Microembolization Is Associated With Transient Cognitive Decline in Patients Undergoing Carotid Interventions

Abstract

OBJECTIVE-Carotid interventions are important in helping to reduce the risk of stroke for patients with high-grade carotid artery stenosis; however, incidence of subclinical cerebral microemboli can occur during these procedures. Previously, associations have been found between incidence of microemboli and postoperative decline in memory. We therefore sought to determine whether this decline persisted long-term and to assess changes in other cognitive domains. METHODS-Patientswere prospectively recruited under an IRB-approved protocol at a single academic center. Neuropsychological testing was administered preoperatively and at 1 month and 6 month intervals postoperatively. Cognitive domains that were evaluated included verbal memory, visual memory, psychomotor speed, dexterity, and executive function. Diffusion weighted MRI (DWI) sequencing was performed preoperatively and within 48 hours postoperatively to identify procedure-related microemboli. Univariate and multivariate regression models were used to identify relationships between microembolization, demographics, and cognition.RESULTS-80 patients were included; all were male and average age was 69 years. Forty patients underwent CAS and 40 CEA. 45% were diabetic, 50% had CAD, and 41% had prior neurologic symptoms. 45 (56%) of the patients had new postoperative microemboli. Microembolization was significantly more common in the CAS cohort (P<.005). Univariate analysis demonstrated that patients with procedure-related embolization showed decline 1 month postoperatively in verbal memory and Trail Making A measures. Multivariate analysis demonstrated that procedure-related embolization (OR: 2.8, P=.04) and pre-op symptomatic stenosis (OR: 3.2, P=.026) were independently predictors of decline for the RAVLT Short Delay measure at 1 month; however, at 6 months there was no significant relationship between emboli

Causes and consequences of mesenteric embolization after endovascular aorto-iliac intervention — a nested case control study

“…All study patients who suffered from mesenteric embolization had undergone advanced time-consuming endovascular procedures, prior to the embolic event, where manipulation of numerous guidewires, sheaths, and stent grafts within atherosclerotic aorta and visceral arteries lined with a thrombus very likely contributed to this adverse outcome. In view of a recent report on carotid interventions where an alarming 85% of all endovascular carotid artery stenting procedures resulted in new microemboli [8], it seems probable that microembolization occurs much more often [9] after complex endovascular aorto-iliac procedures than the reported macroembolization rate of 1.8% in the present study.…”

“…Hence, the results of our study, and one previous study, suggest that smoking and renal insufficiency are, indeed, risk factors for mesenteric embolization after aortoiliac procedures [5]. Although diabetes was not found to increase the risk of mesenteric embolization in the present study, microembolism has been reported to be more likely in diabetics after carotid interventions [8].…”

Silent brain infarcts on diffusion-weighted imaging after carotid revascularisation: A surrogate outcome measure for procedural stroke? A systematic review and meta-analysis

“…Seventy-nine studies were excluded for the following reasons: MRI to detect cerebral ischaemia did not include DWI sequences, or DWI was not done in all patients (n = 15); 22–36 no DWI was performed before treatment (n = 11); 37–47 post-procedural DWI was performed more than seven days after treatment (n = 3); 48–50 the number of DWI+ patients or procedures could not be extracted (n = 6); 51–56 or information on procedural stroke was lacking or patients with procedural stroke were excluded from the analysis (n = 6). 49,57–68 One study was excluded because the analysis was restricted to patients with available six months’ follow-up who constituted less than half of the study population (n = 1). 69 One study was excluded since only pre-selected groups of patients showing micro-embolic signals in transcranial Doppler during CEA were included in the final analysis.…”

Carotid stenosis – basing treatment on individual patients’ needs. Optimal medical therapy alone or accompanied by stenting or endarterectomy

“…Hitchner et al observed a higher rate of new microemboli after CAS compared to CEA with a signifi cantly related cognitive decline at 30 days. Six months after intervention, an association between emboli and decline could no longer be demonstrated [47]. For CEA, CREST showed a signifi cantly increased rate of periprocedural MI and cranial nerve palsy (2.3 % and 4.7 % vs. 1.1 % and 0.3 % with CAS).…”