Mokolo, 20, and Bebac, 23, were examined and diagnosed earlier this month at the Cleveland Metroparks Zoo as part of a national study of gorilla health.
Veterinarian Albert Lewandowski said Monday that Bebac has advanced heart disease. Mokolo shows signs of early heart disease.
The gorillas will be treated with beta blockers or ACE inhibitors, which treat high blood pressure and heart disease in people. The medication should help stem the progression of the disease and hopefully improve the gorillas' long-term survival.
The animals came to the Zoo in 1994 from Lincoln Park Zoo in Chicago. Gorillas at zoos around the country have received similar treatment.
