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  • Liver Biopsy

    This procedure has been greatly simplified, and its morbidity and mortality markedly reduced, by the introduction of small-caliber biopsy needles such as the Menghini. Nevertheless, there is a small but definite risk. Relative contraindications to biopsy include a PT in the anticoagulant range or a platelet count less than 50,000/mm3. Liver biopsy is especially useful in the following circumstances:

    1. To differentiate among the many etiologies of liver function test abnormality when the clinical picture and laboratory test pattern are not diagnostic. This most often happens when the AST level is less than 10 or 20 times the upper reference limit and the ALP level is less than 3 times the upper limit. In cases of possible obstructive jaundice, extrahepatic obstruction should be ruled out first by some modality such as ultrasound.
    2. To prove the diagnosis of metastatic or primary hepatic carcinoma in a patient who would otherwise be operable or who does not have a known primary lesion (in a patient with an inoperable known primary lesion, such a procedure would be academic).
    3. In hepatomegaly of unknown origin whose etiology cannot be determined otherwise.
    4. In a relatively few selected patients who have systemic diseases affecting the liver, such as miliary tuberculosis, in whom the diagnosis cannot be established by other means.

    A discussion of liver biopsy should be concluded with a few words of caution. Two disadvantages are soon recognized by anyone who deals with a large number of liver specimens. First, the procedure is a needle biopsy, which means that a very small fragment of tissue, often partially destroyed, is taken in a random sample manner from a large organ. Localized disease is easily missed. Detection rate of liver metastases is about 50%-70% with blind biopsy and about 85% (range, 67%-96%) using ultrasound guidance. Second, many diseases produce nonspecific changes that may be spotty, may be healing, or may be minimal. Even with an autopsy specimen it may be difficult to make a definite diagnosis in many situations, including the etiology of many cases of cirrhosis. The pathologist should be supplied with the pertinent history, physical findings, and laboratory data; sometimes these have as much value for interpretation of the microscopic findings as the histologic changes themselves.

    In summary, liver biopsy is often indicated in difficult cases but do not expect it to be infallible or even invariably helpful. The best time for biopsy is as early as possible after onset of symptoms. The longer that biopsy is delayed, the more chance that diagnostic features of the acute phase have disappeared or are obscured by transition to healing.

  • Endoscopic Retrograde Choledochopancreatography

    Endoscopic retrograde choledochopancreatography entails passing a special endoscopic tube system into the duodenum, entering the pancreatic duct or the common bile duct with the end of a cannula, and injecting x-ray contrast material. The procedure is used predominantly for diagnosis of pancreatic disease, but it may occasionally be helpful in equivocal cases of biliary tract obstruction. Cannulating the common bile duct is not easy, and best results are obtained by very experienced endoscopists.

  • Percutaneous Transhepatic Cholangiography

    Percutaneous transhepatic cholangiography consists of inserting a cannula into one of the intrahepatic bile ducts through a long biopsy needle and injecting x-ray contrast material directly into the duct. This procedure outlines the biliary duct system and both confirms biliary tract obstruction by demonstrating a dilated duct system and pinpoints the location of the obstruction. The technique is not easy and requires considerable experience; more than 25% of attempts fail (most often in patients with intrahepatic obstruction due to liver cell damage). There is a definite risk (although very small) of producing bile peritonitis, which occasionally has been fatal. Preparation for surgical intervention should be made in advance in case this complication does develop.

  • Computerized Tomography and Ultrasound

    Ultrasound has been reported to detect metastatic liver tumor in approximately 85%-90% of patients (literature range, 63%-96%, with some of the lower figures being earlier ones). Computerized tomography (CT) has a sensitivity of 90%-95%. Radionuclide scans detect a few more patients with diffuse liver abnormality than CT or ultrasound. However, CT and ultrasound can differentiate cysts from solid lesions in the liver, which both look the same on radionuclide scanning. CT can also detect abnormalities outside the liver as incidental findings to a liver study. Ribs may interfere with ultrasound examination of the liver dome area, and gas in the hepatic flexure of the colon can interfere in the lower area of the liver. Magnetic resonance imaging (MRI) has about the same detection rate as CT but is much more expensive and at times has some problems with liver motion due to relatively slow scan speed.

