Moderate hypothermia at warmer temperatures is safe in elective proximal and total arch surgery: Results in 665 patients

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.

Clinical outcomes of mild versus moderate hypothermic circulatory arrest with antegrade cerebral perfusion in adult aortic arch surgery: A systematic review and meta-analysis

OBJECTIVES

In adult aortic arch surgery, moderate hypothermic circulatory arrest (HCA) with selective antegrade cerebral perfusion (SACP) (MoHACP) is widely used, but the application of mild HCA with SACP (MiHACP) is still controversial. This meta-analysis aimed to compare clinical outcomes using MiHACP or MoHACP.

METHODS

Studies comparing outcomes of MiHACP or MoHACP in adult aortic arch surgery were searched from four databases from inception through April 2022. Primary outcomes were postoperative permanent neurological deficit (PND), temporary neurological deficit (TND), and mortality. Secondary outcomes included other common complications. Meta-analysis was conducted using a random-effects model in all cases.

RESULTS

Eleven comparative studies were included, with 1555 patients in MiHACP group and 1499 patients in MoHACP group, and the mean HCA temperature were 29.4°C and 24.8°C, respectively. Postoperative PND, TND, mortality, paraplegia, dialysis, tracheotomy, reexploration for bleeding, and chest tube drainage volume were comparable in the two groups (p > 0.05). Ventilator time, intensive care unit and in-hospital length of stay were shorter in MiHACP group (p < 0.05). Outcomes were also comparable or had some benefits in MiHACP group when subgroup analyses were conducted according to hemiarch or total arch replacement, unilateral or bilateral SACP, HCA time, emergency aortic dissection surgery, and concomitant procedure.

CONCLUSION

The present meta-analysis showed acceptability of MiHACP in adult aortic arch surgery. Results need to be taken with caution as moderate risk of bias and very low quality of evidence were observed in this meta-analysis. Randomized controlled trials are needed for further analysis.

Unplanned readmissions, community socioeconomic factors, and their effects on long-term survival after complex thoracic aortic surgery

OBJECTIVE

We evaluated community socioeconomic factors in patients who had unplanned readmission after undergoing proximal aortic surgery (ascending aorta, aortic root, or arch).

METHODS

Unplanned readmissions for any reason within 60 days of the index procedure were reviewed by race, acuity at presentation, and gender. We also evaluated 3 community socioeconomic factors: poverty, household income, and education. Kaplan-Meier survival curves were used to assess long-term survival differences by group (race, acuity, and gender).

RESULTS

Among 2339 patients who underwent proximal aortic surgery during the 20-year study period and were discharged alive, our team identified 146 (6.2%) unplanned readmissions. Compared with White patients, Black patients lived in areas characterized by more widespread poverty (20.8% vs 11.1%; P = .0003), lower income ($42,776 vs $65,193; P = .0007), and fewer residents with a high school diploma (73.7% vs 90.1%; P < .0001). Compared with patients whose index operation was elective, patients who had urgent or emergency index procedures lived in areas with lower income ($54,425 vs $64,846; P = .01) and fewer residents with a high school diploma (81.1% vs 89.2%; P = .005). Community socioeconomic factors did not differ by gender. Four- and 6-year survival estimates were 63.1% and 63.1% for Black patients versus 89.1% and 83.0% for White patients (P = .0009). No significant differences by acuity or gender were found.

CONCLUSIONS

Among readmitted patients, Black patients and patients who had emergency surgery had less favorable community socioeconomic factors and poorer long-term survival. Earlier and more frequent follow-up in these patients should be considered. Developing off-campus clinics and specific postdischarge measures targeting these patients is important.

Racial disparities in thoracic aortic surgery: Myth or reality?

OBJECTIVE

We examined the relationship between Black or White race and adverse outcomes in patients who underwent surgery of the ascending aorta, aortic root, or aortic arch at our center.

