Cardiometabolic assessment of lamin A/C gene mutation carriers: a phenotype-genotype correlation.

AIMS: Mutations of the LMNA gene encoding lamin A/C induce heterogeneous phenotypes ranging from cardiopathies and myopathies to lipodystrophies. The aim of this study was to compare cardiometabolic complications in patients with heterozygous LMNA mutations at the 482nd codon, the 'hotspot' for partial lipodystrophy, with carriers of other, non-R482 LMNA mutations. METHODS AND RESULTS: This study included 29 patients with R482 LMNA mutations, 29 carriers of non-R482 LMNA mutation and 19 control subjects. Cardiac and metabolic phenotypes were compared between groups. A family history of either cardiac implantable electronic devices (CIEDs; P < 0.001) or sudden death (P < 0.01) was more frequent in non-R482 than R482 carriers. The non-R482 carriers also had more abnormalities on electrocardiography and received CIEDs more often than R482 carriers (P < 0.001). On cardiac ultrasound, non-R482 patients had greater frequencies of left atrial enlargement (P < 0.05) and lower left ventricular ejection fractions (P < 0.01) than R482 carriers. In contrast, R482 carriers had lower BMI (P < 0.05), leptin (P < 0.01) and fat mass (P < 0.001), but higher intra-/total abdominal fat-mass ratios (P < 0.001) and prevalences of diabetes (P < 0.01) and hypertriglyceridaemia (P < 0.05) than non-R482 carriers, with a trend towards more coronary artery disease. However, non-R482 carriers had higher intra-/total abdominal fat-mass ratios (P < 0.02) and prevalences of diabetes (P < 0.001) and hypertriglyceridaemia (P < 0.05) than the controls. CONCLUSION: Non-R482 carriers present more frequently with arrhythmias than R482 carriers, who twice as often have diabetes, suggesting that follow-up for laminopathies could be adjusted for genotype. Non-R482 mutations require ultra-specialized cardiac follow-up, and coronary artery disease should not be overlooked. Although overlapping phenotypes are found, LMNA mutations essentially lead to tissue-specific diseases, favouring genotype-specific pathophysiological mechanisms.

[Implantable cardioverter defibrillators in pediatric patients: results in a series of 33 cases]. / Le défibrillateur automatique implantable chez l'enfant et l'adolescent: indications, complications et résultats à propos d'une étude multicentrique française de 33 cas.

UNLABELLED: Implantable defibrillator is the recognized treatment of sudden cardiac death. Miniaturization of the devices allows implantation in children. METHODS: This multicentric retrospective study analyzed data of 33 children aged 18 years and less who were implanted from 1990 to 2005. RESULTS: Age of patients are 10 to 18 years, 20 patients were implanted after a resuscitation of sudden death, 10 after a syncope, 2 after a ventricular tachycardia and 1 in a prophylactic way. Tachycardias on primary electrical disease are most frequent (46%). Hypertrophic cardiomyopathy accounts for 22%, DAVD for 14%, congenital cardiopathies for 12%. Seventeen patients received appropriate shocks and 14 patients had inappropriate shocks. There were two unexplained deaths. Five leads fractures and two device infections were noted. CONCLUSION: Implantable defibrillator is an effective treatment for children high-risk of sudden death. Occurrence of inappropriate shocks due to sinusal tachycardia, infections and leads fractures are frequent.

Extraction of endocardial implantable cardioverter-defibrillator leads.

Despite a growing number of implantable cardioverter-defibrillator (ICD) lead removal indications, there is no consensus about extraction techniques. We applied our experience of pacemaker lead removal to ICD leads using a superior approach with a standard extractor kit, and an inferior approach with a lasso, or a surgical extraction. Fifteen leads were removed in 11 patients during 12 procedures (1 patient was referred twice): 11 right ventricular defibrillation leads, 3 right atrial coils, and 1 atrial lead implanted with a DDD-ICD. The indication for lead extraction was insulation failure (n = 4), conductor fracture (n = 2), abdominal pocket infection (n = 4), lead endocarditis (n = 1), and replacement of an atrial coil by an atrial lead for DDD-R pacing (n = 1). One patient had surgical extraction of 2 leads because of an endocarditis with large vegetations on a DDD-ICD. In 11 other cases, 5 leads were removed using a superior approach with a standard extraction kit and 8 leads were removed by a femoral approach using a lasso alone or added to a pigtail catheter. There was no failure of explantation. One extraction attempt failed with the superior approach but was successful with a secondary inferior approach. The main difficulties encountered were due to tight adherence of the proximal coil to the venous wall and to dislodgment of passive fixation leads from their endocardial insertion. One patient had subclavian vein thrombosis after intervention; no major complication was noted. Ten patients immediately underwent reimplantation. Two patients (1 with an endocarditis and 1 free of ICD therapy for 5 years) did not have reimplantation. During a 4- to 44-month follow-up, no late complication appeared. Thus, ICD lead explantation can be performed with a good success rate, with extraction techniques similar to those used for pacemaker leads.