    CT and ultrasound are important aids in differentiating extrahepatic from intrahepatic biliary tract obstruction through visualization of the diameter of the intrahepatic and common bile ducts. In complete extrahepatic obstruction, after a few days the common bile duct becomes dilated; in most cases the intrahepatic ducts eventually also become dilated. In intrahepatic obstruction the common bile duct is not dilated. Ultrasound has asensitivity of about 93% (literature range, 77%-100%), and CT is reported to have a sensitivity of about 94% (literature range, 85%-98%). There have also been considerable advances in the ability of ultrasound and CT to demonstrate the approximate location of obstruction in the biliary system as well as making an overall diagnosis of obstruction. Gas in the intestine may interfere with ultrasound in a few cases.

    In general, most investigators believe that ultrasound is the procedure of choice in possible biliary tract obstruction; those few cases that are equivocal or technically inadequate with ultrasound can be studied by CT or some other technique such as percutaneous transhepatic cholangiography.

  • Radionuclide Liver Scan

    If a radioactive colloidal preparation is injected intravenously, it is picked up by the reticuloendothelial system. The Kupffer cells of the liver take up most of the radioactive material in normal circumstances, with a small amount being deposited in the spleen and bone marrow. If a sensitive radioactive counting device is placed over the liver, a two-dimensional image or map can be obtained of the distribution of radioactivity. A similar procedure can be done with thyroid and kidney using radioactive material that these organs normally take up (e.g., iodine in the case of the thyroid). Certain diseases may be suggested on liver scan if the proper circumstances are present:

    1. Space-occupying lesions, such as tumor or abscess, are often visualized as discrete filling defects if they are more than 2 cm in diameter.
    2. Cirrhosis typically has a diffusely nonuniform appearance accompanied by splenomegaly, but the cirrhotic process usually must be well established before scan abnormality (other than hepatomegaly) is seen. The most typical picture is obtained in far-advanced cases, but the scan appearance may differ somewhat even in these patients.
    3. Fatty liver has an isotope distribution like that of cirrhosis, but only if severe.
    4. Liver scanning may be useful to differentiate abdominal masses from an enlarged liver.

    Undoubtedly, more sensitive equipment will become available and, perhaps, better radioactive isotopes. At present, useful as the liver scan may be, it is often difficult to distinguish among cirrhosis, fatty liver, and disseminated metastatic carcinoma with nodules less than 2 cm in diameter. Liver scan is reported to detect metastatic carcinoma in 80%-85% of patients tested (literature range, 57%-97%) and to suggest a false positive diagnosis in 5%-10% of patients without cancer. The majority of these false positive studies are in patients with cirrhosis, hepatic cysts, hemangiomas, or a prominent porta hepatis.

  • Alpha Fetoprotein Test (AFP)

    Fetal liver produces an alpha-1 globulin called “alpha fetoprotein” (AFP), which becomes the dominant fetal serum protein in the first trimester, reaching a peak at 12 weeks, then declining to 1% of the peak at birth. By age 1 year, a much greater decrease has occurred. Primary liver cell carcinomas (hepatomas) were found to produce a similar protein; therefore, a test for hepatoma could be devised using antibodies against AFP antigen. Original techniques, such as immunodiffusion, were relatively insensitive and could not detect normal quantities of AFP in adult serum. Extensive studies using immunodiffusion in several countries revealed that 30%-40% of European hepatoma patients who were white had positive test results, whereas the rate among Chinese and African Americans with hepatoma was 60%-75%. Men seemed to have a higher positive rate than women. Besides hepatoma, embryonal cell carcinoma and teratomas of the testes had an appreciable positivity rate. Reports of false positive results with other conditions included several cases of gastric carcinoma with liver metastases and a few cases of pregnancy in the second trimester. Subsequently, when much more sensitive radioimmunoassay techniques were devised, small quantities of AFP were detected in normal adult individuals. RIA and EIA have increased the abnormality rate in hepatoma somewhat, especially in European patients, whereas elevations accompanying other conditions are also more frequent. For example, according to one report, AFP levels were increased in approximately 75% of hepatoma cases, 75% of embryonal carcinomas or teratomas of the testes, 20% of pancreatic or gastric carcinomas, and 5% of colon and lung carcinomas. Others have found AFP elevations by immunoassay methods in 90% or more of hepatomas (literature range, 69%-100%) and in 0%-5% of various nonneoplastic liver diseases. The most frequent nonneoplastic elevations occurred in conditions associated with active necrosis of liver cells, such as hepatitis and active alcoholic cirrhosis. An AFP level of 500 ng/ml was suggested by several investigators as a cutoff point in differentiating hepatoma from nonneoplastic liver disease. Almost all of the nonneoplastic disease (except some cases of hepatitis virus hepatitis) were less than 500 ng/ml, whereas 50% or more patients with hepatoma had values higher than this.

