Impact of Cerebral Perfusion on Outcomes of Aortic Surgery: The Society of Thoracic Surgeons Adult Cardiac Surgery Database Analysis

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.

Safety of prolonged bilateral antegrade cerebral perfusion in aortic arch surgery with moderate hypothermia

OBJECTIVES

This study investigates the impact of bilateral antegrade cerebral perfusion (ACP) time on outcomes in aortic arch surgery.

METHODS

In total, 961 patients underwent either hemiarch (n = 385) or total arch replacement (n = 576) with bilateral ACP and moderate hypothermia management between 2006 and 2020 across 2 aortic centres. ACP time was categorized into 4 groups (≤30 min: n = 169, 30-60 min: n = 298, 60-90 min: n = 261, >90 min: n = 233). Inverse probability of treatment weighting yielded a well-balanced cohort among the 4 groups except for the cannulation site. Adjusted cubic spline and multivariable logistic analysis were performed, controlling for surgical procedure, cannulation site and cardiopulmonary bypass (CPB) time, to identify the relationship between ACP time and major in-hospital complications including mortality, stroke, acute renal failure and prolonged ventilation.

RESULTS

There remained a significant difference in surgical procedures and CPB time in the matched cohort. The incidences of mortality and stroke did not show significant trend (P = 0.052 and 0.717, respectively). Cubic spline curves showed that odds ratios did not increase linearly for any complications with increasing ACP time. Furthermore, ACP time, even exceeding 90 min, was not associated with complication rates [mortality: odds ratio = 1.459 (0.368-6.049), P = 0.595; stroke: 0.310 (0.058-1.635), P = 0.166; renal failure: 1.744 (0.521-6.094), P = 0.374; prolonged ventilation: 1.502 (0.535-4.286), P = 0.442], whereas CPB time was associated with mortality and prolonged ventilation.

CONCLUSIONS

Even when ACP time exceeded 90 min, it was not associated with major in-hospital complications, questioning its validity as a marker for surgical insult.

Moderate hypothermia circulatory arrest as a brain-protective strategy for type A aortic dissection

OBJECTIVES

Brain-protective strategies for acute type A aortic dissection (TAAD) remain controversial. Moderate hypothermia circulatory arrest (MHCA) without cerebral perfusion is not commonly used. However, we aimed to assess its safety and efficacy in 358 patients who underwent hemiarch replacement with MHCA for acute type A aortic dissection at our institution from August 2012 to August 2022.

METHODS

Clinical outcomes were compared according to circulatory arrest time [≤15 min (S group, n = 52) vs ≥16 min (L group, n = 306)]. The primary outcome was postoperative stroke.

RESULTS

The S group had more older patients (72.5 vs 68.8 years; P = 0.04), a greater incidence of carotid artery malperfusion (21% vs 11%; P = 0.043) and a lower body mass index (21.7 vs 23.6 kg/m2; P < 0.01) and hemodynamic instability (3.8% vs 16%; P = 0.02) than the L group. The incidence of postoperative stroke (7.7% vs 12%; P = 0.33) and the rate of 30-day mortality (5.8% vs 6.5%; P = 0.83) did not significantly differ between groups. After adjusting for all potential confounding factors pre- and intraoperatively, there was no significant difference in postoperative outcomes between groups.

CONCLUSIONS

MHCA alone for TAAD had comparable postoperative outcomes with circulatory arrest times under and over 15 min. However, longer arrest times were associated with a higher risk of stroke.

Recent trends of open surgery for acute type A aortic dissection in Japan

OBJECTIVE

Reporting clinical outcomes of acute type A aortic dissection.

METHODS

Data derived from the survey of the Japanese Association for Thoracic Surgery, the Japan Cardiovascular Database, and the Japanese Registry of All Cardiac and Vascular Diseases were analyzed.

