Chronic Type B Aortic Dissection Research Articles

Therapeutic window for obtaining favorable remodeling after thoracic endovascular aortic repair of type B aortic dissection

ObjectiveThe purpose of the present study was to determine the most appropriate timing for thoracic endovascular aortic repair (TEVAR) of type B aortic dissection (TBAD) in terms of remodeling of the aorta. MethodsA total of 41 patients who had undergone TEVAR for the treatment of aortic dissection were included in the present study. The patients were divided into two groups: those who had undergone TEVAR in the acute or subacute phase (group A) and those who had undergone TEVAR in the chronic phase (group B). The indications for TEVAR as the treatment of TBAD were the presence of aortic rupture or malperfusion of the aortic branches, a maximum aortic diameter of ≥40 mm on the initial diagnostic computed tomography scan, and/or expansion of the aorta of ≥5 mm within 3 months for acute and subacute TBAD. The indication was a maximum aortic diameter of ≥50 mm or expansion of the aorta of ≥5 mm within 1 year for chronic TBAD. The diameters of the aorta, true lumen, and false lumen were measured at the level of the most dilated part of the descending aorta (level M) and at the diaphragm (level D) on the computed tomography scan obtained before TEVAR and at the 2-year follow-up examination. ResultsThe median interval between TEVAR and the onset of TBAD was 0.2 month (interquartile range, 0.03-0.7 month) in group A (n = 21) and 32 months (interquartile range, 4.7-35.2 months) in group B (n = 20). Except for the aortic diameter at level D in group B, favorable remodeling was obtained at both levels in both groups. The diameter change ratio of the aorta at level D was significantly greater in group A than in group B (P = .02). Receiver operating characteristic curve analysis of the interval for a significant decrease in the aortic diameter at level D yielded 4.2 months as the optimal threshold for performing TEVAR (area under the curve, 0.859; 95% confidence interval, 0.7-1.0). ConclusionsTEVAR for TBAD will result in favorable outcomes, irrespective of the timing of the procedure. However, it might be more effective to perform TEVAR within 4.2 months of the onset of TBAD, provided that the TEVAR procedure can be performed safely.

Hybrid Repair With Endovascular Debranching of the Aberrant Right Subclavian Artery for Complicated Type B Aortic Dissection in Patients With Kommerell’s Diverticulum

Purpose: Aberrant right subclavian artery (ARSA) associated with Kommerell’s diverticulum (KD) is a common congenital arch anomaly. It can be complicated by type B aortic dissection (TBAD) or aneurysmal formation at its ostium. Recently, hybrid repair with thoracic endovascular aortic repair (TEVAR) has appeared to be more favorable. Due to the normal anatomic proximity of the ARSA to the left subclavian artery (LSA) orifice in KD, coverage of the bilateral subclavian arteries (SCAs) to obtain an adequate proximal landing zone (PLZ) is usually required, and double cervicotomy for SCA revascularization potentially increases the risk of complications. Technique: This technique was demonstrated on a 50-year-old man presenting with progressive aneurysmal formation of KD with ARSA after chronic TBAD. A 3-step technique, namely left cervical debranching with a left common carotid artery to LSA bypass graft, TEVAR, and an LSA-to-ARSA endovascular debranching with a self-expanding covered stent by a through-and-through wire from the right brachial artery to the bypass graft, was performed in a 1-stage repair to cover the primary tear of TBAD and preserve the bilateral SCAs. The postoperative course was uneventful. Conclusion: This technique can prevent complications from double cervicotomy and achieve an adequate PLZ with preservation of the bilateral SCAs for TEVAR.

Ten-Year Clinical Characteristics and Early Outcomes of Type B Aortic Dissection Patients With Thoracic Endovascular Aortic Repair.

This study examined the 10-year hospitalization characteristics, economic patterns and early clinical outcomes of type B aortic dissection (TBAD) patients that underwent thoracic endovascular aortic repair (TEVAR) in one high-volume hospital in China. We performed a population-based retrospective analysis based on electronic medical record system data provided by Zhongshan Hospital Fudan University from 2009 to 2018. We identified 1,367 cases of TBAD patients with TEVAR over the past decade. The total incidence of in-hospital complications was 7.6% (104 of 1,367), among which acute kidney injury (AKI) had the highest incidence (3.1%, 42 of 1,367). Aortic-related reintervention was performed in 7 patients (0.5%). The overall aortic-related in-hospital mortality rate was 2.7% (37 of 1,367) and had no significant time-varying trend (P = 0.2). Among these, 27% of in-hospital deaths were caused by retrograde type A dissection (RTAD). Chronic TBAD had a higher risk of in-hospital death versus acute TBAD, with a risk ratio of 2.69 (95% confidence interval [CI]: 1.19-6.09). Patients with hypertension (risk ratio 4.63, 95% CI: 1.38, 15.54) also had a higher in-hospital death risk. These 2 factors were also the predictive factors for the composite endpoint of in-hospital adverse events (risk ratio 2.17, 95% CI: 1.43, 3.29 and risk ratio 4.83, 95% CI: 1.90, 12.28, respectively), in addition to Marfan syndrome (risk ratio 4.05, 95% CI: 1.61, 10.19). The average length of hospitalization significantly declined during the past decade (annual percentage change -6.3%, 95% CI -8.2 to -4.3), and the stent-grafts (SGs) cost was the main expenditure of the total hospitalization costs. Our study showed a favorable early outcome of TEVAR over the past decade. Greater attention should be paid to certain risk factors in order to reduce the in-hospital adverse events. SG expenditure is still the primary economic burden on Chinese TBAD patients.

