Mini Med School: Heart Disease

OBJECTIVES:

At the end of this class, you will be able to:

1. Discuss the role of the heart and the circulatory system.
   
2. List the signs of heart disease.
   
3. Describe some major heart disorders.
   
4. Care for the patient or resident with a heart disorder.

THE ROLE OF THE HEART AND THE CIRCULATORY SYSTEM

The heart is a very important organ. It is found in the middle of the chest and it is made up of muscle. It is hollow so that it can hold and pump blood from one part to the next and then to the body.

The heart has two (2) sides. They are called the left and the right side of the heart.

The heart has two (2) chambers on the top and two (2) chambers on the bottom. The left and right atriums are the chambers that are on the top of the heart. The left and right ventricles are found on the bottom of the heart.

The blood flows from the right atrium to the right ventricle. It then goes to the lungs and then to the left atrium and the left ventricle. Valves are found between the atrium and the ventricle on both sides and as the blood leaves both ventricles. They keep the blood flowing in one direction and prevent it from going backwards.

The heart sends oxygen rich blood to the entire body, including the heart muscle itself. The body cannot function correctly without enough oxygen. It would die.

The heart also gets rid of the body's waste, carbon dioxide. The heart collects oxygen poor blood with high amounts of carbon dioxide from the body. It then sends this blood to the lungs to pick up oxygen and to get rid of carbon dioxide before it sends this fresh supply of blood to the body with each beat of the heart.

During each beat of the heart, all of the chambers of the heart relax and then fill with blood. This period of rest is called diastole. Diastole pressure is measured when a person's blood pressure is taken. Diastole is the bottom number of the blood pressure reading. For example, if a person's blood pressure is 122/76, 76 is the pressure of the heart during rest, or diastole. When the diastolic blood pressure is high it means that the person's heart is working too hard when it is supposed to be resting.

After rest, each chamber contracts as it pumps blood. This period of work is called systole. Systole pressure is also measured when a person's blood pressure is taken. Systole is the top number of the blood pressure reading. For example, if a person's blood pressure is 122/76, the heart is working at a pressure of 122 during systole. A person's heart is working too hard when a person's systolic blood pressure is high.

The circulatory system is composed of:

• arteries,
  
• arterioles,
  
• capillaries,
  
• venules, and
  
• veins.
  

Arteries carry the oxygen rich blood away from the heart. They lead into the arterioles, which are smaller than arteries. The blood then goes to the capillaries. The capillaries pass oxygen and nutrients from the blood to the body and they pick up the waste products. This blood then goes into venules, which lead the blood back to the veins and then the heart. heart. Veins have thin walls and they are larger in diameter, or wider, than arteries. They carry the same amount of blood as arteries but at a lower speed and under much less pressure.

THE SIGNS OF HEART DISEASE

There are many signs of heart disease. Some people do not have any of these signs until the heart disease has become very severe. It is, therefore, important to have regular check ups with a doctor so that hidden or silent heart disease can be found and treated before it becomes a big problem to the person.

Some of the most common signs of heart disease are:

• Chest Pain. When muscles, like the muscles of the legs or the heart, do not get enough oxygen, waste products cause cramping and a condition called ischemia. For example, when a person exercises for a long time they may get a painful leg cramp. This cramp happens because the oxygen to the leg is not enough to feed the muscle during this exercise. The same thing happens to the heart itself. When the heart muscle does not get enough oxygen, a person will feel a cramping and pain in their chest.
  
  
• Shortness of breath. Shortness of breath is another sign of a heart problem. It is very common when the person has heart failure. Shortness of breath happens when fluid collects in the spaces of the lung where only air should be. This condition is similar to drowning. In the early stages of heart failure, the shortness of breath may happen only when the person is doing a lot of exercise. As the heart gets worse the person may become short of breath even when they are resting. It is usually worse when a person is lying down. Having the person sit up in a semi-Fowler's position often helps shortness of breath.
  
  
• Fatigue. Many people feel weak and tired when the heart is not sending enough oxygen to the body and the body parts.
  
  
• Heart palpitations. People do not feel their heart beating in their chest when their heart is normal, except when they are doing heavy exercise or they are very nervous or scared. People that have heart disease may often feel their heart beat. When a person feels their heart beat or pound in their chest, it is called palpitations.
  
  
• Lightheadedness and fainting. Lightheadedness and fainting can happen when a person's heart does not beat in a regular manner, when blood pressure is low and when the heart is not pumping in the right way.
  

MAJOR HEART DISORDERS

Some of the major heart disorders include:

• Hypertension
  
• Angina
  
• Heart attack
  
• Heart valve disorders
  
• Heart failure
  
  

Hypertension

Normally, infants and children have a lower blood pressure than adults. Blood pressure usually gets higher as a person gets older. Blood pressure is also normally higher when a person is exercising. It is normally lower when they are resting and lowest when the person is sleeping. Blood pressure can also be different at different times of the day. It is usually lowest during the night time hours and it gets higher as the morning comes.

