How to manage visceral vessels originating from the false lumen during a Thoracic Endovascular Aortic Repair (TEVAR) procedure?

Managing Visceral Vessels Originating from the False Lumen During TEVAR

Before you place your TEVAR stent, you must figure out which "pipe" (true lumen or false lumen) is feeding blood to the belly organs—if they're fed by the false lumen, simply covering the tear will cut off their blood supply and cause organ death, so you need special techniques to keep them alive. 1

Think of It Like This (Simple Version)

Imagine the aorta is like a garden hose that splits into two channels after it tears—a "real" channel (true lumen) and a "fake" channel (false lumen). Sometimes the pipes going to your stomach, intestines, and kidneys branch off from the fake channel instead of the real one. If you just seal off the fake channel without thinking, those organs will die because they lose their blood supply. 2

Step 1: Map Out Where Blood Is Coming From

Before doing anything, get a CT scan with contrast (CTA) to draw a map showing which belly organs get blood from which channel. 1 This is like checking which rooms in a house are connected to which electrical circuit before you flip the breaker. You need to see:

• Which visceral vessels (celiac artery, superior mesenteric artery, renal arteries) come off the true lumen 2
• Which come off the false lumen 2, 1
• Whether the true lumen is squished or wide open 3

Step 2: Check for Emergency Signs

Look for signs that organs are already dying (called "malperfusion syndrome"): 1

• Severe belly pain that won't stop
• Blood lactate levels going up (means tissues aren't getting oxygen)
• Kidneys suddenly failing
• Legs turning cold or painful

If any of these are present, this is an emergency requiring immediate intervention. 1

Step 3: Choose Your Strategy Based on the Map

Option A: If Visceral Vessels Come from TRUE Lumen

You can do standard TEVAR—just cover the entry tear in the thoracic aorta, which will cause the false lumen to clot off over time. 2 This is the easy scenario.

Option B: If Visceral Vessels Come from FALSE Lumen

You CANNOT just cover the tear and walk away—you'll kill the patient. 1 Instead, use one of these rescue techniques:

Technique 1: Stent the At-Risk Vessels First (Preventive Stenting)

• Before or during TEVAR, place stents from the true lumen into the origins of the visceral vessels that are at risk 2, 1
• This creates a new pathway for blood to reach those organs even after you seal the false lumen 2
• Use balloon-expandable stents (like Palmaz stents) for precise placement just above critical branches like the superior mesenteric or renal arteries 2

Technique 2: Create a Fenestration (Make a New Hole)

• Use a balloon to punch a hole (fenestration) between the true and false lumen downstream from where you'll place the TEVAR stent 2, 1
• This keeps the false lumen pressurized so blood can still reach the organs fed by it 2
• Success rate is over 90% for restoring flow to blocked vessels 1
• Sometimes you need to place a stent across this new hole to keep it open, especially in chronic dissections where the tissue is scarred 2

Technique 3: Intentional False Lumen TEVAR (Rare, Last Resort)

• In very rare cases where the true lumen is completely collapsed or slit-like, you might intentionally place the TEVAR stent in the false lumen to exclude an aneurysm while preserving visceral flow 4, 5
• This is only appropriate when recanalization of the true lumen has failed and the patient is too sick for open surgery 4
• You may need to create additional fenestrations to ensure kidneys and other organs stay perfused 5

Critical Pitfalls to Avoid

Pitfall #1: Accidentally Stenting the False Lumen

This is a catastrophic error that causes immediate organ death. 6, 7 To prevent this:

• Always confirm your guidewire is in the true lumen continuously from the femoral artery all the way to the ascending aorta before deploying anything 6
• Use subtraction angiography to verify wire position 6
• After TEVAR deployment, immediately do completion angiography to confirm all visceral vessels are still perfusing 6

If you accidentally stent the false lumen, you have minutes to hours to fix it: 6, 7

• Perform emergency retrograde fenestration from true to false lumen 6, 7
• Extend a stent ("snorkel") across the dissection membrane to re-expand the true lumen 6
• Even with immediate correction, mortality remains very high 6

Pitfall #2: Not Recognizing Dynamic vs. Static Obstruction

• Static obstruction: The vessel origin is physically covered by the dissection flap—treat with stenting across the vessel origin 2, 1
• Dynamic obstruction: The flap moves and intermittently blocks flow—treat with fenestration to equalize pressures between lumens 2, 1
• Misidentifying the type leads to wrong treatment and organ death 1

Pitfall #3: Creating Too Large a Distal Fenestration

While fenestration can save organs, making the hole too big keeps the false lumen pressurized long-term, which promotes aneurysm formation and eventual rupture. 2 The goal is to create just enough communication to prevent acute organ death, not to permanently equalize the two channels.

Post-Procedure Monitoring

After any TEVAR involving false lumen considerations: 2

• Get immediate post-procedure CTA to confirm all visceral vessels are perfusing
• Watch for signs of organ ischemia in the first 24-48 hours (this is when complications declare themselves) 6
• Follow-up imaging at 1 month, 6 months, 12 months, then annually 2
• Look for favorable remodeling: true lumen expanding, false lumen shrinking and clotting off 2

When to Call for Backup

Immediately involve vascular surgery and interventional radiology for technical planning when visceral vessels originate from the false lumen. 1 This is not a case to handle alone—the technical complexity and mortality risk are too high. Have cardiac surgery on standby in case retrograde type A dissection develops during the procedure. 1