Thoracic Endovascular Aortic Repair Practice in 13 Countries: A Report From VASCUNET and the International Consortium of Vascular Registries.

To assess practice patterns and short-term outcome after thoracic endovascular aortic repair (TEVAR), based on an international vascular registry collaboration. TEVAR has become the primary surgical treatment modality for descending aortic pathologies, and has expanded to new patient cohorts, including the elderly. Data on thoracic aortic aneurysms (TAA), type B aortic dissections (TBAD), and traumatic aortic injuries (TAI) treated with TEVAR from 2012 to 2016 were retrieved from registries and centers in 13 countries. Nine-thousand five-hundred eighteen TEVAR for TAA ( n = 4436), TBAD ( n = 3976) and TAI ( n = 1106) were included. The distribution of TEVAR procedures per pathology varied, with TAA repair constituting from 40% of TEVARs in the US to 72% in the UK ( P < 0.001).Mean intact TAA (iTAA) diameter varied from 59 (US) to 69 mm (Nancy, France) ( P < 0.001), 25.3% of patients having a diameter of <60 mm. Perioperative mortality after iTAA repair was 4.9%; combined mortality, stroke, paraplegia, and renal replacement therapy outcome was 12.8%. 18.6% of iTAA patients were ≥80 years old. Mortality was higher in this group (7.2%) than in patients <80 (3.8%) ( P < 0.001). After rTAA repair, perioperative mortality was 26.8%.Mortality was 9.7% after acute (within 14 days from onset of dissection) and 3.0% after chronic TBAD repair ( P < 0.001). Mortality after TAI was 7.8%, and depended on injury severity (grade IV (free rupture) 20.9%). This registry collaboration provides a unique platform to evaluate cross-border patterns of use and outcomes of TEVAR. A common core dataset is proposed, to achieve harmonization of registry-based quality outcome measures for TEVAR.

Clinical and Morphologic Outcomes of Endovascular Repair for Subacute and Chronic Type B Aortic Dissection

The objective of the study was to assess long-term remodeling, survival, and reintervention outcomes after thoracic endovascular aortic repair (TEVAR) for subacute and chronic type B aortic dissection (TBAD). All patients who underwent TEVAR for subacute or chronic TBAD at a tertiary referral center between 1999 and 2015 were included in this cohort study. The primary outcome was aortic remodeling, and secondary outcomes included survival, rate of major complications, and reinterventions. Fifty patients were included, with mean age of 62.4years, 10 (20%) DeBakey type IIIA and 40 (80%) DeBakey type IIIB dissection; 45 standard TEVAR, 2 branched TEVAR, 3 TEVAR combined with fenestrated or branched EVAR. Indication for TEVAR was intact (n=40) or ruptured (n=1) postdissection aneurysm, hypoperfusion (n=4), treatment-refractory pain (n=2), or a combination (n=3). Mean clinical follow-up was 76months, and median radiological follow-up was 46months. Thirty-day survival was 96%, stroke 4%, renal failure 0%, paraplegia 0%. Three- and five-year survival was 92% (95% confidence interval (CI) [79; 97]) and 77% (95% CI [61; 87]), respectively. Of 19 late deaths, 6 were confirmed aorta related. Five-year freedom from reintervention was 69% (95% CI [53-80]). Distal stent graft extension due to aortic dilatation composed most reinterventions. Mean maximal aortic diameter was 58.7mm preoperatively and 51.9mm on last follow-up (P=0.003). On thoracic level, true lumen expanded (+10.0mm, 95% CI [6.4; 13.6]) (P<0.001) and false lumen decreased (-11.9mm, 95% CI [-15.2; -8.5]) (P<0.001) from baseline to the last computed tomography. In the abdominal aorta, true lumen diameter change was +3.1mm (95% CI [1.4; 4.8]) (P=0.001); false lumen diameter change was +1.0mm (95% CI [-1.8; 3.8]) (P=0.464). TEVAR for subacute and chronic TBAD results in favorable remodeling of the thoracic but not the abdominal aorta. Five-year survival is almost 80%, but late aortic deaths still occur. Aortic dilatation distal to the treated segment requiring reintervention is common, emphasizing the importance of follow-up.

