What are the typical symptoms of abdominal, thoracic, cerebral, and peripheral arterial aneurysms, and how do they present when ruptured?

Aneurysm Symptoms: Clinical Presentation by Location

Most aneurysms are asymptomatic until complications occur, but when symptomatic, presentation varies dramatically by anatomical location—cerebral aneurysms present with headache and cranial nerve deficits, thoracic aneurysms with chest/back pain, abdominal aneurysms with pulsatile mass or pain, and peripheral aneurysms with thromboembolism rather than rupture.

Cerebral Aneurysms

Unruptured Presentation

• 51% are completely asymptomatic and discovered incidentally on imaging obtained for unrelated causes 1
• 17% present acutely with ischemia (37%), headache (37%), seizures (18%), or cranial neuropathies (12%) 1
• 32% present with chronic symptoms including persistent headache (51%), visual deficits (29%), weakness (11%), and facial pain (9%) 1
• Larger aneurysms (average 2.1-2.2 cm) are more likely to be symptomatic, while asymptomatic ones average 1.1 cm 1
• Symptomatic aneurysms tend to locate along the proximal internal carotid artery with diameters never smaller than 3 mm 1
• Isolated oculomotor nerve palsy typically indicates posterior circulation aneurysm 2

Ruptured Presentation (Subarachnoid Hemorrhage)

• Sudden, severe "thunderclap" headache is the hallmark symptom 2
• Nausea, vomiting, photophobia, and nuchal rigidity are typical 1
• Altered level of consciousness, focal weakness, and cranial nerve deficits commonly occur 1
• Critical pitfall: Milder presentations with vague headache may result in delayed or missed diagnosis 2

Thoracic Aortic Aneurysms

Unruptured Presentation

• Most are clinically silent and discovered incidentally on imaging for other causes 1
• When symptomatic, patients describe chest or back pain 1
• Uncommon mass effect symptoms from large aneurysms include dysphagia (esophageal compression), hoarseness (recurrent laryngeal nerve compression), or vascular compression 1
• Intrathoracic mycotic aneurysms present with fever, chest and interscapular pain, often with findings of infective endocarditis 1

Ruptured or Contained Rupture Presentation

• Acute onset of severe chest and/or back pain is the primary symptom 1
• Patients with contained rupture remain hemodynamically stable, unlike free rupture 1
• Rare but catastrophic presentations include hemoptysis from aortobronchial fistula or hematemesis from aortoesophageal fistula 1
• Acute respiratory failure may result from rupture into left hemithorax 1
• Mortality is extremely high: 54% at 6 hours and 76% at 24 hours after rupture 1

Abdominal Aortic Aneurysms

Unruptured Presentation

• Majority (approximately 70%) are asymptomatic and detected incidentally on imaging 3, 4
• 30% discovered as pulsatile abdominal mass on routine physical examination 4
• When symptomatic, present with abdominal pain or back pain 3, 4
• Classic triad of fever, pain, and pulsatile mass is actually uncommon and suggests mycotic aneurysm 1
• Mycotic aneurysms present with fever (>70% of cases) and back pain (65-90% of cases) 1

Ruptured Presentation

• Medical emergency with hypotension, shooting abdominal or back pain, and pulsatile abdominal mass 3
• Associated with high prehospitalization mortality 3
• Contained rupture: severe pain with hemodynamic stability, sealed by retroperitoneal structures 1
• Free rupture: massive hemorrhage leading rapidly to death 1

Peripheral Arterial Aneurysms

Popliteal Aneurysms

• Often asymptomatic until complications occur 5, 6
• Thromboembolism is the primary risk, not rupture—contributing greater morbidity than rupture 6
• May present with neurological symptoms from pressure on adjacent nerves 5
• Venous thrombosis can occur from compression 5
• Acute limb ischemia from thrombosis or embolization is the most common presentation 6
• Critical threshold: Aneurysms ≥2.0 cm require urgent surgical repair due to high thromboembolism risk 7

Femoral Aneurysms

• May present as pulsatile groin mass 7
• Physical examination alone misses >60% of cases—imaging is mandatory 8
• Symptomatic presentations include expanding or painful thigh mass, active bleeding, compressive symptoms, or unexplained anemia 8

Visceral Artery Aneurysms

• Superior mesenteric aneurysms: acute abdominal pain, fever, rarely palpable epigastric mass, catastrophic GI hemorrhage 1
• Hepatic artery aneurysms: fever, colicky upper abdominal pain, hemobilia, jaundice, GI hemorrhage 1
• Renal artery aneurysms: fever, hematuria, elevated blood pressure 1

Pseudoaneurysms (Femoral/Profunda Femoris)

• All symptomatic pseudoaneurysms require repair regardless of size 8
• Present with expanding or painful thigh mass, active bleeding, skin erosion, compressive symptoms, or unexplained anemia requiring transfusions 8
• Deep femoral artery pseudoaneurysms have 33% rupture rate—higher than other lower extremity locations 8
• Post-catheterization pseudoaneurysms <2.0 cm may be observed if asymptomatic 9

Key Clinical Pitfalls

• Never assume a pulsatile mass is benign without imaging confirmation—ultrasound with Doppler is mandatory first-line study 7
• Do not rely on physical examination alone for peripheral aneurysms—imaging sensitivity approaches 100% while exam misses >60% 8, 7
• Recognize that peripheral aneurysms often coexist with aortic and other peripheral aneurysms—screen comprehensively 6
• Mild headache presentations of ruptured cerebral aneurysms can be missed—maintain high suspicion 2
• Sudden onset pain in known aneurysm suggests dissection, hemorrhage, or impending rupture—requires emergent imaging 1