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Part 2 book presents the following contents: Heart failure, heart muscle disease, heart rhythm disorders, peripheral vascular disease, stroke, women and heart disease, heart disease in the young, heart disease in the elderly, cardiovascular drugs, coronary angioplasty and interventional cardiology,...
CHAPTER 14 HEART FAILURE ROBERT SOUFER, M.D The heart’s primary function is to pump blood to all parts of the body, bringing nutrients and oxygen to the tissues and removing waste products When the body is at rest, it needs a certain amount of blood to achieve this function During exercise or times when greater demands are placed on the body, more blood is required To meet these variable demands, the heartbeat increases or decreases, and blood vessels dilate to deliver more blood or constrict during times when less blood is required When a person is diagnosed with heart failure, it does not mean the heart has stopped working, but rather that it is not working as efficiently as it should In other words, the term “failure” indicates the heart is not pumping effectively enough to meet the body’s needs for oxygen-rich blood, either during exercise or at rest The term congestive heart failure (CHF) is often synonymous with heart failure but also refers to the state in which decreased heart function is accompanied by a buildup of body fluid in the lungs and elsewhere Heart failure may be reversible, and people may live for many years after the diagnosis is made (See box, “Classifications of Heart Failure.”) Heart failure may occur suddenly, or it may develop gradually When heart function deteriorates over years, one or more conditions may exist, (See box, “Effects of Heart Failure.”) The strength of muscle contractions may be reduced, and the ability of the heart chambers to fill with blood may be limited by mechanical problems, resulting in less blood to pump out to tissues in the body Conversely, the pumping chambers may enlarge and fill with too much blood when the heart muscle is not strong enough to pump out all the blood it receives In addition, as the architecture of the heart changes as it enlarges, regurgitation of the mitral valve may develop, making the heart failure even worse WHO DEVELOPS HEART FAILURE? There are an estimated million people in the United States with heart failure The incidence of chronic congestive heart failure—the number of new cases developing in the given population each year—has increased in recent years This is possibly a result of the overall decline in deaths from coronary (ischemic) heart disease, an improvement attributed to medical advances and the fact that people are living longer The most common cause of congestive failure is coronary artery disease—narrowing of the arteries supplying blood to the heart muscle Although coronary disease often starts at an early age, congestive failure occurs most often in the elderly Among people more than 70 years old, about out of 1,000 are diagnosed with congestive heart failure each year The majority of these patients are women, probably because men are more likely to die from coronary artery disease before it progresses to heart failure Heart failure is also associated with untreated hypertension, alcohol abuse, and drug abuse (primarily cocaine and amphetamines) at any age Hyperthyroidism and various abnormalities of the heart valves (particularly aortic and mitral) are among the 177 MAJOR CARDIOVASCULAR DISORDERS Classifications of Heart Failure The New York Heart Association developed a system that has been used for many” years to provide a standardized set of criteria for the classification of heart failure based on the severity of the condition This is evaluated by symptoms and ability to function ● ● ● ● Class I: no undue symptoms associated with ordinary activity and no limitation of physical activity Class II: slight limitation of physical activity; patient comfortable at rest Class III: marked limitation of physical activity; patient comfortable at rest Class IV: inability to carry on any physical activity without discomfort; symptoms of cardiac insufficiency or chest pain possible even at rest Effects of Heart Failure Strength of muscle contractions is reduced ● Ability of the heart chambers to fill with blood is limited, so there is less blood to pump out to tissues in the body ● The pumping heart chambers fill with too much blood; the heart muscle is not strong enough to pump out all the blood it receives ● down, the quantity of blood pumped is less than adequate, and the pressure rises in the chambers of the heart, causing blood that is returning to the heart to back up in the lungs or veins Excessive fatigue may bean early symptom (See box, “Symptoms of Heart Failure.”) Some excess fluid may be forced out of the blood vessels into