Physiological Assessment Of Coronary Stenoses And The Microcirculation

​Since the introduction of coronary angiography, a key technique in understanding coronary artery disease, a number of paradigms regarding its study and interpretation have taken place. Following an emphasis on improved angiographic and subsequent intracoronary imaging techniques, functional assessment of coronary circulation has demonstrated to have major implications for diagnosis and treatment of coronary artery disease. Fractional flow reserve, a pressure derived index of stenosis severity, constitutes the best example of the current importance of physiological assessment in clinical practice. However, the acceptance of FFR by cardiologists contrasts with important voids in knowledge on the basic principles of coronary physiology and of other available techniques that, as an alternative to FFR, allow a more comprehensive assessment of coronary circulation. This is particularly noticeable in the assessment of microcirculation, an unavoidable compartment of coronary circulation that is frequently affected in acute coronary syndromes of in the presence of cardiovascular risk factors or non-coronary heart disease. A deeper understanding of the relationship between epicardial vessel and microcirculatory involvement has started with the advent of newer imaging techniques like invasive optical coherence tomography, and non-invasive CT and NMR techniques. This book aims to be an indispensable tool for clinicians and researches in the field of coronary artery disease. It provides a balanced, comprehensive review of anatomy, physiology and available techniques, discusses both the diagnosis of epicardial vessel and microcirculatory disease, the impact of different diseases at different levels of coronary circulation, and the best way to address a separate or combined assessment of different levels of coronary circulation. ​

This book is open access under a CC BY 4.0 license. This quick-reference handbook offers a concise and practical review of key aspects of the treatment of ST-segment elevation myocardial infarction (STEMI) in the era of primary percutaneous coronary intervention (PPCI). In the context of STEMI, PPCI is the preferred mode of emergency revascularization. Access to PPCI is rapidly increasing and is now routinely practiced in both general and specialist hospitals and there has been a recent emphasis on developing STEMI networks to enhance and expedite the referral pathway. This coupled with concurrent developments to enhance the safety and efficacy of the PPCI procedure has heralded an era where STEMI interventions are increasingly considered an important subspecialty within interventional cardiology. Written by leading cardiologists who have been instrumental in the adoption of PPCI in their respective institutions, the book provides junior and senior cardiologists alike with insightful and thought-provoking tips and tricks to enhance the success of PPCI procedures, which may in turn translate into direct improvements in outcomes. The book is also relevant for healthcare providers and emergency department physicians.

In the past two decades a number of studies have shown that abnormalities in the function and structure of coronary microcirculation can be detected in several cardiovascular diseases. On the basis of the clinical setting in which it occurs, coronary microvascular dysfunction (CMD) can be classified into four types: CMD in the absence of any other cardiac disease; CMD in myocardial diseases; CMD in obstructive epicardial coronary artery disease; and iatrogenic CMD. In some instances CMD represents an epiphenomenon, whereas in others it represents an important marker of risk or may contribute to the pathogenesis of myocardial ischemia, thus becoming a possible therapeutic target. This book provides an update on coronary physiology and a systematic assessment of microvascular abnormalities in cardiovascular diseases, in the hope that it will assist clinicians in prevention, detection and management of CMD in their everyday activity.

Cardiologists must answer three important questions when evaluating and treating patients with a coronary artery stenosis. As a physiologist: "What is the effect of this stenosis on coronary blood flow and myocardial function?"; as a clinician: " Is this lesion responsible for the patient's symptoms?"; and finally as an interventionalist: "Will revascularization of this artery improve the patient?" Fundamentally, the answer to these questions can be given to a large extent by measuring coronary pressure. That is the rationale of writing this book. 1. 1 Historical overview. Andreas Gruentzig and most interventional cardiologists in the early days of PTCA, had the intuitive feeling that pressure measurements could help to establish the severity of a coronary stenosis and to monitor the progress and result of a coronary intervention. At that time, measuring coronary pressure by the balloon catheter was part of a standard procedure. A residual transstenotic gradient of less than 15 mmHg was generally considered as a good result. Later, however, it turned out that measuring these (resting) gradients with balloon catheters was inaccurate an only had a limited prognostic value. Moreover, because there was no consistent theory to correlate pressure measurements to blood flow, the interest in measuring coronary pressures faded and disappeared almost completely with the introduction of new balloon catheters not intended for pressure measurement.

Research centering on blood flow in the heart continues to hold an important position, especially since a better understanding of the subject may help reduce the incidence of coronary arterial disease and heart attacks. This book summarizes recent advances in the field; it is the product of fruitful cooperation among international scientists who met in Japan in May, 1990 to discuss the regulation of coronary blood flow.

Expert guidance from internationally recognized authorities, who provide clear and current updates on all aspects of interventional cardiology. This new edition; Contains a radically expanded chapter contents list presented in four clear sections; coronary interventions, interventional pharmacology, structural heart interventions, and endovascular therapy Includes 46 new chapters, including the latest advances in bioresorbable coronary stents, advanced transcatheter aortic valve replacement, MitraClip, new transcatheter mitral valve interventions, and more Chapters are templated for rapid referral, beginning with pathophysiological background and relevant pathology, moving to mechanisms of treatment, device description, procedural techniques, follow-up care, and ending with risks, contraindications and complications Multiple choice questions at the end of each chapter for self-assessment, a total of more than 400 MCQs in the book Features 19 procedural videos, hosted on a companion website

This book is intended as a guide for all cardiologists who are interested in coronary imaging and physiology, a sound understanding of which is vital for the optimal performance of appropriate coronary interventions. The basics of each relevant modality are presented, with clear explanation of clinical utility and evaluation of the evidence regarding clinical outcomes. All technical methods are described in detail, and the text is complemented by numerous helpful tables and illustrations. The effectiveness of intravascular coronary imaging in improving clinical outcomes is proven, and it is widely used for this purpose. Two modalities for intravascular coronary imaging are available in clinical practice: intravascular ultrasound (IVUS) and optical coherence tomography (OCT). For coronary physiology, the pressure wire-derived fractional flow reserve (FFR) provides information on the functional status of coronary trees. This technique and its clinical applications receive particular attention in the book, which also looks beyond FFR to FFR-CT, a method using computational fluid dynamics, and to invasive assessment of the microcirculation.

Although the technology required for the successful application of contrast echo cardiography has evolved rapidly over the past few years, the technique has not yet gained widespread clinical acceptance. One important reason for the lack of clinical acceptance is the relative complexity of the technique, particularly in respect to myocardial perfusion imaging. The interaction between micro bubbles and ultrasound is an entire field by itsel£ as is the coronary microvasculature. It is in this regard that practicing echocardiographers, cardiologists in training, radiologists, so no graphers, and students will find 'A Handbook of Contrast Echocardiography' particularly useful. Written by two leaders in the field who have presented illustrative cases not only from their own laboratories but also from others around the world, this volume is a lucid, concise, and practical guide for the day-to-day use of contrast echocardiography. Dr Peter Burns has been involved in almost all the technical advances in the imaging methods that have made it possible to detect opacification of the left ventricular cavity and myocardium from a venous injection of microbubbles. He has been responsible to a large degree for advancing our understanding of the interaction between micro bubbles and ultrasound, which he describes in clear and easy to understand terms in this book. Dr Harald Becher has been active in the clincal application of contrast echocardiography for several years and has gained considerable experience with many imaging techniques and microbubbles, which he describes in this volume in some detail.