Sunday, August 31, 2008

Congenital Heart Disease

Congenital heart disease is a type of defect or malformation in one or more structures of the heart or blood vessels that occurs before birth.

These defects occur while the fetus is developing in the uterus and affect 8-10 out of every 1,000 children.

Congenital heart defects may produce symptoms at birth, during childhood and sometimes not until adulthood.

About 500,000 adults in the U.S. have congenital heart disease.

What Causes Congenital Heart Disease?

In the majority of people, the cause of congenital heart disease is unknown. However, there are some factors that are associated with an increased chance of getting congenital heart disease. These risk factors include:

  • Genetic or chromosomal abnormalities in the child such as Down syndrome.
  • Taking certain medications or alcohol or drug abuse during pregnancy.
  • Maternal viral infection, such as rubella (German measles) in the first trimester of pregnancy.

The risk of having a child with congenital heart disease is higher if a parent or a sibling has a congenital heart defect -- the risk increases from eight in 1000 to 16 in 1000.

What Types of Congenital Heart Disease Are There?

The most common congenital heart problems include:

  • Heart valve defects. Narrowing or stenosis of the valves or complete closure that impedes or prevents forward blood flow. Other valve defects include leaky valves that don't close properly and allow blood to leak backwards.
  • Defects in the walls between the atria and ventricles of the heart (atrial and ventricular septal defects). These defects allow abnormal mixing of oxygenated and unoxygenated blood between the right and left sides of the heart.
  • Heart muscle abnormalities that can lead to heart failure.

What Are the Symptoms of Congenital Heart Disease in Adults?

Congenital heart defects may be diagnosed before birth, right after birth, during childhood or not until adulthood. It is possible to have a defect and no symptoms at all. In adults, if symptoms are present, they may include:

  • Shortness of breath.
  • Limited ability to exercise.

How Is Congenital Heart Disease Diagnosed?

Congenital heart disease is often first detected when your doctor hears an abnormal heart sound or heart murmur when listening to your heart.

Depending on the type of murmur your doctor hears, he or she may order further testing such as:

  • Echocardiogram or transesophageal echocardiogram (TEE)
  • Intravascular ultrasound (IVUS)
  • Cardiac catheterization
  • Chest X-ray
  • Electrocardiogram (ECG or EKG)
  • MRI
  • Positron emission tomography (PET) scan

How Is Congenital Heart Disease Treated?

Treatment is based on the severity of the disease. Some mild heart defects do not require any treatment. Others can be treated with medications, procedures or surgery. Most adults with congenital heart disease should be monitored by a heart specialist and take precautions to prevent endocarditis (a serious infection of the heart valves) throughout their life.

How Can I Prevent Endocarditis?

Those with congenital heart disease are at risk for getting endocarditis, even if the heart was repaired or replaced through surgery. To protect yourself:

  • Tell all doctors and dentists you have congenital heart disease. You may want to carry a card with this information.
  • Call your doctor if you have symptoms of an infection (sore throat, general body aches, fever).
  • Take good care of your teeth and gums to prevent infections. See your dentist for regular visits.
  • Take antibiotics according to the American Heart Association guidelines before you undergo any procedure that may cause bleeding, such as: any dental work (even a basic teeth cleaning), invasive tests (any test that may involve blood or bleeding), and most major or minor surgery. Check with your doctor about the type and amount of antibiotics that you should take.

Congenital Heart Disease in Children

There are several congenital heart defects that are detected and treated early in infancy. Most of them are abnormal connections among the veins, and arteries of the heart, and arteries ( such as the aortic and pulmonary arteries). These abnormal connections can allow unoxygenated blood to flow to the body instead of to the lungs, or allow oxygenated blood to flow to the lungs instead of to the body. They may also cause heart failure. Some examples of congenital heart disease in infants and children include:

  • Patent ductus arteriosus (when blood bypasses the lungs preventing oxygen to circulate throughout the body).
  • Tetralogy of Fallot (four different heart defects that occur together).
  • Transposition of the great vessels (blood from the left side of the heart and right side of the heart intermix because the large artery connections are incorrect).
  • Coarctation of the aorta (a pinched aorta).
  • Heart valve problems.

What Are the Symptoms of Congenital Heart Disease in Infants and Children?

The symptoms of congenital heart disease in infants and children include:

  • Cyanosis (a bluish tint to the skin, fingernails and lips).
  • Fast breathing and poor feeding.
  • Poor weight gain.
  • Recurrent lung infections.
  • Inability to exercise.

How Is Congenital Heart Disease in Children Treated?

Most defects will require surgery or an interventional procedure to repair the problem. Often children with congenital heart disease will also need treatment with medication to improve heart function as well.

Children and adults with congenital heart disease should be treated by a cardiologist who specializes in congenital heart disease. Some types of disease may require a team approach as the child grows into an adult.

Thursday, August 28, 2008

Atrial fibrillation

Atrial fibrillation is increasingly common with advancing age. During atrial fibrillation, the heart's two upper chambers (the atria) beat chaotically and irregularly — out of coordination with the two lower chambers (the ventricles) of the heart. The result is an irregular and often rapid heart rate that causes poor blood flow to the body and symptoms of heart palpitations, shortness of breath and weakness. Most people with atrial fibrillation have an increased risk of developing blood clots that may lead to stroke.

Atrial fibrillation is a common heart rhythm problem. More than 2 million Americans have atrial fibrillation, which can cause palpitations, shortness of breath, fatigue and stroke.

Atrial fibrillation is often caused by changes in your heart that occur as a result of heart disease or high blood pressure. Episodes of atrial fibrillation can come and go, or you may have chronic atrial fibrillation.

Although atrial fibrillation usually isn't life-threatening, it can lead to complications. Treatments for atrial fibrillation may include medications and other interventions to try to alter the heart's electrical system.

Symptoms

A heart in atrial fibrillation doesn't beat efficiently. It may not be able to pump an adequate amount of blood out to your body with each heartbeat, causing a drop in your blood pressure.

