What is the current management approach for a patient with aortic dissection, including recent studies and trials?

Current Management of Aortic Dissection

Immediate Management and Stabilization

All patients with suspected aortic dissection require immediate transfer to an intensive care unit with invasive arterial line monitoring and continuous ECG recording. 1, 2, 3

Hemodynamic Control (First Priority)

• Target systolic blood pressure 100-120 mmHg and heart rate ≤60 beats per minute to reduce aortic wall shear stress 1, 2, 3
• Administer intravenous beta-blockers as first-line therapy (labetalol preferred for combined alpha/beta blockade, or esmolol, propranolol, metoprolol) 2, 3
• Add sodium nitroprusside only after adequate beta-blockade if blood pressure remains elevated—never use vasodilators alone as reflex tachycardia increases aortic wall stress 2, 3
• If beta-blockers are contraindicated, use non-dihydropyridine calcium channel blockers for heart rate control 3
• Provide pain control with morphine sulfate to reduce sympathetic stimulation 2, 3

Diagnostic Imaging

• Perform urgent CT angiography, transesophageal echocardiography (TEE), or MRI with sensitivity and specificity >90% for all three modalities 2, 3, 4
• Select imaging based on institutional capabilities and patient stability—all three modalities are equally reliable 3, 4
• TEE sensitivity ranges 86-100% and allows rapid bedside assessment 5, 4
• Chest X-ray is abnormal in 60-90% of cases but should be omitted in unstable patients to avoid treatment delays 3

Type A Dissection (Ascending Aorta)

Emergency surgical intervention is mandatory for all Type A dissections to prevent aortic rupture, pericardial tamponade, and aortic regurgitation. 1, 2, 3

Surgical Approach

• Standard median sternotomy with extracorporeal circulation using moderate hypothermia 2
• Surgical options include supracommissural graft implantation, valve resuspension, composite graft with coronary reimplantation, or total arch replacement 2, 3
• Dissected layers are conjoined using Teflon felt strips or gelatin-resorcinol-formaldehyde glue 2
• Despite optimal management, mortality remains 26-58% for Type A dissections 4

Malperfusion Management

In Type A dissection with malperfusion (cerebral, mesenteric, renal, or limb), immediate aortic surgery is recommended (Class I, Level B). 1

• For cerebral malperfusion or non-hemorrhagic stroke, immediate surgery should be considered to improve neurological outcomes (Class IIa, Level B) 1
• For clinically significant mesenteric malperfusion, consider invasive angiographic diagnostics to evaluate percutaneous repair before or directly after aortic surgery in expert centers (Class IIa, Level C) 1

Type B Dissection (Descending Aorta)

Uncomplicated Type B Dissection

Uncomplicated Type B dissections are managed medically with aggressive blood pressure and heart rate control. 1

• Medical management reduces mortality to 25-27% compared to >50% without treatment 1
• Recent evidence from 2024 ESC guidelines indicates that pre-emptive TEVAR should be considered in stable Type B dissection with suitable anatomy and high-risk features to improve long-term outcomes and aortic remodeling 1
• High-risk features include: primary entry tear >10 mm at inner aortic curvature, initial aortic diameter >40 mm, false lumen diameter >20 mm, multiple fenestrations, or partial false lumen thrombosis 1
• The ongoing IMPROVE-AD trial is evaluating upfront TEVAR plus medical therapy versus medical therapy alone in subacute (48 hours to 6 weeks) uncomplicated Type B dissection 1

Complicated Type B Dissection

Endovascular therapy (TEVAR) is now first-line treatment for complicated acute Type B dissection with favorable anatomy, with open surgery reserved for unsuitable cases. 1, 6

Indications for intervention include:

• Persistent or recurrent pain despite medical therapy 1, 2
• Rapidly expanding aortic diameter 1, 2
• Malperfusion syndrome (mesenteric, renal, limb) 1, 6
• Rupture or signs of impending rupture (periaortic/mediastinal hematoma) 1, 3
• Dissection in previously aneurysmal aorta 3

TEVAR Technical Considerations

• TEVAR aims to cover the primary entry tear and redirect blood flow to the true lumen 2, 6
• Accurate endograft sizing is critical—use real-time imaging (especially IVUS) to account for aortic diameter fluctuations from hemorrhagic shock and resuscitation 1
• In selected cases, correct side branch compression before proximal sealing 1
• A 2022 meta-analysis demonstrated TEVAR superiority over medical therapy alone, with similar early outcomes but fewer long-term events and better aortic remodeling 1

Long-Term Management and Surveillance

Blood Pressure Control

• Transition to oral beta-blockers after 24 hours of hemodynamic stability 2, 3
• Target long-term blood pressure <135/80 mmHg (systolic <130 mmHg during exercise) 2, 7
• Most patients require combination antihypertensive therapy 7
• Lifelong beta-blocker therapy is mandatory for hereditary connective tissue disorders (Marfan syndrome, Loeys-Dietz syndrome, Ehlers-Danlos syndrome) 2, 3

Imaging Surveillance

• MRI is the preferred modality for serial follow-up as it avoids ionizing radiation and nephrotoxic contrast while providing excellent aortic visualization 7
• CT angiography is acceptable, particularly in patients >60 years where radiation exposure is less concerning 7
• For medically managed Type B dissection: obtain imaging at 1,3,6, and 12 months, then yearly if stable 7
• Monitor for false lumen expansion, aneurysm formation, or dissection progression 2, 7

Surgical Thresholds for Chronic Dissection

• Consider reoperation when dissected aorta reaches 5-6 cm diameter for Type A dissection 2, 7
• For Type B dissection, operate when descending thoracic aortic diameter reaches ≥60 mm in reasonable surgical risk patients 7
• TEVAR is preferred over open surgery when anatomy is suitable 7
• Rate of reoperation for Type A dissection is approximately 10% at 5 years and up to 40% at 10 years 2

Critical Pitfalls to Avoid

• Never use vasodilators without prior beta-blockade—reflex tachycardia increases aortic wall stress and worsens outcomes 2, 7
• Avoid dihydropyridine calcium channel blockers without beta-blockers for the same reason 2
• Do not delay imaging in unstable patients—proceed directly to operating room with intraoperative TEE if Type A dissection is highly suspected 8
• Mortality is 1-2% per hour in untreated patients, emphasizing the need for rapid diagnosis and treatment 3
• Patients must be followed by physicians with expertise in aortic dissection who can recognize subtle signs of disease progression 7

Recent Advances and Ongoing Research

The 2024 ESC guidelines represent the most current evidence, introducing the DISSECT classification system (Duration, Intimal tear location, Size, Segmental extent, Clinical complications, Thrombosis of false lumen) to guide therapeutic decisions 1. The shift toward pre-emptive TEVAR for uncomplicated Type B dissection with high-risk features represents an evolving paradigm, though the IMPROVE-AD trial results are pending to definitively establish this approach 1.