Ascending and Transverse Aortic Arch Repair

Anesthetic Management for Proximal Aortic Repair

Surgical repair of the proximal aorta is a complex endeavor, requiring cardiopulmonary bypass (CPB) and often the use of hypothermic circulatory arrest (HCA). In addition to the normal considerations for patients undergoing cardiopulmonary bypass, additional challenges include cerebral and end-organ protection during periods of circulatory arrest. This review aims to provide an up-to-date, evidence-based review on anesthetic management for proximal aortic repair.

Early Experience With Fenestration Modification of Castor Branched Stent-Graft for Aortic Arch Diseases

PURPOSE

This study aimed to assess the safety and viability of combining branched stent graft with fenestrated thoracic endovascular aortic repair (TEVAR) in treating aortic arch lesions.

MATERIALS AND METHODS

The cohort included patients presenting with aortic arch lesions who underwent treatment with a combination of branched stent graft and fenestrated TEVAR between July 2020 and November 2022. Technical success was defined as the precise deployment of the stent graft, maintenance of branch vessel patency, and the absence of type I endoleak. The secondary outcomes examined were complications and all-cause mortality.

RESULTS

The study cohort comprised 21 patients (average age: 61.0±14.8 years) with aortic arch lesions from 3 tertiary care hospitals. The aortic arch lesions encompassed aortic dissection (N=8), aortic aneurysm (N=8), pseudoaneurysm (N=1), intramural hematoma (N=1), and penetrating aortic ulcer (N=3). The technical success rate achieved was 95.2% (20/21). Failure in one case was due to an intraoperative type I endoleak, which was rectified with an additional stent graft placement. The 30-day mortality rate was 4.8% (1/21). One patient suffered a stroke but responded well to medical intervention. The median hospital stay was 10.9±5.4 days. During the follow-up period, one death (4.8%) was associated with aortic complications. A type II endoleak was observed and managed with close monitoring. Two patients underwent re-interventions for retrograde type A dissection and stent migration, respectively. No occlusions were observed in the target branch arteries.

CONCLUSIONS

The combination of branched stent graft with fenestrated TEVAR emerges as a viable strategy for addressing specific lesions in the aortic arch.

CLINICAL IMPACT

This study demonstrates the feasibility of using branched stent grafts with fenestrated TEVAR for treating aortic arch lesions, achieving a technical success rate of 95.2%. Compared to traditional open surgery, this innovative, minimally invasive approach reduces perioperative mortality and complications, such as stroke and spinal cord ischemia. For clinicians, it offers a viable alternative for patients unfit for open repair, particularly in complex aortic arch cases. While the initial outcomes are promising, further research is needed to assess long-term durability and risks, including stent graft migration and late endoleak, ensuring the technique's safety and efficacy over time.

Open, endovascular or hybrid repair of aortic arch disease: narrative review of diverse strategies with diverse options

OBJECTIVES

The management of aortic arch disease is complex. Open surgical management continues to evolve, and the introduction of endovascular repair is revolutionizing aortic arch surgery. Although these innovative techniques have generated the opportunity for better outcomes in select patients, they have also introduced confusion and uncertainty regarding best practices.

METHODS

In New York, we developed a collaborative group, the New York Aortic Consortium, as a means of cross-linking knowledge and working together to better understand and treat aortic disease. In our meeting in May 2023, regional aortic experts and invited international experts discussed the contemporary management of aortic arch disease, differences in interpretation of the available literature and the integration of endovascular technology into disease management. We summarized the current state of aortic arch surgery in this review article.

RESULTS

Approaches to aortic arch repair have evolved substantially, whether it be methods to reduce cerebral ischaemia, improve haemostasis, simplify future operations or expand options for high-risk patients with endovascular approaches. However, the transverse aortic arch remains challenging to repair. Among our collaborative group of cardiac/aortic surgeons, we discovered a wide disparity in our practice patterns and our management strategies of patients with aortic arch disease.

CONCLUSIONS

It is important to build unique institutional expertise in the context of complex and evolving management of aortic arch disease with open surgery, endovascular repair and hybrid approaches, tailored to the risk profiles and anatomical specifics of individual patients.

Short- and long-term results of total arch replacement: Comparison between island and debranching techniques

OBJECTIVE

The 2 most acceptable techniques for reimplantation of the supra-aortic vessels in total arch replacement include the branched graft technique (debranching) or en bloc technique (island). We aim to review our experience with total arch replacement and report short- and long-term outcomes from a high-volume center dedicated to surgery for the thoracic aorta.

METHODS

The aortic surgery database was queried to identify all consecutive patients undergoing total arch replacement between 1997 and 2022. Of the 426 patients who underwent total arch replacement, 303 (71%) received the island technique and 123 (29%) received the debranching approach. Operative and long-term outcomes were compared using multivariable models.

RESULTS

The debranching group was younger (64 ± 14 years vs 69 ± 12 years, P = .001), had undergone more previous cardiac operations (54.5% vs 27.4%, P < .001), and had more connective tissue disorder (20.3% vs 4.6%, P < .001). The debranching approach was associated with longer total circulatory arrest time (47 ± 15 minutes vs 37 ± 10 minutes, P < .001) and cardiac ischemic time (116 ± 41 minutes vs 100 ± 37 minutes, P < .001). More patients in the debranching group received blood products intraoperatively or postoperatively (56.1% vs 42.9%, P = .018). All other early outcomes did not differ between groups. Overall operative mortality was 1.4% (2.4% vs 1%, P = .486); the incidence of major postoperative complications was 6.3% (5.7% vs 6.6%, P = .897). Ten-year survival was 80% (78% vs 80.9%, log-rank P = .356). Multivariable Cox regression analysis demonstrated that neither surgical approach was associated with survival advantage (hazard ratio, 1.18; 0.73-1.89; P = .495).