METHODS

We analyzed 2335 consecutive patients who identified as Black (n = 217, 9.3%) or White (n = 2118, 90.7%) and underwent proximal aortic surgery. Patient zip codes were used to determine community socioeconomic (CSE) characteristics. The composite adverse outcome comprised mortality, persistent neurologic injury, and renal failure necessitating dialysis at discharge. We performed multivariable analysis, Kaplan-Meier analysis, and propensity score matching adjusted for CSE factors.

RESULTS

Median follow-up time was 3.7 years. Compared with White patients, Black patients lived in areas characterized by a higher percentage living below poverty level, lower income, and lower education level (P < .0001). Black patients had higher rates of emergency presentation (P < .0001) and lower 5- and 10-year survival rates (P = .0002). Short-term outcomes were similar between groups, except for respiratory failure and length of stay (P < .0001), which were higher in the Black population. After propensity score matching adjusted for CSE factors, Black and White patients (n = 204 each) had similar short-term outcomes and 5- and 10-year survival rates (P = .30). Multivariable analysis stratified by race showed that CSE factors independently predicted adverse outcomes in Black but not White patients.

CONCLUSIONS

This is among few studies that have analyzed the relationship between race and proximal aortic surgery. Although outcomes were similar between Black and White patients in our cohort after adjusting for CSE factors, unfavorable CSE factors predicted adverse outcomes in Black but not White patients. More patient-specific studies are needed.

Early outcome of simplified total arch reconstruction under mild hypothermia (30-32 °C) with distal aortic perfusion

OBJECTIVE

We designed a simplified total arch reconstruction (s-TAR) technique which could be performed under mild hypothermia (30-32 °C) with distal aortic perfusion. This study aimed to compare its efficacy of organ protection with the conventional total arch reconstruction (c-TAR).

METHODS

We reviewed the clinical data of 195 patients who had ascending aortic aneurysm with extended aortic arch dilation and underwent simultaneous ascending aorta replacement and TAR procedure between January 2018 and December 2022 in our center. 105 received c-TAR under moderate hypothermia (25-28 °C) with circulatory arrest (c-TAR group); rest 90 received s-TAR under mild hypothermia (30-32 °C) with distal aortic perfusion (s-TAR group).

RESULTS

The s-TAR group demonstrated shorter CPB time, cross-clamp time and lower body circulatory arrest time compared with the c-TAR group. The 30-day mortality was 2.9% for the c-TAR group and 1.1% for the s-TAR group (P = 0.043). The mean duration of mechanical ventilation was shorter in the s-TAR group. Paraplegia was observed in 4 of 105 patients (3.8%) in the c-TAR group, while no such events were observed in the s-TAR group. The incidence of temporary neurologic dysfunction was significantly higher in the c-TAR group. The incidence of permanent neurologic dysfunction also showed a tendency to be higher in the c-TAR group, without statistical significance. Furthermore, the incidence of reoperation for bleeding were significantly lower in the s-TAR group. The rate of postoperative hepatic dysfunction and all grades of AKI was remarkably lower in the s-TAR group. The 3-year survival rate was 95.6% in the s-TAR group and 91.4% in the c-TAR group.

CONCLUSIONS

s-TAR under mild hypothermia (30-32℃) with distal aortic perfusion is associated with lower mortality and morbidity, offering better neurological and visceral organ protection compared with c-TAR.

Reoperative total arch replacement after previous cardiovascular surgery: Outcomes in 426 consecutive patients

OBJECTIVE

Total aortic arch replacement (TAR) after previous cardiovascular surgery is technically challenging and is becoming more frequent as outcomes for primary arch repair have improved. primary. We analyzed outcomes of reoperative compared with first-time TAR.

METHODS

The institutional aortic database was queried to identify consecutive patients undergoing TAR between 1997 and 2022. In total, 426 patients underwent TAR, of whom 150 (35%) had previous cardiovascular surgery (reop TAR) and 276 (65%) underwent their first cardiovascular operation.

