Atheromatous Debris Research Articles

Enhancing Neuroprotection in Cardiac and Aortic Surgeries: A Narrative Review

Background: Neurological injury poses a significant challenge in aortic surgery, encompassing spinal cord injury from thoraco-abdominal aorta intervention or stroke post-surgery on the arch and ascending aorta. Despite ample literature and proposals, a fully effective strategy for preventing or treating neurological injury remains elusive. This narrative review aims to analyze the most common neuroprotective strategies implemented for aortic arch surgery and aortic surgery. Results: Results from the reviewed studies showed that several strategies, including deep hypothermia cardiac induction (DHCA) and cerebral perfusion techniques (retrograde cerebral perfusion, RCP, and selective anterograde cerebral perfusion, SACP) aim to mitigate these risks. Monitoring methods such as electroencephalogram (EEG), somatosensory evoked potential (SEPs), and near-infrared spectroscopy (NIRS) offer valuable insights into cerebral function during surgery, aiding in the management of hypothermia and perfusion. Pharmacological agents and blood gas management (pH stat vs. alpha stat, hematocrit level, glycemic control) are crucial in preventing post-operative complications. Additionally meticulous management of atheromatous debris is essential to minimize embolic risks during surgery. Methods: For this narrative review, PubMed, Scopus, and Medline have been used to search articles about neuroprotection strategies in aortic and aortic arch surgeries. The search was narrowed to articles between 1975 and 2024. A total of 3418 articles were initially identified to be potentially relevant for this review. A total of 66 articles were included and were found to match the inclusion criteria. Conclusions: While an overabundance of neuroprotection strategies exists for cardiac surgery, particularly in procedures involving the aorta and the arch, their efficacy varies, with some well-documented and others still under scrutiny. Further research is imperative to advance our comprehension and refine prevention techniques for cardiac-surgery-related brain injury. This is crucial given its substantial contribution to both mortality and, notably, post-operative morbidity.

The 'island technique' for aortic arch and FET surgery: an 'evergreen' or a 'rekindled flame'?

The 'island technique' for aortic arch and FET surgery: an 'evergreen' or a 'rekindled flame'?

Patient selection and anatomical considerations for zone 0 endovascular aneurysm arch repair

Endovascular aortic arch repair has been widely used in select patients who are considered high risk for open surgical repair and have suitable anatomy. The anatomical challenges of placement of stent-grafts in the ascending aorta are many, including the curved configuration, short landing zone, proximity to the aortic valve and coronary arteries and need to incorporate the supra-aortic trunks. Stent-graft designs with fenestrations and/or directional branches are applicable to patients who have suitable landing zones in the aorta and supra-aortic trunks, adequate access and absence of significant atheromatous debris. These devices include single and multibranch concepts, which are used in combination or not with cervical debranching procedures. This article summarizes the most commonly used anatomical criterion with currently utilized arch branch stent-grafts.

Stenting of ultraembolic hazardous carotid stenotic lesions using the technique of triple antiembolic protection

