Cerebral Diffusion-weighted Magnetic Resonance Imaging Research Articles

Impact of high-power short-duration atrial fibrillation ablation technique on the incidence of silent cerebral embolism: a prospective randomized controlled study

BackgroundHigh-power short-duration (HPSD) ablation strategy has emerged as a popular approach for treating atrial fibrillation (AF), with shorter ablation time. The utilized Smart Touch Surround Flow (STSF) catheter, with 56 holes around the electrode, lowers electrode-tissue temperature and thrombus risk. Thus, we conducted this prospective, randomized study to investigate if the HPSD strategy with STSF catheter in AF ablation procedures reduces the silent cerebral embolism (SCE) risk compared to the conventional approach with the Smart Touch (ST) catheter.MethodsFrom June 2020 to September 2021, 100 AF patients were randomized 1:1 to the HPSD group using the STSF catheter (power set at 50 W) or the conventional group using the ST catheter (power set at 30 to 35 W). Pulmonary vein isolation was performed in all patients, with additional lesions at operator’s discretion. High-resolution cerebral diffusion-weighted magnetic resonance imaging (hDWI) with slice thickness of 1 mm was performed before and 24–72 h after ablation. The incidence of new periprocedural SCE was defined as the primary outcome. Cognitive performance was assessed using the Montreal Cognitive Assessment (MoCA) test.ResultsAll enrolled AF patients (median age 63, 60% male, 59% paroxysmal AF) underwent successful ablation. Post-procedural hDWI identified 106 lesions in 42 enrolled patients (42%), with 55 lesions in 22 patients (44%) in the HPSD group and 51 lesions in 20 patients (40%) in the conventional group (p = 0.685). No significant differences were observed between two groups regarding the average number of lesions (p = 0.751), maximum lesion diameter (p = 0.405), and total lesion volume per patient (p = 0.669). Persistent AF and CHA2DS2-VASc score were identified as SCE determinants during AF ablation procedure by multivariable regression analysis. No significant differences in MoCA scores were observed between patients with SCE and those without, both immediately post-procedure (p = 0.572) and at the 3-month follow-up (p = 0.743).ConclusionsInvolving a small sample size of 100 AF patients, this study reveals a similar incidence of SCE in AF ablation procedures, comparing the HPSD strategy using the STSF catheter to the conventional approach with the ST catheter.Trial registrationClinicaltrials.gov: NCT04408716.Graphical AF = Atrial fibrillation, DWI = Diffusion-weighted magnetic resonance imaging, HPSD = High-power short-duration, ST = Smart Touch, STSF = Smart Touch Surround Flow.

Microstructural Changes in the Spinothalamic Tract of CPSS Patients: Preliminary Results from a Single-Center Diffusion-Weighted Magnetic Resonance Imaging Study.

Chronic pain after spinal surgery (CPSS), formerly known as failed back surgery syndrome, encompasses a variety of highly incapacitating chronic pain syndromes emerging after spinal surgery. The intractability of CPSS makes objective parameters that could aid classification and treatment essential. In this study, we investigated the use of cerebral diffusion-weighted magnetic resonance imaging. Cerebral 3T diffusion-weighted (DW-) MRI data from adult CPSS patients were assessed and compared with those of healthy controls matched by age and gender. Only imaging data without relevant artefacts or significant pathologies were included. Apparent diffusion coefficient (ADC) maps were calculated from the b0 and b1000 values using nonlinear regression. After skull stripping and affine registration of all imaging data, ADC values for fifteen anatomical regions were calculated and analyzed with independent samples T-tests. A total of 32 subjects were included (sixteen CPSS patients and sixteen controls). The mean ADC value of the spinothalamic tract was found to be significantly higher in CPSS patients compared with in healthy controls (p = 0.013). The other anatomical regions did not show statistically different ADC values between the two groups. Our results suggest that patients suffering from CPSS are subject to microstructural changes, predominantly within the cerebral spinothalamic tract. Additional research could possibly lead to imaging biomarkers derived from ADC values in CPSS patients.

A single-center pilot randomized controlled trial of atorvastatin loading for preventing ischemic brain damage after carotid artery stenting.

