The heart, in a human body, may be as small as a fist, but its function is great. It is the heart that pumps “blood through the circulatory system by rhythmic contraction and dilation.” If the heart stops pumping enough blood to any part of the body, stroke occurs. If the heart stops working, death occurs.
The heart is an important organ in the body that must be healthy. It is therefore inevitable to healthy heart. For those who don’t pay attention to their heart matter, the doctor mince no word in saying the consequences could be too grievous.
Weighing between seven and 15 ounces (200 to 425 grams), the heart beats an average of 100, 000- times daily, pumping about 7, 571 litres of blood. In one’s lifetime, one’s heart may have beat more than 3.5 billion times.
The heart is located between the lungs, at the middle of the chest, “behind and slightly to the left of your breastbone (sternum).”
According to the Texas Heart Institute, there is “a double-layered membrane called the pericardium” surrounding the heart like a sac. “The outer layer of the pericardium surrounds the roots of your heart’s major blood vessels and is attached by ligaments to your spinal column, diaphragm, and other parts of your body. The inner layer of the pericardium is attached to the heart muscle. A coating of fluid separates the two layers of membrane, letting the heart move as it beats,” the institute said in a publication on texasheart.org.
On the anatomy of the heart, the institute said: “Your heart has four chambers. The upper chambers are called the left and right atria, and the lower chambers are called the left and right ventricles. A wall of muscle called the septum separates the left and right atria and the left and right ventricles. The left ventricle is the largest and strongest chamber in your heart. The left ventricle’s chamber walls are only about a half-inch thick, but they have enough force to push blood through the aortic valve and into your body.”
How the heart works
Tanya Lewis, in a paper, “Human Heart: Anatomy, Function & Facts,” published in livescience.com, underlines the way the heart works, in performing its duty of pumping blood to all parts of the body.
According to Lewis, the “heart circulates blood through two pathways: the pulmonary circuit and the systemic circuit. In the pulmonary circuit, deoxygenated blood leaves the right ventricle of the heart via the pulmonary artery and travels to the lungs, then returns as oxygenated blood to the left atrium of the heart via the pulmonary vein.
“In the systemic circuit, oxygenated blood leaves the body via the left ventricle to the aorta, and from there enters the arteries and capillaries where it supplies the body’s tissues with oxygen. Deoxygenated blood returns via veins to the venae cavae, re-entering the heart’s right atrium.”
Lewis quoted Dr. Lawrence Phillips, a cardiologist at NYU Langone Medical Center, in New York, the United States, as saying blockage of any of these arteries can cause a heart attack or damage to the muscle of the heart.
“A heart attack is distinct from cardiac arrest, which is a sudden loss of heart function that usually occurs as a result of electrical disturbances of the heart rhythm. A heart attack can lead to cardiac arrest, but the latter can also be caused by other problems,” he quoted Dr. Phillips as saying.
Lewis wrote that a healthy heart contraction happens in five stages. “In the first stage (early diastole), the heart is relaxed. Then the atrium contracts (atrial systole) to push blood into the ventricle. Next, the ventricles start contracting without changing volume. Then the ventricles continue contracting while empty. Finally, the ventricles stop contracting and relax. Then the cycle repeats,” he said.
An unhealthy heart
A consultant cardiologist and Medical Director of United Heart Hospital and Clinics, Eugene Azubuike Nwosu, said heart-related ailments, also known as cardiovascular disease, was the second leading cause of death globally.
He identified some of the risk factors for heart disease to be: Eating poorly; old age; high blood pressure; diabetes, irregular physical exercise, high cholesterol in the body, smoking, family history, stress, pollution and poor dental hygiene.
Dr. Nwosu gave assurance that when certain precautions are taken, the risk factors could be minimised or eliminated, insisting that the key to overcoming cardiovascular infections was eating the right foods and avoiding sedentary lifestyle.
He said the major problems associated with the heart were the Coronary Artery disease (CAD) – the build-up of plague that clogs up the inside of blood vessels supplying blood to the heart muscles.
He said CAD affects all, with no respect to race, nationality or gender, adding that it is the commonest cause of sudden death.
He said: “Most sudden death in Nigeria is not Juju; it is heart attack. The incidence in Nigeria and the developing world is on the rise because of several factors, including changing life styles and diet, increasing obesity and diabetes epidemics among others.
“In order to reduce the incidence, we must recognise the risk factors and take action to modify those risks. The more the number of risk factors someone has, the higher his or her risk of developing the disease.”
Coronary artery disease
Experts say family background/history, age, weight/obesity, hypertension, smoking, diabetes, and sedentary lifestyle could cause heart diseases.
Research shows that a person, whose sibling, parents or grandparents have had early heart attacks by age 55, for male relatives and age of 65 for female relatives, is at increased risk of heart disease.
One age, heart diseases increase in men from age 45 or older and for women age 55 or older, but very high in elderly population of 75 and older.
Dr. Nwosu said: “Incidence of CAD is higher in males but women’s risk increase after menopause, when the protective effect of estrogen is lost.”
Hypertension: This is a significant risk. It occurs at younger age in people of African descents and is often more severe. It is a silent killer because in most people, it does not have any symptoms. It is imperative that the diagnosis is made and appropriate treatment to goal is achieved.
Smoking: Direct smoking and long-term exposure to second-hand smoke increase the risk of heart attack. Smoking increases blood pressure, decreases exercise tolerance and increases the tendency for blood to clot. It also increases the risk of recurrent coronary heart disease after bypass surgery.
