Rapid Intravenous Glyceryl Trinitrate in Ischemic Damage (RIGID): A potential neuroprotection strategy for acute ischemic stroke (AIS) patients

Despite advances in intravenous thrombolysis and endovascular thrombectomy, numerous acute ischemic stroke survivors continue to experience various disability levels. The nitric oxide (NO) donor, Glyceryl Trinitrate (GTN), has been identified as a potential neuroprotective agent against ischemic damage. We evaluated the safety and feasibility of intravenous GTN in AIS patients. Subsequently, we conducted a secondary analysis to assess for possible efficacy of GTN as a neuroprotectant. We conducted a prospective, double-blind, randomized controlled trial in the Stroke Intervention & Translational Center (SITC) in Beijing Luhe Hospital, Capital Medical University (ChiCTR2100046271). AIS patients within 24 h of stroke onset were evenly divided into GTN or control groups (n = 20 each). The GTN group received intravenous GTN (5 mg in 50 ml saline at a rate of 0.4 mg/h for 12.5 h/day over 2 days), while controls were administered an equivalent volume of 0.9% saline. Both groups followed standard Stroke Guidelines for treatment. Safety measures focused on SBP<110 mmHg and headache occurrence. Efficacy was assessed via the 90-day modified rankin score (mRS) and the national institutes of health stroke score (NIHSS). Of the 40 AIS patients, baseline characteristics such as age, gender, risk factors, and pre-mRS scores showed no significant difference between the groups. Safety measures of SBP<110 mmHg and headache occurrence were comparable. Overall, 90-day mRS (1 vs. 1) and NIHSS (1 vs. 1) did not significantly differ between groups. However, the GTN-treated group had a benefit in enhancing NIHSS recovery (triangle NIHSS 4.5 vs. 3, p = 0.028), indicating that GTN may augment recovery. Subgroup analyses revealed a benefit in the GTN group at the 90-day NIHSS score and triangle NIHSS follow up for non-thrombolysis patients (1 vs. 2, p = 0.016; 5 vs. 2, p = 0.001). Moreover, the GTN group may benefit mild stroke patients in NIHSS score at 90 day and triangle NIHSS observed at 90 days (1 vs. 1, p = 0.025; 3 vs. 2 p = 0.002). Overall, while preliminary data suggest GTN might aid recovery in NIHSS improvement, the evidence is tempered due to sample size limitations. The RIGID study confirms the safety and feasibility of intravenous GTN administration for AIS patients. Preliminary data also suggest that the GTN group may provide improvement in NIHSS recovery compared to the control group. Furthermore, a potential benefit for non-thrombolysis patients and those with mild stroke symptoms was identified, suggesting a possible potential role as a tailored intervention in specific AIS subgroups. Due to the limited sample size, further larger RCT will be necessary to replicate these results. Trial Registration www.chictr.org.cn, identifier: ChiCTR2100046271.