Intracranial Artery Calcifications Profile as a Predictor of Recanalization Failure in Endovascular Stroke Treatment

Abstract

Background: Acute ischemic stroke with large or medium-vessel occlusion associated with intracranial artery calcification (IAC) is an infrequent phenomenon presumably associated with intracranial atherosclerotic disease. We aimed to characterize IAC and its impact on endovascular treatment outcomes. Methods: We performed a retrospective cross-sectional study of consecutive patients with stroke treated with thrombectomy from January 2020 to July 2021 in our institution. We described IAC findings (length, density, and location pattern) on baseline noncontrast computed tomography. Patients were divided into 3 groups: IAC related to the occlusion location (symptomatic-IAC group), unrelated to the occlusion (asymptomatic-IAC group), and absence of any IAC (non-IAC group). We analyzed the association between the IAC profile and outcomes using logistic regression models. Intracranial angioplasty and stenting were considered rescue treatments. Results: Of the 393 patients included, 26 (6.6%) patients presented a symptomatic-IAC, 77 (19.6%) patients an asymptomatic-IAC, and in 290 (73.8%) patients no IAC was observed. The rate of failed recanalization (expanded Thrombolysis in Cerebral Infarction 0-2a) before rescue treatment was higher in symptomatic-IAC (65.4%) than in asymptomatic-IAC (15.6%; P <0.001) or non-IAC (13.4%; P <0.001). Rescue procedures were more frequently performed in symptomatic-IAC (26.9%) than in asymptomatic-IAC (1.3%; P <0.001) and non-IAC (4.1%; P <0.001). After adjusting for identifiable clinical and radiological confounders, symptomatic-IAC emerged as an independent predictor of failed recanalization (odds ratio, 11.89 [95% CI, 3.94–35.91]; P <0.001), adoption of rescue procedures (odds ratio, 12.38 [95% CI, 2.22–69.09]; P =0.004), and poor functional outcome (90-day modified Rankin Scale score ≥3; odds ratio, 3.51 [95% CI, 1.02–12.00]; P =0.046). Conclusions: The presence of IAC related to the occlusion location is associated with worse angiographic and functional outcomes. Therefore, identification of symptomatic-IAC on baseline imaging may guide optimal endovascular treatment strategy, predicting the need for intracranial stenting and angioplasty.

Development and internal-external validation of the ATHE Scale: predicting acute large vessel occlusion due to underlying intracranial atherosclerosis prior to endovascular treatment

“…In a review of 393 EVT patients, only 6.6% displayed symptomatic intracranial calcification that corresponded with the occlusion site. 35 This percentage drops to 5.3% when focusing on the anterior circulation. Even though calcification is more prevalent in ICAS-LVO than in EMB-LVO, its diagnostic reliability is still under scrutiny because of its low prevalence in EVT patients.…”

Clinico-radiological features of intracranial atherosclerosis-related large vessel occlusion prior to endovascular treatment

“…The potential benefit of EVT is limited by recanalization failure in a portion of stroke patients that ranges 15–30% 17 . Several factors may contribute to recanalization failure, including clot characteristics such as fibrin-rich or calcified clots, anatomical challenges, and atherosclerotic occlusions 12 , 18 , 19 . Currently, the diagnosis of ICAD-related occlusion based on The Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification requires a full diagnosis work-up, delaying the diagnosis after EVT is performed 20 .…”

“…This finding has been confirmed in other cohorts of patients with ICAS-LVO, where it is reported in 33% of cases 26 . Hence, symptomatic IAC are associated with unsuccessful reperfusion and could be used as an adjunct biomarker in the diagnosis of intracranial atherosclerotic disease in addition to other imaging features such as the presence intracranial atherosclerotic plaque on MRI or perfusion imaging maps patterns 12 . A preceding study showed that individuals with symptomatic IAC occlusion who underwent rescue procedures (intracranial angioplasty and/or stenting bailout) exhibited similar recanalization rate to that of individuals with non-calcified thrombus 12 .…”

“…Hence, symptomatic IAC are associated with unsuccessful reperfusion and could be used as an adjunct biomarker in the diagnosis of intracranial atherosclerotic disease in addition to other imaging features such as the presence intracranial atherosclerotic plaque on MRI or perfusion imaging maps patterns 12 . A preceding study showed that individuals with symptomatic IAC occlusion who underwent rescue procedures (intracranial angioplasty and/or stenting bailout) exhibited similar recanalization rate to that of individuals with non-calcified thrombus 12 . Hence, an early adoption of rescue procedures might lead to improved clinical and angiographic outcomes in patients with an ICAS-LVO in conjunction with IAC.…”

“…A symptomatic intracranial artery calcification (IAC) was defined as the presence of IAC with intimal pattern in the occlusion location or immediately proximal, in direct contact with the occlusion, as previously described 12 . Calcifications were registered on admission non-contrast CT with a slice thickness ≤ 1 mm and were considered for values > 130 HU, analogous to cardiology scoring systems 13 .…”