Some people with atrial fibrillation have no symptoms and are unaware of their condition until their doctor discovers it during a physical examination. Those who do have symptoms may experience:

  • Palpitations, which are sensations of a racing, uncomfortable, irregular heartbeat or a flopping in your chest
  • Weakness
  • Lightheadedness
  • Confusion
  • Shortness of breath
  • Chest pain

Atrial fibrillation may be:

  • Sporadic. In this case it's called paroxysmal (par-ok-SIZ-mul) atrial fibrillation. You may have symptoms that come and go, lasting for a few minutes to hours and then stopping on their own.
  • Chronic. With chronic atrial fibrillation, symptoms may last until they're treated.
Causes

To pump blood, your heart muscles must contract and relax in a coordinated rhythm. Contraction and relaxation are controlled by electrical signals that travel through your heart muscles.

Your heart consists of four chambers — two upper chambers (atria) and two lower chambers (ventricles). Within the upper right chamber of your heart (right atrium) is a group of cells called the sinus node. This is your heart's natural pacemaker. The sinus node produces the impulse that starts each heartbeat.

Normally, the impulse travels first through the atria, then through a connecting pathway between the upper and lower chambers of your heart called the atrioventricular (AV) node. As the signal passes through the atria, they contract, pumping blood from your atria into the ventricles below. A split second later, as the signal passes through the AV node through the right and left bundle branches to the ventricles, the ventricles contract, pumping blood out to your body.

In atrial fibrillation, the upper chambers of your heart (atria) experience chaotic electrical signals. As a result, they quiver. The AV node — the electrical connection between the atria and the ventricles — is overloaded with impulses trying to get through to the ventricles. The ventricles also beat rapidly, but not as rapidly as the atria. The reason is because the AV node is like a highway on-ramp — only so many cars can get on at one time. The result is an irregular and fast heart rhythm. The heart rate in atrial fibrillation may range from 100 to 175 beats a minute. The normal range for a heart rate is 60 to 100 beats a minute.

Possible causes
Abnormalities or damage to the heart's structure is the most common cause of atrial fibrillation. Diseases affecting the heart's valves or pumping system are common causes, as is long-term high blood pressure. However, some people who have atrial fibrillation don't have underlying structural heart disease, a condition called lone atrial fibrillation. In lone atrial fibrillation, the cause is often unclear. Serious complications are usually rare in lone atrial fibrillation.

Possible causes of atrial fibrillation include:

  • High blood pressure
  • Heart attacks
  • Abnormal heart valves
  • Congenital heart defects
  • An overactive thyroid or other metabolic imbalance
  • Exposure to stimulants, such as medications, caffeine or tobacco, or to alcohol
  • Sick sinus syndrome — this occurs when the heart's natural pacemaker stops functioning properly
  • Emphysema or other lung diseases
  • Previous heart surgery
  • Viral infections
  • Stress due to pneumonia, surgery or other illnesses
  • Sleep apnea

Risk factors

  • Age. The older you are, the greater your risk of developing atrial fibrillation. As you age, the electrical and structural properties of the atria can change. This may lead to the breakdown of the normal atrial rhythm.
  • Heart disease. Anyone with heart disease, including valve problems, history of heart attack and heart surgery, faces an increased risk of atrial fibrillation.
  • Other chronic conditions. People with thyroid problems, high blood pressure, sleep apnea and other medical problems have an elevated risk of atrial fibrillation.
  • Alcohol use. Use of alcohol, especially binge drinking, can trigger an episode of atrial fibrillation.
  • Family history. An increased risk of atrial fibrillation runs in some families. In some of these cases, specific genes have been identified as the likely cause of atrial fibrillation.

Tests and diagnosis

To make a diagnosis of atrial fibrillation, your doctor may do tests that involve the following:

  • Electrocardiogram (ECG). Patches with wires (electrodes) are attached to your skin to measure electrical impulses given off by your heart. Impulses are recorded as waves displayed on a monitor or printed on paper.
  • Holter monitor. This is a portable machine that records all of your heartbeats. You wear the monitor under your clothing. It records information about the electrical activity of your heart as you go about your normal activities for a day or two. You can press a button if you feel symptoms, and then your doctor can figure out what heart rhythm was present at that moment.
  • Event recorder. This device is similar to a Holter monitor except all of your heartbeats are not recorded. There are two recorder types: One uses a phone to transmit signals from the recorder while you're experiencing symptoms. The other type is worn all the time (except while showering) for as long as a month. Event recorders are especially useful in diagnosing rhythm disturbances that occur at unpredictable times.
  • Echocardiogram. In this test, sound waves are used to produce a video image of your heart. Sound waves are directed at your heart from a wand-like device (transducer) that's held on your chest. The sound waves that bounce off your heart are reflected back through your chest wall and processed electronically to provide video images of your heart in motion to detect underlying structural heart disease.
  • Blood tests. These help your doctor rule out thyroid problems or blood chemistry abnormalities that may lead to atrial fibrillation.

Complications

Sometimes, atrial fibrillation can lead to the following complications:

  • Stroke. In atrial fibrillation, the chaotic rhythm may cause blood to pool in your atria and form clots. If a blood clot forms, it could dislodge from your heart and travel to your brain. There it might block arterial blood flow, causing a stroke. The risk of stroke in atrial fibrillation depends on your age (you have a higher risk as you age) and on whether you have high blood pressure or a history of heart failure or previous stroke, and other factors. Most people with atrial fibrillation have a much greater risk of stroke than do those who don't have atrial fibrillation. Medications such as blood thinners can greatly lower your risk of stroke or damage to other organs caused by blood clots.
  • Heart failure. Atrial fibrillation alone, especially if not controlled, may weaken the heart, leading to heart failure — a condition in which your heart can't circulate enough blood to meet your body's needs.

Treatments and drugs

Treatments for atrial fibrillation include medications and procedures that attempt to either reset the heart rhythm back to normal or control the heart rate so that the heart doesn't beat dangerously fast, though it may still beat irregularly. Treatments also include blood thinners to prevent blood clots.

The treatment option best for you will depend on how long you've had atrial fibrillation, how bothersome your symptoms are and the underlying cause of your atrial fibrillation. Generally, the goals of treating atrial fibrillation are to:

  • Reset the rhythm — or — control the rate
  • Prevent blood clots

Sometimes atrial fibrillation will correct or "reset" itself. In some people, a specific event or an underlying condition, such as a thyroid disorder, may trigger atrial fibrillation. If the condition that triggered your atrial fibrillation can be treated, you might not have any more heart rhythm problems — or at least not for quite some time. If your symptoms are bothersome or if this is your first episode of atrial fibrillation, your doctor may attempt to reset the rhythm. Or it may be best to simply take medications to control the heart rate and prevent blood clots.

