Aortic Dissection: Impulse Control

• Tearing pain with a pulse deficit or wide mediastinum → CTA; FIRST β-block (esmolol/labetalol, HR <60) and only then vasodilate to SBP 100–120.
• Type A (any ascending) = emergency surgery; type B = medical unless malperfusion/rupture → TEVAR.
• Never thrombolyse this 'STEMI' mimic, and never vasodilate before β-blockade.
• An interarm SBP difference >20 mmHg or a new AR murmur increases pretest probability.

Workup of Aortic Dissection

• STEP 1 — Consider acute AoD in any patient with: chest, back, or abdominal pain · syncope · perfusion-deficit symptoms (CNS, mesenteric, myocardial, or limb ischemia)
• STEP 2 — Bedside pretest risk assessment for acute AD: ① High-risk conditions: known thoracic aortic aneurysm · Marfan syndrome · known aortic valve disease · family history of aortic disease · recent aortic manipulation
• ② High-risk pain features: chest, back, or abdominal pain that is ripping or tearing · severe in intensity · abrupt in onset
• ③ High-risk exam features: perfusion deficit (pulse deficit · systolic BP differential · focal neurologic deficit with pain) · aortic insufficiency murmur (new, or not known to be old, with pain) · hypotension or shock
• Determine pretest risk: count of categories containing any single risk factor (ADD risk score 0–3)
• STEP 3 — Diagnostic evaluation guided by risk
• ADD risk score?
• SCORE 0 (no high-risk features): diagnostic evaluation as the presentation indicates
• Alternative diagnosis found?
• Start appropriate therapy
• Hypotension unexplained, or widened mediastinum on CXR?
• Expedited aortic imaging
• Consider aortic imaging for AoD per clinical scenario (advanced age, aortic disease risk factors, or syncope)
• SCORE 1 (any single high-risk category): ECG consistent with STEMI? — Yes: likely primary ACS; absent other perfusion deficits strongly consider immediate coronary reperfusion; if coronary angiography shows NO culprit lesion → expedited aortic imaging. No: CXR with clear alternate diagnosis? — Yes: initiate appropriate therapy. No: history and exam strongly suggesting a specific alternate diagnosis → confirm with further testing (confirmed → appropriate therapy; not → expedited aortic imaging); otherwise → expedited aortic imaging
• SCORE 2–3 (two or three high-risk categories): immediate surgical consultation plus expedited aortic imaging
• Image the entire aorta, chest to pelvis: TEE (preferred if clinically unstable) · CT · MRI
• STEP 4 — AoD present?
• Go to treatment pathway (→ Pathway 19.2)
• High clinical suspicion of aortic dissection → consider a secondary imaging study

Treating Aortic Dissection

• STEP 1 — Acute AoD management pathway: arrange definitive management — appropriate surgical consultation · interfacility transfer if indicated by institutional capabilities (start aggressive medical management until transfer if required)
• STEP 2 — Obtain accurate blood pressure before treatment: measure both arms; base goals on the highest reading
• Hypotension or shock?
• TYPE A dissection: ① urgent surgical consultation + expedited operative management · ② IV fluid bolus — titrate to MAP 70 mm Hg or euvolemia (still hypotensive → start IV vasopressors) · ③ review imaging for pericardial tamponade, contained rupture, severe aortic insufficiency
• TYPE B dissection: ① IV fluid bolus — titrate to MAP 70 mm Hg or euvolemia (still hypotensive → start IV vasopressors) · ② evaluate hypotension etiology — review imaging for contained rupture, consider TTE for cardiac function · ③ urgent surgical consultation
• Hypotension etiology amenable to operative management?
• Manage operatively or interventionally
• Ongoing medical management: close hemodynamic monitoring; hold systolic BP <120 mm Hg (lowest BP preserving end-organ perfusion)
• IV rate and pressure control: ① IV beta blockade (or labetalol; if beta blockade contraindicated substitute diltiazem or verapamil) — titrate to heart rate <60 · ② pain control — IV opiates, titrated to pain control
• Systolic BP >120 mm Hg?
• Secondary pressure control: IV vasodilator — titrate to BP <120 mm Hg (goal: lowest BP preserving adequate end-organ perfusion)
• Ascending aorta involved?
• Manage with surgery or intervention
• Continued medical management: close hemodynamic monitoring; hold systolic BP <120 mm Hg (the lowest BP still maintaining end-organ perfusion)
• STEP 3 — Complications needing operative/interventional management? Malperfusion syndrome · dissection progression · aneurysm expansion · uncontrolled hypertension → Yes: operative/interventional management
• STEP 4 — No complications: switch to oral medications (beta blockade/antihypertensive regimen); outpatient surveillance imaging