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P Jaïs

Publications and source records attributed to P Jaïs.

At least 55 records · Page 3Linked to original sources
PubMed2000

Multiple sources initiating atrial fibrillation from a single pulmonary vein identified by a circumferential catheter.

The pulmonary veins are the predominant source of ectopic activity initiating AF. The reproducibility of intrapulmonary vein activation during ectopic activity and/or initiation of multiple AF episodes was examined. Eighty-nine pulmonary veins (PVs) among 29 patients undergoing radiofrequency ablation of AF were studied with a 15- to 20-mm diameter, circumferential PV catheter equipped with ten electrodes and a deflectable shaft. Local electrograms were recorded simultaneously during sinus rhythm, ectopic activity, or AF onset, spontaneously or induced via the catheter left in a stable position. Fifty-four arrhythmogenic veins were identified, 39 showing isolated ectopy, and 8 displayed repetitive ectopy (in salvos). The earliest site of activation and the sequence of intra-PV activation during isolated ectopy was identical to that observed during consecutive ectopic complexes in 77% and variable in 23% during isolated ectopy. The earliest activity was sometimes limited to a single bipole. During repetitive ectopy and AF initiation, multiple sources and/or variable activation patterns were noted in 53% of instances, indicating the presence of multiple arrhythmogenic foci within the same PV. Simultaneous electrogram recordings with a circumferential PV catheter identified the presence of multiple arrhythmogenic foci within a single PV.

Atrial Fibrillation↗
PubMed2000

Concealed left pulmonary vein potentials unmasked by left atrial stimulation.

Pulmonary vein potentials (PVPs), though obvious during ectopic activity, are frequently invisible during sinus rhythm when they need to be distinguished from left atrial (LA) potentials to perform successful ablation procedures. Thirty-six patients with paroxysmal atrial fibrillation underwent circumferential PV mapping with a circular ten-electrode catheter during sinus rhythm, and during pacing from the right atrium, proximal and distal coronary sinus (CS), and LA. Ablation was performed at the ostium of the PV, the procedural endpoint consisting of electrical disconnection of the PV from the LA. A total of 93 PVs (excluding the right inferior PV) were mapped. During sinus rhythm, distinct right PVPs were present in all instances, while they were concealed within the electrograms recorded from the left inferior and superior PV in 23 (64%) patients. Distal CS or LA appendage pacing unmasked and separated left PV from LA potentials by a mean of 19 +/- 14 ms; the LA-to-left-PV potential interval measured 36 +/- 14 ms. The number of deflections also increased from 2.1 +/- 0.7 during sinus rhythm to 3 +/- 1.4 during LA stimulation. However, in the right superior PV, pacing caused overlapping of atrial potentials with right superior PVPs. RF ablation of the left PVPs was performed during distal or LA pacing in 23 patients, while in the right superior PV it was performed during sinus rhythm eliminating all, including unmasked, left PVPs, providing proof of their PV origin. Distal CS or LA pacing is required to recognize left PVPs in approximately 2/3 of patients and facilitates RF ablation.

Atrial Fibrillation↗
PubMed2000

Left ventricular diastolic dysfunction in patients with so-called lone atrial fibrillation.

Lone atrial fibrillation (AF) is defined by the absence of identifiable causes of AF, but its hemodynamics have not been investigated. Twenty-eight patients with lone AF were compared with 14 control patients referred for Wolff-Parkinson-White ablation. Transthoracic and transesophageal echocardiography were performed to rule out structural heart disease, followed by transseptally performed complete hemodynamic evaluation of the left heart systolic and diastolic function. There was no evidence of diastolic dysfunction according to echocardiographic criteria in AF and control patients. There was no difference in echocardiographic measurements, except for a significantly higher inferosuperior left atrial dimension seen in the four-chamber apical view in AF patients (51+/-10 vs 40+/-6 mm, P = 0.03). Hemodynamic evaluation showed that end-diastolic left ventricular pressure and the nadir of the left atrial Y descent were significantly higher in lone AF patients versus controls: 13+/-5 versus 8+/-3 mmHg (P = 0.001) and 6.7+/-3 versus 4.6+/-2.7 mmHg (P = 0.05). Our results demonstrated the presence of diastolic left heart dysfunction in patients with so-called lone AF.

