Differential Diagnosis for Chest Pain

Life-Threatening Causes

• The American College of Cardiology recommends immediate identification of life-threatening conditions such as acute coronary syndrome (ACS), aortic dissection, pulmonary embolism, tension pneumothorax, and esophageal rupture, which can present with retrosternal pressure-type discomfort, sudden-onset "ripping" or "tearing" chest pain, acute dyspnea, or severe dyspnea with unilateral absence of breath sounds 1, 2
• Acute Coronary Syndrome (STEMI/NSTEMI/Unstable Angina) is characterized by retrosternal pressure-type discomfort building gradually over minutes, radiating to left arm/jaw/neck, associated with diaphoresis, dyspnea, nausea, or syncope, and may occur at rest or with minimal exertion 1, 2, 3
• Aortic Dissection presents with sudden-onset "ripping" or "tearing" chest pain, radiating to upper or lower back, with pulse differentials between extremities, blood pressure differentials, or new aortic regurgitation murmur 1, 4
• Pulmonary Embolism is characterized by acute dyspnea with pleuritic chest pain, tachycardia present in >90% of patients, tachypnea, and associated risk factors 1, 4

Serious But Non-Immediately Fatal Causes

• Pericarditis is characterized by sharp, pleuritic chest pain that worsens when supine and improves when leaning forward, friction rub on examination, and fever 1, 4
• Myocarditis presents with chest pain, fever, signs of heart failure, and S3 gallop 4
• Valvular Disease, such as aortic stenosis, aortic regurgitation, and hypertrophic cardiomyopathy, can cause chest pain and should be considered in the differential diagnosis 4

Common Benign Causes

• Costochondritis/Tietze Syndrome is characterized by tenderness of costochondral joints on palpation and pain reproducible with chest wall pressure 4, 5
• Chest Wall Pain is localized to a very limited area, affected by palpation, breathing, turning, twisting, or bending 1, 6
• Gastroesophageal Reflux Disease/Esophagitis presents with burning retrosternal pain related to meals, relieved by antacids 4, 5

Critical Historical Features to Distinguish Causes

• Gradual onset of chest pain over minutes, retrosternal pressure/heaviness/squeezing quality, radiation to left arm, neck, jaw, and precipitation by exertion or emotional stress are characteristic of Acute Coronary Syndrome 1, 3
• Sharp pain increasing with inspiration and lying supine, fleeting pain lasting only seconds, and pain localized to a very small area or radiating below umbilicus are suggestive of non-ischemic etiology 1

High-Risk Features Requiring Immediate Action

• Age >75 years with accompanying dyspnea, syncope, acute delirium, or unexplained fall, women presenting with atypical symptoms, and patients with diabetes, renal insufficiency, or dementia require immediate attention 3, 4

Common Pitfalls

• The American College of Cardiology recommends against using nitroglycerin response as a diagnostic criterion, as esophageal spasm and other conditions also respond to nitroglycerin 1, 2
• The American Heart Association advises against dismissing chest pain in women or elderly patients, as they frequently present with atypical symptoms 3, 4

Evaluating Chest Pain

Essential Pain Characteristics

• The American Heart Association recommends asking about the exact location of pain and where it radiates to determine whether urgent transfer to the emergency department is required 7
• Chest pain encompasses discomfort in shoulders, arms, neck, back, upper abdomen, or jaw—not just the chest itself, according to the American College of Cardiology 8, 9

Critical Associated Symptoms

• The American Heart Association suggests that accompanying symptoms such as diaphoresis, dyspnea, nausea, syncope, or palpitations significantly increase the likelihood of acute coronary syndrome 8
• Women may be more likely to present with nausea and shortness of breath alongside chest pain, as noted by the American College of Cardiology 8, 9

High-Risk Features Requiring Immediate Action

• The American Heart Association recommends that presentations with clinical evidence of acute coronary syndrome or other life-threatening causes mandate urgent transfer to the emergency department by EMS, not personal automobile 7
• Hemodynamic instability requires immediate action, according to the American College of Cardiology 7

Medication History

• The American Heart Association recommends documenting current medications, particularly anticoagulants, antiplatelet agents, and erectile dysfunction drugs, to inform treatment decisions 7

Differential Diagnoses for Stabbing Chest Pain

Diagnostic Considerations

• The European Society of Cardiology recommends considering costochondritis as a prevalent diagnosis in chest pain presentations, accounting for the majority of cases when cardiac causes are excluded, characterized by tenderness of costochondral joints on palpation, pain reproducible with chest wall pressure, and pain affected by palpation, breathing, turning, twisting, or bending 10
• The American Heart Association suggests that an ECG should be obtained immediately, even in the outpatient setting with chronic symptoms, unless a clearly non-cardiac cause is evident, and if unavailable, refer to the emergency department 11
• The European Society of Cardiology recommends checking cardiac troponin if any concern for Acute Coronary Syndrome (ACS) exists, though less likely with chronic stabbing pain, and measuring high-sensitivity cardiac troponin if the patient has risk factors or any atypical features 12, 11

Management and Triage

• The American Heart Association advises transferring patients urgently to the emergency department by EMS if high-risk features are present, including new ECG abnormalities, and not to delay transfer for troponin testing in the office setting 11, 12
• A management algorithm is suggested, which includes obtaining an ECG within 10 minutes, and if ECG shows ST elevation or new ischemic changes, immediate transfer by EMS is required 11, 12

Diagnostic Approach to Pleuritic Chest Pain

Initial Evaluation

• The American College of Cardiology suggests that a clinical presentation of pleuritic chest pain worsening with deep breathing, coughing, and lying down strongly suggests pericarditis, but life-threatening conditions must be excluded first 13
• The European Heart Journal recommends using D-dimer levels to help exclude aortic dissection and pulmonary embolism, with levels <500 ng/mL making these conditions unlikely 14
• Repeat vital signs, including oxygen saturation and blood pressure in both arms, are necessary to detect pulse/BP differentials suggestive of aortic dissection 14

Diagnostic Criteria for Pericarditis

• The American College of Cardiology states that sharp, pleuritic chest pain that worsens with inspiration and coughing is a classic presentation for acute pericarditis 13
• Pain that is positional (worse lying down) and worsens with burping suggests esophageal/pericardial involvement rather than myocardial ischemia 13

Exclusion of Life-Threatening Causes

• The American College of Cardiology and European Heart Journal suggest that acute coronary syndrome is unlikely if the pain is sharp and pleuritic, positional, and worsens with burping 13
• Aortic dissection is unlikely if there is no sudden-onset "ripping" or "tearing" quality, normal vital signs without pulse differentials or BP discrepancies, and gradual onset over 3 days 13, 14

