Chest Pain: How Doctors Determine What Is Cardiac and What Is Something Else

Chest pain is one of the most common and highest-stakes complaints in emergency medicine. Approximately 8 million Americans visit emergency departments for chest pain each year, making it the second most common emergency department chief complaint. Of these, roughly 15 to 20 percent are ultimately found to have a cardiac cause — which means 80 percent or more have a non-cardiac explanation. The challenge is that distinguishing cardiac from non-cardiac chest pain in real time, without adequate testing, is reliably difficult even for experienced clinicians. History, quality of pain, and associated symptoms all provide valuable information, but they are not definitive. The evaluation of chest pain is one of the clearest illustrations of why clinical testing exists: to reduce diagnostic uncertainty in situations where being wrong carries catastrophic consequences.

Cardiac Causes of Chest Pain

Acute Coronary Syndrome (ACS)

Acute coronary syndrome — encompassing ST-elevation myocardial infarction (STEMI), non-ST-elevation MI (NSTEMI), and unstable angina — represents the spectrum of conditions caused by acute reduction in coronary blood flow, usually from plaque rupture with overlying thrombus formation. ACS is the most time-sensitive cause of chest pain, with myocardial death occurring within minutes to hours of ischemia onset. Classic presentation is substernal chest pressure or tightness, often described as a weight, squeezing, or crushing sensation (patients frequently avoid the word "pain," saying instead "pressure" or "heaviness"), radiating to the left arm, jaw, or neck, associated with diaphoresis (cold sweat), nausea, and shortness of breath. Onset is typically during exertion or at rest. Duration lasting more than 20 minutes, unrelieved by nitroglycerine, suggests MI rather than unstable angina. STEMI requires emergent reperfusion (percutaneous coronary intervention, or primary PCI, within 90 minutes of first medical contact in a PCI-capable center) — door-to-balloon time is a critical quality metric because every 10-minute delay costs myocardium.

Stable Angina

Stable angina is chest discomfort produced predictably by exertion or emotional stress and relieved within 5 to 15 minutes by rest or sublingual nitroglycerine. It reflects fixed coronary artery stenosis adequate to limit blood flow during increased demand but insufficient to cause infarction at rest. Stable angina is not an emergency, but it is a symptom of significant coronary artery disease that warrants urgent outpatient evaluation, risk stratification, and management to prevent progression to ACS.

Pericarditis

Pericarditis is inflammation of the pericardium (the sac surrounding the heart), most commonly caused by viral infection (Coxsackie B, adenovirus, influenza, COVID-19) or idiopathic in origin. The pain is typically sharp, pleuritic (worsened by deep inspiration), positional (improved by sitting forward — the classic "prayer position"), and may radiate to the left trapezius ridge (a pericardium-specific referral pattern caused by phrenic nerve irritation). ECG changes in acute pericarditis include diffuse saddle-shaped ST elevation and PR depression in virtually all leads — a distinctive pattern different from the focal territorial ST changes of MI. Troponin may be mildly elevated if myocardial inflammation (myopericarditis) co-exists. Treatment is NSAIDs plus colchicine for six months; exercise restriction during the acute phase.

Aortic Dissection

Aortic dissection — tearing of the aortic intima with blood entering the medial layer — is among the most immediately lethal causes of chest pain. Classical description is sudden onset, "tearing" or "ripping" chest or back pain (interscapular with descending aorta involvement) that is maximal at onset, unlike MI which typically builds over minutes. Blood pressure asymmetry between arms (greater than 20 mmHg difference), pulse deficits, neurological symptoms, or a new aortic insufficiency murmur all suggest dissection. Type A dissection (involving the ascending aorta) requires emergency surgery; Type B (descending only) is initially managed medically with aggressive blood pressure and heart rate control. The diagnosis is made by CT angiography. Thrombolytics and anticoagulants — appropriate for MI — are catastrophically harmful in dissection, making accurate differentiation urgent.

Pulmonary Embolism

Pulmonary embolism (PE) is caused by thromboembolism obstructing a pulmonary artery, and its presentation overlaps substantially with cardiac chest pain. Pleuritic chest pain (worse with breathing) combined with dyspnea is the classic presentation, though the majority of PEs present with dyspnea alone. Risk factors include recent immobilization, surgery, cancer, prior DVT or PE, oral contraceptive use, pregnancy, and long-distance travel. Massive PE (causing hemodynamic instability) presents as acute cardiovascular collapse. ECG findings in PE include sinus tachycardia, S1Q3T3 pattern (not specific), right bundle branch block, or T-wave inversions in V1–V4 (reflecting right ventricular strain). CT pulmonary angiography is the diagnostic standard. PE shares the urgency of ACS — massive PE may require thrombolysis or embolectomy, and untreated submassive PE carries significant mortality.

