P2357Measurement of coronary artery compliance and stiffness index with novel application of optical coherence tomography in re-pressurised cadaveric coronary arteries

Abstract

Introduction and aim: Understanding the local factors which determine sites of disease progression and plaque rupture is key to refining decision making on coronary artery interventions. We have used high resolution optical coherence tomography (OCT) within repressurised cadaveric coronary arteries in intact hearts to measure the arterial compliance and stiffness index to determine the effect of atherosclerosis and calcification on these parameters. Method(s): OCT of differentially pressurised cadaveric coronary arteries was performed using coronary pressure wire and OCT system (St. Jude Medical Inc., Minnesota, USA) (Figure 1). A proprietary software (QCU CMS TM, Medis Medical Imaging System, Netherlands) was used to analyse the OCT data and to calculate cross sectional area for each frame and low and high pressure. Normalised compliance and stiffness index was calculated based on the pressure and area data. Ethical approval for this study was obtained from regional ethics committee. Result(s): Total of 3744 OCT frames (73 segments of 0.5 mm) from 16 coronary arteries of 9 different post-mortem subjects were analysed. The mean pressure different (DELTAP) was 21.6+/-15.3 mmHg between baseline and peak pressure state of the vessels. Atherosclerosis and calcification significantly affected local vascular compliance and stiffness (Table 1). Conclusion(s): This study has shown for the first time that coronary compliance varies locally depending on the extent of local coronary atherosclerosis and calcification which might effect disease progression. (Figure Presented).