Evaluating the effect of intracoronary N-acetylcysteine on myocardial reperfusion markers following primary percutaneous coronary intervention in patients with STEMI

Abstract

Purpose: Thrombolysis In Myocardial Infarction (TIMI) flow, Myocardial Blush Grade (MBG) and corrected Thrombolysis In Myocardial Infarction (TIMI) frame count (CTFC) are important prognostic indicators of myocardial reperfusion in patients with ST-segment-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). Recent studies suggest that high-dose N-acetylcystein (NAC), due to its antioxidant properties, may provide cardiac protection. The intracoronary administration of high dose NAC for the evaluation of its cardio-protective effects in human subjects has not been investigated. Methods: In a randomized double blind case controlled study, 100 consecutive patients with STEMI undergoing PCI were included. High dose NAC (100 mg/kg bolus followed by 10 mg/kg/hr intracoronary continued intravenously for 12 hours) was administered in the NAC group. Patients demographic data, ordered medications as well as pain to balloon time were documented in both groups. The difference in peak creatine kinase (CK-MB) concentration, high sensitive Troponin T (hs-TnT), TIMI flow, myocardial blush grade and CTFC were compared before and after PCI between those received NAC versus patients in control group. Results: One hundred patients with confirmed STEMI who underwent PCI were enrolled in the study. Patients had mean ± SD ages of 58.3±11.5 years old and 74% of them were male. There were not any significant differences between patients' baseline demographic or clinical characteristics in NAC versus control group. The difference between pain to balloon time was not significant between groups (p=0.202). Comparison of the difference in peak CK-MB was not significant as well (p=0.327). However, hs-TnT was reduced more in patients received NAC compared to those in control group (p=0.002). TIMI grade 3 flow was achieved in 70% of patients in NAC group compared to 48% of those in the control arm. These numbers were 16% vs. 6% for MBG of 3 and 80% vs. 64% for CTFC less than 23, respectively. Conclusion: According to the best of our knowledge, this was the first study conducted on high dose NAC administered intracoronary in STEMI patients with promising results. In this trial NAC could improve myocardial reperfusion markers and decrease its necrosis as revealed by the difference in peak levels of hs-TnT. Further studies are needed to elucidate the role of NAC in this population.