Ventricular tachycardia originating from the posteroseptal process of the left ventricle with inferior wall healed myocardial infarction.

Ventricular tachycardia (VT) substrates may form in preferential locations and similar electrocardiographic patterns may be observed when ventricular activation starts from a particular site. We examined the role of the posterior inferior process of the left ventricle in the mechanism of VT occurring after inferior wall myocardial infarction. We reviewed isochronal maps of 40 VTs obtained at surgery in 13 patients, with a 128-electrode system using epicardial sock and endocardial balloon electrode arrays. Based on the epicardial to left endocardial relation we observed 7 tachycardias in 7 patients with onset of activation over the crux of the heart. This activation mimicked excitation through a posteroseptal accessory pathway. Endocardial activation maps showed breakthroughs occurring 6 to 40 ms later and did not give evidence in favor of macroreentry. In all but 1 VT, left-axis deviation was present (-30 to -75 degrees) with a positive concordance from leads V2 to V6 (QRS wave patterns were variable in V1). These tachycardias, which were clinical in 3 of 7 cases, were interpreted as arising from the posterior inferior process of the left ventricle and successfully ablated by left septal and epicardial cryolesions. In another patient, this concept was further validated by percutaneous radiofrequency ablation of a tachycardia with the previously described morphology. In conclusion, VT may originate from the posteroseptal process of the left ventricle with inferior wall healed myocardial infarction. Because these tachycardias can be successfully eliminated, their characteristic morphologies may provide clinical markers for the identification of patient candidates to surgical or nonsurgical ablative therapy.

Single radiofrequency application to cure atrioventricular nodal reentry: arguments for the slow pathway origin of the high-low frequency slow potentials.

BACKGROUND: High-low frequency slow potentials are thought to be related to the slow AV pathway conduction. Their use was proposed to guide radiofrequency (RF) ablation of atrioventricular nodal reentrant tachycardia (AVNRT). The present study was designed to determine the prospective value of these high-low frequency slow potentials to guide AVNRT ablation using a single RF application. Single RF application could indeed reduce the size of the lesion created in the viciny of the specialized AV conduction system and shorten the radiation exposure and the overall duration of the procedure. RESULTS: Forty-one patients (14 men, 27 women, 45 +/- 16 years old) with AVNRT underwent slow pathway RF ablation guided by high-low frequency slow potentials. High-low frequency slow potentials were found in all patients along the tricuspid annulus and above the coronary sinus. Ablation was always performed in the posterior part of Koch's triangle. The mean A/V amplitude ratio of the successful site was 0.43 +/- 0.59. In 32 patients (78%) AVNRT was no longer inducible after a single RF application. Procedure and radiation times were 35 +/- 31 and 13 +/- 12 min respectively. Five patients required 2, 3 patients 3, and 1 patient 6 RF applications. The mean number of RF applications was 1.4 +/- 0.9 (median = 1). In the 32 patients who required only one RF application, 24 (75%) had an obvious dual AV nodal pathways with a jump before ablation, which completely disappeared in 18 of them (75%) after ablation. In the 6 remaining patients, who still had a jump after 1 RF application, there was no significant change in either conduction times or refractory periods concerning both the anterograde and retrograde AV conduction. No patient had PR interval purlongation. After a mean follow up of 11 +/- 5 months, recurrence was observed in a single patient who received 2 discontinued RF applications. CONCLUSION: Catheter-mediated ablation of AVNRT using high-low frequency slow potentials to localize the slow AV pathway is feasible and safe. Using this technique, a single RF application was successfull in 78% of patients, and slow pathway characteristics were completely eliminated in 75% of patients. The radiation time and the procedure duration were short. This suggest that, in patients with AVNRT, the choice of an appropriate RF target can reduce procedural duration.