  • Cell Component Autoantibodies

    Antibodies that react against specific structures in cells can be demonstrated by immunofluorescent technique. Antimitochondrial antibodies are found in 80%-100% of biliary cirrhosis patients and may aid in the diagnosis of this uncommon disease. False positive results have been reported in some patients with drug-induced cholestasis and chronic active hepatitis, as well as in a relatively small number of patients with extrahepatic obstruction, acute infectious hepatitis, rheumatoid arthritis, and other conditions. There are subgroups of antimitochondrial antibodies; the M-2 subgroup is claimed to be specific for primary biliary cirrhosis. However, it is very difficult to obtain testing for M-2 alone. Anti-smooth muscle antibodies were reported in 45%-70% of patients with chronic active (“lupoid”) hepatitis but have also been found in biliary cirrhosis and, less frequently, in other liver diseases (except alcoholic cirrhosis). An immunofluorescence expert is needed to set up and interpret these procedures. Liver biopsy is still needed.

  • Repair or Replacement of Heart Valves

    The vast majority of procedures to repair or replace heart valves are done on the mitral and aortic valves on the left side of the heart. The mitral valve controls in?ow and the aortic valve controls out?ow for the hard-working left ventricle that pumps blood to the rest of the body. These two valves are more prone to disease, and they are also more crit- ical to the overall function of the heart.
    The progress of valve disease in any one person can be unpredictable, so the course and timing of your treatment involves individualized decision making. If you are not having symptoms, or if your valve irregularity is not affecting your heart’s function negatively, your cardiologist may choose just to watch your condition carefully.
    For badly damaged and narrowed valves, valvu- loplasty (opening a valve with a balloon-tipped catheter), or surgical repair or replacement may be necessary. A valvuloplasty is a less invasive procedure, because the repair is done using a catheter threaded into your heart through an artery. Other types of repair or valve replacement almost always involve open-heart surgery, meaning you are given a general anesthetic, the breastbone is divided, and a heart-lung machine  takes over the function of your heart during the procedure.

    Usually, your cardiologist and a thoracic (chest) surgeon will work together to determine what type of procedure is required, and when to do it. Even if you don’t have any symptoms, these procedures are some- times necessary to prevent damage to your heart.

    Valvuloplasty

    Valvuloplasty, which uses a balloon catheter to open a valve, is most often done to correct moderate to severe mitral valve stenosis. It can also be done on the tricuspid and pulmonary valves, and rarely, the aortic valve. The procedure is done in a catheterization laboratory rather than an operating room and is similar in many ways to balloon angioplasty done on coronary arteries .
    You will be given a local anesthetic at the site where the catheter will be inserted, usually in the groin. The surgeon makes a small incision and threads a balloon-tipped catheter (a thin tube) into an artery or vein. To open a mitral valve, he or she guides the catheter up into the right atrium of the heart, piercing through the atrial septum (the wall that separates the right and left atria), and through the left atrium into the mitral valve. He or she in?ates the balloon, which opens up the stiffened or fused valve lea?ets, pushes aside and compresses any calcium deposits, and stretches the valve opening. Then the balloon is de?ated and the catheter is removed. The hole in the atrial septum will heal by itself.
    There is some risk that the valve will close up again or leak some- what after the procedure. But after a successful valvuloplasty, you can probably enjoy a lifestyle as active as your lifestyle before the procedure, if not more so.

    Other Types of Valve Repair

    Other types of valve repair are open-heart surgical procedures. A sur- geon may ?x a valve in several ways:
    • Commissurotomy is a procedure to open a narrowed (stenotic) valve by cutting between thickened or fused lea?ets along their natural edges (called commissures).
    • Annuloplasty reshapes and strengthens a regurgitating (leaking) valve by inserting a ring device that supports the valve opening and enables it to close tightly. The valve is also surgically repaired.

    • Cutting out part of a lea?et and then sewing the remaining tissue back together may enable the valve to close more tightly. Some- times holes or tears in a lea?et can be patched.
    • Repairing supporting muscles (chordae tendoneae) that are torn or stretched may allow the lea?ets to close fully.
    • Removing calcium buildup from leaflets may improve valve closure.
    Repairing your own valve instead of replacing it may produce better, longer-lasting results and minimize complications such as blood clot- ting. But repair may not be possible if valves are badly damaged or are degenerated from calci?cation. If a person had rheumatic fever, the dis- ease can continue even after repair. Some mitral regurgitation caused by coronary artery disease is particularly dif?cult to treat successfully with- out replacing the valve.

