Management of Acute Chest Pain: Step-by-Step Guideline-Based Approach
For any patient presenting with acute chest pain, obtain a 12-lead ECG within 10 minutes of arrival and immediately measure high-sensitivity cardiac troponin to identify life-threatening conditions requiring urgent intervention. 1, 2
Initial Assessment and Immediate Workup
First 10 Minutes
- Obtain 12-lead ECG within 10 minutes to identify STEMI requiring immediate reperfusion therapy 1, 2
- Measure high-sensitivity cardiac troponin (hs-cTn) at presentation (time 0) 1, 2
- Obtain vital signs including oxygen saturation 2
- Administer aspirin 162-325 mg immediately (chewed, non-enteric coated) unless contraindicated 2, 3
Within First Hour
- Obtain chest radiograph to evaluate for pneumonia, pneumothorax, aortic dissection, pleural effusion, and pulmonary edema 1
- Repeat hs-cTn at 1-2 hours if initial troponin is negative and clinical suspicion remains 1, 2
- Perform serial ECGs if initial tracing is nondiagnostic, especially with persistent symptoms 1, 2
- Consider supplemental leads V7-V9 in patients with intermediate-to-high ACS suspicion and nondiagnostic initial ECG to detect posterior MI 1, 2
Additional Laboratory Testing
- Do NOT order CK-MB or myoglobin as these are not useful when cardiac troponin is available 1
- Complete blood count and basic metabolic panel to assess for anemia, electrolyte abnormalities, and renal function 1
- D-dimer and CT pulmonary angiography if pulmonary embolism is suspected based on pretest probability 4, 1
- CT angiography of chest if aortic dissection is suspected 4, 1
- Blood cultures before antibiotics if endocarditis is suspected (fever with chest pain) 5
Risk Stratification
High-Risk Features (Proceed to Invasive Coronary Angiography)
Patients with any of the following require ICA 4, 2:
- New ischemic changes on ECG
- Troponin-confirmed acute myocardial injury
- New-onset left ventricular systolic dysfunction (ejection fraction <40%)
- Newly diagnosed moderate-severe ischemia on stress testing
- Hemodynamic instability
- High HEART score (7-10) or high TIMI score (5-7) 6
Low-Risk Criteria (Can Be Discharged)
Patients meeting ALL of the following can be discharged 4, 1:
- hs-cTn at time 0 below assay limit of detection OR "very low" threshold if symptoms present ≥3 hours
- hs-cTn at 1-2 hours with delta below assay "low" thresholds
- Low HEART score (0-3) or low TIMI score (0-1) 6
- <1% 30-day risk of death or MACE
Intermediate-Risk Patients
- Obtain transthoracic echocardiography (TTE) to assess ventricular function, wall motion abnormalities, valvular function, and pericardial effusion 1, 2
- Shared decision-making regarding admission versus observation versus outpatient evaluation 4
Immediate Medical Therapy
For All Patients With Suspected ACS
- Aspirin 162-325 mg (chewed, non-enteric coated) unless contraindicated 2, 3
- Sublingual nitroglycerin 0.3-0.4 mg every 5 minutes (up to 3 doses) for ongoing ischemic chest pain 2
- CRITICAL PITFALL: Do NOT give nitrates if patient used phosphodiesterase-5 inhibitors recently (risk of severe hypotension) 2
- Supplemental oxygen ONLY if arterial oxygen saturation <90%, respiratory distress, or high-risk features of hypoxemia 2
- Avoid NSAIDs for pain as they increase risk of major adverse cardiac events 2
Once ACS is Confirmed
- Dual antiplatelet therapy: Aspirin plus P2Y12 inhibitor (clopidogrel 300 mg loading dose then 75 mg daily, or more potent agent like ticagrelor or prasugrel) 2, 3
- Anticoagulation: Low molecular weight heparin, unfractionated heparin, bivalirudin, or fondaparinux 2, 3
- Statin therapy 3
- ACE inhibitor 3
- Beta blocker 3
- Proton pump inhibitor for patients at higher than average risk of GI bleeding 3
Advanced Imaging Based on Clinical Scenario
If Aortic Dissection Suspected
- CTA of chest, abdomen, and pelvis for diagnosis and treatment planning 4
If Pulmonary Embolism Suspected
- CTA using PE protocol in stable patients with high clinical suspicion 4
- Guide further testing by pretest probability 4
If Myopericarditis Suspected
- TTE to determine presence of ventricular dysfunction, pericardial effusion 4
- Cardiac MRI with gadolinium contrast is gold standard to distinguish myopericarditis from MINOCA, especially if diagnostic uncertainty exists 4, 5
If Nonischemic Cardiac Pathology Suspected
- TTE for suspected aortic pathology, pericardial effusion, or endocarditis 4
For Prior CABG Patients Without ACS
- Stress imaging to evaluate for myocardial ischemia OR CCTA for graft stenosis/occlusion 4
- ICA if stress test is indeterminate/nondiagnostic 4
For High-Risk Troponin-Positive Patients With Nonobstructive CAD
- CMR or echocardiography to establish alternative diagnoses 4
Critical Pitfalls to Avoid
- Never rely on single troponin when clinical suspicion is high—serial measurements at 1-2 hours are mandatory 1, 2
- Never delay transfer to ED for troponin testing in office-based patients with suspected ACS 1
- Maintain high suspicion in women and elderly who frequently present with atypical symptoms (dyspnea, fatigue, nausea) rather than classic chest pain 2
- Consider cocaine and methamphetamine use as potential causes in patients with acute chest pain 4
- Transfer patients on dialysis with acute unremitting chest pain by EMS to acute care setting 4
- Incorporate previous testing results when available into clinical decision-making 1
Disposition and Follow-Up
Low-Risk Patients
- Discharge home after appropriate troponin evaluation without admission or urgent cardiac testing 1
- Use patient decision aids to improve understanding and facilitate risk communication 4
Intermediate-Risk Patients
- Shared decision-making regarding admission, observation, discharge, or outpatient evaluation 4
- Stress testing (treadmill ECG or stress myocardial perfusion imaging) before discharge or within 72 hours if normal serial ECGs and troponins 2