[Epidemiology of paroxysmal auricular fibrillation]. / Epidémiologie de la fibrillation auriculaire paroxystique.

The epidemiology of paroxysmal atrial fibrillation (PAF) is poorly known because of the difficulties in setting up trials to study this condition. Its biannual incidence is about 2 per thousand. Its prevalence is 1 to 2% in a population of over 65 years of age. Paroxysmal atrial fibrillation is often asymptomatic. An initial episode of atrial fibrillation may remain a single event in a number of cases. Isolated paroxysmal atrial fibrillation progresses to permanent atrial fibrillation in about 20% of cases, usually if there is underlying cardiac disease. Rheumatic valve disease, cardiac failure, hypertension, previous myocardial infarction and cerebrovascular accidents are often associated with paroxysmal atrial fibrillation. Embolic complications are rare if paroxysmal atrial fibrillation is isolated.

[Use of semi-automatic defibrillators outside the hospital]. / Utilisation extrahospitalière du défibrillateur semi-automatique.

With an annual incidence of 1 to 2@1000 and a rate of survival without complication of 2%, sudden death outside hospital constitutes a serious public health problem in France. Ventricular fibrillation (VF) is responsible for more than three quarters of these deaths. The rate of survival is inversely proportional to the duration of VF making early defibrillation a strong link in the chain of survival. The chances of survival are much greater if the cardio-respiratory arrest occurs with a witness, basic first aid is started rapidly, diagnosis of VF is made quickly and the first shock is delivered as soon as possible. These last two criteria are being met more often since the advent of the semi-automatic defibrillator (SAD) and its availability to first line rescuers. The SAD is a light and compact defibrillator capable of automatic analysis of the electrocardiographic trace, charging if it detects ventricular tachycardia (VT) or VF. By analysing the QRS amplitude, its slope, its morphology, its spectral density and the duration of the isoelectric line, the SAD is capable of recognising VF with a sensibility of 98% and a specificity of 93%. The shock, however, is only delivered with a manoeuvre from the operator. The SAD memorizes both the rhythmic event treated and certain parameters relating to its use. During the last decade, the SAD has benefited from the technological evolutions of the implantable automatic defibrillator, with the introduction of a biphasic shock. The use of a biphasic shock allows reduction in the minimal defibrillation charge and thus lightens the apparatus and increases the number of shocks which the SAD can deliver on a charged battery. In authorizing paramedics by statute to use the SAD, it has been possible to reduce the interval from alert to first delivered shock to 8 minutes although it would be 10 minutes if the medical team was awaited, and to obtain a survival rate without complication of 6.3%. The progress achieved by the use of the SAD in the chain of survival cannot be denied. However, to surpass automatic defibrillation and widen the use of defibrillators to an informed and motivated public would certainly bring our results closer to those obtained in America where the survival rate reaches 30% in the best cases; subject to widespread first aid training for the population.

[Ventricular fibrillation after radiofrequency ablation of the atrioventricular node]. / Fibrillation ventriculaire dans les suites d'une ablation par radiofréquence du noeud auriculo-ventriculaire.

The authors report the case of a 77 year old patient who underwent radiofrequency ablation of the atrioventricular node for chronic. Invalidating atrial fibrillation, refractory to pharmacological therapy. A single chamber ventricular pacemaker was implanted one week before interruption of AV conduction. Eleven applications (7 on the right and 4 on the left side of the interventricular septum) were required for successful ablation. Four hours later, the patient developed episodes of non-sustained polymorphic ventricular tachycardia and torsades de pointe. These arrhythmias were initiated by long cycle-short cycle sequences and preceded by changes of ventricular repolarisation (prolongation of the spontaneous and paced QTc and JTc intervals). Eight days after ablation, the patient had an episode of ventricular fibrillation reduced by external DC shock. This arrhythmia was also preceded by changes in ventricular repolarisation. This case demonstrates the potential proarrhythmogenic effect of radiofrequency ablation of the AV node with changes in ventricular repolarisation which induces malignant ventricular arrhythmias. The authors suggest an appropriate preventive attitude. The progression in two distinct phases (immediate and late) imposes prolonged arrhythmia monitoring.

