Hybrid aortic arch repair for dissecting aneurysm

A systematic review and meta-analysis of retrograde type A aortic dissection after thoracic endovascular aortic repair in patients with type B aortic dissection

BACKGROUND

Retrograde type A dissection (RTAD) is a devastating complication of thoracic endovascular repair (TEVAR) with low incidence but high mortality. The objective of this study is to report the incidence, mortality, potential risk factors, clinical manifestation and diagnostic modalities, and medical and surgical treatments.

METHODS

A systematic review and single-arm and two-arm meta-analyses evaluated all published reports of RTAD post-TEVAR through January 2021. All study types were included, except study protocols and animal studies, without time restrictions. Outcomes of interest were procedural data (implanted stent-grafts type, and proximal stent-graft oversizing), the incidence of RTAD, associated mortality rate, clinical manifestations, diagnostic workouts and therapeutic management.

RESULTS

RTAD occurred in 285 out of 10,600 patients: an estimated RTAD incidence of 2.3% (95% CI: 1.9-2.8); incidence of early RTAD was approximately 1.8 times higher than late. Wilcoxon signed-rank testing showed that the proportion of RTAD patients with acute type B aortic dissection (TBAD) was significantly higher than those with chronic TBAD (P = .008). Pooled meta-analysis showed that the incidence of RTAD with proximal bare stent TEVAR was 2.1-fold higher than with non-bare stents: risk ratio was 1.55 (95% CI: 0.87-2.75; P = .13). Single arm meta-analysis estimated a mortality rate of 42.2% (95% CI: 32.5-51.8), with an I2 heterogeneity of 70.11% (P < .001).

CONCLUSION

RTAD is rare after TEVAR but with high mortality, especially in the first month post-TEVAR with acute TBAD patients at greater risk as well as those treated with proximal bare stent endografts.

A systematic review and meta-analysis of thoracic endovascular aortic repair with the proximal landing zone 0

Background

Thoracic endovascular aortic repair, initially intended for thoracic aortic disease treatment, has extended its application to the proximal zone of the aorta. However, the safety and surgical outcomes of extending the proximal landing zone into the ascending aorta (zone 0) in selected cases remain unknown. Thus, we performed a systematic review and meta-analysis of zone 0 thoracic endovascular aortic repair (TEVAR) to obtain a deeper understanding of its safety, outcomes, and trends over time.

Methods

A literature search was performed using PubMed, EMBASE, and Web of Science databases in accordance with the preferred reporting items for systematic reviews and meta-analyses guidelines, from January, 1997 to January, 2022. Only studies involving zone 0 TEVAR were included. The retrieved data from the eligible studies included basic study characteristics, 30-day/in-hospital mortality rate, indications, comorbidities, stent grafts, techniques, and complications. Summary effect measures of the primary outcomes were obtained by logarithmically pooling the data with an inverse variance-weighted fixed-effects model.

Results

Fifty-three studies with 1,013 patients were eligible for analysis. The pooled 30-day/in-hospital mortality rate of zone 0 TEVAR was 7.49%. The rates of post-operative stroke, type Ia endoleak, retrograde type A aortic dissection, and spinal cord ischemia were 8.95, 9.01, 5.72, and 4.12%, respectively.

Conclusions

Although many novel stent grafts and techniques targeting zone 0 TEVAR are being investigated, a consensus on technique and device selection in zone 0 TEVAR is yet to be established in current practice. Furthermore, the post-operative stroke rate is relatively high, while other complication rates and perioperative death rate are comparable to those of TEVAR for other aortic zones.

ALDH2 knockout protects against aortic dissection

Background

The incidence and mortality of aortic dissection (AD) are increasing. In pathological studies, macrophages, T lymphocytes and dendritic cells were found in the tunica media of the aorta. Acetaldehyde dehydrogenase 2 (ALDH₂) gene polymorphisms are associated with a high incidence of hypertension in Asian populations. However, there is no clear evidence of the relationship between ALDH₂ and aortic dissection in Asians. The aim of this study was to investigate the incidence of aortic dissection in different ALDH₂ genotypes and explore changes in the vasculature.

Materials and methods

Three-week-old male mice were administered freshly prepared β-aminopropionitrile solution dissolved in drinking water (1 g/kg/d) for 28 days to induce TAD. An animal ultrasound imaging system was used to observe the formation of arterial dissection and changes in cardiac function. Subsequently, mice were euthanized by cervical dislocation. The aortas were fixed for HE staining and EVG staining to observe aortic elastic fiber tears and pseudoluma formation under a microscope.

