A population-based incidence of acute large vessel occlusions and thrombectomy eligible patients indicates significant potential for growth of endovascular stroke therapy in the USA

Abstract

BackgroundData on large vessel strokes are important for resource allocation and infrastructure development.ObjectiveTo determine an annual incidence of large vessel occlusions (LVOs) and a thrombectomy eligible patient population.MethodsAll patients with acute ischemic stroke discharged over 3 years from a tertiary-level hospital serving a large geographic area were evaluated for an LVO (M1, internal carotid artery terminus, basilar artery). The incidence of LVO was determined for the hospital's 4-county primary service area (PSA, population 210 000) based on each county's discharges and extrapolated to the US population. ‘Thrombectomy eligibility’ for anterior circulation LVOs was based on time (onset <6 hours) and imaging (Alberta Stroke Program Early CT Score (ASPECTS) ≥6). The number of annual thrombectomy procedures was calculated for Medicare and private payer patients using federally available databases.Results1157 patients were discharged from the hospital's PSA, of whom 129 (11.1%, 95% CI 9.5% to 13.1%) had an LVO. This translated into an LVO incidence of 24 per 100 000 people per year (95% CI 20 to 28). 20 per 100 000 people per year had anterior circulation LVOs (95% CI 19 to 22), of whom 10/100 000/year (95% CI 8 to 11) were ‘thrombectomy eligible’. An additional 5/100 000/year (95% CI 3 to 6) presented with favorable ASPECTS after 6 hours of symptom onset. Basilar occlusion incidence was estimated at 4/100 000/year (95% CI 2 to 5). These rates yield 77 569 (95% CI 65 835 to 91 091) new LVOs per year in the USA. An estimated 10 284 mechanical thrombectomy procedures were performed in 2015.ConclusionsThis study estimates an LVO incidence of 24 per 100 000 person-years (95% CI 20 to 28). A current estimated annual thrombectomy rate of three procedures per 100 000 people indicates significant potential increase in the volume of endovascular procedures and the need to develop systems of care.

The Management of Acute Ischemic Strokes and the Prevalence of Large Vessel Occlusion in Left Ventricular Assist Device

“…Given the recently extended time window for endovascular therapy in acute stroke, the number of patients receiving treatment would perhaps increase as 2 patients in the late AIS group presented within an extended window but did not receive endovascular treatment [18]. The frequency of LVO in our study is comparable to the reported frequency of acute LVO from 11 to 46% in non-LVAD population [19][20][21]. The observation that nearly 1 in 3 persons had acute LVOs suggests that CTA study should be pursued and the endovascular therapy is feasible especially when the presence of acute LVO is known to carry a high mortality rate and poor functional outcome [21,22].…”

Prevalence of large vessel occlusion in patients presenting with acute ischemic stroke: a 10-year systematic review of the literature

“…Given an annual estimated incidence of 691 650 AISs per year in the USA,34 rates of LVO exceeding 20% would represent substantially greater numbers of potentially thrombectomy-eligible patients than what is reflected by current procedural volumes. In a study of patients with AIS, Rai et al used institutional data to compute an LVO rate of 11%, and population analyses to estimate a national incidence of 77 569 new LVOs each year 17. The authors subsequently emphasized that the disparity between current procedural volumes and these estimates reflected a potential 2–5-fold increase in annual thrombectomy volumes.…”

Prehospital stroke scale (FAST PLUS Test) predicts patients with intracranial large vessel occlusion

“…The real value of LVO prevalence is not yet precisely known; it ranges from 4.7% to 24% (Dozois et al., 2017; Rai et al., 2017). As PPV strongly depends on LVO prevalence, we provided expected PPV for populations with 10% and 20% LVO prevalence (Table 5).…”