RESULTS

The reop TAR group was younger (61 ± 13 vs 71 ± 11, P < .001) with more comorbidities such as ischemic heart disease (12% vs 4.3%, P = .006), previous stroke (36% vs 14.5%, P < .001), and renal impairment (24% vs 12.7%, P = .004). Reop TAR had longer cardiac ischemic times (119.3 ± 45.5 minutes vs 98 ± 31.9 minutes, P < .001), a greater operative mortality (3.3% vs 0.4%, P = .040), and incurred a 4-fold increased risk of major adverse event (95% confidence interval [CI], 1.41-11.49, P = .009). Ten-year survival was also lower in the reop TAR cohort (76% vs 82.2%; hazard ratio, 1.79; 95% CI, 1.12-2.86, P = .015) and there was greater need for late reinterventions, mainly on the downstream aorta (hazard ratio, 1.29; 95% CI, 1.03-1.62, P = .024).

CONCLUSIONS

Reop TAR is a technically challenging operation and is associated with increased operative mortality and adverse events. Gratifying results can be obtained with meticulous surgical planning and focused attention on end-organ protection. Late reinterventions occur in a significantly greater percentage of patients undergoing reop TAR, and future studies should focus attention on identifying those at-risk groups who may benefit from a more aggressive index procedure.

Training in Aortic Arch Surgery as a Blueprint for a Structured Educational Team Approach: A Review

Background and objectives: The treatment of pathologies of the aortic arch is a complex field of cardiovascular surgery that has witnessed enormous progress recently. Such treatment is mainly performed in high-volume centres, and surgeons gain great experience in mastering potential difficulties even under emergency circumstances, thereby ensuring the effective therapy of more complex pathologies with lower complication rates. As the numbers of patients rise, so does the need for well-trained surgeons in aortic arch surgery. But how is it possible to learn surgical procedures in a responsible way that, in addition to surgical techniques, also places particular demands on the overall surgical management such as perfusion strategy and neuro-protection? This is why a good training programme teaching young surgeons without increasing the risk for patients is indispensable. Our intention was to highlight the most challenging aspects of aortic arch surgery teaching and how young surgeons can master them. Materials and Methods: We analysed the literature to find out which methods are most suitable for such teaching goals and what result they reveal when serving as teaching procedures. Results: Several studies were found comparing the surgical outcome of young trainees with that of specialists. It was found that the results were comparable whether the procedure was performed by a specialist or by a trainee assisted by the specialist. Conclusions: We thus came to the conclusion that even for such a complex type of intervention, the responsible training of young surgeons by experienced specialists is possible. However, it requires a clear strategy and team approach to ensure a safe outcome for the patient.

Duration of deep hypothermic circulatory arrest for aortic arch surgery: is it a myth, fiction, or scientific leap?

INTRODUCTION

The use of deep hypothermic circulatory arrest (DHCA) to provide aortic surgeons with a bloodless operative field while simultaneously protecting the brain and peripheries from ischemic damage revolutionized cardiac and aortic surgery, and is currently used in specialist centers across the globe. However, it is associated with manifold adverse outcomes, including neurocognitive dysfunction and mortality. This review seeks to analyze the relationship between DHCA duration and clinical outcome, and evaluate the controversies and limitations surrounding its use.

EVIDENCE ACQUISITION

We performed a review of available literature with statistical analysis to evaluate the relationship between DHCA duration (<40 min and >40 min) and key clinical outcomes, including mortality, permanent and temporary neurological deficit, renal damage, admission length, and reintervention rate. The controversies surrounding DHCA use and future directions for care are also explored.

EVIDENCE SYNTHESIS

Statistical analysis revealed no significant association (P>0.05) between DHCA duration and clinical outcomes (early and late mortality rates, neurological deficit, admission length, and reintervention rate), both with and without adjunctive perfusion techniques.

CONCLUSIONS

Available literature suggests that the relationships between DHCA duration (with and without adjunctive perfusion) and clinical outcomes are unclear, and at present not statistically significant. Alternative surgical and endovascular techniques have been identified as promising novel approaches not requiring DHCA, as have the use of biomarkers to enable early diagnosis and intervention for aortic pathologies.