TEVAR for Chronic Type B Dissection: Highlighting the Importance of Patient Selection, Adjunctive False Lumen Procedures, Speaking the Same Language, and Industry Collaboration

Although originally controversial, thoracic endovascular aortic repair (TEVAR) for the indication of chronic type B aortic dissection (CTBAD) with associated descending aneurysm has slowly gained acceptance over the past 15 years. Our group was one of the early proponents of this technique,1 and in that first publication of our results described the concept of persistent retrograde false lumen perfusion via downstream fenestrations, as well as the fact that this persistent false lumen flow may be missed in the absence of delayed contrast imaging.

Thirty-Day Readmissions After Thoracic Endovascular Aortic Repair for Type B Aortic Dissection

Management of type B aortic dissection (TBAD) with thoracic endovascular aortic repair (TEVAR) carries a significant resource burden for the admitting hospital, including costs related to 30-day readmissions. Our objective was to define the patient population for 30-day readmissions after TEVAR for aortic dissection and to identify risk factors, readmission reasons, and possible preventive measures to reduce this readmission rate. A retrospective review of a prospectively collected database of all TEVARs performed to treat TBAD at a quaternary-level institution was performed. Patients readmitted to any of the institution's nine acute care hospitals within 30 days were identified and analyzed to characterize the significant demographic, comorbid, operative, and medical factors associated with readmission. Between 2012 and 2019, 294 patients underwent TEVAR for treatment of acute (n = 95 [48.8%]), subacute (n = 37 [12.6%]), or chronic (n = 112 [38.2%]) TBAD. Of the 279 patients alive at discharge, 45 patients (16.1%) were readmitted within 30 days, with a mean time to readmission of 11.8 ± 8.9 days. Readmission primary diagnosis was most commonly aorta related (n = 13 [28.9%]) or heart related (n = 11 [24.4%]); other reasons included gastroenterologic (n = 6 [13.3%]), neurologic (n = 5 [11.1%]), pulmonary related (n = 4 [8.9%]), infectious (n = 3 [6.7%]), and nonclassified (n = 2 [4.4%]). Of 45 readmitted patients, 7 (15.5%) underwent a secondary intervention during the index readmission. Preoperative renal failure (creatinine concentration >1.5 mg/dL) was associated with an increased rate of 30-day readmission (31.1% vs 16.7%; P = .024), as was private insurance status (26.7% vs 13.7%; P = .029). Patients who underwent intentional left subclavian artery coverage (zone 2) or had visceral/renal stents implanted at the time of TEVAR trended toward higher 30-day readmission rates compared with patients undergoing descending thoracic aortic coverage (zone 3-5) only (46.7% vs 37.8% vs 15.6%; P = .088). Blood pressure range and heart rate range in the 24-hour period before discharge were not predictive of 30-day readmission. Pain status and creatinine level at discharge were also not associated with increased rate of 30-day readmission. A consequential number of patients require readmission within 30 days after surgical treatment of TBAD with TEVAR. Reasons for readmission are commonly aorta related and heart related and are associated with preoperative renal failure and insurance status. Increased case complexity, including coverage of the left subclavian artery or the need for visceral/renal stenting at the time of TEVAR, is an independent predictor of increased 30-day readmission rate. Effectiveness of medical impulse control was not associated with 30-day readmission. These data provide insight into the quality-oriented metrics associated with endovascular treatment of TBAD.

Long-Term Remodeling and Survival Outcomes of Thoracic Endovascular Repair for Chronic Type B Aortic Dissection

Introduction - Based on favorable survival outcome compared to open repair, thoracic endovascular aortic repair (TEVAR) has become the treatment of choice in the setting of acute complicated type B aortic dissection1. It is increasingly used in treatment of chronic type B aortic dissection (CBAD)2, but the scientific basis for this is scarce. Aortic remodeling after TEVAR has been associated with improved survival, while it has been suggested that lack of aortic remodeling may be associated with worse outcome3.

Surgical Outcomes And Postoperative Descending Aorta Morphologic Remodeling After Thoracic Endovascular Aortic Repair For Acute And Chronic Type B Aortic Dissection.

