Metabolic syndrome and resistance to IV thrombolysis in middle cerebral artery ischemic stroke

Abstract

The metabolic syndrome (MetS) is a cluster of vascular risk factors associated with a prothrombotic state. We aimed to evaluate the impact of MetS on the response to systemic tPA treatment in patients with acute middle cerebral artery (MCA) ischemic stroke. We studied 100 consecutive patients with ischemic stroke with MCA occlusions on prebolus transcranial Doppler (TCD) examination treated with tPA following SITS-MOST criteria. MetS was diagnosed following AHA/NHLBI-2005 criteria. Resistance to thrombolysis was defined as the absence of TCD-assessed complete MCA recanalization 24 hours after tPA infusion. Infarct volume was measured on CT scans. Long-term clinical outcome was evaluated by the modified Rankin scale (mRS) score at day 90. Fifty-eight (58%) patients fulfilled MetS criteria. Median prebolus NIH Stroke Scale score was 17. Forty (42%) patients showed resistance to clot dissolution, and 53 (53%) had poor clinical outcomes (mRS > 2). A multivariable-adjusted logistic regression model identified MetS as independently associated with resistance to thrombolysis (OR 4.7, 95% CI [1.7-13.6], p = 0.004). In the whole sample, MetS was associated with mRS > 2 (OR 2.4 [1.1-5.4], p = 0.03), although this association was no longer significant after multivariable adjustment. However, in patients with atherothrombotic stroke, MetS emerged as an independent predictor of poor long-term outcome (adjusted OR 13.9 [1.3-148.7], p = 0.02). In our series, the metabolic syndrome was associated with a poor response to thrombolysis in patients with acute middle cerebral artery occlusions, as reflected by a higher resistance to clot dissolution.