Articles on Medical Diseases and Conditions

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  • Tricuspid Valve Problems

    The tricuspid valve is on the right side of the heart, regulating the blood ?ow between the right atrium and the right ventricle. Disease in this valve is fairly rare. However, regurgitation (backward leakage of blood through the valve) may occur as the only valve problem or may occur with other problems. Stenosis (narrowing of the valve opening) is most often congenital (from birth) and rarely occurs in adults.

    Tricuspid Regurgitation

    If the tricuspid valve fails to close fully, blood leaks back (regurgitates) from the right ventricle into the right atrium. Instead of the blood mov- ing forward through the right ventricle to the lungs to pick up oxygen, it backs into the major veins. It most often occurs if the right ventricle becomes enlarged or stiffened from another disorder, such as high blood pressure within the lungs and right side of the heart (pulmonary hypertension). Tricuspid regurgitation may also result from infective endocarditis , rheumatic fever , or car- diomyopathy .
    A person with tricuspid regurgitation usually does not have any symptoms, or the symptoms may be mild enough to live with for years, and no treatment is necessary. If you have high blood pressure in the lungs, as well as tricuspid regurgitation, you may develop symptoms of heart failure such as swelling in the stomach, liver, feet, and ankles; weakness and fatigue; and decreased urine output. Treatment with med- ications such as diuretics may relieve the symptoms. If tricuspid regur- gitation is due to pulmonary hypertension, calcium channel blockers may be prescribed. In some people, surgery to replace the tricuspid valve  may be necessary.
    If you have tricuspid regurgitation because of an abnormal valve, you are at increased risk of infective endocarditis, and you will need to take antibiotics before some dental and surgical procedures.

    Tricuspid Stenosis

    If the tricuspid valve is narrowed or blocked, blood ?ow from the right atrium to the right ventricle slows down. The atrium may become enlarged and the blood ?ow to the right ventricle may be impaired. Tricuspid stenosis, which is rare, may be congenital (from birth) or the result of rheumatic fever. If rheumatic fever is the cause, other valves of the heart are usually involved.
    Generally, the only symptoms of tricuspid stenosis are fatigue and the pain pressure in the liver (which you are likely to feel in your upper right abdomen). Often these symptoms, as well as some shortness of breath and ?uid retention, are caused by disease in another valve. Treat- ment is likely to focus on the other valves. If your tricuspid valve is severely damaged, surgery is possible. As with other valve disorders, you are at increased risk of infective endocarditis, and your doctor may advise you to take antibiotics before some dental and surgical procedures.

  • Mitral Valve Problems

    The mitral valve regulates the ?ow of blood from the left atrium to the left ventricle, the main pumping chamber that pumps blood out into the arteries. It is composed of two lea?ets supported by a ?ne structure of stringlike tissues attached to the heart muscles. The mitral valve may be affected by prolapse, regurgitation, or stenosis.

    Mitral Valve Prolapse

    About 2 percent of the U.S. population have mitral valve prolapse, meaning that one or both of the ?aps of the mitral valve are enlarged and the supporting muscles are too long. As a result, the lea?ets do not close tightly and they billow into the atrium as the left ventricle con- tracts. Sometimes a small amount of blood leaks back into the atrium (regurgitation). Although there may be a variety of causes, many forms of prolapse are probably inherited. It occurs more frequently in women than men, often in very slender people who may have minor chest wall irregularities or scoliosis (a curvature of the spine). But it may be more severe in men.
    In the vast majority of people, mitral valve prolapse is completely harmless and does not cause any long-term problems. Some people experience symptoms and seek treatment for them; symptoms include chest pain, palpitations (the sensation of feeling the heart beat), an irregular heartbeat, fatigue, shortness of breath when lying down, trou- ble breathing after exercise, or coughing.
    Your doctor may detect mitral valve prolapse when listening to your heart through a stethoscope, because the billowing lea?ets can cause a characteristic click, followed by a murmur. If necessary, he or she can con?rm the diagnosis with an echocardiogram and assess the degree of regurgitation.
    If you have little or no regurgitation and an otherwise normal heart, you will not need treatment. But if signi?cant regurgitation develops, or if other illness is present, you may be at risk of a serious problem, infec- tion of the valve.
    Symptoms of mitral valve prolapse may improve with regular exer- cise, a decrease in caffeine consumption, and adequate ?uids. Or you may be prescribed beta-blockers to alleviate symptoms such as palpitations.

    Mitral Valve Regurgitation

    A mitral valve that fails to close completely when the powerful left ventricle contracts allows blood to “regurgitate” back into the atrium, undermining the one-way flow. Mitral valve regurgitation may be caused by damage to the valve from rheumatic fever , infective endocarditis , or a heart attack that damages the part of the muscle attached to the valve. The regurgitation can also result from enlargement of the left ventricle, possibly brought on by coronary artery disease or untreated high blood pressure, which stretches the perimeter of the mitral valve so that the lea?ets do not close completely.
    Many people have no symptoms; in others, symptoms develop over a period of years because the heart compensates for the problem. But over time, the extra effort can cause the left ventricle to enlarge or pres- sure to build up in the lungs as the blood leaks backward. The symp- toms of regurgitation may come on slowly and can include shortness of breath or rapid breathing, fatigue, heart palpitations, or cough.
    To relieve the symptoms of mitral valve regurgitation, your doctor may prescribe medications to lower your blood pressure or diuretics to rid your body of excess ?uids. He or she may also recom- mend that you take antibiotics before some dental or surgical proce- dures to prevent infection of the valve.
    If surgery is necessary to restore valve function, your doctor will time the surgery carefully to be sure that your heart muscle does not become too weak to withstand the operation. The surgeon will repair your valve if possible, but in some people, an arti?cial valve is the best solution . After surgery, the long-term outlook for most people is very good.