the body’s tissues It then settles in the feet, ankles, and legs, and sometimes also in the abdomen and liver Dyspnea, or shortness of breath, resulting from increased pressure, fluid, or both in the lungs, is a common symptom of congestive heart failure Although breathlessness is most likely to be noticed during exercise (known as dyspnea on exertion, or DOE), it can also be a problem at rest, particularly when the patient is lying down (when it is known as orthopnea) Individuals with orthopnea find that the condition feels worse when they are in a reclining position because the backflow of fluid and buildup in pressure from the heart interferes directly with the free flow of oxygen in the lungs Normally, oxygen is easily exchanged through the thin spongy tissue of the lungs (See Figure 14.1.) If this tissue becomes waterlogged, as it does in heart failure, less oxygen can be transferred to the blood If there is not enough oxygen, certain reflexes stimulate faster breathing People with lung congestion as a result of heart failure usually have to prop themselves up with extra pillows in order to sleep The number of pillows used may indicate to a physician the extent of the heart failure When an individual wakes at night because of shortness of breath from Svmntoms of Heart Failure other disorders that can cause heart failure In addition, viral infection or inflammation of the heart (myocarditis) or primary heart muscle disease (cardiomyopathy), and in rare instances, extreme vitamin deficiencies, can result in heart failure (See Chapters 13 and 15.) SIGNS AND SYMPTOMS Depending on the underlying causes, heart failure can be either acute (intense but not long-lasting) or chronic (protracted over a long time), When heart failure occurs, the forward flow of blood is slowed Shortness of breath (dyspnea) Shortness of breath when lying down (orthopnea) Shortness of breath while sleeping (paroxysmal or intermittent nocturnal dyspnea) Buildup of fluid in the lungs (pulmonary edema), frequently causing a person to cough up blood-tinged sputum Buildup of excess fluid (edema) in other parts of the body, causing weight gain, swelling of the ankles, legs, and back, and in extreme cases fluid accumulation in the abdomen (ascites) Fatigue, weakness, and an inability to exert oneself physically or mentally Blueness of the skin (cyanosis) HEART FAILURE When a marked excess of fluid accumulates in the lungs, it is known as pulmonary (lung) edema This condition is often, but not always, acute and is frequently associated with coughing up blood-tinged, pinkish-colored sputum Inefficient circulation may also manifest itself as fatigue, weakness, and an inability to exert oneself physically or mentally because less blood and oxygen reach the brain Older people in particular may suffer from confusion and impaired thinking ability LEFT SIDE OR RIGHT SIDE? Figure 14.1 This diagram of an alveolus (air sac) shows the exchange of carbon dioxide (CO2) and oxygen in the lung fluid settling in the lungs, the condition is known as paroxysmal (intermittent) nocturnal dyspnea A person suffering from this typically will wake up short of breath about two to three hours after going to sleep, Standing or sitting often relieves symptoms One of recent history's most noted patients with heart failure was President Franklin Delano Roosevelt He had severe hypertension that led to an enlarged heart and eventually to heart failure For months, he was unable to lie flat in bed, so he slept in a chair He was told that he had bronchitis, allergies, and the flu Finally, the right diagnosis was made and treatment started However, this was before the development of effective drugs to lower blood pressure and to treat advanced heart failure At the time of President Roosevelt’s death of a massive stroke on April 12, 1945, his blood pressure ranged between 180/110 and 230/130 The infiltration of the body with fluid can cause more than breathing problems and sleepless nights Patients may weigh more, because of the excess water retention, and they may have edema (swelling) of the skin and soft tissues, usually in the feet, ankles, or legs, and sometimes in the lower back This swelling is characterized by a gradual filling out after the area is depressed with a finger (See Figure 14.2.) In extreme cases, fluid will accumulate in the abdomen This is called ascites and is caused when swelling of the gastrointestinal tract forces fluid through the capillaries into the abdominal cavity Ascites usually occurs only in severe chronic heart failure The particular symptoms that an individual experiences are determined by which side of the heart is involved in the heart failure (See box, “Symptoms of Left-Side and Right-Side Heart Failure.”) For example, the left atrium (upper chamber) receives oxygen- Figure 14.2 Edema is swelling