CARDIOLOGY

ANATOMY

The heart

The heart weighs between 7 and 15 ounces (200 to 425 grams) and is a little larger than the size of your fist. By the end of a long life, a person's heart may have beat (expanded and contracted) more than 3.5 billion times. In fact, each day, the average heart beats 100,000 times, pumping about 2,000 gallons (7,571 liters) of blood.

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Your heart is located between your lungs in the middle of your chest, behind and slightly to the left of your breastbone (sternum). A double-layered membrane called the pericardium surrounds your heart like a sac. The outer layer of the pericardium surrounds the roots of your heart's major blood vessels and is attached by ligaments to your spinal column, diaphragm, and other parts of your body. The inner layer of the pericardium is attached to the heart muscle. A coating of fluid separates the two layers of membrane, letting the heart move as it beats.

Your heart has 4 chambers. The upper chambers are called the left and right atria, and the lower chambers are called the left and right ventricles. A wall of muscle called the septum separates the left and right atria and the left and right ventricles. The left ventricle is the largest and strongest chamber in your heart. The left ventricle's chamber walls are only about a half-inch thick, but they have enough force to push blood through the aortic valve and into your body.

The Heart Valves

Four valves regulate blood flow through your heart:

The tricuspid valve regulates blood flow between the right atrium and right ventricle.

The pulmonary valve controls blood flow from the right ventricle into the pulmonary arteries, which carry blood to your lungs to pick up oxygen.

The mitral valve lets oxygen-rich blood from your lungs pass from the left atrium into the left ventricle.

The aortic valve opens the way for oxygen-rich blood to pass from the left ventricle into the aorta, your body's largest artery. which carries blood through the body.

 

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The Conduction System

Electrical impulses from your heart muscle (the myocardium) cause your heart to contract. This electrical signal begins in the sinoatrial (SA) node, located at the top of the right atrium. The SA node is sometimes called the heart's "natural pacemaker." An electrical impulse from this natural pacemaker travels through the muscle fibers of the atria and ventricles, causing them to contract. Although the SA node sends electrical impulses at a certain rate, your heart rate may still change depending on physical demands, stress, or hormonal factors.

 

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The Cardiovascular System

The heart and circulatory system make up your cardiovascular system. Your heart works as a pump that pushes blood to the organs, tissues, and cells of your body. Blood delivers oxygen and nutrients to every cell and removes the carbon dioxide and waste products made by those cells. Blood is carried from your heart to the rest of your body through a complex network of arteries, arterioles, and capillaries. Blood is returned to your heart through venules and veins. If all the vessels of this network were laid end to end, they would extend for about 60,000 miles (more than 96,500 kilometers), which is far enough to circle the planet Earth more than twice!

The one-way system carries blood to all parts of your body. This process of blood flow within your body is called circulation. Arteries carry oxygen-rich blood away from your heart, and veins carry oxygen-poor blood back to your heart.

In pulmonary circulation, though, the roles are switched. It is the pulmonary artery that brings oxygen-poor blood into your lungs and the pulmonary vein that brings oxygen-rich blood back to your heart.

In the diagram, the vessels that carry oxygen-rich blood are colored red, and the vessels that carry oxygen-poor blood are colored blue.

Twenty major arteries make a path through your tissues, where they branch into smaller vessels called arterioles. Arterioles further branch into capillaries, the true deliverers of oxygen and nutrients to your cells. Most capillaries are thinner than a hair. In fact, many are so tiny, only one blood cell can move through them at a time. Once the capillaries deliver oxygen and nutrients and pick up carbon dioxide and other waste, they move the blood back through wider vessels called venules. Venules eventually join to form veins, which deliver the blood back to your heart to pick up oxygen.

Vasculature of the Torso

Vasculature of the Head

Vasculature of the Arm

Vasculature of the Leg

Heart disease is an umbrella term for any type of disorder that affects the heart. Heart disease means the same as cardiac diseasebut not cardiovascular disease. Cardiovascular disease refers to disorders of the blood vessels and heart, while heart disease refers to just the heart.
According to WHO (World Health Organization) and the CDC, heart disease is the leading cause of death in the UK, USA, Canada and Australia. The number of US adults diagnosed with heart disease stands at 26.6 million (11.3% of adult population)
23.5% of all deaths in the USA today are caused by heart disease.
We take a look at some of the most common examples of heart disease below.

