What is the initial management of chest pain?

Initial Management of Chest Pain

All patients presenting with chest pain should receive a 12-lead ECG within 10 minutes of arrival, immediate cardiac monitoring, and aspirin 250-500mg (unless contraindicated) while simultaneously assessing for life-threatening conditions. 1, 2

Immediate Actions (First 5-10 Minutes)

Stabilization and Monitoring

• Place patient on continuous cardiac monitoring with defibrillator patches or equipment immediately available 1, 3
• Obtain vital signs including blood pressure in both arms (>20 mmHg difference suggests aortic dissection) 1
• Position patient sitting or semi-recumbent to minimize risk of hypotension 4
• Establish IV access 1

ECG Acquisition

• Obtain and interpret 12-lead ECG within 10 minutes of presentation 1, 2, 3
• This is a Class I recommendation and the single most critical diagnostic step 1
• ECG interpretation determines immediate management pathway (STEMI vs NSTE-ACS vs other) 1

Initial Pharmacotherapy

Aspirin Administration:

• Give aspirin 250-500mg immediately if acute coronary syndrome suspected and no contraindications 1, 2
• Early aspirin (within 2 hours) improves survival at 7 days, 30 days, and 1 year compared to delayed administration 5
• Do not delay aspirin for ECG results in suspected ACS 1, 2

Pain Relief:

• Administer sublingual nitroglycerin 0.4mg for ongoing chest pain (repeat every 5 minutes up to 3 doses) 1, 4
• Critical caveat: Nitroglycerin is contraindicated if systolic BP <90 mmHg, bradycardia, or if patient has used phosphodiesterase-5 inhibitors (sildenafil, tadalafil, vardenafil) within 24-48 hours 4
• Note that nitroglycerin response does NOT distinguish cardiac from non-cardiac chest pain (sensitivity 72%, specificity 37%) 6
• Consider IV morphine for severe pain unrelieved by nitroglycerin, titrated to effect 1

Risk Stratification Based on ECG Findings

ST-Elevation Myocardial Infarction (STEMI)

• Initiate reperfusion therapy within 30 minutes (door-to-needle time for thrombolysis or door-to-balloon time for PCI) 1
• Transfer immediately to facility with 24/7 interventional cardiology capability 1, 3
• Add P2Y12 inhibitor (ticagrelor or clopidogrel loading dose) and anticoagulation (enoxaparin or UFH) 1

NSTE-ACS (ST-Depression or Dynamic T-Wave Changes)

• Draw cardiac troponin (preferably high-sensitivity) on arrival and repeat at 1-3 hours 1
• Results must be available within 60 minutes 1
• Add anticoagulation (enoxaparin or UFH) and P2Y12 inhibitor if high-risk features present 1
• High-risk features requiring immediate invasive strategy: ongoing chest pain >20 minutes, hemodynamic instability, life-threatening arrhythmias, cardiogenic shock, acute heart failure 1, 3

Normal or Non-Diagnostic ECG

• Do NOT discharge based on normal ECG alone 1
• Obtain serial troponins at admission and 10-12 hours after symptom onset 1
• Consider observation in chest pain unit for 10-12 hours 1
• Evaluate for non-ACS life-threatening causes 1

Critical Differential Diagnoses to Exclude

Aortic Dissection

• Suspect if: abrupt/instantaneous onset, ripping/tearing quality pain, pulse deficit, BP differential >20 mmHg between arms, new aortic regurgitation murmur, focal neurologic deficit 1
• Do NOT give aspirin or anticoagulation if dissection suspected 1
• Obtain immediate CT angiography or transesophageal echocardiography 1

Pulmonary Embolism

• Consider in patients with dyspnea, pleuritic chest pain, risk factors for venous thromboembolism 1, 3
• Obtain D-dimer, chest CT angiography, or V/Q scan 1

Tension Pneumothorax

• Suspect if sudden onset, unilateral decreased breath sounds, tracheal deviation, hypotension 1, 7
• Requires immediate needle decompression 7

Pericarditis

• Characterized by sharp, positional pain relieved by sitting forward 1, 3
• ECG shows diffuse ST elevation with PR depression 1

Additional Diagnostic Work-Up

Laboratory Tests

• Obtain on arrival: high-sensitivity troponin, complete blood count, creatinine, glucose, lipid panel 1
• Repeat troponin at appropriate intervals based on assay type (1-3 hours for high-sensitivity) 1

Imaging

• Chest X-ray for all patients to evaluate for pneumothorax, pneumonia, heart failure, widened mediastinum 1
• Consider bedside echocardiography if hemodynamic instability or new murmur detected 1

Disposition Decisions

Admit to CCU/ICU

• STEMI or high-risk NSTE-ACS 1
• Hemodynamic instability, cardiogenic shock, acute heart failure 1
• Life-threatening arrhythmias 1
• Confirmed aortic dissection, massive PE, tension pneumothorax 1

Admit to Chest Pain Unit/Telemetry

• NSTE-ACS without high-risk features 1
• Troponin-negative patients with intermediate risk requiring serial testing 1

Consider Discharge

• Only after: normal ECG, negative serial troponins at appropriate intervals (including 10-12 hours post-symptom onset), no high-risk features, alternative non-cardiac diagnosis established 1
• Low-risk patients may be discharged after 24-48 hours if they remain asymptomatic 1

Critical Pitfalls to Avoid

• Never delay aspirin or reperfusion therapy while awaiting consultation or additional testing in suspected ACS 2, 3
• Do not rely on pain severity to determine urgency—severity poorly predicts cardiac arrest risk 2
• Atypical presentations are common in elderly, diabetic patients, and women (dyspnea, fatigue, nausea without chest pain) 1, 2, 3
• Nitroglycerin response does not confirm or exclude cardiac etiology 6
• Never discharge patients with normal initial troponin if presenting within 6 hours of symptom onset—serial testing mandatory 1
• Physical examination contributes minimally to MI diagnosis unless shock present 2
• Beta-blockers are effective for pain relief in tachycardic, hypertensive patients with suspected ischemia 1