Functional Outcome After Mechanical Thrombectomy with or without Previous Thrombolysis

Abstract

Introduction

Combined intravenous therapy (IVT) and mechanical thrombectomy (MT) is the standard treatment for acute ischemic stroke (AIS) with large vessel occlusion (LVO). However, the use of  IVT before MT is recently being questioned.

Objectives

To compare patients treated with IVT before MT with those treated with MT alone, in a real-world scenario.

Methods

Retrospective analysis of AIS patients with LVO of the anterior circulation who underwent MT, with or without previous IVT, between 2016 and 2018.

Results

A total of 524 patients were included (347 submitted to IVT+MT; 177 to MT alone). No differences between groups were found except for a higher time from stroke onset to CT and to groin puncture in the MT group (297.5 min vs 115.0 min and 394.0 min vs 250.0 min respectively, p < 0.001). Multivariable analysis showed that age<75 years (OR 2.65, 95% CI 1.71–4.07, p < 0.001), not using antiplatelet therapy (OR 1.93, 95% CI 1.21–3.08, p = 0.006), low prestroke mRS (OR 4.33, 95% CI 1.89–9.89, p < 0.001), initial NIHSS (OR 0.89, 95% CI 0.86–0.93, p < 0.001), absent cerebral edema (OR 7.83, 95% CI 3.31–18.51, p < 0.001), and mTICI 2b/3 (OR 4.56, 95% CI 2.17–9.59, p < 0.001) were independently associated with good outcome (mRS 0-2).

Conclusions

Our findings support the idea that IVT before MT does not influence prognosis, in a real-world setting.

Introduction

Mechanical thrombectomy (MT) has deeply changed the therapeutic approach to acute ischemic stroke in large vessel occlusions (LVO).1, 2, 3, 4, 5, 6 Combined therapy of intravenous rtPA and MT is currently the standard treatment for patients with LVO in acute ischemic stroke,⁷ however, in all clinical trials only highly selected patients were enrolled, with the great majority of cases in both arms treated with intravenous rtPA.

In a meta-analysis of several randomized trials, the effect of MT was not influenced by intravenous therapy (IVT), raising the question of whether IVT is beneficial in patients with large vessel occlusion.⁸

It is known that IVT has low effectiveness in the recanalization of large vessels.⁹ Additionally, other potential drawbacks of IVT before MT include delayed initiation of MT, major bleeding, neurotoxicity, and disruption of the blood–brain barrier.10, 11, 12 Nevertheless, administration of IVT can have advantages. Tissue plasminogen activator promotes the breakdown of fibrin polymers. This way, it could favor the success of MT, not only by softening and reducing the clot size, but also by lysing possible distal small emboli and improving overall microvascular reperfusion, optimizing cerebral perfusion distal to the occlusion.^12,13

Our main goal was to evaluate if patients treated with IVT before MT had a better functional outcome at 90 days after stroke than those treated with MT alone in a real-world scenario. Moreover, we aimed to evaluate if other variables such as age, baseline functional status, neurologic deficits and recanalization rates influence the functional outcome.