Evolving practice pattern changes and outcomes in the era of hybrid aortic arch repair

The outcomes of aortic arch repair between open surgical repair and debranching endovascular hybrid surgical repair: A systematic review and meta-analysis

BACKGROUND

At present, open surgical aortic arch repair (OAR) and debranching hybrid surgical aortic arch repair (HAR) serve as significant therapeutic approaches for aortic arch aneurysm or dissection. It remains unclear which technique is preferable. Our study aimed to compare the short-term and long-term outcomes of these two procedures.

METHODS

To identify comparison studies of debranching HAR and OAR, a systematic search of the PubMed, Embase, Web of Science, and Cochrane Library databases was performed from January 2002 to April 2022. This study was registered on PROSPERO (CRD42020218080).

RESULTS

Sixteen publications (1316 patients), including six propensity score-matching (PSM) analysis papers, were included in this study. Compared with the HAR group, the patients who underwent OAR were younger (OAR vs HAR: 67.53 ± 12.81 vs 71.29 ± 11.0; P < .00001), had less coronary artery disease (OAR vs HAR: 22.45% vs 32.6%; P = .007), less chronic obstructive pulmonary disease (OAR vs HAR: 16.16% vs 23.92%; P = .001), lower rates of previous stroke (OAR vs HAR: 12.46% vs 18.02%; P = .05), and a lower EuroSCORE (European System for Cardiac Operative Risk Evaluation) score (OAR vs HAR: 6.27 ± 1.04 vs 6.9 ± 3.76; P < .00001). HAR was associated with less postoperative blood transfusion (OAR vs HAR: 12.23% vs 7.91%; P = .04), shorter length of intensive care unit stays (OAR vs HAR: 5.92 ± 7.58 days vs 4.02 ± 6.60 days; P < .00001) and hospital stays (OAR vs HAR: 21.59 ± 17.54 days vs 16.49 ± 18.45 days; P < .0001), lower incidence of reoperation for bleeding complications (OAR vs HAR: 8.07% vs 3.96%; P = .01), fewer postoperative pulmonary complication (OAR vs HAR: 14.75% vs 5.02%; P < .0001), and acute renal failure (OAR vs HAR: 7.54% vs 5.17%; P = .03). In the PSM subgroup, the rates of spinal cord ischemic (OAR vs HAR: 5.75% vs 11.49%; P = .02), stroke (OAR vs HAR: 5.1% vs 17.35%; P = .01), and permanent paraplegia (OAR vs HAR: 2.79% vs 6.08%; P = .006) were lower in the OAR group than that in the HAR group. Although there was no statistically significant difference in 1-year survival rates (HAR vs OAR: hazard ratio [HR]: 1.54; P = .10), the 3-year and 5-year survivals were significantly higher in the OAR group than that in the HAR group (HAR vs OAR: HR: 1.69; P = .01; HAR vs OAR: HR: 1.68; P = .01). In the PSM subgroup, the OAR group was also significantly superior to the HAR group in terms of 3-year and 5-year survivals (HAR vs OAR: HR: 1.73; P = .04; HAR vs OAR: HR: 1.67; P = .04). The reintervention rate in the HAR group was significantly higher than that in the OAR group (OAR vs HAR: 8.24% vs 16.01%; P = .01). The most common reintervention was postoperative bleeding (8.07%) in the OAR group and endoleak (9.67%) in the HAR group.

CONCLUSIONS

Our meta-analysis revealed that debranching HAR was associated with fewer perioperative complications than the OAR group, except for postoperative permanent paraplegia, reintervention, and stroke events. The OAR group demonstrated better 3-year and 5-year survivals than the debranching HAR group. However, patients in the OAR group had fewer comorbid factors and were younger than those in the HAR group. High-quality studies and well-powered randomized trials are needed to further evaluate this evolving field.

Vertebral artery course variation leading to an insufficient proximal anchoring area for thoracic endovascular aortic repair

BACKGROUNDS

We aimed to demonstrate the feasibility of thoracic endovascular aortic repair for type B aortic dissection in patients with an insufficient proximal anchoring area due to the vertebral artery originating from the aortic arch.

METHODS

In this study, we report two patients with type B aortic dissection who were complicated with left vertebral artery course variation. Specifically, the left vertebral artery originated from the aortic arch. In these patients, the anchoring area (<15 mm) was not sufficient between the left vertebral artery and the ruptured aortic dissection.

RESULT

We reconstructed the left vertebral artery during horacic endovascular aortic repair. Both patients recovered well and were discharged without any adverse events.

CONCLUTION

Our experience shows that horacic endovascular aortic repair is feasible in patients with type B aortic dissection who have an insufficient proximal anchoring area due to the left vertebral artery originating from the aortic arch.

