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

2024 EACTS/EACTAIC/EBCP Guidelines on cardiopulmonary bypass in adult cardiac surgery

Clinical practice guidelines consolidate and evaluate all pertinent evidence on a specific topic available at the time of their formulation. The goal is to assist physicians in determining the most effective management strategies for patients with a particular condition. These guidelines assess the impact on patient outcomes and weigh the risk-benefit ratio of various diagnostic or therapeutic approaches. While not a replacement for textbooks, they provide supplementary information on topics relevant to current clinical practice and become an essential tool to support the decisions made by specialists in daily practice. Nonetheless, it is crucial to understand that these recommendations are intended to guide, not dictate, clinical practice, and should be adapted to each patient's unique needs. Clinical situations vary, presenting a diverse array of variables and circumstances. Thus, the guidelines are meant to inform, not replace, the clinical judgement of healthcare professionals, grounded in their professional knowledge, experience and comprehension of each patient's specific context. Moreover, these guidelines are not considered legally binding; the legal duties of healthcare professionals are defined by prevailing laws and regulations, and adherence to these guidelines does not modify such responsibilities. The European Association for Cardio-Thoracic Surgery (EACTS), the European Association of Cardiothoracic Anaesthesiology and Intensive Care (EACTAIC) and the European Board of Cardiovascular Perfusion (EBCP) constituted a task force of professionals specializing in cardiopulmonary bypass (CPB) management. To ensure transparency and integrity, all task force members involved in the development and review of these guidelines submitted conflict of interest declarations, which were compiled into a single document available on the EACTS website (https://www.eacts.org/resources/clinical-guidelines). Any alterations to these declarations during the development process were promptly reported to the EACTS, EACTAIC and EBCP. Funding for this task force was provided exclusively by the EACTS, EACTAIC and EBCP, without involvement from the healthcare industry or other entities. Following this collaborative endeavour, the governing bodies of EACTS, EACTAIC and EBCP oversaw the formulation, refinement, and endorsement of these extensively revised guidelines. An external panel of experts thoroughly reviewed the initial draft, and their input guided subsequent amendments. After this detailed revision process, the final document was ratified by all task force experts and the leadership of the EACTS, EACTAIC and EBCP, enabling its publication in the European Journal of Cardio-Thoracic Surgery, the British Journal of Anaesthesia and Interdisciplinary CardioVascular and Thoracic Surgery. Endorsed by the EACTS, EACTAIC and EBCP, these guidelines represent the official standpoint on this subject. They demonstrate a dedication to continual enhancement, with routine updates planned to ensure that the guidelines remain current and valuable in the ever-progressing arena of clinical practice.

A comprehensive organ protection strategy in total arch replacement: a propensity-weighted analysis

OBJECTIVES

The goal was to report the outcomes and determine the effectiveness of a comprehensive organ protection strategy in total arch replacement.

METHODS

A total of 350 patients who underwent total arch replacement were enrolled. Fifty-four patients underwent the comprehensive organ protection strategy with bilateral antegrade cerebral perfusion and the aortic balloon occlusion technique (comprehensive strategy group); 296 patients underwent the standard strategy with unilateral antegrade cerebral perfusion (standard strategy group). Inverse probability of treatment weighting was used to balance the baseline characteristics.

RESULTS

After inverse probability of treatment weighting, the comprehensive strategy group had lower incidences of 30-day mortality (0.9% vs 4.9%, P = 0.002), continuous renal replacement therapy (0.6% vs 10.3%, P < 0.001), renal failure (4.6% vs 13.7%, P < 0.001), hepatic dysfunction (11.6% vs 21.1%, P = 0.001) and shorter duration of mechanical ventilation [16 (13, 31) vs 20 (14, 48) h, P = 0.011]. Multivariable logistic analysis showed that the comprehensive strategy was an independent protective factor of 30-day mortality [odds ratio (OR): 0.242, 95% confidence interval (CI): 0.068-0.867, P = 0.029], continuous renal replacement therapy (OR: 0.045, 95% CI: 0.008-0.264, P = 0.001), renal failure (OR: 0.351, 95% CI: 0.156-0.788, P = 0.011) and mechanical ventilation >20 h (OR: 0.531, 95% CI: 0.319-0.883, P = 0.015). Kaplan-Meier analysis showed that mid-term survival was comparable.