Results

Knockout of ALDH₂ mitigated β-aminopropionitrile-induced TAD formation in animal studies. Ultrasound results showed that ALDH₂ knockout reduced the degree of ascending aortic widening and the incidence of aortic dissection rupture. Pathological sections of multiple aortic segments showed that the protective effect of ALDH₂ knockout was observed in not only the ascending aorta but also the aortic arch and descending aorta. The expression levels of genes related to NK CD56bright cells, Th17 cells, T cells and T helper cells were decreased in ALDH₂ knockout mice treated with β-aminopropionitrile for 28 days.

Conclusion

ALDH₂ knockout protects against aortic dissection by altering the inflammatory response and immune response and protecting elastic fibers.

Early and Midterm Outcomes of Type II Hybrid Arch Repair for Complex Aortic Arch Pathology

Background

The hybrid arch repair (HAR) is an appealing surgical option in the management of aortic arch diseases. The aim is to evaluate the short and mid-term outcomes of type II HAR involving replacement of the ascending aorta, arch debranching, and zone 0 stent graft deployment in diverse arch pathologies.

Methods

200 patients with various diffuse aortic pathologies involving the arch were enrolled between 2016 and 2019. Complex arch diseases included acute type A dissection (n = 129, 64.5%), acute type B dissection (n = 16, 8.0%), aortic arch aneurysm (n = 42, 21.0%) and penetrating arch ulcer (n = 13, 6.5%). Mortality, morbidity, survival and re-intervention were analyzed.

Results

The overall 30-day mortality rate was 8.0% (16/200). Stroke was present in 3.5% (7/200) of the general cohort and spinal cord injury was occurred in 3.0% (6/200). Multivariable logistic analysis showed that cardiac malperfusion and CPB time were the risk factors associated with 30-day mortality. The mean follow-up duration was 25.9 months (range 1–57.2 months), and the 3-year survival rate was 83.1%. On Cox regression analysis, age, diabetes, cardiac malperfusion and CPB time predicted short and mid-term overall mortality. A total of 3 patients required reintervention during the follow-up due to the thrombosis of epiaortic artificial vessels (n = 1), anastomotic leak at the site of the proximal ascending aorta (n = 1) and the type I endoleak (n = 1).

Conclusions

Type II HAR was performed with satisfactory early and mid-term outcomes in complex aortic arch pathologies.

Midterm Outcomes of One-Stage Hybrid Aortic Arch Repair for Stanford Type A Aortic Dissection: A Single Center's Experience

This study sought to identify the midterm outcomes of one-stage hybrid aortic arch repair (HAAR) in patients with Stanford type A aortic dissection (TAAD). Between January 2010 and December 2015, 75 consecutive patients with TAAD involving the aortic arch who underwent one-stage type Ⅱ HAAR at our institution were identified. During this period, 496 consecutive patients with TAAD underwent traditional total aortic arch replacement (TAR) with frozen elephant trunk. The preoperative, perioperative and postoperative data of all patients were compared. A propensity score-matching analysis was applied to adjust for baseline risk factors. 571 patients were included for analysis (428 men; mean age, 48.9±11.1 years). For all patients, the mean follow-up time was 41.1±22.1 months, in-hospital mortality was 4.7% and the 5-year survival rate was 89.5%. Midterm outcomes between the propensity-matched groups were compared (59 HAAR vs TAR pairs). HAAR group showed shorter cardiopulmonary bypass time (105-159 min vs 158-230 min, p < 0.001), aortic cross-clamping time, postoperative ventilation time and intensive care unit stays (33-108 h vs 45-131 h, p = 0.010) than the TAR group. There were no significant differences in in-hospital mortality, rate of stroke and rate of paraplegia between the two groups, however, better 5-year survival rate was found in HAAR group (94.9% vs 75.8%, Log-rank p = 0.005). As compared to propensity matched cohort of TAR patients, HAAR shows good midterm outcomes for patients with TAAD. Further randomized study was needed to clarify the optimal management strategy of TAAD.