RESULTS

Between 2012 and 2015, the Japanese Registry of All Cardiac and Vascular Diseases study collected 13,131 patients and the hospital mortality was 24.3%. The surgical mortality was significantly lower than medical one (11.8% vs 49.7%; p < 0.001). The Japanese Association for Thoracic Surgery survey disclosed the number of surgeries has been increased to 6157 in 2018 and the hospital death has decreased to 10.5%. The Japan Cardiovascular Database, collected 29,486 patients from 2013 to 2018. Age at surgery was 59.8  ±  14.2 years and patients younger than 65 years in 61% and 21% were older than 75 years. Ninety-four percent had surgery within 24 h after diagnosis. Antegrade cerebral perfusion was used in 74% and deep hypothermic circulatory arrest with/without retrograde cerebral perfusion in 26%. Replacement of the ascending aorta was performed in 62% and total arch replacement in 28%. The aortic valve was replaced in 7.9% and repaired in 4.4%. The hospital mortality was 11%. New stroke occurred in 12%, hemodialysis in 7.3%, paraplegia in 3.9%, and prolonged ventilation in 15%.

CONCLUSION

The number of operations for type A aortic dissection has increased, and hospital mortality has improved. Although the early results after surgery for type A aortic dissection are acceptable, new strategies to improve early outcomes in patients with preoperative comorbidities are required.

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.

Noteworthy in Cardiothoracic Surgery 2023

Noteworthy in Cardiothoracic Surgery 2023 summarizes a few of the most high-impact trials and provocative trends in cardiothoracic surgery and transplantation this past year. Transplantation using organs procured from donation after circulatory death (DCD) continues to increase, and the American Society of Transplant Surgeons released recommendations on best practices in 2023. We review a summary of data on the impact of DCD on heart and lung transplantation. There has been increased interest in extracorporeal life support (ECLS), particularly after the COVID-19 pandemic, and we review the results of the highly discussed ECLS-SHOCK trial, which randomized patients in cardiogenic shock with planned revascularization to ECLS vs usual care. With improving survival outcomes in complex aortic surgery, there is a need for higher-quality evidence to guide which cooling and cerebral perfusion strategies may optimize cognitive outcomes in these patients. We review the short-term outcomes of the GOT ICE trial (Cognitive Effects of Body Temperature During Hypothermic Circulatory Arrest), a multicenter, randomized controlled trial of three different nadir temperatures, evaluating outcomes in cognition and associated changes in functional magnetic resonance imaging. Finally, both the Society of Thoracic Surgeons (STS) and the American College of Cardiology, American Heart Association, American College of Chest Physicians and Heart Rhythm Society (ACC/AHA/ACCP/HRS) updated atrial fibrillation guidelines in 2023, and we review surgically relevant updates to the guidelines and the evidence behind them.

Cannula Placement for Cerebral Protection Without Circulatory Arrest in Patients Undergoing Hemiarch Aortic Aneurysm Repair

BACKGROUND

Aortic aneurysms involving the proximal aortic arch, which require hemiarch-type repair, typically require circulatory arrest with antegrade cerebral perfusion. Left carotid antegrade cerebral perfusion (LCP) via distal arch cannulation without circulatory arrest was used in this study's patient population. The goal was to assess the operative efficiency and clinical outcomes of using a distal arch cannulation technique that would not require any hypothermic circulatory arrest (HCA) time compared with more traditional brachiocephalic artery cannulation with right-sided unilateral antegrade cerebral perfusion (RCP) and HCA.

METHODS

A single-center retrospective review of patients with replacement of the distal ascending aorta involving the proximal arch was performed. Patients with an intramural hematoma or dissection were excluded. Between January 2015 and December 2019, 68 adult patients had undergone a hemiarch repair because of aneurysmal disease. Analysis of baseline demographics, operative data, and clinical outcomes was performed.

