Smoking damages your heart and your blood circulation, increasing the risk of conditions such as coronary heart disease, heart attack, stroke, peripheral vascular disease (damaged blood vessels) and cerebrovascular disease (damaged arteries that supply blood to your brain).
Carbon monoxide from the smoke and nicotine both put a strain on the heart by making it work faster. They also increase your risk of blood clots. Other chemicals in cigarette smoke damage the lining of your coronary arteries, leading to furring of the arteries.
In fact, smoking doubles your risk of having a heart attack, and if you smoke you have twice the risk of dying from coronary heart disease than lifetime non-smokers.
The good news is that after only one year of not smoking, your risk is reduced by half. After stopping for 15 years, your risk is similar to that of someone who has never smoked.
Read more at https://www.nhs.uk/smokefree/why-quit/smoking-health-problems#0qg16IlfP13mFFLC.99