Variability in the Treatment of High-Risk Type B Aortic Dissection at a Single Center.

Although there are established high-risk features in acute type B aortic dissection (TBAD), its management is variable. This study characterizes complicated, uncomplicated, and high-risk TBAD in addition to their management and outcomes to gain insight into the actual significance of these high-risk features and the reality of real-world practice in managing TBAD. A retrospective review of 62 patients was conducted. Patient demographics, management, and outcomes were characterized and evaluated with Pearson's χ2 test, Fisher's exact test, or analysis of variance. Of the 32 high-risk TBADs, 66% (n = 21) received endovascular repair, 31% (n = 10) were medically managed, and 3% (n = 1) received hybrid (open and endovascular) repair. Refractory hypertension and pain (52%, n = 11) were the most common high-risk features in patients with high-risk TBAD who received endovascular repair. A maximum aortic diameter of >40 mm (67%, n = 6) was the most common high-risk feature in patients who received medical management. The most prevalent high-risk feature for all treatment groups in the high-risk TBADs was an aortic diameter of >40 mm (n = 16; 50%). Adverse postoperative outcomes were highest in the high-risk and complicated groups with endoleak as the most common adverse outcome (high-risk 12.9%, complicated 13.6%). Of the 62 patients, 47% (n = 26) had follow-up since their admission with an average follow-up time of 69 ± 166 days. The significance of high-risk features in the management of high-risk TBAD remains unclear. This single-center experience with managing acute TBAD reveals the reality of inadequate follow-up that may be specific to this disease process. This highlights a need to direct more efforts to assess long-term outcomes after treatment.

A rare case of an acute type B aortic dissection contained infrarenal rupture of the false lumen after prior endovascular abdominal aneurysm repair.

New-onset acute type B aortic dissection after prior endovascular aneurysm repair is extremely rare. Extension of an aortic dissection can cause destabilization of the previously implanted stent graft, thrombosis of the stent graft, and rupture of the aneurysmal sac, with high mortality without therapy. This report describes the case of a 66-year-old patient complaining of sudden abdominal pain radiating to both flanks. Computed tomography angiography of the aorta revealed acute type B aortic dissection with infrarenal rupture of the false lumen after endovascular abdominal aneurysm repair 5 years prior. The patient underwent infrarenal open surgical conversion with suprarenal aortic clamping and implantation of a bifurcated Dacron graft. Postoperatively, no serious complications resulted from the treatment, except for fascial dehiscence. In such cases, the patients can be treated in an emergency situation with open repair, despite the high risk of complications and mortality.

Management of Acute, Uncomplicated Type B Aortic Dissection.

For decades, the mainstay of management for acute, uncomplicated type B aortic dissection (TBAD) has been anti-impulse medical therapy, focusing on close control of blood pressure, and heart rate. However, the natural history of this entity has remained one of aortic degeneration over time and significant morbidity and mortality. More recently, the advent of endovascular therapy has driven a revolution in the management of TBAD. While thoracic endovascular aortic repair (TEVAR) was rapidly adopted for the treatment of complicated type B aortic dissection due to significantly improved morbidity and mortality when compared with tradition open surgical techniques, its role in the management of uncomplicated dissection remained controversial. However, the accumulation of favorable data on aortic remodeling and survival following early TEVAR for uncomplicated dissection is driving a shift in paradigm and practice. This is particularly true of patients exhibiting certain features at the time of presentation that are associated with increased risk of failure of optimal medical therapy. This article reviews the current evidence in the literature addressing TEVAR for acute, uncomplicated TBAD. In addition, it presents the state of the art in FDA-approved thoracic endograft platforms, guidance regarding case planning, and step-by-step procedural description, including the management of common challenges, and complications.

Thoracic endovascular repair for acute complicated type B aortic dissections.

