Smoking: The Damage to Heart and Arteries
Quitting smoking is a key step in preserving the health of the heart and arteries and in reducing the likelihood of severe cardiovascular events.
Interview with Dr. Marco Stefano Nazzaro, cardiologist at UPMC Salvator Mundi International Hospital.
May 31st is “World No Tobacco Day”, a campaign created by the World Health Organization (WHO) to raise awareness and educate about the harm caused by cigarette smoking, one of the leading causes of death in the world. According to the WHO, tobacco smoking is responsible for more than 8 million deaths each year, of which, about 7 million are caused by cardiovascular diseases directly related to tobacco consumption. We asked Dr. Marco Stefano Nazzaro, a cardiologist specialized in myocardial infarction, to identify the main damage caused by smoking.
What is the main damage that smoking can cause to the heart and arteries?
Cigarette smoking significantly increases cardiovascular risk and contributes to the development of cardiovascular diseases through several harmful mechanisms. Notably, smoke damage is cumulative over time. The more and the longer a person smokes, the greater the risk of cardiovascular damage.
Significantly, smokers are up to four times more likely to develop cardiovascular diseases than non-smokers. In addition, smoking can significantly reduce the life expectancy of smokers, on average, by 8 years.
The adverse effects of smoking on the cardiovascular system can be direct, for example those that damage arterial walls that become less elastic, and indirect, i.e., they lead to an increase in bad cholesterol (LDL) and a decrease in good cholesterol (HDL), damaging the internal wall of blood vessels. The bad cholesterol accumulating in the arteries can form plaques and accelerate a process called atherosclerosis, which can hinder blood flow and reduce blood supply to the heart. Plaques can grow over time, thus restricting blood vessels and hindering blood flow to the heart. When a plaque breaks open, it causes a blood clot that can completely obstruct an artery, causing a myocardial infarction, which is often fatal.
The combination of these harmful effects increases the likelihood of developing obstructive plaques and the formation of blood clots, known as thrombi, in the blood vessels. This can lead to serious cardiovascular events, such as a stroke or a heart attack.
What are the harmful substances in tobacco that can worsen the progression of cardiovascular diseases?
Increased heart rate, more intense contraction of heart cells, increased blood pressure, and reduced oxygen supply to tissues are among the main effects of nicotine and carbon monoxide in tobacco. These effects are most evident in people with pre-existing cardiovascular diseases, but they can contribute to the onset and progression of cardiovascular diseases in the long term also in apparently healthy people.
Nicotine, a drug contained in tobacco leaves, is addictive and has an immediate impact on the central nervous system and on the cardiovascular system. Nicotine acts as a powerful stimulant, boosting heart rate and causing heart cells to contract more rapidly with each beat. This can put stress on the cardiovascular system and increase blood pressure. Increased heart rate and blood pressure can damage the arteries and encourage the development of atherosclerotic plaques, which can hinder blood flow and increase the risk of cardiac events such as a heart attack.
By binding to the hemoglobin in the blood, carbon monoxide reduces its ability to carry oxygen to various organs and tissues in the body. This generates a decreased oxygenation of tissues, including those of the heart. Insufficient oxygen supply can damage heart cells and worsen the condition of people with pre-existing heart diseases.
What alarm bells should a smoker monitor to identify possible heart problems?
The signs of heart disorders or diseases may vary from person to person, but there are some common symptoms to look out for. One of the most common is chest pain. If a smoker experiences chest pain or tightness at the base of the neck, or even heartburn, it could be a sign of angina, a heart problem related to an insufficient blood supply to the heart, which we have already discussed. This pain can occur during physical activity or stressful situations and can be relieved with specific medications.
Another alarm bell is the difficulty breathing, i.e., dyspnea, which may be a sign of heart failure, when the heart cannot pump enough blood to meet the body requirements. Palpitations are another signal to monitor: an irregular or accelerated heartbeat could be a sign of cardiac arrhythmias. Persistent fatigue and weakness may indicate poor blood circulation to the heart and the rest of the body. Finally, swelling of the legs and ankles: if a smoker notices an accumulation of fluids in the legs and ankles, a cardiologist should immediately be consulted for an accurate assessment of cardiac health.
So: pain, dyspnea, weakness, and swelling of the legs are four alarm bells that need immediate attention.
Does the risk exist also for those who do not smoke, but live with a smoker?
Yes: passive smoking, or the inhalation of smoking by non-smokers, can increase the risk of developing cardiovascular diseases. Out of the 8 million deaths per year from smoking in the United States, nearly 1 million are caused by passive smoking.
If we quit smoking, what benefits can we observe?
Quitting smoking is the most important step a smoker can take to improve the health of the heart and arteries. The positive effects are already evident after a short period of time. Just 20 minutes after the last cigarette, blood pressure and heart rate begin to drop. Over the course of a few years of smoking abstinence, the risk of cardiovascular diseases decreases considerably.
For those with a heart disease or who underwent heart surgery, quitting smoking is the most effective way to reduce the likelihood of experiencing a worsening of the disease. A review of 20 studies conducted in different countries in patients with ischemic heart disease or undergoing coronary surgery showed a 36% decrease in mortality and a 32% reduction in heart attacks for those who quit smoking compared to those who continued smoking. These benefits are already evident two years after quitting.
In conclusion, if you quit smoking, the risk of cardiovascular diseases reduces considerably approximately after one year and, after 20 years, it is again comparable to that of a person who has never smoked.