Atrial Fibrillation

ISBN-13: 9781447119005 / Angielski / Miękka / 2011 / 243 str.

John Rawles

Opis

Atrial fibrillation is a common and important arrythmia which affects nearly5% of peopple over 70. This synthesis of current knowledge which is based onmuch original work by the author brings togeher for the first time the many areas of advance in recent years and will help to make experts from the highly specialised fields within cardiology aware of the developments withinothers.

Spis treści

1 The Cardiac Conducting System and Its Autonomic Control.- Anatomy of the Conducting System.- Basic Cardiac Electrophysiology.- The Initiation and Propagation of the Cardiac Impulse.- Resetting the Sinoatrial Node Pacemaker.- The Spread of the Impulse Through the Atria.- The Functioning of the Atrioventricular Node.- Does the Atrioventricular Node Conduct?.- Autonomic Innervation of the Heart.- Autonomic Control of the Sinoatrial Node.- Autonomic Control of the Atrioventricular Node.- 2 The Pathophysiology of Atrial Fibrillation.- Pathology.- The Electrophysiology of Atrial Fibrillation.- Electrophysiological Factors that Predispose to Atrial Fibrillation.- Initiation of Atrial Fibrillation.- The Mapping of Atrial Flutter and Fibrillation: The Essential Distinction Between Them.- The Ventricular Response in Atrial Fibrillation.- The Input to the Atrioventricular Node.- The Ventricular Response in Atrial Fibrillation.- The Role of the Autonomic Nervous System in Atrial Fibrillation.- Autocorrelation and the Baroflex.- Fibrillatory Waves in Atrial Fibrillation.- The Brody Phenomenon in Atrial Fibrillation.- The QT Interval in Atrial Fibrillation.- Is the QT Interval in Atrial Fibrillation Different from that in Sinus Rhythm?.- Atrial Fibrillation and the Wolff-Parkinson-White Syndrome.- Aberration in Atrial Fibrillation.- 3 Models of the Atrioventricular Node.- The Electrophysiological Model of the Atrioventricular Node.- Analogue Models of the Atrioventricular Node.- Mathematical Models of the Atrioventricular Node in Atrial Fibrillation.- The Model of Cohen et al. (1983).- The Atrioventricular Node as a Biological Oscillator.- The Model of Guevara and Glass (1982).- Resetting the Oscillator.- The Response of a Sine-Wave Oscillator to a Rapid Random Input.- The Effect of a Refractory Period on the Behaviour of the Sine-Wave Model of the Atrioventricular Node.- What Values Should Be Assigned to the Sine-Wave Model’s Parameters?.- More Electrophysiological Phenomena: Ventricular Extrasystoles.- The “Compensatory Pause” in Atrial Fibrillation.- Peeling Back Refractoriness.- The Effect of Right Ventricular Pacing in Atrial Fibrillation.- The Wolff-Parkinson-White Syndrome.- Conclusions.- Phase Resetting: An Achilles Heel.- 4 The Measurement of Cardiac Output in Sinus Rhythm and Atrial Fibrillation.- Assessment of Cardiac Function.- The Assessment of Cardiovascular Function.- Measuring Volumetric Cardiac Output by the Fick Method..- The Indirect Fick Technique.- Thermodilution.- Reproducibility of Thermodilution.- Measurement of Cardiac Output by Echocardiography and Doppler Ultrasound.- Measurement of Aortic Cross-Sectional Area.- Measurement of Stroke Distance.- Linear Cardiac Output.- Relationship Between Body Surface Area and Aortic Cross-Sectional Area.- Effect of Age and Blood Pressure on Aortic Size and Stroke Distance.- Expectations of Linear Cardiac Output.- Comparison between Thermodilution and Doppler Ultrasound.- Relationship Between Linear and Volumetric Cardiac Output.- Application of Linear Cardiac Output Measurement to Atrial Fibrillation.- Average Stroke and Minute Distance in Atrial Fibrillation.- Beat-to-Beat Measurement of Stroke Output.- 5 The Haemodynamics of Atrial Fibrillation: The Development of a Model of Left Ventricular Function.- The Relationship Between Time and Volume of the Pulse.- Is Pulse Volume Irregularly Irregular?.- Derivation of a Mathematical Model of Left Ventricular Function.- The Physiological Basis for the Mathematical Model of Left Ventricular Function.- Effect of RR—1 on Stroke Distance: Preload.- Effect of RR—1 on Stroke Distance: Contractility.- The Effect of RR-1 on Stroke Distance: Afterload.- Effect of RR-2 on Stroke Distance.- Balance of Effects of RR-1 and RR-2.- Pulsus Alternans.- Application of the Mathematical Model of Left Ventricular Function.- Graphical Presentation of Multiple Regression Equation.- Haemodynamic Consequences of Atrial Fibrillation.- Venous Return.- Ventricular Filling.