Angina
Also known as angina pectoris, angina occurs when an area of heart muscle does not get enough oxygen. The patient experiences chest discomfort, tightness or pain. Angina is not technically a disease, but rather a symptom of coronary artery disease. Lack of oxygen to the heart muscle is usually caused by the narrowing of the coronary arteries because of plaque accumulation (atherosclerosis).

Angina - or angina pectoris (Latin for squeezing of the chest) - is chest pain, discomfort, or tightness that occurs when an area of the heart muscle is receiving decreased blood oxygen supply. It is not a disease itself, but rather a symptom of coronary artery disease, the most common type of heart disease.
The lack of oxygen rich blood to the heart is usually a result of narrower coronary arteries due to plaque buildup, a condition called atherosclerosis. Narrow arteries increase the risk of pain, coronary artery disease, heart attack, and death.
Angina may manifest itself in the form of an angina attack, pain or discomfort in the chest that typically lasts from 1 to 15 minutes. The condition is classified by the pattern of attacks into stable, unstable, and variant angina.

• Stable (or chronic) angina is brought on when the heart is working harder than usual, such as during exercise. It has a regular pattern and can be predicted to happen over months or even years. Symptoms are relieved by rest or medication.
• Unstable angina does not follow a regular pattern. It can occur when at rest and is considered less common and more serious as it is not relieved by rest or medicine. This version can signal a future heart attack within a short time - hours or weeks.
• Variant (Prinzmetal's) angina and microvascular (smallest vessels) angina are rare and can occur at rest without any underlying coronary artery disease. This angina is usually due to abnormal narrowing or relaxation (spasm) of the blood vessels, reducing blood flow to the heart. It is relieved by medicine.

Angina risk factors
Those at an increased risk of coronary artery disease are also at an increased risk of angina. Risk factors include:

• Unhealthy cholesterol levels
• Hypertension (high blood pressure)
• Tobacco smoking
• Diabetes
• Being overweight or obese
• Metabolic syndrome
• Sedentary lifestyle
• Being over 45 for men and over 55 for women
• Family history of early heart disease.

Causes of angina

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Angina is most frequently the result of underlying coronary artery disease. The coronary arteries supply the heart with oxygen rich blood. When cholesterol aggregates on the artery wall and hard plaques form, the artery narrows.

It is increasingly difficult for oxygen rich blood to reach the heart muscle as these arteries become too narrow. In addition, damage to the arteries from other factors (such as smoking and high levels of fat or sugar in the blood) can cause plaque to build up where the arteries are damaged. These plaques narrow the arteries or may break off and form blood clots that block the arteries.

The actual angina attacks are the result of this reduced oxygen supply to the heart. Physical exertion is a common trigger for stable angina, as the heart demands more oxygen than it receives in order to work harder. In addition, severe emotional stress, a heavy meal, exposure to extreme temperatures, and smoking may trigger angina attacks.

Unstable angina is often caused by blood clots that partially or totally block an artery. Larger blockages may lead to heart attacks. As blood clots form, dissolve, and form again, angina can occur with each blockage.

Variant angina occurs when an artery experiences a spasm that causes it to tighten and narrow, disrupting blood supply to the heart. This can be triggered by exposure to cold, stress, medicines, smoking, or cocaine use.

Symptoms of angina

Angina is usually felt as a squeezing, pressure, heaviness, tightening, squeezing, burning or aching across the chest, usually starting behind the breastbone. This pain often spreads to the neck, jaw, arms, shoulders, throat, back, or even the teeth.

Patients may also complain of symptoms that include indigestion, heartburn, weakness, sweating, nausea, cramping, and shortness of breath.

Stable angina usually is unsurprising, lasts a short period of time, and may feel like gas or indigestion. Unstable angina occurs at rest, is surprising, last longer, and may worsen over time. Variant angina occurs at rest and is usually severe.

Arrhythmia

Arrhythmia is an irregular heartbeat.

• Tachycardia is when the heart beats too fast
• Bradycardia is when the heart beats too slowly
•  Premature contraction is when the heart beats too early
•  Fibrillation is when the heart beat is irregular

Arrhythmias are problems with heart-rhythm. They happen when the heart's electrical impulses that coordinate heartbeats do not work properly, making the heart beat in a way it should not, either too fast, slowly or erratically.

