Antegrade Cerebral Protection Research Articles

A randomized trial comparing axillary versus innominate artery cannulation for aortic arch surgery

BackgroundCerebral protection remains the cornerstone of successful aortic surgery; however, there is no consensus as to the optimal strategy. ObjectiveTo compare the safety and efficacy of innominate to axillary artery cannulation for delivering antegrade cerebral protection during proximal aortic arch surgery. MethodsThis randomized controlled trial (The Aortic Surgery Cerebral Protection Evaluation CardioLink-3 Trial, ClinicalTrials.gov Identifier: NCT02554032), conducted across 6 Canadian centers between January 2015 and June 2018, allocated 111 individuals to innominate or axillary artery cannulation. The primary safety outcome was neuroprotection per the appearance of new severe ischemic lesions on the postoperative diffusion-weighted-magnetic resonance imaging. The primary efficacy outcome was the difference in total operative time. Secondary outcomes included 30-day all-cause mortality and postoperative stroke. ResultsOne hundred two individuals (mean age, 63 ± 11 years) were in the primary safety per-protocol analysis. Baseline characteristics between the groups were similar. New severe ischemic lesions occurred in 19 participants (38.8%) in the axillary versus 18 (34%) in the innominate group (P for noninferiority = .0009). Total operative times were comparable (median, 293 minutes; interquartile range, 222-411 minutes) for axillary versus (298 minutes; interquartile range, 231-368 minutes) for innominate (P for superiority = .47). Stroke/transient ischemic attack occurred in 4 (7.1%) participants in the axillary versus 2 (3.6%) in the innominate group (P = .43). Thirty-day mortality, seizures, delirium, and duration of mechanical ventilation were similar in both groups. Conclusionsdiffusion-weighted magnetic resonance imaging assessments indicate that antegrade cerebral protection with innominate cannulation is safe and affords similar neuroprotection to axillary cannulation during aortic surgery, although the burden of new neurological lesions is high in both groups.

Invited Commentary

Invited Commentary

Unilateral Versus Bilateral Antegrade Cerebral Protection During Aortic Surgery: An Updated Meta-Analysis

In the context of complex aortic surgery, despite the wide consensus about the use of moderate hypothermia in association with antegrade selective cerebral perfusion (ASCP), its bilateral administration is not always warranted. The aim of the present meta-analysis was to investigate outcomes of unilateral versus bilateral ASCP. Outcomes investigated were postoperative mortality and neurologic permanent and temporary disease (PND and TND); separate analysis of heterogeneity using the Cochrane Q statistic was used to perform comparisons. Circulatory arrest (CA) time and temperature, and sample size were explored as potential causes for heterogeneity with meta-regression analysis. The study population consisted of 3,723 patients receiving bilateral ASCP and 3,065 patients receiving unilateral ASC. Pooled analysis showed similar rates of postoperative mortality: 9.8% (95% confidence interval [CI], 7.8% to 12.3%) for bilateral ASCP versus 7.6% (95% CI, 5.7% to 10.2%) for unilateral ASCP; p= 0.19. Postoperative PND rates as well did not differ significantly: 6.9% (95% CI, 5.0% to 9.4%) for bilateral ASCP versus 5.8% (95% CI, 3.8% to 8.7%) for unilateral ASCP; p= 0.53. Similar results yielded from TND analysis: 9.3 % (95% CI, 7.0% to 12.2%) versus 6.5% (95% CI, 4.5% to 9.5%), respectively, p= 0.14. Meta-regression analysis showed that longer CA times were associated with significantly increased mortality only among patients administered with unilateral ASCP (model Q 65.8, p < 0.0001). Furthermore, higher CA temperatures were associated with significantly reduced rates of mortality (Q 64.1, p= 0.001), PND (Q 52.3, p= 0.01), and TND (Q 62.2, p= 0.002) in both groups. Unilateral versus bilateral ASCP administration did not result in different mortality and neurologic morbidity rates. Nevertheless, among prolonged CA times unilateral ASCP resulted in poorer outcomes with respect to bilateral ASCP. Furthermore, moderate hypothermia was associated with best outcomes in both groups.