    Mitral Valve Stenosis

    Mitral valve stenosis is a narrowing of the mitral valve. The narrowing or obstruction causes an increase in the pressure behind the valve in the left atrium. In most people, this type of damage to the valve was caused by a case of rheumatic fever in childhood . Because the use of antibiotics has dramatically decreased the occurrence of rheu- matic fever, mitral valve stenosis is becoming rare in the United States. It may occasionally occur in older people as a result of calcium deposits on the perimeter of the mitral valve, combined with the degenerative aging process that affects the tissues of the heart.
    Many people with mild mitral valve stenosis do not experience symptoms, and treatment is not required. If the condition does cause symptoms to develop, they may develop slowly. Symptoms may include trouble breathing at night or after exercise; coughing, perhaps with traces of blood; fatigue; or chest pain that gets worse with exertion. There is risk of abnormal heart rhythms in the left atrium (atrial ?bril- lation), which can cause blood clots to form in the heart. The clots can dislodge and travel to the brain, increasing your risk of stroke.
    A person with mitral valve stenosis may need to take antibiotics before undergoing certain medical or dental procedures to prevent infective endocarditis (see page 192) in the valve. Medication to slow the heart rate may help some people feel better. In some people with moderate stenosis, a balloon valvuloplasty (a procedure to open the valve with a balloon; ) may be an option. For a person with a severely diseased valve, particularly an older person, surgical repair or replacement of the valve may be necessary.

    Aortic Valve Disease

    The aortic valve, which has three crescent-shaped cusps (lea?ets), regu- lates blood ?ow from the left ventricle into the aorta, where it then cir- culates to the rest of the body . Either stenosis (narrowing) or regurgitation (backward leakage) can disrupt the blood ?ow. The valve can be damaged by rheumatic fever or infection. But some people are born with a bicuspid aortic valve—a valve with two lea?ets instead of three. A bicuspid valve may be less ef?cient and more prone to infection or calci?cation with aging. The aorta may be abnormal, too, in people with bicuspid aortic valves, regardless of the severity of the valve disease.

    Aortic Valve Regurgitation

    When an aortic valve does not close completely, blood leaks or regur- gitates back into the left ventricle. The condition occurs more com- monly in men, often between the ages of 30 and 60. The most typical causes of mild regurgitation are structural abnormalities of the valve (such as a bicuspid valve), damage from rheumatic fever, high blood

    pressure, or calci?cation on the valve as a result of aging. In the most serious cases, the valve may suddenly start leaking as a result of infective endocarditis that actually makes holes in the lea?ets or from a tear or severing of the aorta above the valve.
    As with other heart valve problems, a person may not experience symptoms for years. But if the regurgitation forces the left ventricle to work harder over a long period, it may enlarge. Left untreated, irreparable damage to the left ventricle—the heart’s main pumping chamber—could take place.
    Symptoms, if or when they occur, include shortness of breath, chest pain with exercise, swelling in the ankles, fatigue, and a rapid pulse. Even if you do not have symptoms, your doctor may detect aortic regurgitation by listening to your heart sounds through a stethoscope. He or she will con?rm the diagnosis and assess your heart function with tests, including a chest X-ray, echocardiogram , and elec- trocardiogram . You may be advised to take antibiotics before some dental and surgical procedures to prevent endocarditis. Medications to treat high blood pressure and reduce the heart’s workload may help reduce symptoms. Your doctor will evaluate you periodically by monitoring changes in your symptoms, your phys- ical examinations, and tests such as echocardiograms.
    Your doctor may recommend surgery to replace the aortic valve (see page 206) and limit damage to the heart muscle. As with surgery for mitral regurgitation, the procedure will be carefully timed to correct the problem before the heart is substantially weakened. If the problem is corrected before damage occurs, you are very likely to be able to return to a normal lifestyle.

    Aortic Stenosis

    If your aortic valve (which regulates the blood ?ow between your left ventricle into the aorta) becomes narrowed, your heart must work harder to force blood through the valve. As a result, the left ventricle enlarges and thickens. Over time, the heart may be unable to maintain the workload, and ?uid may back up in the lungs.
    Today the most common cause of aortic stenosis is a degeneration of the valve that occurs with aging. Calcium, a mineral found in the blood, can build up on the valve over the course of your lifetime. Some calci?- cation may not cause any trouble, but in some people, calcium deposits and scarring develop that deform or even fuse the valve leaflets so that they do not close tightly. Another frequent cause, particularly in people diag- nosed before the age of 50, is a congenital (from birth) defect in a valve, for example, the bicuspid valve, which may calcify it. Very high levels of LDL (low density lipoprotein) cholesterol also promote increased calci?cation (forming of calcium deposits) around the heart valve. Aortic stenosis is more common in men.

    If the stenosis is severe, replacement of the valve (see page 206) may be required. After surgery, most people are able to resume a normal lifestyle. Balloon valvuloplasty (inserting a balloon-tipped catheter; see page 204) of the aortic artery is a temporary solu-

    tion in adults if they are not able to have surgery when the stenosis is diagnosed. In some young adults or children, valvuloplasty will open the valve.

  • How Valve Problems Occur

    Any of the four heart valves (mitral, aortic, tricuspid, or pulmonary) can be defective or become diseased in a variety of ways. The most common problems occur in the mitral and aortic valves, on the left side of the heart. The most typical causes of valve problems are:
    • Congenital defects, meaning that a person is born with an abnor- mal heart valve
    • Infectious disease, usually bacterial endocarditis, which can dam- age the valve with scar tissue
    • Rheumatic fever, now uncommon
    • Changes in valve structure or function that occur with aging
    • Coronary artery disease, a heart attack, or heart muscle dysfunc- tion that leads to problems with the way valves work, because of structural changes in the heart or a decrease in blood ?ow to the muscle that controls the valve’s functioning.
    The symptoms of valve problems can be subtle and gradual. They differ depending on which valve is involved and what type of malfunction is occurring. (For detailed information about speci?c valve disorders.)

    Congenital Valve Defects

    Some people are born with a defective valve but may never experience symptoms or may not have problems until later in life. Then the abnor- mal valve may be more vulnerable to calcium deposits that occur as a result of aging or abnormal functioning. If the defect is severe, the symptoms may occur earlier in life.
    A valve defect that is congenital (present since birth) also increases a person’s risk of endocarditis, an infection of the lining of the heart (endocardium) or heart valves. Small amounts of bacte- ria may enter your bloodstream but are usually removed by your body’s defense system. However, these bacteria are somewhat more likely to lodge on an abnormal valve, where they can cause an infection that can damage your heart valve. For this reason, if your doctor determines that you have a defective heart valve, to prevent infection you may need antibiotics to kill the bacteria before you have certain dental or surgical procedures.