Fate of the Dissected Thoraco-Abdominal Aorta Distal to TEVAR (Thoracic Endovascular Aortic Repair) for Complicated Acute and Subacute Type B Aortic Dissection

PURPOSE

This study assessed morphological changes in the aortic true and false lumens during follow-up of patients undergoing TEVAR (Thoracic Endovascular Aortic Repair) for complicated acute and subacute type B dissection. The study analyzes the effectiveness of TEVAR in preventing distal aneurysmal progression.

MATERIALS AND METHODS

All patients between 2009 and 2019 undergoing TEVAR for complicated acute and subacute type B dissection at the study institution were retrospectively reviewed. Maximal diameters were measured on the proximal descending aorta right below the left subclavian artery, thoraco-abdominal junction right above the celiac trunk, and infrarenal aortic right above the inferior mesenteric artery, pre-operatively and during follow-up, analyzing either expansion or shrinkage of true and false lumens at these 3 sites.

RESULTS

Forty-one patients were included. Thirty-day incidence of death, stroke, paraplegia, and visceral ischemia was, respectively, 8% (n = 4), 6% (n = 3), 2% (n = 1), and 2% (n = 1). Three patients (6%) died from intervention-related cause. Mortality was 17% (n = 8) during a mean follow-up of 54 months. One patient had aneurysmal dilation of the descending aorta needing additional coverage and only 2 (4%) developed thoraco-abdominal aneurysms requiring re-intervention. In the remaining patients, both significant expansion of the true lumen and shrinkage of false lumen were observed at all 3 sites.

CONCLUSION

Proximal coverage of the main entry tear appears to prevent aneurysmal progression in most patients (96%). With such promising results, TEVAR should be considered as a first-line treatment in acute and subacute type B dissection.

Comparison of the Outcomes of Total Endovascular Aortic Arch Repair Between Branched Endograft and Chimney Endograft Technique in Zone 0 Landing

PURPOSE

Zone 0 landing in thoracic endovascular aortic repair (TEVAR) has recently gained increasing attention for the treatment of high-risk patients. The aim of this study was to compare the outcomes of total endovascular aortic arch repair between branched TEVAR (bTEVAR) and chimney TEVAR (cTEVAR) in the landing zone (LZ) 0.

MATERIALS AND METHODS

This was a single-center, retrospective, and observational cohort study. From January 2010 to March 2020, 40 patients (bTEVAR, n=25; cTEVAR, n=15; median age: 79 years) were enrolled in this study, with a median follow-up period of 4.1 years. These patients were considered unsuitable for open surgical treatment.

RESULTS

All procedures were successful and no cases of conversion to open repair were noted during the 30-day postoperative period. The 30-day mortality was 2.5% (n=1; bTEVAR [0 of 25, 0%] vs cTEVAR [1 of 15, 6.7%]; p=0.375), the perioperative stroke rate was 10.0% (n=4; bTEVAR [4 of 25, 16.0%] vs cTEVAR [0 of 15, 0%], p=0.278), and type 1a endoleak rate was 15.0% (n=6; bTEVAR [0 of 25, 0%] vs cTEVAR [6 of 15, 40.0%], p=0.001). The risk factor for stroke was atheroma grade of ≥2 in the brachiocephalic artery (p<0.001). The risk factor for type 1a endoleak was cTEVAR (p=0.001). The 8-year survival rate was 49.9%. The aorta-related death-free rate and aortic event-free rate at 8 years were 94.4% (bTEVAR: 95.5% vs cTEVAR: 93.3%, p=0.504) and 60.7% (bTEVAR: 70.7% vs cTEVAR: 40.0%, p=0.048), respectively.

CONCLUSIONS

Total endovascular aortic arch repair using bTEVAR and cTEVAR is feasible for the treatment of aortic arch diseases in high-risk patients who are unsuitable for open surgery. However, as the rate of stroke is high, strict preoperative evaluation to prevent stroke is needed. No rupture of the aneurysm was observed in cTEVAR, but patients should be selected carefully because of the high incidence of type 1a endoleak.

Comparison of Open Repair vs. the One-Stage Hybrid Extra-Anatomic Technique for Distal Aortic Arch Disease Treatment: Mid-term Outcomes With a Risk-Adjusted Analysis

Objective: This study aims to compare the short- and mid-term outcomes of the stented elephant trunk (SET) procedure combined with supra-arch branch reconstruction and one-stage hybrid arch repair combined thoracic endovascular aortic repair (TEVAR) with extra-anatomic bypass in the management of distal arch disease.