BackgroundThis study aims to investigate the descending aortic morphological alterations caused by pathological changes in acute and chronic Type B aortic dissection (TBAD) and morphological remodeling after thoracic endovascular aortic repair (TEVAR).Patients and methodsFrom February 2012 to January 2016, 86 TBAD patients undergoing TEVAR were divided into an acute group (n=63) and a chronic group (n=23). The areas of the true, false and maximal lumen and descending aorta morphological parameters, including the taper ratio (TR), oversizing ratio (OR), mismatch ratio (MR), radius of curvature (RoC) and tortuosity index (TI), were evaluated. Follow-ups were performed postoperatively before discharge, at 1 and 6 months, and yearly thereafter.ResultsBefore TEVAR, the TR (0.57 (0.49) vs 0.74 (0.60); P < 0.05), OR (2.75 ± 1.89 vs 3.96 ± 2.27; P < 0.05) and TI (1.22 (1.19) vs 1.41 ± 0.17; P < 0.05) were significantly higher in the chronic group than in the acute group. The TEVAR technical success rate was 100%. No differences were found in 30-day and >30-day mortality between the two groups. Pathology-specific devices, such as tapered stent grafts and distal bare stents, were used more frequently in the chronic group than in the acute group (47.8% vs 23.8%, P = 0.03; 43.5% vs 12.7%, P = 0.002, respectively). The OR and TI changes that occurred after TEVAR were significantly higher in the chronic group than in the acute group (1.80 ± 0.86 vs 2.98 ± 1.85, P = 0.028; 0.00 ± 0.09 vs 0.09 ± 0.10, P < 0.001, respectively).ConclusionTEVAR is a safe and effective therapy for acute and chronic TBAD. Compared to acute TBAD, chronic TBAD resulted in an adverse preoperative descending aorta morphology. Pathology-specific devices may be a feasible treatment option for endovascular repair of chronic TBAD. A larger series of cases with longer follow-up are needed to draw definitive conclusions.

3067 Biomechanical analysis of acute versus chronic aortic dissection flaps

OBJECTIVES/SPECIFIC AIMS: Thoracic endovascular aortic repair (TEVAR) is more effective in remodeling the dissected aorta in acute versus chronic type B aortic dissection (TBAD). It has been hypothesized that this is due to differences in dissection flap biomechanical and structural properties but has not been confirmed in explanted human aortic tissue. We aimed to characterize and compare differences in tissue biomechanics and microstructure between acute and chronic dissection flaps that may underlie these findings. METHODS/STUDY POPULATION: Dissection flaps were obtained at time of operative repair for patients presenting for open aortic replacement to treat acute type A (ACUTE, n=7) or chronic type B (CHRONIC, n=7) aortic dissection. Given that the current treatment modality for acute complicated TBAD is TEVAR, it was not feasible to acquire acute TBAD flaps for analysis. Tissues were cryopreserved and subjected to biaxial tensile testing in the circumferential and longitudinal directions. Stiffness was quantified by the tangent modulus (TM) in the low and high linear regions of the compiled equibiaxial response curves for each cohort. Extensibility was defined as the intersection of the fitted line from the high linear region with the x-axis, and the degree of anisotropy (DA) was defined as the mean absolute percentage error of the strains in both directions. Flap architecture and collagen fiber organization were also compared between groups using two-photon microscopy. RESULTS/ANTICIPATED RESULTS: Average age of dissection flaps were 3.4±3.4 days in ACUTE and 1,868.7±1,354.0 days in CHRONIC (p=0.011). There were no differences in age, co-morbidities, maximum aortic diameter, and aortic wall thickness. ACUTE exhibited an anisotropic stress-strain response with increased extensibility longitudinally than circumferentially (0.18 vs. 0.09, p=0.022, DA=0.67) while CHRONIC demonstrated an isotropic response with similar extensibility in either direction (0.11 vs. 0.12, p=0.606, DA=0.26). CHRONIC and ACUTE had comparable stiffness in the circumferential direction (TMlow 439.92 vs. 541.08, p=0.729, and TMhigh 1585.19 kPa vs. 1869.35 kPa, p=0.817). In the longitudinal direction, CHRONIC was significantly stiffer than ACUTE (TMhigh 8347.61 kPa vs. 1201.34 kPa, p=0.049) (FIGURE). Microscopy corroborated these findings with greater collagen fiber organization circumferentially than longitudinally in ACUTE and increasing fibrosis, collagen predominance, and straightening of collagen fibers in CHRONIC. DISCUSSION/SIGNIFICANCE OF IMPACT: Compared to ACUTE, CHRONIC exhibited loss of anisotropy with increased tissue stiffness in the longitudinal direction. Increased dissection flap fibrosis and decreased compliance may explain the worse outcomes for aortic remodeling after TEVAR in chronic TBAD. This study offers biomechanical support for early TEVAR in the acute phase of uncomplicated TBAD.