Adult↗
PubMed2000

Catheter ablation of chronic atrial fibrillation targeting the reinitiating triggers.

INTRODUCTION: We assessed the mode of reinitiation of atrial fibrillation (AF) after cardioversion and the efficacy of ablating these foci of reinitiation in patients with chronic AF. METHODS AND RESULTS: Fifteen patients, 7 with structural heart disease, underwent mapping and catheter ablation of drug-resistant AF documented to be persistent for 5 +/- 4 months. In all patients, cardioversion was followed by documentation of P on T atrial ectopy and early recurrence, which allowed mapping of the reinitiating trigger or the source of ectopy. Radiofrequency (RF) ablation was performed at pulmonary vein (PV) ostia using a target temperature of 50 degrees C and a power limit of 30 to 40 W, with the endpoint being interruption of all local muscle conduction. A total of 32 arrhythmogenic PVs and 2 atrial foci (left septum and left appendage) were identified: 1, 2, and 3 or 4 PVs in 5, 3, and 6 patients. RF applications at the ostial perimeter resulted in progressively increasing delay, followed by abolition of PV potentials in 8, but potentials persisted in 6. A single ablation session was performed in 7 patients and 8 underwent two or three sessions because of recurrence of AF; ablation was directed at the same source due to recovery of local PV potential or at a different PV. No PV stenosis was noted either acutely or at repeated follow-up angiograms. Nine patients (60%) were in stable sinus rhythm without antiarrhythmic drugs at follow-up of 11 +/- 8 months. Anticoagulants were interrupted in 7 patients. CONCLUSION: PVs are the dominant triggers reinitiating chronic AF in this patient population. Elimination of PV potentials by ostial RF applications results in stable sinus rhythm in 60%. A larger group and longer follow-up are needed to investigate further the role of trigger ablation in curative therapy for chronic AF.

Adult↗
PubMed2000

Catheter ablation for atrial fibrillation.

Atrial fibrillation is frequently disabling and resistant to antiarrhythmic drugs. Curative treatment by catheter-based ablation has been shown to be feasible either by achieving long linear lesions, mainly in the left atrium, or by targeting the initiating focus, most frequently in the pulmonary veins. This paper reviews the different ablation approaches, their results, potential complications, and relative merits.

Atrial Fibrillation↗
PubMed2000

Electrophysiologically guided ablation of the pulmonary veins for the curative treatment of atrial fibrillation.

Catheter ablation of triggers that induce paroxysms of atrial fibrillation (AF) is an emerging curative therapy for this most common of supraventricular arrhythmias. In a series of 225 consecutive patients with multidrug resistant AF, 96% of triggering foci originated from one or several pulmonary veins (PV) independent of ambient ectopy or structural heart disease. This article describes an ablation procedure that is guided by activation mapping tailored to each individual PV, including criteria to define an arrhythmogenic PV, the use of provocative manoeuvres, the role of circumferential mapping catheters to provide information on the extent, distribution and activation of PV muscle as well as the monitoring of distal PV potentials (PVP) during ablation. Radiofrequency ablation to eliminate distal PVPs is performed by targeting the proximal PVP during sinus rhythm (right PV) or left atrial pacing (left PV). This end-point predicts a successful outcome more often than acute ectopy suppression. Complete elimination of AF is presently achieved in 70% of the patients, resulting in the elimination of antiarrhythmic treatment and suspension of anticoagulant treatment. It is anticipated that continued technological development will improve and facilitate this technique of curative treatment of AF.

Atrial Fibrillation↗
PubMed2000

[Definitions of second degree atrioventricular block. An exercise in logic in clinical electrocardiography].

Second degree atrioventricular block has received different definitions which make it difficult for physicians to interpret certain cases. This review of the literature provides an accurate definition of the criteria of Mobitz I and Mobitz II atrioventricular block, and proposes simple diagnostic methods based on conventional electrocardiography. The importance of the definitions is underlined and the consequences in terms of permanent cardiac pacing are emphasised.