The best strategy for you depends on many factors, including whether you have other problems with your heart and how well you tolerate the medications available to treat atrial fibrillation or control the rate. In some cases, you may need a more invasive treatment, such as catheter or surgical techniques.

Resetting the rhythm
Ideally, to treat atrial fibrillation, the heart rate and rhythm are reset to normal. This can be accomplished in some cases, depending on the underlying cause of atrial fibrillation and how long you've had it. To correct atrial fibrillation, doctors may be able to reset your heart to its regular rhythm (sinus rhythm) using a procedure called cardioversion. Cardioversion can be done in two ways:

  • Cardioversion with drugs. This form of cardioversion uses medications called anti-arrhythmics to help restore normal sinus rhythm. Depending on your heart condition, your doctor may recommend trying intravenous or oral medications to return your heart to normal rhythm. This is often done in the hospital with continuous monitoring of your heart rate. If your heart rhythm returns to normal, your doctor often will prescribe the same anti-arrhythmic or a similar one long term to try to prevent recurrent spells of atrial fibrillation.
  • Electrical cardioversion. In this brief procedure, an electrical shock is delivered to your heart through paddles or patches placed on your chest. The shock stops your heart's electrical activity for a split second. When your heart begins again, the hope is that it resumes its normal rhythm. The procedure is performed under anesthesia.

Before undergoing cardioversion, you may be given a blood-thinning medication, such as warfarin (Coumadin), for several weeks to reduce the risk of blood clots and stroke. Alternatively, you may undergo transesophageal echocardiography — a test to exclude the presence of a blood clot — just before cardioversion. In transesophageal echocardiography, a tube is passed down your esophagus and detailed ultrasound images are made of your heart. Unless the episode of atrial fibrillation lasted less than 24 hours, you will require warfarin for at least four to six weeks after cardioversion to prevent a blood clot from forming even after your heart is back in normal rhythm.

Maintaining normal rhythm
After electrical cardioversion, anti-arrhythmics often are prescribed to help prevent future episodes of atrial fibrillation. Commonly used medications include amiodarone (Cordarone, Pacerone), propafenone (Rythmol), procainamide (Procanbid) and dofetilide (Tikosyn). Although these drugs can help maintain sinus rhythm in many people, they can cause side effects, such as nausea, dizziness and fatigue. In rare instances, they may cause ventricular arrhythmias — life-threatening rhythm disturbances originating in the heart's lower chambers. These medications may be needed indefinitely. Unfortunately, even with medications, the chance of another episode of atrial fibrillation is high.

Rate control
Sometimes atrial fibrillation can't be converted back to a normal heart rhythm. Then the goal is to slow the heart rate (rate control). Traditionally, doctors have prescribed the medication digoxin (Lanoxin). It can control heart rate at rest but not as well during activity. Most people require additional or alternative medications, such as calcium channel blockers or beta blockers. In general, your heart rate should be between 60 and 100 beats a minute when you're at rest. Your doctor can give you guidelines for your maximal heart rate.

Some people may not be able to tolerate medications, or medications don't work to control the heart rate. In these cases, AV node ablationmay be an option.

AV node ablation involves applying radio frequency energy to your atrioventricular (AV) node through a long, thin tube (catheter) to destroy this small area of tissue. The procedure prevents the atria from sending electrical impulses to the ventricles. The atria continue to fibrillate, though, and anticoagulant medication is still required. A pacemaker is then implanted to establish a normal rhythm.After AV node ablation, you'll need to continue to take anticoagulant medications to reduce the risk of stroke because your heart is still in atrial fibrillation.

Surgical and catheter interventions
Sometimes medications or cardioversion to control atrial fibrillation doesn't work. In those cases, your doctor may recommend a procedure to destroy the area of heart tissue responsible for the erratic electrical signals and restore your heart to a normal rhythm. These options can include:

  • Radiofrequency catheter ablation. In many people who have atrial fibrillation and an otherwise normal heart, atrial fibrillation is caused by rapidly discharging triggers, or "hot spots." These hot spots are like abnormal pacemaker cells that fire so rapidly that the atria fibrillate. When present, these triggers are most commonly found in the pulmonary veins, the veins that return blood from the lungs to the heart. Radio frequency energy directed to these hot spots through a catheter (called radiofrequency ablation, pulmonary vein ablation or pulmonary vein isolation) may be used to destroy these hot spots, scarring the tissue and thereby disrupting the erratic electrical signals. This eliminates the arrhythmia without the need for medications or implantable devices. In some cases, additional spots are treated in your heart — depending on the electrical circuits found — and sometimes other types of catheters that can freeze the heart tissue (cryotherapy) are used.
  • Surgical maze procedure. The maze procedure is often done during an open-heart surgery. Using a scalpel, doctors create several precise incisions in the atria to create a pattern or maze of scar tissue. Because scar tissue doesn't carry electricity, it interferes with stray electrical impulses that cause atrial fibrillation. Radio frequency or cryotherapy can also be used, and there are several variations of the surgical maze technique. The procedure has a high success rate, but because it usually requires open-heart surgery, it's generally reserved for people who don't respond to other treatments or when it can be done during other necessary heart surgery, such as coronary artery bypass surgery or heart valve repair. Some people require a pacemaker after the procedure.

    Newer and less invasive techniques are being developed to create the atrial scar tissue. Doctors at some centers use radio frequency or cryotherapy applied to the outside surface of the heart through a small chest incision or through a scope placed into the chest cavity (thorascopic approach). Microwave, laser and ultrasound energy are also being studied as options to perform the maze procedure.

Preventing blood clots
Most people who have atrial fibrillation or who are undergoing certain treatment for atrial fibrillation are at especially high risk of blood clots that can lead to stroke. The risk is even higher if other heart disease is present along with atrial fibrillation. Your doctor may prescribe blood-thinning medications (anticoagulants), such as warfarin (Coumadin) or aspirin, in addition to medications designed to treat your irregular heartbeat. Many people have spells of atrial fibrillation and don't even know it — so you may need lifelong anticoagulants even after your rhythm has been restored to normal.