    Infective Endocarditis

    Infective endocarditis is an infection of the lining of the heart chambers (endocardium) or the heart valves. It is caused by microorganisms— usually bacteria, but sometimes fungi or other types of microorganisms— that enter your bloodstream and lodge in your heart. These microorgan- isms occur naturally and harmlessly in other parts of your body, such as your mouth or urinary tract, and may enter your bloodstream from any tiny cut or breakdown of tissue (see box, page 194). The presence of bacteria in your bloodstream (which is called bacteremia) does not nec- essarily lead to infection, and not all bacteria are even capable of causing endocarditis. It is a relatively uncommon disease.
    When endocarditis does occur, the microorganisms in the bloodstream stick to the surface lining of the heart or abnormal valves, per- haps aided by microscopic blood clots that have formed at the site. Your body responds by sending in immune cells and ?brin (a clotting material) to trap the organism. A clump of cellular material, called a vegetation, forms over the organism. Vegetations can interfere with a valve’s function, or they can break off and block a
    blood vessel in a vital organ.
    You are more likely to get endocarditis if you have existing valve disease, if you have had heart valve surgery, if you have a congenital heart defect, if you had rheumatic fever as a child that scarred your heart valves, or if you have an arti?cial heart valve or other foreign material in your body. Drug addicts who share needles or use dirty needles are also at risk for endocarditis.
    Symptoms of endocarditis are variable, but they usually include fever. Many people report other ?ulike symptoms, too, such as muscle aches and pains, fatigue,
    night sweats, and loss of appetite. If you have chronic endocarditis, also known as subacute endocarditis, the symptoms can be subtle and last for months before the diagnosis is made. Sometimes symptoms of heart failure such as shortness of breath and confusion are the ?rst sign of a problem. You or your doctor may also notice changes in your skin and nails, such as red spots on the palms of your hands or the soles of your feet, painful sores on the tips of your ?ngers and toes, or dark lines (tiny hemor- rhages) under your nails that resemble wood splinters. Endocarditis can cause additional problems such as anemia and blood in the urine.
    Your doctor may initially suspect endocarditis by your symptoms, especially if you are at known risk because of congenital heart disease, rheumatic fever, or valve disease. He or she will listen to your heart sounds with a stethoscope and may report a new heart murmur (the sound of turbulence in the blood ?ow through your heart) or a change in an old one. From blood samples that are sent for cultures, your doc- tor can identify if there is an infection and which microorganism is caus- ing the infection. Only rarely are blood cultures negative (that is, falsely suggesting no problem) in people with endocarditis. An echocardiogram will often con?rm the diagnosis by showing vegetations on the heart valve. The echocardiogram will also show the size of your heart and indicate how well the valves and heart wall are functioning.
    To treat endocarditis, you will need to take intensive doses of antibiotics for 2 to 6 weeks to kill the infecting microorganisms in your bloodstream and to sterilize the heart valve. At ?rst, you will need to be hospitalized so that the antibiotics can be given intravenously. In some people who respond well to the initial treatment, the full course of antibiotics may be completed at home or in a long-term-care facility. Your doctor will want to do regular blood tests to ensure that the med- ication is working.
    In some people, endocarditis seriously damages a heart valve (natural or arti?cial). Endocarditis can also cause heart failure, the infection can extend into the heart, or the vegetations can repeatedly break off and travel throughout the bloodstream. Surgery may be necessary to remove infected tissue and repair or replace the valve .

    Rheumatic Fever

    Rheumatic fever was once the most common cause of heart valve problems. This inflammatory disease, which can develop as a result of untreated strep throat in children more commonly than in adults, occurs in some people when the body’s immune response to ?ght the strep infection mistakenly attacks connective tissue (such as joints or the heart) instead. The affected tissue, often the heart valves, swells and develops scars. On a valve, the scar tissue may interfere with either opening or closing of the valve lea?ets.
    Fortunately, the use of penicillin and other antibiotics to treat strep throat has almost eradicated rheumatic fever in the United States. But rheumatic fever remains a concern throughout the world. Without antibiotic treatment, anyone who gets strep throat can develop rheu- matic fever, but it is most likely to occur in children from 5 to 15 years old. There is probably a genetic factor involved that makes some people more susceptible to rheumatic fever. The damage to heart tissue can last a lifetime, although it may not be noticeable for years after the illness.
    If you have had rheumatic fever, even decades ago, you are more sus- ceptible to heart attacks and valve disease. Although rheumatic fever rarely affects adults, you are more susceptible to it if you had it in child- hood. Be sure to tell your doctor if you know that you have a history of rheumatic fever; you may need to take preventive antibiotics.

    To protect yourself against the rare occurrence of rheumatic fever, it is important to get prompt treatment for a strep throat (caused by Streptococcus bacteria). Symptoms of strep throat include a sore, red throat; dif?culty swallowing; a sudden fever; swelling in the glands in the neck; and sometimes a rash. If you experience these symptoms for 3 days, see your doctor to be tested for a strep infection. With antibiotic treatment, the symptoms are likely to disappear within a few days. It is essential that you continue taking the antibiotics as long as your doctor instructs, even after the symptoms are gone, to reduce the risk of rheu- matic fever (though only a small percentage of strep infections result in rheumatic fever).
    Symptoms of rheumatic fever can occur in 3 days to 1 month or more after an untreated strep infection. The symptoms include fever; joint pain or swelling in your wrists, elbows, knees, or ankles; nodules under the skin on your elbows or knees; a raised rash on your chest, back, or stomach; or weakness or fatigue.
    See your doctor immediately if you experi- ence these symptoms. He or she will do a throat culture (take a swab of material from your throat for analysis) and may order a chest X-ray or electrocardiogram.
    If you have a strep infection that leads to rheumatic fever, your doctor will probably prescribe anti-inflammatory medications, including aspirin, to reduce swelling. You may also need to take a diuretic to get rid of excess fluids. Your doctor may prescribe antibiotic treatment monthly or even daily for life, to prevent reinfection.
    If your heart has been damaged by rheumatic fever, you may need to take specific antibiotics if you undergo certain dental or surgical procedures. Surgery to repair or replace a damaged valve may be necessary .

