Left Septal Fascicular Block: Characterization, Differential Diagnosis And Clinical Significance (hardcover)

This book provides clinical and electrovectorcardiographic evidence of the existence of left septal fascicular blocks and demonstrates the clinical importance of these blocks in the clinical scenario of acute coronary syndrome. There are currently no standard criteria for detecting conduction defects involving the third left fascicle, the septal or median fascicle, and the very existence of such defects is still a matter of controversy. This book provides acceptable and consistent terminology and definitions for the electrovectorcardiographic diagnosis of a left septal fascicular block. __Left Septal Fascicular Block: Characterization, Differential Diagnosis and Clinical Significance__ is an original and unique book that sheds light on an important topic of discussion in cardiac electrophysiology. Foreword 8 References 9 Authors 10 Contents 12 Chapter 1: The Trifascicular Nature of the Left Hisian System, Anatomical Variants and Coronary Irrigation 15 Introduction 15 The Sunao-Tawara Concept 16 Confirmation of the Trifascicular Concept of His Jr 17 The Quadrifascicular Concept or “Uhley’s Concept” 18 Anatomic Variations of Distribution and Blood Supply by Demoulin-Kullbertus 18 Distribution and Trajectory of the LSF 23 Blood Supply to the Cardiac Conduction System, Left Fascicles or Divisions – Modified from Frink and James (1973) 24 Notion of Coronary Circulation in the Heart and the Intraventricular Conduction System 24 Left Circumflex Artery 27 Right Coronary Artery 27 His Bundle and Bundle Branches 28 Bundle Branches 28 Left Fascicles Blood Supply 29 Other Arguments for the Trifascicular Nature of the Left Hisian System 30 References 33 Chapter 2: Ventricular Activation 36 The Durrer Concept 36 The Ventricular Activation Sequence 37 The First 1AM 10–20 ms Ventricular Activation Vector 39 Hypothetical Model of Ventricular Activation in Isolated LSFB 40 Initial Activation Vectors/Forces from 0 to 20 ms 40 Initial-Intermediate Vectors/Forces from 20 to 40 ms 41 Intermediate-Final Vectors/Forces from 40 to 60 ms 41 Basal Final Vectors/Forces from 60 to 100 ms or 110 ms 43 Electrophysiological Aspects of Conduction Velocity of Stimulus Inside the LSF 43 Characteristics of Purkinje Cells 44 Demonstration of LSFB by Electrical Endocardial Catheter Mapping 45 References 46 Chapter 3: Definition of Diagnosis 48 Numerous Nomenclatures Used for Left Septal Fascicular Block 48 Conclusion from the Semantic Discussion About Nomenclature 50 Possible Etiologies of LSFB 50 Electrocardiographic Criteria for LSFB (Pastore et al. 2009; MacAlpin 2002, 2003; Dabrowska et al. 1978; Abrahao et al. 1979; Sanches and Moffa 2001) 51 Vectorcardiographic Criteria for LSFB (All in the HP) (De Pádua et al. 1976; De Pádua 1977a, b; De Padua et al. 1978; Alboni et al. 1979; Inoue et al. 1983; Young et al. 1975; Nakaya et al. 1978; Sanches and Moffa 2001) 52 Model of the Sequence of Ventricular Activation in LSFB Associated to CRBBB 52 Electrovectorcardiographic Characterization of LSFB Associated with CRBBB 53 Differential Diagnosis with Other Causes of Prominent Anterior QRS Forces 54 Prominent Anterior QRS Forces Definition by Vectorcardiographic Parameters 56 Normal Characteristics of QRS and T Loops in the HP in Adults (Macfarlane and Lawrie 1989; Draper et al. 1964; Haywood and Selvester 1966; Benchimol and Desser 1975) (Fig. 3.5) 58 VCG Parameters Usefulness in Differential Diagnosis of Conditions Causing QRS Loop PAF in the HP 60 Possible Causes for PAF 63 Athlete’s Heart and “Athlete Heart Syndrome” with PAF 67 Misplaced Precordial Leads as Cause of PAF (Mattu et al. 2001; MacKenzie 2004; Pérez Riera et al. 2011) 69 Old Strictly Posterior, Dorsal, High Posterobasal MI (Actual Lateral MI) 69 Right Ventricular Hypertrophy (RVH): Vectorcardiographic Types A and B 73 Diastolic Left Ventricular Hypertrophy (LVH) or Eccentric Left Ventricular Hypertrophy, Secondary to Septal Hypertrophy (Increase of Vector 1AM and/or Heart CCW Rotation Around the Longitudinal Axis) (see Figs. 3.10 and 3.30) 75 Combined or Biventricular Loading or Biventricular Hypertrophy with PAF 79 Complete Right Bundle Branch Block (CRBBB) 81 Type A Pre-excitation Wolff-Parkinson-White (Bruyneel 1973) 84 Hypertrophic Cardiomyopathy (HCM): Non-obstructive (NO-HCM) and Obstructive (HOCM) 87 Duchenne’s Cardiomyopathy 93 Endomyocardial Fibrosis (EMF) 96 Dextroposition 98 References 102 Chapter 4: LSFB ECG/VCG Examples 109 References 152 Chapter 5: Final Conclusions 154 References 156 Index 157 "This book provides clinical and electrovectorcardiographic evidence of the existence of left septal fascicular blocks and demonstrates the clinical importance of these blocks in the clinical scenario of acute coronary syndrome. There are currently no standard criteria for detecting conduction defects involving the third left fascicle, the septal or median fascicle, and the very existence of such defects is still a matter of controversy. This book provides acceptable and consistent terminology and definitions for the electrovectorcardiographic diagnosis of a left septal fascicular block. Left Septal Fascicular Block: Characterization, Differential Diagnosis and Clinical Significance is an original and unique book that sheds light on an important topic of discussion in cardiac electrophysiology"- - Springer Front Matter....Pages i-xiii The Trifascicular Nature of the Left Hisian System, Anatomical Variants and Coronary Irrigation....Pages 1-21 Ventricular Activation....Pages 23-34 Definition of Diagnosis....Pages 35-95 LSFB ECG/VCG Examples....Pages 97-141 Final Conclusions....Pages 143-145 Back Matter....Pages 147-153