Endovascular repair of the ascending aorta: the last frontier

Different pathologies of the ascending aorta (AA), including aneurysms, acute and chronic dissections, and pseudoaneurysms, have been treated with open surgical repair with very good results, especially at aortic centers of excellence. There is, however, a subset of patients for whom open surgery is considered to pose high or prohibitive risk. These patients can benefit from a less invasive approach with catheters and wires, percutaneous techniques and stent grafts. However, the existing technology was developed to treat descending thoracic aortic pathologies; it is not approved for use in the AA by the US Food and Drug Administration (FDA). The devices used for the descending thoracic aorta (DTA) have certain size and design limitations that make their application to the AA cumbersome at times. As a result, custom-made endografts have been used to treat pathologies in the AA, although their use is feasible only in elective procedures. In addition, the AA has specific anatomic and physiologic characteristics that raise concerns about the long-term durability of the current technology. In this review, we outline the limitations, challenges and current status of endovascular technology to treat pathologies of the AA.

Reoperative Aortic Arch Surgery under Mild Systemic Hypothermia: Two-Center Experience

BACKGROUND

 The aim of the study was to assess the indications, surgical strategies, and outcomes after reoperative aortic arch surgery performed generally under mild hypothermia.

METHODS

 Ninety consecutive patients (60 males, mean age, 55 ± 16 years) underwent open reoperative aortic arch surgery after previous cardiac aortic surgery. The indications included chronic-progressive arch aneurysm (55.5%), chronic aortic dissection (17.8%), contained arch rupture (16.7%), and graft infection (10%). The reoperation was performed through a repeat sternotomy (96%) or clamshell thoracotomy (4%) using antegrade cerebral perfusion under mild systemic hypothermia (28.9 ± 2.5°C) in all except three patients.

RESULTS

 The surgery comprised hemiarch or total arch replacement in 41 (46%) and 49 (54%) patients, respectively. The distal extension included classic or frozen elephant trunk technique, each in 12 patients, and total descending aorta replacement in 4 patients. Operative mortality was 6 (6.7%) among all patients, with age identified as the only independent predictor of operative mortality (p = 0.05). Permanent and transient neurologic deficits occurred in 1% and 9% of the patients, respectively. Estimated survival at 8 years was 59 ± 8% with advanced heart failure predictive for late mortality (p = 0.014). Freedom from second reoperation or intervention on the aorta was 78 ± 6% at 8 years, with most of these events occurring downstream in patients with chronic degenerative aneurysms.

CONCLUSION

 Aortic arch reoperations performed using antegrade cerebral perfusion under mild systemic hypothermia offer favorable operative outcomes with an exceptionally low rate of neurologic morbidity without any difference between hemiarch and complex arch procedures.

Early and long-term results of hypothermic circulatory arrest in aortic surgery: a 20-year single-centre experience

AIMS

The aim of this study was to document the postoperative outcomes of patients who underwent hypothermic circulatory arrest (HCA), the evolution of HCA management over time and to identify the risks factor for early mortality and postoperative stroke.

METHODS

Four hundred and twenty-four patients who underwent aortic surgery with HCA at our institution between January 1995 and June 2016 were consecutively included.

RESULTS

The main indications were degenerative aneurysm (254; 59.9%) and acute type A aortic dissection (146; 34.4%). Interventions were performed under deep (18.4 ± 0.9°C; n = 350; 82.5%) or moderate (23.9 ± 1.9°C; n = 74; 17.5%) hypothermia. Antegrade cerebral perfusion (ACP) was employed in 86 (20.3%) cases. The use of moderate hypothermia significantly increased from 2011, to become the preferred strategy in 2016. The in-hospital mortality was 12.5% and the postoperative stroke rate was 7.1%. Kaplan--Meier 5-year survival was 65.7%. Nonelective timing [odds ratio (OR) 4.05; P < 0.001], stroke (OR 3.77' P = 0.032), renal failure (OR 2.49; P = 0.023), redo surgery (2.42; P = 0.049) and CPB time (OR 1.05; P = 0.03) were independent risk factors for in-hospital mortality in multivariate analysis. Femoral cannulation was the only independent risk factor for stroke (OR 3.97; P = 0.002). The level of hypothermia and the use of ACP were not associated with either in-hospital mortality or postoperative stroke.

