207 Incidence and clinical significance of the asssociation of paroxysmal supraventricular and ventricular tachycardia

Abstract

Fine-QRS complex tachycardia alternating with wide-QRS complex tachycardia can lead to an erroneous diagnosis of paroxysmal supraventricular tachycardia (SVT) with or without aberrancy. The purpose of the study was to evaluate the incidence and the significance of the association of SVT and ventricular tachycardia (VT) in the same patient. 898 patients aged from 11 to 88 years were consecutively admitted for a sustained VT; 818 patients had associated heart disease (history of myocardial infarction 374, idiopathic dilated cardiomyopathy 69, arrhythmogenic right ventricular dysplasia 86, miscellaneous 289) and 80 had no apparent heart disease. Electrophysiological study including programmed atrial and ventricular stimulation, 2D cardiac echocardiography, coronary angiography in patients older than 40 years, right ventricular angiography and cardiac RMI since 2002, were performed in these patients. Fifteen patients presented (2%) with either SVT or VT. All SVT's were related to an atrioventricular node reentrant tachycardia (AVNRT). The association of SVT and VT was significantly more frequent in patients without heart disease and with verapamil-sensitive VT (n=6/80, 7.5%)(<0.001), arrhythmogenic heart disease (n=4/86, 5%)(0.05) than in those with myocardial infarction (n=4/374, 0.1%) or dilated cardiomyopathy (n=0). Among 692 patients with AVNRT, 39 had associated heart disease and only 5 have both tachycardias. Radiofrequency ablation of AVNRT performed in all patients did not change the recurrence of VT which required ablation in 3 patients and the implantation of antitachycardia device with defibrillator in 2 patients. The association of SVT and VT is rare in patients with heart disease except in those with arrhythmogenic right ventricular dysplasia. The association is more frequent in patients without heart disease diagnosis and could be underestimated; fine QRS complex tachycardia alternating with wide QRS complex tachycardia leads generally to the erroneous diagnosis of SVT with or without aberrancy.