  • Heart Valve Problems

    The four valves that control the one-way ?ow of blood through the chambers of your heart open and close with your every heartbeat. These delicate structures deep inside your heart are critical to the meas- ured passage of about 100 gallons of blood every hour. Responding to pressure changes behind and ahead of them, the lea?ets (or cusps) of each valve must open fully and close tightly to keep blood moving
    properly.
    If the valves are malformed or not fully functioning, two types of problems can interfere with the one-way ?ow. If a valve fails to open fully, impeding the forward ?ow of blood, the condition is called steno- sis. Since the narrowed heart valve may limit blood ?ow, this can cause symptoms from inadequate circulation. Stenosis is usually the result of the lea?ets thickening, stiffening, or even fusing together. Over time, the heart has to work harder to push blood through the valve, which can damage the heart muscle and enlarge the heart chamber.
    If a valve cannot close completely to seal off back-?ow, the problem is called regurgitation (also known as insuf?ciency or incompetence). Because blood is leaking backward, the heart chamber behind the valve tends to enlarge and may pump less ef?ciently.
    Your heart has remarkable ability to adapt to and compensate for valve problems. Often a doctor can detect an abnormality in one of your valves by listening to your heart sounds through a stethoscope. The dis- ruption in ?ow causes some audible blood turbulence, called a heart murmur. Because the heart has adapted, you may not have any symptoms and your heart may function quite normally for decades. But if, over time, your heart can no longer compensate, then symptoms such as shortness of breath can develop. It is important to have the problem diag- nosed so it can be treated before permanent damage is done to heart muscle.

  • Minimally Invasive Heart Surgery

    Cardiologists in some medical centers are exploring two alternatives to coronary bypass surgery in efforts to ?nd less invasive and less expensive ways to treat coronary artery disease. Both of these alternatives are prom- ising, but the results and long-term outcome are still being evaluated.

    Port-Access Coronary Artery Bypass (PACAB or PortCAB)
    For this procedure, your heart is stopped and a heart-lung machine assumes its function. The surgeon makes small incisions, called ports, in your chest and may remove part of the rib over your heart. He or she performs bypass grafting through these ports, viewing the work on video monitors rather than directly.

    Minimally Invasive Coronary Artery Bypass (MIDCAB)

    This procedure is done without the heart-lung machine, while your heart is still beating. It is used only when one or two arteries are being bypassed. The surgeon creates the small ports described above, and also makes a small incision directly over the blocked artery, so that he or she can view the work area directly, instead of on a monitor. Usually, an artery from the chest wall is used for this procedure.

  • Coronary Artery Bypass

    Coronary artery bypass, which creates new routes for blood to ?ow around or bypass a clogged artery, is a major surgical procedure to restore adequate blood supply to the heart. To perform a bypass, a sur- geon removes part of a vein from the person’s leg or thigh, or an artery from the chest wall or arm, and grafts the segment to a blocked coro- nary artery to form a detour around the blockage. You may sometimes hear the operation called CABG (coronary artery bypass grafting, or “cabbage”) or CAB (coronary artery bypass). Doctors may recommend bypass surgery as an aggressive strategy to treat coronary artery disease for a variety of reasons: when medications and lifestyle changes are not enough to prevent severe angina or heart attack, when blockages are numerous and extensive, or when a medical condition such as diabetes or heart failure make other treatments such as angioplasty less work- able. (See “Considering Your Options,” ).
    In the United States, more than 500,000 people had bypass surgery in a recent year. Bypass surgery requires dividing the sternum (breastbone) in order to expose the heart. The operation usually  requires putting the person on a heart-lung machine throughout the procedure, meaning that the person’s heart is stopped and not moving while the surgeon works on it.
    A person may require more than one bypass to provide adequate blood to the heart. The number of arteries bypassed is not totally indicative of how severe your condition is, however. The location and extent of the blockages are signi?cant as well.

    What to Expect

    Most coronary artery bypass operations are sched- uled surgeries, rather than being done as an emer- gency measure. If your cardiologist recommends a coronary artery bypass, you will have the opportu- nity to discuss why he or she wants you to have the surgery, what the risks are, what your alternatives
    are, and what your family needs to know about your surgery and recov- ery period. If you decide to proceed with the surgery, be sure to remind your doctor about any medications you are taking, including over-the- counter drugs and supplements. Make a list of your medications and bring it with you to the hospital when the surgery is scheduled. As the day of the surgery approaches, tell your doctor about any changes in your health. It is especially important to be aware of symptoms of a cold or ?u, such as fever, chills, coughing, or a runny nose. Even minor infections could affect your recovery.
    You will probably be admitted to the hospital the morning of the sur- gery, or perhaps the night before. You will be asked to bathe before arriving. You will be asked not to eat or drink anything after midnight before the surgery, to prevent regurgitating the stomach contents and choking on them. (If you do have something to eat, be honest and tell the doctor or nurse about it.) Be sure to ask whether you should take medications at home—with a very small sip of water—that you nor- mally take each morning. You can expect to have an electrocardiogram (ECG), blood tests, urine tests, and a chest X-ray. Then a nurse will give you a sedative to relax you before you go to the operating room. The areas that will be operated on (your chest and leg or arm) will be washed, sterilized, and shaved if necessary.

    How Bypass Is Done

    In the operating room you will be wired to an ECG machine to moni- tor your heart . You will be given a local anesthetic before an intravenous (IV) line is placed in your arm, and then you will be given a general anesthetic. The surgery will probably take 4 to 6 hours, depending on the number and complexity of the blockages. When you are completely asleep, a breathing tube (endotracheal tube) will be inserted through your mouth and down your trachea to help you breathe and to enable nurses to clear secretions from your lungs. Another tube will be inserted through your nose and down your throat to your stomach to prevent liquid or air from entering your stomach, so that you will not feel nauseous or bloated after you wake up. A catheter (a thin tube) will be placed in your urethra (the passageway to your bladder) to collect urine during and after the procedure.
    You will be given an anticoagulant medication  such as heparin to keep your blood from clotting. Then you will be connected to the heart-lung machine, which will take over your heart’s pumping action and oxygenate your blood during the surgery, so that your heart is still and not full of blood while the surgeons work.
    The number of vessels bypassed during surgery depends on how many coronary arteries and their main branches are blocked. Your sur- geon can construct a bypass in different ways. He or she may remove a piece of a long vein in your leg (the saphenous vein) or the radial artery in your arm, neither of which is crucial to the circulation in those areas. The surgeon will stitch one end of the vessel onto your aorta (the large artery leaving your heart) close to where the coronary arteries originate, and graft the other end to the affected coronary artery below the blocked area. In effect, a new artery has been created to route blood around the blockage.
    In many cases, at least one bypass will be created using a segment of one or both of the two internal mammary arteries, located behind your breastbone on your chest wall. These arteries originate from the aorta, so the surgeon does not have to entirely remove a piece of the artery. He or she can detach one end of the artery from the chest wall and reat- tach it to the coronary artery below the blockage. Remaining arteries are able to supply the chest wall with adequate blood. These arteries are used frequently because they may have less of a tendency to develop blockages after the surgery.

