Atherosclerotic intracranial internal carotid artery calcification and intravenous thrombolytic therapy for acute ischemic stroke

Intracranial internal carotid artery calcification (IICAC) is a frequent and readily available finding in acute stroke patients treated with intravenous (IV) tissue plasminogen activator (tPA). We aimed to investigate the effects of IICAC subtype (medial and intimal) on the response to IV tPA.In this retrospective study, 91 (57% female, age 69 ± 13 years) consecutive acute anterior circulation stroke patients treated with IV tPA were included. IICAC were diagnosed and classified according to Kockelkoren's methods.IV tPA was effective at 24 h in 48% of patients with no IICAC (n = 27), 60% of intimal IICAC (n = 50) and 43% of medial IICAC (n = 14) (p=0.408). Presence of medial IICAC tended to be linked negatively to early dramatic response to IV tPA (p=0.052). IICAC status had no significant effect on the third month good (mRS≤2; 48% in no IICAC, 36% in intimal IICAC and 29% in medial IICAC; p=0.189) and favorable outcome (mRS≤1; 56% in no IICAC, 48% in intimal IICAC, 43% in medial IICAC, p=0.411). Frequency of symptomatic post-tPA cerebral hemorrhage was marginally higher in patients with non-intimal IICAC (21% vs. 4% in no-IICAC, 4% in intimal-IICAC, p=0.052). Exploratory multivariate analysis documented that this effect was stable (p=0.004) after adjustment for age, admission NIHSS and door-to-needle time.Medial type IICAC has been associated with numerical increase of symptomatic intracerebral hemorrhage and decrease of early dramatic response in stroke patients receiving IV tPA. Acknowledging that these preliminary observations should be replicated in larger cohorts, it is currently reasonable to say that "the treatment" is still useful in these patients and the presence of medial IICAC does not justify withholding IV tPA.