CONCLUSIONS

Debranching requires a longer operative time, with similar early and long-term outcomes. Preoperative comorbidity, not surgical technique, predicts major adverse events and long-term survival.

Cerebral Protection Strategies and Stroke in Surgery for Acute Type A Aortic Dissection

Background: Perioperative stroke remains a devastating complication in the operative treatment of acute type A aortic dissection. To reduce the risk of perioperative stroke, different perfusion techniques can be applied. A consensus on the preferred cerebral protection strategy does not exist. Methods: To provide an overview about the different cerebral protection strategies, literature research on Medline/PubMed was performed. All available original articles reporting on cerebral protection in surgery for acute type A aortic dissection and neurologic outcomes since 2010 were included. Results: Antegrade and retrograde cerebral perfusion may provide similar neurological outcomes while outperforming deep hypothermic circulatory arrest. The choice of arterial cannulation site and chosen level of hypothermia are influencing factors for perioperative stroke. Conclusions: Deep hypothermic circulatory arrest is not recommended as the sole cerebral protection technique. Antegrade and retrograde cerebral perfusion are today’s standard to provide cerebral protection during aortic surgery. Bilateral antegrade cerebral perfusion potentially leads to superior outcomes during prolonged circulatory arrest times between 30 and 50 min. Arterial cannulation sites with antegrade perfusion (axillary, central or carotid artery) in combination with moderate hypothermia seem to be advantageous. Every concept should be complemented by adequate intraoperative neuromonitoring.

Neuroprotection during Open Aortic Arch Surgery: Cerebral Perfusion Methods and Temperature

Neuroprotection is important in open aortic arch surgery because of the dependence of brain tissues on cerebral perfusion. Therefore, several techniques have been developed to reduce cerebral ischemia and improve outcomes in open aortic arch surgery. In this review, I describe various neuroprotective strategies, such as profound and deep hypothermic circulatory arrest, selective antegrade cerebral perfusion, retrograde cerebral perfusion, and lower body circulatory arrest; compare their advantages and disadvantages, and discuss their evolution and current status by reviewing relevant literature.

Evaluation of Different Cannulation Strategies for Aortic Arch Surgery Using a Cardiovascular Numerical Simulator

Aortic disease has a significant impact on quality of life. The involvement of the aortic arch requires the preservation of blood supply to the brain during surgery. Deep hypothermic circulatory arrest is an established technique for this purpose, although neurological injury remains high. Additional techniques have been used to reduce risk, although controversy still remains. A three-way cannulation approach, including both carotid arteries and the femoral artery or the ascending aorta, has been used successfully for aortic arch replacement and redo procedures. We developed circuits of the circulation to simulate blood flow during this type of cannulation set up. The CARDIOSIM© cardiovascular simulation platform was used to analyse the effect on haemodynamic and energetic parameters and the benefit derived in terms of organ perfusion pressure and flow. Our simulation approach based on lumped-parameter modelling, pressure-volume analysis and modified time-varying elastance provides a theoretical background to a three-way cannulation strategy for aortic arch surgery with correlation to the observed clinical practice.

Aortic Risks Prediction Models after Cardiac Surgeries Using Integrated Data

The complications of thoracic aortic disease include aortic dissection and aneurysm. The risks are frequently compounded by many cardiovascular comorbidities, which makes the process of clinical decision making complicated. The purpose of this study is to develop risk predictive models for patients after thoracic aneurysm surgeries, using integrated data from different medical institutions. Seven risk features were formulated for prediction. The CatBoost classifier performed best and provided an ROC AUC of 0.94–0.98 and an F-score of 0.95–0.98. The obtained results are widely in line with the current literature. The obtained findings provide additional support for clinical decision making, guiding a patient care team prior to surgical treatment, and promoting a safe postoperative period.

Matched comparison of 3 cerebral perfusion strategies in open zone-0 anastomosis for acute type A aortic dissection

OBJECTIVES

The present study aims to investigate outcomes after the surgical treatment of acute type A aortic dissection in regard to three available selective cerebral perfusion strategies.

METHODS

From 2000 to 2019, patients were selected based on the employment of either retrograde cerebral perfusion (RCP), unilateral antegrade cerebral perfusion (uACP) or bilateral antegrade cerebral perfusion (bACP) during open zone-0 anastomosis. Propensity score TriMatch analysis considering several preoperative and intraoperative variables was used to identify well-balanced triplets. The primary end point of the study was a new cerebral operation-related neurologic deficit.

RESULTS

Operative times (operation time, cardiopulmonary bypass time, reperfusion time) were significantly longer in the RCP group, in which deeper hypothermia was applied (27.5 [24-28], 28 [26-28] and 16 [16-17]°C for uACP, bACP and RCP, respectively, P-value <0.001). The RCP group showed higher red blood cell concentrates and fresh frozen plasma transfusion rates. No significant difference of new cerebral operation-related neurologic deficit was observed between the 3 groups (12.9% vs 12.9% vs 11.3% for RCP, uACP and bACP, P-value = 0.86). In addition, 30-day mortality showed similar distribution independently of the cerebral perfusion strategy adopted (17.7% vs 14.5% vs 17.7% for RCP, uACP and bACP, P-value = 0.86).

CONCLUSIONS

However, based on a small sample size, the comparison showed no relevant differences in terms of neurologic outcome and 30-day mortality, confirming RCP, uACP and bACP as safe and reproducible selective cerebral perfusion strategies in surgery for acute type A aortic dissection.