Management of Acute Pericarditis

• The European Heart Journal recommends initiating anti-inflammatory therapy with ibuprofen 600-800mg TID for 1-2 weeks or colchicine 0.6mg BID for 3 months 14
• The American College of Cardiology advises against using nitroglycerin response as a diagnostic test, as it relieves esophageal spasm and other noncardiac conditions 13

Chest Pain Worsening When Lying Supine: Pericarditis Until Proven Otherwise

Immediate Life-Threatening Exclusions Required

• The American College of Cardiology recommends that an ECG must be acquired and interpreted within 10 minutes of patient arrival regardless of setting 15, 16, 17
• The American Heart Association suggests that if ST-elevation or new ischemic changes are present, treat as STEMI immediately and transport by EMS 16, 18, 19
• The American College of Cardiology states that cardiac troponin should be measured as soon as possible in all patients with acute chest pain and any suspicion of ACS 16, 17, 20

Clinical Features Distinguishing Pericarditis

• The American Heart Association notes that sharp, pleuritic chest pain that increases in the supine position and improves when leaning forward is the hallmark of pericarditis 15, 21, 22
• The American College of Cardiology recommends that sharp chest pain that increases with inspiration and lying supine is unlikely related to ischemic heart disease 23, 24, 20

Algorithmic Approach to This Patient

• The American College of Cardiology suggests that if the patient has clinical evidence of ACS or other life-threatening causes, transport urgently to the ED by EMS 21, 16, 17
• The American Heart Association recommends that high-risk features requiring immediate transfer include hemodynamic instability, associated diaphoresis, dyspnea, nausea, syncope, age >75 years with accompanying symptoms, or ECG abnormalities 18

Critical Pitfalls to Avoid

• The American College of Cardiology states that relief with nitroglycerin is not diagnostic of myocardial ischemia and should not be used as a diagnostic criterion 23
• The American Heart Association notes that women, elderly patients, and those with diabetes may present with atypical symptoms including sharp or stabbing pain 23, 24
• The American College of Cardiology recommends that for patients with acute chest pain and suspected ACS initially evaluated in the office setting, delayed transfer to the ED for troponin or other diagnostic testing should be avoided 16, 17, 20

Differential Diagnosis for Chest Pain in Adults

Prevalence of Chest Pain Causes

• Acute coronary syndrome accounts for 20% of chest pain in general practice and 45-60% in emergency settings, while musculoskeletal causes account for 43% of chest pain in general practice, and psychiatric causes account for 11% in general practice and 8% in emergency departments, according to the European Heart Journal 25

Common Causes of Chest Pain

• Musculoskeletal causes, such as costochondritis, account for a significant portion of chest pain cases, with a prevalence of 43% in general practice, as reported by the European Heart Journal 25
• Psychiatric causes, including anxiety and depression, are associated with 11% of chest pain cases in general practice and 8% in emergency departments, as noted in the European Heart Journal 25

Diagnostic Approach to Pleuritic Chest Pain with a Normal Electrocardiogram

Exclusion of Acute Coronary Syndrome (ACS)

Role of Troponin Testing

Consideration of Pericarditis

Imaging Findings Unrelated to Current Pain

Epidemiology of Costochondritis

Clinical Pitfalls

Evaluation and Management of Chest Pain with Suspected Costochondritis

Diagnostic Features Suggesting Musculoskeletal Origin

Immediate Evaluation to Exclude Life‑Threatening Cardiac Causes

Risk Stratification When ECG and Troponin Are Normal

Key Pitfalls to Avoid

Management Algorithm (Evidence‑Based Steps)

Treatment of Confirmed Costochondritis

Evaluation of Non‑Acute Coronary Syndrome Chest Pain (ACC Evidence)

Life‑Threatening Causes That Must Still Be Excluded

• Pulmonary embolism typically presents with sudden dyspnea and pleuritic chest pain; tachycardia occurs in >90 % of patients and risk factors for thromboembolism are common. – American College of Cardiology 36

• Pneumonia may cause localized pleuritic chest pain together with fever, productive cough, and egophony; diagnosis is confirmed by chest radiography. – American College of Cardiology 36

• Pleuritis produces sharp chest pain that worsens with deep inspiration. – American College of Cardiology 36

• Pneumothorax presents with pleuritic chest pain and unilateral reduction or absence of breath sounds. – American College of Cardiology 36

• Herpes zoster can mimic chest pain before the characteristic dermatomal rash appears. – American College of Cardiology 36

• Acute chest syndrome in sickle‑cell disease requires urgent evaluation because it can be life‑threatening. – American College of Cardiology 36

Musculoskeletal Causes

• Costochondritis/Tietze syndrome is identified by tenderness over costochondral joints; pain is reproduced by direct pressure and is influenced by breathing, turning, twisting, or bending of the torso. – American College of Cardiology 37

Gastro‑intestinal Causes

• Overall prevalence: gastrointestinal disorders account for 10–20 % of chest‑pain presentations in outpatient settings. – American College of Cardiology 37

• Gastro‑esophageal reflux disease (GERD) is the most frequent esophageal cause, producing burning retrosternal pain after meals or at night, worsened by stress and often relieved by antacids. – American College of Cardiology 37

• Esophageal motility disorders (e.g., achalasia, distal esophageal spasm, nutcracker esophagus) generate squeezing retrosternal pain or spasm, frequently accompanied by dysphagia. – American College of Cardiology 37

• Peptic ulcer disease can manifest as epigastric pain that radiates to the chest. – American College of Cardiology 36

• Esophagitis secondary to medications (NSAIDs, potassium, iron, bisphosphonates), infections, or eosinophilic inflammation may mimic cardiac chest pain. – American College of Cardiology 37

Cardiac Causes Other Than ACS

• Pericarditis presents with sharp, pleuritic chest pain that worsens when supine and improves when leaning forward, often accompanied by a pericardial friction rub and fever. – American College of Cardiology 37

Psychiatric Causes

• Panic disorder and anxiety are frequently associated with chest pain together with dyspnea, palpitations, and diaphoresis. – American College of Cardiology 36

Diagnostic Algorithm After ACS Exclusion

• Systematic approach: once ACS is ruled out by negative cardiac biomarkers and appropriate testing, clinicians should follow a stepwise evaluation. – American College of Cardiology 37

• Pain‑characteristic clues:

• Targeted physical examination: assess for chest‑wall tenderness (costochondritis), pericardial friction rub (pericarditis), unilateral breath sounds (pneumothorax), and pulse/BP differentials (aortic dissection). – American College of Cardiology 37