Carotid artery stenting (CAS) performed perioperatively with high-dose atorvastatin may reduce the incidence of new ischemic brain lesions, but more high-level evidence is needed. Furthermore, the optimal dose and course of perioperative statin therapy remain uncertain. A single-center, prospective, parallel controlled, pilot randomized clinical trial was conducted at Beijing Hospital. The study includes a total of 130 patients with CAS. The patients were randomly assigned to receive a high-dose of 80 mg/day atorvastatin (n = 65) or a standard-dose of 20 mg/day atorvastatin (n = 65) 3 days before and 3 days after planned CAS. The primary endpoint event was the cumulative incidence of silent new ischemic cerebral lesions (sNICL) on post-CAS cerebral diffusion-weighted magnetic resonance imaging (DW-MRI), transient ischemic attack (TIA), or ischemic stroke within 30 days after CAS. Among the 130 patients, 123 completed the study, of which 63 were in the high-dose group and 60 were in the standard-dose group. The incidence of major endpoint events was 69.8% (44 cases) and 78.3% (46 cases) in the high-dose and standard-dose groups, respectively. There was no significant difference between the two groups (HR, 0.705; 95% CI, 0.315-1.576; p = 0.393). According to the stratified analysis results, the sNICL incidence was significantly different between the two groups in the symptomatic patients (HR, 0.263; 95% CI, 0.70-0.984; p = 0.04). Among patients with CAS, a periprocedural high-dose of atorvastatin did not reduce the rate of periprocedural ischemic brain damage. However, high-dose statins can reduce the incidence of sNICL after CAS in patients with symptomatic carotid stenosis. Clinicaltrials.gov, identifier NCT03079115.

Plaque morphology effect on periprocedural asymptomatic cerebral embolism in carotid artery stenting using first-generation carotid stents: A diffusion-weighted magnetic resonance imaging study.

Silent cerebral embolism with carotid artery stenting (CAS) may contribute to dementia and cognitive decline. Moreover, clinically silent embolism is an important index of peri-procedural stroke risk. The purpose of this study was to compare the periprocedural asymptomatic cerebral embolism rates of CAS procedures performed for noncalcified and calcified carotid artery plaques using diffusion-weighted magnetic resonance imaging (DW-MRI). Five hundred and seventy clinically uncomplicated patients who underwent CAS at our center from December 2010 to June 2020 (mean [standard deviation, SD] age 69.3 [8.2 years]) were analyzed retrospectively. The patients were divided into 2 groups with noncalcified (268 patients) and calcified (302 patients) plague. Cerebral DW-MRI was performed for the patients before and after CAS and compared. The presence of periprocedural new ipsilateral diffusion limitations detected on cerebral DW-MRI was noted as a significant finding. Ipsilateral diffusion limitations of the non-calcified and calcified plaque groups detected on cerebral DW-MRI were compared. The presence of periprocedural asymptomatic ipsilateral DW-MRI lesions was higher in patients in the noncalcified plaque group (45 [16.8%]) than in patients in the calcified plaque group (31 [10.3%]; P = 0.02). This study demonstrated that the rate of ipsilateral asymptomatic cerebral embolism detected on cerebral DW-MRI was higher in the CAS procedures performed for noncalcified carotid artery plaques than in those performed for calcified plaques.

Increased Intima-Media Thickness of the Ascending Aorta May Predict Neurological Complications Associated with TAVI

ObjectivesNeurological complications associated with transcatheter aortic valve implantation (TAVI) are important due to its morbidity and mortality risks. The purpose of this study was to investigate the importance of the features of the aortic valve and ascending aorta to predict the neurological complications associated with TAVI. MethodsThe patients for whom the heart team decided to perform TAVI were included in the study. In order to assess possible neurological complications, cerebral diffusionweighted magnetic resonance imaging(MRI) was performed pre- and post-operatively. The diameter of the patients' aortic root and ascending aorta, aortic valve scores, intima media thickness of the ascending aorta were measured from their transesophageal echocardiography records. ResultsA total of 108 patients constituted the study population. 31 patients were found to develop a new lesion (MR+) detected on MRI after TAVI, while 76 patients did not have any new lesions (MR-). The groups did not have any significant differences in their aortic valve features and scores. However, AA-IMT was found to be higher in the MR+ group (1.8mm [1.6-2.3] vs 1.4mm [1.2-1.8] interquartile range). The multivariate logistic regression analysis conducted to detect new lesions revealed that AA-IMT led to a significantly increased risk. ConclusionThe features of the ascending are more important than the demographic characteristics of patients and features of the native valve in predicting new lesions on MRI scans and thus neurological events after TAVI.