Atrial flutter
Atrial flutter is similar to atrial fibrillation, but slower. If you have atrial flutter, the abnormal heart rhythm in your atria is more organized and less chaotic than in the abnormal patterns common with atrial fibrillation. Sometimes you may have atrial flutter that develops into atrial fibrillation and vice versa. The symptoms, causes and risk factors of atrial flutter are similar to atrial fibrillation. For example, strokes are a common concern in someone with atrial flutter.

One difference between atrial flutter and atrial fibrillation is that many people with atrial flutter respond better to treatment such as catheter ablation. As with atrial fibrillation, atrial flutter is usually not life-threatening when it's properly treated.

Monday, August 25, 2008

Angina Pectoris

Angina, or angina pectoris, is the medical term used to describe the temporary chest discomfort that occurs when the heart is not getting enough blood.

  • The heart is a muscle (myocardium) and gets its blood supply from the coronary arteries.
  • Blood carries the oxygen and nutrients the heart muscle needs to keep pumping.
  • When the heart does not get enough blood, it can no longer function at its full capacity.
  • When physical exertion, strong emotions, extreme temperatures, or eating increase the demand on the heart, a person with angina feels temporary pain, pressure, fullness, or squeezing in the center of the chest or in the neck, shoulder, jaw, upper arm, or upper back. This is angina, especially if the discomfort is relieved by removing the stressor and/or taking sublingual (under the tongue) nitroglycerin.
  • The discomfort of angina is temporary, meaning a few seconds or minutes, not lasting hours or all day.

Causes

Angina is classified as one of the following two types:

  • Stable angina
  • Unstable angina

Stable Angina

Stable angina is the most common angina, and the type most people mean when they refer to angina.

  • People with stable angina usually have angina symptoms on a regular basis. The episodes occur in a pattern and are predictable.
  • For most people, angina symptoms occur after short bursts of exertion.
  • Stable angina symptoms usually last less than five minutes.
  • They are usually relieved by rest or medication, such as nitroglycerin under the tongue.

Unstable Angina

Unstable angina is less common. Angina symptoms are unpredictable and often occur at rest.

  • This may indicate a worsening of stable angina, but sometimes the first time a person has angina it is already unstable.
  • The symptoms are worse in unstable angina - the pains are more frequent, more severe, last longer, occur at rest, and are not relieved by nitroglycerin under the tongue.
  • Unstable angina is not the same as a heart attack, but it warrants an immediate visit to the healthcare provider or a hospital emergency department. The patient may need to be hospitalized to prevent a heart attack.

If the patient has stable angina, any of the following may indicate worsening of the condition:

  • An angina episode that is different from the regular pattern
  • Being awakened at night by angina symptoms
  • More severe symptoms than usual
  • Having angina symptoms more often than usual
  • Angina symptoms lasting longer than usual

Symptoms

Angina itself is a symptom (or set of symptoms), not a disease. Any of the following may signal angina:

  • An uncomfortable pressure, fullness, squeezing, or pain in the center of the chest
  • It may also feel like tightness, burning, or a heavy weight.
  • The pain may spread to the shoulders, neck, or arms.
  • It may be located in the upper abdomen, back, or jaw.
  • The pain may be of any intensity from mild to severe.

Other symptoms may occur with an angina attack, as follows:

  • Shortness of breath
  • Lightheadedness
  • Fainting
  • Anxiety or nervousness
  • Sweating or cold, sweaty skin
  • Nausea
  • Rapid or irregular heart beat
  • Pallor (pale skin)
  • Feeling of impending doom

Self-Care at Home

Stop doing whatever it is that causes the symptoms and call 911. Immediate help and intervention is the best chance for survival if someone is having a heart attack or other serious problem.

  • Lie down in a comfortable position with the head up.
  • Chew a regular adult aspirin or its equivalent (as long as the patient is not allergic to aspirin). Chewing more than one will not do any good and may cause unwanted side effects.

If the patient has had angina before and been evaluated by a healthcare provider, follow his or her recommendations.

  • This may mean rest and the immediate use of sublingual nitroglycerin.
  • It may include a visit to the hospital emergency department.

Medical Treatment

If the patient has come to the hospital emergency department, they may be sent to another care area for further testing, treatment, or observation. On the basis of the provider's preliminary diagnosis, the patient may be sent to the following units:

  • An observation unit pending test results or further testing
  • A cardiac care unit
  • A cardiac catheterization unit

Regardless of where the patient is sent, several basic treatments may be started. Which ones are given depends on the severity of the symptoms and the underlying disease.

  • At least one IV line will be started. This line is used to give medication or fluids.
  • Aspirin will probably be administered (unless the patient has already taken one)
  • Oxygen will be administered through a face mask or a tube in the nose. This will help if the patient is having trouble breathing or feeling uncomfortably short of breath. The direct administration of oxygen raises the oxygen content of the blood.

Treatment will depend on the severity of the symptoms, severity of the underlying disease, and extent of damage to the heart muscle, if any.

  • Simple rest and observation, an aspirin, breathing oxygen, and sublingual nitroglycerin may be all that the patient needs, if it is only angina.
  • Medication may be administered to reduce anxiety.
  • Medication may be administered to lower blood pressure or heart rate.
  • Medication may be administered to reduce the risk of having a blood clot or to prevent further clotting.
  • If the healthcare provider believes the chest pain actually represents a heart attack, the patient may be given a fibrinolytic (apowerful clot-buster medication).

After reviewing the patient's immediate test results, the hospital healthcare provider will make a decision about where the patient should be for the next hours and days.

  • If the diagnosis of angina is made, and the patient is feeling better and their condition is stable they may be allowed to go home. The patient may be given medications to take. Follow-up with a primary healthcare provider within the next day or two will be recommended.
  • The patient will be admitted o the hospital if the they are unstable with continuing symptoms. Further testing will be ordered, and if the arteries are critically blocked, the patient may undergo coronary angiography, coronary artery angioplasty, or even coronary artery bypass surgery.

Angioplasty is a treatment used for people whose angina does not get better with medication and/or who are at high risk of having a heart attack.