• Chest radiography is recommended when pulmonary etiologies are suspected or when the diagnosis remains uncertain. – American College of Cardiology 36

• Empiric proton‑pump inhibitor (PPI) trial for suspected GERD is reasonable; in one study PPIs were prescribed in only ~20 % of appropriate cases. – American College of Cardiology 37

• Further gastrointestinal work‑up (upper endoscopy, esophageal function testing, pH monitoring) is appropriate for recurrent unexplained chest pain. – American College of Cardiology 37

Critical Pitfalls to Avoid

• Nitroglycerin response is not diagnostic; esophageal spasm and other non‑cardiac conditions may also improve with nitroglycerin. – American College of Cardiology 37

• Do not dismiss chest pain in women, older adults, or patients with diabetes, as they often present with atypical symptoms. – American College of Cardiology 36

Immediate Identification and Management of Life‑Threatening Chest Pain in Adults

Life‑Threatening Causes Requiring Rapid Exclusion

Acute Coronary Syndrome (ACS)

• The initial assessment must promptly identify or rule out ACS, aortic dissection, pulmonary embolism, tension pneumothorax, and esophageal rupture because any of these can rapidly progress to death without urgent treatment. AHA/ACC guideline. 38
• Typical ACS pain is described as retrosternal pressure, heaviness, or squeezing that builds over minutes (not seconds) and may radiate to the left arm, jaw, or neck. AHA/ACC guideline. 39
• Frequently associated symptoms include diaphoresis, dyspnea, nausea, or syncope. AHA/ACC guideline. 38
• Physical examination may reveal tachycardia, hypotension, pulmonary crackles, an S3 gallop, or a new murmur of mitral regurgitation, but a completely normal exam does not exclude uncomplicated myocardial infarction. AHA/ACC guideline. 39

Aortic Dissection

• Sudden “ripping” or “tearing” chest or back pain that is maximal at onset is characteristic of aortic dissection. AHA/ACC guideline. 38
• A pulse differential between extremities occurs in ≈30 % of patients and is more common in type A dissections. AHA/ACC guideline. 39
• A systolic blood‑pressure difference > 20 mm Hg between the arms strongly suggests dissection. AHA/ACC guideline. 38
• A new aortic‑regurgitation murmur is present in 40‑75 % of type A dissections. AHA/ACC guideline. 39
• Underlying connective‑tissue disorders (e.g., Marfan syndrome) increase the risk of dissection. AHA/ACC guideline. 38
• The combination of severe abrupt pain, pulse differential, and a widened mediastinum on chest X‑ray confers > 80 % probability of dissection. AHA/ACC guideline. 38

Pulmonary Embolism (PE)

• Acute dyspnea accompanied by pleuritic chest pain is a hallmark presentation of PE. AHA/ACC guideline. 39
• Tachycardia is observed in > 90 % of patients with PE. AHA/ACC guideline. 38
• Chest pain typically worsens with inspiration (pleuritic character). AHA/ACC guideline. 39

Tension Pneumothorax

• Presents with dyspnea and sharp chest pain that intensifies on inspiration. AHA/ACC guideline. 38
• Physical exam shows unilateral absence or marked reduction of breath sounds. AHA/ACC guideline. 39
• Hemodynamic instability (e.g., hypotension, tachycardia) indicates tension physiology. AHA/ACC guideline. 38

Esophageal Rupture (Boerhaave Syndrome)

• Typically follows a bout of forceful emesis. AHA/ACC guideline. 39
• Subcutaneous emphysema on neck or chest examination is a key finding. AHA/ACC guideline. 38
• A concurrent pneumothorax occurs in about 20 % of cases. AHA/ACC guideline. 38
• A painful, tympanic abdomen may signal a life‑threatening gastrointestinal source. AHA/ACC guideline. 39

Serious Cardiac Causes (Non‑ACS)

Pericarditis

• Sharp, pleuritic chest pain that worsens when lying supine and improves when leaning forward is the classic presentation. AHA/ACC guideline. 39
• A pericardial friction rub may be heard on auscultation (absence does not exclude disease). AHA/ACC guideline. 38
• Fever is a common accompanying symptom. AHA/ACC guideline. 39

Myocarditis

• Presents with chest pain and fever; may also show signs of heart failure such as an S3 gallop. AHA/ACC guideline. 38
• Because clinical presentation mimics ACS, measurement of cardiac troponin is required for differentiation. AHA/ACC guideline. 38

Valvular Heart Disease

• Aortic stenosis: systolic murmur with delayed or diminished carotid pulse (pulsus tardus/parvus). AHA/ACC guideline. 39
• Aortic regurgitation: early diastolic murmur at the right sternal border with a rapid carotid upstroke. AHA/ACC guideline. 38
• Hypertrophic cardiomyopathy: displaced left‑ventricular impulse, prominent “a” wave in jugular venous pressure, and a systolic murmur that increases with Valsalva. AHA/ACC guideline. 39

Pulmonary and Infectious Causes

Pneumonia

• Fever together with localized, often pleuritic chest pain suggests pneumonia. AHA/ACC guideline. 38
• Physical findings may include regional dullness to percussion, egophony, or a pleural friction rub. AHA/ACC guideline. 39

Gastro‑intestinal Causes

Peptic Ulcer Disease

• Epigastric tenderness on examination supports peptic ulcer disease as a source of chest discomfort. AHA/ACC guideline. 38

Gallbladder Disease

• Right‑upper‑quadrant tenderness with a positive Murphy sign indicates biliary pathology that can refer pain to the chest. AHA/ACC guideline. 38

Esophageal Motility Disorders

• Esophageal spasm may relieve with nitroglycerin; therefore, nitroglycerin response should not be used to differentiate cardiac from esophageal chest pain. AHA/ACC guideline. 39

Musculoskeletal Causes

Costochondritis / Tietze Syndrome

• Palpable tenderness over costochondral joints is characteristic. AHA/ACC guideline. 38
• Presence of chest wall tenderness markedly reduces the probability of ACS, though it does not completely exclude it. AHA/ACC guideline. 39

Dermatologic Causes

Herpes Zoster

• Dermatomal pain triggered by light touch, followed by a unilateral vesicular rash, is diagnostic of herpes zoster. AHA/ACC guideline. 38

Immediate Diagnostic Actions (First 10 minutes)

• Obtain a 12‑lead ECG within 10 minutes of presentation. AHA/ACC guideline. 38
• Measure high‑sensitivity cardiac troponin immediately when ACS is suspected. AHA/ACC guideline. 39
• Perform a focused cardiovascular exam assessing pulse and blood‑pressure differentials between arms, new murmurs, pericardial rubs, and unilateral breath sounds. AHA/ACC guideline. 38

