J Clin Neurol.  2017 Jan;13(1):32-37. 10.3988/jcn.2017.13.1.32.

Analysis of Risk Factors for Cerebral Microinfarcts after Carotid Endarterectomy and the Relevance of Delayed Cerebral Infarction

• Gwon JG
• Kwon TW
• Cho YP
• Kang DW
• Han Y
• Noh M

• KMID: 2364895
• DOI: http://doi.org/10.3988/jcn.2017.13.1.32

Abstract

BACKGROUND AND PURPOSE
Carotid endarterectomy (CEA) is performed to prevent cerebral infarction, but a common side effect is cerebral microinfarcts. This study aimed to identify the variables related to the production of microinfarcts during CEA as well as determine their association with delayed postoperative infarction.
METHODS
This was a retrospective review of data collected prospectively from 548 patients who underwent CEA. The clinical characteristics of the patients and the incidence rates and causes of microinfarcts were analyzed. Microinfarcts were diagnosed by diffusion-weighted magnetic resonance imaging. The presence of delayed postoperative infarction was compared between microinfarct-positive and microinfarct-negative groups.
RESULTS
In total, 76 (13.86%) patients were diagnosed with microinfarcts. Preoperative neurological symptoms were significantly related to the incidence of microinfarcts [odds ratio (OR)=2.93, 95% confidence interval (CI)=1.72-5.00, p<0.001]. Shunt insertion during CEA was the only significant procedure-related risk factor (OR=1.42, 95% CI=1.00-2.19, p=0.05). The presence of microinfarcts did not significantly increase the incidence of delayed postoperative infarction (p=0.204).
CONCLUSIONS
In the present study, risk factors for microinfarcts after CEA included preoperative symptoms and intraoperative shunt insertion. Microinfarcts were not associated with delayed postoperative infarction.

Keyword

carotid artery endarterectomy; microinfarcts; risk factor

MeSH Terms

Cerebral Infarction*
Endarterectomy, Carotid*
Humans
Incidence
Infarction
Magnetic Resonance Imaging
Prospective Studies
Retrospective Studies
Risk Factors*

Figure

• 

  Fig. 1 DW-MRI images of an 80-year-old female patient who underwent imaging 2 days after CEA. Multiple tiny foci that exhibit restricted diffusion (white arrows) represent microinfarct lesions. CEA: carotid endarterectomy, DW-MRI: diffusion-weighted magnetic resouance imaging.

• 

  Fig. 2 DW-MRI images obtained on postoperative day 2 showing microinfarcts in the middle cerebral artery and posterior cerebral artery border zone (white arrows), and DW-MRI images obtained 14 months postoperatively showing infarction in the middle cerebral artery territory (yellow arrow). DW-MRI: diffusion-weighted magnetic resonance imaging.

• 

  Fig. 3 Delayed postoperative infarction-free rate according to the follow-up period.

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