Dramatic Recovery During IV-TPA Infusion: Time Course and Clinical Pattern
Background: Dramatic recovery (DR) during TPA infusion is not well described. Methods: We compared clinical patterns and time course in patients with DR to Non-DR. We prospectively captured acute MCA strokes treated with standard NINDS IV-TPA protocols and performed serial NIHSS exams. DR was defined as a decrease by ≥ 10 NIHSS points or total score of ≤3 by end of TPA infusion.Intracranial flow signals were graded using the Thrombolysis in Brain Ischemia (TIBI) scale. Results: From 9/98–6/00, DR was observed in 12/53 patients(Table). With DR, there was a consistent pattern and time course of recovery: Gaze preference recovered first (8/11 complete; 2/11 partial; 1/11 none); followed by Sensory (4/7 complete; 3/7 partial recovery; 0/7 none) and Leg Strength (8/10 complete; 1/10 partial; 1/10 none). Arm Strength followed next, but was often incomplete (5/12 complete; 6/12 partial;1/12 none) Certain findings had partial improvement later during infusion: Facial strength (3/12 complete; 7/12 partial; 1/12 none);Aphasia (2/7 complete; 4/7 partial; 1/7 none). Dysarthria tended not to improve during infusion(2/7 complete; 0/7 partial; 5/7 none). DR was observed in 22% of patients during IV-TPA infusion and was sustained at 24 hours. The stroke severity and timing to bolus was similiar between DR and Non-DR groups. Early recanalization was the only noted difference. Conclusion: The clinical pattern of DR may result from reperfusion of the white matter tracts supplied by MCA perforators or improved collateral flow. With clot lysis, the observed recovery pattern is referable to vessel anatomy. How DR occurs and why some clinical deficits have delayed recovery needs further study.