Chronic Type B Dissections What are the questions?? Current - - PDF document

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Surgical Treatment of Chronic Type B Aortic Dissection: Open Repair is preferred (for treatment of TAAA)

Richard P. Cambria, M.D.

Systems Chief Vascular Services, and Chief of Vascular and Endovascular Surgery, Steward Health Care System and St. Elizabeth Medical Center, Boston MA. Robert R. Linton MD Professor of Vascular and Endovascular Surgery, Harvard Medical School (Emeritus)

Chronic Type B Dissections What are the questions??

• Current Management of TAAA of Chronic

Dissection Etiology

• The Evolving Role of TEVAR in chronic TBD

Treat or prevent aneurysm ?

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Cambria et al. JVS 1988:7

Background

Branch Compromise Aortic + 18/20 (90) 34/38 (89)  NS Rupture - 38/84 (45) 30/178 (17)  p<.0001

J Vasc Surg2016;64:1558-59

The Landscape

• LATE SURVIVAL SIGNIFICANTLY

IMPROVED WITH INTERVENTION VS MEDICAL THERAPY ALONE

• DATA AVAILABLE

AT RISK PATIENTS

• PROSPECTIVE “REAL WORLD” DATA

EMERGING SVS VQI/ FDA PROJECT

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J Vasc Surg2015;61:1192-9

• 298 Type B pts initially RX with Med Rx
• “Failure” defined any death or aortic intervention

Overall in 58% of pts

• @ 6 years survival better (76 vs 58%, p=.01)

in those WITH INTERVENTION

MGH Series

JVASC Surg 2018; 68

• CALIF ADMIN DATABASE STUDY OF 9, 165

PATIENTS WITH uTBAD (2000-10)

• SIGNIFICANT (P<.01) SURVIVAL BENEFIT

FOR TEVAR @ 1 AND 5 YEARS VS. MEDICAL RX ALONE

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• Innovative project to serve as a pilot program for registry-based post-approval

surveillance in collaboration with industry and the FDA

• Determine the effectiveness of TEVAR for treating type B dissection (TBD)
• Describe the project cohort and 30-day outcomes of TEVAR for both acute (AD) and

chronic dissection (CD) patients

Objectives

JVASC Surg 2019: 69; 680

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Chronic TBD in a 30 yr old RN

Anatomy of CTBD in VQI Registry Study

78 %

Proximal DTA Zone Maximal Diameter

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Anatomy of Distal Dissections

Entry tear - distal to left subclavian artery Rupture at entry site is RARE in absence of localized aneurysmal dilatation Anatomic foundation of medical Rx for distal dissections.

Chronic Phase after TBD

• Aneurysmal degeneration of outer

wall false lumen is the principle late complication

• Continued patency of false lumen

flow is demonstrated risk factor anatomic high risk factors

• 40-50% of pts irrespective of

initial surgical vs. medical Rx will require interval aortic resection for aneurysm

Implications for CT surveillance, B- blockade + BP control

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J Vasc Surg2017: 1-7

MGH Data

• 245 pts with uTBD managed medically with

mean f/u of 6.8 yrs!

• 38% required intervention in f/u

PREDICTORS → Entry tear ˃ 10mm (OR 2.1) → Total Ao diameter ˃40mm (OR 2.2) → F lumen diameter ˃ 20 mm

• Complete F lumen thrombosis → protective

Surgery 1982;92(6):118-34

• Delivered as the John Homans’ Lecture at SVS 1982
• 30% of late deaths 2° ruptured aneurysms
• 30% had secondary surgery for chronic aneurysm formation

The Problem Defined

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J Vasc Surg 2015;62:900-6

• 200 pts with initial medical Rx of TBD → mean f/u 5 years!

➢ only 50% free from aortic expansion ➢ Mean annual growth 12.3mm Ao diameter ➢ 28% had intervention (most open) for aneurysm of chronic dissection etiology

Treatment Principles

• Medical therapy is 1

treatment of Type B dissections

Equivalent results surgery (high mortality) [Glover et al. Circulation 1990:82 Supp IV]

• Anatomic goal of eliminating

short and long-term complications could be met with minimally invasive approach to seal entry tear

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ROLE OF UNCOVERED STENTS

ENTRY TEAR DISTAL BARE STENTS REMODEL AORTA Pathology—Specific Stent Graft Construct of Type B Dissection

Coming in 2019!

Chronic Aneurysm The Genuine Challenge for TEVAR

Principles of aneurysm resection apply → more difficult than treatment with TEVAR in acute phase → open surgery

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Why is Open Surgery Preferred ?

Thoracoabdominal Aneurysm of Chronic Dissection Etiology

TAAA of Chronic Dissection Etiology

• Patients often young (mean 64 years)
• Syndromic conditions common (15 % )
• Over past decade 30 % TAAA surgery for

chronic dissection aneurysms

• Durability considerations are VITAL

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J Vasc Surg 2011;53:600-7

• No differences in periop mortality
• No differences in paraplegia (7% vs 5%)

TAA OUTCOMES: EFFECT OF CHRONIC DISSECTION

Years

2 4 6 8 10 12 14 16

% Survival

20 40 60 80 100

Dissection Degenerative

Survival

60% 56% 47% 28%

p=0.049

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J Vasc Surg2011;53:1195-201

Impact of Collateral Network Concept

• Refined techniques for spinal cord protection
• Operative mortality for Extent I-III TAA under 5%

Shift in Spinal Cord Protection

• Support of the cord

collateral network with distal aortic perfusion (LA- femoral Bpass)

• Monitoring of MEVOP

during sequential clamping

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J Vasc Surgery 2013; 58:283-290

Current Results Results - Outcomes

Variable Clamp/Sew (n=385) DAP/MEVOP (n=100) p

Intra-op Death 0.5% 1.0% 0.501 Early Post-op Death 9.9% 4.0% 0.072 Hospital LOS (d) 21.6 + 23.5 19.9 + 12.6 0.492 Permanent SCI 11.9% 3.0% 0.008 Perm SCI/Death 19.1% 7.0% 0.003 ARF with HD 11.4% 5.1% 0.063

Early Post-op Death 9.9% 4.0% 0.072 Permanent SCI 11.9% 3.0% 0.008

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Durability of Open Surgical Repair of Type I-III Thoracoabdominal aortic aneurysm

JVASC Surg April 2019; 1-11

J Vasc Surg 2008;48:828-35

• At 5 years after open operation, permanent

loss of functional capacity occurred rarely

TAA Repair: Late Results

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JVASC Surg Jan 2019; 296-302

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Conclusion

TEVAR FOR TYPE B DISSECTION

• Preferred Rx for Acute Comp TBD
• Evolving Role in uncomplicated TBD shows promise

and being studied

• “Experimental” for Rx of Established TAAA of

chronic dissection Etiology

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