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P Le Metayer

Publications and source records attributed to P Le Metayer.

At least 19 recordsLinked to original sources
PubMed2000

Prospective randomized comparison of irrigated-tip versus conventional-tip catheters for ablation of common flutter.

BACKGROUND: Radiofrequency (RF) ablation of common flutter requires the creation of a complete ablation line to produce bidirectional conduction block in the cavotricuspid isthmus. An irrigated-tip ablation catheter has been shown to be effective in patients in whom conventional ablation has failed. This randomized study compares the efficacy and safety of this catheter with those of a conventional catheter for de novo flutter ablation. METHODS AND RESULTS: Cavotricuspid ablation was performed with a conventional (n=26) or an irrigated-tip catheter (n=24). RF was applied for 60 minutes with a temperature-controlled mode: 65 degrees C to 70 degrees C up to 70 W with a conventional catheter or 50 degrees C up to 50 W (with a 17-mL/min saline flow rate) with the irrigated-tip catheter. The end point was the achievement of bidirectional isthmus block, and a crossover was performed after 21 unsuccessful applications. Procedural ablation parameters as well as number of applications, x-ray exposure, procedure duration, impedance rise, and clot formation were compared for each group. A coronary angiogram was performed before and after each ablation for the first 30 patients. Complete bidirectional isthmus block was achieved for all patients. Four patients crossed over from conventional to irrigated-tip catheters. The number of applications, procedure duration, and x-ray exposure were significantly higher with the conventional than with the irrigated-tip catheter: 13+/-10 versus 5+/-3 pulses, 53+/-41 versus 27+/-16 minutes, and 18+/-14 versus 9+/-6 minutes, respectively. No significant side effects occurred, and the coronary angiograms of the first 30 patients after ablation were unchanged. CONCLUSIONS: Irrigated-tip catheters were found to be more effective than and as safe as conventional catheters for flutter ablation, facilitating the rapid achievement of bidirectional isthmus block.

Aged↗
PubMed1999

[Inflammatory arteriopathy of the arms in the course of Horton disease. Report of six cases].

We report 6 cases of upper limb involvement in giant cell arteritis; upper limb involvement revealed the disease in 4 cases and clinical symptoms were present in 5 (upper limb pain, Raynaud's phenomenon). Upper limb pulses were not palpable and blood pressure unmeasurable in all. Duplex ultrasonography found signs of inflammatory arteriopathy in 4 cases (hypoechogenous halo of the arterial wall and acceleration of flow velocity). Arteriography was performed in 5 cases and showed long and regular stenoses. In the last case, arteriography was not done because the duplex exploration gave an easier diagnosis. With this technique, the diagnosis of upper limb involvement, frequent in autopsy series of giant cell arteritis, might be made more often. Corticosteroid therapy is indicated and surgery should be discussed only in emergency situations.

Aged↗
PubMed1995

[Management of nodal reentrant tachycardia with radiofrequency: predictive criteria of success].

Endocavitary catheter ablation by radiofrequency energy applied on the slow pathway is an effective method of treatment of nodal reentrant tachycardias. The aim of this report was to determine the criteria predictive of success during radiofrequency ablation of the slow pathway guided by the presence of slow potentials. Thirty-five patients (21 women, 14 men, mean age 44 +/- 14 years) with frequent attacks of junctional tachycardia were studied. After confirmation of the diagnosis by electrophysiological investigation, radiofrequency energy was delivered at a site characterised by the presence of slow potentials between the atrial (A) and ventricular (V) potentials. The criteria investigated at each site were: before application: A/V ratio; amplitude of A and V: maximum A/minimum A ratio; amplitude and duration of the A potential; during ablation: radiological stability of the catheter position and occurrence of a junctional rhythm. All 35 patients had successful procedures with no inducible tachycardia at the end of the procedure. The slow pathway was destroyed in 20 cases (57%) with no complication of atrioventricular block. The duration of the A potential was longer in the successful cases (56 +/- 16 vs 48 +/- 14 ms; p = 0.04). The appearance of junctional rhythm and catheter stability during the procedure were predictive of success (79% vs 48%; p = 0.02; 74% vs 43%; p = 0.01). The authors concluded that an ablation site with a long duration A potential and a slow potential is a good target. In addition, ablation should be started when the catheter is radiologically stable and should not be interrupted in the absence of a junctional rhythm.

Adolescent↗
PubMed1994

Catheter ablation of accessory pathways in children.

