Pharmacists are in a unique position within the health care community. Patients feel free to question pharmacists about various symptoms they or their family members are experiencing. Many complaints are trivial and easily treated with nonprescription products, but some are possible manifestations of serious disease. Chest pain (usually in the substernal area) is one of the latter, as it may indicate cardiac pathology, and heart disease is the leading cause of death in the United States.1

Prevalence
Chest pain is experienced by 25% of people in the U.S.2 At least 1% to 2% of visits to physicians are caused by concern about chest pain.1,3 Chest pain is responsible for 5.5 to 5.8 million visits to emergency rooms each year.4 Despite the potential gravity of this symptom, perhaps 77% of patients who experience it refuse to make an appointment with a physician.5

Cardiac Versus Noncardiac Chest Pain
Chest pain has an extensive differential diagnosis. The typical patient with the first bout of chest pain immediately fears the onset of cardiac pathology, such as ischemic cardiac disease, but only 11% to 39% of these patients are eventually found to have coronary artery disease.2 Furthermore, only about 45% to 50% of patients visiting emergency rooms for chest pain actually have cardiac-related chest pain.2,3 The balance of patients (50% to 55%) experience noncardiac chest pain.5

The relative risks of either cardiac or noncardiac chest pain are markedly different when patients presenting to emergency departments and those seen in outpatient primary care are examined separately. In emergency care patients, over half of those withchest pain receive a diagnosis of myocardial infarction, angina, pulmonary embolism, and heart failure.1 In outpatient primary care, on the other hand, the most common cause is gastroesophageal reflux disease (GERD), followed by musculoskeletal conditions, other gastrointestinal conditions, psychiatric conditions (e.g., panic disorder), pulmonary disease, or stable coronary artery disease.1,6 Some of the conditions causing chest pain are less serious but still require physician diagnosis (e.g., GERD uncontrolled by nonprescription products, panic disorder, peptic ulcer disease, chest wall pain). Others pose greater risk to the patient's life, such as stable or unstable coronary artery disease, pulmonary embolism, and pneumonia. Virtually all require physician referral. The sole exception might be heartburn or gastroesophageal reflux, potentially self-treatable with omeprazole, H2 antagonists, or antacids, assuming all FDA-required labels are followed closely.

Chest Pain Requiring Emergency Care
Several potential causes of chest pain require emergency care,7 which are included here in order to stress that all require an immediate physician visit. One such diagnosis is acute coronary syndrome, including acute myocardial infarction and unstable angina; both require an electrocardiogram for diagnosis. Typical anginal pain has three characteristics: It is substernal, it is brought on by exertion, and it is relieved by either rest or nitroyglycerin.1 Anginal pain is also brief, with a duration of five to 15 minutes.4 A myocardial infarction is more likely if the patient has diaphoresis, pain radiating to both arms, and low blood pressure.1 Alternatively, the patient may have a hypertension-induced aortic dissection, in which there is a tear in an aortic wall. The chest pain of aortic dissection is a ripping, tearing, or knife-like pain that begins suddenly at peak intensity, along with neurological or pulse abnormalities.1,4 aortic dissection may be treated with medication or surgery, depending on the nature of the tear.

Chest pain can be caused by acute pericarditis, perhaps following a viral illness. In this condition, chest pain radiates to the back, neck, or shoulders and often worsens when the patient inhales. It improves if the patient sits upright or leans forward. The pain is traditionally accompanied by dyspnea and fever.

Pulmonary embolism may cause a sudden onset of pleuritic chest pain.4,7 Additional manifestations are fatigue, dyspnea, fainting, spitting up blood, and cardiac arrest. An EKG helps confirm the diagnosis.

Pneumothorax is a potential cause of pleuritic, sharp, and sudden chest pain, usually accompanied by shortness of breath.7 Patients often have a history of cigarette use or have chronic obstructive pulmonary disease.8

Severe chest pain can occur following perforation of the esophagus, most often in patients ages 63 to 71. 7 Additional manifestations include vomiting, shortness of breath, dyspnea, cough, fever, and abdominal pain. A chest X-ray, endoscopy, or other emergency diagnostic procedure is needed to confirm perforation; prompt confirmation can be lifesaving.