RESULTS

Comparing the 68 patients: 21 patients were treated with RCP (via brachiocephalic artery graft with HCA), and 47 patients were treated with LCP (via distal aortic arch cannulation with cross-clamp between the brachiocephalic and left common carotid arteries without HCA). Baseline characteristics and outcomes were evaluated for both groups. The LCP group was younger (LCP median [IQR] age, 60 [53-65] years vs RCP median [IQR] age, 67 [59-71] years]. Sex, race, body mass index, comorbidities, and ejection fraction were similar between the groups. Cardiopulmonary bypass time (LCP, 123 minutes vs RCP, 149 minutes) and unilateral cerebral perfusion time (LCP, 17 minutes vs RCP, 22 minutes) were longer in the RCP group. Bleeding, prolonged ventilatory support, kidney failure, and length of stay were similar. In-hospital mortality was 2% in the LCP group vs 0% in the RCP group. Stroke occurred in 2 patients (4.2%) in the LCP group and in 0% of the RCP group. Mortality at 6 months in the LCP and RCP groups was 3% and 10%, respectively.

CONCLUSION

Distal arch cannulation with LCP without HCA is a reasonable and safe alternative strategy for patients requiring hemiarch replacement for aneurysmal disease. This technique may provide additional benefits by avoiding circulatory arrest in these complex cases.

Prolonged Periods of Antegrade Cerebral Perfusion Are Safe During Elective Arch Surgery

BACKGROUND

Cerebral circulatory arrest times >40 minutes during aortic surgery have previously been shown to be associated with increased morbidity and mortality. The purpose of this study was to redefine what would constitute a safe period of circulatory arrest for patients who underwent elective proximal aortic operations requiring antegrade cerebral perfusion (ACP).

METHODS

The ARCH International aortic database was queried, and 2008 patients undergoing elective arch operations with circulatory arrest using ACP were identified. Circulatory arrest time was categorized a priori in 10-minute intervals. To further determine the impact of this variable on outcomes, hierarchical multivariable regression analysis was performed.

RESULTS

Unadjusted mortality increased with increasing circulatory arrest time from 4.8% (<40 minutes) to 13.5% (>90 minutes; P < .001), but risk of stroke was not impacted (P = .4). When treated as a continuous variable, mortality increased significantly with increasing circulatory arrest time, whereas the risk of permanent stroke did not. Using <40 minutes as the reference, multivariable analysis showed no statistical increase in mortality for ranges up to 80 minutes of circulatory arrest. The risk of permanent stroke was not significantly higher for any time interval >40 minutes up to 90 minutes.

CONCLUSIONS

In this series of patients who underwent elective proximal aortic surgery using ACP, periods of circulatory arrest up to at least 80 minutes were not associated with significant increases in mortality or permanent stroke. Modern perfusion strategies have allowed for increased safety during elective arch cases requiring prolonged periods of circulatory arrest.

Brain and lower body protection during aortic arch surgery

BACKGROUND

Deep hypothermic circulatory arrest (DHCA) at ≤20°C for aortic arch surgery has been widely used for decades, with or without cerebral perfusion (CP), antegrade (antegrade cerebral perfusion [ACP]), or retrograde. In recent years nadir temperature progressively increased to 26°C-28°C (moderately hypothermic circulatory arrest [MHCA]), adding ACP. Aim of this multicentric study is to evaluate early results of aortic arch surgery and if DHCA with 10 min of cold reperfusion at the same nadir temperature of the CA before rewarming (delayed rewarming [DR]) can provide a neuroprotection and a lower body protection similar to that provided by MHCA + ACP.

METHODS

A total of 210 patients were included in the study. DHCA + DR was used in 59 patients and MHCA + ACP in 151. Primary endpoints were death, neurologic event (NE), temporary (TNE), or permanent (permanent neurologic deficit [PND]), and need of renal replacement therapy (RRT).

RESULTS

Operative mortality occurred in 14 patients (6.7%), NEs in 17 (8.1%), and PNDs in 10 (4.8%). A total of 23 patients (10.9%) needed RRT. Death + PND occurred in 21 patients (10%) and composite endpoint in 35 (19.2%). Intergroup weighed logistic regression analysis showed similar prevalence of deaths, NDs, and death + PND, but need of RRT (odds ratio [OR]: 7.39, confidence interval [CI]: 1.37-79.1) and composite endpoint (OR: 8.97, CI: 1.95-35.3) were significantly lower in DHCA + DR group compared with MHCA + ACP group.

