Transient Contrast Encephalopathy After Carotid Artery Stenting

Transient cortical blindness, a rare complication during cerebral digital subtraction angiography: A case report and literature review

Transient cortical blindness (TCB) is a rare consequence of cerebral angiography with no recognized cause. TCB was observed in a patient with a wide‐neck cavernous aneurysm during digital subtraction angiography. One hour after angiography, vision returned spontaneously, with no neurological damage. An MRI was performed three hours after the incident and revealed no abnormalities.

A case of contrast-induced encephalopathy

The differential diagnosis of the patient with encephalopathy is broad and remains a common yet challenging problem for critical care physicians. A case is presented of contrast-induced encephalopathy in an 81-year-old man undergoing a left heart catheterisation after receiving iopamidol, a low-osmolar contrast agent. Immediately after receiving contrast, our patient experienced severe headache, agitation, altered mentation and significant skin hypersensitivity. This rare, acute and reversible neurological disturbance can be associated with administration of intra-arterial, osmotic, iodinated contrast. Although uncommon, it is important to recognise the various presentations, risk factors and treatment of this condition.

Adjunctive ultrasonography to minimize iodinated contrast administration during carotid artery stenting: a randomized trial

PURPOSE

To report a single-center, prospective randomized controlled trial that compared contrast use during ultrasound-assisted carotid artery stenting (CAS) to CAS procedures without ultrasound.

METHODS

Between August 2010 and November 2011, 22 patients (18 men; mean age 72.8 years, range 62-84) with 25 severe symptomatic (n=3) or asymptomatic (n=22) carotid stenoses undergoing an endovascular intervention were randomly allocated (~1.1) to ultrasonography-assisted (n=13) or stand-alone (n=12) CAS. The primary endpoints were contrast use and number of selective cerebral injections. Secondary endpoints were procedure time, fluoroscopy time, any stroke, renal function assessment, major adverse cardiac events (MACE), and death.

RESULTS

In the study period, 23 of 25 scheduled CAS procedures (12 ultrasound-assisted, 11 control) were completed in 20 patients; 2 procedures were aborted owing to friable plaque and difficult guidewire access, respectively. There were no deaths, stroke, MACE, or precipitation of dialysis-dependent renal failure in either group. Iodinated contrast usage was reduced by 61% (45.4±24.4 vs. 17.8±11.9 mL, p=0.002) and number of selective cerebral contrast injections by 49% (8.3 vs. 4.2, p=0.002). Neither time taken to complete the procedure (32.5 vs. 35.4 minutes, p=0.38) nor fluoroscopy time (14.5 vs. 13.9 minutes, p=0.54) differed significantly between the groups. Creatinine levels remained stable after CAS and did not differ between groups.

CONCLUSION

Ultrasonography-assisted CAS is feasible and safe. Its use can significantly lower the usage of iodinated contrast and the number of selective cerebral circulation injections while not prolonging the length of the procedure or the fluoroscopy time.

Safety and feasibility of intravascular optical coherence tomography using a nonocclusive technique to evaluate carotid plaques before and after stent deployment

PURPOSE

To evaluate the safety and feasibility of optical coherence tomography (OCT) in patients with carotid stenosis undergoing carotid artery stenting (CAS).

METHODS

In a prospective study, 25 consecutive patients (15 men; mean age 74±4 years) undergoing protected CAS were enrolled and underwent high-definition (homoaxial resolution 10 µm) OCT image acquisition before stent deployment, immediately after stent placement, and following postdilation of the stent (3 scans/patient). Pullbacks were started during a nonocclusive flush, mechanically injecting 24 mL of 50% diluted contrast at 6 mL/s to displace blood from the artery. Two independent physicians judged the quality of images on a predefined 1-10 scale. The proportions of specific agreement and kappa values (κ) were calculated.