High blood pressure (hypertension) is a common cardiac disorder. High blood pressure can lead to heart attack, stroke, kidney damage and other health problems.

Blood pressure can be high for a number of reasons. It will be high when:

• the heart is pumping with great force, or
  
• the arteries from the heart become narrow and stiff (atherosclerosis) and they do not expand normally when the blood flows through. This makes the heart work harder to move the blood along, or
  
• there is far too much fluid in the circulatory system, as is the case when a person's kidneys are not working the way they should.
  
  

High blood pressure can be caused by:

• kidney problems, including tumors and infections,
  
• hormone disorders,
  
• some medications, like oral birth control pills,
  
• alcohol abuse,
  
• smoking,
  
• drug abuse,
  
• poor eating habits that increase cholesterol and triglycerides,
  
• other causes, such as pregnancy and lead poisoning, and
  
• unknown reasons.
  
  

It is also possible that high blood pressure can be caused by stress over long periods of time, a high amount of salt in the diet, a lack of exercise and being over your ideal weight.

As many as 50 million Americans have high blood pressure. Blood pressure is considered high when:

• the systolic blood pressure is more than 140 at rest, and/or
  
• the diastolic blood pressure is 90 or more at rest.
  
  

Most people with hypertension have both a high diastolic and a high systolic blood pressure. (Merck & Co, Inc., 1995- 2003).

A person can lower their high blood pressure by NOT using alcohol or cigarettes, by eating foods low in salt and cholesterol and by managing their stress.

Exercise and a healthy weight are also important in keeping the blood pressure at a good level. A patient's doctor may order medications, such as a diuretic (water pill) and/or a cardiac medication to lower a person's blood pressure things, like diet and exercise, do not lower the person's blood pressure.

Some people may not have any signs of high blood pressure. Others do. Some of the signs of high blood pressure are:

• a headache,
  
• nosebleeds,
  
• nausea,
  
• vomiting
  
• dizziness,
  
• shortness of breath,
  
• a flushed face,
  
• restlessness
  
• fatigue, and
  
• blurry vision.
  
  

Angina

This condition happens when the insides of the arteries that nourish the heart muscle itself (coronary arteries) become too narrow for the oxygen rich blood to feed them. They get narrow when fatty deposits build up on the inside of these arteries. This build up and narrowing is called atherosclerosis.

Angina and a heart attack occur when the narrowing of the coronary arteries becomes severe. A person with angina will have chest pressure and pain when the heart muscle is not getting enough oxygen.

Coronary artery disease is most common among people who:

• eat a high-fat diet,
  
• smoke, and
  
• do not exercise.
  
  

Again, some people do not have the signs of angina. They have what is called "silent ischemia". Others, however, do have signs. The signs of angina include:

• pressure or pain under the breast bone,
  
• left shoulder pain,
  
• pain down the inside of the left arm, and
  
• sometimes pain in the jaw, teeth, throat, back and even the right arm.
  
  

Some people have angina pain only with activity. Others have angina pain even at rest. When a person has angina pain with activity, they should rest. Some people have more pain when the weather is cold, when they are under stress or after they have just finished a meal.

The treatment of angina often involves the use of several medications, including nitroglycerine, which the person places under their tongue during an attack. Some people will also get bypass surgery or angioplasty to repair damaged coronary arteries.

Heart Attack

Heart attack, also known as myocardial infarction, is when the oxygen supply to the heart is suddenly cut off, thus causing the heart muscle itself, and the person, to die unless treated immediately. An irregular heart beat during a heart attack can lead to cardiac arrest unless it can be treated. A heart attack is a medical emergency. It needs immediate treatment. People who live in their own homes should be told to call for 911 as soon as the symptoms of a heart attack begin.

The risk of heart disease and heart attack increases with high levels of LDL, or bad cholesterol. And, the risk of heart disease decreases with high HDL, or good cholesterol. A person with low LDL and high HDL is less likely to have heart disease than a person with high LDL and low HDL.

Heart attacks most often happen when a coronary artery is cut off by a blood clot in a narrowed vessel. The signs of a heart attack are:

• shortness of breath, chest pain and a feeling of fatigue, sometimes for days before the heart attack,
  
• chest pain that spreads to the left arm, back and/or jaw and/or even the right arm,
  
• stomach pain that the person may think is just indigestion,
  
• feeling faint,
  
• heavy palpitations or pounding of the heart,
  
• sweating,
  
• restlessness,
  
• loss of consciousness,
  
• disorientation,
  
• a blue color on the lips, feet and/or hands.
  
  

Like angina, some people having a heart attack have no signs or symptoms at all. These heart attacks are called "silent heart attacks".