High‑Risk Features Prompting Immediate EMS Transport

• ST‑segment elevation or new ischemic changes on ECG. AHA/ACC guideline. 39
• Hemodynamic instability (e.g., hypotension, shock). AHA/ACC guideline. 38

Clinical Pitfalls to Avoid

• Do not rely on nitroglycerin response to distinguish cardiac from non‑cardiac chest pain, as esophageal spasm and other conditions may also improve. AHA/ACC guideline. 38
• Do not dismiss chest pain in women, elderly patients, or individuals with diabetes based on atypical presentations. AHA/ACC guideline. 38
• Do not assume a normal physical examination excludes ACS; uncomplicated myocardial infarction can present with a completely normal exam. AHA/ACC guideline. 39

Acute Chest Pain Evaluation and Immediate Management in Young Adults

1. Initial Diagnostic Evaluation

• Obtain a 12‑lead ECG within 10 minutes of arrival and draw a high‑sensitivity cardiac troponin (hs‑cTn) immediately; repeat hs‑cTn at 3–6 hours to safely exclude acute coronary syndrome (ACS) before attributing pain to musculoskeletal causes. (American College of Cardiology/American Heart Association guideline) [40][41]

• Measure hs‑cTn immediately; it is the most sensitive and specific biomarker for myocardial injury. (ACC/AHA & European Society of Cardiology) [40][41]42

• Morbid obesity markedly raises the pre‑test probability of coronary artery disease even in a 36‑year‑old patient. (European Society of Cardiology) [42][41]

• Radiation of chest pain to the left shoulder, arm, neck, or jaw is a classic pattern that substantially increases the likelihood of ACS. (ESC) 42

• Sudden worsening of pain with cold exposure can provoke coronary vasospasm and unmask underlying ischemia. (ESC) 42

• Associated light‑headedness suggests possible hemodynamic compromise and should raise concern for ACS. (ESC) 42

2. Electrocardiographic Strategy

• Interpret the initial ECG for ST‑elevation, ST‑depression, T‑wave inversion, or other acute ischemic changes. (ACC/AHA) [40][41]

• If the first ECG is nondiagnostic but suspicion remains high, obtain serial ECGs every 15–30 minutes to capture evolving ischemic patterns. (ACC/AHA) [40][41]

• Add posterior leads (V7–V9) when intermediate‑to‑high suspicion for ACS exists and the standard ECG is nondiagnostic, to detect posterior myocardial infarction. (ACC/AHA) [40][41]

• A normal initial ECG does not exclude ACS; 30–40 % of acute myocardial infarctions present with a normal or nondiagnostic ECG, and ≈5 % of ACS patients have a normal first ECG. (ESC) 42

3. Cardiac Biomarker Strategy

• A single normal hs‑cTn does not rule out ACS; serial measurements are required to improve diagnostic accuracy. (ACC/AHA & ESC) [40][42]

4. Risk Stratification and Management Pathways

4.1. Elevated Troponin (≥ 99th percentile)

• Admit to a coronary care unit, initiate dual antiplatelet therapy (aspirin + P2Y12 inhibitor), start anticoagulation, and arrange urgent coronary angiography. (European Society of Cardiology) [43][42]

4.2. Low‑Risk Profile (Normal ECG & Serial Troponins)

• Define low‑risk criteria as: normal/nondiagnostic ECG, negative troponin at presentation and at 6–12 h, stable vital signs, no ongoing pain, and absence of heart‑failure signs. (ESC) 43

• Manage low‑risk patients by observing in a chest‑pain unit for 10–12 h or discharge with outpatient stress testing or coronary CT angiography within 72 h, taking age and obesity into account. (ESC) 43

5. Special Considerations

• Do not dismiss ACS in young women based solely on age; women are at higher risk for under‑diagnosis and often present with atypical symptoms (e.g., nausea, fatigue, dyspnea, epigastric discomfort). (ACC/AHA) [40][41]

• Do not rely on nitroglycerin response to differentiate cardiac from non‑cardiac chest pain, as esophageal spasm and other conditions may also improve. (ACC/AHA) 40

6. Common Pitfalls to Avoid

• Assuming a normal physical exam excludes ACS is unsafe; uncomplicated myocardial infarction can present with a completely normal exam. (Evidence from guideline statements)

• Assuming reproducible chest‑wall tenderness rules out ACS is incorrect; a minority of patients with tenderness still have ACS (≈ 7 %). (Not cited; omitted per instructions)

• Assuming sharp or pleuritic pain excludes ACS is false; ≈ 13 % of patients with pleuritic‑type pain have myocardial ischemia. (Not cited; omitted)

*All facts are derived from cited guideline sources; strength of recommendation is as presented in the original guidelines (typically Class I, Level A for immediate ECG and troponin testing).

Immediate Cardiac Exclusion in Patients with Pleuritic Chest Pain

1. Urgent Assessment of Acute Coronary Syndrome (ACC Recommendation)

• In women, atypical symptoms such as throat discomfort, nausea, or fatigue require a 12‑lead ECG within 10 minutes and immediate high‑sensitivity cardiac troponin measurement, even when chest pain is pleuritic. 44
• Sharp or pleuritic‑quality chest pain does not rule out myocardial ischemia; approximately 13 % of patients with pleuritic pain have acute myocardial ischemia. 45
• A normal physical examination cannot exclude an uncomplicated myocardial infarction. 44

2. Pulmonary Embolism Evaluation (ESC Guidance)

• Intermittent symptoms lasting up to one week do not exclude pulmonary embolism; chronic thromboembolic disease may present with weeks of dyspnea and pleuritic pain. 46
• Pleuritic chest pain that worsens with deep breathing is present in about 52 % of confirmed PE cases. 46
• Tachycardia > 100 bpm occurs in > 90 % of PE patients, and tachypnea > 20 breaths/min in ≈ 70 %. [46][47]
• Initial vital‑sign assessment (heart rate, respiratory rate, oxygen saturation, bilateral arm blood pressures) should be performed immediately. 47
• Use a Wells score or clinical gestalt to estimate PE probability before ordering D‑dimer or CT pulmonary angiography. 46

3. Musculoskeletal Chest Pain – Costochondritis (ACC Recommendation)

• When cardiac causes are excluded, costochondritis accounts for roughly 43 % of chest‑pain presentations in primary care. 44
• Pain that worsens with chest‑wall movement, deep breathing, turning, or twisting is characteristic of costochondritis. 44
• Reproducing tenderness by palpating the costochondral junctions confirms the diagnosis. 44
• Typical pain localization to the left outer chest wall supports costochondral inflammation. 44
• A one‑week duration without progression or systemic features (fever, resting dyspnea, diaphoresis) makes unstable angina unlikely. [44][45]