- Mitral Regurgitation.- Coronary Blood Flow.- Regional Blood Flow.- Systolic Time Intervals.- Endocrine Consequences of Atrial Fibrillation.- 6 The Haemodynamics of Atrial Fibrillation: The Effect of Ventricular Rate on Cardiac Output.- Further Information from Multiple Regression Analysis.- Three Haemodynamic Profiles.- Relationship between Stroke and Minute Output.- The Contribution of the Force-Frequency Effect to Maintenance of Cardiac Output at High Ventricular Rates.- The Predicted Effect of Heart Rate on Cardiac Output in Mitral Stenosis.- Effect of Irregularity Per Se on Cardiac Output.- The Ventricular Rate for Maximum Cardiac Output.- The Predicted Ventricular Rate for Maximal Cardiac Output 122 Relationship Between Slope of the Md/Mean VR Graph and Ventricular Rate.- Group Relationship Between Mean R-R Interval and Stroke Distance.- The Magnitude of the Effect of Ventricular Rate on Cardiac Output.- The Ventricular Rate for Maximum Cardiac Output: Sinus Rhythm.- Comparison of Atrial Fibrillation and Sinus Rhythm.- What is Meant by “Control” of Ventricular Rate?.- A New Concept of Control of the Ventricular Rate in Atrial Fibrillation.- 7 The Use of the Haemodynamic Model of Atrial Fibrillation for Evaluating Drug Action.- More Haemodynamic Profiles.- Additional Haemodynamic Data Derived from Stroke Distance.- A Pilot Study of the Effect of Enoximone in Atrial Fibrillation.- The Effect of Enoximone on the Haemodynamic Model.- Control of Ventricular Rate While on Enoximone.- A Placebo Controlled Trial of Enoximone and Digoxin in Atrial Fibrillation.- Conclusions.- 8 The Autonomic Control of Ventricular Rate in Atrial Fibrillation.- Respiratory Sinus Arrhythmia.- Quantifying Respiratory Sinus Arrhythmia.- Cheyne-Stokes Respiration.- Respiratory Variation of P-R Intervals.- Modelling the Effect of the Vagus on the Atrioventricular Node.- Respiratory Variation of Ventricular Rate in Atrial Fibrillation.- Modelling the Action of the Vagus on the Ventricular Response to Atrial Fibrillation.- Measurement of Baroreflex Function.- Ramp Method.- Neck-Suction Method.- Integration of Respiratory Sinus Arrhythmia and the Baroreflex.- The Frequency Response of the Heart Rate Control System.- A Systems Approach to Heart Rate Control.- The Effect of Ventricular Rate on Blood Pressure in Atrial Fibrillation.- The Effect of Ventricular Rate on Blood Pressure in Sinus Rhythm.- Regulation of Ventricular Rate in Atrial Fibrillation.- Conclusions.- 9 Clinical Aspects of Atrial Fibrillation.- Epidemiology.- Incidence.- Prevalence.- Prognosis.- Aetiology.- Coronary Artery Disease.- Myocardial Infarction.- Valvular Heart Disease.- Thyrotoxicosis.- Alcohol.- Metabolic Causes of Atrial Fibrillation.- The Role of the Autonomic Nervous System in Precipitating Atrial Fibrillation.- Physical Factors Precipitating Atrial Fibrillation.- Iatrogenic Atrial Fibrillation.- Self-Induced Atrial Fibrillation.- Congenital and Familial Causes of Atrial Fibrillation.- Infection and Infestation.- Malignancy.- Connective Tissue Disorders.- The Acute Abdomen.- Neurological Conditions.- Respiratory and Sundry Conditions.- Spontaneous Termination of Atrial Fibrillation.- Thromboembolism.- Prevalence of Thromboembolism in Atrial Fibrillation.- Prevalence of Atrial Fibrillation in Thromboembolism.- Prevalence of Stroke in Atrial Fibrillation.- The Prevalence of Atrial Fibrillation in Stroke.- Intracardiac Thrombi in Atrial Fibrillation.- 10 The Management of Atrial Fibrillation.- Presentation.- Symptoms.- Signs.- Investigations.- General Management.- Control of Ventricular Rate.- Digitalis.- Beta-adrenergic Blockers.- Calcium Antagonists.- Cardioversion.- Selection of Patients for Cardioversion.- Complications of Cardioversion.- Physiological Consequences of Cardioversion.- Long-Term Results of Cardioversion.- Chemical Cardioversion and Prevention of Atrial Fibrillation.- Quinidine.- Calcium Antagonists.- Disopyramide.- Propafenone.- Digoxin.- Beta-adrenergic Blockers.- Amiodarone.- Flecainide and Other Class 1 Agents.- Anticoagulant Therapy.- Rheumatic Valve Disease.- Non-rheumatic Atrial Fibrillation.- Cardioversion.- The Wolff-Parkinson-White Syndrome.- New and Experimental Techniques in Atrial Fibrillation Pacing.- Internal Cardioversion.- His Bundle Ablation.- Surgical Treatment for Atrial Fibrillation.- Appendix. A Simple Computer Model of the Electrophysiological System of the Heart, Considering the Sinoatrial and Atrioventricular Nodes as Sine Wave Oscillators.