Methods: From January 2009 to January 2019, 97 patients underwent one-stage hybrid arch repair combined with TEVAR with extra-anatomic bypass (HAR group), and 206 patients underwent the SET procedure with supra-arch branch reconstruction (SET group). We used inverse-probability-of treatment weighting (IPTW) to adjust baseline differences.

Results: Before IPTW adjustment, there was no significant difference in operative mortality between the two groups (5.2 vs. 1.0%, P = 0.064). The incidences of stroke, spinal cord injury (SCI), acute kidney injury (AKI), and endoleak also showed no significant differences (4.1 vs. 0.5%, P = 0.066; 2.1 vs. 1.5%, P = 1.000; 0 vs. 1.0%, P = 0.831; 6.2 vs. 1.9%, P = 0.113, respectively). After IPTW adjustment, the incidences of stroke, SCI, and AKI showed no significant differences between the two groups (1.8 vs. 1.1%, P = 0.138; 0.8 vs. 1.6%, P = 0.448; and 0 vs. 0.7%, P = 0.148, respectively). However, the HAR group tended to have higher operative mortality and incidence of endoleak than the SET group (12.4 vs. 1.3%, P = 0.01; 9.9 vs. 1.8%, P = 0.031, respectively). In the multivariate analysis, open repair decreased the risks of endoleak (odds ratio [OR], 0.171, 95% CI, 0.060–0.401; P < 0.001) and operative mortality (OR, 0.093, 95% CI, 0.027–0.238; P < 0.001). The overall survival and event-free survival of the HAR group were significantly lower than those of the SET group (P < 0.001).

Conclusion: One-stage hybrid arch repair combined TEVAR with extra-anatomic bypass and the SET procedure with supra-arch branch reconstruction both provided good postoperative treatment outcomes for distal arch disease. However, hybrid arch repair increased the risks of endoleak and operative mortality. The SET procedure provided better mid-term survival than hybrid arch repair without increasing operative mortality. Carefully selecting the indications for the procedure, while receiving close long-term follow-up, may improve the survival rate of patients undergoing hybrid arch repair.

Hybrid repair of aortic arch with zone zero endografting-Case series with review of the literature

INTRODUCTION

We present single-institution results of types I and II hybrid procedures for aortic arch disease with 30-day and long-term results and review of the literature.

MATERIALS AND METHODS

This is a retrospective study of all patients that underwent zone 0 endografting and open bypass from ascending aorta to the arch vessels at our institution between January 2013 and 2020. The following data for the systematic review were extracted from eligible studies: 30-day/in-hospital mortality, stroke rate, spinal cord ischemia (SCI) rate, renal failure requiring dialysis, development of retrograde dissection, early (<30 days) types I and III endoleak, follow-up length, late (>30 days) endoleak, and late (>30 days) mortality.

RESULTS

Twelve patients underwent hybrid aortic arch treatment in our institution. The most common aortic arch pathology was degenerative aortic aneurysm. The rate of retrograde dissection and SCI was 8.33%. Regarding the literature data, a total of 768 patients undergoing types I and II hybrid aortic arch debranching procedure. The pooled rate of 30-day/in-hospital mortality was 10.96% (95% confidence interval [CI], 8.21-14.06), SCI pooled rate was 2.91% (95% CI, 1.76%-4.33%), and retrograde dissection pooled rate was 3.22% (95% CI, 1.99-4.72).

CONCLUSION

Hybrid arch techniques provide safe alternative to open repair with acceptable short- and midterm results.

[Endovascular and hybrid treatment of thoracic and thoracoabdominal aortic aneurysms and dissections]

The article deals with immediate and medium-term results of hybrid and endovascular treatment of 74 patients with various pathologies of the thoracic and thoracoabdominal aorta (31 with aneurysms, 43 with thoracic and thoracoabdominal aortic dissections). Elective and emergency interventions were performed in 49 and 25 patients, respectively. Endoprosthetic repair of the arch, descending thoracic and thoracoabdominal aorta was performed in 25 patients, hybrid operations in 47 subjects (open switch of brachiocephalic, visceral and renal arteries followed by aortic endoprosthetic repair - 37, endovascular methods of making a landing zone - 12). The duration of the follow-up period after discharge from hospital amounted to 24.9±16.3 months. The technical success level was 98.6%. The overall hospital mortality rate was 11% (n=8), elective - 4% (n=2), emergency - 24% (n=6). Eight patients underwent repeat interventions on the thoracic and thoracoabdominal aorta. The 5-year cumulative survival rate was 82.3%, with freedom from repeat interventions amounting to 51.3%. Hybrid operations on the arch and descending thoracic aorta are considered to be a relatively safe and effective method of treatment. Follow-up and timely treatment of remote complications after hybrid or endovascular operations are obligatory for improving the results.