Silent Brain Infarction After Endovascular Arch Procedures: Preliminary Results from the STEP Registry

Few data exist concerning the rate of silent cerebral ischaemic events following endovascular treatment of the aortic arch. The objective of this work was to quantify these lesions using the STEP registry (NCT04489277). This multicentre retrospective cohort study included consecutive patients treated with an aortic endoprosthesis deployed in Ishimaru zone 0–3 and brain diffusion weighted magnetic resonance imaging (DW-MRI) within seven days following the procedure. DW-MRI was performed to identify the location and number of new silent brain infarctions (SBI). All endografts were carbon dioxide flushed prior to implantation. The study population included 91 patients (mean age, 69 years; men, 64%) from two academic centres treated between September 2018 and January 2020. The procedure was elective in 71 patients (78%). The treatment was performed for a dissection, degenerative aneurysm, or other aortic disease in 44 (49%), 34 (37%), and 13 (14%) patients, respectively. Endografts were deployed in zone 0, 1, 2 or 3 in 23 (25%), 10 (11%), 47 (52%), and 11 (12%) patients, respectively. Endografts were branched (25%), fenestrated (17%), or tubular (58%). At 30 days, there were no deaths or clinical strokes. On cerebral DW-MRI, a total of 245 SBI were identified in 45 patients (50%). Lesions were in the left hemisphere in 63% of the patients (153/245), predominantly in the middle territory (94/245). Deployment in zone 0–1 (p = .026), placement of a branched or fenestrated endograft (p = .038), a proximal endoprosthesis diameter ≥ 40 mm (p = .038), and an urgent procedure (p = .005) were significantly associated with the presence of SBI on univariable analysis, while urgent procedure was found to be an independent predictor on multivariable analysis (binary logistic regression) (p = .002). SBI following endovascular repair of the aortic arch is frequent, although there were no clinical strokes. Innovative strategies to reduce the risk of embolisation need to be developed.

Silent Brain Infarction After Endovascular Arch Procedures: Preliminary Results from the STEP Registry

Few data exist concerning the rate of silent cerebral ischaemic events following endovascular treatment of the aortic arch. The objective of this work was to quantify these lesions using the STEP registry (NCT04489277). This multicentre retrospective cohort study included consecutive patients treated with an aortic endoprosthesis deployed in Ishimaru zone 0-3 and brain diffusion weighted magnetic resonance imaging (DW-MRI) within seven days following the procedure. DW-MRI was performed to identify the location and number of new silent brain infarctions (SBI). All endografts were carbon dioxide flushed prior to implantation. The study population included 91 patients (mean age, 69 years; men, 64%) from two academic centres treated between September 2018 and January 2020. The procedure was elective in 71 patients (78%). The treatment was performed for a dissection, degenerative aneurysm, or other aortic disease in 44 (49%), 34 (37%), and 13 (14%) patients, respectively. Endografts were deployed in zone 0, 1, 2 or 3 in 23 (25%), 10 (11%), 47 (52%), and 11 (12%) patients, respectively. Endografts were branched (25%), fenestrated (17%), or tubular (58%). At 30 days, there were no deaths or clinical strokes. On cerebral DW-MRI, a total of 245 SBI were identified in 45 patients (50%). Lesions were in the left hemisphere in 63% of the patients (153/245), predominantly in the middle territory (94/245). Deployment in zone 0-1 (p=.026), placement of a branched or fenestrated endograft (p=.038), a proximal endoprosthesis diameter≥40mm (p=.038), and an urgent procedure (p=.005) were significantly associated with the presence of SBI on univariable analysis, while urgent procedure was found to be an independent predictor on multivariable analysis (binary logistic regression) (p=.002). SBI following endovascular repair of the aortic arch is frequent, although there were no clinical strokes. Innovative strategies to reduce the risk of embolisation need to be developed.

Silent cerebral lesions and cognitive function after pulmonary vein isolation with an irrigated gold-tip catheter: REDUCE-TE Pilot study.