Objective ‒ to develop a technique of triple antiembolic protection with the simultaneous use of proximal antiembolic protection systems, distal antiembolic filters and two-layer micromesh carotid stents for carotid stenting of ultraembolic hazardous carotid stenosis. Evaluate its effectiveness and safety.Materials and methods. Since 2016, 23 carotid stenting of ultraembolic hazardous carotid stenoses has been performed using the technique of triple antiembolic protection (proximal antiembolic protection systems, distal antiembolic filters and two-layer micromesh carotid stents). All patients had symptomic stenosis: transient ischemic attacks in a certain carotid pool (n = 7), ischemic strokes (n = 16). The age of patients was from 57 to 84 years. Men prevailed among patients (n = 15). Postoperative follow-up included magnetic resonance imaging (MRI) of the brain on the first or second day after surgery with T2*, FLAIR and DWI sequences to determine the presence of «fresh» embolic ischemic foci and to exclude hemorrhagic complications. After 6 months, a control clinical examination, computed tomography or MRI of the brain, ultrasound angioscanning of the main arteries of the head were performed.Results. In all patients the patency of the carotid arteries was completely restored, and in the early postoperative period, no clinical signs of recurrent ischemic brain damage were detected in any of the cases. No signs of plaque prolapse through the stent were detected in any case. A significant amount of atheromatous debris was in 11 cases when aspirated on an external filter. In 3 cases, emboli were also detected in the distal protection filter. This fact indicates that the joint use of distal and proximal antiembolic systems reliably protects against the risk of embolism in such cases. According to MRI on the 1st or 2nd day there were no signs of «fresh» subclinical embolic ischemic foci, as well as hemorrhage. In 20 patients who underwent a follow-up examination, no signs of restenosis in the stent were recorded in any case, as well as repeated ischemic strokes. In 7 cases where the plaque had an ulcer, the ulcer resolved under the stent. Three patients are expected for a follow-up examination. According to the remote survey, these patients do not have new ischemic brain lesions. The effectiveness of the technique of triple antiembolic protection for the treatment of patients with subtotal ultraembolic hazardous carotid stenosis is indicated by the absence of clinical and neuroradiological signs of recurrent ischemic lesions.Conclusions. The technique of triple antiembolic protection for the treatment of patients with subtotal ultraembolic hazardous carotid stenoses is safe and highly effective. It is the improvement of carotid stenting results in this most dangerous group that gives reason to think about revealing the advantages of carotid stenting over carotid endarterectomy in general.

Aortic Arch Replacement With a Trifurcated Graft

The critical consideration in approaching aortic arch surgery is how best to protect the brain while providing surgical access to the cerebral vessels. Between 1999 and 2016, 285 patients underwent aortic arch replacement using the trifurcated graft technique, with 7.4% mortality (hospital/30 day). Neurologic outcomes included 5.1% temporary neurologic deficits, 3.9% permanent neurologic deficits and no spinal cord injury. The trifurcated graft technique addresses the two most important aspects of cerebral protection: minimizing cerebral ischemia and preventing cerebral embolization of air and atheromatous debris. In practice, the technique has proven to be technically straightforward and versatile, in that it is readily adapted to a variety of arch anomalies and pathologies.

TCT-546 Microvascular dysfunction after immediate versus deferred stenting in patients with acute myocardial infarction

Conventional immediate stenting (IS) in highly pro-thrombotic and inflammatory milieu of infarct related arteries (IRA) during primary percutaneous coronary intervention (PCI) would increase distal embolization of clot and atheromatous plaque debris, and provoke subsequent microvascular obstruction

Patent foramen ovale and neurologic events in patients undergoing liver transplantation.

Patent foramen ovale (PFO) is present in approximately 20% of individuals. During liver transplantation (LT), intra-operative transesophageal echocardiography can observe transient intra-cardiac shunting of atheromatous debris via a PFO. Closure of PFOs prior to LT has thus been suggested as a potential treatment to reduce peri-operative cerebral vascular accident (CVA). The objective of this study was to assess if the presence of PFO is associated with CVA in patients undergoing LT. Three hundred fifty-eight patients undergoing LT at a single academic institution were included. All patients underwent standardized cardiac evaluation including a detailed cardiovascular history and physical examination, electrocardiogram and transthoracic echocardiogram. Five patients were excluded because of poor transthoracic echocardiographic image quality, and three patients were excluded because of PFO closure prior to LT, yielding a study population of 350 patients. Medical records were reviewed to determine demographics, echocardiographic findings and outcome following LT. Major adverse cardiovascular events, myocardial infarction, CVA and death were collected. Mean age was 53.4 ± 10.2 years; 61% male and 5% of patients had a prior history of CVA. Alcohol and hepatitis C were the most common etiologies for liver disease. Forty-six patients (13.1%) were diagnosed with PFO prior to LT. In-hospital CVA occurred in 6 patients (1.7%). The prevalence of a CVA was not significantly higher in patients with PFO compared to patients without PFO, 2.2% vs 1.6%, p = 0.57. In-hospital mortality was similar in patients with PFO compared to patients without PFO, 4.4% and 5.3%, p = 1.0. The presence of a PFO in patients undergoing LT is not associated with postoperative CVA. Prophylactic closure of PFOs, in the absence of other indications, does not appear to be warranted in patients undergoing LT.