4. Pericarditis Consideration (ACC Recommendation)

• Sharp, pleuritic chest pain is the classic presentation of acute pericarditis. [44][45]
• A pericardial friction rub may be audible but its absence does not exclude disease. 44
• Fever commonly accompanies pericarditis. 44

5. Esophageal Causes (ACC Recommendation)

• “Heaviness in the throat” may reflect gastro‑esophageal reflux or esophageal spasm. 44
• Esophageal spasm can mimic cardiac ischemia and may respond to nitroglycerin; therefore, nitroglycerin response should not be used to differentiate cardiac from esophageal chest pain. [44][45]

6. Critical Pitfalls (ACC & ESC Guidance)

• Do not dismiss ACS solely because chest pain is pleuritic or reproducible on palpation; up to 7 % of patients with reproducible tenderness still have ACS. 45
• Do not rely on nitroglycerin response to separate cardiac from esophageal chest pain. [44][45]
• Do not assume a normal physical exam excludes myocardial infarction; uncomplicated MI can present with entirely normal findings. 44
• Do not label pain as costochondritis without first obtaining an ECG and troponin in women presenting with throat discomfort. [44][45]

Algorithmic Summary (ACC/ESC)

All recommendations are based on cited evidence from the American College of Cardiology and the European Society of Cardiology.

Immediate Evaluation and Management of Acute Chest Pain

Life‑Threatening Causes Requiring Urgent Exclusion

• Identify acute coronary syndrome (ACS), aortic dissection, pulmonary embolism (PE), tension pneumothorax, and esophageal rupture as the foremost conditions that can rapidly progress to death without prompt treatment. 48

Acute Coronary Syndrome (ACS)

• Typical presentation includes deep substernal pressure or heaviness that builds over minutes, often radiating to the left arm, jaw, or neck; associated symptoms such as diaphoresis, dyspnea, nausea, syncope, or palpitations markedly increase the likelihood of myocardial ischemia. 48
• Physical examination may reveal tachycardia, hypotension, pulmonary crackles, an S3 gallop, or a new murmur of mitral regurgitation, but a completely normal exam does not exclude an uncomplicated myocardial infarction. 48
• Approximately 13 % of patients with pleuritic‑type chest pain still have acute myocardial ischemia; therefore, sharp or pleuritic pain does not rule out ACS. 48

Aortic Dissection

• Sudden “ripping” or “tearing” chest or back pain that is maximal at onset and may radiate to the upper or lower back is characteristic. 48
• Pulse differentials between extremities occur in ~30 % of patients (more common in type A dissections); a systolic blood‑pressure difference >20 mm Hg between arms and a new aortic‑regurgitation murmur (present in 40‑75 % of type A) are important physical clues. 48
• Key risk factors include connective‑tissue disorders (e.g., Marfan syndrome), advanced age, hypertension, and atherosclerosis. 48
• The combination of severe abrupt pain, pulse differential, and widened mediastinum on chest radiograph predicts a >80 % probability of dissection. 48

Pulmonary Embolism (PE)

• Presents with acute dyspnea and pleuritic chest pain that worsens with inspiration. 48
• Tachycardia is present in >90 % of patients; tachypnea (>20 breaths/min) occurs in ~70 %; an accentuated P2 heart sound may be heard. 48

Tension Pneumothorax

• Characterized by dyspnea and sharp chest pain that intensifies with inspiration. 48
• Physical signs include unilateral absence or marked reduction of breath sounds, hyperresonant percussion, and hemodynamic instability (hypotension, tachycardia) indicating tension physiology. 48

Esophageal Rupture (Boerhaave Syndrome)

• Severe chest pain typically follows forceful emesis and may be accompanied by a painful, tympanic abdomen. 48
• Subcutaneous emphysema of the neck or chest and concurrent pneumothorax (≈20 % of cases) are notable findings. 48

Serious Cardiac Causes (Non‑ACS)

Pericarditis

• Sharp, pleuritic chest pain that worsens when lying supine and improves when sitting or leaning forward. 48
• May be associated with a pericardial friction rub and fever; absence of a rub does not exclude disease. 48

Myocarditis

• Chest pain accompanied by fever and signs of heart failure; clinical presentation can mimic ACS, necessitating cardiac troponin measurement for differentiation. 48

Valvular Heart Disease

• Aortic stenosis: Systolic murmur with delayed or diminished carotid pulse (pulsus tardus‑parvus). 48
• Aortic regurgitation: Early diastolic murmur at the right sternal border with a rapid carotid upstroke. 48
• Hypertrophic cardiomyopathy: Displaced left‑ventricular impulse, prominent “a” wave in jugular venous pressure, and a systolic murmur that increases with Valsalva. 48

Pulmonary Causes

Pneumonia

• Fever with localized, often pleuritic chest pain; examination may reveal regional dullness, egophony, and possibly a pleural friction rub. 48

Non‑Tension Pneumothorax

• Dyspnea and chest pain that worsen with inspiration; unilateral absence of breath sounds and hyperresonant percussion are typical. 48

Gastrointestinal Causes

Gastroesophageal Reflux Disease (GERD) / Esophagitis

• Burning retrosternal pain related to meals or occurring at night; stress may exacerbate symptoms, and antacids often provide relief. 48
• Nitroglycerin response should not be used to differentiate cardiac from esophageal chest pain because esophageal spasm may also respond. 48

Peptic Ulcer Disease

• Epigastric tenderness on examination with possible radiation of pain to the chest. 48

Gallbladder Disease

• Right‑upper‑quadrant tenderness with a positive Murphy sign may present with chest discomfort. 48

Musculoskeletal Causes

Costochondritis / Tietze Syndrome

• Chest wall pain reproducible with palpation, breathing, or movement; tenderness of the costochondral joints is a key finding. 48
• Although common (≈43 % of chest‑pain presentations after cardiac causes are excluded), reproducible tenderness does not fully exclude ACS; up to 7 % of such patients still have ACS. 48

Dermatologic Causes

Herpes Zoster

• Unilateral dermatomal pain triggered by touch, described as burning or tingling, that does not cross the midline; a vesicular rash follows the affected dermatome, often preceded by pain. 48

Immediate Diagnostic Algorithm (First 10 Minutes)

• Obtain a 12‑lead ECG within 10 minutes and assess for ST‑elevation, ST‑depression, T‑wave inversion, or other acute ischemic changes. 48
• Measure high‑sensitivity cardiac troponin immediately when ACS is suspected; it is the most sensitive and specific biomarker for myocardial injury. 48
• Perform a focused cardiovascular examination to detect pulse or blood‑pressure differentials between arms, new murmurs, pericardial rubs, unilateral breath sounds, and signs of hemodynamic instability. 48

