Welcome to the second edition of Arrhythmia Grand Rounds. This edition sees the implementation of a number of new sections.
In keeping with the title of this journal, the first case is a power point presentation by Lokhandwala and Smeets (page 52) straight out of the EP lab with all the recordings shown in detail. This will be a challenge for the EP fellow and demonstrates the elegance of the electrophysiology lab in delineating the complexity of an otherwise superficially “simple” supraventricular tachycardia.
There are two case studies involving various aspects of fusion. One by Hodkinson and associates (page 53) shows intermittent fusion in the setting of a broad complex tachycardia and the second by Levine (page 72) shows progressive conduction abnormalities. Neither is associated with the “usual” interpretation of fusion and as such, become very instructive.
Agarwal and colleagues (page 56) present an unusual case of interference between two implantable devices placed in close proximity to one another. Once explained, it is fully understandable but was clearly not appreciated by the physicians implanting a breast tissue expander in a patient who already had an ICD. Similar conditions may arise in patients who have permanent breast implants.
There is a unique case demonstrating double activation of the coronary sinus by Shah and associates (page 58) that was only visible via the intracardiac recordings associated with a formal electrophysiologic study because the complexes would be too small to be seen on a surface ECG and/or hidden by the larger QRS complex.
Arrhythmia Grand Rounds is intended for individuals at all levels of training from the student, the allied professional, the cardiology fellow to the practicing cardiologist and super-subspecialist whose entire practice focuses on electrophysiology. As such, there will be materials appropriate for individuals at all levels of experience. There is a progressive tachycardia from a critically ill patient in an ICU (page 72) where the entire evaluation and discussion is based on the surface ECG. There is a unique example of using a standard dual chamber pacemaker with only a single lead in the right ventricle to achieve a functional form of cardiac resynchronization therapy by Finegan and associates (page 63) and an uncommon case of far field P oversensing in an ICD patient by Levine and colleagues (page 63). There is also a case study involving an adverse hemodynamic effect of flecainide by Ellis and associates (page 76).
In the section from the Basic Science Lab to the Bedside (page 79), Dr. Andrew Wit discusses the basic mechanism of Phases 3 and 4 (rate-dependent) AV block. This is not a common but never-the-less a very real entity and one that every physician should be familiar with. The paucity of the data may in part be due to the paroxysmal nature of this arrhythmia; hence, it is underestimated.
Four of the cases published in this issue of Arrhythmia Grand Rounds is accompanied by power point presentations. These can be saved to the reader’s own computer and used for teaching purposes. In three of these cases, each accompanied by a detailed text, the text can be reprinted for distribution to facilitate the educational exercise.
Virtually everyone has had one or more cases that they found both challenging and educational. We encourage you to share these with your colleagues via submissions to Arrhythmia Grand Rounds so that everyone can learn. One of the exciting things about all aspects of medicine, as science advances – we see things that previously were not appreciated and we continue to learn. A key clue to new concepts and ideas is the isolated case study that doesn’t fit the mold of conventional wisdom causing us and others to look further and reexamine our prior understanding. As most cases are new, one should expect the unexpected. So please, share your experience by submitting cases to Arrhythmia Grand Rounds.
Paul A. Levine, MD