Introduction Although stent-retrievers have revolutionized mechanical thrombectomy for acute large vessel occlusion (LVO), they can be associated with intimal injury and denudation from the mechanical scraping of the endothelium during retrieval. We hypothesized that allowing the retriever to dwell and intercalate with the thrombus would result in a lower number of needed passes for successful recanalization.

Methods Only the subset of patients treated for LVO with the overlapping split-type stent retriever and proximal balloon guide catheter protection was analyzed, excluding those treated with closed-cell retriever or large-bore suction thrombectomy. A mandatory dwell time was instituted after retriever deployment within the thrombus for a period of 9–10 min prior to guide balloon inflation and retriever withdrawal.

Results There were 76 consecutive patients treated using this method by the senior author from 2012 to 2017 with average age of 66.9 years (range: 27 to 91). The most common etiology was atrial fibrillation (AF), which was present in 44/76 patients (57.89%). Recanalization (TICI IIb/III) was obtained in 70/76 patients overall (92.11%). 42/44 patients with AF vs 28/32 with etiology other than AF achieved recanalization (95.45% vs 87.5%, p=n .s). Using the long-dwell technique, 39/44 AF patients were recanalized on first-pass compared to 19/32 other etiology patients (88.64% vs 59.4%, p<0.003). AF patients underwent a significantly lower number of stent-retriever passes per patient compared to non-AF LVO patients (1.16 vs 1.53 passes, p<0.014).

Conclusion Allowing the stent-retriever to intercalate with the occlusive large vessel embolus was found to be associated with a high rate of successful first-pass recanalization, especially in patients with AF. Although it needs to be balanced against the need for rapid flow restoration, a long-dwell time approach appears to help minimize the need for injurious multiple-pass intervention, with only a single pass needed in most cases of AF.

Disclosures A. Malek: 2; C; CereVasc LLC. 3; C; Stryker Neurovascular, Microvention-Terumo. 4; C; CereVasc LLC. M. Shutran: None.