By Dr. Brian McDonough, Medical Editor

PHILADELPHIA (CBS) – What do you think cardiologists think is the greatest risk for heart disease? It’s quite simple. Cigarette smoking can help lead to clogged blood vessels. And, as we know, when the blood vessels that supply the heart become clogged it can lead to a heart attack.

There are other risk factors like high cholesterol, lack of exercise and family history but cigarette smoking is the major lifestyle intervention that can damage the heart. Even if you exercise regularly you cannot make up for the damage.

In addition, most people don’t smoke cigarettes and run out and exercise, but if you ever tried it you would realize how it limits the amount you can exercise. The combination of lack of exercise and smoking cigarettes could be like playing Russian roulette. It’s all a matter of timing.

If you’ve been a smoker for years and want to start an exercise program, you can do it, but understand that you need a careful workup with an EKG and a stress test. But if you want to make a major stride in helping your heart – stop smoking.

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