Non-Cardiac Causes of Chest Pain

Gastroesophageal Reflux Disease (GERD) and Esophageal Spasm

GERD is the most common non-cardiac cause of chest pain in outpatient and emergency settings. The pain is typically burning, substernal, worsened after meals, when lying flat, or after alcohol or spicy foods, and relieved by antacids. It can, however, mimic cardiac pain — nitroglycerine can relieve esophageal spasm as well as angina, making clinical differentiation unreliable. Esophageal spasm produces intense, diffuse substernal chest pain that can radiate to the jaw and arms, often described as crushing, with a presentation clinically indistinguishable from MI before testing. The "GI cocktail" (antacid with viscous lidocaine) sometimes relieves esophageal chest pain and can be diagnostically suggestive, but its failure to relieve symptoms does not confirm a cardiac cause.

Costochondritis

Costochondritis is inflammation of the costochondral junctions — where the ribs join the cartilage that connects them to the sternum. It produces chest pain that is sharp, localized, and reproducibly elicited by palpation of the chest wall. The presence of tenderness to palpation is a key distinguishing feature: cardiac ischemic pain is not reproducible by pressing on the chest. Young, otherwise healthy patients who present with sharply localized chest pain that worsens with movement or touch and is tender on examination are very likely to have a musculoskeletal cause. Treatment is NSAIDs and reassurance. However, costochondritis coexists with cardiac disease — a tender chest wall does not exclude cardiac pathology in a patient with multiple risk factors.

Anxiety and Panic Disorder

Panic attacks produce intense chest tightness, palpitations, shortness of breath, diaphoresis, and a sense of impending doom — a symptom constellation that is clinically difficult to distinguish from ACS without testing, particularly in the emergency department. Patients with panic disorder present to emergency departments frequently, often after multiple negative workups for cardiac disease. The diagnosis of anxiety-related chest pain should only be made after cardiac and pulmonary causes have been reasonably excluded — not as a default when no immediate pathology is found. Conversely, many patients with established anxiety disorder develop real cardiac disease, and dismissing their symptoms based on psychiatric history is a known source of missed MI.

Pleuritis and Pneumonia

Pleural inflammation from any cause — infection (pneumonia with parapneumonic pleuritis), autoimmune disease, post-viral pleuritis — produces sharp, localized, pleuritic chest pain worsened by deep inspiration, coughing, or movement. Associated fever, cough, and dyspnea are common. Auscultation may reveal a pleural friction rub. Chest X-ray usually identifies pneumonia or pleural effusion.

How Emergency Physicians Evaluate Chest Pain

When you present to an emergency department with chest pain, evaluation begins immediately because the most time-sensitive diagnosis (STEMI) requires a decision within minutes. The standard evaluation sequence:

12-Lead ECG

An ECG should be obtained within 10 minutes of presentation in all patients with chest pain. STEMI diagnosis can be made immediately from the ECG — ST elevations in two or more contiguous leads in the right distribution, with the patient's symptoms, are sufficient to activate the cardiac catheterization laboratory. Other ECG findings help identify ischemia (ST depressions, T-wave changes), PE (right heart strain pattern), pericarditis (diffuse changes), or arrhythmia as a cause of symptoms. A normal ECG does not exclude ACS — approximately 6 percent of MIs present with a normal initial ECG.

High-Sensitivity Troponin

Troponin I and T are cardiac-specific proteins released into the bloodstream when myocardial cell injury occurs. High-sensitivity troponin assays (hs-cTn) detect very small amounts of myocardial injury and can identify NSTEMI much earlier than older assays. Serial troponin measurements — typically at presentation (time 0) and one to two hours later — are used to identify a significant "delta" (rise and fall pattern consistent with acute myocardial injury). A troponin value above the 99th percentile upper reference limit with the appropriate clinical context defines MI. Troponin can also be elevated by non-ischemic causes: myocarditis, PE, pericarditis, sepsis, acute kidney injury, and heart failure — context matters as much as the number.

Imaging

Chest X-ray evaluates for pneumonia, pneumothorax, pleural effusion, widened mediastinum (suggestive of dissection), or pulmonary edema. CT pulmonary angiography is definitive for PE. CT aortogram is used for dissection. Coronary CT angiography (CCTA) is increasingly used in low-to-intermediate risk chest pain patients to rapidly exclude significant coronary artery stenosis and allow safe discharge. Bedside echocardiogram can identify wall motion abnormalities (focal ischemia), pericardial effusion, or right ventricular dilation (PE).

The Typical vs Atypical Distinction

"Typical" anginal chest pain is defined by three features: substernal location, provocation by exertion or emotional stress, and relief with rest or nitroglycerine. "Atypical" angina lacks one of these three, and "non-anginal" chest pain lacks two or more. The typical/atypical framework has clinical utility for probability estimation but has well-established limitations in certain populations.