of the extremities caused by excess fluid buildup A sign of edema in the ankles is an indentation that remains momentarily when a finger is pressed into the skin and then removed 179 MAJOR CARDIOVASCULAR DISORDERS Symptoms of left-side heart failure ● Fatigue ● Shortness of breath (dyspnea) • Shortness of breath when lying down (othopnea) ● ● Paroxysmal (intermittent) nocturnal dyspnea Accumulation of fluid in the lungs (pulmonary edema), frequently causing a person to cough up blood-tinged sputum Symptoms of right-side heart failure • Swelling (edema) Dependent edema (edema that travels by gravity to the lowest portions of the body) Enlargement or swelling of the liver (hepatomegaly) Buildup of fluid in the abdominal cavity pendent (edema that travels by gravity to the lowest portions of the body), edema that results in enlargement or swelling of the liver (called hepatomegaly), ascites, and edema of the skin or soft tissues (only in some cases) Because congestive heart failure causes the body to fill with excess fluids, the kidneys may not be able to dispose of the extra sodium (a component of salt) and water, a condition known as kidney failure (Again, the term “failure” implies that the kidneys have failed and will not recover However, as in the case of heart failure, the kidney changes maybe temporary, and proper treatment may correct much of the problem.) Sodium that would normally be eliminated through the urine remains in the body, causing it to retain even more water, thereby aggravating the problem of excess fluid associated with congestive heart failure (ascites) Edema of the skin and soft tissues, causing swelling of the feet, ankles, and legs ● Excessive urination at night caused by fluid redistribution while a person is sleeping lying down (nocturia) ated blood from the lungs and passes it onto the left ventricle (lower chamber), which pumps it to the rest of the body When the left side isn’t pumping efficiently, blood backs up in the vessels of the lungs, and sometimes fluid is forced out of the lung vessels and into the breathing spaces themselves This pulmonary congestion causes shortness of breath The other major symptoms of left-sided heart failure are fatigue, dyspnea (orthopnea, paroxysmal nocturnal dyspnea), and the sputum production (sometimes bloody) that comes from pulmonary congestion Right-sided failure occurs when there is resistance to the flow of blood from the right heart structures (right atrium, right ventricle, pulmonary or lung artery) into the lungs or when the tricuspid valve, which separates the right atrium from the right ventricle, fails to work properly This results in a backup of fluid and pressure in the veins that empty into the right side of the heart Pressure then builds up in the liver and the veins in the legs The liver enlarges and may become painful; swelling of the ankles or legs occurs The major symptoms of right-sided heart failure are edema and nocturia (excessive urination at night caused by fluid redistribution while a person is lying down) The different types of edema possible are de- DIAGNOSIS A stethoscope can be used to detect rales, crackling noises that are caused by the movement of excess fluid in the lungs This can help locate where fluid has accumulated By listening to breathing sounds or thumping the chest, a physician can usually tell when fluid from the lungs has leaked (pleural effusion) into the chest cavity The fluid will also appear as a cloudy area on X-rays The stethoscope can also detect the sounds of the heart chambers filling and emptying and the heart valves opening and closing throughout the cardiac cycle Abnormal variations in these sounds can aid the physician in diagnosing and monitoring heart failure, because the condition is associated with one or two abnormal sounds in addition to the two sounds usually heard with the healthy heart Another symptom, blueness of the skin (called cyanosis) accompanied by coolness and moisture, most often in the fingers and toes, indicates low levels of oxygen in the blood (called hypoxia) Edema is detected by pressing the finger against the ankle or skin and noting how long it takes the depression to refill Liver enlargement is felt by examining the abdomen The neck vein may also be distended (See box, “Signs of Heart Failure During an Examination.”) A number of sophisticated diagnostic techniques may also be employed to diagnose and monitor heart failure and heart function The two main noninvasive HEART FAILURE Signs of Heart Failure During an Examination In the heart ● Heart enlargement ● Increased heart rate (tachycardia) In the lungs ● ● Crackling noises (rales) heard through a stethoscope indicating a buildup of fluid in the lungs Leakage of fluid from the lungs (pleural effusion) into the chest cavity In other areas ● Swelling (edema) of the skin