Development of aortic arch surgery in Bologna and reflections on current strategy of cerebral protection

Complications after open arch repair much decreased over time thanks to better methods of organ and cerebral protection. The crossroads was the introduction of antegrade cerebral perfusion as a method of cerebral protection. Other intraoperative techniques also contributed to facilitate arch reconstruction, such as performing circulatory arrest at higher core temperature, using hybrid grafts or endografts, and monitoring cerebral functions during the procedure. As part of this exciting process, we go back in Bologna in the early 1970s to relive some of these fundamental steps on aortic arch surgery. Today a large number of issues on cerebral protection remain for which we have incomplete responses. Probably, a super specialized approach and endovascular techniques will continue to improve the quality of care of patients with different arch pathologies.

Alternative Approach for Cerebral Protection during Complex Aortic Arch and Redo Surgery

Total arch replacement remains a very demanding surgical procedure. It can be associated with reasonable long-term outcomes but carries serious perioperative complications. Aortic arch surgery has progressed in recent years to a wider adoption of reproducible and reliable techniques. Conventional open, surgical aortic arch replacement is currently offered to the majority of patients, although hybrid and wholly endovascular techniques are gaining popularity. With regards to open arch replacement, the nuances of surgical technique, the mode of cannulation and the optimal cerebral protection protocols remain a matter of debate. We propose an alternative cannulation approach facilitated by the cooperation between cardiac and vascular surgeons. A three-way arterial cannulation including both carotid arteries and the femoral artery (or ascending aorta) is the key feature of this approach. A case series of complex patients is presented to show both the feasibility and relative safety of a standardised new approach with a 100% technical success rate and a 16% 30-day mortality. The three-way cannulation approach may have a role to play for complex and extensive procedures requiring prolonged cerebral protection. We believe that a shared skill set from cardiac and vascular specialists is essential for the safe management and successful outcomes using this adaptive technique.

Hybrid repair versus conventional open repair for thoracic aortic arch aneurysms

BACKGROUND

Thoracic aortic arch aneurysms (TAAs) can be a life-threatening condition due to the potential risk of rupture. Treatment is recommended when the risk of rupture is greater than the risk of surgical complications. Depending on the cause, size and growth rate of the TAA, treatment may vary from close observation to emergency surgery. Aneurysms of the thoracic aorta can be managed by a number of surgical techniques. Open surgical repair (OSR) of aneurysms involves either partial or total replacement of the aorta, which is dependent on the extent of the diseased segment of the aorta. During OSR, the aneurysm is replaced with a synthetic graft. Hybrid repair (HR) involves a combination of open surgery with endovascular aortic stent graft placement. Hybrid repair requires varying degrees of invasiveness, depending on the number of supra-aortic branches that require debranching. The hybrid technique that combines supra-aortic vascular debranching with stent grafting of the aortic arch has been introduced as a therapeutic alternative. However, the short- and long-term outcomes of HR remain unclear, due to technical difficulties and complications as a result of the angulation of the aortic arch as well as handling of the arch during surgery.

OBJECTIVES

To assess the effectiveness and safety of HR versus conventional OSR for the treatment of TAAs.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL and AMED databases and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 22 March 2021. We also searched references of relevant articles retrieved from the electronic search for additional citations.

SELECTION CRITERIA

We considered for inclusion in the review all published and unpublished randomised controlled trials (RCTs) and controlled clinical trials (CCTs) comparing HR to OSR for TAAs.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened all titles and abstracts obtained from the literature search to identify those that met the inclusion criteria. We retrieved the full text of studies deemed as potentially relevant by at least one review author. The same review authors screened the full-text articles independently for inclusion or exclusion.

MAIN RESULTS

No RCTs or CCTs met the inclusion criteria for this review.

AUTHORS' CONCLUSIONS

Due to the lack of RCTs or CCTs, we were unable to determine the safety and effectiveness of HR compared to OSR in people with TAAs, and we are unable to provide high-certainty evidence on the optimal surgical intervention for this cohort of patients. High-quality RCTs or CCTs are necessary, addressing the objective of this review.

Technical Aspects of Fenestrated Arch TEVAR With Preloaded Fenestration

Fenestrated thoracic endovascular aortic repair (f-TEVAR) has expanded the possibilities of endovascular arch repair, allowing treatment of pathologies involving the aortic arch that require sealing in Ishimaru zones 1 and 2. The growing number of implantations has increased physician experience and helped identify critical procedural points, mainly wire entanglement and device malrotation. Herein we describe a step-by-step approach to a f-TEVAR procedure with the Zenith fenestrated preloaded thoracic endograft, identifying potential pitfalls and suggesting problem-solving solutions.

Mild hypothermic circulatory arrest with selective cerebral perfusion in open arch surgery

Background

This study aimed to evaluate whether the use of mild hypothermic circulatory arrest (HCA) with selective cerebral perfusion (SCP) in open arch procedure provides comparable perioperative results to moderate HCA for patients with dissected or degenerative arch pathologies.

Methods

Between January 2017 and September 2020, a total of 88 consecutive patients (mean age 47±11 years, 71 males) underwent open arch repair under a single surgeon at our institution with mild or moderate systemic hypothermia assisted by unilateral or bilateral SCP. Patients were divided into groups according to the nasopharyngeal temperature at the beginning of HCA: a moderate HCA group (n=47, 53.4%) and a mild HCA group (n=41, 46.6%). The postoperative mortality, morbidity, and visceral organ functions between these groups were analyzed retrospectively.