Women's Different Presentation of Cardiac Disease

Women with ACS less frequently present with the textbook substernal pressure radiating to the left arm. They more often present with shortness of breath, fatigue, nausea, back pain, jaw pain, and epigastric discomfort — symptoms that may be attributed to anxiety, GI disease, or other non-cardiac causes. This difference in presentation, combined with historical under-recognition of cardiovascular disease in women, has contributed to documented disparities in time-to-treatment and outcomes for women with ACS. Women are more likely to be diagnosed as "atypical" and subjected to longer diagnostic delays. Heightened clinical awareness of this pattern is essential — particularly since obstructive coronary artery disease combined with microvascular dysfunction (smaller vessel disease affecting women more than men) produces real ischemia with presentations that standard testing can miss.

When to Call 911 vs Urgent Care vs Routine Visit

Call 911 immediately for: sudden onset severe chest pain, chest pain with shortness of breath, diaphoresis or cold sweats, pain radiating to jaw/neck/left arm, chest pain with dizziness or loss of consciousness, tearing or ripping chest or back pain (possible dissection), or any chest pain in someone with known heart disease. Do not drive yourself. Emergency services can perform an ECG en route. Seek urgent evaluation (same-day, emergency department, or urgent care with ECG capability) for: new, unexplained chest pain lasting more than 15 minutes, chest pain with exertion that resolves with rest, or chest pain in a person with multiple cardiovascular risk factors. Routine appointment is appropriate for: reproducibly musculoskeletal chest wall pain with clear tenderness, known GI reflux with typical heartburn symptoms, or mild atypical symptoms in a low-risk young patient.

When to See a Doctor

New or unexplained chest discomfort — pressure, tightness, burning, or pain — always deserves evaluation, not self-reassurance. The stakes of a missed cardiac diagnosis are too high to tolerate diagnostic uncertainty without testing. JourneyDoctors connects you with trained specialists from $19. Start a consultation today — no waiting room, no referral needed.

Disclaimer: This article is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional for diagnosis and treatment. If you are currently experiencing chest pain, call 911 immediately.

Frequently Asked Questions

If my ECG is normal, does that mean my chest pain is not cardiac?

A normal ECG significantly reduces — but does not eliminate — the probability of cardiac chest pain. Approximately 6 percent of MIs present with a normal initial ECG, and non-STEMI can produce subtle or no ECG changes early in the event. This is why high-sensitivity troponin testing, typically drawn at presentation and one to three hours later, is combined with ECG in the evaluation. A normal ECG plus two normal high-sensitivity troponin values at 0 and 1 to 2 hours has a very high negative predictive value for ruling out NSTEMI and provides the basis for safe discharge protocols in low-risk patients.

Can chest pain be caused by stress alone?

Yes. Anxiety, panic disorder, and acute psychological stress all produce real physiological chest symptoms through the sympathetic nervous system — increased heart rate, palpitations, chest tightness, shortness of breath. These are not imagined. However, psychological chest pain should never be assumed until cardiac and other serious causes have been properly evaluated. Stress can also precipitate true cardiac ischemia in people with underlying coronary artery disease (Takotsubo cardiomyopathy, or stress cardiomyopathy, is a recognized syndrome). A psychiatric diagnosis of anxiety does not make someone immune to cardiac disease.

What does a heart attack feel like in a woman?

Women with MI more commonly experience shortness of breath, unusual fatigue (often days before the event), nausea or vomiting, back or jaw pain, and epigastric pressure rather than the classic crushing left chest pressure. Some women describe the sensation as a fullness, tightness, or uncomfortable pressure in the center of the chest. Many also have the classic presentation. The critical message is that the absence of "textbook" left chest pressure in a woman does not make chest symptoms less urgent — particularly if accompanied by dyspnea, diaphoresis, or cardiovascular risk factors.

Is it safe to take antacids for chest pain before seeing a doctor?

If you are having chest pain, taking an antacid will not make a cardiac emergency worse and may relieve GI-related symptoms, but it should not substitute for evaluation or delay care. If symptoms are severe, sudden, or accompanied by shortness of breath, sweating, arm or jaw pain, or dizziness — do not take antacids and wait. Call 911. If symptoms are mild, atypical, and have a clear post-meal pattern consistent with your known reflux history, antacid use while arranging a medical consultation is reasonable. When in doubt, err toward evaluation.

How do doctors tell the difference between a panic attack and a heart attack in the ER?

In the emergency department, the differentiation is made by combination of ECG, troponin, history, and imaging — not primarily by clinical impression. Panic attacks typically occur in younger patients, have identifiable precipitants, resolve within 20 to 30 minutes, and may have associated hyperventilation and perioral numbness. But clinically, panic attacks and MI overlap significantly enough that the AHA does not recommend diagnosis by history alone. Standard cardiac workup is performed on anyone with chest pain, regardless of suspicion for panic. Once cardiac and pulmonary causes are excluded, the clinical picture of panic disorder can be identified and addressed. This approach avoids the dangerous shortcut of dismissing cardiac symptoms in anxious patients.