and soft tissues, usually noted in the feet and ankles ● Edema of the lower back (sacral edema) ● Buildup of fluid of the abdominal cavity (ascites) ● increased size of liver (hepatomegaly) ● Ascites techniques for this purpose are the echocardiogram and the radionuclide angiocardiogram (See Chapter 10.) Both tests can quantify the level of heart dysfunction and distinguish between generalized as opposed to regional dysfunction In cardiac catheterization, a thin tube is introduced through a vein or artery into the heart The procedure determines whether there are blockages in the blood vessels and measures pressures in various chambers of the heart (See Chapter 10.) The electrocardiogram (ECG) provides a graphic record of the heart’s electrical impulses; it can detect increased wall thickness (called hypertrophy), heart enlargement, or various rhythm changes in heart failure The ECG may also be used to monitor the effects of drug treatments on the heart Chest X-rays can also detect an enlarged heart CAUSES An array of different problems can cause congestive heart failure (See box, “Causes of Congestive Heart Failure.”) Among them is coronary (ischemic) heart disease resulting from insufficient blood flow to the myocardium, or heart muscle This is usually caused by atherosclerosis, the buildup of fatty substances or plaque on the walls of the arteries that carry blood to the heart muscle The heart’s ability to perform decreases because ischemia results in the delivery of less oxygen and fewer nutrients to the heart muscle A heart attack may also cause congestive failure During a heart attack, the heart muscle is deprived of oxygen, resulting in tissue death and scarring The development of heart failure depends on the extent and location of scarring (See Chapter 15.) Long-standing high blood pressure is another common cause of heart failure Because there is greater resistance against which the heart must pump, the heart muscle works harder This results in an enlargement of the heart muscle, especially of the left ventricle, the heart’s main pumping chamber Eventually, this enlarged muscle tissue weakens, setting the stage for heart failure, especially if the pumping ability of the enlarged chamber greatly decreases Arrhythmias (irregular heartbeats) can lead to heart failure, but they usually have to be severe and prolonged, with a rapid rate of more than 140 beats per minute, and must often occur in the presence of an already weakened heart They change the pattern of filling and pumping of blood from the heart This condition may also lower output of blood to the point of heart failure (See Chapter 16.) Diseased heart valves are another cause of heart failure, which results when a narrowed or leaking valve fails to direct blood flow properly through the heart The problem may be congenital (inborn) or due to an infection such as endocarditis or rheumatic fever This increases the heart’s workload, thereby in- Causes of Congestive Heart Failure (CHF) ● Coronary (ischemic) heart disease resulting from insufficient blood flow to the heart muscle (myocardium) ● A heart attack, resulting in acute damage and then scarring of heart muscle tissue ● Chronic high blood pressure ● Major cardiac arrhythmia ● Diseased heart valve(s) ● Diseased heart muscle ● Congenital heart disease MAJOR CARDIOVASCULAR DISORDERS creasing risk of developing heart failure (See Chapter 13.) Cardiomyopathy, a disease of the heart muscle itself, can also lead to heart failure Causes of cardiomyopathy include infection, alcohol abuse, and cocaine abuse When heart failure seems to have no known causes, it is known as idiopathic heart failure (See Chapter 15.) HOW THE BODY TRIES TO PROTECT ITSELF When one system of the body is not functioning optimally, other systems may attempt to take over to make up for the problem In the case of heart failure, several types of compensation are possible First, the heart chambers may enlarge, and the heart may beat more forcefully to pump out more blood for the body’s needs In time, the overworked heart muscle enlarges (much as skeletal muscles grow larger during weight muscle training), creating increased muscle fibers with which the heart can pump more forcefully Second, the heart may be stimulated to pump more often, thereby increasing its output Third, a compensation mechanism called the renin-angiotensin system maybe initiated When the lack of blood volume coming from the heart (cardiac output) results in a decrease in the amount passing through the kidneys, the kidneys respond by stimulating the system to secrete hormones that prompt the kidneys to retain salt and water, and thereby increase blood volume This is an attempt to compensate for the decrease in output of the heart This leads to a rise in blood pressure as the body attempts to circulate the extra fluid volume