CONCLUSIONS

The results of our study demonstrate that DHCA + DR has the same prevalence of operative mortality, NE and association of death+PND than MHCA + ACP. However, the data suggests that DHCA + DR when compared with MHCA + ACP provides better renal protection and reduced prevalence of composite endpoint.

Deep Versus Moderate Hypothermia in Acute Type A Aortic Dissection: A Propensity-Matched Analysis

BACKGROUND

The ideal temperature for hypothermic circulatory arrest (HCA) during acute type A aortic dissection (ATAAD) repair has yet to be determined. We examined the clinical impact of different degrees of hypothermia during dissection repair.

METHODS

Out of 240 cases of ATAAD between June 2014 and December 2019, 228 patients were divided into two groups according to lowest intraoperative temperature: moderate hypothermic circulatory arrest (MHCA) (20-28°C) versus deep hypothermic circulatory arrest (DHCA) (<20°C). From this, 74 pairs of propensity-matched patients were analysed with respect to operative data and short-term clinical outcomes. Independent predictors of a composite outcome of 30-day mortality and stroke were identified.

RESULTS

Mean lowest temperature was 25.5±3.9°C in the MHCA group versus 16.0±2.9°C in DHCA. Overall 30-day mortality of matched cohort was 11.5% (17 deaths), there were no significant different between matched groups. Cardiopulmonary bypass (CPB) times were longer in DHCA (221.0±69.9 vs 190.7±74.5 mins, p=0.01). Antegrade cerebral perfusion (ACP) during HCA predicted a lower composite risk of 30-day mortality and stroke (OR 0.38). Female sex (OR 4.71), lower extremity ischaemia at presentation (OR 3.07), and CPB >235 minutes (OR 2.47), all portended worse postoperative outcomes.

CONCLUSIONS

A surgical strategy of MHCA is at least as safe as DHCA during repair of acute type A aortic dissection. ACP during HCA is associated with reduced 30-day mortality and stroke, whereas female sex, lower extremity ischaemia, and longer CPB times are all predictive of poorer short-term outcomes.

Elective aortic arch surgery: cerebral perfusion flows and transient neurological dysfunctions

AIMS

Selective antegrade cerebral perfusion technique is a method of cerebral protection used worldwide during aortic arch surgery. This study was designed to identify a potential correlation between perfusion flows and the development of postoperative transient neurological dysfunctions.

METHODS

From January 2015 to May 2020, 175 patients underwent elective surgical replacement of the aortic arch using selective antegrade cerebral perfusion at the Cardiac Surgery Unit of Sant'Orsola Hospital in Bologna. Considering that patients who developed a permanent neurological dysfunction and those who died before a possible evaluation of neurological status were excluded, the study population included 160 patients. The perfusion flows were collected and analyzed. Univariate and multivariate analyses were performed to identify the statistical risk factors involved in the onset of transient neurological dysfunctions.

RESULTS

The study population was divided into two groups: 138 patients (86.3%) without and 22 (13.8%) with postoperative transient neurological complications. Among the intra-operative parameters collected in the study, the univariate analysis showed that the indexed medium perfusion flow of selective antegrade cerebral perfusion was significantly lower in the transient neurological dysfunctions group (11.63 ± 2.41 ml/kg/min vs 12.62 ± 2.39 ml/kg/min, P -value = 0.03). The multivariate logistic regression analysis showed that the female gender ( P  = 0.004, OR = 4.816, IC = 1.636-14.174) was predictor of transient neurological dysfunctions.

CONCLUSION

The results of the study showed that lower perfusion flows seem to be related to a higher probability of developing transient neurological dysfunctions. However, the analysis of a wider population is required to confirm these preliminary data.