  • Before angioplasty can be done, the area(s) of coronary artery narrowing is located with coronary arteriography.
  • A thin plastic tube called a catheter is inserted into an artery in the arm or groin with local sedation. The catheter has a tiny balloon attached to the end.
  • The catheter is threaded through the arteries and into the artery where the narrowing is.
  • The balloon on the catheter is inflated, opening up the narrowing.
  • Following ballon treatment, many patients require placement of a "stent," a small metal sleeve that is placed in the narrowed artery. The stent holds the artery open.

Medications

Nitroglycerin: Nitroglycerin is a sublingual (under the tongue) medication relieves angina symptoms by expanding blood vessels and decreasing the muscle's need for oxygen. This allows more blood to flow through the coronary arteries. Nitroglycerin is taken only when the patient actually has symptoms or expect to have them. Slow - or long-acting nitroglycerin can be used as a preventative treatment for angina but not until beta blockers are tried first.

Beta blockers: Beta blockers lessen the heart's workload. They slow the heart rate, decrease blood pressure, and lessen the force of contraction of the heart muscle. This decreases the heart's need for oxygen and thus decreases angina symptoms. Beta blockers are taken every day, regardless of whether the patient is having symptoms, because they are proven to prevent heart attacks and sudden death.

Calcium channel blockers (CCBs): Calcium channel blockers are used primarily when beta blockers cannot be used and/or the patient is still having angina with beta blockers. Calcium channel blockers also lower blood pressure and certain ones slow heart rate. Calcium channel blockers have to be taken every day.

Aspirin: Daily aspirin therapy is mandatory to decrease the possibility of sticky platelets in the blood starting a blood clot.

Statins: Statins lower cholesterol and have been shown to stabilize the fatty plaque on the inner lining of the coronary artery, even when the blood cholesterol is normal or minimally increased. Low density lipoprotein (LDL) or "bad cholesterol" levels should be less than 70 mg/dL for those at high risk of heart disease. Every person with angina needs to know exactly what his or her blood lipids/fats are.

Miscellaneous anti-anginal drugs: New drugs are being studied to treat angina. In 2006, the FDA approved ranolazine (Ranexa). Because of its side effects (potential to cause abnormal heart rhythm), ranolazine is indicated only after other conventional drug treatments are found to be ineffective.

Surgery

Like angioplasty, surgery is an option for people whose angina does not improve with medications and others who are at high risk of having a heart attack. Surgery is usually reserved for people with very severe narrowing or blockage in several coronary arteries.

In almost all cases, the operation used for severely narrowed coronary arteries is coronary artery bypass grafting.

Coronary Artery Bypass Surgery

  • The chest and rib cage are opened up (open heart surgery)

  • The narrowed part of the artery is bypassed by a piece of vein removed from the leg, or with a piece of artery behind the sternum (internal mammary artery), or a portion of the radial artery taken from the lower arm or forearm.
  • Several arteries can be bypassed in one operation.
  • This is a very safe operation, with a mortality rate of less than 1%, in people whose heart muscle is not severely damaged irreversibly and who have normal lungs, kidneys, liver, and other organs.
  • Because the chest is opened, the recovery time can be quite long, especially if the patient is older and has multiple other health problems.

Transmyocardial Revascularization

Transmyocardial revascularization is a procedure for people who cannot undergo angioplasty or surgery.

  • A simple incision is made in the chest, and a laser is used to "drill" small holes through the outside wall of the heart into the left ventricle.
  • About 20-40 holes are made.
  • Bleeding from these holes is minimal and usually stops after a few minutes of pressure.
  • It is not clear why this helps relieve angina. One theory is that it stimulates growth of new blood vessels that improve blood flow to the heart. Other investigators believe it is a placebo effect.

Current research is focusing on trying to find growth factors that could be injected into coronary arteries or directly into the left ventricle to encourage growth of new blood vessels.

Prevention

The best action is to reduce risk factors early in life. The goal is to not have angina, a heart attack, or sudden death in the first place. Although no one can escape aging, inherited risk, or gender, certain risk factors are in your control.

  • Stop smoking and using nicotine in any form.
  • Control high blood pressure.
  • Lower blood fats (through diet, exercise, and medications).
  • Maintain a healthy weight.
  • Control diabetes and blood sugar
  • Do not use stimulants such as cocaine or amphetamines.

If a person already has atherosclerosis and angina, they can learn to take precautions to avoid having symptoms. Avoiding the "triggers" will help keep the person comfortable and free of symptoms.

  • Quit smoking

  • Do not use caffeine, cocaine, amphetamines, or other stimulants
  • Drink alcohol moderately (no more than 1-2 drinks daily)
  • Avoid large and heavy meals that leave you feeling "stuffed"
  • Decrease stress
  • Establish a regular exercise routine (discuss the plan with your healthcare provider)

The question of exercise for a person with angina is important. Exercise is recommended.

  • If the patient has been exercising strenuously, they may need to cut back to avoid symptoms.
  • If the patient has not been exercising, or has been exercising moderately, talk to a healthcare provider first about physical activity that will be safe and comfortable. Sometimes a structured cardiac rehabilitation program is a beneficial way to begin an exercise program.

The healthcare provider may recommend taking an aspirin daily.

  • Aspirin has been shown to reduce the risk of a second heart attack in people who have already had one, and may reduce the risk of a first heart attack.
  • Taking aspirin is not without risks, especially in elderly people, people with digestive diseases or blood clotting disorders, and people who take certain types of medications.
  • Allergy to aspirin is not uncommon. Tell your healthcare provider if you are allergic to aspirin or have a reaction to aspirin.

Friday, August 22, 2008

Pericarditis

Pericarditis is a swelling and irritation of the pericardium, the thin sac-like membrane that surrounds your heart. Pericarditis often causes chest pain and sometimes other symptoms. Pericarditis may be acute or chronic. The sharp chest pain associated with acute pericarditis occurs when the pericardium rubs against the heart's outer layer.

Mild cases may improve on their own. Treatment for more-severe cases may include medications and, rarely, surgery. Early diagnosis and treatment may help to reduce the risk of long-term complications.

Symptoms

If you have acute pericarditis, the most common symptom is sharp, stabbing chest pain behind the breastbone or in the left side of your chest. However, some people with acute pericarditis describe their chest pain as dull, achy or pressure-like instead, and of varying intensity. The sharp pain may travel into your left shoulder and neck. It often intensifies when you lie down or inhale deeply. Sitting up and leaning forward can often ease the pain. At times, it may be difficult to distinguish pericardial pain from the pain that occurs with a heart attack.