Direct innominate artery cannulation for selective antegrade cerebral perfusion during deep hypothermic circulatory arrest in aortic surgery

To demonstrate a novel, reproducible, and effective method of direct innominate artery cannulation using a 14 F pediatric venous cannula to establish antegrade cerebral protection (ACP) in patients undergoing aortic surgery that requires an open distal anastomosis or hemiarch replacement. We reviewed prospectively gathered data on all patients who had undergone replacement of the ascending aorta or hemiarch with an open distal anastomosis using deep hypothermic circulatory arrest and direct innominate artery cannulation with a 14 F pediatric venous cannula at our institution. After central cannulation and cooling to 25 °C to 28 °C, all patients had ACP initiated by way of a direct innominate cannula placed over a guidewire. Fifty patients underwent direct innominate artery cannulation with our technique from 2010 to 2012. The operative mortality was 2% (n = 1), and the rates of neurologic morbidity were acceptable and similar to those with other methods of ACP delivery: stroke (2%, n = 1), seizure (0%, n = 0), and delirium (18%, n = 9). The mean operative time was 31 ± 9, 19 ± 5, 100 ± 39, 141 ± 39, and 259 ± 63 minutes for cooling, circulatory arrest, crossclamp, cardiopulmonary bypass, and total operative time, respectively. No local or arterial complications were observed. Direct cannulation of the innominate artery using a 14 F pediatric venous cannula is a simple, reproducible, safe, and effective technique for establishing ACP in patients undergoing aortic surgery that requires an open distal anastomosis or hemiarch replacement. This technique avoids the additional time and potential local complications associated with other established methods for delivering ACP, such as axillary cannulation.

Successful surgical repair of acute type A aortic dissection without the use of blood products

We report successful surgical treatment of type A aortic dissection in a Jehovah's Witness without the use of any blood products. An interposition graft replacement of the ascending aorta was carried out. This was under right axillo-atrial cardiopulmonary bypass with antegrade cerebral perfusion via right a subclavian and left carotid cannula for 24 minutes at 28°C. Body temperature was kept at 32°C throughout. Autologous transfusion was deployed using cell salvage and a preoperative haemodilution technique. The patient was given tranexamic acid, desmopressin, recombinant factor VIIa, folic acid and epoetin alfa. Patients who object to transfusion represent a significant challenge, especially those who are at a high risk of coagulopathy associated with inherent aortic dissection leading to perturbed haemodynamics, cardiopulmonary bypass and hypothermic circulatory arrest. Type A aortic dissection repair is possible in patients refusing the use of blood products with blood salvage techniques and synthetic products that can limit the risk of bleeding. Minimal hypothermia is vital to preserve platelet function and avoid coagulopathy. Thus, a combination of normothermic/minimal hypothermia and antegrade cerebral protection with a blood conservation strategy can be deployed for a successful surgical outcome in aortic dissection without transfusion.

Innominate artery reconstruction during emergent surgery for acute aortic dissection

Case description This is a case of acute aortic dissection with multiple tears, occluding innominate artery and causing brain and right hand malperfusion. Patient underwent successful emergent surgery in deep hypothermic circulatory arrest with antegrade cerebral protection for complete replacement of innominate artery and hemiarch. Complete innominate artery was replaced during cooling period on 22°C.

