There is a paucity of knowledge in the literature relating to the extent of clot burden
and stroke etiology. In this study, we measured the Extracted Clot Area (ECA) retrieved
during endovascular treatment (EVT) and investigated relationships with suspected
etiology, administration of intravenous thrombolysis and recanalization.As part of
the multi-institutional RESTORE registry, the ECA retrieved during mechanical thrombectomy
was quantified using ImageJ. The effect of stroke etiology (Large-artery atherosclerosis
(LAA), Cardioembolism, Cryptogenic and other) and recombinant tissue plasminogen activator
(rtPA) on ECA and recanalization outcome (mTICI) was assessed. Successful recanalization
was described as mTICI 2c-3.A total of 550 patients who underwent EVT with any clot
retrieved were included in the study. The ECA was significantly larger in the LAA
group compared to all other etiologies. The average ECA size of each etiology was;
LAA=109 mm2, Cardioembolic=52 mm2, Cryptogenic=47 mm2 and Other=52 mm2 (p=0.014*).
LAA patients also had a significantly poorer rate of successful recanalization (mTICI
2c-3) compared to all other etiologies (p=0.003*). The administration of tPA was associated
with a smaller ECA in both LAA (p=0.007*) and cardioembolic (p=0.035*) groups.The
ECA of LAA clots was double the size of all other etiologies and this is associated
with a lower rate of successful recanalization in LAA stroke subtype. rtPA administration
prior to thrombectomy was associated with reduced ECA in LAA and CE clots.