Endovascular Treatment of Post Type A Chronic Aortic Arch Dissection With a Branched Endograft: Early Results From a Retrospective International Multicenter Study

OBJECTIVE

The objective of this study was to evaluate the outcome of endovascular aortic arch repair for chronic dissection with a custom-made branched endograft.

BACKGROUND

Acute type A aortic dissections are often treated with prosthetic replacement of the ascending aorta. During follow-up, repair of an aneurysmal evolution of the false lumen distal to the ascending prosthesis can be a challenge both for the surgeon and the patient.

METHODS

We conducted a multicenter, retrospective study of consecutive patients from 14 vascular units treated with a custom-made, inner-branched device (Cook Medical, Bloomington, IN) for chronic aortic arch dissection. Rates of in-hospital mortality and stroke, technical success, early and late complications, reinterventions, and mortality during follow-up were evaluated.

RESULTS

Seventy consecutive patients were treated between 2011 and 2018. All patients were considered unfit for conventional surgery. In-hospital combined mortality and stroke rate was 4% (n = 3), including 1 minor stroke, 1 major stroke causing death, and 1 death following multiorgan failure. Technical success rate was 94.3%. Twelve (17.1%) patients required early reinterventions: 8 for vascular access complication, 2 for endoleak correction, and 2 for pericardial effusion drainage. Median follow-up was 301 (138-642) days. During follow-up, 20 (29%) patients underwent secondary interventions: 9 endoleak corrections, 1 open repair for prosthetic kink, and 10 distal extensions of the graft to the thoracic or thoracoabdominal aorta. Eight patients (11%) died during follow-up because of nonaortic-related cause in 7 cases.

CONCLUSIONS

Endovascular treatment of aortic arch chronic dissections with a branched endograft is associated with low mortality and stroke rates but has a high reintervention rate. Further follow-up is required to confirm the benefits of this novel approach.

One-stage hybrid procedure for distal aortic arch disease: mid-term experience at a single center

Background

This study analyzes the outcomes of a one-stage hybrid procedure combining thoracic endovascular aortic repair (TEVAR) with extra-anatomic bypass in patients with distal aortic arch disease.

Methods

This retrospective study collected 103 hybrid procedures combining TEVAR with extra-anatomic bypass (mean age, 62.2±9.3 years; 90 males) performed from January 2009 to January 2019 at Beijing Anzhen Hospital. We analyzed 30-day and mid-term outcomes including survival rate and the incidence of stroke, spinal cord injury (SCI), and endoleak.

Results

Five deaths (4.6%) occurred within 30 days, including type I endoleak in Zone 1 (n=1), hemorrhagic shock (n=1), stroke (n=2), and stent migration (n=1). Two patients developed SCI. The median follow-up time was 39.5 (interquartile range, 13.6-69.0) months. In all, 14 late deaths occurred; these were due to stroke (n=2), severe pneumonia (n=1), aortic rupture caused by type I endoleak (n=3), and sudden death (n=8). Six late endoleaks occurred including three type I and one type II in Zone 1 and two type I in Zone 2. In a competing risks analysis, the incidences of reintervention at 7 years, late death, and survival without reintervention were 8%, 22%, and 70%, respectively. In a Cox risk model, stroke (HR, 21.602; 95% CI: 2.798–166.796; P=0.003) was the only risk factor for 30-day mortality. Stroke (HR, 19.484; 95% CI: 5.245–72.380; P<0.001), SCI (HR, 15.548; 95% CI: 2.754–87.786; P=0.002), and endoleak (HR, 4.626; 95% CI: 1.068–20.040; P=0.041) were independent risk factors for long-term mortality.

Conclusions

The one-stage hybrid procedure provides acceptable mid-term results with good mid-term patency of extra-anatomic bypass. Strict selection of patients suitable for hybrid repair can effectively improve the survival rate and reduce the incidence of complications. At the same time, close follow-up patients should receive close long-term follow-up after hybrid procedure.

