Original Article Peripheral microcirculatory hemodynamic changes in patients with myocardial ischemia Zehava Ovadia-Blechman a,b, *, Idit Avrahami c , Einat Weizman-Shammai b , Tali Sharir d , Michael Eldar b,e , Pierre Chouraqui f a Department of Medical Engineering, Afeka Tel Aviv Academic College of Engineering, 218 Bney-Efraim Rd., Tel Aviv, Israel b Neufeld Cardiac Research Institute, Tel Aviv University, Sheba Medical Center, Tel-Hashomer, Israel c Department of Mechanical Engineering and Mechatronics, Ariel University, Israel d Nuclear Cardiology Unit, Assuta Medical Centers, Israel e Heart Center, Sheba Medical Center, Tel Hashomer, Israel f Nuclear Medicine Institute, Hillel Yaffe Medical Center, Hadera, affiliated to the Rappaport Medical School, The Technion Israel Institute of Technology, Haifa, Israel 1. Introduction The development of new Cutaneous Blood Flow (CBF) measur- ing methods throughout the last decades runs concurrently with our understanding of physiological mechanisms of the microcir- culation. CBF and tissue oxygenation measurements play an important role in evaluating various conditions such as vasospasm, ischemia, injury and recovery processes and cutaneous implant function [1,2]. The ability to monitor non-invasively changes in the skin microcirculation level leads to improvements both in diagnosis and treatment of patients [3–7]. It was already shown that patients with coronary heart disease demonstrate changes in cutaneous microcirculation and a decrease in cutaneous blood mass [3,8–11]. One of the suggested predictors of risk for cardiovascular disease is Endothelial Function which is based on sensitivity to long-acting nitrates and vasoactive drugs. Studies have suggested that the noninvasive assessment of endothelial function may provide important information for individual patient risk, progress, and guidance of therapy [12– 18]. Therefore, there is a need to develop reliable non-invasive tools for assessment of myocardial ischemia, based on peripheral microcirculatory variables. At the Neufeld Cardiac Research Institute, our group has designed a combined noninvasive system that measures hemody- namic changes in the peripheral microcirculation (LPT system). Biomedicine & Pharmacotherapy 74 (2015) 83–88 A R T I C L E I N F O Article history: Received 30 June 2015 Accepted 20 July 2015 Keywords: Peripheral microcirculation Non-invasive measurement Myocardial ischemia A B S T R A C T Background: Patients with coronary heart disease demonstrate changes in skin microcirculation and a decrease in cutaneous blood mass. Objective: The goal of this study was to assess the feasibility of diagnosing myocardial ischemia based on peripheral microcirculatory variables. Methods: The skin microcirculatory measurements were monitored using an LPT system comprising a Laser Doppler Flowmeter (LDF), a photoplethysmograph (PPG) and a transcutaneous oxygen tension device (tc-PO 2 ). Concurrently, heart rate and blood pressure were monitored. Measurements were performed before and after exercise stress test. Subjects were divided into ischemic (20) and nonischemic (27) patients based on myocardial perfusion imaging (MPI). Results: The results indicate differences in LPT variables between ischemic and nonischemic patients following exercise, while no differences in the central variable values were observed between the two groups. Conclusions: Peripheral microcirculatory variables may be useful for non-invasive assessment of myocardial ischemia. The system has clinical potential for sensitive and noninvasive monitoring of vital variables during medical procedures in clinics, as well as in home care for patients who suffer from ischemic cardiac diseases. ß 2015 Elsevier Masson SAS. All rights reserved. * Corresponding author. E-mail address: zehava@afeka.ac.il (Z. Ovadia-Blechman). Available online at ScienceDirect www.sciencedirect.com http://dx.doi.org/10.1016/j.biopha.2015.07.011 0753-3322/ß 2015 Elsevier Masson SAS. All rights reserved.