What is the management approach for aortic dissection?

Management of Aortic Dissection

Emergency surgical intervention is mandatory for Type A dissection, while Type B dissection is managed medically unless complications develop, with immediate blood pressure and heart rate control being critical for both. 1, 2

Immediate Stabilization (All Dissections)

Monitoring and Access

• Establish invasive arterial line monitoring and continuous three-lead ECG recording immediately upon suspicion 1, 2
• Transfer to intensive care unit for appropriate hemodynamic monitoring 2

Blood Pressure and Heart Rate Control

• Administer intravenous beta-blockers as first-line therapy targeting systolic blood pressure <120 mmHg (ideally 100-120 mmHg) and heart rate ≤60 beats per minute 1, 2
• Labetalol is preferred due to combined alpha- and beta-blocking properties 2
• Alternative beta-blockers include propranolol, esmolol, or metoprolol 2
• If beta-blockers are contraindicated, use intravenous non-dihydropyridine calcium channel blockers (verapamil or diltiazem) for heart rate control 1, 2
• Never use dihydropyridine calcium channel blockers without beta-blockers due to reflex tachycardia risk 3
• Add sodium nitroprusside only after adequate beta-blockade if severe hypertension persists 1, 2

Pain Management

• Provide morphine sulfate for pain relief, which also helps reduce sympathetic drive 2

Special Consideration for Malperfusion

• In cases of organ malperfusion, tolerate higher blood pressure to optimize perfusion to the threatened region 1, 2

Type A Dissection Management

Surgical Intervention

• Emergency surgical repair is mandatory to prevent aortic rupture, pericardial tamponade, and death 1, 2, 3
• Obtain urgent surgical consultation immediately upon diagnosis 2
• Never delay surgery for extensive imaging in hemodynamically unstable patients; transesophageal echocardiography can be performed as the sole diagnostic procedure in the operating room 3

Surgical Techniques

• Implant composite graft in the ascending aorta with or without coronary artery reimplantation 1, 2
• Use supracommisural graft implantation when the aortic root is normal and valve is intact 1
• Valve resuspension is adequate in approximately 50% of chronic Type A cases when commissures are detached 1
• When the aortic arch is involved, perform subtotal or total arch replacement with reconnection of supraaortic vessels during hypothermic circulatory arrest 1, 3
• Fortify dissected layers using gelatin resorcinol formaldehyde glue or teflon felt strips 3

Critical Pitfall

• Avoid pericardiocentesis before surgery in tamponade cases, as reducing intrapericardial pressure causes recurrent bleeding 3

Type B Dissection Management

Uncomplicated Type B

• Manage medically with aggressive blood pressure control and close surveillance 2, 4, 5
• Continue intravenous beta-blockers until hemodynamically stable for 24 hours 1, 2
• Switch to oral beta-blockers after 24 hours if gastrointestinal transit is preserved 1, 2, 3

Complicated Type B (Requires Emergency Intervention)

• Emergency intervention with thoracic endovascular aortic repair (TEVAR) is recommended for: 2, 4, 5
  • Malperfusion syndrome
  • Intractable pain despite medical therapy
  • Rapidly expanding aortic diameter
  • Periaortic or mediastinal hematoma
  • Dissection occurring in a previously aneurysmatic aorta
  • Inability to control blood pressure or symptoms
• TEVAR has contributed to a fourfold increase in early survival in complicated Type B dissection compared to open surgical repair 4

Visceral Ischemia Consideration

• Patients with visceral ischemia have poor prognosis even with TEVAR; early diagnosis and intervention are crucial 5

Long-Term Management and Follow-Up

Blood Pressure Control

• Target long-term blood pressure <135/80 mmHg 3
• Lifelong beta-adrenergic blockade is mandatory for patients with hereditary connective tissue disorders (Marfan syndrome, Ehlers-Danlos syndrome) 1, 2

Imaging Surveillance

• Perform CT and transthoracic echocardiography within 6 months, then at 12 months, and yearly if stable 3
• Regular imaging is essential to monitor for false lumen expansion or aneurysm formation 1, 2

Indications for Reoperation

Chronic Type A Dissection: 1

• Development of symptoms
• Aortic regurgitation
• Aortic diameter exceeds 5-6 cm

Chronic Type B Dissection: 1

• Development of symptoms
• Progressive aortic enlargement reaching 6.0 cm
• Consider endovascular stenting if anatomy is suitable

Reoperation Risks

• Reoperation rate is approximately 10% at 5 years and up to 40% at 10 years after primary surgery, with even higher risk in Marfan syndrome patients 1, 3
• Repeat sternotomy requires extreme caution as the aorta is usually unprotected by pericardium 1, 3

Special Populations

Pregnant Patients

• Require management by a multidisciplinary team at specialized centers 1, 2
• Use drugs with the lowest teratogenic impact 1, 2