    Valve Replacement

    If valve repair or valvuloplasty is not feasible or successful, a surgeon can remove your heart valve and replace it with either a mechanical or a biological substitute (prosthesis). A mechanical valve is made of metal and plastic; a biological valve (bioprosthesis) is made from animal or human tissue. Each type has some advantages and disadvantages that you and your doctor need to consider.
    Mechanical valves offer the practical advantage of durability: even if they are placed in a young person, they are likely to last a lifetime. Many models are available; your surgeon may prefer one model over another because of the procedure required to place it, but from your point of view, there is little if any difference between these products. However, there is a tendency for blood to clot around any mechanical valve. A blood clot could clog the valve, or break off and travel elsewhere in the body (including the brain, which could cause stroke). As a result, anyone with a mechanical valve must take warfarin, an anticoagulant med- ication (see page 172), for life.
    A biological valve, unlike a transplanted heart, is not living tissue and usually does not cause rejection problems. The natural tissue is sterilized and treated with preservatives. Several options are available: an animal tissue valve (xenograft or heterograft), usually the aortic valve of a pig; a human valve (allograft), retrieved from someone who has died; or more rarely, the person’s own valve (autograft)— for example, the pulmonary valve is moved from the right side of the heart to replace the aortic valve on the left—in what is known as the Ross procedure. (The pulmonary valve is then replaced with a prosthesis.) The main advantage of a biological valve is that it is much less likely to cause clotting than a mechanical valve. You may need to take anticoagulants for several weeks or months after the procedure, but not permanently. How- ever, the tissue is not as strong as a mechanical valve and more likely to calcify over time. An animal valve might need to be replaced in 10 to 15 years (or even sooner in a child or young adult). A human valve might last longer, but may not be readily available.
    Generally, a mechanical valve is a practical choice for a person under 70 years of age who can safely take anticoagulants. A biological valve may be a good choice for an older person, particularly if he or she cannot tolerate anticoagulants, or for a woman who plans to become pregnant (because taking anticoagu- lants during pregnancy is not safe).
    The risks of valve replacement surgery depend on your age, the overall condition of your heart, and other medical conditions. After suc- cessful surgery, you will probably be able to return to a normal level of exercise. Any arti?cial heart valve is subject to infective endocarditis, so you will need to take antibiotics before dental or surgical procedures .

    What to Expect

    If you and your doctor decide that repair or replacement of a heart valve is the best option for you, you will probably be able to schedule the operation at a time that is best for you (rather than having an emer- gency procedure). As for any surgical procedure, do not hesitate to dis- cuss any questions or concerns with your cardiologist and your surgeon. Make sure that they know about all medications you are taking, includ- ing over-the-counter drugs such as aspirin. If you smoke, your doctor will recommend that you quit at least 2 weeks (but preferably 6 weeks) before surgery, because smoking can lead to problems with blood clotting and breathing.

    You will probably be admitted to the hos- pital the day before surgery or the morning of the procedure. Because general anesthesia is safest on an empty stomach, you will be told not to eat anything after midnight. (If you do, be sure to tell a doctor about it.) You will probably have a chest X-ray, blood tests, urine tests, and an electrocardiogram before the procedure, and you will be given a mild seda- tive to relax you before you go into the oper- ating room. Your chest will be washed, treated with antiseptic, and shaved if necessary.
    You will be given a local anesthetic to numb your arm, and an intravenous line will be inserted to give you anesthesia. After you

    are completely anesthetized, a tube will be placed down your trachea (windpipe) to connect you to a respirator, and another tube will be threaded through your nose and down your esophagus into your stom- ach to remove air and ?uids from your stomach. A catheter (thin tube) will be inserted in your urethra and up into your bladder to collect urine during the operation and recovery.
    Your breastbone will be divided to expose your heart. A heart-lung machine will take over the function of your heart during surgery, so that your heart is immobile while the surgeon works. You will be given anticoagulant medications to prevent your blood from clotting.
    Depending on the extent of surgery, the operation will take from 2 to 4 hours. When the valve repair or replacement is complete, your heart will be started again and the heart-lung machine will be disconnected. Most people spend 1 to 3 days in the intensive care unit and about a week in the hospital.
    Your recovery from valve surgery may take several months, as your breastbone mends and your heart adjusts. Your doctor will advise you about physical activity, and he or she may recommend a cardiac rehabil- itation program. You may be able to go back to work in
    1 to 4 months, depending on the physical demands of your job. You may need to take anticoagulant medications, either temporarily or permanently, if you have had a mechanical valve replacement.