OBJECTIVE: This study retrospectively assessed in-hospital mortality and long-term results of emergency thoracic endovascular aortic repair (TEVAR) for patients with life-threatening acute complicated type B aortic dissection (acTBD). METHODS: Between March 2001 and December 2016, there were 55 patients (40 male; median age, 52 ± 13 years) with an acTBD who were treated with TEVAR for malperfusion (58%), aortic rupture (18%), or persistent untreatable pain with true lumen reduction or rapid aortic diameter enlargement (24%) as a sign of disease progression. The patients were categorized according to clinical appearance into two groups: group A, malperfusion, pending rupture, or rupture; and group B, persistent ongoing pain, rapid enlargement of aortic diameter, or significant changes in the true to false lumen ratio. Four patients (7%) had undergone previous aortic surgery. RESULTS: Technical success (coverage of the primary intimal tear) was achieved in 50 patients (91%). The overall in-hospital mortality rate was 9% (n = 5), and there was a statistically significant difference in early mortality between group A and group B (7% vs 2%; P < .02). Causes of in-hospital death were all aorta related, including a rupture during the procedure and on the first postinterventional day in two patients and redissection (ascending aorta, n = 2; descending aorta, n = 1) with a consequent aortic rupture after TEVAR in the remaining three. Permanent neurologic dysfunction occurred in five patients (stroke, n = 2; paraplegia, n = 3). Overall, 19 patients (34%) developed early endoleaks (type IA, n = 5; type IB, n = 11; type II, n = 2; type IB plus type II, n = 1). Therefore, 5 patients needed early (within 30 days) endovascular intervention because of a type IA (n = 2), type IB (n = 3), or type II endoleak (n = 1) and the rapid progression of aortic diameter, persistent signs of ischemia (n = 2), or rupture (n = 1), whereas the remaining 14 patients were treated conservatively and followed up by computed tomography angiography. Seven patients with early endoleaks needed an endovascular intervention (n = 3) or conventional surgery (n = 4) because of aortic progression in the follow-up period (mean interval after procedure, 92 ± 56 months). The actual survival rates were 87%, 85%, and 75% at 1 year, 2 years, and 5 years, respectively, and freedom from aorta-related death was 87%, 87%, and 77% at 1 year, 2 years, and 5 years, respectively. Freedom from reintervention for any cause using a Kaplan-Meier analysis was 70%, 68%, 68%, and 63% at 6 months, 1 year, 2 years, and 5 years, respectively. CONCLUSIONS: TEVAR of acTBD has been proven to be an excellent treatment modality in this cohort of high-risk patients, with promising midterm and long-term results.

Stented elephant trunk procedure with left subclavian artery transposition for acute type B dissection with distal arch involvement.

OBJECTIVE: Complete or partial supra-aortic debranching, after thoracic endovascular aortic repair, is appealing treatment for complicated acute type B dissection (ABAD) with aortic arch involvement (AAI) because of reduced surgical trauma. However, unsatisfactory outcomes have been reported. We retrospectively reviewed our experience of left subclavian artery (LSCA) transposition with stented elephant trunk (SET) implantation for complicated ABAD with distal AAI. METHODS: From April 2011 to December 2014, 19 patients (all men; mean age: 44 years) who had complicated ABAD and distal AAI underwent LSCA transposition with SET implantation via a median sternotomy under hypothermic cardiopulmonary bypass with selective cerebral perfusion. Preoperative renal dysfunction was observed in 3 patients, visceral ischemia in 2 patients, and lower-limb ischemia in 1 patient. RESULTS: No in-hospital deaths occurred. Seventeen patients required mechanical ventilation for <24 hours, and 2 cases for <48 hours. The mean time of mechanical ventilation and duration of stay in the intensive care unit was 18 ± 6 hours and 44 ± 16 hours, respectively. Ischemia of the viscera and lower limbs after surgery was ameliorated. Continuous renal replacement therapy was not required in 3 patients who had preoperative renal dysfunction. Complete thrombosis of the false lumen at the distal end of the SET was observed in 17 of 18 (94.4%) patients during follow-up. CONCLUSIONS: This method preserves autologous brachiocephalic vessels, excludes the false lumen, promotes thrombosis and remodeling of the distal aorta, and repairs proximal aortic lesions simultaneously. Satisfactory surgical outcomes and follow-up results were achieved using LSCA transposition with SET implantation.

Endovascular vs. open repair of complicated acute type B aortic dissections.

Purpose : To assess the comparative effectiveness of thoracic endovascular aortic repair (TEVAR) vs. open surgical repair (OSR) of complicated acute type B aortic dissections (cABAD) using decision analysis. Methods : A decision analysis comparing TEVAR and OSR for cABAD included variables extracted from the best-available evidence. Main outcomes were quality-adjusted life years (QALYs), presented with the 95% credibility intervals (CI), and number of reinterventions over the remaining lifetime. Different clinical scenarios, including age, gender, and risk profile were analyzed. Parameter uncertainty was analyzed using probabilistic sensitivity analysis. Results : In the reference case, a cohort of 55-year-old men, TEVAR was preferred over OSR: 7.07 QALYs (95% CI 6.77 to 7.38) vs. 6.34 QALYs (95% CI 6.04 to 6.66) for OSR. The difference of 0.73 QALYs (95% CI 0.29 to 1.17) is equal to 8.5 months in perfect health. TEVAR was more effective in all analyzed cases and age groups. Perioperative mortality was the most important variable affecting the difference between OSR and TEVAR, followed by the relative risk and percentage of aortic-related complications. Total expected reinterventions were 0.43/patient (TEVAR) and 0.35/patient (OSR). Conclusion : The results of this decision model for the treatment of cABAD suggest that TEVAR is preferred over OSR. Although a higher number of reinterventions is expected, the total effectiveness of TEVAR is higher for all age groups. OSR should be reserved for patients whose aortic anatomy is unsuitable for endovascular repair.