The efficacy and safety of catheter ablation of accessory pathways (AP) was studied in 79 children (age, 4-16 years), using DC shocks (n = 25) or radiofrequency energy (n = 54). All patients had documented arrhythmias including ventricular fibrillation in four. Organic heart disease was present in four patients. AP locations were left lateral (n = 36), posteroseptal (n = 36), right lateral (n = 8), Mahaim fibres (n = 2) and right anteroseptal (n = 6). Seven patients had multiple AP. One patient had a preexcitation which appeared secondary to an atrio-infundibular connection (Fontan procedure). The ablation site of concealed or overt AP was identified by retrograde or anterograde conduction mapping, respectively. A mean of 2.6 +/- 1 cathodal shocks (80-160 J) was delivered to 25 patients over 29 sessions, resulting in initial AP ablation in all. Fulguration was uncomplicated in all except in one patient (4%) who developed a secondary complete AV block post-ablation. During a follow-up period of 30-69 months, intermittent preexcitation recurred in two asymptomatic patients, but no significant tachycardia was inducible at late electrophysiological study, including under isoproterenol infusion. Radiofrequency energy was applied to 54 patients during 62 sessions, using 20-40 watts for 30-60 s. AP ablation was initially achieved in all patients using a median of three impulses, without significant immediate side-effects. Two patients (4%) developed a short episode of blurred vision possibly due to a microembolism. After discharge, the follow-up period was 10 +/- 5 months (range 1 to 24). All patients but one (98%) were asymptomatic without any drug therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Life-threatening pulmonary embolism with right-sided heart thrombus. Rapid recovery with recombinant tissue plasminogen activator.

We report the case of a woman treated with urokinase for acute pulmonary embolism with a right-sided heart thrombus. She developed life-threatening acute cor pulmonale which dramatically improved within 4 h with recombinant tissue plasminogen activator (rtPA). We emphasize the clinical interest of rtPA for the treatment of life-threatening pulmonary embolism.

Acute Disease↗
PubMed1991

Catheter ablation of left posteroseptal accessory pathways and of long RP' tachycardias with a right endocardial approach.

Fifty-four patients with a posteroseptal accessory connection and symptomatic tachycardias underwent catheter ablation of the anomalous pathway. Eight had the permanent form of reciprocating tachycardias (long RP' tachycardia) and 46 had a left posteroseptal preexcitation marked by a prominent R wave in lead VI. In 14 of 19 patients, ventriculoatrial conduction time during tachycardia lengthened in conjunction with functional left bundle branch block; this behaviour was significantly different from a series of patients with right posteroseptal preexcitation in which functional left bundle branch block lengthened the ventriculoatrial time in only one of 12 patients. A quadripolar electrode catheter was left within the proximal coronary sinus in order to locate the earliest atrial or ventricular activation site. The appropriate bipole was used as the radiographic and electrophysiological reference of the insertion of the accessory pathway. A catheter was then positioned on the septal side of the right atrium, outside the coronary sinus, so that atrial activity during reciprocating tachycardia and ventricular activity during preexcitation were synchronous with or earlier than that recorded within the proximal coronary sinus. Accessory pathway potential was not recorded in any patient. Early ventricular potential occurring --1.5 +/- 8 ms relative to delta wave onset was present at that site. In 38 patients, including 5 with permanent junctional tachycardia, high current (14 mA) pacing yielded direct ventricular paced QRS complexes (no delay spike-QRS) with a morphology similar to left posteroseptal maximal preexcitation. Slight movements of catheter position yielded significantly different pace-maps. One to eight 160 J cathodal shocks (510 +/- 213 J cumulative per patient) were delivered at this site in 61 sessions. Following fulguration, tachycardia recurred without drugs in only one patient over a follow-up period of 20 +/- 13 months. Asymptomatic intermittent preexcitation recurred in two patients. In all patients with long RP' tachycardia, the ablation procedure was successful without the need for drugs or permanent cardiac pacing. A long-term follow-up electrophysiological study in 18 patients demonstrated that conduction through the anomalous pathway was absent in 16 and deeply altered in the two patients with intermittent preexcitation; no tachycardia was inducible in any patient. In conclusion, catheter ablation of left posteroseptal accessory pathways is a feasible procedure using a right atrial approach outside the coronary sinus. This technique is also effective for the treatment of the permanent form of reciprocating tachycardia.

Adolescent↗
PubMed1991

Electrogram patterns predictive of successful catheter ablation of accessory pathways. Value of unipolar recording mode.