Tailored approach and outcomes of aortic arch reconstruction after acute type A dissection repair

OBJECTIVE

After limited root/ascending with or without hemiarch repair for acute type A aortic dissection (ATAAD), 20% to 30% of patients require distal reintervention, frequently for arch pathology. In this report, we describe an institutional algorithm for arch management after previous limited ATAAD repair and detail operative and long-term outcomes.

METHODS

From August 2005 to April 2021, 71 patients status post previous limited ATAAD repair underwent reoperative arch repair involving zones 1 to 3 for aneurysmal degeneration of residual arch dissection including complete cervical debranching with zone 0/1 thoracic endovascular aortic repair in 6 (8%), open total arch in 13 (18%), type I hybrid arch repair in 23 (32%), and type II/III hybrid arch repair in 29 (41%).

RESULTS

Mean age was 59 ± 12 years; time from index ATAAD repair to reoperation was 4 (interquartile range, 2-9) years. There were 2 (2.8%) in-hospital deaths and 2 (2.8%) postdischarge deaths within 30 days of surgery. Three patients suffered stroke (4.2%) and 2 (2.8%) had acute renal failure requiring dialysis. Overall Kaplan-Meier survival was 78%, 70%, and 58% at 1, 3, and 5 years, respectively. Institutional experience appeared to play a significant role in early and late outcomes, because there have been no operative mortalities in the past 9 years and improved survival of 87% versus 66%, 79% versus 58%, and 79% versus 40% at 1, 3, and 5 years in comparisons of the past 9 years with the previous era (P = .01).

CONCLUSIONS

Aneurysmal degeneration of residual arch dissection after limited ATAAD repair presents a complex reoperative challenge. An algorithmic operative approach tailored to patient anatomy and comorbidities yields excellent early and late outcomes, which continue to improve with increasing institutional experience.

Early and midterm outcomes of in situ fenestration via adjustable puncture needle for Ankura aortic stent graft: A single-center experience

OBJECTIVES

An analysis was conducted to demonstrate early and midterm outcomes of using adjustable puncture needle-based in situ fenestration (ISF) technique for Ankura aortic stent graft to reconstruct the supra-arch branch in thoracic endovascular aortic repair (TEVAR).

METHODS

A retrospective analysis of 68 cases of aortic lesions with insufficient proximal anchoring area admitted to our department from March 2017 to December 2021 was performed. In situ fenestration thoracic endovascular repair (TEVAR) was performed at the same time during the operation. Among them, there were fifty-eight cases of thoracic aortic dissection, seven cases of thoracic aortic aneurysm, and three cases of thoracic aortic ulcer. Intraoperative adjustable puncture with needle was used for the Ankura aorta stent graft to perform ISF and reconstruction of the supra-arch branch.

RESULTS

The success rate of ISF was 94.1% (64/68). Only in four cases, attempts were made to create ISF in the left subclavian artery (LSA), and all the four were unsuccessful because of sharp and tortuosity angle. Among them, forty-four cases were only LSA fenestration, and one case was left common carotid artery (LCCA) fenestration + LSA embolism. LSA + left vertebral artery (LVA) fenestration was performed in two cases, LSA fenestration +LCCA chimney was performed in fourteen cases, LCCA + LSA fenestration + innominate artery (INA) chimney was performed in one case, and LCCA fenestration + INA chimney + LSA embolism was performed in two cases. The overall neurologic event rate was 3.1% (spinal cord ischemia 0, with stroke observed in two cases). Postoperatively, one patient (1.6%) died on the third day after TEVAR due to the retrograde dissections. There were four cases of endoleak (6.3%; three type I and one type II). The average follow-up was 29.2 ± 14.4 months, and no patient died during the follow-up period. Three cases of endoleak disappeared, and one case did not increase further. In addition, other two cases of retrograde dissections were observed at 3 and 5 months after TEVAR. Fortunately, they were scheduled for emergency surgery with ascending aorta replacement and improved well. There was only one case of LSA occlusion after ISF which was reconstructed by endovascular treatment. Two patients were found with distal stent graft-induced new entries (dSINE), and TEVAR was performed again during the follow-up period.

CONCLUSION

Early and midterm outcomes demonstrated that ISF via the adjustable puncture needle device for the Ankura aorta stent graft is a feasible and effective treatment method, which can achieve high technical success and satisfactory short-term results.

Near-wall hemodynamic changes in subclavian artery perfusion induced by retrograde inner branched thoracic endograft implantation

Objective

Left subclavian artery (LSA)-branched endografts with retrograde inner branch configuration (thoracic branch endoprosthesis [TBE]) offer a complete endovascular solution when LSA preservation is required during zone 2 thoracic endovascular aortic repair. However, the hemodynamic consequences of the TBE have not been well-investigated. We compared near-wall hemodynamic parameters before and after the TBE implantation using computational fluid dynamic simulations.