IntroductionStroke is one of the most feared complications during catheter ablation of atrial fibrillation (AF). While symptomatic thromboembolic events are rare, magnetic resonance imaging (MRI) may identify asymptomatic (ie, silent) cerebral lesions (SCLs) following pulmonary vein isolation (PVI) procedures.Methods and ResultsThe REDUCE‐TE Pilot was a prospective multicenter, single‐arm observational study investigating the incidence of SCL in patients with symptomatic paroxysmal AF undergoing PVI with a novel gold‐tip, externally irrigated ablation catheter. After ablation, cerebral diffusion‐weighted MRI and a postablation follow‐up were performed at 1 to 3 days after the ablation procedure. A neurocognitive test was done before and after ablation. The primary study endpoint was the occurrence of one or more new SCLs. Secondary study endpoints included neurocognitive status, procedural success rate, and periprocedural complications including symptomatic thromboembolic events. A total of 104 patients were enrolled (69% male, mean age: 61.5 ± 9.7 years, mean CHA2DS 2‐VASc score: 1.7 ± 1.2). Postprocedural MRI examination was performed in 97 patients, and in nine of them (9.3%; 95% CI: 4.3‐16.9%) a total of 11 SCLs were detected. Univariate analyses did not reveal any significant predictor for new SCLs. Nonsignificant trends were observed for low activated clotting time during ablation and for international normalized ratio value outside the range of 2 to 3 at ablation. There was no evidence of significant deterioration of neurocognitive function after PVI. In four patients, a pericardial tamponade was noted but all patients fully recovered during follow‐up.ConclusionsAblation of AF using a novel gold‐tip, externally irrigated ablation catheter, resulted in SCLs in approximately one out of 10 patients without a measurable effect on neurocognitive function.

Cerebral Thromboembolic Events During Anterior Cervical Spine Surgery: Retrospective Case Series Study With Diffusion-Weighted Magnetic Resonance Imaging Follow-up in the Immediate Postoperative Period.

ObjectiveWe evaluated the efficacy of diffusion-weighted magnetic resonance imaging (DW-MRI) in detecting perioperative cerebral thromboembolic events after anterior cervical discectomy and fusion (ACDF).MethodsThis retrospective case series included 51 consecutive patients that underwent ACDF. To assess baseline presence of plaque or stenosis, all patients were assessed for risk factors of cerebrovascular events and underwent carotid ultrasound preoperatively and cerebral DW-MRI was performed in all patients postoperatively, with areas of high signal intensity interpreted as a cerebral thromboembolic event. ResultsOne male patient who underwent a C4/5 ACDF had a focal diffusion abnormality on DW-MRI concerning for cerebral thromboembolic events in the right posterior cerebral artery territory. He remained asymptomatic and did not display related neurological symptoms, such as visual deficits. ConclusionAsymptomatic cerebral thromboembolic events can be detected by DW-MRI after ACDF. The incidence of such events remains very rare despite the direct manipulation and associated alteration of common carotid artery flow dynamics.

Embolic protection in patients undergoing transaortic transcatheter aortic valve replacement: initial experience with the TriGuard HDH embolic deflection device.

Stroke remains one of the most worrisome complications following transcatheter aortic valve replacement (TAVR). This pilot study evaluates the safety, feasibility, and exploratory efficacy of the TriGuard HDH embolic deflection device (Keystone Heart Ltd., Caesarea, Israel) in patients undergoing transaortic TAVR. A total of 10 patients (median age: 81 years, STS score: 9.6 ± 5.6%) undergoing transaortic TAVR were included. All 30-day events were recorded and defined according to Valve Academic Research Consortium-2 criteria. Cerebral diffusion-weighted magnetic resonance imaging exams were planned preprocedure and within 10 days post-TAVR. The results of the magnetic resonances were analyzed in an independent core laboratory blinded to clinical data. Neurocognitive evaluation tests (Montreal Cognitive Assessment, Cogstate, Digit Symbol Substitution Test, Word Fluency Test, and Trailmaking tests) were performed at baseline, and within 10 and 30 days post-TAVR. The TriGuard HDH device was successfully deployed in all patients without complications. There was one procedural major vascular complication unrelated to the study device, and no clinically apparent stroke events were observed at 30-day follow-up. Cerebral diffusion weighted magnetic resonance imaging exams were performed in six patients at 7.5 ± 1.9 days post-TAVR showing the presence of new ischemic lesions in five patients (83.3%), which were single lesions in 60% of these individuals. Paired neurocognitive evaluation tests demonstrated no significant changes in neurocognitive parameters over time. This study shows the safety and feasibility of using the TriGuard HDH embolic protection device in transaortic TAVR. Further studies are warranted to determine the efficacy of embolic protection in this population.

