Introduction
Chest pain at its most basic level is the body warning itself about injury or possible injury to a structure in the chest. The chest contains many different structures so pinning down the source of the pain can be difficult. Parents and patients are usually very upset about this common symptom because they know that in adults chest pain often signifies myocardial infarction (heart attack). However, cardiac causes of chest pain are among the least likely causes in pediatric patients. Symptoms are chronic in over half of the patients seen, but 81% of these resolve over time.

There are two main types of pain that can help the doctor to decide where the symptom is coming from. The first type is somatic pain, which is usually described as sharp, burning, stabbing, and is often easy to point to. Somatic pain arises from the skin or just under it, or may come from muscle and bones. The second type is visceral pain, which originates in organs and body cavity linings. It is frequently described as dull, pressure or vice-like, and it can be difficult to point out a specific area affected. Armed with knowledge of which of these pain types is affecting the patient, the doctor can significantly narrow down the number of possible diagnoses.

1) Idiopathic Chest Pain

The most common cause of chest pain is idiopathic, meaning that no organic or psychological cause for the pain is ever found by medical work up, accounting for 12-85% of all pediatric chest pain. This cause is most common in adolescent females during periods of rapid growth. This is a diagnosis of exclusion, being made only when all other tests have been inconclusive, and most often resolves on its own over time.

2) Musculoskeletal Chest Pain

Diagnosed in 15-30% of cases, musculoskeletal pain is usually the result of muscle strain or overuse. Symptoms often follow physical exercise like weight lifting, pushups or school sports, especially if the patient is not used to such activity. Musculoskeletal chest pain is generally somatic pain and can be reproduced in the office by the physician in the majority of cases. The following are causes other than muscle strain:

• Costochondritis—An inflammation of the cartilage connecting the ribs to the sternum. This syndrome is most common in females, and the pain can be easily reproduced in the office.
• Tietze Syndrome—Similar to costochondritis, but has a noticeable swelling of the affected cartilage to bone junction.
• Slipped Rib Syndrome—This syndrome is caused by an increased mobility of the 8th to 10th ribs (which are not attached to the sternum like the other 7 pairs). Patients often feel a clicking or slipping movement in the chest with movement or lifting. Doctors can reproduce the pain by using the "hooking maneuver" and pulling the lower ribs toward the front of the body.
• Breast Masses—Breast masses can be found in males and females during puberty and are a source of chest pain. After menstruation begins, girls often have breast pain that changes with menstrual cycle. Breast masses in children and adolescents are nearly always benign.

3) Pulmonary Chest Pain

Chest pain originating in the lung explains 12-21% of cases, and is more common in children under 12 years old. Most pulmonary causes can be diagnosed by chest x-rays and listening with the stethoscope. The three most common sources are asthma, pneumonia and chronic cough. The majority of pulmonary chest pain is made worse with deep breathing or coughing and is often sharp in character; this is called "pleuritic" pain. In addition to these three, other, rarer causes follow:

• Asthma—A reactive airway disease often found in children. The spasm of airways may cause difficulty breathing, wheezing and pain.
• Pneumonia—A lung infection caused by virus or bacteria that may cause shortness of breath, cough and chest pain. Usually accompanied by fever.
• Chronic Cough—Pain is from either strain on the muscles between the ribs or from irritation of airways, both from overuse in coughing fits.

• Pleurodynia—A pain syndrome caused by Coxsackie virus that causes spasms of sharp pain in the chest, often with fever.
• Pulmonary Embolus—Pain caused by a blood clot in the lung circulation that causes death of lung tissue. Pain is sudden and is often associated with difficulty breathing. This occurrence is very rare in children unless they are already predisposed to blood clotting disorders or are adolescent females on birth control pills.
• Pneumothorax—Air enters the space around the lung, which may lead to a collapse of the lung and inability to breath adequately. It may happen spontaneously in teenagers, or after trauma and can be a medical emergency. Symptoms vary based on the extent of the pneumothorax and may include pain with breathing, difficulty breathing and even loss of consciousness.
• Acute Chest Syndrome—Only found in patients with sickle cell disease. This pain syndrome is caused by an acute sickling crisis of the pulmonary blood supply.