Zone 1 Aortic Arch Hybrid Endovascular Repair with Extra-anatomical Bypass: A Meta-analysis

BACKGROUND

The aim of this meta-analysis is to determine the morbidity and mortality outcomes of adult patients with aortic arch disease managed with extra-anatomical bypass avoiding median sternotomy and cardiopulmonary bypass, with simultaneous or staged hybrid zone 1 endovascular aortic repair.

METHODS

Systematic literature searches of the MEDLINE, EMBASE, and Cochrane databases were carried out to identify relevant studies on zone 1 hybrid arch repair. Extracted data were analyzed by random effects models. Primary outcomes included 30-day or in-hospital mortality. Longitudinal survival was analyzed up to 7 years from date of operation. Secondary outcomes included in-hospital morbidity, as well as late endoleak and reintervention.

RESULTS

Twenty studies incorporating 348 patients were included. In-hospital or 30-day mortality was 10.1% (95% confidence interval, 6.7-14.9%). Overall operative technical success was 89.8% (83.7-93.8%). Early type 1 endoleak rate was 14.0% (7.4-24.7%). Stroke prevalence was 9.5% (6.1-14.3%). Spinal cord paraplegia prevalence was 3.8% (1.9-7.6%). Retrograde aortic dissection prevalence was 4.1% (1.5-10.6%). Survival at 1 year postoperatively was 77.2% (66.1-85.4%). Survival at 3 years postoperatively was 73.7% (59.2-84.4%). Survival beyond 4 years postoperatively (range 58-80 months) was 65.9% (53.6-76.4%). Late type 1 endoleak prevalence was 11.8% (5.5-23.7%). Overall rate of reintervention was 11.6% (6.4-20.1%).

CONCLUSIONS

Zone 1 hybrid repair has evidence for satisfactory short- and long-term morbidity/mortality outcomes and may be considered as an alternative approach to aortic arch disease.

Early and midterm results of thoracic endovascular aortic repair using a branched endograft for aortic arch pathologies: A retrospective single-center study

Background

Zone 0 landing hybrid thoracic endovascular aortic repair (TEVAR) includes a few moderately invasive surgical procedures. To reduce invasiveness, TEVAR with a branched aortic arch stent-graft can be considered. This study aimed to elucidate the effectiveness of performing TEVAR using a Bolton (Bolton Medical, Inc, Sunrise, Fla) branched endograft by analyzing early and midterm results.

Methods

We enrolled 28 patients (mean age, 78.4 years) who underwent TEVAR with the Bolton branched endograft in Osaka University Hospital between October 2012 and June 2018 with a mean follow-up period of 4.0 years. Double-side and single-side branched devices were used in 24 (85.7%) and 4 (14.3%) patients, respectively.

Results

All procedures were successful; no cases of endoleak or conversion to open repair were noted during the 30-day postoperative period. The perioperative stroke rate was 14.3% (4 out of 28); midterm stroke was not detected. All patients with perioperative stroke had atheroma grade ≥2 in the brachiocephalic artery. No type 1a endoleak was reported during the early or midterm results. The cumulative survival rate, aorta-related death-free rate, and aortic event-free survival rate at 5 years were 80.8%, 95.8%, and 81.6%, respectively.

Conclusions

We achieved satisfactory early and midterm results by using a Bolton branched endograft for high-risk patients with arch pathologies except for high postoperative stroke. Although this treatment method is associated with postoperative stroke, performing strict evaluation of atheroma may prevent such complication. By preventing intraoperative stroke, TEVAR with this custom-made Bolton branched endograft may be considered a less-invasive treatment.

