What is the initial management for an adult patient with a history of cardiovascular disease presenting with chest pain?

Initial Management of Chest Pain in Adults with Cardiovascular Disease

For an adult with cardiovascular disease presenting with chest pain, immediately call 9-1-1 for emergency transport, obtain a 12-lead ECG within 5-10 minutes, administer aspirin 160-325 mg (chewed) unless contraindicated, and initiate continuous cardiac monitoring while rapidly excluding life-threatening causes. 1, 2

Immediate Actions (First 10 Minutes)

Emergency Medical Services Activation

• Call 9-1-1 immediately rather than attempting office-based evaluation or self-transport, as EMS allows for intervention if complications occur en route and reduces mortality through earlier treatment 1
• Transport to a facility with coronary care unit or chest pain unit capabilities without delay, as rapid availability of reperfusion therapy is associated with 53% reduction in mortality 3

Rapid ECG Acquisition

• Obtain 12-lead ECG within 5-10 minutes of first patient contact to identify ST-segment elevation myocardial infarction (STEMI), ST-segment depression, T-wave inversions, new Q waves, or new left bundle branch block 3, 1, 2
• Compare with previous ECG if available, particularly valuable in patients with pre-existing cardiac pathology such as left ventricular hypertrophy 2
• Initiate continuous multi-lead ECG monitoring for arrhythmias and dynamic ST-segment changes 2, 4

Immediate Pharmacotherapy

• Administer aspirin 160-325 mg (chewed, not swallowed) as soon as possible unless contraindicated by known allergy or active gastrointestinal bleeding 1
• Provide pain relief and correct hemodynamic changes without delay 3
• Administer sublingual nitroglycerin for symptom relief, but do not use nitroglycerin response as a diagnostic tool for ACS, as esophageal spasm and other conditions may also respond 1

Risk Stratification Framework

High-Risk Features Requiring Immediate Hospital Transfer

• Prolonged ongoing rest pain (>20 minutes) with associated diaphoresis, dyspnea, nausea, or syncope 1
• Severe continuing pain with ischemic ECG changes 3
• Left ventricular failure or other hemodynamic abnormalities 3
• New or dynamic ST-segment changes on ECG 3
• Patients with extensive prior cardiac surgery, prosthetic valves, and pacemaker dependency are automatically considered high-risk 4

Intermediate-Risk Features

• Prior history of myocardial infarction or known coronary artery disease 1
• Age >70 years 1
• Diabetes mellitus or renal insufficiency 1

Diagnostic Testing Algorithm

Laboratory Assessment

• Draw cardiac troponin T or I immediately on admission as the preferred marker of myocardial damage 2
• Repeat troponin measurement at 10-12 hours after symptom onset for diagnosis of possible myocardial infarction and risk assessment 3, 2
• Blood samples should be drawn for CK-MB mass and troponin on admission and at 10-12 hours after the beginning of chest pain 3
• Do not delay transfer to emergency department for troponin testing in office settings when ACS is suspected 1, 5

Focused History Elements

• Document specific chest pain characteristics: quality (squeezing, grip-like, suffocating, heavy), location, severity, duration, radiation (neck, lower jaw, left arm), associated symptoms, precipitating factors, and relieving factors 3, 2
• Sharp chest pain that increases with inspiration and lying supine is unlikely ischemic and suggests pericarditis 2
• Chest pain that radiates to one or both shoulders/arms or is precipitated by exertion increases likelihood of ACS (likelihood ratios 2.3-4.7) 6
• Pain that is stabbing, pleuritic, positional, or reproducible by palpation decreases likelihood of ACS (likelihood ratios 0.2-0.3) 6

Physical Examination Priorities

• Assess for hemodynamic instability including hypotension, pulmonary rales, new murmurs, and signs of cardiogenic shock 4
• Examine for pulse differentials between extremities to suggest aortic dissection 4
• Evaluate for autonomic nervous system activation (pallor, sweating), irregularities of pulse, bradycardia or tachycardia, third heart sound, and basal rales 3
• Perform focused cardiovascular examination evaluating for valvular heart disease, hypertrophic cardiomyopathy, and heart failure signs 2

