1. Management of acute type b aortic dissection
นพ.อรรถภูมิ สู่ศุภอรรถ
รพ.ราชวิถี

2. COMPLICATIONS IN ACUTE TYPE B AORTIC DISSECTION
No uniform criteria to define “complicated”
15-20% of cases
Impending rupture
Malperfusion syndrome (10%)
Hemodynamic instability (15%)
Refractory hypertension
Refractory hypertension (hypertension persisting despite 3 different classes of antihypertensive therapy at maximal recommended or maximal tolerated doses)

3. Malperfusion syndromes
About 10% of patients with type B aortic dissection
Dynamic malperfusion caused by branch vessel occlusion of the true lumen by the pressurized false lumens
Static malperfusion caused by propagation of the dissection into branch vessel ostia with distal vessel occlusion

4. Malperfusion syndromes
Mesenteric ischemia
abdominal pain, nausea, and diarrhea
associated with an increase in laboratory markers (bilirubin, amylases, hepatic, and intestinal enzymes).
Highly devastating and has a major impact on early mortality
Lower limb ischemia
Relatively benign and surgical intervention should be performed in symptomatic patient.
Spinal cord ischemia
paraparesis or paraplegia

5. Strategy Central Aortic Repair Peripheral repair Aortic Replacement
Fenestration
Endograft
Re-entry fenestration
Peripheral repair
Graft Bypass
Stenting
Therapeutic Aim
To restore the perfusion of the organs
To stop/limit the dissecting process to protect the organs

6. A 59-year-old male with history of hypertension and COPD presented with abdominal pain, painful, pulseless right lower extremity TL TL

7. Celiac a. TL TL
Rt CIA FL
Lt RA
Rt RA

8. Stent-graft placement

9. IVUS/ TEE superior to angiography for identifying
Primary and distal reentry tears
Documenting guidewire position in the true lumen
Assessing seal zones
Detecting endoleaks
assessment of the ascending aorta to be mandatory at the conclusion of each TEVAR case to assess for retrograde ascending aortic dissection
Circulation. 2005;112:I260-4.

10. Stent placement Uncovered stents improve flow
inadequate relief of dynamic obstruction after surgery
static obstruction of abdominal aortic branch vessels, which is typically unaffected by proximal aortic stent- graft treatment and fenestration.
The use of uncovered stents in the aorta and side branches may improve flow in aortic dissection (Figure 4). The most common indications include (1) inadequate relief of dynamic obstruction after surgery, stent-graft treatment, or fenestration and (2) static obstruction of abdominal aortic branch vessels, which is typically unaffected by proximal aortic stent-graft treatment and fenestration.
In most cases of symptomatic static branch-vessel compromise, attempts are made to restore more normal flow dynamics by placing an uncovered stent via the aortic true lumen into the true lumen of the involved branch.

12. impending rupture/Rupture
Persistent pain despite good blood pressure control
Aortic dissection with persistent uncontrolled hypertension
Evidence of dissection progression despite optimal medical management.
An increase in perioaortic hematoma and hemorrhagic pleural effusion in 2 subsequent CT examinations
Requires sealing off the primary tear as well as the site of the leak
Frequently necessitates paving the entire thoracic aorta when the site of the leak is unclear.
J Am Coll Cardiol Intv 2008;1:395– 402.
Circulation 2010;122:1283–9.

13. Refractory hypertension
International Registry of Acute Aortic Dissection (IRAD) trial data showed that in-hospital mortality after medical management was significantly increased in average-risk patients with type B aortic dissection under medical therapy with refractory hypertension/pain compared with those without these features (35.6% vs. 1.5%; p )
Circulation 2010;122:1283–9.