Results

Compared to the moderate HCA group, the mild HCA group had a significantly higher core temperature (nasopharynx: 24.4±0.8 vs. 28.5±2, P<0.001; bladder 25.9±0.9 vs. 30±1.2, P<0.001), and the incidence of major adverse events (MAE) in this group was markedly lower (21.3% vs. 4.9%, P=0.031). No differences were identified between the two groups refer to in-hospital mortality, permanent neurological deficit (PND), temporary neurological deficit (TND), and paraplegia (8.5% vs. 2.4%, P=0.366; 8.5% vs. 0, P=0.120; 6.4% vs. 7.3%, P=1.0; 4.3% vs. 2.4%, P=1.0, respectively). In the moderate HCA group, 6 patients (12.8%) developed acute renal failure needing replacement therapy, which did not occur in the mild HCA group (P=0.028). The duration of ventilator support and intensive care unit stay was shorter in the mild HCA group, as well as a decreased volume of drainage during the first 24 h and reduced platelet transfusion.

Conclusions

The preliminary results of the mild HCA group with SCP applied in open arch repair, mainly in total arch replacement (TAR) and stented elephant trunk (SET) implantation for aortic dissection, were satisfactory. Furthermore, comparable inferior outcomes were obtained with mild HCA compared with that of the conventional moderate HCA strategy. These encouraging surgical and postoperative results favor this more aggressive hypothermia strategy in open arch repair.

[Predictors of early adverse events after the frozen elephant trunk procedure]

AIM

The aim of this study was to identify predictors of adverse events after the frozen elephant trunk procedure in the early postoperative period.

PATIENTS AND METHODS

Between March 2012 and March 2020, a total of 273 patients were operated on for aortic pathology. A retrospective analysis aimed at identifying probable predictors was performed on 83 patients who underwent the FET procedure. Uni- and multivariate logistic regression was used to identify predictors of such adverse events as postoperative delirium, respiratory failure, acute kidney injury, and in-hospital mortality.

RESULTS

According to the findings of the optimal multivariate regression model, separate reimplantation of the supra-aortic branches was a significant predictor of postoperative delirium (OR 10.41; 95% CI 1.1-35.45; p=0.05); significant risk factors for prolonged respiratory support were the duration of surgery (OR 1.02; 95% CI 1.01-1.03; p<0.001) and postoperative acute renal injury (OR 8.72; 95% CI 1.67-57.38; p=0.014). Independent risk factors for postoperative renal injury turned out to be the true lumen diameter of the descending aorta (OR 1.3; 95% CI 1.1-1.72; p=0.015) and chronic type A aortic dissection (OR 44.07; 95% CI 3.29-2354.8; p=0.014); statistically significant risk factors for in-hospital mortality were multiple organ dysfunction syndrome (OR 14.34; 95% CI 1.69-155.48; p=0.016) and coronary artery stenosis (OR 3.36; 95% CI 1.19-13.26; p=0.042).

CONCLUSION

Separate reimplantation of the supra-aortic branches, duration of surgery, acute kidney injury, chronic aortic dissection, multiple organ dysfunction syndrome, true lumen diameter of the descending aorta, coronary atherosclerosis and haemoglobin level were statistically significant predictors of adverse events in the early postoperative period.

Brain Protection in Aortic Arch Surgery: An Evolving Field

Despite advances in cardiac surgery and anesthesia, the rates of brain injury remain high in aortic arch surgery requiring circulatory arrest. The mechanisms of brain injury, including permanent and temporary neurologic dysfunction, are multifactorial, but intraoperative brain ischemia is likely a major contributor. Maintaining optimal cerebral perfusion during cardiopulmonary bypass and circulatory arrest is the key component of intraoperative management for aortic arch surgery. Various brain monitoring modalities provide different information to improve cerebral protection. Electroencephalography gives crucial data to ensure minimal cerebral metabolism during deep hypothermic circulatory arrest, transcranial Doppler directly measures cerebral arterial blood flow, and near-infrared spectroscopy monitors regional cerebral oxygen saturation. Various brain protection techniques, including hypothermia, cerebral perfusion, pharmacologic protection, and blood gas management, have been used during interruption of systemic circulation, but the optimal strategy remains elusive. Although deep hypothermic circulatory arrest and retrograde cerebral perfusion have their merits, there have been increasing reports about the use of antegrade cerebral perfusion, obviating the need for deep hypothermia. With controversy and variability of surgical practices, moderate hypothermia, when combined with unilateral antegrade cerebral perfusion, is considered safe for brain protection in aortic arch surgery performed with circulatory arrest. The neurologic outcomes of brain protection in aortic arch surgery largely depend on the following three major components: cerebral temperature, circulatory arrest time, and cerebral perfusion during circulatory arrest. The optimal brain protection strategy should be individualized based on comprehensive monitoring and stems from well-executed techniques that balance the major components contributing to brain injury.