Other signs and symptoms often associated with pericarditis include:

  • Shortness of breath when reclining
  • Low-grade fever
  • An overall sense of weakness, fatigue or feeling sick
  • Dry cough
  • Abdominal or leg swelling

Causes

Under normal circumstances, the two-layered pericardial sac that surrounds your heart contains a small amount of lubricating fluid. In pericarditis the sac becomes inflamed and the resulting friction from the inflamed sac rubbing against the outer layer of your heart leads to chest pain.

In some cases the amount of fluid contained in the pericardial sac may increase, causing what is called pericardial effusion.

The cause of pericarditis is often hard to determine. In most cases doctors are either unable to determine a cause (idiopathic) or suspect a viral infection.

Pericarditis can also develop shortly after a major heart attack due to the irritation of the underlying damaged heart muscle. In addition, a delayed form of pericarditis may occur weeks after a heart attack or heart surgery because of antibody formation. This delayed pericarditis is known as Dressler's syndrome. Many experts believe Dressler's syndrome is due to an autoimmune response, a mistaken inflammatory response by the body to its own tissues — in this case, the heart and pericardium.

Other causes of pericarditis include:

  • Systemic inflammatory disorders. These may include lupus and rheumatoid arthritis.
  • Trauma. Injury to your heart or chest may occur as a result of a motor vehicle or other accident.
  • Other health disorders. These may include kidney failure, AIDS, tuberculosis and cancer.
  • Certain medications. Some medications can cause pericarditis, although this is unusual.

When to seek medical advice

Seek immediate medical care if you develop chest pain.

Many of the symptoms of pericarditis are similar to those of other heart and lung conditions. The sooner you are evaluated, the sooner you can receive proper diagnosis and treatment. For example, although the cause of acute chest pain may be pericarditis, the cause could also be a heart attack or a blood clot of the lungs (pulmonary embolus).

Tests and diagnosis

Your doctor will likely begin by taking your medical history and asking questions about your chest pain and other symptoms.

  • Medical history and physical examination. Your doctor may ask whether you've recently experienced an upper respiratory infection or a flu-like sickness, and whether the chest pain worsens when you lie down or when you take a breath.
  • Physical exam. You may also undergo a physical examination and a review of whether you have or have had medical conditions, such as kidney disease, a recent heart attack or chest trauma.
  • Heart sounds. Your doctor may place a stethoscope on your chest to listen for the sounds characteristic of pericarditis, which are made when the pericardium rubs against the outer layer of your heart. Some doctors describe this characteristic noise as pericardial rub.

Your doctor may have you undergo tests that can help determine whether you've had a heart attack, whether fluid has collected in the pericardial sac, or whether there are signs of inflammation. Your doctor may use blood tests to determine if a bacterial or other type of infection is present. You may also undergo one or more of the following diagnostic procedures:

  • Electrocardiogram (ECG). In this test, patches with wires (electrodes) are attached to your skin to measure the electrical impulses given off by your heart. Impulses are recorded as waves displayed on a monitor or printed on paper. Certain ECG results may indicate pericarditis.
  • Chest X-ray. With an X-ray of your chest, your doctor can study the size and shape of your heart. Images of your heart may show an enlarged heart if excess fluid has accumulated in the pericardium.
  • Echocardiogram. This test uses high-frequency sound waves to create a picture of your heart and its structures, including fluid accumulation in the pericardium. Your doctor can view and analyze this image on a monitor.
  • Computerized tomography (CT). This X-ray technique can produce more-detailed images of your heart and the pericardium than would conventional X-ray studies. CT scanning may also be performed to exclude other causes of acute chest pain, such as blood clots in your lung arteries (pulmonary emboli) or a tear in your aorta (aortic dissection).
  • Magnetic resonance imaging (MRI). This technique uses a magnetic field and radio waves to create cross-sectional images of your heart that can reveal thickening or other changes in the pericardium.

Complications

Complications may include:

  • Constrictive pericarditis. Some people with pericarditis, particularly those with long-term inflammation and chronic recurrences, can develop permanent thickening, scarring and contracture of the pericardium. In these people, the pericardium loses much of its elasticity and resembles a rigid case that's tight around the heart, which keeps the heart from working properly. This condition is called constrictive pericarditis and often leads to severe swelling of the legs and abdomen, as well as shortness of breath.
  • Cardiac tamponade. When too much fluid collects in the pericardium, a condition called cardiac tamponade can develop. Excess fluid puts pressure on the heart and doesn't allow it to fill properly. That means less blood leaves the heart, which causes a dramatic drop in blood pressure. If left untreated, cardiac tamponade can be fatal.

Early diagnosis and treatment of pericarditis usually reduces the risk of the long-term complications.

Treatments and drugs

Deciding upon treatment for pericarditis will likely involve consideration of the underlying cause as well as the severity. Mild cases of pericarditis may get better on their own without treatment.

Rest and medications
Your doctor may recommend bed rest until you're feeling better. Medications to reduce the inflammation and swelling associated with pericarditis are often prescribed. Most pain associated with pericarditis responds well to treatment with aspirin or another nonsteroidal anti-inflammatory drug (NSAID). If your pain is severe, you might need stronger pain medications, such as a narcotic, for a short time.

Acute episodes of pericarditis typically last from one to three weeks, but future episodes can occur. About one in five people with pericarditis has a recurrence within months of the original episode. People who have repeated episodes of pericarditis are often treated with a drug called colchicine, and sometimes steroid medications are used.

When a bacterial infection is the underlying cause of pericarditis, you'll be treated with antibiotics and drainage if necessary.

Hospitalization and procedures
You'll likely need hospitalization if your doctor suspects cardiac tamponade, a potentially dangerous complication of pericarditis. When cardiac tamponade is present, you may undergo a technique called pericardiocentesis. In some cases of severe pericarditis, your doctor might suggest surgically removing your pericardium (pericardiectomy).