and also ensures that adequate oxygen reaches the brain, kidneys, and other vital organs These compensation mechanisms keep the failing heart functioning almost normally in the early stages of heart failure As the disease progresses, however, compensation mechanisms cannot maintain proper circulation It may take years for a heart to go through the stages of enlarging, working harder, and finally breaking down In many cases, as when a person has hypertension, heart failure is preventable if blood pressure is treated adequately TREATMENT Whenever possible, the best treatment of congestive heart failure is one of prevention This includes diagnosing and treating high blood pressure and attempting to prevent atherosclerosis Other important preventive steps include not smoking, using alcohol in moderation if at all, and abstaining from cocaine and other illicit drugs A prudent diet, regular exercise, and weight control are also important When a patient is diagnosed as having heart failure, the first treatment is often restriction of dietary sodium Drugs may be prescribed as well Diuretics, available since the 1950s, are often used to help the kidneys get rid of excess water and sodium, thereby reducing blood volume and the heart’s workload (See Chapter 23.) Digitalis, a drug that has been used since the 18th century, is still a component of modern therapy It is prescribed to strengthen the heart’s pumping action Patients taking both diuretics and digitalis may need to supplement their levels of potassium Newer drugs for the treatment of heart failure include vasodilators, which cause the peripheral arteries to dilate, or open up This reduces the work of the heart by making it easier for blood to flow Among the newest vasodilators used for heart failure are the angiotensin-converting enzyme (ACE) inhibitors, which may be used, along with diuretics, in patients with mild-to-moderate or severe congestive failure ACE inhibitors, which include captopril (Capoten) and enalapril (Vasotec), block the production of a substance called angiotensin II, a potent constrictor of blood vessels If blood vessels are dilated, the amount of work needed for the heart to pump blood forward is decreased Other drugs used in the treatment of heart failure include calcium-channel blockers, which dilate blood vessels; beta blockers, which slow the heart (used only in unusual circumstances); and medications that affect various heartbeat irregularities Most cases, however, respond to diuretics and digitalis, especially when ACE inhibitors are added Sometimes, surgery proves effective When heart failure is due to valvular disease, surgical implantation of an artificial heart valve or valve repair may alleviate the problem Surgery may also be helpful in correcting congenital heart defects that can lead to heart failure Coronary artery bypass graft surgery and catheterization using a balloon to flatten fatty HEART FAILURE deposits (called angioplasty) are among the therapeutic techniques used to prevent and treat heart failure caused by occluded, or blocked, arteries Heart transplants are a last resort in treating severe heart failure caused by diseased heart muscle Although the success rate of heart transplants has significantly improved, the cost of the operation and the shortage of donor organs makes it impractical except as a last resort PROGNOSIS The outlook for most people with heart failure is dependent upon the cause of the heart failure and the overall degree of cardiac dysfunction An estimated 50 percent survive more than five years after diag- nosis That figure, however, is an average of all patients with varying levels of severity of the disease The prognosis for a specific person with heart failure depends to a large degree on effects of the disease, such as the level of blood output of the left ventricle, or his or her ability to exercise, as well as other factors, including age, overall health, and other medical conditions The sooner heart failure is diagnosed and action is taken to control the problem, the better In many cases, heart failure can be effectively treated to prevent or slow the progression of the disease and to alleviate its symptoms Therapy can achieve several goals: It can improve the performance of the left ventricle, prevent further deterioration of heart function, improve a patient’s ability to exercise, and improve quality of life In addition, it is possible that in selected instances, early, effective treatment may increase a person’s likelihood of improved survival 183 CHAPTER 15 HEART MUSCLE DISEASE FORRESTER A LEE, M D Compared with other cardiovascular diseases, heart muscle disease (cardiomyopathy) is relatively rare In its most common form, the disease accounts for only 50,000 new cases in the United States each year, while the annual number of stroke cases, for