CONCLUSION

HCA might be widely considered to achieve a radical treatment of the aortic disease, provided that hypothermia is maintained below the 24°C safety threshold and ACP is used for HCA exceeding 30 min, to ensure optimal brain, spinal cord and visceral organs protection.

Cardiopulmonary bypass duration is an independent predictor of adverse outcome in surgical repair for acute type A aortic dissection

OBJECTIVE

This study aimed to investigate the relationship between the duration of cardiopulmonary bypass (CPB) and stroke or early death in patients with acute type A aortic dissection (ATAAD) receiving total aortic arch replacement with the frozen elephant trunk procedure (TAR with FET).

METHODS

A retrospective cohort study of 258 consecutive patients was conducted at Beijing Anzhen Hospital from December 2014 to June 2016. Patients who received TAR with FET for ATAAD were included. An adverse outcome (AO) was defined as 30-day mortality or stroke. Additionally, an AO was compared using propensity score matching.

RESULTS

The incidence of AO was 13.6% (n = 35). The 30-day mortality rate was 10.8% and the stroke rate was 9.3%. Patients were aged 47.9 ± 10.6 years old. The duration of CPB was an independent predictor of occurrence of AO after adjusting for confounding factors by multivariable logistic regression analysis (odds ratio 1.101, 95% confidence interval 1.003-1.208). In matched analysis, CPB duration remained a risk factor of AO.

CONCLUSIONS

The duration of CPB is an independent predictor of AO in surgical repair for ATAAD. The underlying mechanisms of this association are important for developing improved prevention strategies.

Renal protective effect of the aortic balloon occlusion technique in total arch replacement with frozen elephant trunk

Background

Organ dysfunction caused by hypothermic circulatory arrest continues to concern surgeons. The aortic balloon occlusion (ABO) technique can significantly shorten the circulatory arrest time in total arch replacement with frozen elephant trunk (TAR with FET). This study aims to analyze the renal protective effect of the ABO technique and to analyze the predictors of acute kidney injury (AKI) and continuous renal replacement therapy (CRRT) after TAR with FET.

Methods

Between August 2017 and September 2018, 247 patients who underwent TAR with FET were divided into ABO and moderate hypothermic circulatory arrest (MHCA) groups. The primary endpoint was postoperative AKI defined by the Kidney Disease Improving Global Outcomes (KDIGO) criteria. Multivariable logistic analysis was used to identify the predictors of AKI and CRRT after TAR with FET.

Results

With the application of the ABO technique, the circulatory arrest time was significantly shortened (ABO 4, IQR: 3-6 vs. MHCA 18, IQR: 16-20, P<0.001). Meanwhile, surgeons safely set the lowest nasopharyngeal temperature at a higher grade (ABO 28.1, IQR: 27.4-28.5 vs. MHCA 24.7, IQR: 24.1-25.1, P<0.001). The peak serum creatinine (SCr) values within 48 hours after the surgery was lower in the ABO group than in the MHCA group (ABO 124, IQR: 97-173 vs. MHCA 146, IQR: 108-221, P=0.008). The distribution of AKI grade according to the KDIGO criteria differed between the two groups (P=0.04): more patients in the ABO group were free from AKI (Grade 0) than patients in the MHCA group (33% vs. 23.1%), and the proportion of patients with high-grade AKI (Grades 2 and 3) in the ABO group was lower than that in the MHCA group (21% vs. 32%). The ABO technique was associated with reduced potential for AKI, but was not protective for CRRT.

Conclusions

The ABO technique significantly shortened the circulatory arrest time and safely elevated temperature, and provided better renal protection in patients undergoing TAR with FET. The ABO technique did not reverse the need for CRRT, nor did it reduce mortality or major adverse events.