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, including 21 right parietal or anteroseptal, 47 posteroseptal, and 74 left lateral pathways. We sought to identify the type and value of electrophysiological parameters associated with successful ablation outcome. For this purpose, the unipolar recording mode was used in addition to bipolar anterograde and retrograde parameters. With a mean follow-up of 16 +/- 6 (mean +/- SD) months, fulguration was successful in eliminating preexcitation in 129 patients (96%), including all seven with two distinct accessory pathways. The first ablation attempt was successful in 110 patients, and two or more attempts were performed in 25 patients. Bipolar electrograms associated with success of fulguration showed a shorter atrioventricular conduction time (40 +/- 13 versus 53 +/- 17 msec, p less than 0.0001) and an earlier main ventricular deflection relative to delta wave onset (-1.7 +/- 10 versus 5 +/- 7 msec, p less than 0.001) than electrograms associated with unsuccessful outcome. The only parameter dealing with retrograde conduction (i.e., ventriculoatrial conduction time during reciprocating tachycardia) was not predictive (86 +/- 17 versus 93 +/- 17 msec). Neither was the atrial to ventricular electrogram amplitude ratio. Two unipolar parameters were found to be predictive of successful outcome: 1) The three different patterns PQS, P-QS, P-rS of unipolar waves recorded at the annulus were associated with respective success rates of 97%, 78%, and 55% (p less than 0.001). 2) Intrinsic deflection timing occurred -4 +/- 8 and 6 +/- 7 msec relative to delta wave onset in successful attempts and in failures, respectively (p less than 0.001). Logistic regression analysis revealed a single independent factor predictive of success, the unipolar pattern (p = 0.03), with an odds ratio of 7:1 (PQS pattern versus P-rS pattern). In the group of 18 patients who underwent a first unsuccessful but second successful attempt, comparison of electrograms revealed no difference in the ventriculoatrial conduction time but a significant improvement in anterograde parameters and unipolar pattern distribution. CONCLUSIONS: Some distinctive electrogram patterns concerning anterograde conduction are associated with success of accessory pathway fulguration. The unfiltered unipolar recording mode (PQS pattern) contributes significantly to optimizing the accuracy of accessory pathway localization.

Adolescent↗
PubMed1990

Catheter ablation of Mahaim fibers with preservation of atrioventricular nodal conduction.

Three patients with refractory preexcited tachycardia implicating Mahaim fibers underwent attempted catheter ablation of the accessory pathway. In the absence of demonstrable retrograde conduction in Mahaim fibers, we located the accessory pathway ventricular insertion site using the criteria of concordance between paced and spontaneous QRS morphologies during pace-mapping and earliest onset of local electrogram relative to surface preexcited QRS. At this site, a QS-like pattern of unfiltered unipolar electrograms with steep downstroke was recorded. The optimal site appeared radiologically at the right ventricular anterior wall or the adjacent septum, 2-4 cm from the tricuspid anulus. Three to six 160-J shocks were delivered at this site using an anterior chest wall plate as anode. After fulguration, conduction through the Mahaim tract was absent. A right bundle branch block persisted in two patients. All patients remained free of preexcited tachycardia during 12-16 months of follow-up. Postablation electrophysiological assessment showed no preexcitation in any patient. No reciprocating tachycardia was inducible, even during isoproterenol infusion. Atrioventricular nodal conduction parameters were unchanged from baseline study. Catheter ablation of Mahaim fibers is an effective alternative method for the treatment of tachycardias that include the accessory pathway in the circuit.

Adult↗
PubMed1986

[Oral propafenone in refractory arrhythmia. Apropos of 68 patients].

68 patients with rhythmical disorders unresponsive to treatment with one or several antiarrhythmics (quinidine derivatives 52 patients, amiodarone 28 patients, beta-blockers 24 patients) were treated by mouth with propafenone, with a mean postponement of 5.6 +/- 8.5 months (1 day to 33 months). Auricular arrhythmia was observed in 41 patients with the following results: 16 successes among the 24 patients with paroxysmal fibrillation of flutter, 3 successes among the 8 patients with an arrhythmia reduced by cardioversion, and 3 successes among the 9 patients with auricular tachycardia, including 6 systolic tachycardias. Of 8 patients with an intranodal reciprocal rhythm, 7 were treated successfully with propafenone, which acts on the retrograde part of the cycle. Successes were also recorded in 2 out of 3 patients with Wolff-Parkinson-White syndrome. In 19 cases of ventricular tachycardia, propafenone proved to be efficacious in 3 out of 5 cases presenting rapid discharges and in 7 out of 14 patients with continuous arrhythmias, notably those with a catecholaminergic component. Side-effects were digestive (5 patients), cardiac decompensation (3 patients), asthenia and asthma (1 patient) and the transformation of a flutter from 2/1 to 1/1 (1 patient).

Administration, Oral↗
PubMed1984

[Arrhythmia in relation to acute alcoholic intoxication in the absence of obvious cardiopathy].

Following acute intoxication with alcohol, 8 patients developed 16 episodes of arrhythmia, including 15 supraventricular tachycardias and one torsade de pointe. Seven of the 8 patients were chronically abusing of alcoholic drinks. None of the patients had clinically obvious cardiac pathology nor echocardiographic evidence of myocardiopathy. In 7 of them, however, baseline electrocardiograms disclosed disorders of intra-atrial conduction. The role of the different factors which might determine the occurrence of arrhythmia (notably alcohol, the autonomic nervous system, associated metabolic abnormalities and absorption of medicines) is discussed.

Adult↗