Comparing mismatch strategies for patients being considered for ischemic stroke tenecteplase trials

Currently there are multiple variations of imaging-based patient selection mismatch methods in ischemic stroke. In the present study, we sought to compare the two most common mismatch methods and identify if there were different effects on the outcome of a randomized clinical trial depending on the mismatch method used.

Investigate the effect of clinical and imaging-based mismatch criteria on patient outcomes of a pooled cohort from randomized trials of intravenous tenecteplase versus alteplase.

Baseline clinical and imaging scores were used to categorize patients as meeting either the DAWN mismatch (baseline NIHSS ≥ 10, and age cut-offs for ischemic core volume) or DEFUSE 2 mismatch criteria (mismatch volume > 15 mL, mismatch ratio > 1.8 and ischemic core < 70 mL). We then investigated whether tenecteplase-treated patients had favorable odds of less disability (on modified Rankin scale, mRS) compared to those treated with alteplase, for clinical and imaging mismatch, respectively.

From 146 pooled patients, 71 received alteplase and 75 received tenecteplase. The overall pooled group did not show improved patient outcomes when treated with tenecteplase (mRS 0-1 OR 1.77, 95% CI 0.89-3.51, p = 0.102) compared with alteplase. A total of 39 (27%) patients met both clinical and imaging mismatch criteria, 25 (17%) patients met only imaging criteria, 36 (25%) met only clinical mismatch criteria and, finally, 46 (31%) did not meet either of imaging or mismatch criteria. Patients treated with tenecteplase had more favorable outcomes when they met either imaging mismatch (mRS 0-1, OR 2.33, 95% CI 1.13-5.94, p = 0.032) or clinical mismatch criteria (mRS 0-1, OR 2.15, 95% CI 1.142, 8.732, p = 0.027) but with differing proportions.

Target mismatch selection was more inclusive and exhibited in a larger treatment effect between tenecteplase and alteplase.