Methods

Eleven patients who had undergone TBE implantation were included. Three-dimensional aortic arch geometries were constructed from the pre- and post-TBE implantation computed tomography images. The resulting 22 three-dimensional aortic arch geometries were then discretized into finite element meshes for computational fluid dynamic simulations. Inflow boundary conditions were prescribed using normal physiological pulsatile circulation. Outlet boundary conditions consisted of Windkessel models with previously published values. Blood flow, modeled as Newtonian fluid, simulations were performed with rigid wall assumptions using SimVascular's incompressible Navier-Stokes solver. We compared well-established hemodynamic descriptors: pressure, flow rate, time-averaged wall shear stress (TAWSS), the oscillatory shear index (OSI), and percent area with an OSI of >0.2. Data were presented on the stented portion of the LSA.

Results

TBE implantation was associated with a small decrease in peak LSA pressure (153 mm Hg; interquartile range [IQR], 151-154 mm Hg vs 159 mm Hg; IQR, 158-160 mm Hg; P = .005). No difference was observed in peak LSA flow rates before and after implantation: 40.4 cm³/ (IQR, 39.5-41.6 cm³/s) vs 41.3 cm³/s (IQR, 37.2-44.8 cm³/s; P = .59). There was a significant postimplantation increase in TAWSS (15.2 dynes/cm² [IQR, 12.2-17.7 dynes/cm²] vs 6.2 dynes/cm² [IQR, 5.7-10.3 dynes/cm²]; P = .003), leading to decreases in both the OSI (0.088 [IQR, 0.063 to -0.099] vs 0.1 [IQR, 0.096-0.16]; P = .03) and percentage of area with an OSI of >0.2 (10.4 [IQR, 5.8-15.8] vs 15.7 [IQR, 10.7-31.9]; P = .13). Neither LSA side branch angulation (median, 81°, IQR, 77°-109°) nor moderate compression (16%-58%) seemed to have an impact on the pressure, flow rate, TAWSS, or percentage of area with an OSI of >0.2 in the stented LSA.

Conclusions

The implantation of TBE produces modest hemodynamic disturbances that are unlikely to result in clinically relevant changes.

Comprehensive review of hybrid aortic arch repair with focus on zone 0 TEVAR and our institutional experience

Even with increasing operator experience and a better understanding of the disease and the operation, intervention for aortic arch pathologies continues to struggle with relatively higher mortality, reintervention, and neurologic complications. The hybrid aortic arch repair was introduced to simplify the procedure and improve the outcome. With recent industry-driven advances, hybrid repairs are not only offered to poor surgical candidates but have become mainstream. This review discusses the evolution of hybrid repair, terminology pertinent to this technique, and results. In addition, we aim to provide a pervasive review of hybrid aortic arch repairs with reference to relevant literature for a detailed understanding. We have also discussed our institutional experience with hybrid repairs.

Aortic Arch Repair Using Open and Hybrid Techniques: A Systematic Review

Early surgical intervention is critical for treatment of aortic arch aneurysms and dissections, but limited comprehensive data exist to define the optimal approach for surgical management with respect to postoperative outcomes. We conducted a systematic review of the 2 most common surgical approaches-total arch replacement and hybrid arch repair. We referenced the electronic PubMed database reporting on outcomes for these surgical approaches from inception to June 2022. Our initial search query returned a total of 2,517 records. All records were independently screened for adherence to our inclusion criteria and a total of 12 retrospective cohort studies were identified as appropriate for inclusion. Across the included studies, a total of 618 patients underwent hybrid repair, as compared to 2,104 patients who underwent total arch replacement. We found that most of the literature supported the findings of similar rates of permanent neurologic dysfunction, acute kidney injury, and short-term mortality between approaches and higher postoperative reintervention rates following hybrid repair. Reported outcomes of studies included in this review often conflicted regarding midterm and long-term survival, as well as hospital and intensive care unit length of stay following open and hybrid repair. Future studies should address midterm and long-term survival with a prospective study design.

Open arch surgery in the redo setting: contemporary outcomes

BACKGROUND

Aortic arch reconstruction after prior cardiac surgery is technically complex, especially after proximal aortic surgery. While multiple surgical adaptations in the redo setting have been described, traditional open reconstruction remains the most common approach with significant variability in outcomes in prior reports. This study describes institutional adaptations to surgical technique and perioperative care and assesses operative and long-term outcomes after redo-aortic arch repair in the modern era.

