A recent New York Times article re-surfaced the ‘debate’ regarding alteplase (IV-tPA) for ischemic stroke.1 There are some who continue to argue that the data for IV-tPA are not convincing. In this context, and otherwise, it is worthwhile to discuss a recent study comparing tenecteplase versus alteplase among patients with large vessel occlusion.2
In this study, 202 patients presenting within the IV-tPA treatment window of 4.5 hours and with an ischemic stroke due to large vessel occlusion were randomized to receive IV-tPA versus IV-tenecteplase prior to proceeding with mechanical thrombectomy. The main outcomes relevant for this discussion are the primary outcome of substantial reperfusion (restoration of blood flow in the affected area) and the safety outcome of brain hemorrhage.
Whereas 10% of patients who had received IV-tPA achieved substantial reperfusion prior to undergoing mechanical thrombectomy, 22% achieved substantial reperfusion in the tenecteplase group. The number of brain hemorrhages was the same in both groups (5-6%).
If confirmed, this represents a tremendous advance in thrombolysis because many patients require lengthy transport to reach a center where thrombectomy can be performed. Achieving reperfusion without increased risk of hemorrhage, potentially in the field using stroke ambulances and telemedicine, could dramatically improve population-level care for this otherwise very disabling form of stroke.
Further, these data suggest support the stability of the 6% estimate of brain hemorrhage risk with IV-thrombolysis. The observation that the hemorrhage risk (5 vs 6%) was the same regardless of reperfusion rate (10 vs 22%) is intriguing – if the two are independent, is the risk of hemorrhage from thrombolysis from something other than reperfusion? Further, the results of this study will spur additional study and we will thus have contemporary, high-quality data regarding the efficacy and safety of thrombolysis.
References
- https://www.nytimes.com/2018/03/26/health/stroke-clot-buster
- Campbell, et al. Tenecteplase versus Alteplase before Thrombectomy for Ischemic Stroke. NEJM. 2018:378:1573-82.
Neal S. Parikh, MD, earned his MD from Weill Cornell Medical College and completed residency training in neurology at the same institution. He is now an NIH T32 neuro-epidemiology and vascular neurology fellow at New York-Presbyterian Hospital/Columbia University Medical Center. He tweets @NealSParikhMD and contributes to Blogging Stroke as a blogger.