Silent cerebral injury after transcatheter aortic valve implantation and the preventive role of embolic protection devices: A systematic review and meta-analysis

BackgroundThe aims of this study were: 1) to evaluate silent cerebral injury detected by cerebral diffusion weighted magnetic resonance imaging (DW-MRI) after transcatheter aortic valve implantation (TAVI); and 2) to assess the efficacy of embolic protection devices (EPDs) on DW-MRI endpoints. MethodsWe included in a pooled analysis 25 prospective studies reporting post-procedural cerebral DW-MRI data after TAVI (n=1225). Among these studies, we included in a meta-analysis 6 studies investigating TAVI performed with versus without EPDs (n=384). Primary endpoints were the number of new lesions per patient and the total lesion volume, while secondary endpoints were the number of patients with new lesions and the single lesion volume. ResultsThe main pooled DW-MRI outcomes were: patients with new ischemic lesions, 77.5% (95% confidence interval=71.7–83.3%); total lesion volume, 437.5mm3 (286.7–588.3mm3); single lesion volume, 78.1mm3 (56.7–99.5mm3); and number of new lesions per patient, 4.2 (3.4–5.0). The use of EPDs was associated with a significant reduction in total lesion volume (mean difference [95% confidence interval]=−111.1mm3 [−203.6 to −18.6mm3]; p=0.02) and single lesion volume (−12.1mm3 [−18.3 to −6.0mm3]; p=0.0001) after TAVI. ConclusionsSilent cerebral injury occurs in the majority of patients undergoing TAVI and DW-MRI allows a precise characterization of new ischemic brain lesions. EPDs reduce the total and single volume of such lesions detected after the procedure, although the number of new lesions per patient and the number of patients with new lesions are not significantly reduced by such devices.

Cerebral Effects of Targeted Temperature Management Methods Assessed by Diffusion-Weighted Magnetic Resonance Imaging

The aim of this randomized porcine study was to compare surface targeted temperature management (TTM) to endovascular TTM evaluated by cerebral diffusion-weighted magnetic resonance imaging (MRI): apparent diffusion coefficient (ADC), and by intracerebral/intramuscular microdialysis. It is well known that alteration in the temperature affects ADC, but the relationship between cerebral ADC values and the cooling method per se has not been established. Eighteen anesthetized 60-kg female swine were hemodynamically and intracerebrally monitored and subsequently subjected to a baseline MRI. The animals were then randomized into three groups: (1) surface cooling (n = 6) at 33.5°C using EMCOOLSpad®, (2) endovascular cooling (n = 6) at 33.5°C using an Icy® cooling catheter with the CoolGard 3000®, or (3) control (n = 6) at 38.5°C using a Bair Hugger™. The swine were treated with TTM for 6 hours followed by a second MRI examination, including ADC. Blood and microdialysate were sampled regularly throughout the experiment, and glucose, lactate, pyruvate, glycerol, and the lactate/pyruvate ratio did not differ among groups, neither intracerebrally nor intramuscularly. Surface cooling yielded a significantly lower median ADC than endovascular cooling: 714 (634; 804) × 10-6 mm2/s versus 866 (828; 927) × 10-6 mm2/s, (p < 0.05). The surface cooling ADC was lowered to a range usually attributed to cytotoxic edema and these low values could not be explained solely by the temperature effect per se. To what extent the ADC is fully reversible at rewarming is unknown and the clinical implications should be further investigated in clinical studies.

Abstract 11735: Periprocedural Cerebral Ischemic Events With TAVI Performed Without Prior Balloon Dilatation of the Aortic Valve: A Randomized Prospective Study