4) Psychological Chest Pain

Psychological causes in the absence of organic causes account for 5-17% of chest pain in pediatrics. There is an increased frequency in females. Most often the patient has one or more significant life stressors that precede the pain, such as death of a family member, school problems, divorce in the family, fights or problems with peers, abusive or violent families, etc. Hyperventilation also falls into this category of problems.

5) Gastrointestinal Pain

Pain coming from the esophagus, gut and liver is only implicated in 4-7% of chest pain cases. The two most common causes are as follows:

• Esophageal reflux—This is common heartburn, caused by a reflux of acid stomach contents back up into the esophagus. Usually described as a burning pain in the center of the chest, sometimes with the feeling of acid or liquid in the back of the throat. Symptoms are increased or decreased by different foods, and by body position.
• Cholecystitis—Gallstones are occasionally a cause of lower right sided chest pain, most common after meals. Gallstones are uncommon in pediatric patients, but not unknown.

6) Cardiac Chest Pain

The heart is the cause of chest pain in only 4-6% of cases. Even of those patients referred to cardiologists only 5-15% had a cardiac cause for their pain. Of course, though they are rare, cardiac causes are important because they tend to be the most dangerous of all the causes of chest pain. A history of syncope (fainting), palpitations, previous cardiac surgery or a family history of unexplained early deaths all raise suspicion of cardiac problems. The tests used for working up cardiac pain are careful listening with the stethoscope, ECG, and occasionally an echocardiogram.

Another type of pain that is found predominantly in heart causes of chest pain is "ischemic" or "angina"—described as crushing or pressure on left side of chest or on center of chest sometimes radiating to left arm. Ischemic pain is usually felt with or after exertion, builds to a peak then subsides, lasting only minutes. This type of pain is due to decreased oxygen reaching the muscle cells of the heart itself. The following are the most common sources of cardiac pain:

• Hypertrophic Obstructive Cardiomyopathy—This is a structural abnormality of the heart with a genetic transmission in families. Symptoms include ischemic pain, shortness of breath, fatigue, difficulty breathing while lying flat, fainting, and heart palpitations. This abnormality carries a risk of sudden death.
• Severe aortic and pulmonic valve stenosis—These valve abnormalities may cause ischemic chest pain because the heart is not receiving enough oxygenated blood to keep it functioning well.
• Mitral Valve Prolapse—The mitral valve in some people is floppy and is sometimes associated with a heart murmur and a clicking noise heard with the stethoscope. The cause of the chest pain in these patients is not very well known.
• Pericarditis—This is an infection or inflammation of the sack that surrounds the heart. Found often with autoimmune disorders or after a viral illness.
• Myocarditis—This is inflammation of the heart muscle itself and is similar to pericarditis.
• Kawasaki syndrome—An infectious illness that may lead to small aneurysms of the arteries to the heart which then may get plugged or ruptures, thereby reducing blood flow to the heart.
• Drug use—Adolescents using cocaine may have spasm of the arteries to the heart leading to chest pain and possibly heart attack. Nicotine from cigarettes can also cause chest pain.
• Arrhythmias—These heart rhythm disturbances are common in children, most being harmless. A few of these arrhythmias can be dangerous, such as ventricular and supraventricular tachycardias. Symptoms are usually the feeling of palpitations (the uncomfortable feeling of the heart beating, possibly in an irregular fashion), feeling that the heart is skipping beats, and chest pain. ECG is often diagnostic in these cases, but sometimes patients are put on a Holter monitor for 24 hours to watch for unexplained changes in rhythm.

References

For further reading about this subject and a more complete list of all possible etiologies of chest pain in pediatrics, try: