They are fairly large worms that can grow up to 14 inches long and can live there for up to 5 - 7 years. (dallasmetropaws.com)
It is caused by large worms (1 foot in length) that live inside the heart and lungs of affected animals which causes severe lung and heart disease. (rocketcitymobilevet.com)
Several large worms can be found on the feces of cats, although few actually cause diarrhea. (napahumane.org)