Non-cardiac chest pain (NCCP) is a term used to describe chest pain that resembles heart pain (also called angina) in patients who do not have heart disease. The pain typically is felt behind the breast bone (sternum) and is described as oppressive, squeezing or pressure-like. It may radiate to the neck, left arm or the back (the spine). It may be precipitated by food intake. It lasts variable periods of time and it is not unusual for it to last hours. Patients may also complain of associated reflux symptoms such as heartburn (a burning feeling behind the breast bone) or fluid regurgitation (a sensation of stomach juices coming back toward the chest and even to the mouth frequently with a bitter or sour taste).
Because the pain is similar to heart pain (called angina), patients and physicians frequently attribute this pain to the heart. In fact, many patients present to emergency rooms concerned about a heart attack and commonly undergo cardiac studies (such as EKGs, laboratory tests, stress test and even coronary angiography – where dye is injected into the heart vessels). After these cardiac tests fail to show evidence of heart disease, the patients receive the diagnosis of NCCP, leading the physician to examine other causes for this chest pain.
The heart and the esophagus are located in the chest cavity (thorax) in close proximity (Figure 1). They receive very similar nerve supply. Thus, pain arising from either organ travel through the same nerve sensory fibers to the brain. As a result, the pain from either organ can have very similar features making it difficult to differentiate cardiac pain from esophageal (swallowing pipe) pain. It also indicates that a very common source of chest pain (non-cardiac) arises from the esophagus.
Figure 1. The heart and the esophagus are located in the chest in close proximity and also share same sensory nerves.
A variety of names have also been used in describing patients with NCCP. You may hear your doctor or other health care professional call it: “atypical chest pain, chest pain of undetermined origin, unexplained chest pain, functional chest pain, soldier’s heart, irritable heart, sensitive heart, neurocirculatory asthenia, DaCosta’s syndrome, and chest pain with normal coronary angiograms.”
The sources of NCPP can be grouped into esophageal and non-esophageal. Several studies have shown that approximately 60% or more of patients with NCCP suffer from acid reflux (mostly due to what is commonly referred to as Gastroesophageal Reflux Disease). Therefore, patients having chest pain who have had a negative cardiac evaluation are frequently referred to gastroenterologists (digestive disease specialists) to evaluate the esophagus as source of their chest pain.
Some of patients with NCCP have also been found to suffer from stress that leads to disturbances such as depression, anxiety or panic disorder. It is unclear whether the stress disorder came first or the chest pain led to the appearance of an emotional disorder. Treatment of these conditions is an important component of treating chest pain.
NCCP can occur in children as well as older patients, it also affects men and women and some studies have suggested a higher proportion of patients are female. The reasons some studies have found women may have a higher frequency of NCCP than men is not well understood.
NCCP is a very common problem of international proportions. Population studies have shown that in the United States as many as 70 million patients (23% of the population) suffer from NCCP. Similar figures have been described in Australia (33%), Spain (8-28%), Argentina (24%), and South China (21%). No other specific risk factors have been identified.
Patients suffering from chest pain must have thorough cardiac evaluations to ensure they do not have heart disease prior to being labeled as having NCCP. In addition, a variety of other disorders described above, both esophageal and non-esophageal must also be considered since specific treatment for these disorders are available.
Once cardiac tests have concluded that patients do not have heart disease, patients are commonly offered a treatment trial of acid suppressive inhibition medications (called a PPI - proton pump inhibitor - trial) for about 2 weeks. This is frequently referred as “a PPI trial” and can be both diagnostic and therapeutic since if it relieves the chest pain it suggests that acid-reflux is likely the cause. Thus, if pain is improved the treatment may be extended for a longer period of time such as 2 months. If the patient does not improve after “a PPI trial”, further testing may be done. Those studies may include a pH study of the esophagus (a test to actually measure the amount and determine if there is acid reflux) an upper endoscopy (a scope with a light that is introduced in the esophagus and stomach to check for other conditions that may cause chest pain), an esophageal motility test (a test to study the esophagus muscle contractions) and perhaps an ultrasound of the abdomen to examine the gallbladder for possible stones.
Sami R. Achem, MD, FACG, Mayo College of Medicine, Mayo Clinic, Jacksonville, FL – Published February 2009. Updated July 2013.