Electrocardiography↗
PubMed1999

Efficacy and safety of septal and left-atrial linear ablation for atrial fibrillation.

Atrial fibrillation (AF), the most common of all sustained cardiac arrhythmias, is frequently resistant to antiarrhythmic drugs, and physicians have seen limited success with catheter ablation limited to the right atrium. As a result, the safety and efficacy of systematic biatrial linear ablation for drug resistant AF was investigated. Forty-four patients (54 +/- 7 years) underwent catheter ablation of daily drug-resistant AF. Two right-atrial lines (1 septal and 1 cavotricuspid) and 3-4 left-atrial lines were transseptally performed: 2 joining each superior pulmonary vein to the posterior mitral annulus and 1 interconnecting them. An additional left-atrial septal line from the right superior pulmonary vein (RSPV) to the foramen ovalis was performed in 23 patients. Radiofrequency was delivered with a conventional thermocouple-equipped ablation catheter or with an irrigated tip ablation catheter for resistant cases and for sparing the endocardium. Of the 44 patients, 25 (57%) were successfully treated without antiarrhythmic drugs. Twelve patients (27%) improved (<6 hours of AF per trimester under a previously ineffective drug) and 7 (16%) were considered treatment failures. Multiple sessions were required to ablate new left-atrial macro-reentry and initiating foci (2.7 +/- 1.3 procedures per patient). Five patients had a pericardial effusion and 1 each a pulmonary embolism, an inferior myocardial infarction, and a reversible cerebral ischemic event. One patient had thrombosis of the 2 left pulmonary veins. Despite a relatively high success rate, this procedure is too long, and the safely and efficacy need to be improved and applied to a broader range of patients.

Adult↗
PubMed1999

Clinical significance of multiple sensor options: rate response optimization, sensor blending, and trending.

The gold standard for rate modulation is the sinus node. To improve the rate modulation provided by artificial sensors, new sensors have to be developed or 2 different sensor systems can be combined within a single device. Association combination of a sensor with a rapid-response fast-rate increase sensor (activity) and a progressive, more specific sensor (QT ventilation) is generally used. Sensor combinations require adequate sensor blending for signal production and prioritization during rate modulation. However, in the new devices, some other aspects of rate modulation could be taken into consideration, particularly circadian rate variations to obtain lower rates at nighttime than during daytime, and automatic adaptation of the slope of rate increase during exercise, according to the patient's fitness, heart function, age, etc. Despite the need for automaticity, manual programming could continue to be useful to adapt rate modulation with data from sensor trending memories.

Circadian Rhythm↗
PubMed1999

High-density mapping of activation through an incomplete isthmus ablation line.

BACKGROUND: Activation mechanisms through gaps in ablation lines and resulting electrograms are poorly understood. METHODS AND RESULTS: Eight patients (all men; age, 59+/-9 years) were studied during a recurrence of typical atrial flutter (cycle length, 233+/-19 ms) after a previous catheter ablation in the cavotricuspid isthmus. High-density 3-dimensional mapping of the isthmus was performed with the Cordis-Biosense EP Navigation system, and local conduction velocity (CV) was estimated. Maps created with 96+/-19 points revealed 0.8+/-0.3-cm gaps of recovered conduction in the ablation line. A broad wave front entered the lateral isthmus with a CV of 1.8+/-0.7 m/s, halted on the lesion line, and penetrated slowly through the gap with a CV of 0.3+/-0.1 m/s. Activation then curved and returned antidromically to activate the downstream flank of the line with a CV of 1.1+/-0.7 m/s. This front fused downstream of the line with slow transverse activation (CV, 0.4+/-0.3 m/s) parallel to it. The ablation line was demarcated by an incomplete line of convergent double potentials with isoelectric intervals (from 123+/-34 to 62+/-16 ms); each potential corresponded to local activation upstream and downstream of the lesions, while the intervening delay was produced by slow conduction through the gap combined with the progressively longer curved pathway of downstream antidromic activation as a function of distance from the gap. CONCLUSIONS: High-density isthmus mapping during recurrent flutter indicates slow conduction through gaps of recovered conduction of varying dimensions in the ablation line followed by a curved front of activation antidromically activating its downstream flank, this detour producing wide double potentials on the line.