CONCLUSIONS

The comprehensive organ protection strategy might improve early survival, reduce the use of continuous renal replacement therapy, have protective effects on the kidney and shorten mechanical ventilation time in total arch replacement. This strategy might be considered a viable alternative in total arch replacement.

Cerebral Protection Strategies in Aortic Arch Surgery-Past Developments, Current Evidence, and Future Innovation

Surgery of the aortic arch remains a complex procedure, with neurological events such as stroke remaining its most dreaded complications. Changes in surgical technique and the continuous innovation in neuroprotective strategies have led to a significant decrease in cerebral and spinal events. Different modes of cerebral perfusion, varying grades of hypothermia, and a number of pharmacological strategies all aim to reduce hypoxic and ischemic cerebral injury, yet there is no evidence indicating the clear superiority of one method over another. While surgical results continue to improve, novel hybrid and interventional techniques are just entering the stage and the question of optimal neuroprotection remains up to date. Within this perspective statement, we want to shed light on the current evidence and controversies of cerebral protection in aortic arch surgery, as well as what is on the horizon in this fast-evolving field. We further present our institutional approach as a large tertiary aortic reference center.

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.

Multiple Cardiac Diseases Involving the Aortic Arch: Beating Heart Debranching, and Normothermic Arch Replacement: A Case Series

(1) Background: Conventional open surgery is still the gold standard for aortic arch disease, and despite recent developments in optimizing strategies for neuroprotection, distal organ perfusion, and myocardial protection, aortic arch replacement is still associated with high morbidity and mortality rates. (2) Methods: We present our case series of 12 patients undergoing surgical management of multiple cardiac diseases involving the aortic arch. In this single-center study, we report our initial experience over a five-year period (from December 2018 to October 2023) with the use of a "debranching first" technique for the supra-aortic vessels of a beating heart, followed by the cardiac step addressing proximal diseases, and a final distal step treating the aortic arch. This strategy aims to minimize cardiac, cerebral, and peripheral ischemia. (3) Results: Six patients underwent aortic root replacement with either Bentall (n = 4) or valve-sparing aortic root (David procedure) (n = 2). The mean nasopharyngeal temperature was 34 °C and the mean cardiocirculatory arrest was 14.3 min. The early mortality was 8.3% (1 patient); no patient experienced a permanent neurologic event. (4) Conclusions: In patients with complex aortic disease and concomitant cardiac disease, this approach reduces the need for hypothermia and decreases cardiopulmonary bypass time and myocardial arrest time and therefore could represent a valid surgical option, even in high-risk patients.

2022 ACC/AHA guideline for the diagnosis and management of aortic disease: A report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

Cardiopulmonary bypass for total aortic arch replacement surgery: A review of three techniques

One treatment for acute type A aortic dissection is to replace the ascending aorta and aortic arch with a graft during circulatory arrest of the lower body, but this is associated with high mortality and morbidity. Maintaining the balance between oxygen supply and demand during circulatory arrest is the key to reducing morbidity and is the primary challenge during body perfusion. The aim of this review is to summarize current knowledge of body perfusion techniques and to predict future development of this field. We present three perfusion techniques based on deep hypothermic circulatory arrest (DHCA): DHCA alone, DHCA with selective cerebral perfusion, and DHCA with total body perfusion. DHCA was first developed to provide a clear surgical field, but it may contribute to stroke in 4%–15% of patients. Antegrade or retrograde cerebral perfusion can provide blood flow for the brain during circulatory arrest, and it is associated with much lower stroke incidence of 3%–9%. Antegrade cerebral perfusion may be better than retrograde perfusion during longer arrest. In theory, blood flow can be provided to all vital organs through total body perfusion, which can be implemented via either arterial or venous systems, or by combining retrograde inferior vena caval perfusion with antegrade cerebral perfusion. However, whether total body perfusion is better than other techniques require further investigation in large, multicenter studies. Current techniques for perfusion during circulatory arrest remain imperfect, and a technique that effectively perfuses the upper and lower body effectively during circulatory arrest is missing. Total body perfusion should be systematically compared against selective cerebral perfusion for improving outcomes after circulatory arrest.