Cerebral protection using deep hypothermic circulatory arrest versus retrograde cerebral perfusion for aortic hemiarch reconstruction

BACKGROUND

With evolutions in technique, recent data encourage the use of cerebral perfusion during aortic arch repair. However, a randomized data have demonstrated higher rates of neurologic injury according to MRI lesions using antegrade cerebral perfusion during hemiarch reconstruction.

METHODS

This was a retrospective review of two institutional aortic center databases to identify adult patients who underwent aortic hemiarch reconstruction for elective aortic aneurysm or acute type A aortic dissection. Patients were stratified according to cerebral protection method: (1) deep hypothermic circulatory arrest (DHCA) group versus (2) DHCA/retrograde cerebral perfusion (RCP) group.

RESULTS

A total of 320 patients and 245 patients underwent hemiarch reconstruction for aortic aneurysm electively and aortic dissection, respectively. In aneurysmal pathology, the DHCA group included 133 patients and the DHCA/RCP group included 187 patients. Operative mortality was 0.8% in the DHCA group and 2.7% in the DHCA/RCP group (p = 0.41). Kaplan-Meier survival estimates revealed comparable 2-year survival (p = 0.14). In dissection, 43 patients and 202 patients were included in the DHCA group and the DHCA/RCP group, respectively. Operative mortality was equivalent between the two groups (11.6% in the DHCA group and 9.4% in the DHCA/RCP group, p = 0.58). Long-term survival was similar at 2 years between the groups (p = 0.06). Multivariable analysis showed cerebral perfusion strategy was not associated with the composite outcome of operative mortality and stroke.

CONCLUSIONS

In treating both elective and acute ascending aortic pathologies with hemiarch reconstruction, both DHCA alone or in combination with RCP yield comparable results.

Risk factors for impaired neurological outcome after thoracic aortic surgery

Background

We aimed to identify risk factors for an impaired postoperative neurological outcome after thoracic aortic surgery.

Methods

Data from all patients undergoing thoracic aortic surgery between 2010 and 2020 at our institution were collected and analyzed retrospectively. Logistic regression analysis was used to identify independent risk factors for permanent postoperative neurological deficit (ND) (stroke), which was defined as a ND lasting at least seven days.

Results

Thoracic aortic surgery was performed in 1,334 patients. Of these, 286 (21.4%) underwent emergency surgery. The mean EuroSCORE II was 8.6±10.1. A perioperative stroke occurred in 94 patients (7.0%). Of all strokes, 62.8% (n=59) were considered of embolic and 24.5% (n=23) of hemodynamic origin. In elective procedures, stroke rates ranged from 0.5% after valve-sparing root replacement to 8.1% after arch surgery. Adjusted logistic regression identified advanced age [>70 years; odds ratio (OR), 1.83; P=0.009], acute type A dissection (ATAD) (OR, 1.69; P=0.0495), aortic arch surgery (OR, 3.24; P<0.001), concomitant coronary artery bypass grafting (CABG) (OR, 2.19; P=0.005), and high extracorporeal circulation (ECC) time (>230 min; OR, 1.70; P=0.034) as independent risk factors for all strokes. Secondary endpoint analyses revealed that risk factors for hemodynamic stroke were arch surgery, advanced age (>70 years), atherosclerosis, and ATAD. Risk factors for embolic stroke were arch surgery, concomitant CABG and preoperative cerebral malperfusion.

Conclusions

Identified independent risk factors for all strokes were advanced age, ATAD, arch surgery, concomitant CABG, and high ECC time. Hemodynamic and embolic strokes show distinct risk profiles.

Optimal brain protection in aortic arch surgery

There is considerable debate with regard to the optimal cerebral protection strategy during aortic arch surgery. There are three contemporary techniques in use which include straight deep hypothermic circulatory arrest (DHCA), DHCA with retrograde cerebral perfusion (DHCA + RCP), and moderate hypothermic circulatory arrest with antegrade cerebral perfusion (MHCA + ACP). Appropriate application of these methods ensures appropriate cerebral, myocardial, and visceral protection. Each of these techniques has benefits and drawbacks and ensuring coordinated circulation management strategy is critical to safe performance of aortic arch surgery. In this report, we will review various cannulation strategies, review logistics of hypothermia, and review the relevant literature to outline the strengths and weaknesses of these various cerebral protection strategies.