METHODS

Patients undergoing hemi- or total arch reconstruction after prior cardiac surgery (2005-2022) were identified from a prospectively maintained institutional database. Strategic adaptations in approach over the study interval included a shift towards Type II hybrid arch repair for patients with "mega-aorta," redo-cannulation of the axillary artery when necessary, and adoption of transfusion and early extubation protocols. Outcomes of interest included 30-day/in-hospital adverse events and actuarial long-term overall and aorta-specific survival.

RESULTS

The study cohort included 214 patients undergoing hemi-arch (N.=154, 72%) or total arch (N.=60, 28%) after prior cardiac surgery (50% prior proximal aortic surgery). Surgical indications included degenerative aneurysm (47%, N.=101), residual arch dissection after prior type A repair (29%, N.=61), acute or chronic type A dissection (18%, N.=39) or other (6%, N.=13). 30-day/in-hospital mortality was 6% (5% hemi-arch; 10% total arch) and stroke was 3% (3% hemi-arch; 2% total arch). At median follow-up of 56 months, overall 5- and 10-year survival was 76% and 58% (hemi-arch: 81%, 62%; total arch: 63%, 43%); aorta-specific survival was 91% and 90% (hemi-arch: 96%, 94%; total arch: 79%, 79%).

CONCLUSIONS

In this modern single-institution series, a systematic approach to redo-arch repair yields excellent operative outcomes and late aorta-specific survival. Reduced late overall survival reflects the comorbidity burden of this population. Open reconstruction continues to play an important role in reoperative arch repair in the modern era.

Outcomes of Great Vessel Debranching to Facilitate Thoracic Endovascular Aortic Repair

OBJECTIVES

With the expanding application of endovascular technology, the need to deploy into zone 0 has been encountered on occasion. This study evaluates the outcomes of great vessel debranching (GVD) as a method of extending the proximal landing zone (PLZ) to facilitate thoracic endovascular aortic repair (TEVAR).

METHODS

A single-center retrospective review of all patients who underwent GVD followed by TEVAR between May 2013 and December 2020 was conducted. The primary outcome was primary patency of all targeted vessels, with all-cause perioperative mortality as a secondary outcome. Kaplan-Meier analysis was used to account for censoring the mortality and primary patency. The extent of hybrid aortic repairs was characterized into type I: GVD + TEVAR without ascending aorta or aortic arch reconstruction; type II: GVD + TEVAR with ascending aorta reconstruction; and type III: GVD + TEVAR with ascending aorta and aortic arch reconstruction with an elephant trunk (surgical or "frozen").

RESULTS

There were 42 patients (23 males [54.8%], mean age of 62.2 ± 11.2 years) who underwent GVD with 122 vessels revascularized (42 innominate, 42 left common carotid [LCCA], and 38 left subclavian [LSA] arteries). The indication for TEVAR was aneurysmal degeneration from aortic dissection in 32 (76.2%) patients, thoracic aneurysm in 9 (21.4%) patients, and perforated aortic ulcer in 1 (2.4%) patient. Median duration between GVD and TEVAR was 82 days. Mean follow-up was 25.7 ± 23.5 months. Type I repair was performed in 4, type II in 16, and type III in 22 patients. Perioperative mortality, stroke, and paraplegia rates were 9.5%, 7.1%, and 2.4%, respectively. Neither the extent of repair (p = 0.80) nor a prior history of aortic repair (p = 0.90) was associated with early mortality. Late deaths (>30 days) occurred in 6 of 38 patients who survived the perioperative period. At 36 months, the survival estimate was 68.6% (95% CI: 45.7% - 83.4%); the overall primary patency of the innominate artery, LCCA, and LSA was 100%, 89.5%, and 94.1%, respectively. The primary assisted patency rate was 100% for all vessels.

CONCLUSIONS

GVD is a safe and effective means of extending the PLZ into zone 0 with outstanding primary patency rates. Further studies are needed to confirm the safety and longer-term durability in these patients.

Impact of frailty on early and mid-term outcomes of hybrid aortic arch repair

PURPOSE

The purpose of this study was to investigate the impact of frailty on the clinical outcomes of hybrid aortic arch repair with debranching of the supra-aortic arteries.

METHODS

Consecutive patients ≥ 75 years old who underwent hybrid aortic arch repair from January 2010 to December 2019 were retrospectively analyzed. Using the Canadian Study of Health and Aging (CSHA) scale, all patients with a CSHA scale score > 4 were defined as frail. The frail patients (FP) group and the non-frail patients (NFP) group were compared regarding the early and mid-term outcomes of hybrid aortic arch repair.

RESULTS

A total of 84 patients were included. The early postoperative results were not markedly different between the groups, except that the rate of transfer to a rehabilitation hospital was higher in the FP group than in the NFP group. The survival at 5 years was significantly lower in the FP group at 43.0% than in the NFP group at 67.7% (P = 0.015). However, the freedom from aorta-related death was not significantly different between the two groups.

