Nigeria is back in the rainy season, that part of the year many senior citizens do not like. For asthmatics and arthritis- challenged persons, too, the weather may be too cold to handle, and unfriendly. The fields will soon green up and plant pollen, enemy of some persons with breathing difficulties, will soon fill the air. Arthritis pain may worsen in this season, too.
As for many senior citizens, their legs and feet may become so cold that they may appear lifeless. Blood hardly circulates in their legs. The leg muscles suffer painful cramps. Standing or sitting for too long, for want of something useful to do, old persons may suffer damage to the valves in the hand and leg veins. This may make blood to accumulate in these legs, causing gradual death in these legs from lack of oxygen and nutrients and poisoning by wastes and toxins.
Some old persons wear compression stockings to bed to keep their legs warm and blood flowing through them. They massage their legs with all sort of heat lotions. They do not walk well during the day as their legs are hardly able to bear their weight. Their troubles with their cold, heavy, painful and probably dying legs is called venous insufficiency. That means not all the blood the heart pumps to all parts of the body return to it to be refreshed and pumped out again. Why blood is pooling or hanging out in the legs instead of returning to the heart, thereby causing death by instalments in the legs, will gain the attention of this column from next Thursday (March 24, 2022).
Young citizens do not look forward to a life like this. Concidentally, Nigeria has set up a National Senior Citizen Centre to register all of its old citizens and make life more meaningful and comfortable for them. October 5 has also been declared a National Citizen Day, while a national policy on aging is in the offing.
From next Thursday, this column will contribute its widow’s mite to the care of senior citizen health in a series of articles on how to easily cope with or overcome venous insufficiency, as the afore- mentioned problems are called.
Today, Dr. Payal Kohli and Tim Newman will take the floor to educate us about how the heart works. It is the organ, which rest neither day nor night, pumping blood round the body and whose health conditions may impact the legs and the hands in various ways. In the second presentation, Colin Doyle will educate us about how disturbances in the heart negatively affect the hands and legs causing pain, cramps, swelling and heaviness, among others problems.
Structure of the heart
Medically reviewed by Dr. Payal Kohli, M.D., FACC — Written by Tim Newman — Updated on September 29, 2020: “The human heart is a finely-tuned instrument that serves the whole body. It is a muscular organ around the size of a closed fist, and it sits in the chest, slightly to the left of centre.
“The heart beats around 100,000 times a day, pumping approximately eight pints of blood throughout the body 24/7. This delivers oxygen- and nutrient-rich blood to tissues and organs and carries away waste.
“The heart sends deoxygenated blood to the lungs, where the blood loads up with oxygen and unloads carbon dioxide, a waste product of metabolism.
“Together, the heart, blood, and blood vessels — arteries, capillaries, and veins — make up the circulatory system.
In this article, we explore the structure of the heart, how it pumps blood around the body, and the electrical system that controls it.’’
Anatomy of the heart
Below is an interactive 3D model of the heart. Explore the model using your mouse pad or touchscreen to learn more.
The heart consists of four chambers:
The atria: These are the two upper chambers, which receive blood.
The ventricles: These are the two lower chambers, which discharge blood.
A wall of tissue called the septum separates the left and right atria and the left and right ventricle. Valves separate the atria from the ventricles.
The heart’s walls consist of three layers of tissue:
Myocardium: This is the muscular tissue of the heart.
Endocardium: This tissue lines the inside of the heart and protects the valves and chambers.
Pericardium: This is a thin protective coating that surrounds the other parts.
Epicardium: This protective layer consists mostly of connective tissue and forms the innermost layer of the pericardium.
How the heart works
The rate at which the heart contracts depends on many factors, such as:
- Activity and exercise
- Emotional factors
- Some medical conditions
- A fever
- Some medications
- Dehydration
At rest, the heart might beat around 60 times each minute. But this can increase to 100 beats per minute (bpm) or more.
Learn more information about a “normal” heart rate here.
Left and right sides
The left and right sides of the heart work in unison. The atria and ventricles contract and relax in turn, producing a rhythmic heartbeat.
Right side
The right side of the heart receives deoxygenated blood and sends it to the lungs.
The right atrium receives deoxygenated blood from the body through veins called the superior and inferior vena cava. These are the largest veins in the body.
The right atrium contracts, and blood passes to the right ventricle.
Once the right ventricle is full, it contracts and pumps the blood to the lungs via the pulmonary artery. In the lungs, the blood picks up oxygen and offloads carbon dioxide.
Left side
The left side of the heart receives blood from the lungs and pumps it to the rest of the body.
Newly oxygenated blood returns to the left atrium via the pulmonary veins. The left atrium contracts, pushing the blood into the left ventricle. Once the left ventricle is full, it contracts and pushes the blood back out to the body via the aorta.
Diastole, systole, and blood pressure
Each heartbeat has two parts:
Diastole: The ventricles relax and fill with blood as the atria contract, emptying all blood into the ventricles.
Systole: The ventricles contract and pump blood out of the heart as the atria relax, filling with blood again.
When a person takes their blood pressure, the machine will give a high and a low numberTrusted Source. The high number is the systolic blood pressure, and the lower number is the diastolic blood pressure.
Systolic pressure: This shows how much pressure the blood creates against the artery walls during systole.
Diastolic pressure: This shows how much pressure is in the arteries during diastole.
Gas exchange
When blood travels through the pulmonary artery to the lungs, it passes through tiny capillaries that connect on the surface of the lung’s air sacs, called the alveoli.
