RT Journal Article SR Electronic T1 HydroCoils Reduce Recurrence Rates in Recently Ruptured Medium-Sized Intracranial Aneurysms: A Subgroup Analysis of the HELPS Trial JF American Journal of Neuroradiology JO Am. J. Neuroradiol. FD American Society of Neuroradiology SP 1136 OP 1141 DO 10.3174/ajnr.A4266 VO 36 IS 6 A1 W. Brinjikji A1 P.M. White A1 H. Nahser A1 J. Wardlaw A1 R. Sellar A1 H.J. Cloft A1 D.F. Kallmes YR 2015 UL http://www.ajnr.org/content/36/6/1136.abstract AB BACKGROUND AND PURPOSE: The HydroCoil Endovascular Aneurysm Occlusion and Packing Study (HELPS) was a randomized, controlled trial comparing HydroCoils with bare-platinum coils. The purpose of this study was to perform a subgroup analysis of angiographic and clinical outcomes of medium-sized aneurysms in the HELPS trial.MATERIALS AND METHODS: Patients with medium-sized aneurysms (5–9.9 mm) were selected from the HELPS trial. Outcomes compared between the HydroCoil and bare-platinum groups included the following: 1) any recurrence, 2) major recurrence, 3) retreatment, and 4) mRS score of ≤2. Subgroup analysis by rupture status was performed. Multivariate logistic regression analysis adjusting for aneurysm neck size, shape, use of adjunctive device, and rupture status was performed.RESULTS: Two hundred eighty-eight patients with medium-sized aneurysms were randomized (144 in each group). At 15–18 months posttreatment, the major recurrence rate was significantly lower in the HydroCoil group than in controls (18.6% versus 30.8%, P = .03, respectively). For patients with recently ruptured aneurysms, the major recurrence rate was significantly lower for the HydroCoil group than for controls (20.3% versus 47.5%, P = .003), while rates were similar between groups for unruptured aneurysms (16.7% versus 14.8%, P = .80). Multivariate analysis of patients with recently ruptured aneurysms demonstrated a lower odds of major recurrence with HydroCoils (OR = 0.27; 95% CI, 0.12–0.58; P = .0007). No difference in retreatment rates or mRS of ≤2 was seen between groups.CONCLUSIONS: HydroCoils were associated with statistically significant and clinically relevant lower rates of major recurrence for recently ruptured, medium-sized aneurysms in the HELPS trial. Because this was not a prespecified subgroup analysis, these results should not alter clinical practice but, rather, provide insight into the design of future clinical trials comparing bare platinum with second-generation coils.HELPSHydroCoil Endovascular Aneurysm Occlusion and Packing Study