Neuroprotective strategies with circulatory arrest in open aortic surgery - A meta-analysis

Objective

Deep hypothermic circulatory arrest (DHCA) in aortic surgery is associated with morbidity and mortality despite evolving strategies. With the advent of antegrade cerebral perfusion (ACP), moderate hypothermic circulatory arrest (MHCA) was reported to have better outcomes than DHCA. There is no standardised guideline or consensus regarding the hypothermic strategies to be employed in open aortic surgery. Meta-analysis was performed comparing DHCA with MHCA + ACP in patients having aortic surgery.

Methods

A systematic review of the literature was undertaken. Any studies with DHCA versus MHCA + ACP in aortic surgeries were selected according to specific inclusion criteria and analysed to generate summative data. Statistical analysis was performed using STATS Direct. The primary outcomes were hospital mortality and post-operative stroke. Secondary outcomes were cardiopulmonary bypass time (CPB), post-operative blood transfusion, length of ICU stay, respiratory complications, renal failure and length of hospital stay. Subgroup analysis of primary outcomes for Arch surgery alone was also performed.

Results

Fifteen studies were included with a total of 5869 patients. There was significantly reduced mortality (Pooled OR = +0.64, 95% CI = +0.49 to +0.83; p = 0.0006) and stroke rate (Pooled OR = +0.62, 95% CI = +0.49 to +0.79; p < 0.001) in the MHCA group. MHCA was associated significantly with shorter CPB times, shorter duration in ICU, less pulmonary complications, and reduced rates of sepsis. There was no statistical difference between the two groups in terms of circulatory arrest times, X-Clamp times, total operation duration, transfusion requirements, renal failure and post-op hospital stay.

Conclusion

MHCA + ACP are associated with significantly better post-operative outcomes compared with DHCA for both mortality and stroke and majority of the secondary outcomes.

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.

Transapical Antegrade Ascending Aorta Stent-Grafting: Going Through the Front Door

OBJECTIVE

Ascending aorta stent-grafting (AASG) is a new option that has shown initial promising results. In selected cases, when neither conventional surgery nor transfemoral retrograde approach are feasible, antegrade transapical (TA) access can be performed. The aim of this single-center retrospective study was to evaluate outcomes of patients undergoing AASG through a TA approach.

METHODS

We analyzed all patients undergoing AASG through a TA approach at our institution. Three different devices were used, including Relay Stent-Graft System (Terumo Aortic, UK), Gore Conformable Thoracic Aortic Graft (W. L. Gore & Associates, Inc., USA), and Valiant Thoracic Stent Graft (Medtronic, Ireland). All patients underwent clinical and computed tomographic angiogram (CTA) evaluation before hospital discharge.

RESULTS

From May 2010 to December 2019, 3 consecutive patients underwent AASG at our institution. Mean age was 69 years. Three different types of endografts were used in 1 patient each. All patients stayed in the intensive care unit for 24 hr and mean hospital stay was 12 days. We did not observe any major adverse event. One patient died of pneumonia 2 months after the procedure and the other 2 patients are alive and in good clinical conditions at a mean follow-up of 56 months. Predischarge CTA showed good anatomic results with no endoleaks in all cases.

CONCLUSIONS

This initial experience shows that AASG is feasible and provides encouraging clinical and anatomic results in selected high-risk patients.

Neurological Complications of Cardiac Procedures

Neurological complications after cardiac surgery and percutaneous cardiac interventions are not uncommon. These include periprocedural stroke, postoperative cognitive dysfunction after cardiac surgery, contrast-induced encephalopathy after percutaneous interventions, and seizures. In this article, we review the incidence, pathophysiology, diagnosis, and management of these complications. Improved understanding of these complications could lead to their prevention, faster detection, and facilitation of diagnostic workup and appropriate treatment.