Atrial Flutter↗
PubMed1999

Partial cavotricuspid isthmus block before ablation in patients with typical atrial flutter.

OBJECTIVES: The purpose of this study was to prospectively evaluate preexisting partial isthmus block in the context of an electrophysiologically directed linear ablation strategy for typical atrial flutter (AF). BACKGROUND: Double potentials (DPs) separated by an isoelectric interval have been recognized as markers of local block. However, the presence and significance of DPs in the cavotricuspid isthmus during AF before ablation have not been evaluated. METHODS: Thirty consecutive patients with AF (counterclockwise: 24, clockwise: 6) were studied during AF. Sequential withdrawal mapping was performed in the cavotricuspid isthmus from the tricuspid valve (TV) to the inferior vena cava (IVC) edge with electrograms coinciding with the center of the surface electrocardiographic plateau during counterclockwise AF or with the initial downslope of the positive flutter wave during clockwise AF. Atrial electrograms along this line were categorized as double, single or fractionated potentials (SPs or FPs). After demarcation of the zone of contiguous DPs, radiofrequency (RF) catheter ablation was performed during AF only at sites with SPs or FPs (other than DPs) on the mapped line. If isthmus conduction still persisted after AF termination, additional RF applications were delivered using the same electrophysiologic strategy of avoiding DPs with an isoelectric interval during low lateral right atrial pacing for filling in the gap of residual conduction. RESULTS: Before ablation, no DPs were recorded in the isthmus in 19 patients (63%); DPs were recorded only at the IVC edge in five patients, and only at the TV edge in one patient. A contiguous line of DPs extending through more than half the isthmus to the IVC edge was documented in five patients (17%: group DP). In group DP, AF was terminated with 1.4+/-0.5 applications (vs. 5.8+/-3.5 in the remaining patients: p < 0.01). Complete isthmus block was achieved with a total of 3.4+/-0.5 applications (vs. 12+/-6 in the remaining patients: p < 0.01). CONCLUSIONS: Seventeen percent of patients undergoing ablation of AF have preexisting partial isthmus block indicated by a large contiguous zone of DPs separated by an isoelectric interval. Electrophysiologically directed linear ablation avoiding confluent DPs can prevent unnecessary applications for effective cure of AF.

Aged↗
PubMed1999

Catheter ablation of pulmonary vein foci for atrial fibrillation: PV foci ablation for atrial fibrillation.

While experimental and human mapping studies have documented multiple wavelet reentry as the electrophysiological mechanism maintaining atrial fibrillation, recent evidence shows that nearly all paroxysms of atrial fibrillation are initiated by trains of rapid discharges from the pulmonary veins. Radiofrequency catheter ablation targeting these initiating triggers has resulted in an overall 69% freedom from atrial fibrillation at a follow-up of 8 +/- 4 months in a population of 110 patients with paroxysmal atrial fibrillation. Six of the targeted pulmonary veins (4%) developed pulmonary vein stenosis; none requiring specific treatment. Catheter ablation of pulmonary vein foci initiating atrial fibrillation is therefore an effective curative modality for paroxysmal atrial fibrillation.

Atrial Fibrillation↗
PubMed1999

Successful radiofrequency ablation of a slow atrioventricular nodal pathway on the left posterior atrial septum.

RF catheter ablation is highly effective in eliminating atrioventricular nodal reentrant tachycardia by targeting the slow pathway in the posteroinferior part of Koch's triangle in the right atrium. We report here a patient in whom "slow-fast" atrioventricular nodal reentrant tachycardia was eliminated only by ablation of the slow pathway in the left atrial posteroseptal region at the level of the mitral annulus after unsuccessful attempts at the traditional site on the right side.

Adult↗