Mortality after mechanical thrombectomy in anterior circulation stroke may be higher at nighttime and on weekends

OBJECTIVES: The objective of this study was to compare clinical outcome and procedural differences of mechanical thrombectomy (MT) during on-call with regular operating hours. We particularly focused on dosimetric data which may serve as potential surrogates for patient outcome. METHODS: A total of 246 consecutive patients who underwent MT in acute anterior circulation stroke between November 2017 and March 2020 were retrospectively included. Patients treated (1) during standard operational hours (n = 102), (2) daytime on-call duty (n = 38) and (3) nighttime on-call duty (n = 106) were compared with respect to their pre-interventional status, procedural specifics, including dosimetrics (dose area product (DAP), fluoroscopy time and procedural time), and outcome. RESULTS: The collectives treated outside the regular operational hours showed an increased in-hospital mortality (standard operational hours 7% (7/102), daytime on-call duty 16% (6/38), nighttime on-call duty 20% (21/106), p = 0.02). Neither the dosimetric parameters nor baseline characteristics other procedural specifics and outcome parameters differed significantly between groups (p > 0.05 each). In most cases (> 90%), a successful reperfusion was achieved (TICI ≥ 2b). CONCLUSIONS: We found an increased in-hospital mortality in patients admitted at night and during weekends which was not explained by technical aspects of MT. KEY POINTS: • There is an increased mortality of stroke patients admitted at night and on weekends. • This is not explained by technical aspects of mechanical thrombectomy. • There were no statistical differences in the comparison of parameters linked to the radiation exposure, such as DAP, fluoroscopy time and procedure time.