1/3. Wolff Parkinson White (WPW) syndrome: what the critical care nurse needs to consider when administering antiarrhythmics.This paper discusses the importance of critical care and emergency nurses having an understanding of why pre-existing cardiac disorders can influence antiarrhythmic treatment. The patient with a pre-excitation syndrome is usually managed in a coronary care unit. However, these patients may be admitted to an intensive care unit (ICU) with complications of Wolff Parkinson White (WPW) syndrome; for example post cardiopulmonary arrest or WPW as a co-morbidity. It is common practice in critical care areas for registered nurses to administer antiarrhythmics without a doctor's prescription in life-threatening situations. Therefore, the critical care nurse must have knowledge of the implications of administering standard antiarrhythmic agents if this patient reverts into a tachyarrhythmia. If antiarrhythmics are administered that are contraindicated in patients with WPW syndrome, then there is potential for deleterious effects. This case study highlights the different pharmacological agents for treating tachyarrhythmias in a patient with WPW syndrome. The paper outlines the correct treatment and discusses the deleterious effects of incorrect administration of drugs in WPW syndrome.- - - - - - - - - - ranking = 1keywords = pre-excitation (Clic here for more details about this article) |
2/3. "Nodoventricular" accessory pathway: evidence for a distinct accessory atrioventricular pathway with atrioventricular node-like properties.Two patients are described with recurrent pre-excited tachycardia and electrophysiologic characteristics typically ascribed to a nodoventricular accessory connection. The accessory pathway in each case demonstrated rate-dependent prolongation of conduction time and a low right ventricular insertion site; it was associated with a left bundle branch block configuration during pre-excitation. Intraoperatively, the pathway was demonstrated to originate at the anterior right atrioventricular (AV) anulus and not at the AV node. These data suggest that a "typical" nodoventricular pathway, by electrophysiologic criteria, may in fact be an AV pathway with AV node-like conduction properties and a distal right ventricular insertion site.- - - - - - - - - - ranking = 1keywords = pre-excitation (Clic here for more details about this article) |
3/3. Periodic occurrence of premature atrial beats inducing alternation during supraventricular tachycardia in a case of pre-excitation syndrome.During orthodromic atrioventricular reciprocating tachycardia (AVRT) in a patient with pre-excitation syndrome, 2:1 to 9:1 cycle length alternation was observed. The alternation was induced by the development of premature atrial beats (PABs) recurring in every three to ten AVRT beats. An electrophysiologic study revealed that: 1) PAB developed periodically during atrial/ventricular tachy-pacing (at a rate of 140-170 times/min), during atrial/ventricular extrastimulus study, and during electrically induced AVRT. 2) The PAB had a constant coupling interval to the preceding atrial complex, probably an atrial echo beat, and was associated with no His bundle or ventricular deflection. 3) An intensive search failed to reveal any third ventriculo-atrial conduction pathway. The PABs may have been induced by intra-atrial reentry or by triggered activity in the atrium.- - - - - - - - - - ranking = 5keywords = pre-excitation (Clic here for more details about this article) |