Electrocardiographic Characteristics of Ventricular Arrhythmia Originating from the Left Coronary Cusp

Aortic cusps originating arrhythmias are rare; they have special electrocardiogram features that help to locate the site of origin. We report on a 20-year-old male patient without structural heart disease presenting with accelerated idioventricular rhythm; electrocardiogram analysis was typical of left coronary cusp origin

0166: New measurement of A/V ratio on the mitral annulus: interest in ablation

IntroductionMany ablations require radiofrequency delivery near to the mitral annulus (MA).No reliable data exists about the electrical criteria of mitral annulus localisation. The aim of this study was to measure the A/V ratio on the mitral annulus and compare it to the A/V ratio on its atrial and ventricular side with transesophageal echocardiographic guidance and catheter tissue contact monitoring.MethodsTen patients in sinus rhythm undergoing atrial fibrillation catheter ablation under general anesthesia using a contact-force sensing catheter were included. After double transseptal puncture, we recorded the atrial and ventricular potentials on the mitral annulus at four defined points (3,6,9 and 12 o’clock), with direct confirmation of the position of the catheter relative to the mitral annulus by transesophageal echocardio-graphy and contact assessment by the force sensor on the catheter tip. Then we performed the same procedure on the atrial and ventricular sides of the mitral annulus.ResultsThere is a homogeneous distribution of the amplitude of the atrial and ventricular electrograms on the mitral annulus with a good correlation (r=0,93; p < 0,0001). The mean A/V ratio was 0,57 (± 0,078, IC 95% 0,540,59) on the mitral annulus, 0,725 (± 0,09, IC 0,65-0,79) on the atrial side and 0,348 (± 0,09, IC 95% 0,18-0,41) on the ventricular side near to the mitral annulus. These results were significantly different (p< 0,0001). No correlation was found between this ratio and the size of the left atrium, left ventricular mass and the presence of hypertension.ConclusionsA/V ratio on the MA is 0.57. It is significantly different from the A/V ratio on the atrial and ventricular sides of the MA, and may be used as an electrical criterion for MA localisation during ablation proceduresAbstract 0166 – Figur

Technological advances in cardiac pacing and defibrillation

Since more than a half century, cardiac pacing and defibrillation represent a field in constant evolution, and they have shown some great technological advances from its conception to its methods of insertion. In this review, the recent developments about the accesses for pacemakers and ICD will be described: the axillary and the femoral vein. The His bundle pacing and the advantages of the entirely subcutaneous defibrillator will also be presented

Circadian variabilities of modulated ventricular parasystole

Acircadian rhythm of the discharge rate of continuous ventricular parasystole was recently described 1. This phenomenon, however, has not been previously reported in cases of modulated parasystole

Dynamics of, and alternating Wenckebach periods during, 4:1 and 6:1 atrioventricular block

In summary, the irregular dynamics of progression of 4:1 AV block in atrial flutter, presumably different from those observed in similar degrees of rate-dependent block, most likely reflected the complex electrophysiologic mechanisms operating during the highest degrees of AV nodal block. Occurrence of previously undescribed arrhythmias, namely Wenckebach periods during 4:1 and 6:1 block, tends to support the multilevel block hypothesis