Irregular heartbeats are common, we all experience them. They feel like a fluttering or a racing heart. However, when they veer too far from normal heartbeat or occur because of a damaged or weak heart, they need to be taken more seriously and treated. Irregular heartbeats can become fatal.

Diagram of the heart. Blue parts indicate de-oxygenated blood pathways while red parts indicate oxygenated pathways

Tachycardia refers to an abnormally fast resting heart rate - usually at least 100 beats per minute.

The threshold of a normal heart rate (pulse) is generally based on the person's age. Tachycardia can be dangerous; depending on how hard the heart has to work.

In general, the adult resting heart beats between 60 and 100 times per minute (some doctors place the healthy limit at 90, so some of them may diagnose tachycardia at slightly lower than 100 beats per minute). When an individual has tachycardia the upper or lower chambers of the heart beat significantly faster - sometimes this happens to both chambers.

When the heart beats too rapidly, it pumps less efficiently and blood flow to the rest of the body, including the heart itself is reduced. The higher-than-normal heartbeat means there is an increase in demand for oxygen by the myocardium (heart muscle) - if this persists it can lead to myocardial infarction (heart attack), caused by the dying off of oxygen-starved myocardial cells.

Some patients with tachycardia may have no symptoms or complications. Tachycardia significantly increases the risk of stroke, sudden cardiac arrest or death.

Our heart rates are controlled by electrical signals which are sent across heart tissues. When the heart produces rapid electrical signals tachycardia occurs.

Causes of tachycardia

Tachycardia is generally caused by a disruption in the normal electrical impulses that control our heart's pumping action rhythm - the rate at which our heart pumps. The following situations, conditions and illnesses are possible causes:

•   A reaction to certain medications
•   Congenital (present at birth) electrical pathway abnormalities in the heart
•   Congenital abnormalities of the heart
•   Consuming too much alcohol
•   Consumption of cocaine and some other recreational drugs
•   Electrolyte imbalance
•   Heart disease which has resulted in poor blood supply and damage to heart tissues, including coronary artery disease (atherosclerosis), heart valve disease, heart failure, heart muscle disease (cardiomyopathy), tumors, or infections.
•   Hypertension
•   Hyperthyroidism (overactive thyroid gland)
•   Smoking
•   Certain lung diseases

Sometimes the medical team may not identify the exact cause of the tachycardia.

Atria, ventricles and the electrical circuitry of the heart

The human heart consists of four chambers:

•   Atria - the two upper chambers; a left atrium and a right atrium.
•   Ventricles - the two lower chambers; a left ventricle and a right ventricle.

The heart has a natural pacemaker called the sinus node; it is located in the right atrium. The sinus code produces electrical impulses; each one triggers an individual heartbeat.

The electrical impulses leave the sinus mode and go across the atria, making the atria muscles contract. This atria muscle contraction pushes blood into the ventricles.

The electrical impulses continue to the atrioventricular node (AV node), a cluster of cells. The AV node slows down the electrical signals, and then sends them on to the ventricles. By delaying the electrical signals the AV node is able to give the ventricles time to fill with blood first. When the ventricle muscles receive the electrical signals they contract, pumping blood either to the lungs or the rest of the body.

When there is a problem with the electrical signals resulting in a faster-than-normal heartbeat, the patient has tachycardia. The most common types of tachycardia include:

Atrial fibrillation

When the two upper chambers - the atria - contract at an excessively high rate, and in an irregular way, the patient has atrial fibrillation. During atrial fibrillation the contractions of the two upper chambers of the heart are not synchronized with the contractions of the two lower chambers, causing rapid and irregular heartbeats. Atrial fibrillation is caused by chaotic electrical impulses in the atria; the AV node is bombarded with chaotic signals. An atrial fibrillation episode may last from a few hours to several days. Sometimes the episode does not go away without treatment. Most atrial fibrillation patients have some heart abnormality related to the condition.

Atrial flutter

The atria beats rapidly, but regularly. It is caused by a circuit problem within the atria. The contractions of the atria are weak because of the rapid heartbeat. There is a rapid and sometimes irregular ventricular rate, caused by rapid signals entering the AV node. An atrial flutter episode may last a few hours or some days. Sometimes it may not go away until treated. Atrial flutter is sometimes a complication of surgery, but it also can be caused by various forms of heart disease. Patients with atrial flutter commonly experience atrial fibrillation too.

