By Matthew E. Fink, MD
Louis and Gertrude Feil Professor and Chair, Department of Neurology, Associate Dean for Clinical Affairs, NewYork Presbyterian/Weill Cornell Medical College
Dr. Fink reports no financial relationships relevant to this field of study.
SOURCE: Katsanos AH, Malhotra K, Goyal N, et al. Intravenous thrombolysis prior to mechanical thrombectomy in large vessel occlusions. Ann Neurol 2019;86:395-406.
Since 2015, with the publication of five separate clinical trials demonstrating the benefit of mechanical thrombectomy, the standard of care for patients with large vessel occlusion (LVO) has been thrombectomy. There have been debates regarding the role of intravenous thrombolysis in LVO patients, with arguments that 1) it is better to treat all patients with intravenous thrombolysis regardless of whether they are candidates for mechanical thrombectomy, or 2) an LVO patient should go to directly to thrombectomy as soon as possible and skip the time it takes to administer intravenous thrombolytics. Underlying this argument is the fact that our ability to identify and diagnose patients with an LVO is far from perfect, and many such patients are found to have small vessel occlusion or distal occlusions that are not amenable to thrombectomy. Depriving a patient of thrombolysis deprives that person the opportunity to benefit from that treatment.
The authors of this study investigated the comparable safety and efficacy of bridging therapy with intravenous thrombolysis compared to direct mechanical thrombectomy in patients with acute ischemic stroke. They reviewed all available observational studies and analyses from randomized controlled trials that provided data on outcomes in patients stratified by intravenous thrombolysis treatment prior to mechanical thrombectomy. They identified 38 observational studies, resulting in evaluation of 11,790 LVO patients, of whom 56% were treated with bridging thrombolysis.
Compared to the patients treated with direct mechanical thrombectomy, bridging thrombolysis was associated with a higher likelihood of functional independence after three months (odds ratio [OR], 1.52), better functional improvement at three months as measured by a one-point decrease in the modified Rankin scale score (OR, 1.52), better early neurological improvement (OR, 1.21), successful recanalization (OR, 1.22), and successful recanalization with two or fewer device passes (OR, 2.28). Bridging therapy also was related to a lower likelihood of death at three months (OR, 0.64). The two groups did not differ significantly in the rate of symptomatic intracranial hemorrhage.
Bridging therapy with intravenous thrombolysis appears to be associated with improved functional outcome without any additional complications compared to direct mechanical thrombectomy for patients with acute ischemic stroke who have LVOs.