AKT · Cardiovascular/Vessels, aorta & venous

Aortic dissection

Intimal tear → blood tracks into the aortic media creating a false lumen

Overview

A tear in the aortic intima lets blood split the media, creating a false lumen. Stanford type A involves the ascending aorta (surgical emergency); type B is distal to the left subclavian (usually managed medically). It presents with sudden tearing chest/back pain and pulse/BP asymmetry; complications follow the branches it occludes (stroke, MI, tamponade, limb/visceral ischaemia).

Recognise

Sudden, severe, tearing/ripping chest pain radiating to the back (interscapular); may migrate as the dissection extends
Pulse deficit or >20 mmHg BP difference between arms; new aortic regurgitation murmur; hypertension or shock
Branch involvement: stroke, syncope, MI (right coronary), tamponade, paraplegia, acute limb/mesenteric/renal ischaemia

Red flags

Type A dissection (ascending aorta) → emergency cardiothoracic surgery
Tamponade, acute AR, or malperfusion → life-threatening complications; anticoagulation/thrombolysis would be catastrophic if mistaken for ACS

Differentials & how to tell them apart

Acute coronary syndrometerritorial ECG/troponin; but giving antiplatelets/thrombolysis in dissection is dangerous — check for asymmetry/back pain

Pulmonary embolismpleuritic pain, hypoxia, RV strain

Musculoskeletal/oesophageal painno haemodynamic or pulse abnormality

Aortic dissection — intimal flap on contrast-enhanced CT
James Heilman, MD / CC BY-SA 3.0 — Wikimedia Commons

Investigations

CT angiogram of the aorta is the diagnostic test (TOE if too unstable to move); ECG (may mimic/coexist with inferior MI); CXR (widened mediastinum); cross-match; controlled imaging only if stable.

Management

Rate/BP control (IV beta-blocker); type A → emergency surgery, type B → medical management

1Suspect from tearing pain + pulse/BP asymmetry; diagnose with CT aortogram. Control shear force with an IV beta-blocker (rate then BP) and give analgesia.Gate: Type A (ascending aorta) → emergency cardiothoracic surgery. Do NOT treat as ACS — antiplatelets/thrombolysis can be fatal in dissection.
2Type B (distal) → medical management with strict BP/HR control; endovascular or surgical repair if complicated by malperfusion, rupture or refractory pain.

IV beta-blocker (e.g. labetalol) to control heart rate and BP — reduce shear force (dP/dt) — target HR ~60 and systolic ~100–120; add a vasodilator after rate control

Type A → emergency surgical repair — replace the ascending aorta; do not delay

Type B → medical management (strict BP/HR control) — endovascular/surgical repair if complicated (malperfusion, rupture, refractory pain)

Analgesia — opioids; avoid anything that would be given for ACS by mistake

Key points

Sudden tearing chest pain to the back + >20 mmHg inter-arm BP difference/pulse deficit ± new AR murmur = aortic dissection → CT aortogram, IV beta-blocker to drop shear force. Type A = surgery; type B = medical. Mistaking it for ACS and anticoagulating is catastrophic.

Monitor & prognosis

Continuous BP/HR, serial imaging of the false lumen, complication surveillance.

Type A: very high mortality without surgery; type B better with BP control.

Source: ESC aortic disease; cross-ref acute_care