Supraventricular tachycardias (SVTs)

Any tachycardic (accelerated) heart rhythm originating above the ventricular tissue. The abnormal circuitry in the heart if usually congenital (present at birth) and creates a loop of overlapping signals. An SVT episode may last from a few seconds to several hours. In one SVT form the AV node splits the electrical signal in two, with one signal going to the ventricles while the other goes back to the atria. There may also be an extra electrical pathway from the atria to the ventricles, effectively bypassing the AV node and resulting in a signal going down one pathway and up the other.

Ventricular tachycardia

Abnormal electrical signals in the ventricles result in a rapid heart rate. The speed of the heart beat does not allow the ventricles to fill and contract properly, resulting in poor blood supply to the body. This type of tachycardia is frequently a life threatening condition and is treated as a medical emergency. Ventricular tachycardia is linked to heart muscle damage from a previous heart attack or cardiomyopathy (disease of the heart muscle).

Ventricular fibrillation

The ventricles quiver in an ineffective way, resulting in poor blood supply to the body. If normal heart rhythm is not restored rapidly, blood circulation will cease and the patient will die. Patients with an underlying heart condition, or those who have been struck by lightning causing serious trauma may experience ventricular fibrillation.

Congenital heart disease

This is a general term for some birth defects that affect how the heart works. Congenital means you are born with it. In the UK it is estimated that 1 in every 1,000 babies are born with some kind of congenital heart disease. Examples include:

•   Septal defects - there is a hole between the two chambers of the heart. This condition is sometimes called hole in the heart.
•   Obstruction defects - the flow of blood through various chambers of the heart is partially or even totally blocked
•   Cyanotic heart disease - not enough oxygen is pumped around the body because there is a defect (or some defects) in the heart.

Congenital heart disease, also known as congenital heart defect, is a general term for a series of faults in the structure of the heart and great vessels that is present from birth. In the majority of cases, the defect either obstructs blood flow in the heart or nearby vessels, or causes blood to flow through the heart in an abnormal way. Congenital heart defect is a common birth defect, and a leading cause of deaths linked to birth defects. 

Congenital heart disease is far more treatable today than it used to be. A significant number of babies who once died of congenital heart defect today survive well into adulthood, thanks to advances in surgical treatment. Approximately 85% of newborns today with congenital heart defect survive well into adulthood. 

Even so, many adults who were initially treated for congenital heart disease may not be receiving adequate follow-up care. Adults who were treated as infants should check with their doctor. Patients may have complex health needs and might require life-long specialized care. 

According to the National Health Service (NHS), UK, there are over 30 different types of heart defect. The two main types of congenital heart defect are:

•   Cyanotic heart disease - the heart defect results in low blood oxygen levels. Babies suffer from breathlessness, fainting and fatigue. They typically have blue-colored toes, fingers and lips.
•   Acyanotic heart disease - blood oxygen levels are adequate, but the blood is not pumped around the body in a normal way. Symptoms may not be immediately apparent in newborns. The condition can cause problems over time. Blood pressure is higher than normal, making the heart work harder in order to pump blood, often weakening the heart. The patient may suffer from pulmonary hypertension (high blood pressure in the arteries in the lungs), causing breathlessness, fatigue, dizziness and fainting.

Approximately 6 in every 1,000 babies are born with some kind of congenital heart disease. Half of these babies will require surgery immediately after they are born, while the rest will likely need surgery at some time during the childhood. 

Certain genetic conditions, such as Down's syndrome, may raise the risk of congenital heart disease, as can an infection during pregnancy, such as rubella 

What are the signs and symptoms of congenital heart disease?

A symptom is something the patient senses and describes, while a sign is something other people, such as the doctor notice. For example, sleepiness may be a symptom while dilated pupils may be a sign. 

Signs and symptoms of cyanotic heart disease:

•   Breathing difficulties. A child may squat in an attempt to breathe properly
•   Chest pains
•   Cyanosis - the lips, fingers and toes are bluish
•   Delayed growth
•   Feeding difficulties, poor appetite
•   Hypoxia - low concentrations of oxygen in the body, during which the child may start hyperventilating
•   Sweating - especially when the baby is feeding
•   Syncope (fainting)
•   The child is typically underweight and small for his/her age.
• Signs and symptoms of acyanotic heart disease:
•   Breathlessness - especially during exertion
•   Chest pain
•   Delayed growth
•   Extreme fatigue
•   Feeding difficulties, poor appetite
•   Sweating - especially when the baby is feeding
•   The child is typically underweight.