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

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

Evidence for polymicrobial communities in explanted vascular filters and atheroma debris

RationaleMicrobial communities have been implicated in a variety of disease processes and have been intermittently observed in arterial disease; however, no comprehensive unbiased community analysis has been performed. We hypothesize that complex microbial communities may be involved in chronic vascular diseases as well and may be effectively characterized by molecular assays. ObjectiveThe main objective is to survey vascular debris, atheroma, and vascular filters for polymicrobial communities consisting of prokaryotic and eukaryotic microbes, specifically eukaryotic microbes. Methods and resultsWe examined vascular aspirates of atheromatous debris or embolic protection filters in addition to matched peripheral blood samples, from fifteen patients, as well as three cadaveric coronary arteries from two separate patients, for microbial communities. General fluorescence microscopy by Höechst and ethidium bromide DNA stains, prokaryotic and eukaryotic community analysis by Next Generation DNA Sequencing (NGS), and a eukaryotic microbial 9 probe multiplexed quantitative PCR were used to detect and characterize the presence of putative polymicrobial communities. No prokaryotes were detected in peripheral blood; however, in 4 of 9 sequenced filters and in 2 of 7 sequenced atheroma debris samples, prokaryotic populations were identified. By DNA sequencing, eukaryotic microbes were detected in 4 of 15 blood samples, 5 of the 9 sequenced filters, and 3 of the 7 atheroma debris samples. The quantitative multiplex PCR detected sequences consistent with eukaryotic microbes in all 9 analyzed filter samples as well as 5 of the 7 atheroma debris samples. Microscopy reveals putative polymicrobial communities within filters and atheroma debris. The main contributing prokaryotic species in atheroma debris suggest a diverse and novel composition. Additionally, Funneliformis mosseae, an arbuscular mycorrhizal fungus in the Glomeraceae family, was detected in the coronary hard plaque from two patients. Well studied biofilm forming bacteria were not detectable in circulating peripheral blood and were not universally present in atheroma or filters. Analyses of the sequenced eukaryotes are consistent with a diverse of array poorly studied environmental eukaryotes. In summary, out of 15 patients, 6 exhibited molecular evidence of prokaryotes and 14 had molecular evidence of eukaryotic and/or polymicrobial communities in vivo, while 2 post-mortem coronary plaque samples displayed evidence of fungi. ConclusionProkaryotes are not consistently observed in atheroma debris or filter samples; however, detection of protozoa and fungi in these samples suggests that they may play a role in arterial vascular disease or atheroma formation.

Research Progress on the Risk Factors and Outcomes of Human Carotid Atherosclerotic Plaques.

Objective:Atherosclerosis is an inflammatory process that results in complex lesions or plaques that protrude into the arterial lumen. Carotid atherosclerotic plaque rupture, with distal atheromatous debris embolization, causes cerebrovascular events. This review aimed to explore research progress on the risk factors and outcomes of human carotid atherosclerotic plaques, and the molecular and cellular mechanisms of human carotid atherosclerotic plaque vulnerability for therapeutic intervention.Data Sources:We searched the PubMed database for recently published research articles up to June 2016, with the key words of “risk factors”, “outcomes”, “blood components”, “molecular mechanisms”, “cellular mechanisms”, and “human carotid atherosclerotic plaques”.Study Selection:The articles, regarding the latest developments related to the risk factors and outcomes, atherosclerotic plaque composition, blood components, and consequences of human carotid atherosclerotic plaques, and the molecular and cellular mechanisms of human carotid atherosclerotic plaque vulnerability for therapeutic intervention, were selected.Results:This review described the latest researches regarding the interactive effects of both traditional and novel risk factors for human carotid atherosclerotic plaques, novel insights into human carotid atherosclerotic plaque composition and blood components, and consequences of human carotid atherosclerotic plaque.Conclusion:Carotid plaque biology and serologic biomarkers of vulnerability can be used to predict the risk of cerebrovascular events. Furthermore, plaque composition, rather than lesion burden, seems to most predict rupture and subsequent thrombosis.

Aortic atheroma burden predicts acute cerebrovascular events after transcatheter aortic valve implantation: insights from volumetric multislice computed tomography analysis.