Systematic review and network meta-analysis of various nadir temperature strategies for hypothermic circulatory arrest for aortic arch surgery

BACKGROUND

The optimal nadir temperature for hypothermic circulatory arrest during aortic arch surgery remains unclear. We aimed to assess and compare clinical outcomes of all three temperature strategies (deep, moderate, and mild hypothermia) using a network meta-analysis.

METHODS

After literature search with MEDLINE and EMBASE through December 2021, studies comparing clinical outcomes with deep (<20°C), moderate (20-28°C), or mild (>28°C) hypothermic circulatory arrest were included. The outcomes of interest were perioperative mortality, stroke, transient ischemia attack (TIA), acute kidney injury (AKI), postoperative bleeding, operative time, and length of hospital stay.

RESULTS

Twenty-four comparative studies were identified, including 6018 patients undergoing aortic arch surgery using hypothermic circulatory arrest (deep: 2,978, moderate: 2,525, and mild: 515). Compared to deep hypothermia, mild and moderate hypothermia were associated with lower mortality (mild vs. deep: odds ratio [OR] 0.50; 95% confidence interval (CI) 0.29-0.87, moderate vs. deep: OR 0.68; 95% CI 0.54-0.86). In addition, mild hypothermia was associated with lower stroke (OR 0.50; 95% CI 0.28-0.89), AKI (OR 0.36; 95% CI 0.15-0.88) and postoperative bleeding (OR 0.55; 95% CI 0.31-0.97) compared to deep hypothermia. There was no significant difference between mild and moderate hypothermia in mortality, AKI or bleeding occurrence, while mild hypothermia was associated with shorter operative time and hospital stay. There was no significant difference in TIA rate among three groups.

CONCLUSIONS

Mild hypothermia was associated with overall more favorable clinical outcomes with comparable neurological complications compared to deep hypothermia. Furthermore, considering the shorter operative time and hospital stay compared with moderate hypothermia, mild hypothermia may be warranted when appropriate adjunctive cerebral perfusion is employed.

Thoracic Aortic Aneurysm Surgery: DON'T QUIT-JUST DO IT

Surgical aortic repair has progressed from aneurysm ligation to homografts to Dacron grafts to totally endovascular interventions. These fields will continue to evolve, and new endovascular technology will be used in virtually every part of the aorta, eventually dominating this field of surgery. However, as surgeons, we must be cautious and not let go of our open-surgery skills, as they will always be the ultimate bailout solution.

2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate. Structure: Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

Optimal temperature management in aortic arch surgery: A systematic review and network meta-analysis

OBJECTIVES

New temperature management concepts of moderate and mild hypothermic circulatory arrest during aortic arch surgery have gained weight over profound cooling. Comparisons of all temperature levels have rarely been performed. We performed direct and indirect comparisons of deep hypothermic circulatory arrest (DHCA) (≤20°C), moderate hypothermic circulatory arrest (MHCA) (20.1-25°C), and mild hypothermic circulatory arrest (mild HCA) (≥25.1°C) in a network meta-analysis.

METHODS

The literature was systematically searched for all papers published through February 2022 reporting on clinical outcomes after aortic arch surgery utilizing DHCA, MHCA and mild HCA. The primary outcome was operative mortality. The secondary outcomes were postoperative stroke and acute kidney failure (AKI).

RESULTS

A total of 34 studies were included, with a total of 12,370 patients. DHCA was associated with significantly higher postoperative incidence of stroke when compared with MHCA (odds ratio [OR], 1.46, 95% confidence interval [CI], 1.19-1.78) and mild HCA: (OR, 1.50, 95% CI, 1.14-1.98). Furthermore, DHCA and MHCA were associated with higher operative mortality when compared with mild HCA (OR 1.71, 95% CI, 1.23-2.39 and OR 1.50, 95% CI, 1.12-2.00, respectively). Separate analysis of randomized and propensity score matched studies showed sustained increased risk of stroke with DHCA in contrast to MHCA and mild HCA (OR, 1.61, 95% CI, 1.18-2.20, p value = .0029 and OR, 1.74, 95% CI, 1.09-2.77, p value = .019).