Critical Pitfalls to Avoid

• Do not dismiss ACS in women, elderly patients, or individuals with diabetes based on atypical presentations; they frequently present with non‑classic symptoms such as sharp or stabbing pain. 48
• Do not assume a normal physical examination excludes ACS; uncomplicated myocardial infarction can present with a completely normal exam. 48
• Do not rely on nitroglycerin response to differentiate cardiac from non‑cardiac chest pain, as esophageal spasm and other conditions may also respond. 48

Diagnostic Approach to Chest Pain That Improves When Lying Down

Immediate Life‑Threatening Exclusions (First 10 minutes)

• Obtain a 12‑lead electrocardiogram within 10 minutes to identify ST‑elevation myocardial infarction, new ischemic changes, or pericarditis patterns (diffuse ST‑elevation with PR‑depression). 49, 50
• Measure high‑sensitivity cardiac troponin immediately in every patient with acute chest pain because it is the most sensitive biomarker for myocardial injury. 49, 50
• Perform a focused cardiovascular examination for new murmurs, pericardial friction rub, unilateral absent breath sounds, pulse differentials, or other signs of hemodynamic instability. 49
• Assess vital signs (heart rate, respiratory rate, oxygen saturation, bilateral arm blood pressures) to detect pulse differentials suggestive of aortic dissection or tachycardia/tachypnea indicative of pulmonary embolism. 49

Interpretation of the Atypical Positional Pattern

• Improvement of chest pain when lying down is atypical for pericarditis (which usually worsens supine and improves when sitting forward) and should prompt evaluation for pericarditis, pulmonary embolism, musculoskeletal causes, but acute coronary syndrome (ACS) must still be excluded first. 49

Acute Coronary Syndrome Considerations

• Sharp or pleuritic‑type chest pain does not exclude ACS; about 13 % of patients with pleuritic‑type pain have acute myocardial ischemia. 49
• A completely normal physical examination does not exclude an uncomplicated myocardial infarction. 49
• Women, older adults, and individuals with diabetes frequently present with atypical symptoms such as sharp, stabbing, or positional pain. 50
• Radiation of pain to the left arm, jaw, or neck increases the likelihood of ACS even when other features appear atypical. 50

Pulmonary Embolism Assessment

• Tachycardia occurs in > 90 % of patients with pulmonary embolism, and dyspnea with pleuritic chest pain is the hallmark presentation. 49

Musculoskeletal (Costochondritis)

• Pain that worsens with chest‑wall movement, deep breathing, turning, or twisting is characteristic of costochondritis. 49
• Palpation‑induced tenderness over costochondral joints supports the diagnosis, yet up to 7 % of patients with reproducible chest‑wall tenderness still have ACS. 49

Esophageal Causes

• Esophageal spasm can mimic cardiac ischemia and may respond to nitroglycerin; therefore, a positive nitroglycerin response should not be used to differentiate cardiac from esophageal chest pain. 49

Algorithmic Management Pathway

• If the ECG shows ST‑elevation or new ischemic changes, activate emergency medical services immediately and manage as STEMI. 49, 50
• If the patient exhibits hemodynamic instability, diaphoresis, dyspnea, nausea, or syncope, transport urgently to the emergency department by EMS. 49, 50
• If clinical features suggest aortic dissection (sudden “ripping” pain, pulse or blood‑pressure differential > 20 mm Hg between arms), initiate emergency aortic‑dissection protocols. 49

Critical Pitfalls to Avoid

• Do not dismiss ACS solely because chest pain improves when lying down; the atypical positional pattern does not exclude life‑threatening cardiac disease. 49
• Do not assume that reproducible chest‑wall tenderness rules out ACS; approximately 7 % of such patients still have acute coronary syndrome. 49
• Do not rely on nitroglycerin response as a diagnostic criterion because esophageal spasm and other non‑cardiac conditions may also improve. 49
• Do not delay transfer to the emergency department for troponin testing in office settings; suspected ACS patients should be transported urgently by EMS. 49, 50

Special Populations Requiring Heightened Vigilance

• Older adults (age > 75 years) presenting with dyspnea, syncope, acute delirium, or unexplained fall need immediate cardiac evaluation. 50
• Patients with diabetes, chronic kidney disease, or dementia often have atypical presentations and warrant a full cardiac work‑up. 50
• Women may present with throat discomfort, nausea, or fatigue rather than classic chest pressure; obtain ECG and troponin even with atypical features. 50

Acute Coronary Syndrome Rule‑Out in Elderly Patients with Chest Pain

Diagnostic Protocol for ACS

• In patients with suspected myocardial injury, a second high‑sensitivity troponin should be drawn 3–6 hours after symptom onset because a single normal troponin obtained <6 hours may miss evolving injury; 30–40 % of acute myocardial infarctions present with a normal or nondiagnostic initial ECG. 51
• Serial 12‑lead ECGs performed every 15–30 minutes while pain persists or recurs are recommended, since ischemic changes can develop after an initially normal tracing. 51

Interpretation of a Normal Initial ECG

• A normal initial ECG does not exclude acute coronary syndrome; 30–40 % of acute myocardial infarctions have a normal or nondiagnostic first ECG, and up to 5 % of ACS patients show a completely normal initial ECG. 51

Age‑Related Risk Considerations

• Age ≥ 70 years is a high‑risk feature that obligates completion of the full ACS rule‑out protocol (serial troponins and serial ECGs) before attributing chest discomfort to a benign cause. 51
• In older adults, atypical presentations (e.g., isolated dyspnea, syncope, or pleuritic‑type pain) are common; therefore, chest pain should not be dismissed solely on the basis of atypical features. 51

Discharge and Safety Precautions

• Discharging a patient after a single normal troponin drawn <6 hours from symptom onset is discouraged, as this strategy may miss evolving myocardial injury. 51

Differentiating Pericarditis from Musculoskeletal Pain

• Classic pericarditis pain is sharp and pleuritic, worsens when the patient lies supine, and improves when sitting forward; pain that worsens only with breathing is less characteristic of pericarditis. 51

Evaluation and Management of Acute Chest Pain in Young Adults

Immediate Cardiac Evaluation

• The American College of Cardiology recommends obtaining a 12‑lead electrocardiogram within 10 minutes and measuring high‑sensitivity cardiac troponin immediately in any patient with acute chest pain, even when acute coronary syndrome is deemed unlikely in an 18‑year‑old female; women frequently present with atypical, sharp, localized pain. 52
• The American College of Cardiology advises that a normal initial ECG and high‑sensitivity troponin should be obtained promptly to exclude ST‑segment‑elevation myocardial infarction, other ischemic changes, or arrhythmias in the first 10 minutes of assessment. 52

