Evaluation of SA Nodal Abnormalities Anatomy of the SA Node The SA node can be thought of as a subendocardial, comma-shaped structure, approximately 3 mm in width and 10 mm…
The Technology of Transcatheter Ablation Successful transcatheter ablation requires three things. First, a thorough understanding of the arrhythmia being treated—specifically, a precise understanding of the location and physiology of the…
General Classification of Supraventricular Tachyarrhythmias As described in Chapter 2, most supraventricular tachyarrhythmias are caused by either abnormal automaticity or reentry. Automatic Supraventricular Tachyarrhythmias Automatic supraventricular tachyarrhythmias are relatively uncommon,…
Ventricular Tachyarrhythmias and Sudden Death Sudden death (death that is instantaneous and completely unexpected) may well be the major public health problem in the United States today. If this statement…
Recording and Pacing To discuss intracardiac recording and pacing, we need to introduce two terms that are used by electrophysiologists relating to time measurements. Time measurements are reported in milliseconds…
Bradyarrhythmias There are two broad categories of abnormally slow heart rhythms—the failure of pacemaker cells to generate appropriate electrical impulses (disorders of automaticity) and the failure to propagate electrical impulses…
The Anatomy of the Heart’s Electrical System The heart’s electrical impulse originates in the sinoatrial (SA) node, located high in the right atrium near the superior vena cava. The impulse…
Cardiac Resynchronization Therapy (CRT) How it Works Cardiac resynchronization therapy (CRT), also referred to as biventricular pacing, is aimed at improving the disordered patterns of ventricular contraction—referred to as ventricular…
Pharmacologic Therapy Antiarrhythmic drugs are not arrhythmia suppressants in the same way that menthol is a cough suppressant. They do not work by soothing irritable areas. In fact, most antiarrhythmic…
The Three Steps in Evaluating and Treating Cardiac Arrhythmias The appropriate management of cardiac arrhythmias involves following a predetermined plan of therapy aimed at achieving specific goals. Those goals, in…
