The summer season is in full swing. What risks for the heart are hidden by high temperatures and what rules must be followed in order to protect ourselves from cardiovascular complications - these questions are answered by the cardiologist at "Alexandrovska" University Hospital, Dr. Pavel Nikolov.
Dr. Nikolov, does heat affect heart activity and how?
- The human body is designed in such a way that it can tolerate large variations in the temperature of the environment, while a small increase in body temperature (for example by 3 degrees) can have serious consequences and damage. We have two main defense mechanisms that are activated in hot weather - increased blood flow in the skin and sweating. They, in turn, are directly dependent on the cardiovascular system.
As a compensatory reaction, the pumping function of the heart increases, the heart rate increases. For this reason, patients with cardiovascular insufficiency also have a harder time tolerating the heat.
Often, however, in warm weather, even in he althy people, the pulse accelerates. Should this concern us?
- Accelerated heart rate at elevated temperature outside is a physiological defense mechanism and is not worrisome as long as it is within certain limits. Normally, the heart rate varies between 60 and 80 beats per minute, and in certain groups of people it can drop to 45-50 beats/minute (for example, athletes) or rise to 90-95 beats/minute, without requiring appropriate treatment.
Maximum heart rate during exercise is calculated according to the following formula: 220 - the age, i.e. for a 50-year-old person, physical activities in which the heart rate exceeds 170 beats/minute are not recommended.
Tachycardia is an increase in the heart rate over 100 beats/minute, and when it is documented, it is appropriate to carry out the appropriate tests to determine the cause. The most common symptoms are palpitations, sweating, "heart skipping", and there are also tachycardias, in which there is an immediate danger to life with loss of consciousness due to ineffective contractions of the heart.
What measures should we take to get our heart back into a normal rhythm?
- In a certain group of tachycardias, especially in supraventricular tachycardias, vagus techniques can be tried, such as light and brief squeezing and massaging of the carotid arteries, taking in air and straining the abdominal wall with a stuffy nose. These methods can help, but only if it is the type of rhythm-conduction disorders described above.
There are quite a number of drugs that affect the heart rhythm, and they are divided into two large groups - those that maintain the normal (sinus) rhythm and those that slow the heart rate, regardless of whether the rhythm is physiological or pathological. These medicines can only be taken with a doctor's prescription.
It is widely believed that a heart rate below normal is the lesser evil. Is it really so?
- There are people who live for many years with a heart rate below normal without having any complaints, either because of individual peculiarities in the rhythm-conducting system or because of long-term practice of aerobic sports such as swimming, running, etc. I wouldn't say that having pathological bradycardia (slow heart rate) is better than having a higher than normal heart rate. However, treatment methods differ.
Which people are most vulnerable in the heat? What rules should they follow to protect themselves from cardiovascular complications?
- The most vulnerable in the heat are children, pregnant women and the elderly with accompanying cardiovascular diseases. The recommendations are to avoid particularly hot hours (between 11 a.m. and 5 p.m.), to take a sufficient amount of fluids, and it is advisable to avoid the intake of coffee and carbonated drinks due to their pronounced diuretic effect (increases urine output). During the hot summer days, it is good to be appropriately dressed in light, loose clothes made of natural materials.
What is a reasonable amount of water to drink, including by people with high blood pressure?
- Fluid intake should be tailored to the individual's age, sex, diet, physical activity, external temperature and humidity, as well as the presence of accompanying diseases. For children up to 10 kg, a daily intake of at least 100 ml of water per kg of body weight is accepted. For adults between 30 and 50 ml/kg of body weight, this formula does not apply to people with kidney and/or heart failure taking medications that stimulate diuresis.
For them, the liquid intake is reduced and tailored to the individual condition and needs. Accordingly, with heavy physical activity, fluid needs increase.
Many people seek relief from the heat in cold beer. Does it help to tolerate them more easily?
- Beer is a nice way to cool off in the summer heat. A good source of minerals and B vitamins, my advice is to look to other main sources for the relevant vitamins. Consumption should be in moderation. The heart "loves" water in its pure form.