The relationship between interventionists' experience and clinical and radiological outcome in intra-arterial treatment for acute ischemic stroke. A MR CLEAN pretrial survey.

BACKGROUND: Intra-arterial treatment in acute ischemic stroke is safe and effective as recently shown in several randomized clinical trials. The level of experience of the interventionist performing the IAT procedure has not been studied. The present study investigates effects of interventionists' experience on technical aspects of the procedure and clinical outcome of the patient. METHODS: In this study of 313 patients with a proximal intracranial arterial anterior circulation occlusion, treated in the Netherlands from 2002 until participation in the Multicenter Randomized Clinical trial of Endovascular treatment for acute ischemic stroke (MR CLEAN), data were collected retrospectively. The association of the senior interventionists' experience with duration of the procedure, adverse events, recanalization, neurological outcome, and functional outcome at discharge was analyzed. Multiple regression models adjusted for age, sex, stroke severity, carotid terminus occlusion, use of a retrievable stent and onset to door time were used. RESULTS: No association between interventionists' experience and recanalization, neurological outcome, or functional outcome was observed in a strict selection of patients. This strict selection include a start of intra-arterial treatment within 6h, no coagulation disturbances, systolic blood pressure<185mmHg and diastolic blood pressure<110mmHg), blood glucose level between 2.7 and 22.2mmol/L and the existence of a proximal intracranial occlusion. However, significant shorter procedure times were found with more experienced interventionists' [adjusted beta coefficient -0.67, 95% CI: -1.24 to -0.11], when using less strict inclusion criteria. CONCLUSION: No significant relation between the level of experience and either serious neurologic adverse events or poor outcomes was observed in this study of treatments by interventionists with experience of <50 previous procedures. We need further research to explore the relation of much higher levels of interventionists' and team experience with procedure times, results and patient outcomes.