14. Open surgery

16. Uncomplicated Acute type B aortic dissection
Medical management
Anti-impulse therapy
uncomplicated dissection
lack of appropriate facilities
presence of comorbidities or morphology that made open surgery or TEVAR not feasible
IRAD: 3-yr survival = 78%
Late aortic-related complications= 25-50%

17. Prophylactic TEVAR?
Thrombosed false lumen predicts lower event rates after type B dissection
Randomized comparison of strategies for type B aortic dissection: the INvestigation of STEnt Grafts in Aortic Dissection (INSTEAD) trial
Found no difference in the primary end point of all-cause mortality at 2 years
Thoracic false lumen thrombosis, TEVAR> Medical Mx :91.3%VS 19.4% (P < .001)
high rate of aorta-related deaths in the TEVAR group resulting from periprocedural technical complications
Circulation. 1993;87:
Circulation. 2009;120:

18. High-risk features of uncomplicated type b dissection
Initial aortic diameter ≥ 4.0 cm with patent false lumen *,€,ɸ
Initial false lumen diameter ≥ 22 mm in proximal DTA ∞
IMH with PAU in proximal DTA *,ɸ
* Eur J Vasc Endovasc Surg.2006;32:
€ J Thorac Cardiovasc Surg. 2007;134:
ɸ Circulation. 2010;122: S74-80.
∞J Am Coll Cardiol. 2007;50:

19. Long-Term Management
Specific predictors of follow-up mortality include
Female gender
Prior aortic aneurysm
Atherosclerosis
Pleural effusion
In-hospital acute renal failure
Hypotension or shock
β-blockade & blood pressure control
IRAD: calcium channel blockers at discharge was associated with improved long-term survival selectively in medically treated type B dissection patients
>1/3 of patients will require surgery for aortic-related complications within 5 years of the initial dissection
Serial imaging at 1, 3, 6, and 12 months after discharge, and annually

20. OUTCOME DATA FROM MEDICAL THERAPY
Early mortality rate = 6.4% (95% CI: 5.1% to 7.9%)
Stroke = 4.2% (95% CI:2.3% to 7.4%)
spinal cord ischemia = 5.3% (95% CI: 3.4% to 8.4%)
5-year survival rates ranged from 70.2% to 89%
Aortic adverse event freedom (including aortic death, rupture, new dissection, enlargement, reintervention) ranged from 75% to 88.5% at 5 years, but there were variable event definitions among studies
combined early neurological complication event rate of 10.1% (95% CI: 7.5% to 13.5%)

21. OUTCOME DATA FROM TEVAR
in most of the papers, indication for TEVAR was complicated acute type B dissection
criteria for defining complicated were variable
Early mortality rate =10.2% (95%CI: 9.0% to 11.6%)
Stroke = 4.9% (95% CI: 4.0% to6.0%)
Spinal cord ischemia = 4.2.% (95% CI: 3.3% to 5.2%)
5-year survival rates ranged from 56.3% to 87%
Freedom from aortic events ranged from 45% to 77% at 5 years.

22. OUTCOME DATA FROM OPEN SURGERY
Early mortality rate = 17.5% (95% CI: 15.6% to 19.6%)
Stroke = 5.9% (95% CI: 4.8% to 7.3%)
Spinal cord ischemia = 3.3%(95% CI: 2.4% to 4.5%)
5-year survival rates ranged from 44% to 64.8%
Freedom from aortic events ranged from 58.7% to 68% at 5 years.

23. MEDICAL THERAPY VS TEVAR AND OPEN SURGERY VERSUS TEVAR
invalidated by unbalanced populations (unmatched illness conditions and rates of complicated vs. uncomplicated cases of patients assigned to each treatment).
Complicated cases Open Sx, TEVAR
uncomplicated cases Medical treatment

24. Comparison of Early (30 Days/In-Hospital) Outcomes With Medical Therapy and TEVAR in Acute Type B Aortic Dissections

27. Subacute type B aortic dissection
Very limited outcome data
INSTEAD (Investigation of Stent Grafts in Aortic Dissection) trial
Primary success rate = 95.7%
Early mortality = 2.8%
Stroke rate =1.4%
Spinal ischemia= 2.9%
Required secondary procedures = 18%

28. VIRTUE (VALIANT Thoracic Stent Graft Evaluation For the Treatment of Descending Thoracic Aortic Dissections- Post Marketing Surveillance Registry) Registry
24 patients with complicated subacute type B aortic dissections treated with TEVAR
Primary procedural success rate= 100%
Early mortality rate =1.8%
Late deaths = 0%
Strokes or cases of spinal cord ischemia = 0%
Negative prognosis in the subacute phase
Change in aortic morphology (expanding diameter 4 mm, new onset of periaortic hematoma, and/or pleural hemorrhagic effusion)
Refractory hypertension
Recurrent thoracic pain
Malperfusion

29. Subacute type B aortic dissection