    When the operation is complete, the surgeon makes sure that your heart is adequately supplied, that blood is not leaking, and that the area is soft to the touch. Also, an angiogram while you are still on the table veri?es that your arteries are not leaking internally. Then the surgeon restarts your heart with an electrical shock. The heart function is trans- ferred from the heart-lung machine back to your heart.

    Recovery in the Hospital

    After surgery you will probably spend the ?rst 1 to 3 days in the inten- sive care unit, where the staff will monitor your heart function closely. You will have a breathing tube and be connected to a ventilator for at least several hours, and you will have temporary drainage tubes in your chest to remove excess blood and ?uids. (Some people, especially those with underlying lung disease, will need to be connected to a ventilator for a longer period of time.) You will have a catheter in your neck or under your clavicle in the chest to permit monitoring of your heart function and pressure. You will also have pacemaker wires attached to the heart muscle that come out of the chest and are attached to a pace- maker generator. You will receive intravenous fluids to keep you hydrated, and you will be given pain medications.

    Some hospitals offer pain pumps that allow you to control the deliv- ery of pain medications into your vein. A small catheter is placed in your chest incision that can deliver a local anesthetic directly to the area of your surgery. You can activate the pump by pushing a button at your bedside. Studies show that when patients control their own pain med- ication, the pain is better controlled but also people tend to use less medication. Self-administered pain relief allows people to recover faster and more comfortably.
    The breathing tube is removed within hours. Most patients can get out of bed within 24 hours of bypass surgery and can walk in 1 or 2 days. When your doctor is satis?ed that your heart has stabilized, you will be able to leave the intensive care unit, and the other catheters and tubes may be removed. Some people experience a rapid, irregular heart rhythm after the surgery, but this condition can be treated with medica- tions. Or there may be slowing of the heart and if necessary, a pace- maker is installed. You will probably be strong enough to leave the hospital in 5 to 7 days.
    Complications of bypass surgery may include pneumonia, urinary tract infection, or stroke. Anemia is common after the surgery, but the body usually recovers over time. Heart rhythm disturbances may occur and require treatment with medication or the installation of a pacemaker.

    Recovery at Home

    Subsequent recovery at home generally takes several weeks until you get back to your usual self. Some people experience loss of appetite and constipation. You may feel easily tired, moody, or depressed, and it may be dif?cult to sleep. Some people experience swelling in the area from which a blood vessel was removed, such as the lower leg, and you may have some muscle pain in your shoulders and upper back. These effects are normal and will probably disappear in 4 to 6 weeks. A full recovery may take several months, in part because your breastbone must heal, which may be painful. Don’t hesitate to tell you doctor about bother- some side effects.
    Your doctor can help you determine how quickly to get back to your daily routines. He or she will probably recommend that you gradually work your way back to normal activities such as walking, going out with friends, doing light housework or yard work, and climbing stairs.

    Results of Bypass Surgery

    A coronary artery bypass operation improves symptoms such as angina for most people (about 90 percent), and it may prolong life in certain high-risk cases. Most people can return to work or to the same activi- ties they enjoyed before surgery and remain free of symptoms for many years. But bypass surgery does not cure coronary artery disease. New blockages can form in different places in the arteries, and the grafted routes can become clogged. Some branches of arteries are too small to be corrected by a bypass, and blockages in these small arteries can cause angina. Statistically, about 40 percent of people who have bypasses show signs of a new blockage in the bypass grafts within 10 years of surgery.
    Controlling the risk factors that lead to blockage is the most impor- tant way that you and your doctor can manage your coronary artery dis- ease. It is more important than ever to maintain normal weight or lose weight if necessary, quit smoking, eat a heart-healthy diet, and get reg- ular exercise. Your doctor will work with you to achieve good control of high cholesterol, high blood pressure, and diabetes. Your cardiologist will want to see you every 1 to 3 months at ?rst, and then at least annu- ally to monitor your condition.
    You will almost certainly be advised to take aspirin inde?nitely. Your doctor may also prescribe medications such as ACE inhibitors, beta- blockers, or cholesterol-lowering drugs to help control your disease and improve your heart function.

    Cardiac Rehabilitation

    A cardiac rehabilitation program, often available through a community hospital, is a medically supervised program to help you learn to live with heart disease. This program provides you with the resources to get any kind of help you need to ease your transition back to a full, sat- isfying life. It involves a commitment of time, but it probably speeds your way to a full recovery. The trained staff can work with you to tai- lor your steps toward recovery to suit you, your medical condition, and your work and family demands. Exercise in a supervised setting, with skilled medical personnel available, usually provides a level of security that helps many people achieve exercise targets more easily and sooner than they would on their own. Many insurance plans cover cardiac rehabilitation. Your cardiologist can give you information about pro- grams near you.
    A rehabilitation program usually lasts for the ?rst 3 months or so after your heart attack. It is generally organized in four phases: hospi- talization; early recovery (2 to 12 weeks after you go home); late recovery (6 to 12 weeks or more); and maintenance. The maintenance “phase” extends for the rest of your life, as your lifestyle changes become permanent and you resume your normal activities.
    A cardiac rehabilitation program will help you:
    • Gradually adjust your level of physical activity to strengthen your heart, monitoring your progress so that you can safely maximize your capacity for exercise
    • Adjust your cooking, snacking, and eating styles to focus on a low- fat, low-cholesterol diet
    • Work out a plan to balance your diet and exercise needs to control your weight
    • Get counseling or other help to quit smoking
    • Get advice about the impact of your job on your heart, and how you can take steps to protect yourself
    • Learn about techniques (such as yoga, meditation, or massage) to manage stress on and off the job
    • Deal with the emotional and psychological sides of the changes in your life
    • Talk to other people who are facing the same challenges and mak- ing the same kind of changes in their lives