Approximately 5.6 million individuals each year in the U.S. contract community-acquired pneumonia, another potential diagnosis for those with chest pain.9 Pneumonia pain may be pleuritic, sharp, dull, or substernal.7 Other manifestations are dyspnea, fever (over 100.4°F), malaise, fatigue, cough (productive or nonproductive), altered breath sounds, wheezing, and rales. 4,7 A chest X-ray, CAT scan, or bronchoscopy can confirm this diagnosis, allowing the clinician to begin antibacterial therapy.

Nonemergency Chest Pain
There are other causes of chest pain that require physician care, although an immediate visit to the emergency room is not necessary. These include panic disorder, depression, various gastrointestinal diseases, chest wall syndrome, and nerve root compression.6,7 Panic disorder causes a broad set of symptoms such as palpitations, diaphoresis, tremor, dyspnea, choking, nausea, dizziness, fear of losing control or dying, tingling of the extremities, hot flashes, and chills. Some gastrointestinal conditions that can cause chest pain are reflux, spasm of the esophagus, pancreatitis, and peptic ulcer. If the problem is due to reflux, the patient will also describe the postprandial sensation of food moving upward from the stomach.1,4 Chest wall pain is often acute, localized, and sharp, worsening with movement or a deep breath, and dyspnea is often present.1 Patients with chest wall pain may have a history of rheumatoid arthritis or osteoarthritis.1 If the cervical/thoracic nerve roots become compressed, they cause an angina-like pain that is worse if the patient moves the neck, coughs, or sneezes.

Chest Pain in Young Athletes
Pharmacists are occasionally approached by a worried young athlete or his or her parent(s). In a typical scenario, the youth has experienced substernal chest pain during an athletic event.10 The family is understandably bewildered, since prior to the episode, the youth appeared to be at the peak of ability, in excellent shape, and with no apparent health problems. Undoubtedly, the patient was cleared for exercise by a physician. The family may be in the midst of recriminations and guilt for allowing the youth to engage in sports in the first place, supposing that the youth has now developed a serious cardiac condition as a result.

The prognosis is actually quite favorable, because only about a dozen young athletes die each year from undetected cardiac disease. In those who do, the probable causes are rare conditions, such as hypertrophic cardiomyopathy or congenital coronary artery anomalies.10 The low risk of serious pathology is largely misunderstood by the lay public, as the few unfortunate sudden deaths in young athletes seem to garner widespread publicity. First and foremost, the pharmacist must urge the family to visit a physician. The most frequent diagnosis is exercise-induced asthma, and the most common venue for its occurrence is a cold, dry ambient environment, such as a hockey rink. The patient may have also experienced gastroesophageal reflux, a problem for those engaging in sports with pronounced vertical movement, such as running and jumping. The cause may also be the well-known "stitch" in the side. This is a common pain located over the lower left rib cage; it may be caused by strain or a spasm of the muscles supporting the diaphragm.

Cocaine-Induced Chest Pain
Chest pain is the leading medical complaint among cocaine abusers. In urban areas, it is thought to be responsible for 14% to 25% of chest pain episodes; the estimate in suburban areas is only 7%.11 However, patients are not likely to reveal a history of illicit drug abuse to the pharmacist or physician.

Conclusion
Pharmacists are likely to be approached by patients who complain of chest pain. The differential diagnosis of chest pain is extensive, including many lethal diagnoses. In virtually every case, the prudent pharmacist will encourage the patient to seek emergency medical care.

References
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8. Niewoehner DE. The impact of severe exacerbations on quality of life and the clinical course of chronic obstructive pulmonary disease. Am J Med. 2006;119(Suppl 1):38-45.
9. Lutfiyya MN, Henley E, Chang LF, et al. Diagnosis and treatment of community-acquired pneumonia. Am Fam Physician. 2006;73:442-450.
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11. Jones JH, Weir WB. Cocaine-induced chest pain. Clin Lab Med. 2006;26:127-146.
12. Cava JR, Sayger PL. Chest pain in children and adolescents. Pediatr Clin North Am. 2004;51:1553-1568.

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