Homemade Fenestrated Stent-Grafts for Complete Endovascular Repair of Aortic Arch Dissections

Purpose: To evaluate outcomes of homemade fenestrated stent-grafts for complete endovascular aortic repair of aortic arch dissections. Materials and Methods: From July 2014 through September 2018, 35 patients (mean age 66±11 years; 25 men) underwent homemade fenestrated stent-graft repair of acute (n=16) or chronic (n=10) complicated type B aortic dissections (n=16) and dissecting aortic arch aneurysms subsequent to surgical treatment of acute type A dissections (n=9). Nineteen (54%) procedures were emergent. Results: Zone 2 single-fenestrated stent-grafts were used in 25 cases; the remaining 10 were double-fenestrated stent-grafts deployed in zone 0. Median time for stent-graft modification was 18 minutes (range 16–20). Technical success was achieved in all cases. An immediate distal type I endoleak was treated intraoperatively. Among the double-fenestrated stent-graft cases, the left subclavian artery fenestration could not be cannulated in 2 patients and revascularization was required. Partial coverage of the left common carotid artery necessitated placement of a covered stent in 3 cases. One (3%) patient had a stroke without permanent sequelae. Two type II endoleaks required additional covered stent placement at 5 and 7 days postoperatively, respectively. The 30-day mortality was 6% (2 patients with ruptured aortic arch aneurysm). During a mean follow-up of 17.6±13 months, there was no aortic rupture or retrograde dissection. One late type I endoleak was treated with additional proximal fenestrated stent-graft placement. One type II endoleak is currently under observation. One additional patient died (unrelated to the aorta); overall mortality was 9%. All supra-aortic trunks were patent. Conclusion: The use of homemade fenestrated stent-grafts for endovascular repair of aortic arch dissections is feasible and effective for total endovascular aortic arch repair. Durability concerns will need to be assessed in additional studies with long-term follow-up.

Frozen elephant trunk and arch endografts for chronic thoracoabdominal aortic dissections

Chronic aortic dissecting aneurysms (TAAD) presenting after acute Stanford type A or B dissection includes both arch and/or thoracoabdominal aortic aneurysms (TAAA). Approximately 60% of patients who survive surgical treatment of acute type A aortic dissections will require another aortic procedure. Similarly, more than 70% of patients with chronic type B aortic dissections will experience false lumen dilation at 5-year follow-up, often requiring intervention. Open or hybrid aortic repairs of complex TAAD involving the arch and the TAAA are very demanding procedures for both patients and clinicians. Open surgery remains the first line therapy in fit patients. Recent development of branched arch devices has offered an alternative option for high-risk patients. Technical challenges associated with the endovascular management of these complex aneurysms include proximal sealing zone often located in the aortic arch or the ascending aorta, narrow true lumen working space, and aortic branch perfusion by either the true or false lumen, or both. Recent studies have reported encouraging results with endovascular treatment of these complex dissecting aneurysms, especially following open ascending aortic repair. The aim of this review was to describe the available strategies for arch repair in the setting of a chronic TAAD and to determine the subset of patients that can benefit from of a totally endovascular approach.

Zone zero hybrid arch exclusion versus open total arch replacement

Open total aortic arch replacement is one of the most technically demanding operations in cardiothoracic surgery, requiring operator expertise and intraoperative and postoperative teamwork. Despite current advancements in the field of open aortic surgery with regard to intraoperative brain protection and postoperative care, the morbidity and mortality associated with open total arch operations varies. Endovascular and hybrid procedures involving the use of zone 0 as a landing zone allow fair comparison between open total arch and hybrid operations. Hybrid procedures involving all of the other landing zones [1-4] should not be compared with open total arch replacement, as the extent of the pathology is different.

Objective analysis of midterm outcomes of conventional and hybrid aortic arch repair by propensity-score matching

OBJECTIVE

The aim of this study is to evaluate the objective outcomes of conventional total aortic arch repair (CTAR) and hybrid arch repair by using propensity-score matching to reduce selection bias.

METHODS

Between January 2006 and April 2016, 470 consecutive patients underwent isolated aortic arch repair (excluding hemiarch or partial arch reconstruction, and cases with concomitant cardiac surgeries) at a single cardiovascular institute. We categorized 337 total aortic arch repair with antegrade cerebral perfusion under circulatory arrest as the CTAR group and 58 hybrid aortic arch repair (HAR) with thoracic endovascular aortic repair as the HAR group. Seventy-five patients with scheduled and staged thoracic endovascular aortic repair after total aortic arch repair with elephant trunk were excluded. Then, we compared early and midterm outcomes between the propensity-matched group (43 CTAR vs HAR pairs).