[Value of the tilt-table test in the management of unexplained syncope in children and adolescents]. / Intérêt du test d'inclinaison dans la prise en charge des syncopes inexpliquées de l'enfant et l'adolescent.

The value of the tilt test in assessing unexplained syncope in children and adolescents was investigated in 79 patients (41 girls and 38 boys, 12.3 +/- 2.9 years). The test was performed with a tilt of 60 degrees for 45 minutes. A pharmacological provocation with isoprenaline was carried out in negative passive test. The tilt test was considered to be positive in cases of symptomatic falls of the systolic blood pressure with or without bradycardia. Asystole was defined as a ventricular pause > or = 5 seconds. During the investigation, 52 patients (66%) reproduced symptoms related to vasovagal syncope in 45 patients (57%) or panic attack in 7 others (9%). Of the 45 presenting vasovagal syncope, 7 had a cardio-inhibitory reaction with asystole of 11.2 +/- 3.3 seconds. The other responses were vasodepressive in 17 patients and mixed in 21 patients. A comparative study did not reveal any significant difference between patients with a positive or negative test including those with panic attacks. Seventy-five patients were followed up for an average of 32 +/- 22.3 months. Preventive therapy was prescribed in 34 patients because of the frequency or severity of their symptoms. At the end, 10 patients (13%) had at least one recurrence of syncope, 3 in the group with panic attacks, 5 in non-treated patients (irrespective of the result of the tilt test) and only 1 in the group of 23 patients treated with beta-blockers. The authors conclude that with a diagnostic return of 66% in this series, the tilt test seems to be the non-invasive investigation of choice in unexplained syncope in children and adolescents. In addition, true vasovagal syncope can be differentiated from psychogenic.

[Complete atrioventricular block during temporal lobe epilepsy. Apropos of a case]. / Bloc auriculo-ventriculaire complet au cours d'une épilepsie temporale. A propos d'un cas.

The authors report the case of a 37 years old woman with no previous medical history, admitted to hospital for investigation of unexplained syncope, sometimes associated with generalised fits. After standard non-invasive cardiovascular investigations, no diagnosis could be made. The tilt test induced a minor syncopal episode without reproducing the clinical symptoms. In view of the discordance between the induced and spontaneous symptoms, a neurological opinion was requested. During the recording of an electroencephalogram, syncopal atrioventricular block was observed, preceded by auditory hallucinations, reproducing exactly the clinical symptoms. Analysis of the sequence of events showed the conduction defect to arise after the onset of the epileptic fit, indicating a diagnosis of syncopal complete atrioventricular block complicating cryptogenic temporal epilepsy, and requiring specific treatment. This case illustrates the importance of close collaboration between cardiologists and neurologists in the management of cases of unexplained syncope.

[Dual-chamber implantable automatic defibrillators. Experiences apropos of 16 cases]. / Le défibrillateur automatique implantable double chambre. Expérience à propos de 16 cas.

In view of the large number of inappropriate shocks observed in patients with implanted defibrillators, improved detection of ventricular arrhythmias has become a major objective. The addition of an atrial catheter has been proposed to improve discrimination between ventricular and non-ventricular arrhythmias. Besides this function, the additional catheter could be used for DDD pacing without risk of interaction between the pacemaker and defibrillator. The authors report their initial experience in 16 patients implanted with a DDD pacemaker. The indication was resuscitated sudden death (N = 5) or ventricular tachycardia (N = 11). The choice of a DDD defibrillator was justified by a bradycardia (N = 9), haemodynamic factors (N = 4) or supraventricular tachycardia (N = 3). The devices used were the Defender 9001 (ELA Medical SA, France, N = 3), the Ventak AV 1810 and the Ventak AV II DR 1821 (Guidant/CPI, Inc. USA, N = 11 and N = 2 respectively). There were three immediate complications. After 2 to 29 months' follow-up, 5 patients had received appropriate treatment by their devices. Five patients had inappropriate shocks : one patient received a shock triggered by electrical interference, two others had no active sensing algorithme when the shocks were delivered, and the other two had an activated algorithme with 1/1 conduction of a supraventricular arrhythmia. No recurrences were recorded after reprogramming the device. DDD or VDD pacing was permanent in 9 patients and intermittent in 3 others. Seven patients had dilated cardiomyopathy and severe cardiac failure and were clinically improved by dual chamber pacing. In many patients, candidates for a defibrillator, this new generation of devices has improved specificity of arrhythmia detection and cardiac pacing without risk of interaction. The authors propose a classification of the indications for a DDD defibrillator.