Implications of secondary aortic intervention after thoracic endovascular aortic repair for acute and chronic type B dissection

BackgroundThoracic endovascular aortic repair (TEVAR) has become a mainstay of therapy for acute and chronic type B aortic dissection (TBAD). Dynamic aortic morphologic changes, untreated dissected aorta, and persistent false lumen perfusion have significant consequences for reintervention after TEVAR for TBAD. However, few reports contrast differences in secondary aortic intervention (SAI) after TEVAR for TBAD or describe their influence on mortality. This analysis examined incidence, timing, and types of SAI after TEVAR for acute and chronic TBAD and determined their impact on survival. MethodsAll TEVAR procedures for acute and chronic TBAD (2005-2016) were retrospectively reviewed. Patients with staged (<30 days) or concomitant ascending aortic arch repair or replacement were excluded. Acuity was defined by symptom onset (0-30 days, acute; >30 days, chronic). SAI procedures were grouped into open (intended treatment zone or remote aortic site), major endovascular (TEVAR extension or endograft implanted at noncontiguous site), and minor endovascular (side branch or false lumen embolization) categories. Kaplan-Meier methodology was used to estimate freedom from SAI and survival. Cox proportional hazards were used to identify SAI predictors. ResultsTEVAR for TBAD was performed in 258 patients (acute, 49% [n = 128]; chronic, 51% [n = 130]). Mean follow-up was 17 ± 22 months with an overall SAI rate of 27% (n = 70; acute, 22% [28]; chronic, 32% [42]; odds ratio, 1.7; 95% confidence interval, 0.9-2.9; P = .07]. Median time to SAI was significantly less after acute than after chronic dissection (0.7 [0-12] vs 7 [0-91] months; P < .001); however, freedom from SAI was not different (1-year: acute, 67% ± 4%, vs chronic, 68% ± 5%; 3-year: acute, 65% ± 7%, vs chronic, 52% ± 8%; P = .7). Types of SAI were similar (acute vs chronic: open, 61% vs 55% [P = .6]; major endovascular, 36% vs 38% [P = .8]; minor endovascular, 21% vs 21% [P = 1]). The open conversion rate (either partial or total endograft explantation: acute, 10% [13/128]; chronic, 15% [20/130]; P = .2) and incidence of retrograde dissection (acute, 6% [7/128]; chronic, 4% [5/130]; P = .5) were similar. There was no difference in survival for SAI patients (5-year: acute + SAI, 55% ± 9%, vs acute without SAI, 67% ± 8% [P = .3]; 5-year: chronic + SAI, 72% ± 6%, vs chronic without SAI, 72% ± 7% [P = .7]). Factors associated with SAI included younger age, acute dissection with larger maximal aortic diameter at presentation, Marfan syndrome, and use of arch vessel adjunctive procedures with the index TEVAR. Indication for the index TEVAR (aneurysm, malperfusion, rupture, and pain or hypertension) or remote preoperative history of proximal arch procedure was not predictive of SAI. ConclusionsSAI after TEVAR for TBAD is common. Acute TBAD has a higher proportion of early SAI; however, chronic TBAD appears to have ongoing risk of remediation after the first postoperative year. SAI types are similar between groups, and the occurrence of aorta-related reintervention does not affect survival. Patients' features and anatomy predict need for SAI. These data should be taken into consideration for selection of patients, device design, and surveillance strategies after TEVAR for TBAD.

Outcomes of Chimney Technique for Preservation of the Left Subclavian Artery in Type B Aortic Dissection

To report outcomes of the chimney technique for preservation of the left subclavian artery (LSA) in patients with type B aortic dissection (TBAD). A retrospective analysis was performed of a prospectively maintained database from August 2012 to October 2017. Primary endpoints were 30 day and overall mortality. Secondary endpoints were technical success, type Ia endoleak, chimney stent occlusion, aortic rupture, stroke, spinal cord ischaemia, and re-intervention rate. A total of 159 patients (mean age 54 ± 11 years; 141 men) with TBAD were treated using the chimney technique for LSA revascularisation. Acute, subacute, and chronic TBAD accounted for 64%, 28%, and 8% of cases, respectively. One hundred and six cases (67%) were complicated TBAD. One hundred and fifty-six patients (98%) were treated electively, while three (2%) were treated urgently because of intestinal or lower extremity ischaemia. The 30 day mortality and morbidity rates were 2% (3/159) and 4% (7/159), respectively. The technical success rate was 81% (129/159) and immediate type Ia endoleak occurred in 30 (19%) patients. Three major strokes, two spinal cord ischaemia and one aortic rupture, occurred early on. During a mean follow up of 23 ± 16 months (range 1-65 months), three more patients died: from aortic rupture, cerebral haemorrhage, and rectal cancer, respectively. Chimney stent occlusions were observed in four patients and all these chimney stents were self expanding. During follow up, two major strokes, one late type Ia endoleak and one re-intervention, occurred. According to the Kaplan-Meier curve, the estimated one and three year survival rates were 98.1 ± 1.1% and 94.4 ± 2.4%, respectively. Short and mid-term outcomes in the present study demonstrate that the chimney technique is safe and feasible for preservation of the LSA in patients with TBAD, but the durability of chimney stent needs to be evaluated carefully and immediate type Ia endoleak is a concern.

Endovascular repair of type B aortic dissection with the restrictive bare stent technique: morphologic changes, technique details, and outcomes.

PurposeThe aim of this study was to present our experience and assess the morphologic changes of the descending aorta after the restrictive bare stent (RBS) technique in the treatment of type B aortic dissection (TBAD).Patients and methodsA retrospective study was conducted of 22 consecutive patients with TBAD who underwent RBS treatment between February 2012 and June 2016. Indications for the RBS procedure included radiological evidence of true lumen (TL) compression or collapse and/or tortuosity index (TI) of the descending aorta >1.4. Technique success, descending aorta morphology, and clinical outcomes were evaluated.ResultsThe technical success rate was 100%. Patients treated with the RBS technique were often accompanied by TL collapse (45.5%) or TI >1.4 (59.1%). One-month postoperative computed tomography angiography showed that the taper ratio, oversizing ratio of the stent graft, and TI values were significantly decreased compared with preoperative computed tomography angiography values (P<0.05). The 30-day mortality rate was 0%. In total 95.2% had a thrombosed false lumen in the segment of aortic coverage, and TL diameters were increased in 40.3%±11% (mean ± SD) and 37.5%±17.9% of patients in the thoracic and abdominal segments, respectively. During the follow-up from 16 to 64 months (33±19 months), no distal stent graft-induced new entry, endoleak, and paraplegia were observed. One patient died from rupture of a chronic TBAD with aneurysm degeneration.ConclusionMid-term outcomes showed RBS to be a flexible and feasible approach to repair TBAD. RBS corrects the descending aorta morphology and promotes TL expansion in most patients, but the rupture of chronic TBAD with aneurysm degeneration was not prevented in all patients.

Outcomes from the Gore Global Registry for Endovascular Aortic Treatment in patients undergoing thoracic endovascular aortic repair for type B dissection

ObjectiveThe Global Registry for Endovascular Aortic Treatment (GREAT) is a prospective multicenter registry collecting real-world data on the performance of W. L. Gore (Flagstaff, Ariz) aortic endografts. The purpose of the present study was to analyze the implementation and outcomes of thoracic endovascular aortic repair (TEVAR) in GREAT patients with type B aortic dissection (TBAD). MethodsFrom 2010 to 2016, >5000 patients were enrolled in the GREAT from 113 centers in 14 countries across 4 continents. The study population comprised those treated for TBAD. The primary outcomes of interest were mortality and freedom from aortic events (AEs). ResultsA total of 264 patients (80% male; mean age, 62 years) underwent TEVAR for the treatment of 170 (64%) acute and 94 (36%) chronic cases of TBAD. Chronic TBAD patients required significantly longer endograft coverage than did acute TBAD patients (P = .05). Early postoperative complications occurred in 9% of patients, with no difference in chronic vs acute dissection (P = .11). The 30-day aortic mortality and all-cause mortality were 1.5% and 2.3%, respectively, with no differences based on chronicity. During a mean follow-up of 26 months, the total aortic mortality was 2.7% and the total all-cause mortality was 12.5%. The all-cause mortality was significantly greater for chronic vs acute TBAD (19.2% vs 8.8%, respectively; P = .02). On multivariate analysis, patients with acute uncomplicated dissections had significantly improved overall survival compared with all other categories of dissections (93% vs 83% at 2 years; P < .05). A proximal landing zone diameter >40 mm was associated with an increased risk of retrograde type A dissection (18% vs 2%; P = .02). Patients undergoing left subclavian artery (LSA) coverage experienced a twofold greater rate of AEs compared with noncoverage patients (P < .01). Patients who underwent LSA revascularization experienced a 1.5-fold greater rate of AEs compared with patients covered without revascularization (P = .04). ConclusionsTEVAR for TBAD using the conformable GORE TAG thoracic endoprosthesis device can be performed with a low incidence of aortic mortality and complications. Acute uncomplicated TBAD patients had a significantly lower mortality rate than that of other patients. Larger proximal landing zones were associated with more frequent retrograde type A dissection. LSA involvement (coverage and/or revascularization) was associated with an increased risk of AEs during follow-up.