  • Pericardiocentesis. In this procedure, a doctor uses a sterile needle or a small tube (catheter) to remove and drain the excess fluid from the pericardial cavity. You'll receive a local anesthetic before undergoing pericardiocentesis, which is often done with echocardiogram monitoring and ultrasound guidance. This drainage may continue for several days during the course of your hospitalization.
  • Pericardiectomy. If you're diagnosed with constrictive pericarditis, you may need to undergo a surgical procedure (pericardiectomy) to remove the entire pericardium that has become rigid and is compromising the functioning of your heart.
Source:
http://www.mayoclinic.com/print/pericarditis/DS00505/DSECTION=all&METHOD=print

Thursday, August 21, 2008

Silent Ischemia and Ischemic Heart Disease

What is ischemia?

Ischemia (is-KE'me-ah) is a condition in which the blood flow (and thus oxygen) is restricted to a part of the body. Cardiac ischemia is the name for lack of blood flow and oxygen to the heart muscle.

What is ischemic heart disease?

It's the term given to heart problems caused by narrowed heart arteries. When arteries are narrowed, less blood and oxygen reaches the heart muscle. This is also called coronary artery disease and coronary heart disease. This can ultimately lead to heart attack.

Ischemia often causes chest pain or discomfort known as angina pectoris (AN'jih-nah or an-JI'nah PEK'tor-is).

What is silent ischemia?

As many as 3 to 4 million Americans may have ischemic episodes without knowing it. These people have ischemia without pain — silent ischemia. They may have a heart attack with no prior warning. People with angina also may have undiagnosed episodes of silent ischemia. In addition, people who have had previous heart attacks or those with diabetes are especially at risk for developing silent ischemia.

Having an exercise stress test or wearing a Holter monitor – a battery-operated portable tape recording that measures and records your electrocardiogram (e-lek"tro-KAR'de-o-gram [ECG]) continuously, usually for 24-48 hours – are two tests often used to diagnose this problem. Other tests also may be used.

Source:
http://www.americanheart.org/presenter.jhtml?identifier=4720

Wednesday, August 20, 2008

Left ventricular hypertrophy

Left ventricular hypertrophy is enlargement (hypertrophy) of the muscle tissue that makes up the wall of your heart's main pumping chamber (left ventricle).

Left ventricular hypertrophy develops in response to some factor, such as high blood pressure, that requires the left ventricle to work harder. As the workload increases, the walls of the chamber grow thicker, lose elasticity and eventually may fail to pump with as much force as a healthy heart.

If you have left ventricular hypertrophy, you're at increased risk of heart disease, including heart attack, heart failure, irregular heartbeats (arrhythmia) and sudden cardiac arrest.

The incidence of left ventricular hypertrophy (LVH) increases with age and is more common in people who have high blood pressure or other heart problems.

Symptoms

Left ventricular hypertrophy usually develops gradually. You may experience no signs or symptoms, especially during the early stages of development. When signs or symptoms are present, they may include:

  • Shortness of breath
  • Chest pain
  • Sensation of rapid, fluttering or pounding heartbeats (palpitations)
  • Dizziness
  • Fainting
  • Rapid exhaustion with physical activity
Cause

Left ventricular hypertrophy occurs as a result of one or more things making your heart work harder than normal to pump blood to your body. For example, if you have high blood pressure, the muscles of the left ventricle must contract more forcefully than normal in order to counter the effect of the elevated blood pressure.

The effect of the stronger contraction on your heart is similar to the response of other muscles to an increased workload. If you add weight to a dumbbell for arm curls, your biceps become larger. Similarly, the work of adapting to high blood pressure may result in larger muscle tissue in the walls of the left ventricle. Unlike weight training, however, the increased workload on the heart is constant with each heartbeat and with little time for the heart muscles to relax. The increase in muscle mass causes the heart to function poorly.

Factors that can cause your heart to work harder include the following:

  • High blood pressure (hypertension) is the most common cause of left ventricular hypertrophy. A blood pressure reading is given in a unit of measure called millimeters of mercury (mm Hg). Hypertension is generally defined as systolic pressure greater than 140 mm Hg and a diastolic pressure greater than 90 mm Hg, or 140/90 mm Hg. Systolic pressure is blood pressure while the heart contracts, and diastolic pressure is blood pressure while the heart rests between beats.
  • Aortic valve stenosis is a narrowing of the aortic valve, the flap separating your left ventricle from the aorta, the large blood vessel that delivers oxygen-rich blood to your body. This partial obstruction of blood flow requires the left ventricle to work harder to pump blood into the aorta.
  • Aortic valve regurgitation is a condition in which the heart valve separating the left ventricle and the aorta doesn't close properly, resulting in some blood flowing backward into the left ventricle. This condition increases the volume of blood in the left ventricle and requires more force to pump it out.
  • Dilated cardiomyopathy is enlargement of the left ventricle and, in some cases, other chambers of the heart. Because the space inside the left ventricle is large, it fills with more blood and requires the muscle to contract more forcefully when pumping the blood out.
  • A heart attack usually causes the loss or scarring of muscle tissue. To compensate for this loss, the surviving muscles may need to pump harder.

Risk factors

Risk factors for left ventricular hypertrophy include the following:

  • High blood pressure, a blood pressure reading greater than 140/90 mm Hg, is the greatest risk factor.
  • Aortic stenosis, narrowing of the main valve through which blood leaves the heart, may increase the left ventricle's work load.
  • Obesity can cause high blood pressure and increase your body's demand for oxygen — factors that require the left ventricle to work harder.
  • Coronary artery disease is the obstruction of arteries that supply blood to your heart muscle. If your heart muscle isn't receiving enough blood, your heart responds by pumping more forcefully.

When to seek medical advice

If you experience shortness of breath, brief chest pain or other symptoms associated with left ventricular hypertrophy, see your doctor. Call 911 or your local emergency number if you feel chest pain that lasts more than a few minutes or have severe difficulty breathing.

If you have high blood pressure or another condition that increases your risk of left ventricular hypertrophy, talk to your doctor about regular appointments to monitor your heart. Even if you feel well, you need to have your blood pressure checked annually, or more often if you smoke, are overweight or have other conditions that increase the risk of high blood pressure.

Tests and diagnosis

If you have signs and symptoms associated with heart disease — such as shortness of breath, chest pain, palpitations or others — your doctor will examine your heart function and choose the best treatment.

If you have high blood pressure, your doctor may order heart-related tests as a part of the ongoing management of the condition.