example, reaches 500,000 Unlike many other cardiovascular disorders that tend to affect the elderly, cardiomyopathy commonly occurs in the young and can have a tragically brief course Cardiomyopathy (cardio meaning heart, myopathy meaning muscle disease) refers to a group of disorders that directly damage the muscle of the heart walls In these disorders, all chambers of the heart are affected The heart’s function as a pump is disrupted, leading to an inadequate blood flow to organs and tissues of the body Depending on the nature of the injury or abnormality in the heart muscle and the resulting structural changes in the heart chambers, one of three types of nonischemic (not caused by heart attack) heart muscle disease may be present dilated congestive, hypertrophic, or restrictive (See Table 15.1.) Massive or multiple heart attacks may also lead to severe heart damage as a result of a disruption of blood supply to heart muscle The damage can result in functional impairment and structural abnormalities similar to those found in the other types of cardiomyopathy This type of heart disease, resulting from coronary artery disease, is called ischemic car- diomyopathy When used alone, however, the term “cardiomyopathy” refers to heart muscle disease that is not caused by heart attacks DILATED CONGESTIVE CARDIOMYOPATHY This is the most common type of heart muscle disease It is generally called either dilated or congestive cardiomyopathy This type of disease damages the fibers of the heart muscle, weakening the walls of the heart’s chambers Usually, all chambers are affected, and depending on the severity of the injury, they lose some of their capacity to contract forcefully and pump blood through the circulatory system To compensate for the muscle injury, the heart chambers enlarge or dilate The dilation is often more pronounced in the left ventricle, the heart’s main pumping chamber (See Figure 15.1.) Dilated cardiomyopathy causes heart failure—an inability of the heart to provide an adequate supply of blood to the body’s organs and tissues—which, if left untreated, is always associated with excess fluid retention, congestion in the lungs and liver, and swelling of the legs Fluid retention occurs during heart failure because many organs fail to receive suf185 MAJOR CARDIOVASCULAR DISORDERS Table 15.1 Types of Heart Muscle Disease (Cardiomyopathy) Type Therapy Dilated congestive: Cavity of the heart is enlarged and stretched Cause is usually unknown When underlying cause is unknown, treatment focuses on relieving symptoms and improving function Drugs used include digitalis and digoxin (Lanoxin and others), diuretics such as furosemide (Lasix and others), steroids to relieve inflammation, and ACE inhibitors such as captopril (Capoten) When symptoms cannot be relieved, heart transplant may be considered Limit stressful physical activity, and use medication, including beta blockers or a calcium channel blocker such as verapamil (Calan, Isopton, Verelan) If medication does not relieve symptoms, undergo surgical removal of excess muscle tissue that obstructs blood flow in the heart chambers If surgery does not help, heart transplant may be considered Treated with medications that alleviate symptoms (see dilated congestive section above) No cure exists Hypertrophic: Muscle mass increases, causing chest pain, palpitations, and possibly fainting during physical activity May be genetically acquired Restrictive: Abnormal cells, proteins, or scar tissue infiltrate the heart, causing the chambers to become thick and bulky Most common cause in the United States is a disease (amyloidosis) that is associated with cancers of the blood Type Ischemic (related to coronary artery disease): Therapy Treated with medications that relieve symptoms of heart failure and coronary artery disease (see above) Angioplasty and coronary artery bypass grafting may help increase blood flow to the heart, enhancing heart muscle function When neither drug therapy nor surgery helps, heart transplant may be considered ficient blood flow The kidneys respond to this lack of blood supply by retaining more than the usual amount of salt and water With time, excess fluid retention leads to congestion in the lungs and other organs At the end of the day, much of the retained fluid gravitates to the lower portions of the body and causes swelling in the legs (See Chapter 14 for more information on heart failure and its symptoms.) THE COURSE OF DILATED CARDIOMYOPATHY When the chambers dilate, the muscle fibers in the heart walls stretch, enabling them to contract more forcefully (This is characteristic of all muscles.) Growth of muscle tissue, which can to some extent rebuild damaged areas of the heart wall, also helps to keep up normal function If the injury to the heart muscle is relatively mild, new muscle growth and