RESULTS

There were no significant differences in 30-day and operative deaths between the CTAR and HAR groups (4.7% [2/43] vs 7.0% [3/43]; P = .4142 and 11.6% [5/43] vs 16.3% [7/43]; P = .5637). Although there were no significant differences in the incidences of other major complications, permanent stroke was observed more frequently in the HAR group (0% [0/43] vs 11.6% [5/43]; P = .0064) compared with the CTAR group. Matching analysis, however, revealed an equivalent 5-year survival rate between the CTAR and HAR groups (80.5% vs 59.9%; P = .1300).

CONCLUSIONS

Matching analysis revealed a significantly greater incidence of stroke in the HAR group but equivalent midterm outcomes in the hybrid group compared with the CTAR group.

Computational Fluid Dynamics and Aortic Thrombus Formation Following Thoracic Endovascular Aortic Repair

BACKGROUND

We present the possible utility of computational fluid dynamics in the assessment of thrombus formation and virtual surgical planning illustrated in a patient with aortic thrombus in a kinked ascending aortic graft following thoracic endovascular aortic repair.

METHODS

A patient-specific three-dimensional model was built from computed tomography. Additionally, we modeled 3 virtual aortic interventions to assess their effect on thrombosis potential: (1) open surgical repair, (2) conformable endografting, and (3) single-branched endografting. Flow waveforms were extracted from echocardiography and used for the simulations. We used the computational index termed platelet activation potential (PLAP) representing accumulated shear rates of fluid particles within a fluid domain to assess thrombosis potential.

RESULTS

The baseline model revealed high PLAP in the entire arch (119.8 ± 42.5), with significantly larger PLAP at the thrombus location (125.4 ± 41.2, p < 0.001). Surgical repair showed a 37% PLAP reduction at the thrombus location (78.6 ± 25.3, p < 0.001) and a 24% reduction in the arch (91.6 ± 28.9, p < 0.001). Single-branched endografting reduced PLAP in the thrombus region by 20% (99.7 ± 24.6, p < 0.001) and by 14% in the arch (103.8 ± 26.1, p < 0.001), whereas a more conformable endograft did not have a profound effect, resulting in a modest 4% PLAP increase (130.6 ± 43.7, p < 0.001) in the thrombus region relative to the baseline case.

CONCLUSIONS

Regions of high PLAP were associated with aortic thrombus. Aortic repair resolved pathologic flow patterns, reducing PLAP. Branched endografting also relieved complex flow patterns reducing PLAP. Computational fluid dynamics may assist in the prediction of aortic thrombus formation in hemodynamically complex cases and help guide repair strategies.

Insights from complex aortic surgery with a Streamliner device for aortic arch repair (STAR)

OBJECTIVE

Aortic arch aneurysms and thoracoabdominal aortic arch aneurysms are technically challenging to manage by established surgical and endovascular methods. The Streamliner Multilayer Flow Modulator device (Cardiatis, Isnes, Brussels, Belgium) offers an unorthodox option for these high-risk cases. The Streamliner device for aortic arch repair (STAR) study investigated complex aneurysm cases managed by the Streamliner Multilayer Flow Modulator device and offers an analytic solution for a clinical dilemma.

METHODS

Six cases were included, with a 1-year follow-up, comprising 4 pure arch aneurysms and 2 thoracoabdominal aortic arch aneurysms Crawford type I, from a multicenter database hosted by the Streamliner Multilayer Flow Modulator Global Registry. A total of 50% of cases were performed under instructions for use. All were American Society of Anesthesiology IV and originated from zone 0. All cases were computationally analyzed, which consisted of (1) simulating the treatment on the basis of the postoperative data, (2) repositioning the stents for the failed technical cases, and (3) assessing the effects of overlapping devices on branch patency.

RESULTS

Correct device placement induced aneurysm flow streamlining, which reduced the dynamic pressure by 23% to 66%, whereas incorrect placements promoted Failure Mode I with 58% and 16% dynamic pressure increases and aneurysm volume expansion up to 23%. Overlapped devices improved distal perfusion by increasing arch branch outflows from 5% to 24%. The Streamliner Multilayer Flow Modulator device does not benefit a sac volume greater than 400 cm³.

CONCLUSIONS

The Streamliner Multilayer Flow Modulator device is a new technology that can manage complex aortic arch aneurysms and thoracoabdominal aortic arch aneurysms with favorable clinical outcomes if it is performed under instructions for use. Careful procedure planning and perioperative virtual stent placement will avoid foreshortening, prevent inadequate stent overlap lengths, and provide insight into the sufficient numbers of required implanted devices.