STS Adult Cardiac Surgery Database: 2021 Update on Outcomes, Quality, and Research

The Society of Thoracic Surgeons Adult Cardiac Surgery Database is the most mature and comprehensive cardiac surgery database. It has been the foundation for quality measurement and improvement activities in cardiac surgery, facilitated the generation of accurate risk adjusted performance benchmarks and serves as a platform for novel research. Recent enhancements have added to the database's functionality, ease of use, and value to multiple stakeholders. This report is the sixth in a series of annual reports that provide updated volumes, outcomes, database-related developments, quality improvement initiatives, and research summaries using the Adult Cardiac Surgery Database in the past year.

Moderate Versus Deep Hypothermia in Type A Acute Aortic Dissection Repair: Insights from the International Registry of Acute Aortic Dissection

BACKGROUND

The optimal strategy for cerebral protection during repair of type A acute aortic dissection has yet to be determined. We sought to determine the impact of differing degrees of hypothermia in patients undergoing acute dissection repair.

METHODS

All patients in the International Registry of Acute Aortic Dissection Interventional Cohort database who underwent type A acute aortic dissection repair between 2010 and 2018 were identified. Data for operative temperature were available for 1962 patients subsequently divided into 2 groups according to lowest temperature: moderate hypothermic circulatory arrest (MHCA) (20-28°C) versus deep hypothermic circulatory arrest (DHCA) (<20°C). We then propensity matched 362 pairs of patients and analyzed operative data and short-term outcomes.

RESULTS

The median lowest temperature was 25.0°C in the matched MHCA group as compared with 18.0°C in the DHCA group. For the entire cohort of 1962 patients, in-hospital mortality was 14.2% (278 deaths) but was not significantly different between DHCA and MHCA. The perioperative stroke rate was comparable between groups, before and after propensity matching. Circulatory arrest times were significantly longer in the MHCA cohort, regardless of matching. Use of antegrade or retrograde cerebral perfusion was similar in matched groups. There were no differences in 30-day survival or in other major postoperative morbidity between the 2 matched cohorts.

CONCLUSIONS

A surgical strategy of MHCA + antegrade cerebral perfusion is at least as safe as DHCA during repair of acute type A aortic dissection.

Staged total arch replacement, followed by fenestrated-branched endovascular aortic repair, for patients with mega aortic syndrome

OBJECTIVE

The aim of the present study was to review the clinical outcomes of a staged approach using total arch replacement (TAR) with an elephant trunk or a frozen elephant trunk, followed by fenestrated-branched endovascular aortic repair (F-BEVAR) for patients with mega aortic syndrome.

METHODS

We reviewed the clinical data and outcomes of 11 consecutive patients (8 men; mean age, 71 ± 7 years) treated by staged TAR and F-BEVAR from January 2014 to December 2018. The F-BEVAR procedures were performed under a prospective, nonrandomized, physician-sponsored investigational device exemption protocol. All patients had had mega aortic syndrome, defined by an ascending aorta, arch, and extent I-II thoracoabdominal aortic aneurysm. The endpoints were 30-day mortality, major adverse events (MAE), patient survival, freedom from reintervention, and freedom from target vessel instability.

RESULTS

Of the 11 patients, 6 had developed chronic postdissection aneurysms after previous Stanford A (three A₁₁, two A₁₀, one A₉) dissection repair and 5 had had degenerative aneurysms with no suitable landing zone in the aortic arch. The thoracoabdominal aortic aneurysms were classified as extent I in four patients and extent II in seven. One patient had died within 30 days after TAR (9.0%). However, none of the remaining 10 patients who had undergone F-BEVAR had died. First-stage TAR resulted in MAE in three patients (27%), including one spinal cord injury. The mean length of stay was 12 ± 6 days. The mean interval between TAR and F-BEVAR was 245 ± 138 days with no aneurysm rupture during the interval. Second-stage F-BEVAR was associated with MAE in two patients (20%), including spinal cord injury in one patient from spinal hematoma due to placement of a cerebrospinal fluid drain. The mean follow-up period was 14 ± 10 months. At 2 years postoperatively, patient survival, primary patency, secondary patency, and freedom from renal-mesenteric target vessel instability was 80% ± 9%, 94% ± 6%, 100%, and 86% ± 8%, respectively. No aortic-related deaths occurred during the follow-up period. Four patients had required reintervention, all performed using an endovascular approach.