CONCLUSION

Frailty did not affect the short-term outcomes of hybrid aortic arch repair; however, the mid-term outcomes, including the survival, of the frail patients were significantly worse than those of the non-frail patients, mostly because of non-aorta-related causes.

Current state of hybrid solutions for aortic arch aneurysms

Since its inception in the early 2000s, hybrid arch repair (HAR) has evolved from a novel approach to a well-established treatment modality for aortic arch pathology in appropriately selected patients. HAR procedures have been proposed as a means to circumvent the perioperative morbidity and mortality associated with open total arch replacement. These procedures, all of which remain off-label applications of approved endograft technology, combine more conventional open surgical techniques, to create endograft landing zones, with thoracic endovascular aortic repair to exclude the aortic pathology from the circulation. The current classification system for HAR was proposed in 2013 and consists of three types, designated by the Roman numerals I, II and III. The current system has become outdated, however, with the advent of newer technologies, and herein we propose a new, updated classification system that is more encompassing with regards to the broad array of options available to treat aortic arch disease. Likewise, an institutional algorithm to guide patient and operative selection for HAR is presented. Patients are considered for HAR if they have either high-risk comorbidities or high-risk anatomy, with an important feature of the algorithm being that any decisions about repair strategy should be made by a surgical team with expertise in both open and endovascular techniques. Despite being performed for nearly two decades, the evidence around HAR consists mainly of single center series (level B-C evidence) with no randomized controlled trials. The data suggest HAR to be a safe alternative to open repair with acceptable short and mid-term results. As we as aortic surgeons continue to move towards less invasive approaches, both conventional open and hybrid techniques will remain important tools in the toolbox for arch repair, although the advent of multi-branched arch endografts will almost certainly reduce the extent of open or hybrid repair in many patients and eliminate it altogether in others.

Evaluation of the Gore TAG thoracic branch endoprosthesis in the treatment of proximal descending thoracic aortic aneurysms

BACKGROUND

Thoracic endovascular aortic repair has radically transformed the treatment of descending thoracic aortic aneurysms. However, when aneurysms involve the aortic arch in the region of the left subclavian artery, branch vessel preservation must be considered. Branched aortic endografts have provided a new option to maintain branch patency.

METHODS

Six investigative sites enrolled 31 patients in a nonrandomized, prospective investigational device exemption feasibility trial of a single branched aortic endograft for the management of aneurysms that include the distal aortic arch. The Gore TAG thoracic branch endoprosthesis (W. L. Gore & Associates, Inc, Flagstaff, Ariz), an investigational device, allows for graft placement proximal to the left subclavian artery and incorporates a single side branch for left subclavian perfusion.

RESULTS

All 31 patients (100%) had undergone successful implantation of the investigational device in landing zone 2. Men slightly outnumbered women (51.6%). Their average age was 74.1 ± 10.4 years. The aneurysm morphology was fusiform in 12 and saccular in 19 patients, with a mean maximum aortic diameter of 54.8 ± 10.9 mm. The mean follow-up period for the cohort was 25.2 ± 11.1 months. We have reported the patient outcomes at 1 month and 1 year. At 1 month, the side branch patency was 100% and the freedom from core laboratory-reported device-related endoleak (types I and III) was 96.7%, without 30-day death or permanent paraplegia. One patient experienced a procedure-related stroke. Through 1 year, five patients had died; none of the deaths were related to the device or procedure (clinical endpoint committee adjudicated). One thoracic reintervention was required. No conversions were required, and no aneurysm growth (core laboratory) was reported. One case of the loss of side branch patency was diagnosed in the left subclavian artery in an asymptomatic individual from computed tomography at 6 months, with no reported subsequent adverse events due to loss of patency. Endoleaks were reported by the core laboratory in five patients at 12 months (two, type II; and three, indeterminate).

CONCLUSIONS

The present investigational device exemption feasibility study has reported the preliminary results of the use of a single side branch endograft to treat patients with proximal descending thoracic aortic aneurysms.

Outcomes Of Chimney Technique For Aortic Arch Diseases: A Single-Center Experience With 226 Cases

Purpose

The goal of present study is to document our single-center experience with chimney technique for aortic arch diseases.

Patients and methods

From August 2012 to October 2017, 226 patients (mean age 54±12 years; 197 men) with aortic arch diseases underwent thoracic endovascular aortic repair combined with chimney stents. The aortic stent-grafts were deployed in zone 0 (n=22), zone 1 (n=13), or zone 2 (n=191).

