Barriers to stroke treatment: The price of long-distance from thrombectomy centers

Abstract

Background: Endovascular thrombectomy, the preferred treatment for acute large-vessel occlusion stroke, is highly time-dependent. Many patients live far from thrombectomy centers due to large geographical variations in stroke services. This study aimed to explore the consequences of long transport distance on the proportion of thrombectomy-eligible patients who underwent thrombectomy, the clinical outcomes with or without thrombectomy, the timelines for patients transported, and the diagnostic accuracy of large-vessel occlusion in primary stroke centers.

Methods: We conducted a retrospective observational study in a county with only primary stroke centers, ∼ 300 km from the nearest thrombectomy center. All stroke patients admitted over a year were retrieved from the Norwegian Stroke Registry. A neuroradiologist identified all computed tomography images with large-vessel occlusions. A panel determined whether these patients had a corresponding clinical indication for thrombectomy.

Results: A total of 50% of the eligible patients did not receive thrombectomy. These patients had a significantly higher risk of severe disability or death compared to the patients who underwent thrombectomy. The median time from computed tomography imaging at the primary stroke center to arrival at the thrombectomy center was over 3 hours. Additionally, 30% of the large-vessel occlusions were initially undiagnosed, and half of these patients had a corresponding clinical indication for thrombectomy.

Conclusions: In a county with a long transport distance to a thrombectomy center, a high proportion of eligible patients did not undergo thrombectomy, negatively impacting clinical outcomes. The transport time was considerable. A high rate of large-vessel occlusions was initially not diagnosed.

Keywords: Thrombectomy; distance; large vessel occlusion; missed diagnosis; stroke units.

Figure 1.

Vascular findings and EVT for Agder County patients admitted with ischemic stroke in 2018. EVT: endovascular thrombectomy; LVO: large-vessel occlusion. A total of 30 patients were correctly diagnosed with LVO on initial assessment with a corresponding clinical EVT indication, 15 of these patients (50%) had EVT performed. A total of 20 of 67 patients (30%) had a missed LVO diagnosis on initial assessment.

Figure 2.

mRS score after 3 months. The mRS scores range from 0 to 6, with 0 indicating no symptoms, 1 no significant disability, 2 slight disability (unable to carry out all pre-stroke activities, but able to look after self without daily help), 3 moderate disability (requiring some help, but able to walk without assistance), 4 moderately severe disability (unable to walk or attend to bodily functions without assistance), 5 severe disability (bedridden, incontinent, requires continuous care), and 6 death. The number of patients with severe disability or death as clinical outcome (defined as mRS 5-6) was significantly higher for the patients with EVT not performed than with EVT performed (p = 0.020).

Figure 3.

Median time intervals for transported patients. First door: arrival at the primary stroke center; imaging: CT imaging at the primary stroke center; second door: arrival at the comprehensive stroke center; repeated imaging: MRI at the comprehensive stroke center; start EVT: arterial puncture before EVT, reperfusion: brain reperfusion after EVT. The median time intervals were 12 min from first door to imaging, 3 h and 3 min from imaging to second door, 19 min from second door to repeated imaging, 45 min from repeated imaging to start EVT, and 44 min from start EVT to reperfusion. Three patients went directly to EVT with no repeated imaging, see Supplemental Table S2 for details.