ABSTRACT
Objectives: This study was designed to assess whether measurement of the index of microvascular resistance (IMR) before and following percutaneous coronary intervention (PCI) could help identify patients who develop periprocedural myocardial infarction (PPMI). Methods: 54 patients with stable coronary artery disease undergoing elective PCI were divided into PPMI group and no-PPMI group. IMR and FFR was measured before and following percutaneous coronary intervention (PCI) with a pressure wire. Times of balloon inflation was also analyzed. hs-TnI at 24 h post PCI was measured. rPIMR value was calculated. Results: IMR obtained at pre-PCI and post-PCI as well as rPIMR were significantly higher in PPMI patients than in no-PPMI patients (22.02±2.92 vs 17.46±3.44, 25.86±3.04 vs 18.96±2.84, 1.22±0.21 vs 0.94±0.24, all P<0.05, respectively). Patients with PPMI more frequently underwent pre- and post-dilatation(70.8% vs 36.7%, 54.2% vs 23.3%, P<0.05), respectively, the number of balloon inflations was significantly higher in patients with PPMI than in no-PPMI patients (4.33±1.79 vs 3.20±1.63, P<0.05). The area under the ROC curve for predicting PPMI event by pre-PCI IMR was 0.941 (95%CI: 0.884-0.998, P<0.05), cut-off value was 19.91 (sensitivity: 95.8% and specificity: 77.0%). Multivariate logistic analysis showed that pre- and post-PCI IMR, rPIMR were positively correlated with PPMI (all P<0.05). Conclusions: Measuring IMR and rPIMR may allow prospective identification of patients at increased risk of PPMI.