Half of the deaths from heart disease are linked to smoking. It reduces the blood flow to the heart and nicotine and carbon monoxide damage the linings of the coronary arteries. Lung damage from smoking can result in less oxygen in the blood and so the heart has to work harder.
It is difficult to stop smoking so think positively and use support groups. You will feel healthier, have a better sense of smell and taste and you will save money too. You will have a reduced risk of heart disease.