  • Angioplasty

    Medications and lifestyle changes are not always enough to prevent a heart attack. A person who comes to the hospital with severe angina or a heart attack probably has one or more coronary arteries that are com- pletely blocked. The ?rst priority is to restore blood ?ow immediately, and the next concern is to reduce the risk of another heart attack. Your risk is especially high if your heart’s pumping ability has been compro- mised by damage, if you have blockages in three or more arteries, or if one of the blockages is in the left main coronary artery, which supplies the powerful left ventricle. Angioplasty, or balloon angioplasty, is a pro- cedure that opens a blocked artery by compressing the plaque against the walls of the artery to clear a wider channel.
    Angioplasty is also called percutaneous (through the skin) transluminal (in an artery) coronary angioplasty (PTCA). The procedure is done by inserting a catheter into an artery, usually in the groin, to pass it through the aorta to the heart. When the balloon reaches the site of the blockage, it is in?ated to compress the plaque.
    By opening an artery, angioplasty effectively relieves the pain of angina and minimizes damage to the heart. It may be done as an emer- gency procedure when a person arrives at the hospital in the midst of a heart attack. Angioplasty may also be performed on a nonemergency basis, to relieve angina symptoms or to try to prevent a heart attack. In the United States, more than 1.2 million angioplasties were performed in a recent year in people with coronary artery disease.
    In most cases (70 to 90 percent) of angioplasty proce- dure, the doctor will insert a stent into the artery (a device to support the walls from the inside). Some stents are cov- ered with medications that help reduce the risk of clot formation. The reason that stents are not placed in some people is the location and the type of lesion.
    The main purpose of a stent is to reduce the possibil- ity of the artery narrowing again in the same place, a process called restenosis. Restenosis occurs in about 40 percent of people with angioplasty alone, and only about 20 percent of people with angioplasty and
    stenting. For reasons that are unclear, people with diabetes are at increased risk for restenosis.
    If your doctor recommends that you have an angio- plasty, you will probably have a chest X-ray, an electro- cardiogram (see page 122), and blood tests before the procedure. You and your doctor can thoroughly discuss why you are having the angioplasty, how it will be done, and what you can expect afterward. Be sure to talk about any medications you are taking; your doctor may ask you to stop taking them—particularly antiplatelet or antico- agulant drugs—before the procedure. You will also be asked not to eat or drink anything after midnight before the procedure. If you have diabetes, talk to your doctor in detail about your medications and your food intake, because either of these factors affects your blood sugar levels

    How Angioplasty Is Done

    An angioplasty is usually done in a catheterization laboratory, often called the cath lab. Electrodes will be placed on your chest and you will be connected to an electrocardiogram machine to monitor your heart during the procedure. You do not need a general anesthetic, but you will receive an intravenous sedative. The area of your leg (or sometimes the arm) where the catheter will be inserted will be anesthetized, then cleansed and shaved. After this area is numbed, you will not feel any pain during the procedure, but you will be awake.
    The doctor will locate the appropriate artery and insert a catheter (a thin tube) through the skin. He or she will guide the catheter through the artery up the aorta and into your heart, watching its path on a monitor. When the catheter is at the opening of the coronary artery, a dye is injected so that the doctor can take an image of the arteries (an angiogram; ) and see on the monitor if there is a blockage of blood ?ow within the artery. After studying the size and extent of the blockage, he or she may insert a tiny balloon-tipped device, guide it to the site of the blockage, and then in?ate the balloon, which will expand against the walls of the artery. The in?ated balloon is kept in place for up to 2 minutes and then de?ated. The doc- tor can inflate it several times if necessary to shape the inside of the artery. When the results are satisfactory, the de?ated balloon and catheter are removed.
    How Stents Are Placed

    A stent is a piece of tubing made of springy wire mesh. It is placed over the balloon on the tip of the catheter and guided into position in the cleared artery. Then the balloon is in?ated and the stent expands, locks in place, and props the artery open, with the compressed plaque behind it. The balloon is de?ated and removed, and the stent remains permanently. Within a few weeks, new tissue forms over the surface of the stent so that the interior passageway is smooth. Stenting can be done alone, but is usually done in combination with angioplasty. The surgeon can work on several blocked arteries during one procedure.

    After the Procedure

    An angioplasty procedure is likely to last from 45 minutes to more than
    2 hours. After the procedure is done and the catheter is removed, the doctors or nurses will stop the bleeding by applying pressure, either manually or with specially designed pressure devices, for 20 minutes or more over the place where the catheter was inserted, and then will bandage the area. You will feel sleepy until the sedative wears off. You will be asked to lie very still during the recovery period for up to 8 hours. A nurse will monitor your heart and blood pressure and will check the incision site fre- quently for signs of excessive bleeding or damage to the blood ?ow through the artery. You will probably spend from 1 to 2 days in the hospital.
    You will have to arrange to have someone drive you home, and you should not drive for several days after- ward, while the incision is still healing. Your doctor will ask you not to bathe, or stand and walk for long periods of time, for at least 2 days after the procedure. Once you get home, call your doctor promptly if you see any bleeding or swelling at the site of the incision or if you have a fever, which is a possible sign of an infection. If you have a stent, you should probably avoid exercising vigorously for about 30 days. However, there are many cases on record of people returning to work or exercise

    sooner than that; ask your doctor what is best for you.
    Your doctor may prescribe medications such as nitroglycerin to relax the coronary arteries, calcium antagonists to guard against coronary artery spasm , or aspirin and other antiplatelet drugs to prevent blood clots in the area of the blockage. If you have a stent, you will have to take blood thinners (such as aspirin) inde?nitely. You will also take an antiplatelet such as clopidogrel  at least one month after a bare-metal stent is placed in your artery and two or more years after a drug-eluting stent is placed in your artery. Because of the presence of the metal stent, you should not have magnetic resonance imaging (MRI) for at least 4 weeks with- out checking with your doctor ?rst. But you can go through a metal detector at an airport without a problem.