[Value of an implantable EKG monitor for the diagnosis of arrhythmic syncope in children]. / Intérêt d'un moniteur ECG implantable pour le diagnostic de syncopes rythmiques chez l'enfant.

The value of an implantable ECG monitor (Reveal TM Plus) is reported in a 12 year old child with unexplained syncopal episodes despite extensive investigations. Twenty-seven days after the implantation, ventricular tachycardia at 450/min was recorded at the first recurrence. This case shows that this type of monitoring can be particularly useful when an arrhythmia is thought to be the cause of syncope in a child and the initial investigation is negative.

[Contribution of the implantable ECG monitor in the etiologic diagnosis of syncope and unexplained recurrent syncopal attacks. Initial experience with 32 patients]. / Apport du moniteur ECG implantable pour le diagnostic étiologique des syncopes et lipothymies récidivantes inexpliquées. Expérience initiale à propos de 32 patients.

UNLABELLED: Following an exhaustive aetiological investigation, 10 to 26% of syncopal attacks remain unexplained. In these cases the correlation between symptoms and rhythm is a deciding step for the aetiological diagnosis. We report our initial experience using an implantable electrocardiographic monitor, a new diagnostic tool in patients suffering from syncope and recurrent unexplained syncopal attacks. RESULTS: The study included 32 patients (average age 55 +/- 22 years; 23 males) suffering from syncope and/or recurrent syncopal attacks remaining unexplained following an exhaustive aetiological investigation. The average follow up was 10.2 +/- 2.5 months. No case of sudden death was registered, and the device was removed in only one patient due to poor tolerance. During follow up, 21 recordings were memorized and analysed in 15 patients (45%), giving an average of 1.4 recordings per patient. The average interval for recurrence of symptoms after implantation was from 84 +/- 104 days, 75% of the episodes coming in the first 2 months following implantation. An arrhythmia was detected on 10 occasions: a malignant ventricular arrhythmia in 2 patients, a non-sustained ventricular tachycardia in 1 patient, a junctional tachycardia in 1 patient, entry into paroxysmal atrial fibrillation in 4 patients, a sinus bradycardia in 1 patient, and a sinus pause for 19 seconds in 1 patient. In one patient ST segment depression was documented following anterior chest pain. The tracing was normal with sinus rhythm recorded on 10 occasions, representing the only documented information in 4 patients. In total, an aetiology was found in 11 of the 32 patients evaluated (34%). Once the aetiological diagnosis was established and a specific treatment initiated, all the patients became asymptomatic. CONCLUSIONS: Our preliminary results underline the significance of the implantable ECG monitor in the diagnostic approach to recurrent unexplained syncopal attacks. The exact place of this tool in the decisional algorithm for syncope remains to be defined with further studies.

[Determinants of survival after implantation of an automatic defibrillator. Report of 127 patients]. / Déterminants de la survie après implantation d'un défibrillateur automatique implantable. A propos de 127 patients.

The authors present a retrospective and longitudinal study of the predictive factors of mortality in patients having an implanted automatic defibrillator. The population comprised 127 patients implanted between September 1988 and September 1997. There were 107 men with a mean age of 57.7 +/- 13 years. The left ventricular ejection fraction was 39.3%. The proportion of coronary patients was 68%; 20% of patients had atrial fibrillation and 5% were in Class III of the NYHA classification. The indications were: resuscitated cardiac arrest (N = 56) and poorly tolerated ventricular tachycardia (N = 71). The follow-up period was 30 +/- 25 months. There were 23 early and 10 late complications. Seventy-two patients had received an electric shock; 57 had an appropriate shock. There were 23 arrhythmic storms (ventricular arrhythmia requiring at least 2 shocks in less than 24 hours) in 17 patients. The operative mortality was 1.1%; at 1 year, the global survival was 93.9 +/- 2.2%; cardiac survival was 94.7 +/- 2.1%; survival without sudden death was 98.3 +/- 1.2%. Multivariate analysis isolated predictive factors for mortality; atrial fibrillation was predictive for global mortality; an ejection fraction < 30% and the fact of having received an appropriate shock were predictive of cardiac mortality; and an arrhythmic storm was predictive of sudden death.

