Justin Davies is a Senior Reserch Fellow and Hononary Consultant Cardiologist at the National Heart and Lung Institute, Imperial College London. His main research interests include the development and application of pioneering technologies in engineering to aid understanding of disease mechanisms, and in the diagnosis of pathological disease states.
After completing his undergraduate training at Imperial College, he was awarded a prestigious British Heart Foundation research fellowship to undertake his PhD at Imperial College. Since then, he has trained in interventional cardiology with a specialist interest in physiological and structural assessment of coronary disease states. In 2008, he was appointed as a Walport Clinical Lecturer to support his research activities alongside his ongoing clinical commitments.
Through collaboration with Kim Parker and colleagues at institutions throughout the world, he has used mathematical modelling to aid understand of the mechanisms which lead to increased blood pressure which accompany ageing and pathological disease states. More recently Justin has developed coronary wave intensity as a tool to to assess the interaction between the coronary microcirculation and the aorta in the supply of blood to the heart.
In 2011 iFR (instantaneous wave-free ratio) was first described as a new technique for assessing the severity of a coronary stenosis using a pressure wire - without the need for administration of potent vasodilators. The results of the first-in-man study of the ADVISE (ADenosine Vasodilator Independent Stenosis Evaluation) were reported at TCT 2011, and subsequently ADVISE publication in Journal of American College of Cardiology (Sen S et al.). The original TCT slideset can be obtained here. Since then iFR has been evaluated in thoundsands of patients worldwide, and multiple publications have categorised its classification match with other measures of ischaemia.
Using gold standard invasive independent measures of ischaemia iFR has been found to have an identical diagnostic accuracy to FFR. More recent technological developments with Imperial Innovations have led to the commercialisation of iFR and iFR Scout/Pullback technologies. Find out more about iFR Wiki iFR.
Currently two large randomised clinical trials DEFINE-FLAIR and iFR SwedeHeart are being perfomed to compare iFR and FFR guided revascularisation. The results of these studies are expected in 2017. More can be found about the clinical trials for iFR iFR developments.
et al., 2017, Use of the Instantaneous Wave-free Ratio or Fractional Flow Reserve in PCI., N Engl J Med
et al., 2013, Diagnostic Classification of the Instantaneous Wave-Free Ratio Is Equivalent to Fractional Flow Reserve and Is Not Improved With Adenosine Administration, Journal of the American College of Cardiology, Vol:61, ISSN:0735-1097, Pages:1409-1420
et al., 2012, Improvement in Coronary Blood Flow Velocity With Acute Biventricular Pacing Is Predominantly Due to an Increase in a Diastolic Backward-Travelling Decompression (Suction) Wave, Circulation, Vol:126, ISSN:0009-7322, Pages:1334-+
et al., 2012, Attenuation of Wave Reflection by Wave Entrapment Creates a "Horizon Effect" in the Human Aorta, Hypertension, Vol:60, ISSN:0194-911X, Pages:778-+
et al., 2012, Development and Validation of a New Adenosine-Independent Index of Stenosis Severity From Coronary Wave-Intensity Analysis Results of the ADVISE (ADenosine Vasodilator Independent Stenosis Evaluation) Study, Journal of the American College of Cardiology, Vol:59, ISSN:0735-1097, Pages:1392-1402
et al., 2011, Arterial Pulse Wave Dynamics After Percutaneous Aortic Valve Replacement Fall in Coronary Diastolic Suction With Increasing Heart Rate as a Basis for Angina Symptoms in Aortic Stenosis, Circulation, Vol:124, ISSN:0009-7322, Pages:1565-1572
et al., 2006, Evidence of a dominant backward-propagating "suction" wave responsible for diastolic coronary filling in humans, attenuated in left ventricular hypertrophy, Circulation, Vol:113, ISSN:0009-7322, Pages:1768-1778
et al., 2008, Differences in cardiac microcirculatory wave patterns between the proximal left mainstem and proximal right coronary artery, American Journal of Physiology - Heart and Circulatory Physiology, Vol:295, ISSN:0363-6135, Pages:H1198-H1205
et al., 2006, Use of simultaneous pressure and velocity measurements to estimate arterial wave speed at a single site in humans, American Journal of Physiology - Heart and Circulatory Physiology, Vol:290, ISSN:0363-6135, Pages:H878-H885
et al., 2009, A Meta-Analysis of the Mechanism of Blood Pressure Change With Aging, Journal of the American College of Cardiology, Vol:54, ISSN:0735-1097, Pages:2087-2092
et al., 2008, What is the role of the aorta in directing coronary blood flow?, Heart, Vol:94, ISSN:1355-6037, Pages:1545-1547
et al., 2011, Association of Masked Hypertension and Left Ventricular Remodeling With the Hypertensive Response to Exercise, American Journal of Hypertension, Vol:24, ISSN:0895-7061, Pages:898-903
et al., 2010, A Surgeon's Eye View Noninvasively, Journal of the American College of Cardiology, Vol:56, ISSN:0735-1097, Pages:454-454
et al., 2010, Changes in the Central Arterial Pressure Pulse With Aging Reply, Journal of the American College of Cardiology, Vol:55, ISSN:0735-1097, Pages:2183-2184
et al., 2010, The arterial reservoir pressure increases with aging and is the major determinant of the aortic augmentation index, American Journal of Physiology - Heart and Circulatory Physiology, Vol:298, ISSN:0363-6135, Pages:H580-H586
et al., 2009, Differences in the Magnitude of Wave Reflection Account for Differential Effects of Amlodipine- Versus Atenolol-Based Regimens on Central Blood Pressure An Anglo-Scandinavian Cardiac Outcome Trial Substudy, Hypertension, Vol:54, ISSN:0194-911X, Pages:724-U73
et al., 2009, Augmentation Index, Left Ventricular Contractility, and Wave Reflection, Hypertension, Vol:54, ISSN:0194-911X, Pages:1099-1105
et al., 2009, Wave intensity analysis and the development of the reservoir-wave approach, Medical & Biological Engineering & Computing, Vol:47, ISSN:0140-0118, Pages:221-232