    Restenosis

    Restenosis (renarrowing or constriction) can occur in the same area of the blood vessel where your angioplasty was done, often within about 6 months of the original procedure. Although placement of a stent greatly reduces the likelihood that this will happen, restenosis can occur in an artery with a stent (in-stent restenosis). The artery becomes blocked again because, in addition to the healthy new tissue that forms over the stent, scar tissue can develop under the surface that becomes so thick it obstructs the blood ?ow again. People with diabetes have a higher risk of restenosis, but it can occur in other patients as well, depending in part on the location of the blockage and the pattern of scar tissue growth.
    If a restenosis occurs, the person is likely to experience the same types of symptoms (chest pain after exertion) that he or she felt before the ?rst angioplasty was done. (A patient with diabetes may have fewer or less typical symptoms.) Fortunately, restenosis very rarely causes a heart attack. Your doctor will be watching closely to detect restenosis and to check for blockages in other arteries by monitoring your symp- toms and having you take a follow-up exercise stress test. Be sure to report promptly any symptoms that you experience after your angio- plasty. If a restenosis does occur, another angioplasty or bypass surgery may be required to correct the blockage.
    Of course, doctors are searching for ways to prevent restenosis. A major advance has been the development of drug-eluting stents—that is, devices that are coated with slow-release medications that penetrate the surrounding tissue to prevent the growth of scar tissue. Drug- eluting stents appear to substantially improve the long-term success of angioplasty procedures, though they also increase the short-term risk of clot formation. If you have a drug-eluting stent, you will need to take clopidogrel for at least two years and aspirin inde?nitely. Before sur- gery, ask your cardiologist if a bare-metal stent or drug-eluting stent is best for you.
    Doctors at some medical centers are working with a procedure called brachytherapy, which uses radiation to stop tissue growth around a stent. A catheter with a radioactive tip is threaded into the blockage around a stent and a dose of radiation is administered. Although the radiation lasts only about 10 minutes, it inhibits long-term growth of tissue. Brachytherapy is not widely available, however, and needs study.
    You can help protect yourself from restenosis by leading a heart- healthy lifestyle after angioplasty. Quit smoking, eat a low-fat diet, get regular exercise, take your medications, and follow up regularly with your physician to contribute to the success of your angioplasty. A car- diac rehabilitation program will offer advice and support to help you incorporate these vital changes into your life .

  • Medications to Treat Blood Clots

    Blood clots often play a prominent role in cardiovascular disease. In a healthy person, specialized blood cells called platelets have the capacity to form a clot in response to injury, as a way to limit loss of blood. How- ever, in a person with cardiovascular disease, a blood clot that forms abnormally in an artery leading to the heart can cause a heart attack (myocardial infarction), and one that travels to an artery leading to the brain can cause a stroke .
    In a person with coronary artery disease, the plaque that builds up in the coronary arteries can be destabilized by factors such as high blood pressure, high blood sugar, or the toxic ingredients in tobacco. A type of plaque called soft plaque (see page 154) can rupture, and the platelets respond as they would to an injury, by forming a clot over the damaged area. A blood clot in an already clogged artery can block the blood ?ow completely, causing a heart attack.

    Thrombolytic Agents

    Thrombolytic agents (“clot busters”) dissolve clots in the arteries, restoring blood ?ow to heart tissue. Their use has substantially reduced disability and death from heart attacks and strokes. These drugs (including streptokinase, urokinase, and tissue plasminogen activator, or tPA, used for strokes) can be given as soon as you have been diagnosed as having a heart attack or stroke, either because of your symptoms or in response to the results of an electrocardiogram. If you get to a hos- pital immediately and the thrombolytics go to work within 4 to 6 hours of the onset of your symptoms, you are very likely to have only minimal damage to your heart function. If too much time passes before the thrombolytics are given, the damage is already done and restoring blood ?ow will not revive the tissue.
    Emergency department personnel administer thrombolytic agents intravenously. The most serious drawback of these drugs is that they do not distinguish an abnormal blood clot from a useful one. You cannot receive them if you have a condition that might cause a bleeding prob- lem, such as a stomach ulcer, a recent injury or surgical procedure, or a recent stroke.

    Antiplatelets

    Antiplatelet drugs interfere with platelet function and the formation of blood clots. Platelets are the elements within the blood that stick together and form clots. Some drugs (such as aspirin) are used to prevent clot formation in people at high risk of heart attack. Some types are given if you are having uncontrolled chest pain (unstable angina) or during or immediately after a heart attack to reduce recur- rence. Antiplatelets are also given after an angioplasty, insertion of a stent, or bypass surgery to prevent clots from forming inside the vessel.
    Clotting is a chemically complex process, and different antiplatelet agents disrupt speci?c stages of clot formation. They are used alone or in combination to treat different types of heart attacks or under various circumstances.
    Aspirin is the most familiar antiplatelet drug. Because it is inexpensive, effective, and easy to take by mouth, it is often the first treatment given at the onset of heart attack symptoms, even before you get help from emergency medical services .

    Taking aspirin right after a heart attack may improve survival rates by as much as 20 percent. At the hospital, other antiplatelets (such as clopidogrel or glycoprotein inhibitors) may also be given, either orally or intra- venously. Doctors are learning more all the time about how to use these drugs to bene?t more patients.
    Because all antiplatelet drugs interfere with normal blood clotting, the main risk of taking them is bleed- ing. The bleeding is usually very minor, such as skin bruising or nosebleed. In people who are being treated in a hospital for heart attacks, the most common sites of bleeding are where catheters have been inserted— for example, in the groin where an access catheter is inserted for angioplasty. This type of bleeding is usu- ally easily controlled by applying pressure to the site. Rarely, bleeding occurs from another source such as a stomach ulcer.

    Anticoagulants

    Anticoagulants are used to prevent the forming or growth of a blood clot by interfering with the clotting process. But they do not dissolve an existing blood clot, as a thrombolytic agent does. Although they are commonly called blood thinners, they do not really thin your blood; they just reduce the blood’s ability to clot. These agents, such as war- farin, are stronger than the antiplatelet medications. Therefore, your doctor’s of?ce will need to do careful and frequent monitoring—in the form of a blood test—of the clotting factor in your bloodstream. This is vital to prevent bleeding complications and to ensure adequate clot- ting effect.
    If you have had a heart attack, you are at greater risk of developing a blood clot near the site of a clot that was dissolved by a thrombolytic agent. If severe damage occurred in your left ventricle, a clot could also form there, where it can cause serious complications, and your doctor may prescribe warfarin. Also, if you are in bed for a long time after a heart attack, blood clots can develop in your legs. Anticoagulants help prevent all these possibilities.
    Heparin, which is administered intravenously in the hospital, is a powerful and well-established anticoagulant for heart attack patients. If you undergo a procedure such as angioplasty, heparin will be adminis- tered to prevent clots from developing at the site of the procedure. The dosage must be carefully adjusted and its use must be monitored closely. A new type of heparin, called low-molecular-weight heparin, has been developed that is injected and does not require as much monitoring. Any form of heparin can cause unintended bleeding as a side effect. After an angioplasty, stronger clot-preventing medications such as clopidogrel may be prescribed.