Applicability of the Zenith Inner Branched Arch Endograft

Purpose: To evaluate the clinical and anatomical features of patients with arch pathology to better understand the applicability of the Zenith inner branched arch endograft (IBAE). Materials and Methods: A retrospective review was performed of 60 consecutive patients (mean age 62.5 years; 42 men) who presented with nonruptured aortic arch pathology at a single institution between 2009 and 2016. Patients were stratified into standard (no previous cardiac surgery, <80 years old, and no significant medical comorbidity), high (previous cardiac surgery or significant comorbidity), or prohibitive risk (turned down for operative intervention) for operative intervention. Anatomical measurements of the aorta were obtained on computed tomography scans; anatomical suitability was based on the device's instructions for use. Results: Overall, 27 (45%) patients had anatomy amenable to treatment with the existing IBAE. Inadequate proximal seal length and large ascending aortic diameters were the primary reasons for anatomical unsuitability. Shortening the inner curve seal zone from 25 to 15 mm and increasing the proximal seal zone diameter from 38 to 42 mm increased anatomical suitability to include 49 (82%) patients. Of these, 31 were in the high-risk cohort and 7 were deemed prohibitive risk; therefore, IBAE would have been strongly considered in these 38 patients. Conclusion: Based on anatomical criteria alone, nearly half of patients with aortic arch pathology have anatomy suitable to the Zenith IBAE in its current design. Arch branch vessel anatomy was not a limitation of the device. From a clinical standpoint, if endovascular repair were reserved for those at high or prohibitive risk for open repair, approximately 30% of patients would likely benefit from the IBAE in its current form.

Endovascular Repair of Aortic Arch Aneurysm with Surgeon-Modified Fenestrated Stent Graft

The authors describe a technique of treating patients with aortic arch aneurysm using surgeon-modified fenestrated stent graft (SMFSG). The technique is demonstrated in a 80-year-old patient whose aneurysm was successfully excluded with a SMFSG using Cook Alpha thoracic stent graft. The device was deployed, removed from its delivery system, and a fenestration created before being mounted back on the delivery system and constrained. It was transitioned through a series of sheaths before being introduced into its original sheath. The device was implanted via a common femoral artery access site; fenestration cannulated from the left brachial artery and bridged with a stent graft.

Single-center experience with an inner branched arch endograft

OBJECTIVE

Whereas open repair is the "gold standard" for most aortic arch diseases, a subgroup of patients might benefit from an endovascular approach. The introduction of branched stent grafts with dedicated design to address the challenges of the ascending aorta and the aortic arch has opened an entirely new area of treatment for these patients. We investigated the early outcomes of branched thoracic endovascular aortic repair (b-TEVAR) in various types of disease of the aortic arch.

METHODS

A retrospective analysis was conducted of prospectively collected data from a single center of all consecutive patients treated with b-TEVAR. The indication for elective endovascular repair was consented in an interdisciplinary case conference. All patients were treated with a custom-made inner branched arch endograft with two internal branches (Cook Medical, Bloomington, Ind) and left-sided carotid-subclavian bypass. Study end points were technical success, 30-day mortality, and complications as well as late complications and reinterventions.

RESULTS

Between 2012 and 2017, there were 54 patients (38 male; median age, 71 years) treated with diseases of the aortic arch. Indications for therapy involved degenerative aortic arch or proximal descending aortic aneurysms requiring arch repair (n = 24), dissection with or without false lumen aneurysms (n = 26), and penetrating aortic ulcers (n = 4). Forty-three cases (80%) were performed electively and 11 urgently for contained ruptures (n = 3) or symptomatic aneurysms (n = 8) with endografts already available for the patient or with grafts of other patients with similar anatomy. Technical success was achieved in 53 cases (98%). The 30-day mortality and major stroke incidence were 5.5% (3/54) and 5.5% (3/54), respectively; in-hospital mortality was 7.4% (n = 4), and minor strokes (including asymptomatic new cerebral lesions) occurred in 5.5% (n = 3). There were two cases of transient spinal cord ischemia with complete recovery and one of paraplegia. No retrograde type A dissections or cardiac injuries were observed. Three early stent graft-related reinterventions were necessary to correct proximal endograft kinking with type IA endoleak in one patient, a bridging stent graft stenosis in another patient, and false lumen persistent perfusion from dissected supra-aortic vessels in the last patient. Mean in-hospital stay was 14 ± 8 days. During a mean follow-up of 12 ± 9 months, three nonaorta-related deaths and one aorta-related death distal to the arch repair were observed.

CONCLUSIONS

Treatment of aortic arch diseases with b-TEVAR is feasible and safe with acceptable mortality and stroke rates.

Fenestrated Thoracic Endovascular Aortic Repair Using Physician-Modified Stent Grafts (PMSGs) in Zone 0 and Zone 1 for Aortic Arch Diseases

PURPOSE

To evaluate the outcomes of fenestrated thoracic endovascular aortic repair (f-TEVAR) using physician-modified stent grafts (PMSGs) in zone 0 and zone 1 for aortic arch diseases.

METHODS

f-TEVAR using PMSGs in Z0 and Z1 was performed on ten high-risk patients for open surgery from November 2015 to September 2017. Indications were complicated acute type B dissection (ABAD) with retrograde dissection involving the mid-arch (n = 1), distal arch aneurysms (n = 3), mid-arch aneurysms of the inner arch curvature (n = 3) and penetrating aortic ulcer located in the mid- or proximal arch (n = 3). Pre-, intra- and postoperative clinical data were recorded.