Introduction: Balloon aortic valvuloplasty (BAV) is considered as an essential part of Transcatheter Aortic Valve Implantation (TAVI) procedure, but cerebral embolization may occur during this step. Hypothesis: We assessed the hypothesis that TAVI performed without prior BAV may be associated with decrease of risk of periprocedural cerebral ischemia assessed using diffusion-weighted (DW) magnetic resonance imaging (MRI). Methods: In this prospective monocentric study we randomized consecutive patients who underwent TAVI with the new generation balloon expandable SAPIEN 3 prosthesis. Group 1 (n=14) included patients with BAV performed prior implantation of the prosthesis and group 2 (n=14) patients with direct implantation of the valve. Periprocedural cerebral ischemia was assessed blindly by neurological testing and serial cerebral DW MRI at baseline and within 3 days after TAVI. Results: On the 28 patients included, mean age was 83 years (78-86),18 were of female gender (64.3%) and mean logistic Euroscore II was 8.4 (6.3-10.6) without significant differences between the 2 groups. Implantation of the valve was successful in all patients. Considering the total population, preexisting silent ischemic brain abnormalities were observed in 11 patients (39.3%) and microbleeds in 14 patients (50 %). New foci of restricted diffusion, mainly lacunar, and new microbleeds were found on cerebral DW MRI in respectively 13 (46.4%) and 6 (21%) patients after the procedure without significant difference between the 2 groups (table 1). There were neither apparent impairments of neurocognitive function or neurological events during the in-hospital stay in the 2 groups. In conclusion: Direct implantation of new generation balloon expandable prosthesis appears feasible but is not associated with reduction of periprocedural ischemic cerebral events . These results argue for embolization occurring during positioning of the valve rather than during balloon valvuloplasty.

The Incidence and the Risk Factors of Silent Embolic Cerebral Infarction After Coronary Angiography and Percutaneous Coronary Interventions.

Silent embolic cerebral infarction (SECI) is a major complication of coronary angiography (CAG) and percutaneous coronary intervention (PCI). Patients with stable coronary artery disease (CAD) who underwent CAG with or without PCI were recruited. Cerebral diffusion-weighted magnetic resonance imaging was performed for SECI within 24 hours. Clinical and angiographic characteristics were compared between patients with and without SECI. Silent embolic cerebral infarction occurred in 12 (12%) of the 101 patients. Age, total cholesterol, SYNTAX score (SS), and coronary artery bypass history were greater in the SECI(+) group (65 ± 10 vs 58 ± 11 years,P= .037; 223 ± 85 vs 173 ± 80 mg/dL,P= .048; 30.1 ± 2 vs 15 ± 3,P< .001; 4 [33.3%] vs 3 [3.3%],P= .005). The SECI was more common in the PCI group (8/24 vs 4/77,P= .01). On subanalysis, the SS was significantly higher in the SECI(+) patients in both the CAG and the PCI groups (29.3 ± 1.9 vs 15 ± 3,P< .01; 30.5 ± 1.9 vs 15.1 ± 3.2,P< .001, respectively). The risk of SECI after CAG and PCI increases with the complexity of CAD (represented by the SS). The SS is a predictor of the risk of SECI, a complication that should be considered more often after CAG.

Intraaortic Protection From Embolization in Patients Undergoing Transaortic Transcatheter Aortic Valve Implantation

Transcatheter aortic valve implantation (TAVI) results in the dislodgement of debris with risk of cerebral lesions or stroke. The EMBOL-X protection device (Edwards Lifesciences, Irvine, CA) is positioned within the ascending aorta to capture such debris. Between July 2012 and April 2014 we randomly assigned 30 high-risk patientsto undergo transaortic TAVI with the SAPIEN XT prosthesis (Edwards Lifesciences) combined with either the EMBOL-X device (group-1, n= 14) or without (group-2, n= 16). Periprocedural cerebral lesions were assessed by diffusion-weighted magnetic resonance imaging (DW-MRI) at baseline and within 7 days post-procedurally. New foci of restricted diffusion on cerebral DW-MRI were found in 69% in group-2 and 50% in group-1. Lesion size was smaller in patients treated with the EMBOL-X device than in those without (88 ± 60 vs 168 ± 217 mm(3), p= 0.27, t= 1.2, degrees of freedom= 10). Transaortic TAVI patients treated with the EMBOL-X device had significantly smaller lesion volumes in the supply region of the middle cerebral artery (33 ± 29 vs 76 ± 67 mm(3), p= 0.04). There were no neurologic events after transaortic TAVI. The intraaortic protection device seems to reduce both the incidence and the volume of new cerebral lesions (ClinicalTrials.gov number, NCT01735513).

A prospective randomized evaluation of the TriGuard™ HDH embolic DEFLECTion device during transcatheter aortic valve implantation: results from the DEFLECT III trial.

