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Difficulty: MediumCardiovascular System

A 62-year-old man is brought to the emergency department complaining of sudden-onset, severe, tearing chest pain that radiates to his back. His blood pressure is 210/115 mm Hg in the right arm and 170/95 mm Hg in the left arm. His pulse is 115/min and regular. Physical examination reveals a new decrescendo diastolic murmur at the right upper sternal border. An electrocardiogram shows non-specific ST-segment changes. Arrange the following steps in the most appropriate sequential order for the evaluation and management of this patient.

  1. 1Administer intravenous esmolol
  2. 2Administer intravenous nitroprusside
  3. 3Perform computed tomography angiography of the aorta
  4. 4Consult cardiothoracic surgery for emergent repair

Answer

The correct sequence for managing suspected acute aortic dissection is to first control heart rate with a beta-blocker, then control blood pressure with a vasodilator, followed by definitive imaging, and finally surgical consultation.
The correct sequence prioritizes preventing the propagation of the dissection flap. Intravenous beta-blockers must be given first to decrease the heart rate and left ventricular contractility (reducing dP/dtdP/dt). Only after the heart rate is controlled should vasodilators be added to reach a target systolic blood pressure of 100-120 mm Hg. Once hemodynamically stabilized, definitive imaging (CT angiography) is performed, which then guides the need for emergent surgical repair.

Step-by-Step Solution

1
Recognize the clinical presentation of acute aortic dissection.
The tearing chest pain, asymmetric blood pressures, and new aortic regurgitation murmur strongly suggest an ascending (Type A) aortic dissection.
Accurate initial recognition guides the immediate necessity of strict hemodynamic control prior to other interventions.
2
Select the initial pharmacological intervention.
Intravenous esmolol (a beta-blocker) is administered first.
Decreasing the heart rate and left ventricular contractility reduces aortic wall shear stress and prevents propagation of the dissection flap.
3
Select the subsequent pharmacological step.
Intravenous nitroprusside is administered next.
Vasodilators further lower blood pressure but must strictly be given after beta-blockade to prevent reflex tachycardia.
4
Identify the appropriate diagnostic imaging.
Computed tomography angiography of the aorta is performed.
Imaging definitively confirms the diagnosis and anatomical extent (Stanford type A vs. B) after hemodynamics are stabilized.
5
Determine the definitive treatment.
Cardiothoracic surgery consultation is obtained.
Ascending aortic dissections require immediate operative intervention to prevent rupture and mortality.

Key Concept

In the acute management of suspected aortic dissection, sequential hemodynamic control requires the administration of an intravenous beta-blocker to reduce heart rate and shear stress before using a vasodilator to lower blood pressure.
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Topics

Cardiovascular System

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