The use of cIMT as a predictor of postoperative stroke in patients undergoing surgical repair of acute type a aortic dissection

BACKGROUND

Acute type A aortic dissection (ATAAD) is a life-threatening condition that requires surgical intervention. Stroke remains an extremely serious adverse outcome that can occur in ATAAD patients undergoing aortic arch repair, leading to higher rates of patient mortality and decreased postoperative quality of life. In the present study, we sought to determine whether carotid intima-media thickness (cIMT) is a reliable predictor of postoperative stroke risk.

MATERIALS AND METHODS

This was a prospective study of 76 patients with ATAAD undergoing aortic arch repair. For all patients, cIMT was determined preoperatively through a Doppler-based method. Incidence of different forms of neurological dysfunction, including temporary neurological dysfunction (TND) and stroke, was monitored in these patients, and the relationship between cIMT and stroke incidence was assessed using a receiver-operating characteristic (ROC) curve. Prognostic variables associated with stroke risk were further identified through univariate and multivariate analyses.

RESULTS

A total of 26/76 (34.2%) patients in the present study suffered from neurological dysfunction, of whom 16 (21.0%) suffered from TND and 10 (13.2%) suffered a stroke. The remaining 50 patients (65.8%) did not suffer from neurological dysfunction. The cIMT values in the stroke, TND, and neurological dysfunction-free patients in this study were 1.12 ± 0.19 (mm), 0.99 ± 0.13 (mm), and 0.87 ± 0.13 (mm), respectively. A total of 4 patients in this cohort died during the study, including 1 in the TND group and 3 in the stroke group. An ROC curve analysis indicated that cIMT could predict stroke with an area under the curve value of 0.844 (95% CI, 0.719-0.969; p < 0.001). A multivariate analysis revealed that cIMT > 0.9 mm was independently associated with stroke risk (p = 0.018).

CONCLUSION

We found that cIMT can be used to predict postoperative stroke risk in ATAAD patients undergoing aortic arch repair, with a cIMT > 0.9 mm coinciding with increased stroke risk in these patients.

TRIAL REGISTRATION

ChiCTR1900022289. Date of registration 4 April 2019 retrospectively registered.

Safety of Hypothermic Circulatory Arrest During Unilateral Antegrade Cerebral Perfusion for Aortic Arch Surgery

BACKGROUND

Hypothermic circulatory arrest (HCA) with adjunctive unilateral antegrade cerebral perfusion (UACP) is widely used as a cerebral protection strategy during aortic arch surgery. However, the ideal temperature for HCA during UACP remains unknown. The study compared clinical outcomes of patients in different temperature groups for HCA during UACP.

METHODS

From January 2009 to January 2016, 1691 patients who underwent aortic arch surgery for HCA during UACP in Beijing Anzhen Hospital were categorized into 2 groups according to nasopharyngeal temperature before initiating systemic circulatory arrest: the low temperature group (≤ 24°C, 22.9°C; 22.0°C-23.5°C; n = 1207) and the high temperature group (24.1°C-28.0°C, 24.6°C; 24.3°C-24.9°C; n = 484). After balancing the differences of baseline conditions by propensity score matching, 473 pairs of patients were matched, and the prognosis was compared with matched patients.

RESULTS

The multivariable Cox regression analysis shows the high temperature group was an independent predictor for 30-day mortality (hazard ratio [HR], 0.55; 95% confidence interval [CI], 0.33-0.93; P = 0.03). After matching, the high temperature group was still an independent predictor of 30-day mortality (HR, 0.55; 95% CI, 0.32-0.98; P = 0.04). In subgroup analyses, there was an interaction between the high temperature group and UACP > 40 minutes for 30-day mortality (P_{for interaction}< 0.05). The high temperature group had a significant protective effect in the UACP ≤ 40 minutes subgroup (HR, 0.30; 95% CI, 0.12-0.74; P = 0.01) but not in the UACP > 40 minutes subgroup (HR, 1.00; 95% CI, 0.46-2.20; P = 0.99).

CONCLUSIONS

This study shows that the high temperature (24.1°C-28.0°C) management strategy for HCA during UACP is safer for UACP ≤ 40 minutes. High temperature benefits were not found in patients for UACP > 40 minutes.