Unilateral versus bilateral antegrade cerebral protection during circulatory arrest in aortic surgery: A meta-analysis of 5100 patients

Our objective was to determine whether the use of unilateral (u-ACP) or bilateral antegrade cerebral perfusion (b-ACP) results in different mortality and neurologic outcomes after complex aortic surgery. PubMed, Embase, and the Cochrane Library were searched for studies reporting on postoperative mortality and permanent (PND) and temporary neurologic dysfunction (TND) in complex aortic surgery requiring circulatory arrest with antegrade cerebral protection. Analysis of heterogeneity was performed with the Cochrane Q statistic. Twenty-eight studies were analyzed for a total of 1894 patients receiving u-ACP versus 3206 receiving b-ACP. Pooled analysis showed similar rates of 30-day mortality (8.6% vs 9.2% for u-ACP and b-ACP, respectively; P=.78), PND (6.1% vs 6.5%; P=.80), and TND (7.1% vs 8.8%; P=.46). Age, sex, and cardiopulmonary bypass time did not influence effect size estimates. Higher rates of postoperative mortality and PND were among nonelective operations and for highest temperatures and duration of the circulatory arrest. The Egger test excluded publication bias for the outcomes investigated. This meta-analysis shows that b-ACP and u-ACP have similar postoperative mortality and bothPND and TND rates after circulatory arrest for complex aortic surgery.

Antegrade versus Retrograde Cerebral Protection in Repair of Acute Ascending Aortic Dissection

The objective of this study was to compare retrograde with antegrade cerebral protection during acute aortic dissection repair using cerebral oximetry measurements. Fifty consecutive acute ascending aortic dissection repairs were analyzed. Cerebral oximetry data were collected for 41 of 50. Eight patients who had antegrade cerebral protection alone and 29 of 41 had retrograde cerebral protection alone. The per cent change in cerebral oximetry values during deep hypothermic circulatory arrest from baseline and from prearrest values was compared for the two groups using Student t test. The per cent change from baseline for the antegrade patients was: right 13.8 per cent and left -2.5 per cent; the per cent change from baseline for retrograde patients was: right 0.8 per cent and left 0.2 per cent (P values 0.216 and 0.725, respectively). The per cent change from the prearrest value for the antegrade patients was: right -12 per cent and left -15 per cent; the per cent change from prearrest for retrograde patients was: right -15 per cent and left -16 per cent (P values 0.514 and 0.956, respectively). No compelling evidence for an advantage to either antegrade or retrograde cerebral perfusion was detected. Further study with a focus on neurologic outcomes is warranted.

Antegrade cerebral protection in thoracic aortic surgery: lessons from the past decade☆

Prolonged deep hypothermic circulatory arrest (DHCA) adversely affects outcome and quality of life in thoracic aortic surgery. Several techniques of antegrade cerebral perfusion are routinely used: bilateral selective antegrade cerebral protection (SACP) by introducing catheters in the innominate and left carotid artery, unilateral perfusion through the right axillary antegrade cerebral perfusion (RAACP) or a combination of right axillary perfusion with an additional catheter in the left carotid artery (RAACCP), resulting also in bilateral perfusion. The aim of the present study was to analyse the impact of the different approaches on the quality of life (QoL). The data of 292 patients who underwent surgery of the thoracic aorta using DHCA at our hospital between January 2004 and December 2007 have been analysed and a follow-up was performed focussing on QoL, assessed with the Short Form-36 Health Survey Questionnaire (SF-36). Results were analysed according to the type of cerebral perfusion and the duration of DHCA. Patients' characteristics were similar in all groups. Of the total, 3.4% patients underwent DHCA (average 8.3+/-6.4 min) without ACP, 45.9% underwent SACP (average DHCA of 15.6+/-7.1 min), 40.4% had RAACP (average DHCA of 28.1+/-11.6 min) and 9.4% bilateral perfusion (RAACCP) (average DHCA of 43.1+/-16.7 min). The average follow-up was 23.2+/-15.1 months. QoL was preserved in all groups. For DHCA above 40 min, bilateral ACP provides superior midterm QoL than unilateral RAACP (average SF-36 95.1+/-44.4 vs 87.6+/-31.3; p=0.072). When midterm QoL is assessed, bilateral SACP provides the best cerebral protection for prolonged DHCA (>40 min).