Results

The technical success rate was 84% (189/226) and immediate type Ia endoleak (ELIa) happened in 37 (16%) patients. The 30-day mortality and morbidity rates were 2% (4/226) and 4% (8/226), respectively. Major adverse events include four major strokes, three spinal cord ischemia and one aortic rupture in the early-term. The clinical and imaging follow-up rates were 98% (218/222) and 78% (173/222), respectively. The average lengths of clinical and imaging follow-up were 22±16 months and 20±15 months, respectively. Chimney stent obstructions in left subclavian arteries were recorded in six (3%) patients. During follow-up, five patients died (2%) and two major strokes occurred (1%). One patient (0.5%) underwent reintervention.

Conclusion

The current study documented that the chimney technique is effective and safe for treating aortic arch diseases in different aortic zones. Cautions are needed to assess the permanency of chimney stent and to reduce the immediate ELIa rate.

A Case of Type I Debranching Complicated by Anastomotic Pseudoaneurysm: Do Not Ask Too Much of the Ascending Aorta

Treatment of aortic arch aneurysm with standard open surgery is technically demanding, and associated morbidity and mortality are not insignificant. In high-risk patients, hybrid procedures with debranching and reimplantation or bypass of the aortic arch vessel followed by thoracic endovascular aortic repair (TEVAR) in the aortic arch represent a valid alternative to open surgery. However, when the ascending aorta is mildly dilated, the risk of retrograde dissection increases sharply. Here, we report a case of thoracic aortic aneurysm, with normal ascending aorta diameter, treated with Type I debranching and anterograde TEVAR complicated by anastomotic pseudoaneurysm and acute endocarditis, treated ultimately with ascending aortic repair and aortic valve replacement.

Long-term stroke incidence in proximal thoracic aorta aneurysm survivors

BACKGROUND

Aneurysm of proximal thoracic aorta (pTAA) is an often indolent, yet fatal disease. Although advancements in aneurysmal repair techniques have increased long-term survival rates, studies have proven that there are increases in perioperative risk for stroke incidence after pTAA surgery. Conversely, there is little evidence regarding the long-term stroke incidence in pTAA individuals, which strongly influences the morbidity, mortality, and usage of antithrombotic agents.

METHODS

Using the Taiwan National Health Insurance Research Database, a nationwide population-based cohort, we recruited 3013 pTAA survivors hospitalized from 1 January 2000 to 31 December 2012. To ensure study cohort quality, only patients aged 20 years and above who underwent aneurysmal repair surgery are included. The control cohort is identified by matching background features (comorbidities, age, gender) at a 1:4 ratio through the use of frequency matching. The primary outcomes include incidence of ischemic stroke and intracranial hemorrhage one month after aneurysmal repair surgery.

RESULTS

The mortality of pTAA survivors is nearly twice of the matched controls despite aneurysmal repair (28.5 % vs. 15.2%, p < 0.001). Long-term follow-up of participants indicated that pTAA survivors had a higher risk for hemorrhage stroke (adjusted hazard ratio (aHR): 1.93; 95% confidence interval (CI): 1.47-2.53), but no significant increase in risk for ischemic stroke (aHR: 1.07; 95% CI: 0.92-1.25). Hemorrhagic stroke occurrence was found to be associated with age and diabetes mellitus. Comparison on hemorrhagic stroke subtypes between study and matched cohorts showed no statistical differences in intracerebral hemorrhage and subarachnoid hemorrhage.

CONCLUSIONS

Despite the advancement of aneurysmal repair surgery, this study suggests that pTAA patients may still face an increased risk of hemorrhage stroke. Further investigation is warranted to provide better long-term care for the pTAA population.

Debranching of Supra-aortic Vessels via Femoral Artery Inflow for Late Ascending Aortic Rupture

A 56-year-old man with a history of Marfan's syndrome, total arch replacement, descending thoracic endovascular aortic repair, and twice redo sternotomy for pseudoaneurysm repair, presented with a pulsatile chest mass secondary to a contained rupture of the ascending aorta. The patient underwent supra-aortic debranching via the superficial femoral artery and ascending thoracic stent-graft placement under continuous transesophageal echocardiography. Completion angiography demonstrated successful exclusion of the contained rupture. Postoperatively, the patient was neurologically intact, the pulsatile mass resolved, and the bypass grafts remained patent. Chronic respiratory failure and multidrug-resistant pneumonia led to late mortality. This case demonstrates that hybrid repair is effective in the emergent setting of ascending aortic rupture. Debranching of the ascending arch using the superficial femoral artery as inflow is feasible and provides adequate cerebral perfusion despite the length of the bypass. The use of transesophageal echocardiography during stent-graft deployment allows precise device placement in the high-risk area of the ascending aorta proximal to the innominate artery.

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

OBJECTIVE

To report outcomes of the chimney technique for preservation of the left subclavian artery (LSA) in patients with type B aortic dissection (TBAD).

METHODS

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.

RESULTS

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.

CONCLUSION

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.