Embolisation of atheromatous debris during catheter manipulation is considered to underlie acute cerebrovascular events (CVE) after transcatheter aortic valve implantation (TAVI). However, the relationship between aorta atheroma burden and acute CVE after TAVI has not been established. We investigated the impact of aorta atheroma burden on acute CVE. Preoperative multislice computed tomographic (MSCT) images in 278 patients receiving TAVI were analysed. Total atheroma volume (TAV) was calculated by measuring aorta vessel and lumen areas in every 1 mm cross-sectional image. Acute CVE was observed in 16 patients. Patients having acute CVE were more likely to have a prior CVE (p=0.002), and to exhibit greater TAV in the ascending aorta (12.8±3.5 vs. 7.0±2.1 cm3, p<0.001) and the aortic arch (3.1±1.6 vs. 1.2±0.2 cm3, p<0.001). TAV in the ascending aorta >10.3 cm3 and in the aortic arch >2.9 cm3 predicted acute CVE. The incidence of acute CVE was highest (36.4%) if patients had a prior CVE and TAV in the ascending aorta and the aortic arch above cut-offs. Patients with acute CVE after TAVI had greater aorta atheroma burden. Our findings might underscore preoperative MSCT analysis of aorta atherosclerosis to identify high-risk patients for acute CVE, who might require an embolic protection device during TAVI.

Abstract 562: Evidence of Protozoan Biofilm Communities in Atheromatous Debris

Background: Evidence that vascular inflammation is an important mechanism involved in all stages of atherogenesis continues to accumulate. We hypothesize that common complex microbial involvement may be present in atheromatous debris removed from treated lesions. We evaluated this debris with metagenomic analysis. Methods: After informed consent, fifteen cases of vascular aspirate or explanted embolic filters were examined. Thirteen cases were in patients undergoing carotid stenting (3 MoMa, 10 embolic filters). One case was in a saphenous vein graft intervention (aspirate and filter) and one case was after SFA orbital atherectomy (aspirate and filter). Fluorescence microscopy, bacterial and protozoan metagenomic analysis using the RIDI™ Next Generation Sequencing (NGS) analysis system, and specific protozoan multiplex PCR probes were used to assess the presence and composition of biofilm populations. Results: Bacteria were not detected in peripheral blood; however, 4 of 12 filters and 2 of 5 atheroma debris samples had identified bacterial populations (2 patients had atheroma debris and filter evaluated). Evidence of protozoan populations was obtained in 4 of 15 peripheral blood samples, 11 of 12 filters and 4 of 5 atheroma debris samples. Microscopy illustrated a complex composition of biofilm communities in blood, devices, and atheroma debris samples. The identified bacterial taxa in atheroma debris suggest a diverse and novel population composition. Biofilm dwelling bacteria, while present in several atheroma or filter samples, were not detectable in peripheral blood and were not universally present in atheroma or filter. Taxonomic comparisons of sequenced protozoa are consistent with a diverse array of organisms similar to poorly characterized environmental protozoa. Conclusion: Of 15 patients, 6 patients had evidence of bacteria and 13 had evidence of protozoa in debris and 14 exhibited evidence of complex biofilm communities. This data suggests that biofilm forming protozoa may play a key role in arterial vascular disease.

Primary PCI: time to change focus from epicardial reperfusion towards protection of the microvasculature

Myocardial tissue perfusion remains compromised in 30-40% of patients with ST-segment elevation myocardial infarction (STEMI) despite restored epicardial patency after primary percutaneous coronary intervention (pPCI). This phenomenon is attributed to microvascular dysfunction secondary to numerous pathophysiological mechanisms, including distal embolisation of plaque and thrombus material. Its association with larger post-infarction myocardial necrosis, impaired left ventricular recovery, and worse clinical outcome illustrates the pertinence of a comprehensive armamentarium for the diagnosis, protection and treatment of microvascular dysfunction in STEMI patients. Current strategies to protect the microvasculature during pPCI are based on the assumption that distal embolisation of thrombotic and atheromatous debris is the main mechanism precipitating impaired myocardial tissue perfusion. However, recent findings suggest that this assumption is only true for the border zone of the ischaemic myocardium, whereas the infarct core consists of intramyocardial haemorrhage secondary to microvascular destruction, rather than obstruction. This observation has pertinent implications for contemporary and future adjuvant treatment strategies in STEMI patients. In this review, we provide an overview of the currently available armamentarium to assess the microvasculature, review contemporary strategies in pPCI to protect the myocardium, and discuss novel insights into microvascular pathophysiology that may help guide our focus from the coronary arteries to the microvasculature.