RESULTS

The median patient age was 61 (range 45-81) years, and 9 (90%) patients were men. Ten PMSGs (Medtronic Valiant stent grafts, n = 1; Relay thoracic stent grafts, n = 4; Cook TX2 device, n = 5) were deployed. PMSGs were deployed from Z0 and Z1 in 5 and 5 patients, respectively. Double small fenestrations for the left subclavian artery (LSA) and the left common carotid artery (LCCA), respectively, were created in 3 patients. Triple small fenestrations for the innominate artery (IA), the LCCA and the LSA, respectively, were created in 2 patients. One large fenestration for both the IA and the LCCA combined with one small fenestration for the LSA was created in 3 patients. One large fenestration for the LCCA combined with one small fenestration for the LSA was created in 2 patients. Posterior diameter-reducing ties were added to all the devices except to one Valiant stent graft. All but 2 patients underwent elective procedure. Median duration for stent graft modifications was 105 (range 90-125) min. The technical success rate was 90%. Overall mortality was 10% (1/10). One patient died of sudden cardiac arrest intraoperatively after the deployment of the PMSG and all the supra-aortic branch stents. Mean operative time was 106.0 ± 43.0 min, and fluoroscopy time was 30.6 ± 22.9 min. There were no type I or type III endoleaks, perioperative neurological complications or spinal cord ischemia. Median length of stay was 8 (range 4-35) days. Nine patients survived at mean 13.3 (range 6.0-19.0) months follow-up. Retrograde dissection occurred in one patient of Z0 group 40 days post-f-TEVAR and resolved after open repair. During follow-up, all target vessels remained patent without fenestration-related type I or III endoleaks.

CONCLUSIONS

f-TEVAR using PMSGs in Z0 and Z1 for the treatment of aortic arch diseases in high-risk patients is feasible in the hands of experienced operators.

Fenestrated Endovascular Repair of Zones 1 and 2 Aortic Arch Pathologies

BACKGROUND

Surgical management of aortic arch pathologies is complex, and endovascular developments have now enabled total or hybrid endovascular aortic arch repair. We present our early experience with fenestrated aortic arch repairs in Ishimaru zones 1 and 2 pathologies.

METHODS

In a single tertiary institution, all consecutive endovascular aortic arch repairs were reviewed. A preoperative computed tomography aortogram was performed to assess anatomic suitability, which we defined as having a proximal sealing zone with a maximum diameter of 38 mm and minimum length of 20 mm, absence of significant aortic tortuosity, and suitable sealing zones in target vessels.

RESULTS

From September 2015 to February 2018, 5 cases of fenestrated aortic arch endovascular repairs were performed. There were 3 male patients. The patients were between 57 and 83 years old, all of whom were American Society of Anesthesiologists (ASA) class II or III. Indications for surgery included aortic arch aneurysms (n = 3), a symptomatic aortic dissection, and a left subclavian artery aneurysm. Three patients had a scallop to the innominate artery, and one patient had a scallop to the left common carotid artery. Fenestrations were made to 3 left common carotid arteries and 3 left subclavian arteries. In 2 patients, a left carotid-subclavian bypass was performed, and the left subclavian artery origin occluded with a vascular plug. Technical success was 100%. One patient developed a right occipital infarct and acute myocardial infarction. The mean duration of surgery was 164 min, and the mean length of stay was 4.2 days. The mean follow-up period was 14.4 months.

CONCLUSIONS

The use of fenestrated grafts in the aortic arch is a feasible treatment option. However, certain limitations still exist, and preoperative planning is important in ensuring clinical success. Although this procedure appears feasible in the short term, long-term results and durability remain to be seen.

Simple retrograde cerebral perfusion is as good as complex antegrade cerebral perfusion for hemiarch replacement

Cerebral complication is a major concern after aortic arch surgery, which may lead to death. Thus, cerebral protection strategy plays the key role to obtain respectable results in aortic arch repair. Deep hypothermic circulatory arrest was introduced in 1970s to decrease the ischemic insults to the brain. However, safe duration of circulatory arrest time was limited to 30 minutes. The 1990s was the decade of evolution for cerebral protection, in which two adjuncts for deep hypothermic circulatory arrest were introduced: retrograde and antegrade cerebral perfusion (ACP) techniques. These two cerebral perfusion techniques significantly decreased incidence of postoperative neurological dysfunction and mortality after aortic arch surgery. Although there are no large prospective studies that demonstrate which perfusion technique provide better outcomes, multiple retrospective studies implicate that ACP may decrease cerebral complications compared to retrograde cerebral perfusion (RCP) when a long circulatory arrest time is required during aortic arch reconstructions. To date, many surgeons favor ACP over RCP during a complex aortic arch repair, such as total arch replacement and hybrid arch replacement. However, the question is whether the use of ACP is necessary during a short, limited circulatory arrest time, such as hemiarch replacement? There is a paucity of data that proves the advantages of a complex ACP over a simple RCP for a short circulatory arrest time. RCP with deep hypothermic circulatory arrest is the simple, efficient cerebral protection technique with minimal interference to the surgical field-and it potentially allows to flush atheromatous debris out from the arch vessels. Thus, it is the preferred adjunct to deep hypothermic circulatory arrest during hemiarch replacement in our institution.

Retrograde perfusion through superior vena cava reaches the brain during circulatory arrest

Background

The optimal technique for brain perfusion during circulatory arrest remains controversial. Concern exists that retrograde cerebral perfusion (RCP) via the superior vena cava (SVC) is unable to perfuse the brain. We evaluated whether RCP blood circulates through the brain parenchyma in humans during deep hypothermic circulatory arrest (DHCA). We hypothesized that a significant difference in the levels of S-100β (a protein with very high neuro-sensitivity) between the blood infused in the SVC and the effluent blood returning in the left carotid artery (CA) during RCP, should be regarded as a sign of the circulation of RCP blood through the brain parenchyma.

Methods

We enrolled 10 non-consecutive patients undergoing elective arch-surgery using DHCA and RCP. Circulating S-100β levels were measured at baseline and immediately before DHCA. During DHCA and RCP the difference in S-100β between the SVC and the CA was evaluated after 10 minutes of arrest and immediately before resumption of the circulation. S-100β levels were evaluated using enzyme-linked immunosorbent assay (ELISA).