To evaluate the safety, efficacy, and performance of the TriGuard™ HDH Embolic Deflection Device (TriGuard) compared with no cerebral protection in patients undergoing transcatheter aortic valve implantation (TAVI). From February 2014 to March 2015, 85 subjects undergoing TAVI at 13 centres in Europe and Israel were randomized to TriGuard protection vs. no protection. Subjects underwent neurologic and cognitive evaluation at baseline, pre-discharge and 30 days; cerebral diffusion-weighted magnetic resonance imaging was performed at 4 ± 2 days post-procedure and at 30 days. Technical success, which included complete 3-vessel cerebral coverage, was achieved in 88.9% (40/45) of cases. The primary in-hospital procedural safety endpoint (death, stroke, life-threatening or disabling bleeding, stage 2 or 3 acute kidney injury, or major vascular complications) occurred in 21.7% of TriGuard and 30.8% of control subjects (P = 0.34). In the Per Treatment population (subjects with complete three-vessel cerebral coverage), TriGuard use was associated with greater freedom from new ischaemic brain lesions (26.9 vs. 11.5%), fewer new neurologic deficits detected by the National Institutes of Health Stroke Scale (3.1 vs. 15.4%), improved Montreal Cognitive Assessment (MoCA) scores, better performance on a delayed memory task (P = 0.028) at discharge, and a >2-fold increase in recovery of normal cognitive function (MoCA score >26) at 30 days. TriGuard cerebral protection during TAVI is safe and complete cerebral vessel coverage was achieved in 89% of subjects. In this exploratory study, subjects undergoing protected TAVI had more freedom from ischaemic brain lesions, fewer neurologic deficits, and improved cognitive function in some domains at discharge and 30 days compared with controls.

Silent ischemic brain lesions after transcatheter aortic valve replacement: lesion distribution and predictors

Silent ischemic brain lesions and ischemic stroke are known complications of transcatheter aortic valve replacement (TAVR). We aimed to investigate the occurrence and distribution of TAVR-related silent ischemic brain lesions using diffusion-weighted magnetic resonance imaging (DWI). Consecutive patients with severe aortic valve stenosis treated with TAVR underwent cerebral DWI within 5 days after the index procedure. DWI scans were analyzed for the occurrence and distribution of new ischemic lesions post-TAVR. Forty-two patients were enrolled in this study. After TAVR, a total of 276 new cerebral ischemic lesions were detected in 38 (90 %) patients, with a median of 4.5 (interquartile range 2.0-7.0) lesions per patient. A total of 129 (47 %) lesions were detected in the cortical regions, 97 (35 %) in the subcortical regions, and 50 (18 %) in the cerebellum or brainstem. The median lesion volume was 20.2 µl (10.0, 42.7) and the total ischemic lesion volume was 132.3 µl (42.8, 336.9). The new ischemic brain lesions were clinically silent in 37 (97 %) patients; the other patient had a transient ischemic attack. Age (B = 0.528, p = 0.015), hyperlipidaemia (B = 5.809, p = 0.028) and post-dilatation of the implanted prosthesis (B = 7.196, p = 0.029) were independently associated with the number of post-TAVR cerebral DWI lesions. In addition, peak transaortic gradient was independently associated with post-procedural total infarct volume. Clinically silent cerebral infarcts occurred in 90 % of patients following TAVR, most of which were small (<20 μl) and located in the cortical regions of the cerebral hemispheres. An independent association was found between age, hyperlipidaemia and balloon post-dilatation and the number of post-TAVR ischemic brain lesions. Only peak transaortic gradient was independently associated with post-procedural total infarct volume.

Embrella embolic deflection device for cerebral protection during transcatheter aortic valve replacement