Images of the aorta 3 months prior to current admission, show chronic type-B aortic dissection with enlarged size of the proximal descending aorta

Images of the aorta 3 months prior to current admission, show chronic type-B aortic dissection with enlarged size of the proximal descending aorta

Endovascular Optimization of Distal Seal During Stent-Graft Repair of Chronic Type-B Aortic Dissection (TBAD)

Endovascular Optimization of Distal Seal During Stent-Graft Repair of Chronic Type-B Aortic Dissection (TBAD)

Computational Study of Anatomical Risk Factors in Idealized Models of Type B Aortic Dissection

Several risk factors have been identified in type B aortic dissection (TBAD), namely tear size, location, patency and number, and false lumen (FL) location. However, the individual impact of each of these factors is poorly understood. The impact of these factors was investigated using computational fluid dynamics (CFD). Fourteen idealized models of chronic TBAD were created of different shapes (straight vs. curved vessels), different number of proximal and distal tears, tear size (4, 10, and 20mm diameter) and shape (circular or elliptical), FL location (inner or outer arch), treated (stented), and untreated. All models had identical length, relative size of true lumen (TL) and FL, and inlet (flow) and outlet (pressure) boundary conditions. Using validated CFD tools, inlet mean pressure (MP), pulse pressure (PP), TL and FL pressures, velocities, and flows were computed for each model. AD increased PP and MP relative to undissected aorta. Curvature did not change pressure and flow ratio between TL and FL. Inner curvature FL showed slightly larger pressures and tear velocities. Larger tears decreased hemodynamic differences between TL and FL. The combination of proximal and distal tear size determines the overall hemodynamics: larger proximal tears increased FL PP by up to 76%. Conversely, larger distal tears decreased FL PP and MP. Large proximal and distal tears decreased tear velocity (by up to 65%) and increased FL flow (up to 12 times). Proximal tear stenting resulted in a 54% reduction of PP. Conversely, distal occlusion tear increased FL PP and MP by 144% and 7%, respectively. Unfavorable hemodynamic conditions such as larger FL pressure occur when distal tear is small or absent, proximal tears are large, and FL is at the inner curvature, in agreement with previous clinical studies. CFD analysis is a powerful tool to understand the interplay between anatomy and hemodynamics in TBAD.

Contemporary Management Strategies for Chronic Type B Aortic Dissections: A Systematic Review.

BackgroundCurrently, the optimal management strategy for chronic type B aortic dissections (CBAD) is unknown. Therefore, we systematically reviewed the literature to compare results of open surgical repair (OSR), standard thoracic endovascular aortic repair (TEVAR) or branched and fenestrated TEVAR (BEVAR/FEVAR) for CBAD.MethodsEMBASE and MEDLINE databases were searched for eligible studies between January 2000 and October 2015. Studies describing outcomes of OSR, TEVAR, B/FEVAR, or all, for CBAD patients initially treated with medical therapy, were included. Primary endpoints were early mortality, and one-year and five-year survival. Secondary endpoints included occurrence of complications. Furthermore, a Time until Treatment Equipoise (TUTE) graph was constructed.ResultsThirty-five articles were selected for systematic review. A total of 1081 OSR patients, 1397 TEVAR patients and 61 B/FEVAR patients were identified. Early mortality ranged from 5.6% to 21.0% for OSR, 0.0% to 13.7% for TEVAR, and 0.0% to 9.7% for B/FEVAR. For OSR, one-year and five-year survival ranged 72.0%-92.0% and 53.0%-86.7%, respectively. For TEVAR, one-year survival was 82.9%-100.0% and five-year survival 70.0%-88.9%. For B/FEVAR only one-year survival was available, ranging between 76.4% and 100.0%. Most common postoperative complications included stroke (OSR 0.0%-13.3%, TEVAR 0.0%-11.8%), spinal cord ischemia (OSR 0.0%-16.4%, TEVAR 0.0%-12.5%, B/FEVAR 0.0%-12.9%) and acute renal failure (OSR 0.0%-33.3%, TEVAR 0.0%-34.4%, B/FEVAR 0.0%-3.2%). Most common long-term complications after OSR included aneurysm formation (5.8%-20.0%) and new type A dissection (1.7–2.2%). Early complications after TEVAR included retrograde dissection (0.0%-7.1%), malperfusion (1.3%–9.4%), cardiac complications (0.0%–5.9%) and rupture (0.5%–5.0%). Most common long-term complications after TEVAR were rupture (0.5%–7.1%), endoleaks (0.0%–15.8%) and cardiac complications (5.9%-7.1%). No short-term aortic rupture or malperfusion was observed after B/FEVAR. Long-term complications included malperfusion (6.5%) and endoleaks (0.0%-66.7%). Reintervention rates after OSR, TEVAR and B/FEVAR were 5.8%-29.0%, 4.3%-47.4% and 0.0%-53.3%, respectively. TUTE for OSR was 2.7 years, for TEVAR 9.9 months and for B/FEVAR 10.3 months.ConclusionWe found a limited early survival benefit of standard TEVAR over OSR for CBAD. Complication rates after TEVAR are higher, but complications after OSR are usually more serious. Initial experiences with B/FEVAR show its feasibility, but long-term results are needed to compare it to OSR and standard TEVAR. We conclude that optimal treatment of CBAD remains debatable and merits a patient specific decision. TUTE seems a feasible and useful tool to better understand management outcomes of CBAD.