The body’s cells need oxygen to function, and they produce carbon dioxide as a waste product. The heart enables the body to eliminate the unwanted carbon dioxide.
Oxygen enters the blood and carbon dioxide leaves it through the capillaries of the alveoli.
The coronary arteries on the surface of the heart supply oxygenated blood to the heart muscle.
Pulse
A person can feel their pulse at points where arteries pass close to the skin’s surface, such as on the wrist or neck. The pulse is the same as the heart rate. When you feel your pulse, you feel the rush of blood as the heart pumps it through the body.
A healthy pulse is usually 60–100 bpmTrusted Source, and what is normal can vary from person to person.
A very active person may have a pulse as low as 40 bpm. People with a larger body size tend to have a faster pulse, but it is not usually over 100 bpm.
Valves
The heart has four valvesTrusted Source to ensure that blood only flows in one direction:
Aortic valve: This is between the left ventricle and the aorta.
Mitral valve: This is between the left atrium and the left ventricle.
Pulmonary valve: This is between the right ventricle and the pulmonary artery.
Tricuspid valve: This is between the right atrium and right ventricle.
Most people are familiar with the sound of the heart. In fact, the heart makes many types of sound Thrusted Source, and doctors can distinguish these to monitor the health of the heart.
The opening and closing of the valves are key contributors to the sound of the heartbeat. If there is leaking or a blockage of the heart valves, it can create sounds called “murmurs.”
The heart’s electrical system
To pump blood throughout the body, the muscles of the heart must work together to squeeze the blood in the right direction, at the right time, and with the right force. Electrical impulses coordinate this activity.
The electrical signal begins at the sino-atrial node, sometimes called the sinus, or SA, node. This is the heart’s pacemaker, and it sits at the top of the right atrium. The signal causes the atria to contract, pushing blood down into the ventricles.
The electrical impulse then travels to an area of cells at the bottom of the right atrium, between the atria and ventricles, called the atrioventricular, or AV, node.
These cells act as a gatekeeper. They coordinate the signal so that the atria and ventricles do not contract at the same time. There needs to be a slight delay.
From here, the signal travels along fibres, called Purkinje fibres, within the ventricle walls. The fibres pass the impulse to the heart muscle, causing the ventricles to contract.
Blood vessels
There are three types of blood vessels:
Arteries: These carry oxygenated blood from the heart to the rest of the body. The arteries are strong, muscular, and stretchy, which helps push blood through the circulatory system, and they also help regulate blood pressure. The arteries branch into smaller vessels called arterioles.
Veins: These carry deoxygenated blood back to the heart, and they increase in size as they get closer to the heart. Veins have thinner walls than arteries.
Capillaries: These connect the smallest arteries to the smallest veins. They have very thin walls, which allow them to exchange compounds such as carbon dioxide, water, oxygen, waste, and nutrients with surrounding tissues.
The heart, blood, and blood vessels make up the circulatory, or cardiovascular, system.
Here, learn about some diseases that can affect this system.
Cardiac arrest: When the heart stops
The heart is essential to life — if it stops beating, blood will not reach the brain and other organs, and the person can die within minutesTrusted Source. This is called cardiac arrest”
How Your Heart Health Impacts Your Leg Veins
By Colin Doyle, APRN
“Vein issues do not affect your heart health, but it’s important to recognise that a heart condition may make vein problems worse. If you suffer from a heart problem, you need to find out why your leg veins may be at risk for getting much worse.
February has been declared national heart health awareness month, providing an opportunity to discuss questions regarding cardiovascular disease and heart health. With this in mind, individuals diagnosed with vein disease are often concerned about possible cardiac implications. This concern stems from the condition’s pathology, which involves the breakdown of valves and the dilation of blood vessels, both of which reduce blood flow back to the heart and cause a pooling of blood in the lower extremities.
Does venous insufficiency damage the valves in my heart?
With venous insufficiency, the stress placed upon valves of veins is a result of gravitational pressure. Gravitational pressure is essentially neutral at the diaphragm (a large muscular partition at the base of the lungs). This pressure increases from that point to the foot. Luckily, the heart is just above the diaphragm, so gravity places no pressure on its valves.
Does the pooling of blood in the legs damage the heart?
Venous insufficiency is a chronic condition and the pooling of blood can result in increased pressure in the veins of the legs. This can cause discomfort that is often described as an ache, heavy pressure or cramping. The pressure can also cause the veins in the legs to bulge. Fluid that should be in the veins can leak into the surrounding tissue where it can cause swelling, colour variations and texture changes in the skin, and eventually even skin breakdown. The condition is chronic and occurs over time. The body accommodates for pooling of blood and plasma in the legs.
So, to sum up, venous insufficiency doesn’t affect the heart or cause heart problems to progress. On the other hand, existing heart problems, especially congestive heart failure, can make vein problems in the legs much worse depending on the degree of the heart issue. A heart that isn’t squeezing effectively can cause massive back pressure in the veins of the legs to the extent that fluid is pushed across the vein walls into the tissue, resulting in massive swelling of the legs.
This cardiac condition can be treated in several ways. All of these treatments need to be carefully supervised to ensure that further problems don’t arise and the patient’s ease of breather has been monitored. This is best done by a cardiologist. While the cardiologist is the person to follow heart functions and pumping efficiency, a vascular or general surgeon specialising in venous therapy is the best person to monitor leg therapy with compression and treatment of the underlying venous disorder.”