For some of the exams, your doctor may refer you to a heart specialist (cardiologist). Screening tests for left ventricular hypertrophy include:

  • Electrocardiogram (ECG). An electrocardiogram — also called an ECG or EKG — records electrical signals as they travel through your heart. Your doctor can look for patterns among these signals that indicate abnormal heart function and increased left ventricle muscle tissue.
  • Echocardiogram. An echocardiogram uses sound waves to produce live-action images of the heart. This common test enables your doctor to watch your ventricles squeezing and relaxing and valves opening and closing in rhythm with your heartbeat.

    The echocardiogram is a primary tool for diagnosing left ventricular hypertrophy. If you have left ventricular hypertrophy, your doctor will be able to see thickening of muscle tissue in the left ventricle. An echocardiogram can also reveal how much blood is pumped from the heart with each beat and how stiff the heart muscle is. It may also show related heart abnormalities, such as aortic valve stenosis.

  • Magnetic resonance imaging (MRI). Magnetic resonance imaging is a technique that uses a magnetic field and radio waves to create images of soft tissues in the body. It can be used to produce a thin cross-sectional "slice" of your heart or a three-dimensional image.

Complications

Left ventricular hypertrophy changes both the structure and function of the chamber:

  • The enlarged muscle loses elasticity and stiffens, preventing the chamber from filling properly and leading to increased pressure in the heart.
  • The enlarged muscle tissue compresses its own blood vessels (coronary arteries) and may restrict its own supply of blood.
  • The overworked muscle weakens.

Complications that can occur as a result of these problems include:

  • Inability of your heart to pump enough blood to your body (heart failure)
  • Abnormal heart rhythm (arrhythmia)
  • Insufficient supply of oxygen to the heart (ischemic heart disease)
  • Interruption of blood supply to the heart (heart attack)
  • Sudden, unexpected loss of heart function, breathing and consciousness (sudden cardiac arrest)

Treatments and drugs

Treatment for left ventricular hypertrophy focuses on the underlying cause of the condition. Depending on the cause, treatment may involve medication or surgery.

Treating high blood pressure
Treatment for high blood pressure usually includes both medications and lifestyle changes, such as regular exercise; a low-sodium, low-fat diet; and no smoking.

In addition to lowering blood pressure, some high blood pressure drugs may prevent further enlargement of left ventricle muscle tissue and may even result in shrinking of the hypertrophic muscles. Blood pressure drugs that may reverse muscle growth include the following:

  • Thiazide diuretics act on your kidneys to help your body eliminate sodium and water, thereby reducing blood volume. Thiazide diuretics are often the first — but not the only — choice in high blood pressure medications.
  • Angiotensin-converting enzyme (ACE) inhibitors are a type of drug that widens, or dilates, blood vessels to lower blood pressure, improve blood flow and decrease the workload on the heart. Examples include enalapril (Vasotec), lisinopril (Prinivil, Zestril) and captopril (Capoten).

    ACE inhibitors cause an irritating cough in some people. It may be best to put up with the cough, if you can, to gain the medication's benefits. Discuss this side effect with your doctor. Switching to another ACE inhibitor or an angiotensin II receptor blocker may help.

  • Angiotensin II receptor blockers (ARBs), which include losartan (Cozaar) and valsartan (Diovan), have many of the beneficial effects of ACE inhibitors, but they don't cause a persistent cough. They may be an alternative for people who can't tolerate ACE inhibitors.
  • Beta blockers slow your heart rate, reduce blood pressure and prevent some of the harmful effects of stress hormones. These drugs include carvedilol (Coreg), metoprolol (Toprol XL) and bisoprolol (Zebeta).
  • Calcium channel blockers prevent calcium from entering cells of the heart and blood vessel walls. This lowers blood pressure. These drugs include amlodipine (Norvasc), diltiazem (Cardizem, Dilacor XR), nifedipine (Adalat, Procardia) and verapamil (Calan, Isoptin, Verelan, Covera).

Aortic valve repair or replacement
If left ventricular hypertrophy is caused by aortic valve stenosis, you may have surgery to remove the narrow valve and replace it with either an artificial valve or a tissue valve from a pig, cow or human-cadaver donor. If you have aortic valve regurgitation, the leaky valve may be surgical repaired or replaced.

Prevention

The best way to help prevent left ventricular hypertrophy is to maintain healthy blood pressure. Here are a few tips to better manage your blood pressure:

  • Monitor high blood pressure. If you have high blood pressure, get a home blood pressure measuring device and check your blood pressure frequently. Schedule regular checkups with your doctor. The target for healthy blood pressure is less than 120/80 mm Hg.
  • Make time for exercise. Regular exercise helps lower blood pressure. Aim for 30 minutes of moderate activity at least five times a week. Talk to your doctor about whether you need to restrict certain physical activities, such as weightlifting, which may temporarily raise your blood pressure.
  • Watch your diet. Avoid foods that are high in fat and salt, and increase your consumption of fruits and vegetables. Avoid alcohol and caffeinated beverages, or drink them in moderation.
Source:
http://www.mayoclinic.com/print/left-ventricular-hypertrophy/DS00680/DSECTION=all&METHOD=print

Tuesday, August 19, 2008

Heart Tumors

Tumors of the heart either develop directly in the heart muscle (primary tumors) or spread from another location in the body to the heart (metastatic tumors). The symptoms and complications produced by a heart tumor depend on several factors, including the location and size of the tumor. Heart tumors can be symptomless or can cause life-threatening complications, such as arrhythmias (an abnormal heartbeat), conduction disturbances (electrical disturbances) and heart failure.

Primary tumors of the heart are rare. They include:

Myxomas. The most common type of heart tumor, myxomas are often associated with other abnormalities such as adrenal gland disease and pituitary gland tumors.

Lipomas. These tumors are made up of fat cells. They usually don't cause problems.

Rhabdomyomas and fibromas. These tumors more commonly occur in infants and children. Rhabdomyomas consist of muscle tissue and fibromas consist of fibrous tissue. They usually form in the ventricles and can obstruct blood flow out of the ventricles.

Sarcomas. Sarcomas grow very rapidly and are deadly. Metastatic tumors of the heart are more common than primary tumors. Many different types of cancer can spread to the heart. The most frequent one is malignant melanoma (a type of skin cancer).

Source:
http://www.intelihealth.com/IH/ihtIH/WSIHW000/8059/11162/275183.html?d=dmtContent