PMC9610214_01
(a) Diffusion-weighted magnetic resonance (MR) imaging of the brain at admission showing a newly onset cerebral infarction in the right putamen. (b) MR angiography showing occlusion of the right internal carotid artery (ICA) and severe stenosis of the left ICA at its cervical portion. (c) T1- weighted black blood MR imaging at the neck showing bright signal at the cervical portion of the left ICA. The plaque/muscle ratio was 3.39. (d-i) Preprocedural single-photon emission computed tomography (SPECT) using N-isopropyl-p-(123I) iodoamphetamine (123I-IMP) at resting state (d and g), after an acetazolamide challenge (e and h), and illustrations of cerebrovascular reactivity (CVR) using a color scale (f and i). The upper row indicates the centrum semiovale level and the lower row indicates the basal ganglia level. SPECT at resting state shows a decrease in cerebral blood flow (CBF) in the bilateral cerebral hemispheres (22-29 mL/100 g/min). SPECT after an acetazolamide challenge showing an insufficient increase of CBF, illustrations of CVR showing its extensive decline (7-26%), especially in the territories of the anterior cerebral artery and the superior branch of the middle cerebral artery in the bilateral cerebral hemispheres.
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Diffusion-weighted magnetic resonance imaging of the brain revealed a new-onset cerebral infarction of the right putamen [Figure 1a]. MR angiography showed total occlusion of the right internal carotid artery (ICA) and severe stenosis of the left ICA at its cervical portion [Figure 1b]. T1-weighted black blood MR imaging of the neck showed a markedly bright and massive plaque at the proximal portion of the left ICA with a very high plaque/muscle ratio (3.39), suggestive of its vulnerability [Figure 1c]. Single-photon emission computed tomography (SPECT) using N-isopropyl-p-[123I] iodoamphetamine (123I-IMP) at a resting state and after an acetazolamide challenge revealed extensive declines in cerebral blood flow (CBF; 22-29 mL/100g/min) and cerebrovascular reactivity (CVR; 7-26%) within bilateral ICA territories [Figures 1d-i].
(a and c) Left common carotid artery angiograms at the neck level (left anterior oblique view) before (a) and after (c) the first-stage angioplasty (b): Intraprocedural fluoroscopy of the first-stage angioplasty. Severe stenosis of the left ICA at its cervical portion with delayed opacification of the portion just distal to the stenosis being improved after angioplasty. (d and e) Left common carotid artery angiograms at the intracranial level (anteroposterior views) before (d) and after (e) the first-stage angioplasty. Opacification of territories fed by the left ICA including the right anterior cerebral artery becoming faster and clearer.
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INTEC, Aichi, Japan) into the left common carotid artery (CCA) through a right radial artery approach [Figure 2a]. We performed four total angioplasties by Sterling balloon catheter (Boston Scientific, Natick, MA, USA), measuring 3.0 mm x 40 mm and 3.5 mm x 40 mm, because the stenotic lesion could not be sufficiently dilated under distal filter protection using the Filterwire EZ (Boston Scientific, Natick, MA, USA) [Figure 2b]. The minimal lumen diameter (MLD) was doubled from 0.3 mm to 0.6 mm [Figures 2a and c]. The opacification of territories fed by the left ICA, including the right anterior cerebral artery, became faster and clearer than on the pretreatment angiogram [Figures 2de].
SPECT using 123I-IMP at a resting state before (a) and on the day after the first-stage angioplasty (b) showing a slight increase in CBF (approximately 5-10%) in both cerebral hemispheres and no apparent hyperperfusion.
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SPECT using 123I-IMP at a resting state on the day after the first-stage angioplasty revealed a slight increase in CBF (approximately 5-10%) in both cerebral hemispheres and no apparent hyperperfusion [Figures 3a and b].
(a) Intraprocedural fluoroscopy during transcatheter aortic valve implantation (TAVI) demonstrating the deployment of the valve device (white arrow). (b) Vital signs chart during general anesthesia for the TAVI procedure demonstrating a pronounced decrease of blood pressure during the steep increment of heart rate due to the rapid right ventricular pacing for deployment of the valve device (white arrow). The red bars and green lines represent the blood pressure and heart rate, respectively.
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TAVI was performed through the right femoral artery approach under general anesthesia [Figure 4a]. To perform TAVI under single antiplatelet therapy, clopidogrel and apixaban administration were, respectively, stopped 3 days before, and on the day of TAVI (we chose a 3-day clopidogrel discontinuation period because of the risk of cerebral ischemia despite the fact that it is recommended to be at least 5 days). The patient tolerated both hypotensions during general anesthesia and rapid right ventricular pacing (maximum 180 bpm, [Figure 4b]) during valve replacement and no periprocedural cerebrovascular events occurred.
(a and e) Left common carotid artery angiograms at the neck level (left anterior oblique view) before (a) after (e) the second-stage carotid artery stenting (CAS). (b-d) Intraprocedural fluoroscopies during predilatation (b), postdilatation (c), and immediately after CAS procedure (d and f). Diffusion-weighted MR imaging of the brain on the day after the second-stage CAS showing no newly onset, abnormal, and hyperintense lesion. (g) SPECT on the day after the second-stage CAS showing a mild increase (recovery) of CBF in the territories of the left anterior and middle cerebral arteries that did not meet the criteria for hyperperfusion phenomenon.
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The left carotid angiogram showed no apparent restenosis in the formerly angioplastied portion [Figure 5a]. Predilatation was conducted under distal filter protection using a Sterling balloon catheter, sized 3.0 mm x 40 mm [Figure 5b]. Monorail measuring 10 mm x 31 mm (Stryker, Kalamazoo, MI, USA) and postdilatation was performed using a Sterling balloon catheter measuring 4.5 mm x 30 mm [Figures 5c-e]. Mild hypotension occurred during postdilatation and was immediately resolved after balloon deflation. No apparent periprocedural complications, including ischemic stroke or CHS, were observed [Figures 5f and g].