A review of endovascular treatment of thoracic aorta disease

INTRODUCTION

The development of thoracic endovascular aortic repair has altered the approach and reduced the risk of treating the majority of descending thoracic aortic conditions. Primarily developed for the exclusion of thoracic aortic aneurysms, it is now used in place of open repair surgery for most descending thoracic aortic diseases, and has also been used to treat aortic arch diseases in selected cases.

METHODS

A literature search was conducted of Medline and Embase databases from January 2007 to February 2017, using the key words 'aortic disease', 'thoracic aorta' and 'endovascular repair'; 205 articles were identified, of which 25 studies were selected for review based on their relevance.

FINDINGS

The key findings of the indications, techniques, outcomes, complications and comparisons with open surgical repair were extracted from the published studies and are summarised in this review. Thoracic endovascular aortic repair is the preferred choice of intervention for patients with descending thoracic aortic disease. With time, it has improved to be safer and has the potential to expand aortic treatment choices in future.

Long-term survival and related outcomes for hybrid versus traditional arch repair-a meta-analysis

Background

Surgical interventions for aortic aneurysm and dissection remain associated with high risk of mortality and morbidity. Advances in operative techniques have led to a variety of options for the cardiac surgeon, including endovascular and hybrid approaches. Debate remains over which of these techniques provide optimal outcomes for the patient. The present systematic review and meta-analysis aims to evaluate long term patient survival and identify short-term outcomes for conventional (open) aortic arch repair and hybrid aortic arch repair (HAR).

Methods

An electronic literature search was conducted according to predefined inclusion criteria for hybrid and conventional aortic arch repair surgery. Digitized survival data was extracted from identified studies' Kaplan-Meier curves and used to re-create individual patient data for aggregated survival analysis. Post-operative morbidity and mortality were analyzed using random-effects model meta-analysis.

Results

Nine studies were included, containing 841 hybrid arch repair and 1,182 conventional arch repair patients. Pooled Kaplan-Meier analysis of all patients demonstrated higher survival in hybrid arch repair patients than conventional arch repair patients, however, this was noted to be sensitive to results from a particular study. Overall results showed for the hybrid repair cohort, survival at 1, 2, 3, 5 and 7 years was 87%, 85%, 83%, 78% and 75%, respectively. Survival in the conventional repair cohort at 1, 2, 3, 5 and 7 years was 84%, 82%, 80%, 75% and 71%, respectively. Statistically significant findings from meta-analysis showed hybrid arch repair was associated with lower risk of re-operation for bleeding, while conventional arch repair was associated with reduced risk of spinal cord injury.

Conclusions

Pooled Kaplan-Meier analysis of all studies showed long-term survival outcomes for hybrid and conventional aortic arch repair patients are heterogeneous and sensitive to the results of particular studies. Superior results from particular centres and the low number of comparative studies mean that more data is required to make definitive findings with regards to the long-term survival outcomes of either procedure. Hybrid arch repair was associated with lower risk of re-operation for bleeding, while conventional arch repair was associated with lower risk of spinal cord injury. Surgeons should consider their own center's experience and patient suitability when deciding between hybrid or conventional aortic repair techniques.

A Feasibility Study of a New Unibody Branched Stent Graft Applied to Reconstruct the Canine Aortic Arch

OBJECTIVES

The aim was to evaluate the feasibility and safety of a new unibody branched stent graft for the reconstruction of the canine aortic arch.

METHODS

The unibody branched stent grafts included single branched stent grafts and double branched stent grafts. The main stent graft and branched limbs were sutured together. The branched stent grafts were folded into the introducer system, which consisted of a double channel catheter, a detachable sleeve, and an introducer sheath. The branched stent grafts were introduced and deployed into the aortic arch by the delivery system. Twenty adult mongrel dogs were used for the experiments. Ten dogs were implanted with single branched stent grafts; the other 10 were implanted with double branched stent grafts. The surviving animals were followed up for 3 months. Computed tomography angiography (CTA) was performed to observe the status of the branched stent grafts.

RESULTS

All the unibody branched stent grafts were successfully implanted into the canine aortic arches. The technical success rate was 100%. There was no cerebral infarction, paraplegia or incision infection. CTA showed that all the branched stent grafts were patent; there was no endoleak or stent migration.

CONCLUSIONS

The unibody branched stent graft system could be used to reconstruct the aortic arch. The animal experimental procedures demonstrated the safety and feasibility of the unibody branched stent graft system.