the process of fiber stretching, which occurs roughly in proportion to the muscle damage, can partially restore cardiac function If, however, injury is severe, the heat's function deteriorates When damage to the heart is chronic or recurrent, as may occur with a prolonged exposure to excessive amounts of alcohol or infection, chamber dilation maybe slow and progressive Eventually, the enlarged, thin-walled ventricles become flabby and cannot generate sufficient pressure to pump blood effectively throughout the body Dilated cardiomyopathy typically leads to a steady deterioration in heart function, although the course HEART MUSCLE DISEASE a sedentary life, may experience few symptoms and be unaware that the heart is failing With advanced disease, symptoms may occur with minimal activity or even in the absence of physical exertion In more than 80 percent of cases, the cause of dilated cardiomyopathy is unknown Major causes of the disease are inflammation of the heart muscle (myocarditis), excessive alcohol use, poor nutrition, and, rarely, complications arising shortly before or after childbirth (peripartum) and genetic disorders (See box, “Causes of Dilated Congestive Cardiomyopathy.”) HEART MUSCLE INFLAMMATION (MYOCARDITIS) Figure 15.1 In dilated cardiomyopathy, the cavity of the heart is enlarged and stretched of the decline varies greatly and is difficult to predict for any given patient Most patients go through periods of relatively stable heart function that may last several months or even years, However, the majority eventually succumb to complications of the disease Most commonly, they die of progressive heart failure that is not amenable to treatment, although some die suddenly and unexpectedly Most instances of sudden death are believed to result from ventricular fibrillation-an abnormally fast and irregular heart rhythm with ineffective contractions that causes death within minutes Patients with dilated cardiomyopathy are at risk of sudden death because the underlying disease process disrupts the normal electrical pathways of the heart, possibly causing rhythm disturbances Less often, sudden death may result from an embolus-a blood clot that dislodges from one of the heart chambers, travels to another vital organ, such as the brain or lungs, and obstructs the blood supply Poor circulation and stagnation of blood in the dilated heart chambers provide favorable conditions for blood clot formation Most cases of dilated cardiomyopathy probably result from inflammation of the heart muscle (myocarditis), but not all cases of heart muscle inflammation lead to dilated cardiomyopathy In fact, myocarditis is often categorized as heart muscle disease in its own right In Western Europe and the United States, myocarditis occurs most often as a complication of a viral disease, but it is a rather rare complication Viral infections are believed to cause indirect damage to the heart The invading virus provokes proteins that normally are confined within heart muscle cells to become exposed to the bloodstream This sets off an inflammatory process as the body mistakenly assumes these newly exposed proteins belong to foreign cells and attacks them in the same way it fights viruses and bacteria The unfortunate result is inflammation and injury to the body’s own tissues—in the case of myocarditis, the tissues of the heart Many organisms can infect and injure the heart muscle Coxsackie Type B, a virus among those that Causes of Dilated Congestive Cardiomyopathy In many cases, the cause cannot be identified When causes are known, they include: ● SYMPTOMS AND CAUSES OF DILATED CARDIOMYOPATHY The main symptoms of dilated cardiomyopathy are those of congestive heart failure—breathlessness or fatigue during physical activity and swelling of the lower legs Some patients, especially those who lead Inflammation of the heart muscle (myocarditis), either infectious or noninfectious ● Excessive alcohol consumption ● Nutritional deficiencies ● Complications arising shortly before or after childbirth (peripartum) ● Genetic disorders 187 INDEX clonidinelchlorthalidone (Combipres), 303 “clubbing,” 249 coarctation of the aorta, 17, 248, 250, 255–256 surgery for, 327, 328, 329 cocaine, 18, 32, 82, 177, 199, 220, 223 coffee, see caffeine Cohen, Lawrence S., 11–20, 107–114, 283-304 collagen vascular disease, 19 collateral circulation, 144 colon cancer, 45, 52 communication, with stroke survivors, 229–231 community phase, 357 computed tomography (CT scan), 126, 156, 194, 213 stroke and, 224, 225 conduction system, congenital heart defects, 11, 17, 375–376 in children, 247–258 coarctation of the aorta, 17, 248, 250, 255–256, 327, 328, 329 cyanotic, see cyanotic conditions development of heart and, 247–248 diagnosis of, 118, 119, 249252 in fetus, 248–249 incidence of, 17, 247 patent ductus arteriosus (PDA), 17,252-253,327, 328–329 pulmonary stenosis, 16, 17, 174, 248, 255, 311 surgery for, 324–329 valvular, 15, 17, 326, 328 see also aortic stenosis; septal defects congestive heart failure (CHF), 341, 376–377 use of term, 177 see also heart failure consciousness, loss of, 18, 144 see also fainting consumers, patients as, 359–362 contrast venography, 208 cookbooks, recommended, 67 cooking, 66–67 coronary angiography, see angiography coronary arteries, 5, 7, 134, 143 blood clot in, 157–158 catheterization of, see coronary arteriography narrowing of, see angina pectoris; atherosclerosis nicotine and, 73 X-rays of, see angiography coronary arteriography, 127,268 coronary artery bypass surgery, 12, 52, 73, 142, 146, 147, 316–318 coronary artery bypass surgery (cont.) angioplasty compared with, 306 heart failure and, 182–183 coronary artery disease (CAD), 133–143, 177, 341, 377378 complications of, 378 defined, 12 diagnosis of, 136–139, 378 life-style modification and, 142–143 stroke and, 218 symptoms of, 133, 135–136, 378; see also angina pectoris treatment of, 139–143, 301, 305–311, 378 see also arteriosclerosis; atherosclerosis; coronary heart disease; myocardial ischemia coronary artery spasm, 241 coronary care units (CCUs), 144, 146-148 Coronary Drug Project, 43 coronary heart disease (CHD), 27–32, 37, 40,42, 181, 238-242, 341, 377–378 arrhythmia and, 17 in elderly, 265–266 exercise and, 85, 88, 93 gender and, 28, 238–243 racial differences and, 274– 275 stroke and, 215, 217, 218, 222 use of term, 12 see dso arteriosclerosis; atherosclerosis; coronary artery disease; myocardial ischemia coronary thrombosis, 157–158 coronary veins, cor pulmonale, 72, 377 cortisone, 19, 156, 188, 190, 260 costs, health, 360, 361–362 cotinine, 77 Coxsackie virus Type B, 110, 187–188 CPR, see cardiopulmonary resuscitation crack, 82 see also cocaine cyanotic conditions, 17, 113, 180, 250, 251, 256–258, 374– 375 central vs peripheral, 113 hypoplastic left heart syndrome, 258, 327, 328 persistent truncus arteriosus, 257 pulmonary atresia, 257-258 tetralogy of Fallot, 17, 256, 325, 326,327 total anomalous pulmonary venous connectiorl, 258 cyanotic conditions (cont.) transposition of the great arteries, 17, 256–257, 326, 328 tricuspid atresia, 257, 327, 328 cyclosporine (Sandimmune), 323–324 D dairy products, 53, 59, 61, 67 daunorubicin (Cerubidine), 193 death, 43, 133–134 arrhythmia and, 195 from atherosclerosis, 23 cardiomyopathy and, 187, 191, 192–193 from coronary artery disease, 133, 134, 139 from coronary heart disease, 12,28,41, 177 from heart attacks, 12, 116, 133, 134, 143, 148, 149, 242, 274 from heart failure, 15 high blood pressure and, 29 of spouse, 98 from strokes, 14–15, 148, 215, 274 sudden (cardiac arrest), 93, 191, 192–193, 224, 372–373 Deckelbaum, Lawrence, 133– 148, 283–304 defibrillator (automatic implantable cardioverter defibrillators), 145, 146, 204, 268, 335–338 implantation of, 337–338, 337 workings of, 336-337 demand pacemakers, 332 De Mortu Cordis (Harvey), 313 dental work, antibiotics and, 16, 19, 169, 170, 171, 244, 252 depression, 165, 232 drug selection and, 284 fatigue and, 113, 114 diabetes, 29, 30, 31, 37, 114, 293 adult-onset (Type II), 31, 52, 270 congenital heart disease and, 248 diet and, 54, 55 drug selection and, 285 exercise and, 93 hypertension and, 157, 161– 162 juvenile-onset (Type I), 31 peripheral vascular disease and, 13, 210, 211 race and, 29, 276 stroke and, 31, 217, 218, 223 symptoms of, 156 in women, 241 diagnosis, 105–129 symptoms and, 107–1 14 see also tests; specific diseases diastole, diastolic blood pressure, 29, 120, 151, 152, 153 421 INDEX diet, 51–70, 143 cholesterol and, 40–42, 45–49, 51, 52, 57, 59, 61, 62, 64, 259, 260, 295 components of, 53-56 ethnicity and, 277 fad and crash, 162, 163 foods to emphasize in, 59, 61 high-carbohydrate, 56, 58–59 high-protein, 55 implementation of, 57–62 low-fat, 30,33, 45–48, 51, 56, 58–59, 260, 295 low-sodium, 15, 160, 162, 258 “magic bullets” and, 53 practical tips for, 64-70 race and, 276, 278 sample menus and, 60, 69–70 serving and portion size recommendations for, 58–59 smart substitutions and, 62 vegetarian, 55 weight-loss, 63–64 Yale recommendations for, 56–57 see also foods; specific foods and food groups digitalis, 16, 18, 173, 182, 190, 202, 286, 289, 298–299 digitoxin (Crystodigim Purodigin), 299 digoxin (Lanoxicaps; Lanoxin), 190,202,253,257,289, 290,296, 298–299 dilated congestive cardiomyopathy, 185–191, 187 course of, 186–187 diagnosis of, 190 myocarditis and, 187-188 prognosis for, 191 symptoms and causes of, 187– 190 treatment of, 190–191 diltiazem (Cardizem), 202, 284, 294 diphtheria, 188 dipyridamole (Persantine), 138, 268, 292, 315 Directory of Medical Specialists, 360,362 disopyramide phosphate (Nor~ace), 202-203, 289 dissecting aneu”~sm, 13, 110, 212,212 iuret ‘ ~: 9~:& 253? 257