CALCIFIED cerebral emboli may significantly reduce the effectiveness of endovascular thrombectomy (EVT) and lead to worse outcomes in patients with acute ischemic stroke, according to new findings. A retrospective single-center study spanning 2014 to 2021 identified key challenges when treating strokes caused by these rare, high-density emboli.
In the analysis of 1004 EVT cases, just 2.6% involved calcified cerebral emboli (CCEs). However, patients in this small subgroup experienced markedly inferior procedural and clinical outcomes compared with those who had strokes from noncalcified emboli (NCCEs).
Successful recanalization, defined as achieving a modified Thrombolysis in Cerebral Infarction (mTICI) score of at least 2b, occurred in only 62% of CCE cases—significantly lower than the 92% success rate seen in NCCE cases (p = 0.009). First-pass reperfusion was also notably compromised in patients with CCEs, with only 12% reaching this milestone compared to 46% in the noncalcified group (p = 0.006).
Beyond procedural success, the CCE group experienced more frequent and severe infarct growth. Eighty-one percent of CCE patients showed infarct progression, nearly double the rate observed in the NCCE group (42%; p = 0.004), with statistically significant severity differences (p = 0.005). These radiographic findings translated into poorer neurologic recovery: the median National Institutes of Health Stroke Scale (NIHSS) improvement was only 2 points in CCE patients compared with 5 points in NCCE counterparts (p = 0.008).
The authors suggest that the high density and rigidity of calcified emboli may hinder the ability of current thrombectomy tools to achieve effective clot retrieval, particularly during first-pass attempts. These limitations could explain the higher infarct growth and reduced neurological improvement observed in this cohort.
While CCEs remain a minority cause of large vessel occlusion strokes, their impact on EVT outcomes is disproportionately negative. The study highlights an urgent need for thrombectomy devices specifically optimized to address the unique mechanical challenges of calcified emboli.
As mechanical thrombectomy continues to evolve, recognition and targeted treatment strategies for these hard clots may play a pivotal role in improving stroke care outcomes for this underserved patient subgroup.
Reference:
Schacht H et al. Endovascular Thrombectomy for Acute Ischemic Stroke due to Calcified Cerebral Emboli. Stroke Res Treat. 2025;2025:5538938. doi:10.1155/srat/5538938. [Online ahead of print]
