It's a slow-moving disease that sometimes starts developing as early as childhood.
Atherosclerosis is when plaque builds up in the arteries, blocking blood flow to the heart.
Doctors perform more than one million angioplasties in the US every year to unclog the problem.
What was once a complicated procedure, is now much simpler, as doctors reach the heart through the wrist.
Robert Santopietro looks and feels like a healthy 46-year-old.
He said, "I started working out, getting back into shape, New Year's resolution."
So when he ran out of breath and felt chest pains during workouts, he brushed it off.
Santopietro said, "I just put it off to Iate before I went to go work out."
The pain persisted. Robert had atherosclerosis. Plaque was building up in his arteries.
Interventional Cardiologist Dr. Michael Azrin said, "That plaque may become restrictive enough that there's inadequate flow, or more emergently, some degree of clot may form."
Robert needed an angioplasty to unclog his arteries. Instead of traditional technique, where doctors reach the heart by inserting a catheter through the femoral artery in the leg, Robert had a wrist angioplasty. Doctors thread a tiny balloon through the catheter and guide it into the blockage.
In a leg angioplasty there's an up to 10-percent risk of heavy bleeding. One study shows the wrist procedure cuts that risk by 60 percent.
Dr. Michael Azrin said, "When you're done, you pull the tube out and put a bandage on the wrist, and the patients can sit up. They can walk around. They can return to normal function very quickly."
Robert's stepfather, Dan, had the procedure done less than a week ago.
He said, "Before, I'd get halfway up the stairs and have to stop, and now, I can go all the way."
Robert is also noticing a difference, "I feel 100 percent better. Knowing what could have happened and didn't happen is just amazing."