[Anxiety disorders and unexplained syncopes of presumed vaso-vagal origin]. / Troubles anxieux et syncopes inexpliquées présumées d'origine vasovagale.

The impact of anxiety neurosis on the diagnosis and treatment of patients with unexplained syncope (S) was assessed in 178 patients (91 women and 87 men) with an average age of 36.5 +/- 20 years, presenting with 10.7 +/- 24 episodes of S). None had evidence of underlying cardiac disease apart from 7 patients with mild hypertension. All patients underwent a tilt test (TT) at 60 degrees for 45 minutes. A bolus of isoproterenol was injected intravenously in subjects with negative TT. After the test, the patients were classified according to the presence (n = 38) or absence (n = 140) of anxiety neurosis based on the DSM III-R diagnostic. The TT was positive in 76 patients, 9 of whom had a cardioinhibitory reaction with prolonged asystole. Patients with anxiety had more episodes of S (24 +/- 43 versus 7 +/- 13; p = 0.001), a shorter interval between S (11.5 +/- 23 months versus 12.5 +/- 20 months, p = 0.02) but more negative TT (27/38 versus 75/140; p = 0.05). One hundred and sixty-eight patients were followed up : 10 were lost to follow-up. Preventive treatment was undertaken in 59 patients who were representative of the whole group with respect to age (30 +/- 18 years 39 +/- 21 years : p = 0.004). After an average follow-up of 24.5 +/- 15 months, 26 patients (15%) experienced a recurrence of S. The recurrence rate was identical in patients with positive and negative TT and in treated and untreated cases. On the other hand, recurrence was higher in those with anxiety (12/25 versus 14/117; p = 0.001) who also had less improvement of symptoms (12/15 versus 74/120; p = 0.001). The "anxiety" variable was therefore identified as being the only predictive factor for recurrence of syncope. The authors conclude that in patients referred for investigation of unexplained syncope, some suffer from anxiety neurosis, in whom the TT is usually negative, and have a higher risk of recurrence. They justify a specific therapeutic management.

[Mapping and radiofrequency ablation in different forms of right peri-atriotomy flutter]. / Cartographie et ablation par radiofréquence des différentes formes du flutter péri-atriotomie droite.

Peri-atriotomy flutter is a possible complication of surgical atriotomy. This tachycardia in an indication for radiofrequency ablation. The aim of this study was to determine the mechanism of the flutter, evaluate the possibility of mapping and the role of radiofrequency ablation in its treatment. Eleven patients with a mean age of 45 years (26-70) were referred for ablation of atrial flutter observed on average 15 years after surgical atriotomy. In 7 patients (Group I), the ECG appearances before the procedure were that of a rare flutter. Endocavitary mapping showed a circuit limited to the free wall of the right atrium with a posterior caudo-cranial and an anterior cranio-caudal front. A series of radiofrequency applications joining the atriotomy scar to the inferior vena cava interrupted the flutter in all patients and created a bidirectional block around the atriotomy. In 4 patient (Group II), the ECG appearances were that of a common flutter. A series of radiofrequency ablations in the cavo-tricuspid isthmus led to sudden change in polarity of the F wave in all patients. Repeat mapping then showed a peri-atriotomy circuit identical to that described in Group I. The whole was interpreted as a figure-of-eight circuit. The primary success rate was 100%. There were no complications but the early recurrence rate remained high. This preliminary experience confirms the value of radiofrequency ablation in the treatment of peri-atriotomy flutter and shows ECG polymorphism related to a figure-of-eight reentry circuit.

[Is programmed ventricular stimulation still up to date in the medicinal evaluation of ventricular tachycardia?]. / La stimulation ventriculaire programmée est-elle toujours d'actualité dans l'évaluation médicamenteuse des tachycardies ventriculaires?

