Changing Paradigms of Periprocedural Antithrombotic Therapy in Neuroendovascular Therapy: Analysis of JR-NET 3

Bailout Technique for Coil Unraveling with a KUSABI Exchange Catheter: A Case Report

Objective

Coil unraveling is a rare, yet dangerous complication of endovascular coiling. In this study, we report a patient in whom an intraoperatively unraveled coil was successfully retrieved using a KUSABI exchange catheter, which is used in the field of cardiovascular medicine to facilitate catheter exchange in coronary interventions.

Case Presentation

The patient was a 90-year-old woman. To treat an unruptured aneurysm of the right internal carotid artery, endovascular coil embolization was performed. During the filling step, the coil started to unravel. Early attempts to retrieve the unraveled coil using a microsnare were complicated when the ensnared part broke off during the process. The broken tip of the unraveled coil was maneuvered inside the guiding catheter, after which a KUSABI catheter was inflated inside the guiding catheter to press and immobilize the unraveled coil against its inner lumen. This fragment of the unraveled coil was extricated from the patient by retracting the entire guiding catheter assembly. We guided a microsnare along the remaining unraveled coil to capture the intact part of the coil, and eventually retrieval was successful.

Conclusion

To our knowledge, no study has reported retrieval with a KUSABI trapping balloon catheter for the management of coil unraveling. However, this method is considered effective. We report this case and review the literature.

Endovascular Therapy for Acute Ischemic Stroke in Patients with Large-Vessel Occlusion due to Atherosclerotic Stenosis

OBJECTIVES

Endovascular therapy (EVT) is safe and effective for acute ischemic stroke (AIS) due to large-vessel occlusion (LVO). However, the influence of the AIS subtype (large-artery atherosclerosis [LAA] or cardioembolism [CE]) on clinical outcome in patients treated with EVT remains unclear. This study aimed to evaluate the differences in clinical results between the two subtypes using data from a multicenter prospective registry (RESCUE-Japan Registry 2).

MATERIALS AND METHODS

Among 2420 patients in RESCUE-Japan Registry, 682 patients who were diagnosed with LAA or CE were enrolled. The primary outcome was a modified Rankin Scale (mRS) score of 0-2 at 90 days. The secondary outcomes were 90-day mRS 0-1, 0-3, and 6. The relationship between time from onset and clinical outcome was also analyzed.

RESULTS

Among the 682 patients, 124 were classified into the LAA group and 558 into the CE group. The baseline National Institutes of Health Stroke Scale score was significantly lower (median 15 vs. 18, p < 0.001). At 90 days, mRS 0-2 was observed in 54 of 124 patients (44%) in the LAA group and 232 of 558 patients (42%) in the CE group (p = 0.69). The proportion of patients with mRS 0-2 tended to decrease according to onset-to-puncture time in the CE group but not in the LAA group (p_trend=0.0007).

CONCLUSIONS

The rate of good outcome was similar between LVO due to LAA and CE. However, the rate of favorable outcome did not decrease according to onset-to-puncture time in the LAA group.

Long-term complications after stent assist coiling dependent on clopidogrel response

BACKGROUND

Dual antiplatelet therapy (DAPT) is necessary for stent assisted coiling. However, long term use of DAPT has a potential risk of hemorrhagic events. We aimed to examine the relationship between clopidogrel reactivity and complications.

METHODS

Patients who underwent stent assisted coiling for unruptured aneurysms or previously treated aneurysms and received periprocedural DAPT in our institution between August 2011 to March 2020 were included. Platelet reactivity for clopidogrel was measured by VerifyNow assay system, and we defined the cut off value of P2Y12 Reaction Units (PRU) at 208 and classified patients as hypo-responders (PRU≧208) or responders (PRU<208). The rates of hemorrhagic and thrombotic events within 30 days (acute phase) and 30 days after the procedure (delayed phase) were compared between the two groups. Furthermore, changes in hemoglobin levels were measured before and after the procedure and at chronic stages (1 to 6 months thereafter).

RESULTS

From 61 patients included in this study, 36 patients were hypo-responders and 25 patients were responders. Hemorrhagic events occurred 8.0% only in responders in the acute phase (p = 0.16), and 2.78% in hypo-responders and 20.0% in responders in the delayed phase (p = 0.037). Changes in hemoglobin levels before and after the procedure were 1.22 g/dl in hypo-responders and 1.74 g/dl in responders (p = 0.032) while before the procedure and chronic stages they were 0.39 g/dl in hypo-responders and 1.39 g/dl in responders (p <  0.01). Thrombotic events were not significantly different between the two groups.

CONCLUSION

Long term use of DAPT after stent assisted coiling is related to hemorrhagic events in the delayed phase. Preventing for hemorrhagic events, the duration of DAPT should be carefully considered in clopidogrel responders.

Antiplatelet Loading Effects Prior to Endovascular Treatment: Carotid Artery Stenosis versus Unruptured Cerebral Aneurysms

Objective

Carotid artery stenosis and cerebral aneurism may have different platelet functions and antiplatelet responses because these diseases have different etiologies. In this study, we compared the antiplatelet loading effects prior to endovascular treatment between carotid artery stenosis and unruptured cerebral aneurysm (UCA) patients.

Methods

Nine patients with asymptomatic carotid artery stenosis (ACS), 14 with symptomatic carotid artery stenosis (SCS), and 20 with unruptured cerebral aneurysms were enrolled in this study. Antiplatelet (aspirin + clopidogrel) loading effects prior to endovascular treatment were evaluated using light transmission aggregometry and platelet aggregate detection methods.

Results

Although there are differences in the prevalence of atherosclerosis risk factors, maximum aggregation rates in light transmission aggregometry and platelet aggregation-prone properties were not different in the three disease groups.

Conclusion

Preoperative dual antiplatelet therapy with aspirin and clopidogrel may be appropriate for both carotid artery stenosis and cerebral aneurism patients even though their conditions and background factors differ.

A Case of Percutaneous Thrombectomy for Internal Carotid Artery Occlusion due to In-Stent Thrombosis Following Stent-Assisted Intra-Aneurysmal Embolization

Objective

In-stent thrombosis (IST) is a known complication after stent-assisted coil (SAC) embolization. We report a case of mechanical thrombectomy using a stent retriever (SR) for IST and share our experience with this treatment to prevent a poor outcome in future cases.

Case Presentation

The patient was a 62-year-old man. SAC embolization for an unruptured left internal carotid artery (ICA) aneurysm was performed. Three weeks after discharge, right hemiparesis and aphasia developed. Magnetic resonance imaging (MRI) demonstrated cerebral infarction in the left middle cerebral artery (MCA) territory and the left ICA was occluded. His relatives told us that the patient discontinued taking antiplatelet drugs. IST was diagnosed and emergency thrombectomy was performed. First, we tried to introduce an aspiration catheter or balloon catheter into the occluded lesion, but they were unable to be sufficiently inserted to the distal site. Therefore, we used a SR even though it carried a risk of friction on the deployed stent. The occluded artery was finally recanalized using the SR, but the stent became shortened. For the treatment strategy, sufficient medication (antithrombogenic agents and edaravone) should be administered first, followed by mechanical treatment. In mechanical treatment, thrombus fragmentation with a guidewire or balloon and aspiration should be attempted first. New aspiration catheters to carry the devices to the far distal site easily are now available.

Conclusion

SRs cannot be utilized for thrombectomy with a stent. In emergency situations, careful consideration during troubleshooting rather than using a SR is needed.