Congenital heart disease signs and symptoms later in life - these may recur many years after the patient had treatment for a heart defect.

•   Arrhythmias - abnormal heart rhythms
•   Breathlessness
•  Cyanosis
•   Dizziness
•  Edema - swelling of organs or body tissues
•   Fatigue
•  Syncope (fainting)
•   The patient becomes easily tired after exertion.

What are the risk factors for congenital heart disease?

A risk factor is something which increases the likelihood of developing a condition or disease. For example, obesitysignificantly raises the risk of developing diabetes type 2. Therefore, obesity is a risk factor for diabetes type 2. 

Congenital heart disease is usually the result of a problem early on during the baby's development inside the womb. Some genetic and environmental risk factors may also contribute to the development of the condition, including:

•   Rubella - also known as German measles, is an infectious disease caused by the rubella virus. The virus passes from person-to-person via droplets in the air expelled when infected people cough or sneeze - the virus may also be present in the urine, feces and on the skin. The hallmark symptoms of rubella are an elevated body temperature and a pink rash. If a pregnant woman becomes infected with Rubella there is a serious risk of birth defects in the unborn baby. If the pregnant mother is infected within the first 20 weeks of pregnancy the child may be born with congenital rubella syndrome, which consists of a range of serious incurable illnesses, including congenital heart disease. Spontaneous abortion (miscarriage) occurs in up to one-fifth of pregnant women who become infected.
•   Diabetes Types I or II - if the mother had diabetes the development of the baby inside the womb may have been affected. Gestational diabetes is not linked to an increase in congenital heart defects for the baby.
•   Medications - some medications taken during pregnancy may raise the risk of congenital heart defects for the baby. Examples include isotretinoin (Accutane) for the treatment of acne, and lithium (Eskalith) for the treatment of bipolar disorder.
•   Alcohol consumption/abuse during pregnancy - women who consume alcohol during pregnancy may raise the risk of congenital heart defects for the baby.
•   Genetics - over 30% of children with Down syndrome have heart defects. A deletion of genetic material on chromosome 22 may case congenital heart defects - genetic tests are available for this. Experts say that in many cases congenital heart defects run in families. Turner syndrome and Noonan syndrome are both linked to congenital heart disease risk.

What are the causes of congenital heart disease?

The heart is a pump which consists of four chambers:

•   The left atrium
•   The left ventricle
•   The right atrium
•   The right ventricle.

..and four valves; they control bloodflow through the heart and around the body:

•   The mitral valve
•   The aortic valve
•   The tricuspid valve
•   The pulmonary valve.

The heart, along with the lungs supplies oxygen-rich blood to cells and tissues throughout the body. When blood is pumped into the lungs it collects oxygen, which is then transported to cells and tissues. Cells and tissues remove blood oxygen. The blood, which is now low in oxygen travels back to the heart and is then pumped into the lungs, etc. When there is a congenital heart disease there is something wrong with the structure of the heart, and the cycle does not work properly. Types of acyanotic heart disease

•   Ventricular septal defect (VSD) - the most common cause of acyanotic heart disease. There is a hole between the left and right ventricle. Blood pressure is higher on the left side of the heart than the right. If there is a hole, blood is pushed out of the left ventricle into the right ventricle. This means that the heart has to work extra to empty out the right ventricle - this puts a strain on the heart. The higher blood level can also cause pulmonaryhypertension (high pressure in the lungs). This can result in lung damage.
•   Atrial septal defect (ASD) - there is a hole between the left and right atriums. Similarly, the heart is under greater strain and there is potential lung damage.
•   Pulmonary stenosis - the pulmonary valve is abnormally narrow, consequently the heart is under greater strain to pump blood into the lungs.
•   Aortic stenosis - the aortic valve is abnormally narrow. The heart has to pump harder to get blood through the valve. This puts extra strain on the heart. Blood that goes through the aortic valve is crucial for the oxygen supply of many parts of the body. Patients with aortic stenosis may experience dizziness and breathlessness.
•   Patent ductus ateriosus (PDA) - this heart passage (duct) is supposed to close shortly after the baby is born when he/she begins to breathe normally. In a baby with PDA the duct does not close properly. Blood that is supposed to be pumped away from the lungs leaks back into the pulmonary valve and into the lungs. The heart and lungs have to work extra hard to make up for this problem.