98 Lack of Consensus on Anti-thrombotic Therapy in Patients Undergoing Tavi – an Online Survey from Uk Tavi Operators

IntroductionThe incidence of cerebrovascular ischaemic events during and early after Trans-catheter Aortic Valve Implantation (TAVI) procedure remains a major concern. Peri-procedural events may be due to embolization of calcified material...

Treatment of saphenous vein graft disease: "never ending story" of the "eternal return".

Treatment of saphenous vein graft disease: "never ending story" of the "eternal return".

Investigation of Risks for Cerebral Embolism Associated With the Hemodynamics of Cardiopulmonary Bypass Cannula: A Numerical Model

Cerebral emboli originating in the ascending aorta are a major cause of noncardiac complications following cardiac surgery. The hemodynamics of the aortic cannula has been proven to play a significant role in emboli generation and distribution. The aim of the current study was to perform a thorough numerical investigation in order to examine the effect of the design and orientation of the cannula used during cardiopulmonary bypass on the risk to develop cerebral embolism. Hemodynamic analyses compared numerical models of 27 cases consisting of six different cannula orientations, four aortic anatomies, and three cannula designs. The cannula designs included a straight-tip (ST) cannula, a moderately curved tip cannula (TIP1 ), and a sharp-angle curved cannula (TIP2 ). Outcome measures included hemodynamic parameters such as emanating jet velocity, jet velocity drop, maximal shear stress, aortic wall reaction, emboli pathlines and distribution between upper and lower vessels, and stagnation regions. Based on these parameters, the risks for hemolysis, atheroembolism, and cerebral embolism were evaluated and compared. On one hand, the jet emerging from the ST cannula generated large wall-shear stress at the aortic wall; this may have triggered the erosion and distribution of embolic atheromatous debris from the aortic arch. On the other hand, it diverted more emboli from the clamp region to the descending aorta and thus reduced the risk for cerebral embolism. The TIP1 cannula demonstrated less shear stress on the aortic wall and diverted more emboli from the clamp region toward the upper vessels. The TIP2 cannula exhibited a stronger emanating jet, higher shear stress inside the cannula, and highly disturbed flow, which was more stagnant near the clamp region. Current findings support the significant impact of the cannula design and orientation on emboli generation and distribution. Specifically, the straight tip cannula demonstrated a reduced risk of cerebral embolism, which may be pivotal in the clinical setting.

Prospective, Randomized, Multicenter Evaluation of a Polyethylene Terephthalate Micronet Mesh–Covered Stent (MGuard) in ST-Segment Elevation Myocardial Infarction: The MASTER Trial

This study sought to evaluate the potential utility of a novel polyethylene terephthalate micronet mesh-covered stent (MGuard) in patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI). Suboptimal myocardial reperfusion after PCI in STEMI is common and results in increased infarct size and mortality. The MGuard is a novel thin-strut metal stent with a polyethylene terephthalate micronet covering designed to trap and exclude thrombus and friable atheromatous debris to prevent distal embolization. A total of 433 patients with STEMI presenting within 12 h of symptom onset undergoing PCI were randomized at 50 sites in 9 countries to the MGuard (n = 217) or commercially available bare metal or drug-eluting stents (n = 216). The primary endpoint was the rate of complete (≥70%) ST-segment resolution measured 60 to 90 min post-procedure. Baseline characteristics were well matched between the groups. The primary endpoint of post-procedure complete ST-segment resolution was significantly improved in patients randomized to the MGuard stent compared with control patients (57.8% vs. 44.7%; difference: 13.2%; 95% confidence interval: 3.1% to 23.3%; p = 0.008). By core laboratory analysis, the MGuard stent compared with control stents also resulted in superior rates of Thrombolysis In Myocardial Infarction 3 flow (91.7% vs. 82.9%, p = 0.006) with comparable rates of myocardial blush grade 2 or 3 (83.9% vs. 84.7%, p = 0.81). Mortality (0% vs. 1.9%, p = 0.06) and major adverse cardiac events (1.8% vs. 2.3%, p = 0.75) at 30 days were not significantly different between patients randomized to the MGuard stent and control stent, respectively. Among patients with acute STEMI undergoing emergent PCI, the MGuard micronet mesh-covered stent compared with conventional metal stents resulted in superior rates of epicardial coronary flow and complete ST-segment resolution. A larger randomized trial is warranted to determine whether these benefits result in reduced infarct size and/or improved clinical outcomes. (Safety and Efficacy Study of MGuard Stent After a Heart Attack [MASTER]; NCT01368471).

