Chest pain is a frequent reason for emergency department visits, but in more than 50% of cases, the discomfort does not originate from the heart itself. This is known as non-cardiac chest pain (NCCP), a diagnosis of exclusion made after a comprehensive medical evaluation has ruled out ischemic heart disease. The sensation of pain can still be severe, often described as pressure or squeezing behind the breastbone, which makes immediate medical assessment necessary. Understanding the diverse non-cardiac origins of this pain helps patients and clinicians navigate the diagnostic process.
Causes Originating in the Digestive System
Gastroesophageal Reflux Disease (GERD) is the most common underlying factor in non-cardiac chest pain, accounting for an estimated 20% to 60% of cases. The esophagus and the heart share nerve pathways, meaning irritation in the esophagus can be misinterpreted by the brain as cardiac distress. This anatomical overlap allows digestive issues to present as chest pain.
The reflux of stomach acid causes a burning sensation, or heartburn, which can mimic the oppressive, squeezing feeling of angina. This discomfort is often felt centrally behind the sternum and may be accompanied by a sour taste or difficulty swallowing. Unlike cardiac pain, this discomfort may be positional, sometimes improving when a person sits or stands upright.
Muscular dysfunction of the esophagus, such as diffuse esophageal spasms, can also generate intense chest pain. These involuntary contractions of the food pipe cause sudden, severe episodes of pain lasting minutes or hours. The pain is related to the powerful, uncoordinated squeezing of the esophageal muscle wall, which can feel like crushing pressure in the chest.
Causes Originating in the Chest Wall and Muscles
Pain arising from the musculoskeletal structures of the chest wall is a common cause of non-cardiac chest pain. The most frequent condition is Costochondritis, which is the inflammation of the cartilage connecting the ribs to the breastbone (costochondral junctions). This inflammation typically affects the junctions of the second through fifth ribs.
A defining characteristic of Costochondritis is that the pain is reproducible by pressing on the affected area. The discomfort is often described as sharp or dull and can worsen with movement, deep breaths, coughing, or sneezing. This localized tenderness points to a muscular or skeletal origin rather than a cardiac one.
Muscle strains in the chest area can also cause significant pain, often resulting from strenuous upper body exercise or forceful coughing. The intercostal muscles, which run between the ribs, are vulnerable to strain that produces a persistent, aching discomfort. Injuries to the ribs themselves, even minor ones, similarly cause pain that intensifies with movement or deep respiration.
Causes Originating in the Lungs and Airways
Respiratory conditions can lead to chest pain through inflammation or irritation of the tissues surrounding the lungs. Pleurisy involves inflammation of the pleura, the two thin layers of tissue that line the lungs and the inner chest wall. Normally, fluid allows these layers to glide smoothly past each other during breathing.
When the pleura becomes inflamed, the layers rub together like sandpaper, generating a sharp, stabbing pain known as pleuritic pain. This discomfort is worsened by deep inhalation, coughing, or sneezing, as these actions increase the friction between the irritated membranes. Other respiratory infections like pneumonia or bronchitis can cause chest pain when the associated deep coughing strains the chest wall muscles and irritates the airways.
Neurological and Stress-Related Causes
Psychological factors, specifically anxiety and panic attacks, are triggers for physical chest pain. During a panic attack, the body initiates a fight-or-flight response, flooding the system with stress hormones like adrenaline. This hormone surge causes a rapid heart rate and increased muscle tension across the chest wall.
Hyperventilation, which is rapid, shallow breathing common during anxiety episodes, can disrupt the body’s balance of oxygen and carbon dioxide, leading to muscular spasms and chest discomfort. The pain associated with these episodes is often described as sharp, stabbing, or a crushing pressure. This cycle of anxiety and physical symptoms can be severe.
A neurological cause of chest pain that can precede a visible skin rash is Shingles, caused by the reactivation of the varicella-zoster virus. The virus attacks the nerve pathways, resulting in a deep, burning, or tingling pain on one side of the chest wall. This pain can manifest days or even weeks before the characteristic blistering rash appears, making the initial diagnosis challenging.