CAD	Coronary artery disease
CDC	Centers for Disease Control and Prevention
CO₂	Carbon dioxide
COPD	Chronic obstructive pulmonary disease
MI	Myocardial infarction
mm Hg	Millimeters of mercury
O₂	Oxygen
TB	Tuberculosis

Cardiovascular and respiratory system disorders are leading causes of death in the United States. Many people have these disorders. Refer to Chapter 9 while you study this chapter.

Cardiovascular disorders

Problems occur in the heart or blood vessels. See Chapter 35 for circulatory ulcers. Risk factors for cardiovascular disorders are listed in Box 40-1.

Box 40-1

Risk Factors for Cardiovascular Disorders

Hypertension

Factors you cannot change

• Age—45 years or older for men; 55 years or older for women

• Gender—younger men are at greater risk than younger women; the risk increases for women after menopause

• Race—African-Americans are at greater risk than whites

• Family history—tends to run in families

Factors you can change

Coronary artery disease

Factors you cannot change

• Gender—men are at greater risk than women

• Age—in men, the risk increases after age 45; in women, the risk increases after age 55

• Family history

• Race—African-Americans are at greater risk than other groups

Factors you can change

• Being over-weight

• Lack of exercise

• High blood cholesterol

• Hypertension

• Smoking

• Diabetes

Hypertension

With hypertension (high blood pressure), the resting blood pressure is too high. The systolic pressure is 140 mm Hg (millimeters of mercury) or higher (hyper). Or the diastolic pressure is 90 mm Hg or higher. Such measurements must occur several times. Pre-hypertension is when the systolic pressure is between 120 and 139 mm Hg or the diastolic pressure is between 80 and 89 mm Hg. The person with pre-hypertension will likely develop hypertension in the future. Most people have hypertension some time during their lives. See Box 40-1 for risk factors.

Narrowed blood vessels are a common cause. The heart pumps with more force to move blood through narrowed vessels. Kidney disorders, head injuries, some pregnancy problems, and adrenal gland tumors are causes.

A person can be unaware of hypertension for many years. That is why hypertension is called “the silent killer.” Hypertension is found when blood pressure is measured. Signs and symptoms develop over time. Headache, blurred vision, dizziness, and nose bleeds occur. Hypertension can lead to stroke, hardening of the arteries, heart attack, heart failure, kidney failure, and blindness.

Life-style changes can lower blood pressure. A diet low in fat and salt, a healthy weight, and regular exercise are needed. No smoking is allowed. Alcohol and caffeine are limited. Managing stress and sleeping well also lower blood pressure. Certain medications lower blood pressure.

Coronary artery disease

The coronary arteries are in the heart. They supply the heart with blood. In coronary artery disease (CAD), the coronary arteries become hardened and narrow. One or all are affected. The heart muscle gets less blood and oxygen (O₂). CAD also is called coronary heart disease and heart disease.

The most common cause is atherosclerosis (Fig. 40-1). Plaque—made up of cholesterol, fat, and other substances—collects on artery walls. The narrowed arteries block blood flow. Blockage may be total or partial. Blood clots can form along the plaque and block blood flow.

Fig. 40-1 A, Normal artery. B, Plaque on the artery wall in atherosclerosis.

The major complications of CAD are angina, myocardial infarction (heart attack), irregular heartbeats, and sudden death. The more risk factors, the greater the chance of CAD and its complications. See Box 40-1 for risk factors.

CAD can be treated. Treatment goals are to:

• Relieve symptoms (see “Angina”)

• Slow or stop atherosclerosis

• Lower the risk of blood clots

• Widen or bypass clogged arteries

• Reduce cardiac events (see “Angina” and “Myocardial Infarction,” p. 620)

Persons with CAD need to make life-style changes. The person must quit smoking, exercise, and reduce stress. A healthy diet is needed to reduce high blood pressure, lower blood cholesterol, and maintain a healthy weight. If over-weight, the person must lose weight.

Some persons need medications to decrease the heart’s workload and relieve symptoms. Other medications are given to prevent a heart attack or sudden death. Medications can delay the need for medical and surgical procedures that open or bypass diseased arteries (Fig. 40-2).

Fig. 40-2 Triple coronary artery bypass surgery. (Modified from Thibodeau GA, Patton KT: *The human body in health & disease,* ed 5, St Louis, 2010, Mosby.)

See Focus on Rehabilitation: Coronary Artery Disease.

FOCUS ON REHABILITATION

Coronary Artery Disease

Persons with complications from CAD may need cardiac rehabilitation (cardiac rehab). The cardiac rehab team includes doctors (the person’s doctor, a heart specialist, a heart surgeon), nurses, exercise specialists, physical and occupational therapists, dietitians, and mental health professionals.

Cardiac rehab has two parts:

• Exercise training. The person learns to exercise safely. Exercises are done to strengthen muscles and improve stamina (staying power, endurance). The exercise plan is based on the person’s abilities, needs, and interests.

• Education, counseling, and training. The person learns about:

• His or her heart condition

• How to reduce the risk of future problems

• How to adjust to a new life-style

• How to deal with fears about the future

Angina

Angina (pain) is chest pain from reduced blood flow to part of the heart muscle (myocardium). It occurs when the heart needs more O₂. Normally blood flow to the heart increases when O₂ needs increase. Exertion, a heavy meal, stress, and excitement increase the heart’s need for O₂. So does smoking and very hot or cold temperatures. In CAD, narrowed vessels prevent increased blood flow.

Chest pain is described as a tightness, pressure, squeezing, or burning in the chest (Fig. 40-3, p. 620). Pain can occur in the shoulders, arms, neck, jaw, or back. Pain in the jaw, neck, and down one or both arms is common. The person may be pale, feel faint, and perspire. Dyspnea is common. Nausea, fatigue, and weakness may occur. Some persons complain of “gas” or indigestion. Rest often relieves symptoms in 3 to 15 minutes. Rest reduces the heart’s need for O₂. Therefore normal blood flow is achieved. Heart damage is prevented.

Fig. 40-3 *Shaded areas* show where the pain of angina is located. (From Lewis SM, Heitkemper MM, Dirksen SR: *Medical-surgical nursing: assessment and management of clinical problems,* ed 7, St Louis, 2007, Mosby.)

Besides rest, a nitroglycerin tablet is taken when angina occurs. It is placed under the tongue. There it dissolves and is rapidly absorbed into the bloodstream. Tablets are kept within the person’s reach at all times. The person takes a tablet and then tells the nurse. Some persons have nitroglycerin patches. The nurse applies and removes them.

Things that cause angina are avoided. These include over-exertion, heavy meals and over-eating, and emotional stress. The person needs to stay indoors during cold weather or during hot, humid weather. Doctor-supervised programs are helpful.

See “Coronary Artery Disease” for the treatment of angina. The goal is to increase blood flow to the heart. Doing so may prevent or lower the risk of heart attack and death. Chest pain lasting longer than a few minutes and not relieved by rest and nitroglycerin may signal heart attack. The person needs emergency care.