A single stage hybrid repair of a complicated acute type B dissection with aortic arch involvement.

We present a case in which a single stage hybrid repair was successfully for a complicated acute type B dissection of the aortic arch involvement in a 63-year-old male patient. We performed a combination of different techniques; left subclavian artery debranching, elephant trunk insertion without aortic arch replacement, and thoracic endovascular aortic repair (TEVAR) from antegrade approach. The postoperative course was successful, and the patient was discharged on day 11 after surgery. A-half-year's follow up computed tomography (CT) scan showed shrinkage of thrombus lumen, vascular reverse remodeling.

Emergent treatment of aortic rupture in acute type B dissection.

Massive left hemothorax is a rare and dramatic complication of acute type B aortic dissection. The primary endpoint is to treat the aortic rupture, stop the bleeding and stabilize the hemodynamic status, with the aim to prevent mortality and major cardiac, cerebral, visceral and renal complications. Thoracic endovascular repair (TEVAR) is the most frequent management, although its planning, in these emergent patients, may be very difficult and sub-optimal imaging may result at post-operative examination (CT and MRI). In case of TEVAR is not the definitive treatment of the aortic disease, a second stage surgical management can be performed in elective status, in a patient with a total clinical recover. In acute and dramatic circumstances, like ruptured type B dissection, TEVAR is a valid and suitable bridge procedure to open surgery, reducing the overall risk for mortality and major complications.

Endovascular repair of acute uncomplicated aortic type B dissection promotes aortic remodelling: 1 year results of the ADSORB trial.

OBJECTIVES: Uncomplicated acute type B aortic dissection (AD) treated conservatively has a 10% 30-day mortality and up to 25% need intervention within 4 years. In complicated AD, stent grafts have been encouraging. The aim of the present prospective randomised trial was to compare best medical treatment (BMT) with BMT and Gore TAG stent graft in patients with uncomplicated AD. The primary endpoint was a combination of incomplete/no false lumen thrombosis, aortic dilatation, or aortic rupture at 1 year. METHODS: The AD history had to be less than 14 days, and exclusion criteria were rupture, impending rupture, malperfusion. Of the 61 patients randomised, 80% were DeBakey type IIIB. RESULTS: Thirty-one patients were randomised to the BMT group and 30 to the BMT+TAG group. Mean age was 63 years for both groups. The left subclavian artery was completely covered in 47% and in part in 17% of the cases. During the first 30 days, no deaths occurred in either group, but there were three crossovers from the BMT to the BMT+TAG group, all due to progression of disease within 1 week. There were two withdrawals from the BMT+TAG group. At the 1-year follow up there had been another two failures in the BMT group: one malperfusion and one aneurysm formation (p = .056 for all). One death occurred in the BMT+TAG group. For the overall endpoint BMT+TAG was significantly different from BMT only (p < .001). Incomplete false lumen thrombosis, was found in 13 (43%) of the TAG+BMT group and 30 (97%) of the BMT group (p < .001). The false lumen reduced in size in the BMT+TAG group (p < .001) whereas in the BMT group it increased. The true lumen increased in the BMT+TAG (p < .001) whereas in the BMT group it remained unchanged. The overall transverse diameter was the same at the beginning and after 1 year in the BMT group (42.1 mm), but in the BMT+TAG it decreased (38.8 mm; p = .062). CONCLUSIONS: Uncomplicated AD can be safely treated with the Gore TAG device. Remodelling with thrombosis of the false lumen and reduction of its diameter is induced by the stent graft, but long term results are needed.

Emergency Thoracic Endovascular Aneurysm Repair in Acute Type B Dissection with Visceral Malperfusion.

A 46-year-old female patient was admitted to the emergency room with the sudden onset of abdominal pain, back pain, and paresthesia in the right leg. An emergent chest computed tomography (CT) showed an acute Type B aortic dissection. An emergency thoracic endovascular aneurysm repair (TEVAR) procedure was subsequently performed, for an evolving visceral malperfusion syndrome. We performed the procedure using an axillary approach because the small diameter of the true lumen precluded transfemoral endovascular access. This case illustrates that TEVAR permits the treatment of complicated acute Type B aortic dissection; specifically, technical variations can expand the applicability of endovascular procedures.