THORACIC AORTIC PATHOLOGY

CHALLENGES AND SOLUTIONS

Thomas C. Naslund, M.D.Vanderbilt University Medical Center

CONFLICT OF INTEREST

WL Gore Investigator, Speaker, ConsultantBoston Scientific ConsultantLeMaitre VascularScientific Advisory Board

OFF LABEL USE

• WL Gore TAG

• Cook Zenith

• WL Gore Excluder

FREQUENTLY SEEN PATHOLOGY

• Aneurysm-fusiform *-saccular (concern for infection)

• Aortic Dissection – Type A* and B• Traumatic transection• Penetrating ulcer• Intramural hematoma

*labeled use for TAG *surgical management

PENETRATING ULCER

INTRAMURAL HEMATOMA

THORACIC AORTIC ANEURYSM

• Atherosclerosis of iliacs– 8-9 mm EI make most TEVAR easy– 7-8 mm EI make some TEVAR difficult– <6 mm EI is a clear danger zone (alternate access)

• Dilation with serial dilators if EI normal• KY jelly helps• Extreme caution with dilators and atherosclerosis

• Tortuosity of iliacs and TA (arch)• Neck

– <2cm in straight distal attachment can work– 2cm with angle in arch will not work

ACCESS FOR THE DISEASED ILIAC

• Conduit– Sutured to the CI artery end to side– Complete TEVAR via conduit– Consider anastomosis to CFA after completion

• May need secondary intervention• CFA may already be exposed/opened/damaged

• Direct CI/Abdominal Aorta Access– Transverse incision over rectus sheath– Retract rectus laterally/RP dissection– CI/terminal aorta easily exposed – Counter puncture in lower quadrant– Direct arterial closure

GOALS OF ENDOVASCULAR MANAGEMENT

Acute Type B Aortic Dissection• Redirect flow into true lumen• Cover entire descending thoracic

aorta• Provide satisfactory visceral flow• Facilitate aortic healing• Avoid surgical repair

DISSECTION TREATMENT ALGORITHM

• Type A- Medical Therapy &Emergency Cardiac Surgery Evaluation

• Type B- Medical therapy» Stent graft for complications in acute phase» Stent graft for aneurysm formation in late follow up» Long term follow up for all Type B to assess aneurysm

formation/stent graft

NECK PROBLEMS/SOLUTIONS

• Big (>36mm) – 45mm TAG in EU

• Small (<23mm)– 18-23mm diameter graft

• Short (< 2cm)– Debranching/fenestration

• Angled (>?)– Specific design/fenestration

LENGTHENING THE NECKCovering Branch Vessels

• Left Subclavian– Consider vertebrobasilar circulation

• Contralateral vertebral/carotid disease • Celiac

– Consider pancreaticoduodenal and gastroduodenal • SMA disease

• Coiling typically not needed– Subclavian for Type II leak

• Transbrachial– Celiac

• Flow robust– Catheterize, cover celiac/trap catheter, coil

SURGICAL DEBRANCHING

• Viscerals– Celiotomy

• Midline gets all 4• Left flank gets 3,maybe 4

• Arch– Left subclavian to carotid transposition– Carotid-carotid bypass (retroesophageal)– Aortoinnominant & carotid bypass

ARCH REPAIR

TRAUMATIC TRANSECTION

• Deceleration injury–MVA –falls

• Sudden movement of aortic arch

• Circumferential tear of arterial intima and media

• Survivors have intact adventitia and possibly some media

TRAUMATIC TRANSECTION

• Innominate artery second most common site

VANDERBILT SERIESOpen Repair 1987

• 41 Patients• 5 Died without repair

– 3 preoperatively– 2 en route with emergency thoracotomy

• 5/36 Repaired died during operation– 3/5 associated with aortic clamping

• 2/36 Paraparesis

TRANSECTION PRE OP MEDICAL MANAGEMENT

• Beta Blockade• BP/HR control• Discontinue after repair

STENT GRAFT REPAIR OF TRAUMATIC TRANSECTION

n = 20

• Since 2005• Age 35 (15 – 72)• Mortality 1/20 (5%) – 72 yo MSOF

STENT GRAFT REPAIR OF TRAUMATIC TRANSECTION

n = 20• Mean procedure time 103min• Mean blood loss 390ml• Mean intraoperative transfusion 1 unit• Grafts utilized

– TAG - 9– Cook Iliac extenders- 9– Excluder aortic cuffs - 2

STENT GRAFT REPAIR OF TRAUMATIC TRANSECTION

n = 20

• Technical success 100%– graft exclusion of injured

segment– No deaths pre operatively

• Operative complications– groin access site – 2– TAG graft collapse – 2

– spinal cord injury – 0– dialysis – 0

LATE FOLLOW UP

• Erosions – 0• Endoleaks/aneurysm – 0• Access site false aneurysm – 0• Paraplegia – 0• Secondary interventions – 0

USE OF COOK ILIAC LIMB EXTENDER

• Aorta diameter too small for TAG prosthesis (<23mm)

• 55 mm length (satisfactorily covers entire area of injury)

• Z stent design (no collapse)• Requires manual loading into long sheath to

reach aortic arch

ZENITH Delivery and Deployment

USE OF ABDOMINAL AORTIC CUFF EXTENDERS

• 33 – 36 mm length• Reported in several series with success• Requires 3 or more individual cuffs to bridge

injured region• Requires inventory of substantial numbers of

aortic cuffs• Cook, Medtronic, and Gore

TIGHT ARCH

• Typical of adolescence and young adults

• Implant can either poorly oppose the inner arch and collapse

FOLLOW UP• Interval CT in 1 – 3

days (renal function considerations)

• Follow up CT 1 -3 months after discharge

• Annual CT • Eventually CT each 3-5

years • Emphasis on permanent

life-long follow up

LATE CONCERNS

• Erosion

• False aneurysm formation

• Infections

MINIMAL AORTIC INJURY

• Focal-non-circumferential intimal disruption• No false aneurysm• No periaortic hematoma• Suitable for medical therapy and CT follow up

rather than intervention– Healing typical in 3-6 months– Persistent fixed lesions identified after 1 year

followup