Impact of Provider Volume on Intraprocedural Rupture Risk During Endovascular Treatment of Ruptured Intracranial Aneurysms: A Systematic Review and Meta-Analysis.

Intraprocedural rupture (IPR) during coiling of ruptured intracranial aneurysms is a serious complication. In this study, we assessed whether center volume influences the risk of IPR. For this purpose, we conducted a systematic review (1996-present) including a final total of 98 studies. Centers were classified as high-volume (≥20 cases/year) or low-volume (<20), with the IPR rate as the primary outcome, and subgroup analyses by vascular territory and meta-regression were performed to quantify volume effects. The IPR rate was lower at high-volume centers than low-volume centers (3.5% [95% CI, 3.01-4.06] vs. 5.37% [95% CI, 4.06-7.07]; p < 0.01). Subgroup analyses by territory favored high-volume centers for anterior cerebral artery aneurysms (5.41% vs. 17.24%; p = 0.01) and middle cerebral artery aneurysms (7.49% vs. 50.0%; p < 0.01), while posterior circulation showed no significant difference (8.76% vs. 3.61%; p = 0.14). The meta-regression showed a statistically significant association in the overall IPR rate, with a regression coefficient of -0.65 (p = 0.0047). These findings potentially suggest a volume-outcome relationship, in which a higher annual case volume is associated with a lower risk of IPR during coiling of ruptured intracranial aneurysms.