Types of cyanotic heart disease

•   Tetralogy of Fallot (TOF) - the leading cause of cyanotic heart disease. It is a combination of four different heart defects: 

• 
  
•  Displaced aorta - the aortic valve is in the wrong place
•  Pulmonary stenosis - the pulmonary valve is abnormally narrow
•  Right ventricular hypertrophy - the muscles of the right ventricle are too thick
•  Ventricular septal defect - there is a hole between the left and right ventricle.

Oxygen-rich and oxygen-low blood get mixed up, resulting in poor oxygen supply to body organs and tissues. The child will typically be breathless and have blue skin.

§  Transposition of the great arteries (TGA) - the second most common cause of cyanotic heart disease. The aortic and pulmonary valves are connected to the each others' corresponding arteries. Instead of pumping low-oxygen blood to the lungs, it is pumped into the body, causing cyanotic heart disease.

Diagnosing congenital heart disease

Diagnosing before the baby is born (antenatal diagnosis) - a fetal echocardiography can be used to determine whether the developing fetus has congenital heart disease. The device is a kind of ultrasound scanner, specifically designed to create a picture of the insides of the chambers of the developing baby's heart. Typically, the test is done during the 18th to 20th week of pregnancy. This test may not detect mild cases. 

Diagnosing after the baby is born (postnatal diagnosis) - if the newborn baby has the hallmark signs of cyanotic heart disease - bluish coloring of the skin - diagnosis is usually made rapidly. Diagnosis of acyanotic heart disease often takes longer, in some cases not until the child is three years old. If the baby has problems feeding, is growing more slowly than expected, has shortness of breath after exertion, is tired after exertion, or has swelling of the hands, feet and ankles the doctor should be told immediately.

§  Echocardiogram - this ultrasound scan allows the doctor to see the heart muscles and valves.

§  Electrocardiogram (ECG) - this device records the patient's heart's activity. A technician placed probes on the skin of the chest which reveal the patterns of electric impulses through the heart as wave patterns. This test can assess how well the heart beats.

§  Chest X-ray - the aim here is to look at the size of the heart (is it too big), and whether there is too much blood in the lungs.

§  Pulse oximetry - this device measures oxygen saturation of arterial blood. A special sensor is placed on the patient's fingertip, ear or toe.

§  Cardiac catheterization - this test can determine how blood is pumping through the patient's heart. A catheter (a thin flexible tube) is passed into the right or left side of the heart, usually from the groin or the arm. The doctor is guided by X-rays or an MRI scanner. Once it is in place, the doctor may: 

§  Collect blood samples

§  Examine the heart arteries with a technique called fluoroscopy

§  Measure oxygen levels in various parts of the heart

§  Measure pressure and blood flow in heart's chambers and also in the large arteries around the heart

§  Take a small sample of heart muscle (biopsy)

The patient receives a local anesthetic.

Diagnosing adults with congenital heart disease - the doctor will perform a physical exam, and ask the patient questions about his/her medical and family history. If the doctor hears an abnormal heartbeat, it could be a sign of some lingering heart defect. The following diagnostic tests may be ordered:

§  Cardiac catheterization

§  Cardiac MRI (magnetic resonance imaging) scan - this imaging technique uses a magnetic field and radio waves to create images of the heart. The patient lies on a table inside a long doughnut/tube like machine that produces a magnetic field.

§  Chest X-ray

§  Echocardiogram

§  Electrocardiogram (ECG)

§  Exercise stress test - the patient exercises on a treadmill (running machine with a conveyor belt) to a standardized protocol. The speed and elevation are progressively increased, typically changing at three-minute intervals. The patient's EKG (electrocardiogram), heart rate (pulse rate), heart rhythm and blood pressure are monitored throughout the whole procedure.

What are the treatment options for congenital heart disease?

Sometimes congenital heart disease improves without treatment being required, or the defect may be so small that treatment is not needed. However, in the majority of cases the condition is serious and requires surgery and/or medications.

§  Catheters - this is a long, flexible tube that is inserted into the heart. Surgical tools are passed down through the catheter to repair heart defects. This type of surgery is non-invasive - the child will have no major surgical incisions in the chest.

