Aortic Dissection: NEET PG Radiology & Clinical Essentials
1. Clinical Presentation
Classic presentation: Sudden onset of “tearing” or “ripping” chest pain radiating to the back (interscapular region). Always consider patients with a history of hypertension or Marfan syndrome.
2. Radiographic Findings
- Widened Mediastinum: The most common, though non-specific, sign on chest X-ray.
- Calcium Sign: Separation of the intimal calcification from the outer soft-tissue border of the aortic wall by >5–10 mm.
- Double Barrel Sign: Visualization of both the true and false lumen on contrast-enhanced CT.
3. Imaging Modalities
| Modality | Clinical Utility |
|---|---|
| CT Angiography (CTA) | Gold standard for diagnosis; rapid, highly sensitive, and provides excellent anatomical detail. |
| Transesophageal Echo (TEE) | Preferred in hemodynamically unstable patients; can be performed at the bedside. |
| MRI | Highly accurate but time-consuming; not suitable for unstable patients. |
4. Management & Classification (Stanford)
- Stanford Type A: Involves the ascending aorta. This is a surgical emergency.
- Stanford Type B: Involves only the descending aorta (distal to the left subclavian artery). Typically managed medically with aggressive blood pressure control (e.g., beta-blockers).
- Key Management Goal: Control heart rate and blood pressure (target systolic BP 100–120 mmHg) to reduce shear stress on the aortic wall.