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

Abstract

<b>Objective: </b> 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. <b>Methods: </b> 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. <b>Results: </b> 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 &gt; 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], <i>p</i> = 0.004). In the whole sample, MetS was associated with mRS &gt; 2 (OR 2.4 [1.1–5.4], <i>p</i> = 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], <i>p</i> = 0.02). <b>Conclusion: </b> 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. <b>GLOSSARY: </b><b>AHA/NHLBI</b> = American Heart Association &amp; National Heart, Lung and Blood Institute; <b>BMI</b> = body mass index; <b>HDL</b> = high-density lipoprotein; <b>MCA</b> = middle cerebral artery; <b>MetS</b> = metabolic syndrome; <b>mRS</b> = modified Rankin scale; <b>NIHSS</b> = National Institutes of Health Stroke Scale; <b>TCD</b> = transcranial Doppler; <b>TIBI</b> = Thrombolysis in Brain Ischemia; <b>tPA</b> = tissue-type plasminogen activator.