“Cigarette smoking is the most important risk factor for young men and women; it produces a greater relative risk in persons under age 50 than in those over 50. Women who smoke and use oral contraceptives greatly increase their risk of coronary heart disease and stroke compared with non-smoking women who use oral contraceptives,” Nwosu said.
Obesity: too much weight or fat increases risk of heart disease. In obesity, where you carry your fat, is very important. Apple shape has excess fat on the abdomen and has significant correlation with metabolic syndrome. Pear shape has lower body fat with excess fat on the thighs and buttocks. It has no significant correlation with metabolic syndrome.
One good advice therefore is eating an apple but do not become one. Obesity is associated with high cholesterol, high triglyceride and diabetes. Losing 10 per cent of your body weight can lower your risk.
Sedentary lifestyle: Lack of exercise and physical activity increase the risk of heart attack. Persons that are out of shape do poorly after heart attack and take longer to recover. Physical inactivity identifies people who do not get the recommended level of regular physical activity. Regular physical activity reduces the risk of dying prematurely from CAD. It helps to prevent development of diabetes and to maintain weight loss and reduces hypertension.
Dr. Nwosu explained that the small plaque build-up that occupies less than 70 per cent of the cross-sectional area of the coronary vessels typically have no symptoms, but are the usual cause of sudden cardiac death (cardiac arrest) and acute heart attack by the process of plaque rupture.
He said: “Plaque build-up of greater than 70 per cent of the cross sectional area of the coronary arteries can cause angina, which is defined as chest pain, tightness or heaviness that is brought on by exertion. Emotion stress can also cause angina. Other names that are used to describe coronary artery disease are heart attack, myocardial infarction, angina, atherosclerosis and cardiovascular disease.
“The effects of plaque build-up are that, sometimes its significant plaque over the years may affect coronary vessels depriving the heart muscles adequate supply of blood and nutrients. This results in weak heart muscles and heart failure.’
Food and heart failure
When Hippocrates said, in 400BC: “Let food be your medicine and medicine be your food,” he was stating the importance of food to the body. It is not surprising, therefore, that Nwosu is advising Nigerians to avoid poor diet, especially high fat, high cholesterol diet. He stressed the need to eat right and take note of what one eats.
In his words: “Traditional western diets promote inflammation and are toxic to our bodies. There are high in salt, simple sugars, processed food with preservatives, bad fat and low on magnesium and potassium. Our consumption of such diet has a lot to do with increased trend of obesity, hypertension, diabetes, stroke, heart disease and death.
“The best diet proved to decrease heart attack and CAD is Mediterranean diet: a lifestyle that includes food (colourful fruits, vegetables, whole grain bread and pasta, omega-3- rich seafood) activities, meals with friends and family and wine in moderation with meals.
“Several studies have shown that those following a traditional Mediterranean diet suffer significantly less heart disease and death from heart attack compared to those following traditional American diet. Mediterranean diet is very low in saturated fat and contains no trans-fat,” Dr. Nwosu said.
He warned against sugar cereal, potato chips, French fries, grilled steak, cheese cake, butter, soda, and high omega-6 fat diet. Omega-6 fat, according to him, is bad fat and found in vegetable oil and red meat. It promotes inflammation whereas omega-3 fat found in walnuts, flaxseed, and fish is good fat and anti-inflammatory.
Processed foods are also not good for the heart, as, according to experts, they “have been stripped of their healthful ingredients and are loaded with artificial preservatives. They contain excessive amounts of unhealthy fats, refined sugar and sodium.”
Consumption of red meat, which is meat preserved by smoking, curing, salting or addition of chemical preservatives, should be reduced, to keep the heart healthy, as it is high in saturated fats, which raise bad cholesterol. It is and is high in Omega 6 fatty acid, which promotes inflammation. Fish, poultry or turkey several times per week is better.
Steps for better heart health
Dr. Nwosu recommended the following steps to ensure a healthy heart:
• Exercise of 10-minute walk: Physical activities aimed at generating heat in the body, like jogging, cycling and press-up help the heart to work better. However, when there is no time for exercise, a brief walk, clapping and marching are a great way to start. If you do, it’s a good way to add more exercise to your day.
• Give yourself a lift: Lifting a hardcover book or a two-pound weight a few times a day can help tone your arm muscles. When that becomes a breeze, move on to heavier items or join a gym.
• Eat one extra fruit or vegetable a day: Fruits and vegetables are inexpensive, taste good, and are good for everything from your brain to your bowels. Start the day with some fruit and a serving of whole grains, like oatmeal, bran flakes, or whole-wheat toast.
• Have a handful of nuts: Walnuts, almonds, peanuts, and other nuts are good for your heart. Try grabbing some instead of chips or cookies when you need a snack. Adding them to salads for a healthful and tasty crunch, or using them in place of meat in pasta and other dishes is good.
• Sample the fruits of the sea: Eat fish or other types of seafood instead of red meat once a week. It’s good for the heart, the brain, and the waistline.
• Breathe deeply: Try breathing slowly and deeply for a few minutes a day. It can help you relax. Slow, deep breathing may also help lower blood pressure.
• Wash your hands often: Scrubbing up with soap and water often during the day is a great way to protect your heart and health. The flu, pneumonia, and other infections can be very hard on the heart.
source : sun