INTRODUCTION Recent studies have demonstrated that the most common site of accessory pathway conduction block following the introduction of a premature atrial stimulus during atrial pacing is between the accessory pathway potential and the ventricular electrogram, consistent with block at the ventricular insertion of the accessory pathway. However, no prior study has evaluated the site of condu...

AIMS The site of successful ablation of the slow atrioventricular (AV) nodal pathway may be located in the posteroseptal or midseptal area. We have previously shown that the site of successful radiofrequency (RF) ablation of the slow pathway, rather than residual slow pathway conduction correlates with AV nodal re-entrant tachycardia (AVNRT) recurrences, with more recurrences noted in inferopos...

It has been postulated that rotation of the left ventricular apex with respect to the base is a component of normal systolic function in humans, but it has been difficult to measure it noninvasively. Tagging is a new magnetic resonance imaging technique that labels specific areas of myocardium by selective radio-frequency excitation of narrow planes orthogonal to the imaging plane before acquir...

CLINICAL SUMMARY A 38-year-old man was referred to the University of Catania for severe mitral regurgitation caused by bacterial endocarditis in a myxomatous mitral valve, with prolapse and chordal rupture of the posterior leaflet. The patient was symptomatic for effort dyspnea. A preoperative echocardiogram showed a dilated left ventricle with 62% ejection fraction. Moderate to severe tricuspi...

BACKGROUND Transcatheter electrical ablation has been used in the treatment of arrhythmias, and most experience has been obtained by ablating the normal atrioventricular conduction system. Less information is available on ablation of atrioventricular accessory pathways. METHODS AND RESULTS Catheter ablation of overt accessory pathways was attempted in 135 patients with 142 distinct pathways, ...

BACKGROUND Recent studies of human type 1 atrial flutter demonstrated reentry in the right atrium and an area of slow conduction in the low posteroseptal right atrium. Direct-current catheter ablation of this area has been only moderately successful in preventing recurrence. Therefore, we performed endocardial activation mapping and entrainment pace mapping during atrial flutter to determine th...

The permanent or recurring form of junctional reciprocating tachycardia (PJRT) is an incessant tachycardia that has characteristically been refractory to medical therapy. Nine patients with PJRT refractory to medical therapy were referred for evaluation and electrophysiologic study. All nine patients had the characteristic clinical and electrophysiologic features of PJRT. Each patient demonstra...

I Wellens HJJ, Brugada P, Penn OC, Gorgels AP, Smeets J. Pre-excitation svndromes: clinical presentation, course and therapy. In: Zipes DP, Jalife J, eds. Cardiac electrophvsiology: from cell to bedside. Philadelphia: W B Saunders, 1990:691-702. 2 Klein GJ, Bashore TM, Sellers TD, Pritchett ELC, Smith WM, Gallagher JJ. Ventricular fibrillation in the Wolff-Parkinson-White syndrome. N Engl3' Med...

To determnine the effects of ventricular preexcitation via accessory atrioventricular connections (ACs) on the sequence of basal ventricular activation, electrophysiologic study records of 22 patients with AC were reviewed. In each, AC site was confirmed by mapping done at operation. Local ventricular preexcitation (VP), defined as earlier timing of a local ventricular electrogram relative to t...

Functional tricuspid regurgitation (FTR) is a neglected and underestimated pathology. It occurs mostly from annular dilatation and right ventricular enlargement, which is frequent secondary to left-sided heart failure from myocardial or valvular causes, right ventricular volume and pressure overload, and dilatation of the cardiac chambers. Moderate-to-severe FTR should be corrected to improve s...