Too good to intervene? Thrombectomy for large vessel occlusion strokes with minimal symptoms: an intention-to-treat analysis

Abstract

IntroductionThe minimal stroke severity justifying endovascular intervention remains elusive; however, a significant proportion of patients presenting with large vessel occlusion (LVO) and mild symptoms subsequently decline and face poor outcomes.ObjectiveTo evaluate our experience with these patients by comparing best medical therapy with thrombectomy in an intention-to-treat analysis.MethodsAnalysis of prospectively collected data of all consecutive patients with National Institutes of Health Stroke Scale (NIHSS) score ≤5, LVO on CT angiography, and baseline modified Rankin Scale (mRS) score 0–2 from November 2014 to May 2016. After careful discussion with patients/family, a decision to pursue medical or interventional therapy was made. Deterioration (development of aphasia, neglect, and/or significant weakness) triggered reconsideration of thrombectomy. The primary outcome measure was NIHSS shift (discharge NIHSS score minus admission NIHSS score).ResultsOf the 32 patients qualifying for the study, 22 (69%) were primarily treated with medical therapy and 10 (31%) intervention. Baseline characteristics were comparable. Nine (41%) medically treated patients had subsequent deterioration requiring thrombectomy. Median time from arrival to deterioration was 5.2 hours (2.0–25.0). Successful reperfusion (modified Treatment in Cerebral Infarction 2b−3) was achieved in all 19 thrombectomy patients. The NIHSS shift significantly favored thrombectomy (−2.5 vs 0; p<0.01). The median NIHSS score at discharge was low with both thrombectomy (1 (0–3)) and medical therapy (2 (0.5–4.5)). 90-Day mRS 0–2 rates were 100% and 77%, respectively (p=0.15). Multivariable linear regression indicated that thrombectomy was independently associated with a beneficial NIHSS shift (unstandardized β −4.2 (95% CI −8.2 to −0.1); p=0.04).ConclusionsThrombectomy led to a shift towards a lower NIHSS in patients with LVO presenting with minimal stroke symptoms. Despite the overall perception that this condition is benign, nearly a quarter of patients primarily treated with medical therapy did not achieve independence at 90 days.

Clinical and Imaging Outcomes of Endovascular Therapy in Patients with Acute Large Vessel Occlusion Stroke and Mild Clinical Symptoms

“…These findings complement our prior pilot prospective intention-to-treat analysis of thrombectomy versus medical management for patients with an NIHSS score ≤5, which found a statistically significant discharge NIHSS score shift favoring ET-managed patients (-2.5 vs. 0, p = 0.01) and numerically higher rates of good outcomes [15]. …”

“…While historically thought to be a relatively benign condition, more recent data have shown that even these putatively minor strokes, if untreated, lead to higher rates of early neurologic decline, requiring rescue thrombectomy in up to 40% of patients, as well as lower rates of favorable clinical outcomes and independence, compared to patients receiving thrombolysis, ET, or both, with the greatest trend towards poor outcomes amongst untreated patients with an NIHSS score of 5-7 [5,8,15,17]. …”

Is Reperfusion Useful in Ischaemic Stroke Patients Presenting with a Low National Institutes of Health Stroke Scale and a Proximal Large Vessel Occlusion of the Anterior Circulation?

“…The main limitation is the absence of a control group undergoing optimal medical management. A recent small case-control study suggested that MT may lead to a shift towards a lower NIHSS at discharge than due to medical management alone [29]. These data, focusing on MT in minor-to-mild AIS patients, point to the importance of conducting future randomized studies comparing optimal medical management alone to optimal medical management combined with MT in this subgroup of patients.…”

The FAST-ED App: A Smartphone Platform for the Field Triage of Patients With Stroke

“…Indeed, whether patients with LVOS presenting with low NIHSS benefit from ET remains controversial. 1,19 Moreover, LVOS patients with lower clinical severities theoretically have better collateral flow, which is associated with better natural history, higher chances of response to IVT, and potentially a longer treatment window for ET. 20 As such, it is reasonable if not more logical that most patients with LVOS and low NIHSS would be first evaluated at a closer PSC/ ASRH to be assessed for IVT and undergo neurovascular imaging before the transportation to a more distant CSC.…”