Endovascular Repair of Ascending Aortic Pathologies With Tubular Endografts: A Single-Center Experience

Purpose: To investigate the endovascular treatment of ascending aortic pathologies of high-risk patients unsuitable for open repair. Materials and Methods: From 2010 to 2017, 24 patients (mean age 70±15 years, range 29-90; 18 men) were treated at a single center for various pathologies of the ascending aorta, including acute or chronic type A aortic dissections (n=16), pseudoaneurysms (n=6), fixation of a dislocated percutaneous aortic valve (n=2), and miscellaneous indications (n=3). The patients were selected following an interdisciplinary case evaluation, attended by cardiologists and cardiac and vascular surgeons. The Zenith Ascend TAA Endovascular Graft was implanted; simultaneous procedures were performed in 13 patients. Of the total 27 Ascend TEVAR procedures (24 primary and 3 reinterventions), 17 were performed urgently and 10 electively. The primary outcome measure was 30-day survival. The secondary outcomes were cardiovascular complications, midterm survival, and reintervention rate. Results: Clinical success was achieved in all but 1 case. The 30-day survival was 79% (19/24); of the 5 deaths only 1 was directly related to the endograft implanted. In the 30-day postoperative period, there was 1 myocardial infarction, 2 major strokes, a mycotic pseudoaneurysm, a case of Ascend TEVAR-induced high-grade aortic insufficiency, and a minor stroke; 1 patient developed paraplegia after concurrent implantation of a 4-branched abdominal stent-graft. Two patients had a reintervention within 30 days for the pseudoaneurysm and the aortic insufficiency, respectively. During a mean follow-up of 11 months (0-35 months), there was 1 late death (cancer) and 1 additional reintervention at 10 months for a late type Ia endoleak (12.5% reintervention rate). Conclusion: Endovascular repair of ascending aortic pathologies with stent-grafts is a feasible treatment option with acceptable early and midterm outcomes in high-risk patients unsuitable for open surgery. The complexity of Ascend TEVAR might justify higher reintervention rates.

Temperature Selection in Antegrade Cerebral Perfusion for Aortic Arch Surgery: A Meta-Analysis

BACKGROUND

The increasing use of antegrade cerebral perfusion (ACP) during aortic arch surgery has corresponded with a trend toward warmer target temperatures for hypothermic circulatory arrest. This meta-analysis examined the clinical outcomes using colder or warmer circulatory arrest targets with ACP.

METHODS

Electronic searches were performed using four databases from their inception to February 2017. Comparative studies of adult patients who underwent aortic arch operations using ACP at different circulatory arrest temperatures were included. Data were extracted by 2 independent researchers and analyzed according to predefined end points using a random-effects model.

RESULTS

The literature search identified 18 comparative studies, with 1,215 patients in the "cold" cohort and 1,417 in the "warm" cohort. Mean hypothermic circulatory arrest temperatures were 20.3°C and 26.5°C in the cold and warm groups, respectively. A trend existed for increased permanent neurologic deficit overall when colder targets were used (odds ratio, 1.45; 95% confidence interval, 0.98 to 2.13; p = 0.06); this became significant when adjusted estimates were aggregated (odds ratio, 1.65; 95% confidence interval, 1.06 to 2.55; p = 0.03). No difference in the mortality rate was seen when adjusted effects were aggregated. Temporary neurologic deficit, postoperative dialysis, ventilator time, and intensive care unit stay were significantly reduced in the warm cohort overall. No significant differences in reexploration for bleeding were found.

CONCLUSIONS

ACP with warmer circulatory arrest temperatures may reduce the incidence of permanent neurologic deficit as well as potentially other clinical outcomes. Further studies are required to determine the safe circulatory arrest durations for visceral organs at warmer temperatures.

Neuro-protection in open arch surgery

Although antegrade cerebral perfusion (ACP) is the predominant method of protecting the brain in patients undergoing total arch replacement, both deep hypothermic circulatory arrest and ACP provide excellent and comparable clinical outcomes with regard to mortality, stroke, and temporary neurological deficit rates.