Effect of remote ischemic Pre-conditioning on primary percutaneous coronary intervention outcomes: a randomized clinical trial

Background: Remote ischemic preconditioning (RIPC) is a simple non-invasive method by using cycles of ischemia and reperfusion on a remote organ. Objective: To determine the effect of RIPC outcomes in patients with ST-segment-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). Methods: This double blind randomized clinical trial was conducted in two teaching and reference hospitals in Mashhad, Iran. Sixty patients with acute STEMI were enrolled from October 2018 to January 2019. The patients were allocated into two groups, by using sealed envelope randomization i.e., a study group of patients who had undergone RIPC intervention and a control group of patients who had not undergone RIPC. Half an hour before PPCI, a sphygmomanometer cuff was placed around the left upper arm and inflated up to 200mmHg for five minutes; then the cuff was deflated for another five minutes, and this cycle was repeated 3 times before or during PPCI. Corrected Thrombolysis in Myocardial Infarction (TIMI) frame count, ST-segment resolution, reperfusion arrhythmias and contrast induced nephropathy (CIN) were evaluated in both groups after PPCI. Study data was analyzed by SPSS version 16. Results: A total number of 26 males and 14 females were studied in study groups (n=20 for each). Both groups were homogenous according to their baseline characteristics. Both TIMI grade and Corrected Thrombolysis in Myocardial Infarction Frame Count CTFC significantly improved after RIPC (p=0.001 and p<0.0001 respectively). Moreover, CIN and reperfusion arrhythmias were reduced in the intervention group (p=0.028 and p=0.016 respectively). Also, ST-segment resolution was significantly different among groups (p=0.002). After adjusting for baseline factors only a significant relationship was observed between performing intervention and final TIMI grade (OR=26.416, 95% CI for OR=1. 063, 656.184, p=0.046). Conclusion: RIPC can effectively reduce CIN and reperfusion arrhythmias in patients undergoing PPCI. Also, RIPC improved ST segment resolution and TIMI flow grade, and corrected TIMI frame count. Based on our results, RIPC may have a protective effect of on PPCI outcomes. Trial registration: The trial was registered at the Iranian Clinical Trial Registry (IRCT) (http://www.irct.ir) with the IRCT identification number IRCT20150614022713N2.