonary dirofilariasis (HPD) is an uncommon disease in the United States. Dirofilaria is commonly known as "heartworm" based on the false belief that the worm resides in the heart which was based on findings from early necropsy reports. The first case was reported as an incidental autopsy finding in 1941. Since then only 87 more cases have been reported so far. We present an interesting case of this rare zoonotic disease affecting an elderly gentleman who presented with a rapidly growing lung nodule. We present a brief review of literature concerning the diagnosis and management of this disease.