Simple aspiration in acute myocardial infarction: too simple to be true?

This editorial refers to ‘Impact of thrombus aspiration during primary percutaneous coronary intervention on mortality in ST-segment elevation myocardial infarction’†, by A. Noman et al. , on page 3054 Primary percutaneous coronary intervention (PCI) in ST-segment elevation myocardial infarction (STEMI) has contributed to dramatic declines in cardiovascular mortality over the last three decades.1 Nonetheless, normal myocardial perfusion is not restored in approximately one-third of patients after primary PCI, prompting investigation of novel drugs, technologies, and approaches to improve reperfusion success further. While numerous mechanisms may contribute to reperfusion failure, distal embolization of thrombus and friable atheromatous debris is believed to be ubiquitous during primary PCI, and results in microvascular obstruction.2 Preventing embolization is therefore intuitive, and theoretically should result in improved reperfusion success as measured angiographically (better epicardial and myocardial blood flow), electrocardiographically [increased ST-segment resolution (STR)], functionally (greater myocardial salvage with reduced infarct size), and clinically (enhanced survival free from heart failure events). Four types of devices have been developed to prevent embolization during PCI: distal embolic protection catheters; ‘active’ vacuum-type thrombectomy systems; manual aspiration; and micronet mesh-covered stents (the latter of which is currently undergoing investigation). Despite their innate appeal, in randomized trials distal embolic protection devices and active thrombectomy systems have surprisingly not been shown to be beneficial.3 In contrast, outcomes with ‘simple’ aspiration systems in which intracoronary thrombus is extracted through a hollow catheter prior to stent implantation have been more favourable, although not uniformly so. In TAPAS, the largest such randomized trial to date, aspiration resulted in modestly better rates of myocardial blush [without improving TIMI (Thrombolysis in Myocardial Infarction) flow or preventing macroscopic coronary thrombo-emboli] and STR, with a trend toward improved 30-day survival which became significant by 1 year.4,5 However, other trials have reported conflicting or negative results, …

Aortic arch replacement using a trifurcated graft

A critical consideration in the operative strategy for aortic arch replacement, how best to protect the brain while providing surgical access to the cerebral vessels, involves two key aspects: minimizing cerebral ischaemia and preventing cerebral embolization of air and atheromatous debris. We describe a technique, using a trifurcated branched graft, that combines hypothermic circulatory arrest, selective antegrade perfusion and axillary artery cannulation.

Cannula design reduces particulate and gaseous emboli during cardiopulmonary bypass for coronary revascularization

The incidence of neurocognitive deficits after coronary bypass surgery remains problematic, with atheroembolism being one of the major causes. External manipulation of aorta and the "sandblasting" effect of the high-velocity perfusion jet can cause dislodgement of atheromatous debris. A new arterial cannula features a tip configuration that diffuses the flow through multiple outlets, providing reduced velocity and shear with one central and three diverted flow streams. Between March 2007 and July 2008 twenty patients having isolated coronary artery bypass operations were instrumented with an Embolus Detection and Classification transducer. These data were compared to 43 patients from a previous study using similar techniques except for a standard open-tip arterial cannula. Total embolic counts were markedly lower in the new cannula group (20±25 vs 174±378) as were both gaseous (11±15 vs 95±211) and particulate counts (9±11 vs 80±194). The select 3D cannula design reduces the sandblasting effect of the perfusion jet and, also, may direct emboli from the heart and cardiopulmonary bypass equipment away from the cerebral circulation.