What are the signs that chest pain is cardiac ischemia and requires emergency care?

Recognizing Cardiac Ischemia and When Chest Pain Requires Emergency Care

Call 9-1-1 immediately if chest pain is retrosternal discomfort (pressure, heaviness, tightness, squeezing) that builds over minutes, especially if accompanied by diaphoresis, dyspnea, nausea, or occurs at rest or with minimal exertion—these features strongly suggest acute coronary syndrome requiring emergency evaluation. 1

High-Risk Features Requiring Immediate Emergency Care

Classic Ischemic Chest Pain Characteristics

• Nature of discomfort: Retrosternal chest pressure, heaviness, tightness, constriction, or squeezing (not necessarily "pain") 1
• Onset pattern: Symptoms that gradually build in intensity over several minutes (not seconds) 1
• Radiation: Discomfort extending to shoulders, arms, jaw, neck, upper back, or upper abdomen 1

Critical Associated Symptoms Indicating Ischemia

• Autonomic symptoms: Diaphoresis, nausea, vomiting, or lightheadedness 1
• Respiratory symptoms: Dyspnea or shortness of breath 1
• Cardiovascular symptoms: Palpitations, presyncope, or syncope 1
• Gastrointestinal mimics: Upper abdominal pain or heartburn unrelated to meals 1

High-Risk Precipitating Factors

• Rest or minimal exertion: Anginal symptoms occurring at rest or with minimal activity strongly indicate acute coronary syndrome 1
• Exercise or emotional stress: Physical exertion or emotional stress triggering symptoms suggests cardiac ischemia 1

Physical Examination Findings Requiring Emergency Evaluation

Signs of Acute Coronary Syndrome

• Hemodynamic instability: Diaphoresis, tachypnea, tachycardia, or hypotension 1
• Heart failure signs: Pulmonary crackles, S3 gallop, or new mitral regurgitation murmur 1
• Note: Physical examination may be completely normal in uncomplicated acute coronary syndrome cases 1

Features LESS Likely to Represent Cardiac Ischemia

Characteristics Suggesting Non-Ischemic Causes

• Sharp, stabbing pain: Especially if it increases with inspiration or lying supine (suggests pericarditis or musculoskeletal) 1
• Fleeting pain: Discomfort lasting only seconds is unlikely ischemic 1
• Highly localized pain: Pain pinpointed to a very small area 1
• Positional pain: Discomfort that varies with body position suggests musculoskeletal origin 1
• Reproducible tenderness: Pain reproduced by palpation of chest wall or costochondral joints 1, 2
• Radiation below umbilicus: Pain extending below the umbilicus or to the hip is unlikely myocardial ischemia 1

Immediate Actions When Ischemia is Suspected

Prehospital Management

• Activate 9-1-1: Patients or bystanders should call emergency medical services for transport to the closest emergency department 1
• Avoid delayed transfer: Patients with suspected acute coronary syndrome initially evaluated in office settings must be transported urgently to the emergency department, ideally by EMS—delayed transfer for testing should be avoided 1

Emergency Department Evaluation Timeline

• ECG within 10 minutes: An electrocardiogram must be acquired and reviewed for ST-elevation myocardial infarction within 10 minutes of arrival for all patients with acute chest pain 1
• Immediate troponin measurement: Cardiac troponin should be measured as soon as possible after presentation in all patients with suspected acute coronary syndrome 1
• Serial ECGs: If the initial ECG is nondiagnostic but clinical suspicion remains high or symptoms persist, serial ECGs should be performed to detect evolving ischemic changes 1

Special Population Considerations

Women with Chest Pain

• Equal likelihood of chest pain: Women present with chest pain as commonly as men, but are more likely to have additional accompanying symptoms 1
• Multiple associated symptoms: Women more frequently report ≥3 associated symptoms including palpitations, jaw pain, neck pain, and back pain 1
• Risk of underdiagnosis: Women presenting with chest pain are at risk for underdiagnosis, and potential cardiac causes must always be considered 1

Older Patients (>75 Years)

• Atypical presentations: Acute coronary syndrome should be considered when accompanying symptoms include shortness of breath, syncope, acute delirium, or unexplained falls 1

Patients with Diabetes

• Atypical symptom patterns: Stabbing, sharp pain, or discomfort in the throat or abdomen may represent ischemia in diabetic patients 1

Common Pitfalls to Avoid

Misleading Clinical Features

• Nitroglycerin response: Relief with nitroglycerin is NOT diagnostic of myocardial ischemia and should not be used as a diagnostic criterion 1
• Normal examination: A completely normal physical examination does not exclude acute coronary syndrome 1

Life-Threatening Mimics Requiring Emergency Care

• Aortic dissection: Sudden onset "worst chest pain of my life" with ripping quality, especially with radiation to upper or lower back, pulse differential, or in hypertensive patients 1
• Pulmonary embolism: Tachycardia plus dyspnea (present in >90% of patients) with pleuritic chest pain 1