Heart attacks are treated with rest, oxygen, a number of different medications, including aspirin, which thins the blood, and pain medications to help the pain and to ease the amount of work that the heart has to do as a result of the pain.

The person will also get medications to prevent constipation and a urinary catheter, if needed. Some doctors order one baby aspirin a day to lower the risk of future heart attacks.

People who have had a heart attack are usually up in the chair after a couple of days. After, they will begin progressive activity and cardiac rehabilitation. Many will also be instructed to change some things in their life. For example, they may be told to stop smoking, to lose some weight and to get some regular exercise.

Heart Valve Disorders

The heart has four (4) valves. They are the:

• the tricuspid valve which is between the right atrium and the right ventricle,
  
• the pulmonary valve which is between the right ventricle and the pulmonary arteries,
  
• the mitral valve which is between the left atrium and the left ventricle, and
  
• the aortic valve, which is between the left ventricle and the aorta.
  
  

These heart valves can sometimes leak or fail to open correctly. When a valve leaks, it is called regurgitation. When a valve does not open in the right way, it is called stenosis. For example, when the mitral valve leaks it is called mitral valve regurgitation. And, when the pulmonary valve does not open correctly, it is called pulmonary stenosis. Some heart valve disorders are present when a person is born. Others can be caused by an infection, like rheumatic fever.

Surgery is done to repair a valve that is not working well enough to keep the person in good health. A pig valve or a mechanical valve is placed in the person’s heart to replace the valve that is not working well.

Heart Failure

Heart failure is also called congestive heart failure. Heart failure is a very serious condition. The oxygen and nutrients pumped by the heart is not enough to keep the body and its parts in proper condition. The heart can not keep up with the body’s demands. It is found more often among the elderly.

This cardiac disorder can be caused by a number of things, such as:

• coronary artery disease,
  
• heart valve disease,
  
• high blood pressure
  
• myocarditis, an infection of the heart muscle, and
  
• irregular beating of the heart
  
  

Some of the signs of heart failure are:

• fatigue
  
• swelling of the feet, ankles, abdomen and liver (right sided heart failure)
  
• fluid buildup in the lungs and shortness of breath (left sided heart failure)
  
  

This heart disorder is treated by treating the cause of it, by taking away some of the things that make the disorder worse, like losing weight, stopping smoking and lowering the amount of salt, or sodium, in the diet.

Nursing assistants who are asked to take care of people with heart failure may be asked to:

• Limit the amount of fluids that the person gets.
  
• Give the person a low salt diet. Salt holds water and fluids. A low salt (low sodium) diet is often given to the person with heart failure in order to lower the amount of fluid in a person's body. This special diet is usually ordered by the doctor in terms of how many milligrams (mg) of sodium the person may have during the course of the entire day.
  
• Take daily body weights. These weights should be done in the morning before breakfast, after the person has voided and using the same scale. A gain of 2 or more pounds in one day means that the person is building up body fluid. It must be reported to the nurse.
  
• Measure intake and output.
  
• Position the person in a sitting position when they are short of breath.
  
• Elevate the person's leg when they have fluid build up (edema).
  
  

When salt restriction alone doesn't reduce fluid retention, a doctor may prescribe diuretic, or water, pills.

SUMMARY

Heart disease is a very common problem in our country, especially among the elderly. Nursing assistants play a very important role in caring for these patients and residents. They provide direct care and observe the patient for signs of heart disease. All observations, especially those that indicate a medical emergency, like chest pain, must be reported to the nurse.

REFERENCES

American Heart Association. (2001). Heart Attack. http://www.americanheart.org/presenter.jhtml?identifier=4578

Merck & Company, Inc.(1999). Cardiovascular Disorders. The Merck Manual of Diagnosis and Therapy, Seventeenth Edition. http://www.merck.com/pubs/mmanual/section16/sec16.htm

Merck & Company, Inc.(1995 – 2003).Coronary Artery Disease. The Merck Manual of Medical Information- Home Edition. http://www.merck.com/mrkshared/mmanual_home/sec3/27.jsp

Merck & Company, Inc.(1995 – 2003). Heart and Blood Vessel Disorders. The Merck Manual of Medical Information- Home Edition. http://www.merck.com/mrkshared/mmanual_home/sec3/14.jsp

Merck & Company, Inc.(1995 – 2003). Heart Attack. The Merck Manual of Medical Information- Home Edition. http://www.merck.com/mrkshared/mmanual_home/sec3/27.jsp

Merck & Company, Inc.(1995 – 2003). Heart Failure. The Merck Manual of Medical Information- Home Edition. http://www.merck.com/mrkshared/mmanual_home/sec3/17.jsp

Merck & Company, Inc.(1995 – 2003). High Blood Pressure. The Merck Manual of Medical Information- Home Edition. http://www.merck.com/mrkshared/mmanual_home/sec3/25.jsp

Copyright © 2003 Alene Burke