CONCLUSIONS

A staged approach to treatment of mega aortic syndrome using TAR and F-BEVAR is a feasible alternative for selected high-risk patients. Larger clinical experience and longer follow-up are needed.

Review of cerebral perfusion strategies for aortic surgery with application for minimally invasive approaches

Aortic arch and hemiarch surgery necessitate the temporary interruption of blood perfusion to the brain. Despite its complexity, hemiarch and ascending aortic surgery can be performed via a minimally invasive approach. Due to the higher risk of neurological injury during a circulatory arrest, several techniques were developed to further protect the brain during this surgery. We searched the Embase, Medline, and Cochrane databases and identified articles reporting outcomes of antegrade and retrograde cerebral perfusion strategies. Herein, we outline surgical approaches, intra-operative technical considerations, and clinical outcomes of hemiarch and ascending aortic surgery. Hemiarch and ascending aortic surgery is associated with a higher risk of mortality and morbidity. Attention to the optimal approach and cerebral protection strategy has been shown to significantly affect outcomes and mitigate risk.

Proximalized Total Arch Replacement Can Be Safely Performed by Trainee

BACKGROUND

The aim of the present study was to validate safety of total arch replacement (TAR) using a novel frozen elephant trunk device, operated by trainees as surgical education.

METHODS

Sixty-four patients including 19 patients (29.6%) with acute aortic dissection type A (AADA) underwent TAR in our institute between April 2014 and March 2019 were retrospectively analyzed. Twenty-nine patients were operated by trainees (group T) and 35 patients were operated by attending surgeons (group A).

RESULTS

Patient characteristics did not differ between groups. Operative time (409.4 ± 87.8 vs. 468.6 ± 129.6 minutes, p = 0.034), cardiopulmonary bypass time (177.7 ± 50.4 vs. 222.9 ± 596.7 minutes, p = 0.019), and hypothermic circulatory arrest time (39.5 ± 13.4 vs. 54.5 ± 18.5 minutes, p = 0.001) were significantly shorter in group A than in group T, but aortic clamping time did not differ between groups (115.3 ± 55.7 vs. 114.2 ± 35.0 minutes, p = 0.924) because the rate of concomitant surgery was higher in group A (37.1 vs. 10.3%, p = 0.014). Thirty-day mortality was 3.1% in the entire cohort. Although operation time was longer in group T, there were no significant difference in postoperative results between the groups, and the experience levels of the main operator were not independent predictors for in-hospital mortality + major postoperative complications. There was no difference in late death and aortic events between groups.

CONCLUSIONS

The present study demonstrated that TAR can be safely performed by trainees, and suggests TAR as a possible and safe educational operation.

Goal-directed cerebral perfusion in aortic arch surgery: scientific leap or hype?

Although significant advancements in cerebral protection strategies in aortic surgery have been achieved in recent years, controversy remains on what constitutes the optimal strategy. Deep hypothermic circulatory arrest alone is a viable approach in many instances, but the need for a prolonged duration of circulatory arrest and increasing case complexity have led to the utilization of adjunctive cerebral perfusion strategies. In this review, we discuss the efficacy of deep hypothermic circulatory arrest and its limitations, the role of retrograde cerebral perfusion and unilateral and bilateral antegrade cerebral perfusion, and the trend towards goal-directed perfusion strategies, all emphasizing the pressing need for randomized clinical trials to better define the optimal strategy.