USMLE Prep - Medical Reference Library

Acute Aortic Dissection — HR/BP Control, Imaging, and Surgical vs Medical Management

System: Cardiology • Reviewed: Sep 2, 2025 • Step 1Step 2Step 3

Synopsis:

Tearing chest/back pain with pulse deficits or mediastinal widening suggests dissection. Rapidly control HR (<60) and SBP (100–120) with beta-blockade and vasodilators; obtain CTA chest/abdomen/pelvis. Type A requires emergent surgery; Type B usually medical unless complications warrant TEVAR.

Key Points

  • Use the highest‑yield diagnostic test early; do not let testing delay time‑critical therapy.
  • Set objective targets and reassess frequently.
  • Plan definitive source control or disease‑specific therapy when indicated; document follow‑up and patient education.

Algorithm

  1. Suspect dissection → control HR then BP; obtain emergent imaging.
  2. Type A → emergent surgery; Type B → medical therapy unless rupture, malperfusion, refractory pain/HTN → consider TEVAR.
  3. ICU monitoring and genetic evaluation for aortopathy as indicated.

Clinical Synopsis & Reasoning

Tearing chest/back pain with pulse deficits or mediastinal widening suggests dissection. Rapidly control HR (<60) and SBP (100–120) with beta-blockade and vasodilators; obtain CTA chest/abdomen/pelvis. Type A requires emergent surgery; Type B usually medical unless complications warrant TEVAR.


Treatment Strategy & Disposition

Stabilize ABCs. Initiate guideline‑concordant first‑line therapy with precise dosing and continuous monitoring. Escalate to advanced/procedural interventions based on explicit failure criteria. Define ICU, step‑down, and ward disposition triggers; involve specialty teams early.


Epidemiology / Risk Factors

  • Risk varies by comorbidity and precipitants; see citations for condition‑specific data.

Investigations

TestRole / RationaleTypical FindingsNotes
CTA chest/abdomen/pelvis (or TEE/MRA if unstable/contraindications)DiagnosisIntimal flap, true/false lumenExtent and branch involvement
ECG, troponin, bedside USDifferentialRule out ACS/tamponadeGuide therapy
Labs including type & crossPreparationPotential OR need

High-Risk & Disposition Triggers

TriggerWhy it mattersAction
Type A dissection or malperfusionImmediate mortalityCT surgery emergently; ICU
Refractory pain or hypertensionPropagation riskTight HR/BP control; reassess imaging
Neurologic deficit, mesenteric/renal ischemiaOrgan threatUrgent endovascular/surgical plan
Pregnancy or genetic aortopathyHigh complexityMultidisciplinary care
Suspected rupture/tamponadeImminent deathPericardiocentesis generally avoided; OR now

Pharmacology

Medication/InterventionMechanismOnsetRole in TherapyLimitations
Esmolol or Labetalol IV to HR <60Rate/impulse controlMinutesReduce shear stress firstAdd vasodilator after β-blocker
Nicardipine/Clevidipine IV for SBP 100–120VasodilationMinutesBP target after β-blockadeAvoid reflex tachycardia
Pain control (IV opioids)AnalgesiaMinutesDecrease sympathetic drive

Prognosis / Complications

  • Outcome depends on timeliness of diagnosis and definitive therapy; monitor for complications.

Patient Education / Counseling

  • Provide red‑flag education, adherence guidance, and explicit return precautions; arrange timely specialty follow‑up.

References

  1. AHA/ACC aortic disease guideline — Link