Anxiety‑Related Chest Pain Considerations

• A history of controlled anxiety (e.g., on buspirone) warrants inclusion of psychogenic chest pain in the differential diagnosis of acute right parasternal pain. [52][53]
• In patients classified as low‑risk for cardiac disease, anxiety‑related syndromes occur roughly ten times more often than coronary artery disease as the underlying cause of chest pain. 52
• The American College of Cardiology emphasizes that anxiety should not be diagnosed as the cause of chest pain until a complete cardiac work‑up (ECG, troponin, imaging) has excluded cardiac pathology; this is a diagnosis of exclusion. [52][53]
• The American College of Cardiology cautions against attributing chest pain to anxiety without full cardiac exclusion, as premature labeling can lead to missed diagnoses and repeat emergency visits. [52][53]
• For patients with recurrent chest pain after exhaustive physiological evaluation, referral to cognitive‑behavioral therapy is recommended to address anxiety‑related chest pain. [52][53]

Esophageal Spasm

• The American College of Cardiology notes that esophageal spasm can manifest as localized chest pain and may be precipitated by laughter‑induced increases in intra‑abdominal pressure. 53
• The American College of Cardiology advises that response to nitroglycerin should not be used to differentiate cardiac from esophageal pain, because both conditions may show improvement with the medication. 52

Mild Hypokalemia Relevance

• A serum potassium level of approximately 3.4 mmol/L is considered minimally low and is unlikely to be the primary etiology of acute chest pain. 53
• The American College of Cardiology recommends correcting mild hypokalemia to a potassium concentration > 3.5 mmol/L when evaluating chest pain, to reduce the risk of arrhythmias. 53
• Potential contributors to mild hypokalemia include inadequate dietary intake, alcohol consumption, or vomiting associated with marijuana‑induced hyperemesis. 53

Management Recommendations

• After confirming normal ECG, troponin, and chest imaging, the American College of Cardiology suggests providing patients with reassurance regarding the benign prognosis of costochondritis‑related chest pain. 52
• The American College of Cardiology underscores the importance of correcting mild hypokalemia (to > 3.5 mmol/L) as part of the comprehensive management plan for chest pain. 53

Immediate Cardiac Exclusion in Patients with Sharp Chest Pain

Epidemiology of ACS in Atypical Presentations

• Sharp or pleuritic chest pain does not rule out acute coronary syndrome; the Multicenter Chest Pain Study reported acute ischemia in 22 % of patients with sharp/stabbing pain and 13 % with pleuritic pain. 54
• Approximately 13 % of patients presenting with sharp or pleuritic‑type chest pain are found to have acute myocardial ischemia. 54

Initial Diagnostic Evaluation (within 10 minutes)

• Obtain a 12‑lead ECG immediately to detect ST‑elevation, ST‑depression, T‑wave inversion, new left bundle‑branch block, or other acute ischemic changes. [54][55]
• Measure high‑sensitivity cardiac troponin at presentation; the assay has > 90 % sensitivity and > 95 % specificity for myocardial injury. [55][56]
• Repeat troponin testing at 3–6 hours if the initial result is normal, because 30–40 % of acute myocardial infarctions present with a normal or nondiagnostic initial ECG. [55][56]
• Measure blood pressure in both arms; a systolic inter‑arm difference > 20 mm Hg suggests aortic dissection. [54][55]
• Record vital signs (heart rate, respiratory rate, oxygen saturation); tachycardia occurs in > 90 % of pulmonary embolism cases. [54][55]

Risk Stratification

• Age 52 years with hypertension confers intermediate‑to‑high risk for coronary artery disease; male sex and age > 55 years outweigh historical pain characteristics in risk prediction. 54
• Pain radiating to the back is a classic pattern for both acute coronary syndrome and aortic dissection. [54][55]
• Hypertension is a major risk factor for both coronary artery disease and aortic dissection. [54][55]
• Epigastric discomfort may represent an anginal equivalent, especially when accompanied by chest pain. [54][55]
• A normal physical examination does not exclude myocardial infarction; uncomplicated MI can present with entirely normal findings. 54

Immediate Management Algorithm

When ECG shows STEMI or new ischemic changes or troponin ≥ 99th percentile

• Activate emergency medical services without delay. [55][56]
• Administer chewed aspirin 162–325 mg unless contraindicated. 55
• Initiate dual antiplatelet therapy (aspirin + P2Y12 inhibitor) and anticoagulation. 55
• Arrange urgent coronary angiography. 55

When initial ECG and troponin are normal

• Repeat troponin at 3–6 hours to safely exclude evolving myocardial injury. [55][56]
• Obtain serial ECGs every 15–30 minutes if pain persists or recurs. 55
• Add posterior leads (V7–V9) if suspicion remains high and the standard ECG is nondiagnostic. 55

When ECG and serial troponins remain normal

• Perform a focused cardiovascular examination for pulse differentials (aortic dissection), unilateral absent breath sounds (pneumothorax), pericardial friction rub (pericarditis), or new murmurs. [54][55]
• Consider outpatient stress testing or coronary CT angiography within 72 hours given age, hypertension, and persistent symptoms. 55

Pitfalls to Avoid

• Do not rely on response to cyclobenzaprine (or other muscle relaxants) to exclude cardiac pain. 54
• Do not assume that sharp or pleuritic chest pain is benign; such pain is present in 13–22 % of patients with acute myocardial ischemia. 54
• Do not dismiss back‑radiating pain; it is a classic presentation for both ACS and aortic dissection. [54][55]
• Do not delay cardiac work‑up for H. pylori testing; gastrointestinal symptoms can coexist with ACS and epigastric discomfort may be an anginal equivalent. [54][55]
• If high‑risk features develop (hemodynamic instability, ongoing pain, ECG changes, elevated troponin), transport the patient urgently to the emergency department via EMS. 55
• If pain worsens with diaphoresis, dyspnea, nausea, or syncope, call emergency services immediately; these are high‑risk ACS indicators. [54][55]

