Understanding Atrial Fibrillation

A new guide to the mechanisms and principles behind the world’s most common abnormal heart rhythm

 Affecting 30 million or more people across the globe, atrial fibrillation is one of the most prevalent – and yet misapprehended – issues facing modern cardiology. Its potential causes and optimal treatment strategies are matters of some conjecture in the medical community, where ongoing research has yielded findings that can prove challenging to those not familiar with the complex physiology at the root of the condition. Recognizing these concerns, distinguished electrophysiologist Peter Spector has designed Understanding Atrial Fibrillation as a means by which to equip clinicians with the data and analytic tools needed to develop a better grasp of this arrhythmia’s full nature.   

The book begins by providing a detailed explanation of atrial fibrillation’s causal mechanisms and builds its exploration from there. Working toward an up-to-date knowledge of the mapping and ablation of atrial fibrillation, its chapters assess the experimental data that has shaped current thoughts on the condition and then outline the best methods with which to interpret that rich but potentially difficult information. This revelatory new guide:   

    Explores hypotheses of multiple drivers and mechanisms co-existing in individual patients
    Addresses common misperceptions and inaccurate views about atrial fibrillation
    Describes the basic physiology of atrial fibrillation’s propagation and reentry
    Explores the various mechanisms and higher-order dynamics of fibrillation
    Discusses how to intervene and alter atrial physiology to prevent fibrillation

Understanding Atrial Fibrillation is truly an invaluable resource for physicians, fellows, residents, electrophysiology lab staff, and all other practitioners involved in the diagnosis and treatment of atrial fibrillation.

contents

Preface ix

Acknowledgments xiii

Part I: Building blocks of fibrillation 1

Excitation and propagation 1

Source-sink relationships 2

What determines source-sink balance? 3

Propagation and reentry 4

Requirements for reentry 4

What makes a circuit? 6

Source-sink balance and rotors 6

Wave length 8

Wave length, path length, and reentry 9

Restitution 10

Initiating reentry 11

Part II: Atrial fibrillation mechanisms 21

The evolution of current concepts 21

The mass hypothesis of atrial fibrillation 30

Principles of propagation: Implications for fibrillation 32

Focal rotors 52

Micro‐reentry 55

Fibrillatory conduction or multi‐wavelet reentry? 66

Location of atrial fibrillation drivers 76

Principles of propagation: Driver interactions in fibrillation 87

Part III: Working with incomplete information 93

Cardiac mapping 93

Sample density and atrial fibrillation 115

What should we do with the patient who comes to the lab tomorrow? Putting it all together (without “it all”) 128

Putting it all together: Atrial fibrillation in three questions 132

Appendix A: Calculating probability in a random walk 135

Appendix B: Dominant frequency analysis 137

Appendix C: A stupid idea, but a learning opportunity 143

References 149

Index 161
Reviews

“This book on atrial fibrillation is a must-read for any physician  and/or investigator interested in studying the condition or caring for an AF patient. Dr. Spector takes a critical scientific approach to AF and its mechanisms. This book is a very welcome addition to the field.”

Hugh Calkins, MD, Professor of Medicine, Director of Electrophysiology, Johns Hopkins Medical Institutions, Baltimore, MD, USA

"Understanding Atrial Fibrillation is a gem. In less than 150 pages, I learned enough basic science about atrial fibrillation and its physiology to allow me to feel competent reviewing different approaches to its mapping and ablation. Peter Spector has an amazing knack for explaining complex physiology. This little book will be sit on the top of my bookshelf."

Kenneth A. Ellenbogen, MD, Kimmerling Professor of Cardiology, VCU School of Medicine, Richmond, VA, USA
“Dr. Spector frames atrial fibrillation as a compelling scientific mystery, his text flowing smoothly between sequences of questions and answers that read like detective story that one cannot put down.”
 
Omer Berenfeld, PhD, Professor of Internal Medicine, Professor of Biomedical Engineering, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI, USA.
“The excellent book Understanding Atrial Fibrillation by Dr. Peter Spector refreshingly explains atrial fibrillation as a scientific mystery; the text flows smoothly with sequences of questions and answers that read like a detective story that cannot be put down. From time to time, the reader is led to think that the culprit is found, only to discover in the following chapter that the evidence is not convincing enough and the investigation must continue. The book is a must-read for everyone, novice or expert, interested in developing a deeper understanding of atrial fibrillation.”
 
Omer Berenfeld, PhD, Professor of Internal Medicine, Professor of Biomedical Engineering, Center for Arrhythmia Research, University of Michigan, Ann Arbor, MI, USA