Results

Mean DHCA duration was 22.4±7.9 minutes. Mean S-100β level at baseline was 92.5±54.9 µg/L. After 10 minutes of DHCA the level of S-100β in the CA was significantly higher than in the SVC (936.9±326.3 vs. 810.9±307.4 µg/L, P=0.0021). This difference was enhanced at the second DHCA sample (1113.8±334.2 vs. 920.5±340.0 µg/L, P=0.0002). There was a statistically significant correlation between the duration of DHCA and the percent difference in S-100β level between the SVC and the CA (Pearson's correlation coefficient =0.902).

Conclusions

RCP is able to perfuse the brain parenchyma in humans during DHCA.

Predictors of Outcomes after Correction of Acute Type A Aortic Dissection under Moderate Hypothermic Circulatory Arrest and Antegrade Cerebral Perfusion

INTRODUCTION

Hypothermic circulatory arrest is widely used for correction of acute type A aortic dissection pathology. We present our experience of 45 consecutive patients operated in our unit with bilateral antegrade cerebral perfusion and moderate hypothermic circulatory arrest.

METHODS

Between January 2011 and April 2015, 45 consecutive patients were admitted for acute type A aortic dissection and operated emergently under moderate hypothermic circulatory arrest and bilateral antegrade cerebral perfusion.

RESULTS

Mean age was 58±11.4 years old. Median circulatory arrest time was 41.5 (30-54) minutes while the 30-day mortality and postoperative permanent neurological deficits rates were 6.7% and 13.3%, respectively. Unadjusted analysis revealed that the factors associated with 30-day mortality were: preoperative hemodynamic instability (OR: 14.8, 95% CI: 2.41, 90.6, P=0.004); and postoperative requirement for open sternum management (OR: 5.0, 95% CI: 1.041, 24.02, P=0.044) while preoperative hemodynamic instability (OR: 8.8, 95% CI: 1.41, 54.9, P=0.02) and postoperative sepsis or multiple organ dysfunction (OR: 13.6, 95% CI: 2.1, 89.9, P=0.007) were correlated with neurological dysfunction. By multivariable logistic regression analysis, postoperative sepsis and multiple organ dysfunction independently predicted (OR: 15.9, 95% CI: 1.05, 96.4, P=0.045) the incidence of severe postoperative neurological complication. During median follow-up of 6 (2-12) months, the survival rate was 86.7%.

CONCLUSION

Bilateral antegrade cerebral perfusion and direct carotid perfusion for cardiopulmonary bypass, in the surgical treatment for correction of acute aortic dissection type A, is a valuable technique with low 30-day mortality rate. However, postoperative severe neurological dysfunctions remain an issue that warrants further research.

Brain protection in aortic arch aneurysm: antegrade or retrograde?

During open aortic arch repair, there is an interruption of cerebral perfusion and to prevent neurological sequelae, the hypothermic circulatory arrest has been established to provide sufficient brain protection coupled with adjuncts including retrograde and antegrade cerebral perfusion. To date, brain protection during open aortic arch repair is a contested topic as to which provides superior brain protection with little evidence existing to suggest supremacy of one modality over the other. This article reviews current literature reflecting on key and emerging studies in brain protection and their associated outcomes in patients undergoing open aortic arch surgery.

The Risk of Neurological Dysfunctions after Deep Hypothermic Circulatory Arrest with Retrograde Cerebral Perfusion

OBJECTIVE

Retrograde cerebral perfusion (RCP) is a brain protection technique that is adopted generally for anticipated short periods of deep hypothermic circulatory arrest (DHCA). However, the real impact of this technique on cerebral protection during DHCA remains a controversial issue.

METHODS

For 344 (59.5%) of 578 consecutive patients (mean age, 66.9 ± 10.9 years) who underwent cardiovascular surgery under DHCA at the present authors' institution (1999-2015), RCP was the sole technique of cerebral protection that was adopted in addition to deep hypothermia. Surgery of the thoracic aorta was performed in 95.9% of these RCP patients; in 92 cases there was an aortic arch involvement. Outcomes were reviewed retrospectively. The focus was on postoperative neurological dysfunctions.

RESULTS

There were 33 (9.6%) in-hospital deaths. Thirty-one (9%) patients had permanent neurological dysfunctions and 66 (19.1%) transitory neurological dysfunctions alone. Age older than 74 years (odds ratio [OR], 1.88, P = .023), surgery for acute aortic dissection (OR, 2.57; P = .0009), and DHCA time longer than 25 minutes (OR, 2.44; P = .0021) were predictors of neurological dysfunctions. The 10-year nonparametric estimate of freedom from all-cause death was 61.8% (95% confidence interval, 57.8%-65.8%). Permanent postoperative neurological dysfunctions were risk factors for cardiac or cerebrovascular death (hazard ratio, 2.6; P = .039) even after an adjusted survival analysis (P < .04).

CONCLUSIONS

According to the study findings, RCP, in addition to deep hypothermia, combines with a low risk of neurological dysfunctions provided that DHCA length is 25 minutes or less. Permanent postoperative neurological dysfunctions are predictors of poor late survival.

Retrograde Flushing of Living Donor Renal Allografts via the Renal Vein: A Simple, Effective Technique

BACKGROUND

Prograde flushing (PF) of living donor renal allografts with preservation solution via the renal artery or arteries is standard practice. PF may be difficult and potentially injurious to the donor kidney, especially in grafts with small or multiple arteries. In this report, we present our experience with retrograde flushing (RF) of 7 living donor kidneys via the renal vein.

METHODS

Retrospective review of 7 consecutive living donor renal transplants performed using the RF technique was performed. The 7 preceding living donor renal transplants performed using the standard arterial PF technique served as a control group.

