Wichita ? Two 10-year-old gorillas at the Sedgwick County Zoo passed their heart exams with flying colors over the weekend.

That was the good news after Jabir and Samson underwent an elaborate medical screening performed by physician Ravi Bajaj of Heartland Cardiology and several other medical professionals.

Sedgwick County asked Bajaj to perform the heart exam as part of a national effort to determine why gorillas in captivity are dying of heart disease and other complications.

Bajaj said it’s unclear why captive gorillas have a high instance of heart failure. Males in their 20s and 30s have been particularly susceptible to heart-related illnesses, staff members said.

Several zoos in the country are scheduling their gorillas for an electrocardiogram, or EKG, to detect the heart’s rhythm and weaknesses in different parts of its muscles.

“We hope to find out what’s causing the heart muscle weaknesses and how to treat it,” Bajaj said.

During the exams Saturday, a team of medical professionals, zookeepers and Douglas Winter of the Veterinary Emergency and Specialty Hospital of Wichita surrounded the operating table. They examined a sedated Jabir first, listening to his heart with a stethoscope. An ultrasound captured on a television mounted above Jabir’s head showed his heart pumping. Then it was Samson’s turn.

“They both have healthy hearts. That’s what our hopes were,” Bajaj said.

The zoo plans to examine all eight of its gorillas.