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Difficulty: Very hardCardiothoracic and Vascular Surgery

A 68-year-old man with a history of poorly controlled hypertension is brought to the emergency department due to sudden-onset, severe, tearing interscapular back pain. On arrival, his blood pressure is 215/115 mmHg, and his heart rate is 118/min. He appears diaphoretic and in severe distress. An electrocardiogram shows sinus tachycardia with no ischemic changes. A portable chest radiograph demonstrates a widened mediastinum. The physician strongly suspects an acute aortic dissection. Arrange the following evaluation and management steps in the most appropriate chronological sequence for this patient.

  1. 1Administer an intravenous beta-adrenergic antagonist (e.g., esmolol)
  2. 2Administer an intravenous vasodilator (e.g., nitroprusside)
  3. 3Perform computed tomography angiography (CTA) of the aorta
  4. 4Identify complicated disease status (e.g., renal malperfusion)
  5. 5Perform thoracic endovascular aortic repair (TEVAR)

Answer

The correct chronological sequence is: 1) Administer an intravenous beta-adrenergic antagonist, 2) Administer an intravenous vasodilator, 3) Perform computed tomography angiography of the aorta, 4) Identify complicated disease status, and 5) Perform thoracic endovascular aortic repair.
The management of suspected acute aortic dissection is highly time-sensitive. First, aortic wall shear stress must be minimized using an intravenous beta-blocker to lower the heart rate. Second, if systolic blood pressure remains >120 mmHg, a vasodilator is added. Only after this initial stabilization should the patient undergo CTA to confirm the diagnosis and determine the Stanford classification. Finally, if a Type B dissection is identified and subsequently complicated by end-organ malperfusion or refractory pain, urgent TEVAR is indicated.

Step-by-Step Solution

1
Initiate anti-impulse therapy with an intravenous beta-blocker.
Heart rate and aortic wall shear stress (dP/dt) are rapidly reduced.
Lowering the shear stress is the most critical immediate intervention to prevent further propagation of the intimal tear prior to imaging.
2
Add an intravenous vasodilator.
Systolic blood pressure is safely reduced to a target of 100-120 mmHg.
Vasodilators lower the blood pressure but must strictly follow beta-blockade to prevent compensatory reflex tachycardia.
3
Obtain definitive imaging with a CTA.
The dissection is visualized, confirming the diagnosis and mapping the anatomical extent (Stanford Type B).
Imaging is required to guide definitive management, but the patient must be medically stabilized before leaving the emergency department for the scanner.
4
Monitor for and identify complications.
The Type B dissection is classified as 'complicated' due to evidence of end-organ malperfusion.
The presence of complications dictates the shift from standard medical management to surgical intervention.
5
Intervene surgically with TEVAR.
The false lumen is covered by a stent graft, restoring true lumen flow and resolving the malperfusion.
TEVAR is the standard of care for complicated Stanford Type B aortic dissections.

Key Concept

The sequential management of acute aortic dissection requires immediate medical anti-impulse therapy (beta-blocker first, then vasodilator) prior to diagnostic imaging, followed by TEVAR if complicated Type B disease develops.
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Topics

Cardiothoracic and Vascular Surgery

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