RESULTS

No procedural or in-hospital neurological complications occurred (any stroke/death 0%). The technical success of OCT pullbacks was 97.3% (73/75). The total amount of contrast was 86±18 mL/patient. No significant alteration in glomerular filtration rate or any other significant adverse event occurred. The images obtained were of high quality (mean value 8.1 out of 10), with good inter- and intraobserver agreement (κ = 0.81-0.87 and κ = 0.95, respectively). OCT images revealed innovative features such as rupture of the fibrous cap, plaque prolapse, and stent malapposition in a high percentage of the patients (range 24%-100%).

CONCLUSION

Intravascular OCT during a nonocclusive flush appears to be feasible and safe in carotid arteries. Since some original and unexpected information after CAS has been made available for the first time at such a high definition, future studies with OCT should focus on the interaction between carotid plaque and stent design, which might revolutionize our understanding of the mechanisms of carotid stenting, as well as influence our clinical policies.

A case of contrast-induced encephalopathy using iodixanol

PURPOSE

To document a heretofore unreported complication of the contrast agent iodixanol during an endovascular procedure.

CASE REPORT

A 76-year-old woman with a history of coronary artery disease was admitted to the emergency department for recurrent transient ischemic attacks. Before combined percutaneous transluminal coronary angioplasty and carotid artery stenting (CAS) using iodixanol, the patient suffered from concomitant unstable angina and recurrent transient ischemic attacks. The total amount of iodixanol used during the CAS procedure was 300 mL. Contrast-induced encephalopathy, which manifested as aphasia, stupor, and full hemiparesis immediately after the combined procedure, was diagnosed by urgent computed tomography. Treatment was based on anti-edema drugs, and the patient made a complete recovery within 48 hours, without any neurological sequelae.

CONCLUSION

Although previously reported in relation to other types of contrast media, contrast-induced encephalopathy has never been described as a complication of an endovascular procedure using iodixanol.

Transient contrast encephalopathy after carotid angiography mimicking diffuse subarachnoid haemorrhage

Neurotoxicity caused by intraarterial injection of low-dose low osmolar, iodinated contrast agents during radiologic studies is an extremely rare adverse event. Contrast medium induced disruption of the blood-brain barrier and a direct neurotoxic effect by contrast media have been proposed as a potential mechanism of neurotoxicity. This report describes an unusual case of transient neurotoxicity following diagnostic angiography mimicking clinically and radiologically subarachnoid hemorrhage. The patient recovered without any intervention after 4 days of conservative treatment.

Classification for carotid artery stenting complications: manifestation, management, and prevention

Carotid artery stenting is a rapidly evolving method for treating carotid artery disease. Various intraprocedural and postprocedural complications have been reported in the literature. However, the absence of a unified classification scheme for these complications makes it difficult, if not impossible, to study their precise incidence, predictors, and management. The aim of this article is to propose the first joint classification of periprocedural complications, to analyze their incidence and etiology, and suggest possible ways to manage and prevent them. This classification is intended to be used as a common platform for prompt recognition, evaluation, treatment, and universal study of the complications during carotid stenting procedures. For this purpose, the opinions of the major experts on carotid interventions worldwide were merged with all the available information reported in the English-language literature to present as accurately as possible the management and prevention of carotid stenting complications according to this proposed classification.

History and current status of endovascular management for the extracranial carotid and supra-aortic vessels

Few procedures in the history of medicine have been more controversial than carotid artery stenting (CAS) for the management of carotid artery occlusive disease. Introduced just as the randomized trials were establishing carotid endarterectomy as the gold standard for carotid interventions, CAS has finally reached the point in its development when dedicated stenting systems are being tested in randomized clinical trials. Assisted by the concomitant use of distal protection devices, CAS has shown equipoise with endarterectomy in terms of safety at 30 days. This review summarizes the completed and ongoing CAS trials and the applications of endovascular techniques in the supra-aortic vessels.

Cerebral hyperperfusion after angioplasty and stenting of a totally occluded left subclavian artery: a case report

Cerebral hyperperfusion syndrome is documented after angioplasty of carotid and vertebral artery lesions. The authors report the first instance of cerebral hyperperfusion syndrome in the posterior cerebral circulation after angioplasty and stenting of a totally occluded left subclavian artery.