982 Non Culprit Lesion in Acs Patients Discrepancy Between Hyperaemic and Resting Indexes

Abstract

Background Multivessel disease occurs in approximately half of patients presenting with STEMI and the best management non-culprit lesions is still unclear. The case reported a patient with inferior STEMI, in which the non-culprit lesion has been evaluated with a “full-physiology” approach by a pressure wire. Case Description A 52-year-old woman with a history of hypertension and diabetes was admitted to our center diagnosed with inferior STEMI. Coronary angiography showed a thrombotic occlusion (TIMI 0) of the right coronary artery (culprit lesion) and intermediate stenosis of proximal left anterior descending (LAD). Primary PCI (p-PCI) of the right coronary artery has been performed. After 4 days a stepwise complete physiological approach on the LAD artery has been performed. The physiological study showed a negative discrepancy between FFR - and RFR + with increased index of microvascular resistance (IMR). Discussion The fractional flow reserve (FFR) represents the best-known invasive method for the functional evaluation of intermediate coronary stenosis. Unlike the FFR, the resting flow ratio RFR is a non-hyperemic index that does not require the administration of a vasodilator such as adenosine as does the iwFR. There are many factors that can lead to a negative discrepancy between hyperemic and non-hyperemic indices. In the case presented, the functional values found were: FFR: 0.90 RFR: 0.86 and IMR = 76; CFR = 1.0. The FFR-/ RFR+ disagreement may reflect the attenuating influence of microvascular disease on adenosine-mediated vasodilation. Therefore, we decided to treat the LAD lesion according the RFR value with a DES 3.0×33 mm implantation. Conclusion Myocardial infarction can result in altered microvascular and endothelial dysfunction also in the non-culprit territory. The FFR - / RFR + disagreement may reflect the attenuating influence of microvascular disease on adenosine-mediated vasodilation.