Page 33 - ITPS-7-1

INNOSC Theranostics and
Pharmacological Sciences Antiplatelet treatments in neurological patients

femoral artery and is then threaded up to the affected artery complication when compared to adjunctive coiling such
with the aid of fluoroscopic guidance [51,52] . A microcatheter as SAC. Thromboembolic events are one of the most
is then inserted through the original catheter, delivering significant, yet frequent (up to 8.2% rate), complications
soft platinum metal coils into the aneurysm space . These that can potentially arise from CE therapy [44,65] . Given
[53]
initially straight-configured metal coils vary in sizes and, the significant risk for neurologic impairment and/or
after detachment from the microcatheter by means of death associated with thromboembolism, antiplatelet and
electrical induction, conform to various predetermined anticoagulant therapy is a major point of concern in the
circular shapes . Multiple coils may be deployed to therapeutic landscape of cerebral aneurysms. Moreover,
[51]
sufficiently fill the aneurysm compartment [54,55] . Short- ischemic event incidence in patients undergoing aneurysm
term success is indicated by coil-induced thrombus of the intervention can range from 10% to 40% when detected
post-operative space shown on immediate angiography, with diffusion-weighted imaging techniques (DWI) [66,67] .
resulting in an adequate seal from arterial blood flow . Thrombus formation can stem from a number of different
[56]
Coiling without stent assistance is distinct in that a intraoperative interactions between devices and pre-existing
[40]
stent is not placed in the arterial space either before or after aneurysm structure . Mechanisms include vessel injury, coil
coil deployment into the aneurysm [57,58] . Intravascular tent migration, existing thrombus dislodgement, and incomplete
[68]
assistance has been generally indicated based on aneurysm aneurysm obliteration with subsequent thrombosis .
neck size. More specifically, stent use for cases of wide- Intraoperative heparin loading is frequently utilized during
necked aneurysms has been shown to provide structural aneurysm coiling as a preventive measure against the
[69]
scaffolding support for coiling integrity and density within aforementioned thromboembolic complications .
the aneurysm sac . However, ongoing studies have been With regards to endovascular coiling pre-operative
[59]
aimed at establishing comparisons between coiling alone standard of care in patients with unruptured aneurysms,
and coiling with stent assistance based on criteria including antiplatelet therapy includes one dose of aspirin 81 or 325 mg
overall efficacy and safety in addition to solely anatomic either 1 day out from surgery or preoperatively on the same
parameters such as aneurysm diameter . Both Hong day. Of note, coiling alone does not necessarily indicate the
[60]
et al. and Phan et al. conducted separate meta-analyses administration of a second antiplatelet medication such
comparing the two aforementioned procedures with data as clopidogrel . However, an aspirin 100 mg/clopidogrel
[36]
analysis suggesting that SAC results in significantly higher 75 mg regimen may be recommended in some cases, more
progressive thrombosis rates and lower recurrent rates so when a stent is required . Complicated aneurysm
[40]
than coiling alone [61,62] . Conversely, immediate occlusion configuration requiring multiple catheters and challenging
rates and complications including hematoma, dissection, coiling may also indicate a pre-operative dual antiplatelet
perforation, stroke, and mortality were statistically regimen. Interestingly, Hwang et al. observed no significant
similar between the two pooled groups [61,62] . As expected, reduction in thromboembolism cases where only simple
mean aneurysm size was calculated to be slightly over coiling from a single microcatheter was needed . The
[43]
1 mm in the SAC cohort. Although both studies were evidence suggests antiplatelet therapy may or may not
based on retrospective cohort analysis, the evidence be critical to thromboembolic complication prophylaxis
leads way to current and future randomized controlled depending on the extent of coiling involvement. In addition
trials to determine if standard intracranial aneurysm to this finding, antiplatelet therapy was found to have no
treatment should shift toward SAC, particularly if this significant effect on hemorrhagic complications in cases of
option does not pose any significantly increased concern unruptured aneurysms . Combining these two findings, it
[43]
for complication. Endovascular coiling alone carries an appears that dual, and even single, antiplatelet therapy may
approximately 25% recanalization rate, but technological only have a beneficial effect on certain coiling procedures
advancements to coil properties have been made in an but administering either aspirin or an aspirin/clopidogrel
effort to reduce this trend . Variation of coils in terms combo as a pre-operative prophylactic measure renders no
[63]
of shape, size, malleability, material, and detachment sites apparent harm. Although other studies have found slight
allows providers to employ more effective thrombotic nonsignificant trends in hemorrhagic complications after
structures for each intracranial aneurysm case. Moreover, antiplatelet therapy, there is more evidence to suggest that
adjunctive devices and techniques to coiling alone have the potentially significant reductions in thromboembolism
been developed and extensively studied studied . outweigh the risks . Given the possibility for hemorrhagic
[64]
[70]
As previously mentioned, endovascular coiling of complications, a monotherapy dose of aspirin 81 mg or
cerebral aneurysms presents as a relatively conservative 325 mg shortly before coiling is generally a conservative
treatment option, particularly in cases of unruptured measure, whereas DAPT is reserved for more complicated
aneurysm. Similarly, coiling alone entails similar rates of cases not consistently characteristic of endovascular

Volume 7 Issue 1 (2024) 5 https://doi.org/10.36922/itps.1202