CONCLUSIONS

In the included studies, the moderate to mild hypothermia strategies were associated with decreased operative mortality and the risk of postoperative stroke. Large-scale prospective studies are warranted to further explore appropriate temperature management for the treatment of aortic arch pathologies.

Optimal circulatory arrest temperature for aortic hemiarch replacement with antegrade brain perfusion

OBJECTIVE

This study sought to identify the optimal temperature for moderate hypothermic circulatory arrest in patients undergoing elective hemiarch replacement with antegrade brain perfusion.

METHODS

The Society of Thoracic Surgeons adult cardiac surgery database was queried for elective hemiarch replacements using antegrade brain perfusion for aneurysmal disease (2014-2019). Generalized estimating equations and restricted cubic splines were used to determine the risk-adjusted relationships between temperature as a continuous variable and outcomes.

RESULTS

Elective hemiarch replacement with antegrade brain perfusion occurred in 3898 patients at 374 centers with a median nadir temperature of 24.9 °C (first quartile, third quartile = 22.0 °C, 27.5 °C) and median circulatory arrest time of 19 minutes (first quartile, third quartile = 14.0 minutes, 27.0 minutes). After adjustment for comorbidities, circulatory arrest time, and individual surgeon, patients cooled between 25 and 28 °C had an early survival advantage compared with 24 °C, whereas those cooled between 21 and 23 °C had higher risks of mortality compared with 24 °C. A nadir temperature of 27 °C was associated with the lowest risk-adjusted odds of mortality (odds ratio, 0.62; 95% confidence interval, 0.42-0.91). A nadir temperature of 21 °C had the highest risk of mortality (odds ratio, 1.4; 95% confidence interval, 1.13-1.73). Risk of experiencing a major morbidity was elevated in patients cooled between 21 and 23 °C, with the highest risk occurring in patients cooled to 21 °C (odds ratio, 1.12; 95% confidence interval, 1.01-1.24).

CONCLUSIONS

For patients with aneurysmal disease undergoing elective hemiarch with antegrade brain perfusion, circulatory arrest with a nadir temperature of 27 °C confers the greatest early survival benefit and smallest risk of postoperative morbidity.

Effect of Deep Hypothermic Circulatory Arrest Versus Moderate Hypothermic Circulatory Arrest in Aortic Arch Surgery on Postoperative Renal Function: A Systematic Review and Meta-Analysis

Background

Moderate hypothermic circulatory arrest (MHCA) has been widely used in aortic arch surgery. However, the renal function after MHCA remains controversial. We performed a systematic review and meta‐analysis direct comparison of the postoperative renal function of MHCA versus deep hypothermic circulatory arrest (DHCA) in aortic arch surgery.

Methods and Results

We searched PubMed, Embase, and the Cochrane Library for postoperative renal function after aortic arch surgery with using MHCA and DHCA, published from inception to January 31, 2020. The primary outcome was renal failure. Secondary outcomes were the need for renal therapy and other major postoperative outcomes. The random‐effects model was used for all comparisons to pool the estimates. A total of 14 observational studies with 4142 patients were included. Compared with DHCA, MHCA significantly reduced the incidence of renal failure (odds ratio [OR], 0.76; 95% CI, 0.61–0.94; P=0.011; I²=0.0%) and the need of renal replacement (OR, 0.68; 95% CI, 0.48–0.97; P=0.034; I²=0.0%). Subgroup analysis showed that when the hypothermic circulatory arrest time was <30 minutes, the incidence of renal failure in MHCA group was significantly lower than that in DHCA group (OR, 0.73; 95% CI, 0.54–0.99; P=0.040; I²=1.1%), whereas an insignificant difference between 2 groups when hypothermic circulatory arrest time was >30 minutes (OR, 0.76; 95% CI, 0.51–1.13; P=0.169; I²=17.3%).

Conclusions

MHCA compared with DHCA reduces the incidence of renal failure and the need for renal replacement.

Registration

URL: https://www.crd.york.ac.uk/prospero; Unique identifier: CRD42020169348.