An arterial condition that affects about one million Canadians often goes undetected, leaving its victims at risk of heart attacks, strokes, gangrene and amputations.

Peripheral arterial disease, or PAD for short, is a form of cardiovascular disease that affects the legs.

Specialists are urging doctors to test for the condition as a simple way of preventing what could be dire consequences.

"It's been under-diagnosed," said Dr. Andre Roussin of the University of Montreal Medical Centre.

PAD occurs when the arteries that supply blood to the legs, arms or neck become narrow and blocked. Blood flow to the legs is weakened, sometimes leading to gangrene to the lower limbs. It is most common in those over 50 who smoke, have diabetes, hypertension, or high cholesterol.

"PAD is a silent killer because it is an advanced form of atherosclerosis or hardening of the arteries," said Dr. Thomas Lindsay, a vascular surgeon at the Toronto General Hospital.

People in their 40s and older are most at risk.

Frank Tassone, 48, lost one leg to diabetes. He may lose his other, in part, to PAD -- a disease he initially ignored despite pain in his legs and a toe that was turning black.

"I knew it was getting worse, I just didn't want to deal with it," he said.

"I would have to use a cane, the pain in the groin was so much. It was like it was put in a vice. Then the pain went to my knee. Then my knee started to swell up."

Untreated, PAD can lead to heart attacks, strokes and early death.

"Peripheral arterial disease is really quite dangerous. It's a bit like an iceberg," said Roussin. "Some people will present with leg pain but most patients are not symptomatic but have the disease."

Symptoms

Those who do have symptoms often have skin wounds or ulcers on feet and toes, or severe pain, fatigue or cramping in their legs that limits their ability to walk but stops when they stop walking.

"PAD is literally pain or a toughening of the calf when someone is walking," said Roussin. "So it's leg pain, sometimes as a cramp, and it appears after a block or two or walking."

Jacques Grimard, who has also been diagnosed with PAD, says he couldn't walk more than 10 minutes. "It's so painful, you won't believe it," he said.

Other symptoms include lack of toenail growth, cold feet and withered calf muscles.

Even among those who show no symptoms, there's still plaque building in their leg arteries and probably throughout their bodies, and they have up to six times the risk of having a heart attack or stroke compared to a person with good circulation in peripheral arteries.

"PAD puts someone at risk of heart attacks or stroke. Because if you have the disease in your legs, you most certainly have it in your heart and carotids," said Roussin. "So it is a marker for more generalized vascular disease which can lead to heart attack or stroke, which is why it's so important to find it."

Both Roussin and Lindsay believe that PAD goes under-diagnosed because not enough doctors are looking for it.

"PAD doesn't have the same sort of awareness as do heart attacks or stroke, but it is an important form of atherosclerosis or hardening of the arteries," Lindsay said.

There are tests, such as Doppler ultrasounds, to measure blood flow to the legs. Other doctors can feel for the strength of the pulse through the arteries in a patient's legs.

And another simple test involves doctors measuring blood pressure in the legs. If it's lower than the blood pressure in their arms, it indicates diminished blood flow to the legs -- a sign of PAD.

Treatment can include diet and exercise changes, quitting smoking, drugs to lower cholesterol or blood pressure, and anticoagulants, like Aspirin, to prevent blood clots.

Others like Tassone will need angioplasty to quickly open blocked arteries in their legs. When doctors performed the procedure on Frank, they found he had only one healthy artery among the three main arteries in his legs.

The angioplasty saved Tassone's leg. But doctors were unable to open arteries to his foot. So he had all his toes amputated.

Tassone said he wants others to hear his story so that they can learn more about PAD. "Believe me, you don't want to end up the way I have," he said.

Specialists in the field of PAD want family doctors to start testing more patients for PAD and for patients to ask for the tests.

"It's important family physicians realize PAD is as important as cardiovascular disease," said Roussin. "Check in all patients over 50."

With a report from CTV's Avis Favaro and medical producer Elizabeth St. Philip