    Some people who have mechanical valves can occasionally hear a clicking sound in their chest—the sound of the new valve at work. This is a perfectly normal, and even reassuring, sign that the valve is working properly.
    Valve repair or replacement is usually successful. Failure of a new valve is rare, but if you experience signs of valve failure (basically, the symptoms of valve problems, described earlier), tell your doctor imme- diately. You will also need to be on the alert for signs of infection, such as fever, weakness, chest pain, and shortness of breath. Endocarditis can affect arti?cial valves as well as natural ones.

  • Medications for Valve Disease

    Although medications cannot “?x” a diseased valve, they can help ease your symptoms, reduce the load on your heart as it works to compen- sate for a damaged valve, and regulate your heart’s rhythm if it is dis- turbed by abnormal blood ?ow.
    Digitalis (digoxin) is frequently prescribed for a person with valve disease to strengthen the contraction of the heart muscle and slow the heart rate. It is also used to treat congestive heart failure and some types of arrhythmia such as atrial ?utter or atrial ?brillation. Derived from the foxglove plant, digitalis is a powerful drug that has been used medically for more than 200 years. Your doctor will discuss with you exactly how much digitalis you are to take, and it is important to follow instructions carefully. Other medicines you take can interact with digitalis, so be sure to tell your doctor about all other prescription and over-the-counter drugs you use. Also, be sure your doctor knows about any allergies you have or other medical problems such as diseases of the thyroid, liver, lung, or kidney.
    Your doctor also may prescribe diuretics (water pills), which promote the removal of ?uids by the kidneys. This medication decreases blood pressure and eases the workload on your heart. Blood tests may be needed to check for electrolyte loss from the diuretics.
    Anticoagulant medications help prevent blood clots, particularly if you have an irregular heart rhythm (atrial ?brillation) or have had heart valve surgery and have a mechanical replacement valve . Beta-blockers can regulate your heart rate and lower your blood pressure. Calcium channel blockers alter the muscular contractions of your heart and lower your blood pressure. By easing the workload on your heart, these drugs may help postpone the need for heart valve surgery, or enable you to avoid it altogether.

  • Pulmonary Valve Problems

    The pulmonary valve controls the blood ?ow between the right ventri- cle and the pulmonary artery leading into the lungs . Although disease is rare, the pulmonary valve can develop regurgitation (backward leakage) or stenosis (narrowing).

    Pulmonary Regurgitation

    Pulmonary regurgitation is a condition in which some blood is allowed to leak back from the pulmonary artery into the right ventricle. It is usually caused by congenital (present since birth) disease or pulmonary hypertension (high blood pressure in the lungs and right side of the heart). It is often associated with congenital heart disease affecting other parts of the heart. Very rarely, infective endocarditis (see page 192) damages the valve.
    Many people with some pulmonary regurgitation do not have symp- toms of the condition. Your doctor will monitor your heart regularly to ensure that the right ventricle is not becoming strained or enlarged. You will probably not need to limit your physical activities. If you have a valve that has been malformed since birth, you are at greater risk of infective endocarditis and may need to take antibiotics before dental or surgical procedures (see page 194).
    If the regurgitation becomes serious, it causes the right ventricle to start to fail. Then you may experience symptoms such as shortness of breath, especially during exercise; fatigue; chest pain; or leg swelling. Arrhythmias may occur. Ask your doctor about any exercise restrictions. You may require surgery to repair or replace the valve .

    Pulmonary Stenosis

    Pulmonary stenosis is a condition in which the pulmonary valve (or the artery just beyond the valve) is narrowed, reducing the ?ow of blood into the lungs. It is usually present at birth and may progress in childhood or not until later in life. If it occurs later in life, it may have been caused by rheumatic fever , congenital heart disease, or infective endocarditis.
    Pulmonary stenosis can be very mild or moderate, and it usually does not cause severe symptoms. Your doctor will check your heart regularly, watching for signs of strain on your right ventricle. You may not need to limit your physical activity, but you are at greater risk of infective endocarditis, so you will need to take antibiotics before having some dental and surgical procedures .
    If the condition is severe, it may cause symptoms such as shortness of breath, especially during exercise; fatigue; chest pain; or rarely, a bluish skin tone. Severe stenosis could cause life-threatening failure of the right ventricle. Sometimes surgery to repair the valve is done early, dur- ing the preschool years of a child’s life. In an older person, balloon valvuloplasty is usually needed to open the valve, or rarely, valve replacement  may be necessary.