Postoperative glucocorticoid enhances recovery after endovascular aortic repair for chronic type B aortic dissection: a single-center experience.

BackgroundThoracic endovascular aortic repair (TEVAR) has been chosen as a less invasive alternative for type B aortic dissections (TBADs). However, the therapeutic effect of TEVAR has been challenged by postoperative adverse events, which were induced by inflammatory response. Glucocorticoids have been widely used because of the powerful and effective anti-inflammatory properties. Nevertheless, the prognostic effect of glucocorticoids after TBAD patients underwent TEVAR remains unclear. The objective of this study was to assess the potential effect of postoperative glucocorticoids on the prognosis of TEVAR for TBADs.MethodsA total of 92 chronic TBADs patients underwent TEVAR with epidural anesthesia between June 2012 and June 2014 was retrospectively reviewed. The patients were stratified into dexamethasone (DXM) and non-dexamethasone group (N-DXM). The indications for TEVAR were as following: malperfusion (n = 28); contained or impending rupture (n = 17); persistent intractable chest/back pain (n = 32); refractory hypertension (n = 15).ResultsNo 30-day mortality and incision infection occurred in each group. The postoperative pain score on the second day was significantly higher in N-DXM group (3.60 ± 0.21 versus 4.83 ± 0.32, P = 0.001). The differences of white blood cell, body temperature and heart rate were pronounced in both groups judged by the peak values (13.01 ± 0.58 × 109/L versus 10.04 ± 0.61 × 109/L, 37.67 ± 0.08 °C versus 37.92 ± 0.09 °C and 89.06 ± 1.21 bpm versus 95.95 ± 1.70 bpm, P = 0.002, 0.04 and 0.001, respectively). The white blood cells in DXM group significantly increased on the second and third postoperative day (P = 0.009 and 0.023), while the body temperature and heart rate showed an apparent decline on the second (P = 0.001 and 0.028), third (P = 0.007 and 0.005) and fourth postoperative days (P = 0.024 and 0.018). However, the changes of false lumen volumes and the endoleak incidence at 3-month follow-up were comparable in the two groups. No significant difference of post-implantation syndrome was observed either.ConclusionsAlthough postoperative prophylactic glucocorticoids administration was unable to influence mortality, incision infection or the change of false lumen volumes, it enabled to enhance the recovery of vital signs and alleviate the postoperative pain. A prospective, randomized controlled trial has been registered (NCT02523300), which will be warranted before prophylactic administration of glucocorticoids after TEVAR procedure could be recommended in the clinical work.Electronic supplementary materialThe online version of this article (doi:10.1186/s12872-016-0234-2) contains supplementary material, which is available to authorized users.

Operative Results and Clinical Features of Chronic Stanford Type B Aortic Dissection: Examination of 234 Patients Over 6 Years

Recently, the indications for thoracic endovascular aortic repair (TEVAR) have been expanding, and the applicability of TEVAR for acute type B aortic dissection (TBAD) is proposed with regard to the high mortality of open surgery for chronic TBAD. TEVAR in the acute phase may lead to remodeling of the false lumen (FL), but it is controversial whether it completely resolves the aortic expansion in the chronic phase. In this study, operative results and the relationship between FL status and the time before surgical intervention were retrospectively analyzed. From January 2008 to September 2013, 234 patients underwent open surgery for chronic TBAD. Most patients were on left heart bypass. By considering Japanese aortic disease treatment guidelines and the smaller physique of Japanese patients, operative indications were aneurysm >50mm in diameter or rapid aneurysm enlargement of >5mm in a 6 month period. In 180 cases, the FL was patent. The mean interval between onset of TBAD and operation was 61±54 months. There was no significant difference between patients in the patent FL group and those in the thrombosed FL group (p=.44). Mean ratio of FL diameter to maximum aortic diameter (FL/AD) was 0.64±0.21. There was no correlation between FL and AD before the operation (r=.12). Descending thoracic aortic replacement (DTAR) was performed in 127 cases and thoracic ascending aortic replacement (TAAR) in 107 cases (Crawford type I, n=9; Crawford type II, n=65; Crawford type III and IV, n=22, respectively; Safi type V, n=11). The overall operative mortality was 6.8%: 3.9% (5/127) for DTAR and 10.3% (11/107) for TAAR. The three year survival was 86.7, and the freedom from re-intervention rate was 97.0%. Enlargement of uncomplicated TBAD in the chronic phase was poorly related to FL status and the results of open repair have improved. However, further prospective study is necessary.