    Aspirin for Heart Disease

    For some people, taking aspirin regularly is a means of preventing the recurrence of certain types of heart symptoms or events. Your doctor may recommend aspirin if you have had a heart attack, a transient ischemic attack , or an ischemic stroke , or if you have had trouble with recurring angina (chest pain; ). Some studies even suggest that aspirin may help prevent a ?rst occurrence of some of these events. Aspirin helps ensure adequate blood ?ow and may reduce the likelihood of clot formation. Aspirin works by slowing down the work of platelets in your bloodstream; when platelets are less sticky, clots are less likely to form. Aspirin may also help protect against the in?ammation of arteries that occurs with atherosclerosis and may help prevent heart attacks in people with diabetes.
    Taking aspirin regularly is different from taking it occasionally for something like a headache, and it poses some risks. You should not start taking aspirin for your heart without talking to your doctor ?rst. In evaluating whether aspirin ther- apy is right for you, your doctor will consider your medical and family history; other drugs you may take, including vitamin or herbal supple- ments; allergies; the likelihood of certain side effects such as stomach bleeding; the relative risk versus bene?t; and what dose is right. If you have some medical conditions such as bleeding disorders, asthma, ulcers, or kidney disease, aspirin may not be a safe choice.
    If your doctor recommends aspirin, it’s important to take it exactly as he or she directs so that you get the desired bene?t, and the chance of side effects is minimized. The instructions on the aspirin bottle are intended for general use, not for heart patients, so do not follow them. But read the label on the product you buy to be sure that it contains aspirin in the correct amount recommended by your doctor. Check the drug facts label for “active ingredients: aspirin” or “acetylsalicylic acid.” If you experience any adverse effects after you start taking aspirin—such as stomach pains, indigestion, cramps, or black tarry stools (a sign of internal bleeding)—tell your doctor immediately.

    WARNING!

    Aspirin during a Heart Attack or a Stroke

    If you are having warning signs of a heart attack (such as chest pain), the most important thing to do is to call 911 or the emergency number for your area. Do not take an aspirin to see if it will relieve the pain before calling 911. Although aspirin will not treat a heart attack by itself, many experts recom- mend chewing one adult aspirin if you think you may be having a heart attack. Of course, if you are allergic to aspirin or have a condition that prevents you from taking aspirin, then wait until you get advice from a doctor. The 911 emergency operator may ask you about allergies and then recommend that you take an aspirin, or the emergency medical technicians may give you one in addition to other treatments. A single adult aspirin may reduce the chance of dying from a heart attack by about 20 percent, making it one of the most cost-effective life-saving measures in medicine.
    If you or a family member is having a stroke, do not take or administer an aspirin, because not all strokes are caused by blood clots. The emergency department is best qualified to make a judgment about whether aspirin might be effective for the particular type of stroke.

  • Blood Ammonia

    One function of the liver is the synthesis of urea from various sources of ammonia, most of which come from protein-splitting bacteria in the GI tract. In cirrhosis, there is extensive liver cell destruction and fibrous tissue replacement of areas between nodules of irregularly regenerating liver cells. This architectural distortion also distorts the hepatic venous blood supply and leads to shunting into the systemic venous system, a phenomenon often manifested by esophageal varices. Thus, two conditions should exist for normal liver breakdown of ammonia: (1) enough functioning liver cells must be present and (2) enough ammonia must reach these liver cells. With normal hepatic blood flow, blood ammonia elevation occurs only in severe liver failure. With altered blood flow in cirrhosis, less severe decompensation is needed to produce elevated blood ammonia levels. Nevertheless, the blood ammonia is not directly dependent on the severity of cirrhosis but only on the presence of hepatic failure.

    Hepatic failure produces a syndrome known as “prehepatic coma” (hepatic encephalopathy), which progresses to actual hepatic coma. Clinical symptoms of prehepatic coma include mental disturbances of various types, characteristic changes on the electroencephalogram, and a peculiar flapping intention tremor of the distal extremities. However, each element of this triad may be produced by other causes, and one or more may be lacking in some patients. The ensuing hepatic coma may also be simulated by the hyponatremia or hypokalemia that cirrhotic patients often manifest or by GI bleeding, among other causes. Cerebrospinal fluid glutamate levels are currently the most reliable indicator of hepatic encephalopathy. However, this requires spinal fluid, and in addition, the test is often not available except in large medical centers or reference laboratories. Of more readily available laboratory tests, the blood ammonia level shows the best correlation with hepatic encephalopathy or coma. However, the blood ammonia level is not elevated in all of these patients, so that a normal blood ammonia level does not rule out the diagnosis. Arterial ammonia levels are more reliable than venous ones since venous ammonia may increase to variable degree compared to arterial values. RBCs contain about 3 times the ammonium content of plasma, so that hemolysis may affect results. Muscular exertion can increase venous ammonia. Plasma is preferred to serum since ammonia can be generated during clotting. Patient cigarette smoking within 1 hour of venipuncture may produce significant elevation of ammonia. One investigator reported transient ammonia elevation at 0.5-3 hours and again at 3.5-6 hours after a meal containing protein in some normal persons, with the effect being magnified in persons with liver disease.

    Blood ammonia has been proposed as an aid in the differential diagnosis of massive upper GI tract bleeding, since elevated values suggest severe liver disease and thus esophageal varices as the cause of the bleeding. However, since cirrhotics may also have acute gastritis or peptic ulcer, this use of the blood ammonia level has not been widely accepted. At present, the blood ammonia is used mainly as an aid in diagnosis of hepatic encephalopathy or coma, since elevated values suggest liver failure as the cause of the symptoms. Otherwise, ammonia determination is not a useful liver function test, since elevations usually do not occur until hepatic failure.

  • Serum Proteins

    Serum albumin levels decrease to variable degrees in many severe acute and chronic disorders. Albumin is synthesized in the liver, so most acute or chronic destructive liver diseases of at least moderate severity also result in decreased serum albumin levels. In addition, there may be other serum protein changes. In cirrhosis of moderate to severe degree, there is a decreased albumin level and usually a “diffuse” (“polyclonal”) gamma-globulin elevation, sometimes fairly marked. About 50% of patients with well-established cirrhosis have a characteristic serum protein electrophoretic pattern with gamma-globulin elevation that incorporates the beta area (so-called beta-gamma bridging). However, about 35% of cirrhotic patients show only various degrees of gamma elevation without any beta bridging, and about 10% have normal gamma levels. Hepatitis may also be associated with moderate elevation of the gamma globulins. Biliary obstruction eventually causes elevated beta-globulin levels, since beta globulins carry cholesterol.