Paroxysmal Ventricular Tachycardia with Second Degree V-A Block and Reciprocal Rhythm

Abstract

An instance of paroxysmal ventricular tachycardia with retrograde conduction is presented. This occurred in a patient in the terminal stage of arteriosclerotic heart disease. The electrocardiograms obtained during this period, representative portions of which are illustrated, were unique in that reciprocal beats and fusion beats were noted; the latter being unusual because of the origin and site of fusion of the impulses. A hitherto unreported abnormality of the retrograde P wave is also described and illustrated.T HE OCCURRENCE of paroxysmal ventricular tachycardia exhibiting second degree V-A block with the Wenckebach phenomenon is a rarity in clinical electrocardiography.1-5 It is the purpose of the present report to add another case in which this arrhythmia was associated with reciprocal rhythm and to cite an abnormality of the retrograde P wave that has been hitherto undescribed. MATERIALThe following representative electrocardiograms were taken during the last three days before death in the case of a 76 year old physician who was admitted to the hospital because of severe congestive failure secondary to arteriosclerotic heart disease. Until the last twenty-four hours before death, the patient remained conscious and alert. His course in the hospital was complicated by frequent episodes of paroxysmal ventricular tachycardia. Treatment with digitalis was instituted with extreme caution in order to avoid conversion of the arrhythmia to ventricular fibrillation. All attempts to control the arrhythmia with quinidine, both orally and intravenously, were futile.From the Department of Medicine, Veterans' Administration Hospital, Bay Pines, Florida.Reviewed in the Veterans Administration and published with the approval of the Chief Medical Director. The statements and conclusions published by the authors are a result of their own study and do not necessarily reflect the opinion or policy of the Veterans Administration. 422He was questioned during the paroxysms of ventricular tachycardia, but no symptoms that might have been attributed to the change in cardiac rhythm were noted by him.Several long strips both of the sinus rhythm and the ventricular tachycardia were taken. The interpretation arrived at and illustrated by the portions of the electrocardiograms shown are based on careful analysis of these longer strips. The paroxysms were, in general, characterized by the following features:1. Abrupt Change in the Electrical Axis of QRS. It is well known that the shift of the electrical axis as illustrated in figure 1 may be altered, among other things, by aberrant ventricular conduction initiated either by supraventricular conduction defect, intraventricular block or by an idioventricular pacemaker. In figure 1 the electrical axis of QRS during the sinus rhythm is -65 degrees, while during the paroxysms it is + 115 degrees.2. V-A Block. As the paroxysms of tachycardia were being recorded instances were noted in which 1: 1 retrograde conduction occasionally occurred ( fig. 2). This was the exception rather than the rule...