Disposition and Treatment Decisions

STEMI Management

• If ST-segment elevation indicates evolving Q wave infarction, thrombolytic treatment should be started within 30 minutes 3
• Primary percutaneous coronary intervention (PCI) is preferred with door-to-balloon time <90 minutes, or fibrinolytic therapy with door-to-needle time <30 minutes 1
• Age-adjusted 30-day mortality of patients treated in coronary care units is 6.8%, compared to 10.9% in general internal medicine wards 3

NSTEMI/Unstable Angina Management

• If acute coronary syndrome is suspected, aspirin should be given as soon as possible and low-molecular-weight heparin can be started in the emergency department 3
• Admit to coronary care unit with continuous cardiac monitoring for elevated troponin without ST-elevation 1
• Priority should be given to those at highest risk when there is shortage of coronary care unit beds 3
• Administer beta-blocker unless contraindicated, and provide oral or intravenous nitrates for persistent or recurrent symptoms 2

Observation Period for Unclear Cases

• Most patients can be better evaluated in chest pain units than in the emergency department for 10-12 hours after the beginning of symptoms 3
• Recurrent ischemia, elevated troponin levels, and hemodynamic instability during the 8-12 hour observation period are high-risk features requiring aggressive management 2
• Repeat troponin measurement at 3,6, and 9-12 hours after symptom onset to detect delayed rise indicating myocardial injury 4
• Perform serial ECGs at scheduled intervals (every 2-4 hours) to detect evolving ischemic changes 4

Alternative Life-Threatening Diagnoses to Exclude

When ECG is Normal

• A careful history, clinical examination, and laboratory examinations are needed when the ECG is normal but the patient has severe chest pain 3
• Pulmonary embolism, aortic dissection, acute pericarditis, and pneumothorax are rare compared to acute coronary syndromes but are all life-threatening conditions 3
• Obtain chest radiograph to evaluate for pulmonary venous congestion, cardiomegaly, pneumonia, pneumothorax, and pleural effusion 2

Specific Presentations

• Aortic dissection is characterized by sudden onset ripping chest pain with radiation to back; evaluate for pulse differential and mediastinal widening on chest radiograph 2
• Pneumothorax presents with acute chest pain and dyspnea 2
• Acute pericarditis is characterized by sharp pain increased with inspiration and lying supine 2

Special Population Considerations

Women

• Women are at risk for underdiagnosis of ACS and may present with accompanying symptoms such as nausea, fatigue, shortness of breath, arm pain, jaw pain, and epigastric discomfort rather than classic chest pain 1

Elderly Patients (≥75 years)

• Elderly patients may present with atypical symptoms including isolated dyspnea, syncope, acute delirium, or unexplained falls without classic chest pain 1
• Other presentations such as fatigue, dyspnea, faintness, or syncope are common in the elderly 3

Patients with Prior Cardiac Surgery

• Patients with extensive prior cardiac surgery, prosthetic valves, and pacemaker dependency require aggressive evaluation even with minimal symptoms 4
• Prosthetic valve complications such as thrombosis, dehiscence, or endocarditis can present with chest pain and catastrophic hemodynamic collapse 4

Critical Pitfalls to Avoid

• Do not assume young age excludes ACS, as it can occur in adolescents without traditional risk factors 1
• Atypical presentations are common, particularly in older patients, women, and those with diabetes 2
• The risk of patients discharged without correctly diagnosing acute coronary syndrome is high without proper observation; without aspirin and heparin, 20-30% of patients with unstable angina either died or had myocardial infarction within 4 weeks 3
• Do not use nitroglycerin response as a diagnostic tool for ACS 1
• Palpating the chest wall to determine if pain is reproducible does not exclude cardiac causes 4
• Five-day duration of symptoms does not exclude acute coronary syndrome, as unstable angina can present with prolonged or recurrent symptoms 2