RESULTS

All 7 recipients of RF kidneys experienced immediate graft function. At postoperative days 3 and 30, there was no difference in estimated glomerular filtration rate between the RF study group and PF controls.

CONCLUSIONS

The RF technique is simple and safe, with results equivalent to the PF technique. The RF technique may be especially useful after recovering kidneys with small and/or multiple arteries.

Intraoperative care for aortic surgery using circulatory arrest

The total circulatory arrest (CA) is necessary to achieve optimal surgical conditions in certain aortic pathologies, especially in those affecting the ascending aorta and aortic arch. During this procedure it is necessary to protect all the organs of ischemia, especially those of the central nervous system and for this purpose several strategies have been developed. The first and most important protective method is systemic hypothermia. The degree of hypothermia and the route of application have been evolving and currently tend to use moderate hypothermia (MH) (20.1-28 °C) associated with unilateral or bilateral selective cerebral perfusion methods. In this way the neurological results are better, the interval of security is greater and the times of extracorporeal circulation are smaller. Even so, it is necessary to take into account that there is the possibility of ischemia in the lower part of the body, especially of the abdominal viscera and the spinal cord, therefore the time of circulatory stop should be limited and not to exceed 80 minutes. Evidence of possible neurological drug protection is very weak and only mannitol, magnesium, and statins can produce some benefit. Inhalational anesthetics and some intravenous seem to have advantages, but more studies would be needed to test their long-term benefit. Other important parameters to be monitored during these procedures are blood glucose, anemia and coagulation disorders and acid-base balance. The recommended monitoring is common in complex cardiovascular procedures and it is of special importance the neurological monitoring that can be performed with several techniques, although currently the most used are Bispectral Index (BIS) and Near-Infrared Spectroscopy (NIRS). It is also essential to monitor the temperature routinely at the nasopharyngeal and bladder level and it is important to control coagulation with rotational thromboelastometry (ROTEM).

Temperature Management for Aortic Arch Surgery

Surgical treatment of aortic arch disease is a technically challenging procedure that requires complex circulation management strategies involving the use of hypothermic circulatory arrest. The definition of hypothermia has evolved with comfort and surgical adjuncts. This review describes the various circulation and temperature management strategies used during hemiarch and total arch replacement.

Optimal temperature management in aortic arch operations

Hypothermic circulatory arrest is a critical component of aortic arch procedures, without which these operations could not be safely performed. Despite the use of hypothermia as a protective adjunct for organ preservation, aortic arch surgery remains complex and is associated with numerous complications despite years of surgical advancement. Deep hypothermic circulatory arrest affords the surgeon a safe period of time to perform the arch reconstruction, but this interruption of perfusion comes at a high clinical cost: stroke, paraplegia, and organ dysfunction are all potential-associated complications. Retrograde cerebral perfusion was subsequently developed as a technique to improve upon the rates of neurologic dysfunction, but was done with only modest success. Selective antegrade cerebral perfusion, on the other hand, has consistently been shown to be an effective form of cerebral protection over deep hypothermia alone, even during extended periods of circulatory arrest. A primary disadvantage of using deep hypothermic circulatory arrest is the prolonged bypass times required for cooling and rewarming which adds significantly to the morbidity associated with these procedures, especially coagulopathic bleeding and organ dysfunction. In an effort to mitigate this problem, the degree of hypothermia at the time of the initial circulatory arrest has more recently been reduced in multiple centers across the globe. This technique of moderate hypothermic circulatory arrest in combination with adjunctive brain perfusion techniques has been shown to be safe when performing aortic arch operations. In this review, we will discuss the evolution of these protection strategies as well as their relative strengths and weaknesses.

Antegrade or Retrograde Cerebral Perfusion in Ascending Aorta and Hemiarch Surgery? A Propensity-Matched Analysis

BACKGROUND

Over the years, numerous options have been proposed for surgical management of ascending aorta and aortic arch pathology in an attempt to minimize postoperative morbidity and probability of death. We present a propensity score-matching analysis of 259 patients from a single unit who were operated on under deep hypothermic arrest with retrograde cerebral perfusion (DHCA/RCP) or moderate hypothermic circulatory arrest with selective antegrade cerebral perfusion (via common carotid artery) (MHCA/ACP).

METHODS

Between 2006 and 2014 a total of 259 consecutive patients underwent ascending aorta and hemiarch correction under HCA. DHCA/RCP and MHCA/ACP were performed on 207 and 52 patients, respectively. Baseline patient characteristics accounted for in the propensity matching were age, sex, acute aortic dissection, emergency operation, re-operation, preoperative hemodynamic instability, preoperative kidney injury, and CA time. After propensity scoring 40 pairs (80 patients) were successfully matched (p = 0.732). Outcomes were defined as the incidence of postoperative neurologic complications, 30-day mortality, and all-cause midterm mortality.

RESULTS

Surgical procedure that involved the MHCA/ACP technique was associated with 76.5% decreased risk (risk ratio, 0.235; 95% CI, 0.079 to 0.699) of postoperative neurologic complications (p = 0.009). In addition to MHCA/ACP in surgical procedure for acute aortic dissection a relevant trend was established for 30-day mortality (risk ratio, 0.333; 95% CI, 0.09 to 1.23). For midterm all-cause mortality, MHCA/ACP modestly decreased the number of deaths (p = 0.0456) in comparison with the DHCA/RCP technique.

CONCLUSIONS

MHCA/ACP in aortic arch surgical procedure is associated with a decreased risk of all types of neurologic complications and a trend toward decreased 30-day and midterm mortality in comparison with DHCA/RCP.