AimsTo compare the extent of cerebral ischemic injury after transcatheter aortic valve replacement (TAVR) with the use of an Embrella Embolic Deflector System versus unprotected TAVR. MethodsFifteen patients with severe symptomatic aortic stenosis underwent TAVR with use of the Embrella Embolic Deflector System for cerebral protection. Cerebral diffusion-weighted magnetic resonance imaging (DWI) was performed in all patients at day 4 after the procedure and images were retrospectively compared to 37 patients who had previously undergone TAVR without a protection device (TAVR-only group). ResultsSuccessful placement of the Embrella device was achieved in all patients. DWI revealed an increase in the number of ischemic lesions in the Embrella group compared with the TAVR-only group (9.0 vs 5.0, P = .044). The use of the Embrella device was however associated with a significant reduction in single-lesion volume: 9.7 μL [5.8, 18.4] versus 17.8 μL [9.5, 38.7] (P < .001). Moreover, total infarct volumes of more than 1000 μL were only seen in the TAVR-only group. More lesions occurred in the right side of the brain in the Embrella group, whereas in the TAVR-only group lesions were distributed equally between left and right. One patient in the TAVR-only group suffered from a transient ischemic attack. Postoperative evaluation was clinically uneventful in the Embrella group. ConclusionsThe use of the Embrella device during TAVR increased the number of cerebral ischemic lesions on postprocedural brain imaging. This increase in number was however accompanied by a significant reduction in single-lesion volume and the absence of large total infarct volumes.

Feasibility and exploratory efficacy evaluation of the Embrella Embolic Deflector system for the prevention of cerebral emboli in patients undergoing transcatheter aortic valve replacement: the PROTAVI-C pilot study.

This study sought to determine the feasibility, safety, and exploratory efficacy of the Embrella Embolic Deflector (EED) system (Edwards Lifesciences, Irvine, California) in patients undergoing transcatheter aortic valve replacement (TAVR). Few data exist on the value of using embolic protection devices during TAVR. This pilot study included 52 patients who underwent transfemoral TAVR. The EED system was used in 41patients, whereas 11 patients underwent TAVR without embolic protection (control group). Cerebral diffusion-weighted magnetic resonance imaging (DW-MRI) was performed at baseline and within 7 days and 30 days after TAVR. The EED system was successfully deployed at the level of the aortic arch in all patients with no complications. The deployment of the EED system was associated with high-intensity transient signals (HITS) as evaluated by transcranial Doppler (median: 48 [interquartile range: 17 to 198] HITS), and a higher total number of HITS was observed in the EED group (p< 0.001 vs. control group). DW-MRI performed within 7 days after TAVR showed the presence of new ischemic lesions in all patients in both groups, with a median number of 7 (interquartile range: 3 to 13) lesions per patient. The use of the EED system was associated with a lower lesion volume compared with the control group (p= 0.003). All new cerebral lesions had disappeared on the DW-MRI performed at 30 days after TAVR. Two strokes unrelated to the EED system occurred 2 and 29 days after TAVR. This study showed the feasibility and safety of using the EED system in TAVR procedures. The EED system did not prevent the occurrence of cerebral microemboli during TAVR or new transient ischemic lesions as evaluated by DW-MRI, but it was associated with a reduction in lesion volume. Further studies are warranted to determine the efficacy of using the EED system during TAVR procedures.

Silent Cerebral Ischemia After Thoracic Endovascular Aortic Repair: A Neuroimaging Study

The risk of clinically apparent, periprocedural stroke after thoracic endovascular aortic repair (TEVAR) due to dislodgement and embolization of aortic debris from intravascular manipulation of guidewires, catheters, and large-bore delivery systems ranges between 2% and 6% and has been associated with increased postoperative mortality. The rate of clinically silent cerebral ischemia is yet unknown, but may be even higher. Nineteen patients (13 male, 6 female) who underwent TEVAR were included into this descriptive study. Periprocedural apparent and silent cerebral ischemia was assessed by daily clinical neurologic assessment and serial cerebral diffusion-weighted magnetic resonance imaging (DW-MRI) at baseline and 5 days (median, interquartile range: 3.5) after the procedure. The TEVAR was successful in all patients without immediate clinically apparent neurologic deficits. Postinterventional cerebral DW-MRI detected a total of 29 new foci of restricted diffusion in 12 of 19 TEVAR patients (63%). Lesions were usually multiple (1 to 6 lesions per patient) and ranged in size between 15 mm3 and 300 mm3; 16 lesions were found in the left hemisphere, 13 lesions in the right hemisphere. Overstenting of the left subclavian artery was performed in 8 cases, but was not associated with lateralization of lesions. There were no additional apparent neurologic events during the in-hospital period. Thoracic endovascular aortic repair resulted in a high incidence of new foci of restricted diffusion on cerebral DW-MRI in a pattern suggestive of periprocedural embolization. Although multiple lesions per patients were found, these lesions were not associated with apparent neurologic deficits during the in-hospital period. Further developments in TEVAR should be directed toward reducing the risk of periprocedural cerebral embolization.