Walk into the office of cardiologist Stephen Sinatra, and you'll be greeted not just by his friendly staff, but also a few gregarious four-legged receptionists.

Chewy and Kuma, both chows, and Charlie, a Norwegian elkhound, are happy to cheer you up, sit by your side and welcome a scratch behind the ears.

While these three pooches make most of Sinatra's patients smile and feel good, they're not there for the patients' benefit alone. Sinatra brings in his furry family members as a way to keep him energized and calm, so he's at his best while treating patients all day.

"It's not their fault, but some patients can be cruel at times. A lot of them are suffering and it's definitely understandable, but it can drain you as a physician," he says. "And you don't want to bring toxic energy from one patient to another."

Between patients, his dog Chewy, the oldest chow, will often follow him into his office. "I'll sit and pet my dog. Make loving contact with her eyes, and I'll be renewed to go to the next patient," remarks Sinatra.

In other words, these healing dogs are his on-site therapists. "I practice much better medicine when the dogs are in the office," says Sinatra, who runs the Heart and Longevity Center in Manchester, Conn.

Science Behind Why We Love Pets
And he preaches what he practices. In his book Heart Sense for Women, Sinatra mentions the various benefits pets can have on our health. One of the most important is alleviating loneliness.

In fact, loneliness is one of the most damaging risk factors in people recovering from heart disease. Studies have shown that patients who suffer heart attacks but own pets are likely to have five times the survival rate of patients who are not pet owners, according to Sinatra.

Another big benefit of being in the presence of a pet is that it can induce relaxation. The simple act of petting an animal is known to cause a person's blood pressure to drop, says Alan Beck, ScD, director of the Center for the Human-Animal Bond at Purdue University.

The relaxation doesn't just affect people, it affects the animal, too. "We've shown that when you pet a dog, not just your heart rate slows down and blood pressure drops, but so does the animal's," Beck says. This indicates a true, mutual human-animal bond.