This is an updated version of a column that was first published in February 2019.
Have you ever noticed that when organizations are trying to raise awareness about something, try to tie it to an event or celebration that relates? February is all about Valentines and Love, so of course, if you want to raise awareness about the heart’s issues, what better time of year! So, you are likely to have seen and heard public service announcements about heart health, exercise, and CPR (cardiopulmonary resuscitation) throughout the month. But, let’s do a little more in-depth investigation.
First, the heart is a muscle and acts like a pump. It is about the size of your fist and is located just behind and slightly to the left of the breastbone, which is why when doing CPR, you do the chest compressions one hand on top of the other centered in the middle of the chest on the breastbone. The heart is a four-chambered pump consisting of two atriums, chambers that receive blood from outside the heart, and two ventricles that pump the blood outside of the heart. The atrium chambers are located at the top, and the ventricles are located at the bottom. The blood enters the heart from the veins at the right atrium. The blood is then pushed or pumped through a valve to the right ventricle, which then pumps the blood to the lungs, where it is oxygenated. The oxygenated blood returns to the hearth through the left atrium and is then pumped to the left ventricle. The left ventricle is the strongest chamber and is responsible for pushing the oxygenated blood out to the rest of the body. The actions of the left ventricle resulting in our blood pressure.
The heart contains two types of cells that use electricity to produce the heart “beat” or pumping action. One type conducts the electricity to carry the signals, much like a wire carries the current to a light bulb. These are the myocardial conducting cells. The other type causes the muscles to contract. These are the myocardial contractile cells and constitute the bulk of the cells in the atria (more than one atrium) and ventricles. The timing of the contractions in the different areas of the muscle is what produces the pumping action. Each beat of the heart is triggered by an electrical impulse generated by the SA node, the heart’s natural pacemaker, near the right atrium. And, if things are working properly, causes the atria to contract, which then triggers a signal in the AV node, which sends an impulse to the ventricles, which contract, and then the cycle is repeated. These electric signals are what are being monitored when a person has an electrocardiogram. A problem with the heart’s electrical signal may show up as an arrhythmia or an irregular heartbeat.
For the heart to function, the heart must be properly supplied with oxygen, and the electrical system must work, as well as having all the valves function as designed. A heart attack occurs when the blood flow is blocked, preventing the heart from receiving the oxygen needed. The blockage can be a clot or due to plagues which are build-up of fat, cholesterol, and other substances that causes the coronary arteries to harden and reduce the flow of blood. Without oxygen, the cells die, which means they can produce the pumping action needed to supply blood to the rest of the body. Symptoms of a heart attack can very by individual and may be different for men and women, so it is important to recognize the signs. The most common signs include uncomfortable pressure, squeezing, fullness or pain in the center of the chest; pain or discomfort in one or both arms, your back, neck, jaw, or stomach; shortness of breath; breaking out in a cold sweat, nausea, or lightheadedness. If there is a history of heart disease in your family it may be helpful to know what types of symptoms other family members may have had.
Because oxygen is vital to the proper functioning of the body, and the heart is the pump that pushes the blood, with the oxygen around the body, any disfunction can have major complications. Thus, it is important to keep your heart healthy. And, hence the reminders during heart health month.
Image Credit: Used under license from 123RF – Sebnem Ragiboglu
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