§  Open heart surgery - in more serious cases the surgeon may have to operate directly on the heart. An incision is made on the child's chest so that damaged/defective parts of the heart can be repaired. The heart will be stopped and a machine pumps blood around the body during the operation.

§  Heart transplant - in very severe cases the damaged heart may need to be replaced for the patient to survive. The healthy heart of a child who has recently died replaces the surviving child's defective heart. Consent is needed from the deceased child's family.

§  Septal defects - if the child has a VSD (ventricular septal defect) or ASD (atrial septal defect), recommended treatment will depend on how serious the defect is. In mild cases the doctor may recommend watchful waiting - the child is monitored, but no treatment is given. Experts say that in the majority of mild cases the defect corrects itself in time. 

In mild to medium-sized defects a catheter may be used to seal the defect with a specially designed mesh. 

In more serious cases the doctor will probably have to perform open heart surgery. A patch will be stitched over the defect.

§  Stenosis (narrowing of the aorta or pulmonary valve) - treatment options here depend the severity of the stenosis. In mild cases the doctor will probably recommend a policy of watchful waiting. The child may also be given an antihypertensive medication (a drug to lower blood pressure). 

In a more serious case the doctor may perform a balloon angioplasty. A small balloon is passed through the catheter, when in position it is inflated, resulting in a widening of the targeted valve. The balloon is then removed. In some cases a stent (a metal coil) is used to stop the valve from narrowing again. 

In very serious cases the surgeon may have to replace the faulty valve. This will require open heart surgery. Replacement valves may be artificially made, taken from pigs and modified for human use, or obtained from human donors. 

The surgeon may use a relatively new technique using a catheter to replace the aortic valve (catheter insertion of a new aortic valve). There is not yet enough evidence to evaluate the long-term safety or effectiveness of this technique (March 2010).

§  Patent ductus ateriosus (PDA) - the patient will usually be given medication soon after birth. Examples include ibuprofen or indomethacin, to stimulate the closure of the duct causing PDA. If this does not work the surgeon may use a catheter to seal the duct with a plug or metal coil.

§  Tetralogy of Fallot (TOF) - babies with severe symptoms of breathlessness may require emergency surgery. A procedure called a BT (Blalock-Taussig) shunt is used. An artery is shunted (diverted) into the lungs so that blood can be enriched with oxygen before continuing on to the rest of the body. Later on, when the baby is older, open heart surgery will be performed where the defect between the ventricles is sealed and the pulmonary valve is repaired.

§  Transposition of the great arteries (TGA) - this is done soon after the birth of the baby. It requires open heart surgery, using a technique called an arterial switch. The arteries are cut and reattached to their correct positions on the other side of the heart (to the pulmonary and aortic valves).

Congenital heart disease treatment for adults - as with babies and children, treatment options for adults vary, and depend on several factors, including the severity of the disease. The doctor may recommend treatment to correct the heart defect, or therapy to treat the complications caused by the defect.

§  Watchful waiting (regular checkups) - if defects are relatively minor, there may only be periodic checkups to determine whether the patient's condition has worsened.

§  Medications - in some mild cases medications may be administered to help the heart work better (and no other treatment).

§  Catheters - as in the case with babies and children, catheterization techniques may be used to repair some congenital heart defects, without the need for open heart surgery.

§  Open heart surgery - in more complicated or serious cases the doctor may have to perform open heart surgery. These are major medical procedures and recovery times can be lengthy.

§  Heart transplant - if the defect cannot be repaired the patient may need a new heart.

It is wrong to believe that treatment during childhood means that the problem has gone away and no further follow-up is required - this is rarely the case. Treatment for congenital heart disease does not cure it. Patients are at increased risk of developing complications throughout their lives. Some may require further surgery later on in life. 

Adults who have had congenital heart disease treatment as children should liaise with their doctor about follow-up care, which should be carried out periodically for the rest of their lives. Checkups should ideally be done with cardiologists who are trained in monitoring adults with congenital heart diseases. It may not always be easy to find one. 

Pregnancy - a woman with a congenital heart disease should talk to her doctor before planning to become pregnant. Although the majority of patients have normal pregnancies, it is important to discuss the risks, as well as any special care that may be required during pregnancy. Couples trying to have children who have congenital heart disease may benefit from genetic counseling, where they may learn about the risks of passing on the disease to their offspring