Hybrid Reconstruction of the Aortic Arch Using a Double-Branched Stent-Graft in a Canine Model

Purpose: To report the results of a hybrid approach to aortic arch repair using an innovative unibody double-branched stent graft in a canine model.Materials and methods: The stent-graft system consists of two parts: the main body and two branches for reconstruction of the supra-arch branches. There is a 2-cm-long suturing portion at the proximal end of the main body. Twenty adult German sheep dogs underwent a hybrid surgical treatment to place the stent-grafts into the proximal descending aorta and the supra-arch branches. Outcomes were assessed by operative mortality, complications, imaging studies, and histomorphometric analyses.Results: Placement of the stent-graft was performed successfully in all dogs without complications. One dog died of respiratory failure due to early extubation. The other dogs survived to 6 months without complications, at which time they were sacrificed. The mean cardiopulmonary bypass time was 80.3 ± 7.3 mins and hypothermic circulatory arrest time was 10.7 ± 1.9 min. The average blood loss was 373.5 mL. At 6 months, postoperative aortic imaging indicated that the main body and branches of the stent-graft were fully open and in satisfactory position. No migration, deformation, or endovascular leakage was observed. Histomorphometric results showed normal arrangement of medial and adventitial elastic fibers, moderately proliferated intima, with or without neo-microvessels, and microscopic morphological changes in internal elastic lamina.Conclusions: These results demonstrate that it is possible and safe to reconstruct the aortic arch with the novel open-branched stent-graft placement.

Infrarenal aortic repair with or without false lumen intentional placement of endografts for hybrid management of complex aortic dissection

OBJECTIVE

Aortic dissection (AD) often involves the infrarenal aorta. We review our experience with open infrarenal aortic repair with or without false lumen intentional placement (FLIP) of endografts in the proximal dissected aorta as part of a hybrid strategy to treat complex AD.

METHODS

A prospectively maintained database of patients undergoing intervention for AD was reviewed. Data regarding diagnosis, imaging features, nature of the infrarenal repair (one- vs two-stage procedure), endoleaks, need for additional interventions, morbidity, and mortality were collected.

RESULTS

Between 2006 and 2017, there were 16 patients with AD with thoracoabdominal aortic aneurysm (TAAA), malperfusion, or both who underwent open infrarenal aortic repair or replacement combined with endovascular repair in a single- or multiple-stage procedure. Fifteen patients had a chronic AD and one patient had an acute AD. The most common indication for intervention was absolute size or rapid growth of the abdominal, thoracic, or thoracoabdominal aortic aneurysm (65%). In four patients with AD, the infrarenal replacement surgical graft was used as a common distal seal zone, allowing FLIP of an endograft to treat the proximal AD. Ten (62%) cases were done in two or more stages. Three patients had infrarenal aortic replacement with debranching only. In two of these patients, the proximal dissected aorta has remained stable without aneurysmal degeneration. One patient died as a result of rupture of his aneurysm while awaiting the second stage (perioperative mortality, 6%). Patients were observed from 1 month to 7 years. One patient had a stable type II endoleak, and one patient required subsequent replacement of ascending aortic arch for aneurysmal disease. One patient died of unrelated causes on follow-up.

CONCLUSIONS

Hybrid infrarenal aortic repair for treatment of complex AD can be performed with low morbidity and mortality and excellent medium-term results. This strategy can resolve malperfusion while simultaneously creating a landing zone using the false lumen as the conduit for the stent graft (FLIP) in selected patients. The FLIP technique allows full expansion of the endograft, potential preservation of lumbar and intercostal artery flow, and exclusion of the weaker false lumen while, in some cases, decompressing and thus stabilizing the proximal dissected aorta.

Neurophysiological Intraoperative Monitoring During Aortic Arch Surgery

Circulatory management during replacement of the aortic arch is complex and involves a period of circulatory arrest to provide a bloodless field during arch vessel anastomosis. To guard against ischemic brain injury, tissue metabolic demand is reduced by systemically cooling the patient prior to circulatory arrest. Neurophysiological intraoperative monitoring (NIOM) is often used during the course of these procedures to provide contemporaneous assessment of brain status to help direct circulatory management decisions and detect brain ischemia. In this review, we discuss the characteristics of electrocerebral activity through the process of cooling, circulatory arrest, and rewarming as depicted through commonly used NIOM modalities, including electroencephalography and peripheral nerve somatosensory-evoked potentials. Attention is directed toward the role NIOM has traditionally played during deep hypothermic circulatory arrest, where it is used to define the point of electrocerebral inactivity or maximal cerebral metabolic suppression prior to initiating circulatory arrest while also discussing the evolving utility of NIOM when systemic circulatory arrest is initiated at more moderate degrees of hypothermia in conjunction with regional brain perfusion. The use of cerebral tissue oximetry by near-infrared spectroscopy as an alternative NIOM modality during surgery of the aortic arch is addressed as well. Finally, special considerations for NIOM and the detection of spinal cord ischemia during hybrid aortic arch repair and emerging operative techniques are also discussed.