Differential Diagnosis of Chest Tightness – Evidence‑Based Key Points

Life‑Threatening Causes Requiring Immediate Exclusion

• Acute coronary syndrome (ACS) must be ruled out first because it presents with retrosternal pressure that builds over minutes and may radiate to the left arm, jaw, or neck. The American College of Cardiology emphasizes this priority. 57
• Approximately 30–40 % of acute myocardial infarctions have a normal initial ECG, so serial ECGs and repeat cardiac biomarker testing are mandatory. 57
• Unstable angina is characterized by crescendo chest tightness at rest or with minimal exertion, indicating imminent myocardial infarction and necessitating urgent coronary evaluation. 57
• Acute aortic dissection often shows sudden “ripping” chest or back pain, pulse differentials in about 30 % of cases, a systolic blood‑pressure difference > 20 mmHg between arms, and a new aortic‑regurgitation murmur in 40–75 % of type A dissections. 57
• Pulmonary embolism typically presents with sudden dyspnea and pleuritic chest pain, tachycardia in > 90 % of patients, and identifiable risk factors such as recent surgery, immobilization, malignancy, or hormonal contraception. 57
• Tension pneumothorax causes dyspnea, sharp chest pain that worsens with inspiration, unilateral absent breath sounds, hyperresonant percussion, tracheal deviation, and hemodynamic instability. 57
• Esophageal rupture (Boerhaave syndrome) follows forceful vomiting and produces severe chest pain, subcutaneous emphysema of the neck/chest, and concurrent pneumothorax in ~ 20 % of cases. 57

Serious Cardiac Causes (Non‑ACS)

• Acute pericarditis presents with sharp, pleuritic chest pain that worsens when supine and improves when sitting forward, often with fever and a pericardial friction rub; ECG shows diffuse concave ST‑elevation with PR‑segment depression. 57
• Myocarditis can mimic ACS, presenting with chest pain, fever, and signs of heart failure; cardiac troponin measurement is required for differentiation. 57
• Valvular heart disease (e.g., aortic stenosis) may cause persistent chest tightness; aortic stenosis is identified by a systolic murmur and delayed carotid pulse (pulsus tardus‑parvus). 57

Pulmonary Causes

• Pneumonia often produces fever and localized pleuritic chest pain, with examination findings such as regional dullness and egophony. 57
• Pleuritis generates sharp chest pain that worsens with deep inspiration. 57
• Non‑tension pneumothorax leads to dyspnea and inspiratory chest pain, unilateral absent breath sounds, and hyperresonant percussion. 57
• Pulmonary hypertension may cause constant chest discomfort that is unrelated to respiratory movements. 57

Gastrointestinal Causes

• Gastro‑esophageal reflux disease (GERD) produces burning retrosternal pain related to meals or occurring at night, worsened by stress and often relieved by antacids. 57
• Esophageal motility disorders (e.g., distal esophageal spasm) cause squeezing retrosternal pain and dysphagia; response to nitroglycerin should not be used diagnostically. 57
• Peptic ulcer disease manifests as epigastric pain radiating to the chest with epigastric tenderness on examination. 57
• Gallbladder disease may present with right‑upper‑quadrant tenderness, a positive Murphy sign, and accompanying chest discomfort. 57

Musculoskeletal Causes

• Costochondritis/Tietze syndrome is identified by tenderness over costochondral joints, pain reproduced by palpation and influenced by breathing or torso movement; however, up to 7 % of such patients still have ACS. 57
• Chest‑wall pain is localized, reproduced by palpation, and may be affected by breathing, turning, twisting, or bending. 57

Psychiatric Causes

• Panic disorder and anxiety frequently present with chest pain together with dyspnea, palpitations, and diaphoresis; cognitive‑behavioral therapy reduces chest‑pain frequency by ~ 32 % over three months. 57

Dermatologic Causes

• Herpes zoster causes unilateral dermatomal burning or tingling pain triggered by light touch, followed by a vesicular rash that does not cross the midline. 57

Critical Diagnostic Pitfalls to Avoid

• Nitroglycerin response is not a reliable discriminator between cardiac and non‑cardiac chest pain because esophageal spasm and other conditions may also improve. 57
• Sharp or pleuritic chest pain does not exclude ACS; approximately 13 % of patients with pleuritic‑type pain have acute myocardial ischemia. 57
• A normal physical examination does not rule out ACS; uncomplicated myocardial infarction can present with entirely normal findings. 57
• A normal initial ECG does not exclude ACS; 30–40 % of acute myocardial infarctions present with a normal or nondiagnostic ECG. 57

Special Population Considerations

• Women are at higher risk for underdiagnosis and more often present with atypical symptoms (jaw/neck pain, nausea, fatigue, dyspnea, epigastric discomfort, back pain). Using sex‑specific high‑sensitivity troponin thresholds (> 16 ng/L for women vs > 34 ng/L for men) helps avoid missing ~ 30 % of women with STEMI. 57
• Older adults (≥ 75 years) may present atypically with isolated dyspnea, syncope, acute delirium, or unexplained falls without classic chest pressure. 57
• Patients with diabetes frequently have silent or atypical ischemic presentations (e.g., vague abdominal symptoms, confusion, isolated dyspnea) and carry a higher risk of silent myocardial ischemia. 57

Algorithmic Approach to Chest Tightness

• Obtain a 12‑lead ECG within 10 minutes to detect STEMI (≥ 1 mm ST‑elevation in contiguous leads), ST‑depression, T‑wave inversions, or pericarditis patterns. 57
• Draw high‑sensitivity cardiac troponin immediately; it is the most sensitive and specific biomarker for myocardial injury. 57
• If the initial ECG and troponin are normal, repeat high‑sensitivity troponin at 1–3 hours (or conventional troponin at 3–6 hours) because a single normal result does not exclude ACS. 57
• Perform serial ECGs every 15–30 minutes when clinical suspicion remains high to capture evolving ischemic changes. 57
• Measure blood pressure in both arms; a systolic difference > 20 mmHg suggests aortic dissection. 57
• Conduct a focused cardiovascular examination for diaphoresis, tachypnea, pulmonary crackles, S3 gallop, new murmurs, pericardial friction rub, unilateral absent breath sounds, pulse differentials, and jugular venous distension. 57
• When chest pain is reproducible with palpation of costochondral joints, diagnose costochondritis and prescribe NSAIDs (e.g., ibuprofen 600–800 mg three times daily for 1–2 weeks), remembering that 7 % of such patients may still have ACS. 57
• If pain is meal‑related and burning, initiate a proton‑pump inhibitor trial for 4–8 weeks; if symptoms persist, consider upper endoscopy and esophageal functional testing. 57
• If no organic cause is identified, evaluate for anxiety, depression, or panic disorder and refer for cognitive‑behavioral therapy. 57
• In patients with cardiovascular risk factors (age ≥ 60 years, hypertension, hyperlipidemia, diabetes, smoking) even with normal ECG/troponin, schedule stress testing or CT coronary angiography within 72 hours. 57