Reentry Tachycardia
3.11 Reentry Tachycardia AV Nodal Reentry Tachycardia (Slow–Fast Type) Termination mechanism: After establishing the reentry circuit, sudden blockade of retrograde conduction in the fast pathway, hence no excitation of the…
Right Bundle Branch Block
3.3 Right Bundle Branch Block Isolated Complete Right Bundle Branch Block Mechanism: Delayed conduction in the right bundle branch, secondary (delayed) excitation of the right ventricle via the left ventricular…
Left Bundle Branch Block
3.4 Left Bundle Branch Block Isolated Complete Left Bundle Branch Block Mechanism: Block in the left bundle branch resulting in secondary (delayed) excitation of the left ventricle via the right…
Medication-Related ECG Changes
5.11 Medication-Related ECG Changes Class IA Antiarrhythmics (E.g., Quinidine) ECG characteristics: Class IA: Quinidine, disopyramide, procainamide Mechanism of action: Blockade of the voltage-dependent sodium channels raising the threshold potential (phase…
Atrial Fibrillation
3.10 Atrial Fibrillation Comparison of Isthmus-Dependent “Typical” Atrial Flutter (Counter-Clockwise vs. Clockwise) Atrial Fibrillation—In General Mechanism: Mostly left atrial micro-reentry with changing circuits of excitation Left atrial dilatation has a…
Stress-Induced Ischemia in Coronary Heart Disease
4.2 Stress-Induced Ischemia in Coronary Heart Disease Stress-Induced Ischemia in Coronary Heart Disease Mechanism: In the affected area the inner myocardial layer (endocardium) is particularly susceptible to ischemia (so-called last…
Further Explanations
2.6 Further Explanations (I) Blockade of conduction arises between the sinus node and the atrium or in the region of the AV node (between the atrium and the ventricle). A…
“Typical” Atrial Flutter
3.9 “Typical” Atrial Flutter Nonisthmus-Dependent “Atypical” Atrial Flutter (Right Atrial With Atrial Septal Defect) Differential diagnosis: Typical atrial flutter Atrial ectopic tachycardia AV nodal reentry tachycardia Orthodromic WPW tachycardia Sinus…
Mixed Types of Block
3.5 Mixed Types of Block Left Posterior Hemiblock Differential diagnosis: Right bundle branch block Left bundle branch block Left anterior hemiblock Bifascicular block WPW syndrome Bifascicular Block—Complete Right Bundle Branch…
Ventricular Tachycardia
3.13 Ventricular Tachycardia Slow Monomorphic Ventricular Tachycardia Following Anterior Infarction, Spontaneous Termination Etiology: Coronary heart disease with status post infarct Mechanism: Area in the region of the infarction scar with…
