Smoking and heart

Smoking is one of the strongest risk factors for heart diseases. It contributes to the development and increase in severity of the heart diseases. Both active smokers and passive smokers (those who do not smoke but indirectly smoke by inhaling the cigarette smoke of smokers) are affected by smoking. It is proved that the number of cigarettes smoked is directly proportional to the possibility of acquiring a heart disease and cessation of smoking decreases the risk of heart disease by 50%. Smoking affects the heart, lungs, kidneys and all the blood vessels of our body. In this article, we will see how smoking affects the heart in particular.

There are three main ways of how smoking affects the heart. First, the inhalation of smoke increases the blood carbon monoxide (CO) level. The oxygen carrying component of blood called hemoglobin readily combines with carbon monoxide more than it does with oxygen. So the oxygen carrying capacity of blood drops very low. Thus, the oxygen that has to be supplied to the heart is severely impacted, which makes the heart to work much harder to produce the same amount of energy. This causes a lot of strain to the heart to pump a lot of blood.

Secondly, cigarettes (tobacco product) contain a chemical substance called nicotine (or nicotinic acid) which stimulates the sympathetic nervous system to release catecholamine which constricts the blood vessels and causes an increase in the heart rate and blood pressure. Hence the blood flow and subsequent oxygenation are compromised. Since the blood vessels constrict, heart has to pump harder to keep the blood flowing through these constricted veins thereby increasing the workload of the heart.

Also smoking increases the chance of the blood to clot by increasing the aggregation of platelets. So clots can easily form in blood vessels and can block blood flow to vital organs including heart, causing irreparable damages to heart and other important organs.

Smoking causes buildup of fatty substances in the arteries thereby narrowing the arteries which supply blood to the heart and so the heart is starved of oxygen. This narrowing of arteries causes chest pain as heart has to put on extra effort to pump blood through these narrow arteries. The problem is magnified especially during increased physical activity. When one or more arteries supplying blood to the heart get blocked completely, heart attack occurs. Smoking also decreases high density lipids which is good for the body. Cigarette smoke also can lead to a stroke.

Thus smoking can cause severe damage to heart in multiple ways.