What is the differential diagnosis for sudden severe epigastric pain radiating to the back with a normal electrocardiogram?

Differential Diagnosis of Sudden Sharp Epigastric Pain Radiating to Back with Normal ECG

When sudden severe epigastric pain radiates to the back with a normal ECG, acute pancreatitis and acute aortic syndromes are the two most critical life-threatening diagnoses that must be excluded immediately, followed by consideration of peptic ulcer perforation, esophageal rupture, and other gastrointestinal emergencies. 1, 2

Immediate Life-Threatening Conditions (Rule Out First)

Acute Aortic Syndromes

• Aortic dissection presents with sudden "ripping" chest or back pain radiating to the back, though a pulse differential is present in only 30% of cases 1, 3
• The normal ECG does not exclude aortic dissection—this diagnosis requires immediate CT angiography or transesophageal echocardiography 1
• Mortality is extremely high if missed, making this the first diagnosis to exclude despite normal cardiac testing 1

Acute Pancreatitis

• Classic presentation is severe epigastric pain radiating to the back, often accompanied by nausea and vomiting 1, 2
• Pain radiating to the back is a key distinguishing feature that raises suspicion for pancreatitis over other gastrointestinal causes 1
• Serum lipase and amylase should be measured immediately; lipase is more specific 4, 5
• Abdominal ultrasound or CT can confirm the diagnosis and assess for complications 5, 6
• Critical pitfall: Acute pancreatitis can cause ECG changes mimicking myocardial infarction, but troponin remains negative 5, 6

Peptic Ulcer Perforation

• Sudden severe epigastric pain with fever and abdominal rigidity suggests perforation, which carries mortality rates up to 30% if treatment is delayed 1, 2
• Perforation is a surgical emergency requiring immediate surgical consultation 2
• Upright chest X-ray or CT abdomen may show free air under the diaphragm 1

Esophageal Rupture (Boerhaave Syndrome)

• Presents with sudden severe chest or epigastric pain, often after forceful vomiting 1
• Chest pain accompanied by a painful, tympanic abdomen may indicate this life-threatening gastrointestinal emergency 1
• Requires immediate CT imaging with oral contrast and emergent surgical consultation 1

Secondary Gastrointestinal Causes

Peptic Ulcer Disease (Without Perforation)

• Epigastric pain may radiate to the back but is typically less acute in onset than perforation 1, 2
• PUD has an incidence of 0.1-0.3%, with complications occurring in 2-10% of cases 1
• Upper endoscopy is the diagnostic test of choice when PUD is suspected 2

Gastroesophageal Reflux Disease (GERD) / Esophagitis

• GERD affects approximately 42% of Americans monthly, though daily symptoms occur in only 7% 1
• Retrosternal pain can occur with gastritis and esophagitis, which frequently coexist with PUD 2
• Distal esophageal wall thickening ≥5 mm on CT has moderate association with reflux esophagitis (sensitivity 56%, specificity 88%) 1, 2

Gastritis / Duodenal Ulcer

• Symptoms overlap extensively with GERD, esophagitis, and PUD, requiring careful history and often endoscopic evaluation 1, 2
• Both peptic ulcer disease and gastritis are commonly caused by Helicobacter pylori infection (42% of cases) and NSAID use (36% of cases) 2

Cardiac Considerations (Despite Normal ECG)

Myocardial Infarction

• Critical pitfall: Myocardial infarction can present atypically with epigastric pain, particularly in women, diabetics, and elderly patients 4
• A single normal ECG does not exclude MI—serial troponins at 0 and 6 hours are mandatory 4
• Approximately 13% of patients with pleuritic-type chest pain have acute myocardial ischemia 3
• The normal ECG in this case makes acute MI less likely but does not completely exclude it without serial troponin measurements 1, 4

Diagnostic Algorithm

First 10 Minutes

• Obtain vital signs immediately, looking for tachycardia, hypotension, or fever suggesting perforation or shock 1, 3
• Measure cardiac troponin at presentation (time 0) and repeat at 6 hours to definitively exclude myocardial infarction 1, 4
• Order serum lipase/amylase to evaluate for acute pancreatitis 4, 5
• Perform focused cardiovascular examination to assess for pulse differentials (aortic dissection), friction rub (pericarditis), or signs of heart failure 1
• Assess abdomen for peritoneal signs (rigidity, rebound tenderness) suggesting perforation 2

Immediate Imaging

• CT angiography of chest/abdomen is the single most useful test when pain radiates to the back, as it can identify aortic dissection, pancreatitis, and perforation in one study 1
• Upright chest X-ray may show free air under diaphragm if perforation is present 1
• Abdominal ultrasound can identify gallstones, pancreatic inflammation, or free fluid but is less sensitive than CT for acute emergencies 5, 7

Risk Stratification

• High-risk features requiring immediate CT imaging: sudden onset, severe intensity, radiation to back, hemodynamic instability, peritoneal signs 1, 2, 8
• Moderate-risk features allowing stepwise workup: gradual onset, stable vital signs, no peritoneal signs, relieved by antacids 1

Critical Pitfalls to Avoid

• Never dismiss aortic dissection based on normal ECG alone—pulse differential is present in only 30% of cases, and ECG is typically normal 1, 3
• Do not rely on single troponin measurement—serial measurements at 0 and 6 hours are mandatory to exclude MI 4
• Recognize that acute pancreatitis can cause ECG changes mimicking myocardial infarction, but troponin remains negative 5, 6
• Pain radiating to the back is a red flag that mandates consideration of pancreatitis and aortic syndromes before attributing symptoms to benign gastrointestinal causes 1, 2
• Sudden severe epigastric pain with fever and rigidity requires immediate surgical consultation for possible perforation, which has 30% mortality if delayed 2