BACKGROUND The aim of this study was to assess the acute hemodynamic effects of remote ischemic preconditioning (RIPC) on coronary perfusion pressure and coronary collateral blood flow. METHODS A total of 17 patients with coronary heart disease with severe (70%-85%) stenosis in one or two vessels confirmed by angiography were enrolled into this study. They were randomly divided into the RIPC group (9 patients) and the control group (8 patients). Distal pressure of coronary artery stenosis before balloon dilation (non-occlusive pressure, Pn-occl) and distal coronary artery occlusive pressure (Poccl) during balloon dilation occlusion were measured in all patients. The patients in the RIPC group received three cycles of lower limb ischemia-reperfusion preconditioning (5 minutes inflation of a blood pressure cuff, followed by 5 minutes reperfusion). For controls, the cuff was not inflated. After this process, Pn-occl and Poccl were measured again in each patient. RESULTS There were no significant differences in angiographic characteristics between the two groups (all p > 0.05). Troponin I (TNI) levels after percutaneous coronary intervention (PCI) were lower in the RIPC group than in the control group (p = 0.004). In the RIPC group, mean Pn-occl and Poccl were significantly increased after RIPC compared to before RIPC [(72.78 ± 10.10) mmHg vs. (79.67 ± 9.79) mmHg, p = 0.002, (20.89 ± 8.61) mmHg vs. (26.78 ± 10.73) mmHg, p = 0.001, respectively]. CONCLUSIONS RIPC can improve distal coronary perfusion pressure and rapidly increase distal coronary occlusive pressure thereby improving coronary collateral blood flow.