Despite considerable advances in the understanding of cardiac arrhythmia mechanisms, death in relation to ventricular tachyarrhythmias remains an important public health problem, and management of ventricular arrhythmias remains a perpetual challenge in clinical cardiology. In the last decade, the development and refinement of implantable cardioverter defibrillators and the progress in techniques of radiofrequency electrode catheter ablation and antiarrhythmic surgery have been revolutionary in the management of ventricular tachycardia. On the other hand, there have been major changes in the use of drug therapy since the publication of the results of the CAST study. Inclusion of mortality as an endpoint in clinical trials highlights the fact that some antiarrhythmic drugs may have the proclivity to exert fatal proarrhythmic reactions while also having the potential to control recurrences of ventricular tachycardia. All these changes that now need to be integrated into global approaches for ventricular arrhythmia control led us to wonder whether serial testing is still up to date in the management of ventricular tachycardia. After more than 20 years of clinical use, there is much concern about the use of serial drug testing to guide antiarrhythmic drug therapy for the management of life-threatening sustained ventricular tachyarrhythmias in light of recent advances in the management of cardiac arrhythmias. The purpose of this article is to discuss, within a relatively brief compass, the cumulative data from different lines of investigations, results of randomized clinical trials, recently acquired beliefs and meta-analytic findings concerning the present place of serial electrophysiologic drug testing in the management of ventricular tachycardia.

[Infections secondary to the implantation of a pacemaker: update]. / Infections secondaires à l'implantation d'un stimulateur cardiaque: mise au point.

Pacemaker lead infection is a major complication of endovascular permanent pacing. The incidence is less than 1% but it is a frequent disease due to the high number of pacemaker implanted. The diagnosis is difficult due to the insidious symptoms. Pacemaker infection must be systematically considered in patients with a pacemaker and symptoms of infection. Several investigations are useful for the diagnosis particularly the transesophageal echocardiography, but all investigations have a low negative predictive value. All of the implanted material must be completely removed.

[Determinants of malignant vasovagal syncopes with asystole disclosed by the tilting test and therapeutic implications]. / Déterminants de syncopes vasovagales malignes avec asystoles révélées par le test d'inclinaison et incidences thérapeutiques.

UNLABELLED: In order to evaluate the determinants of malignant vasovagal syncope with asystole revealed by the tilting test and to determine the possible therapeutic implications, 179 patients (91 women and 88 men, mean age 36.6 +/- 20.1 years) referred for the assessment of unexplained a were studied. The test was performed with a tilt of 60 degrees for 45 minutes. A bolus of isoprenaline (0.02 to 0.08 microgram/kg.min) was injected in the case of a negative passive test. Asystole was defined as a ventricular pause lasting > or = 5 seconds. RESULTS: Ten (13%) of the 77 patients with a positive tilting test experienced a cardio-inhibitory reaction with prolonged asystole lasting an average of 11.9 +/- 4.9 seconds. Compared to the other 67 patients with a positive test, those with asystole were younger (23/9 +/- 14.8 years vs 32.9 +/- 18.5 years, NS) and had a more frequent history of convulsions (6/10 vs 9/67, p = 0.05) during spontaneous episodes and trauma (9/10 vs 27/67, p = 0.005). Implantation of a pacemaker was chosen first-line treatment for the first 6 patients. Their follow-up tilting tests remained positive (pre S = 4, S = 1) despite DDD stimulation of 45 bpm. Five of these patients and the following 4 patients were retested under beta-blockers. In six patients treated with beta-blockers, the clinical symptoms resolved completely (n = 3) or improved (n = 3), in contrast with 3 other patients in whom the tilting test remained positive with recurrence of asystole. The mean follow-up for the 169 patients is 22.7 +/- 11 months and the ten patients with asystole remained totally asymptomatic. CONCLUSION: An asystolic response during the tilting test is characteristic of vasovagal syncope described as malignant. The syndrome essentially affects young patients, with a more frequent history of trauma and convulsions. Beta-blockers appear to be at least as effective as permanent pacemaker to prevent symptoms in this specific subgroup.

[VDD mode single electrode cardiac stimulation: indications, results and limitations of the method]. / La stimulation cardiaque en mode VDD à sonde unique: indications, résultats et limites de la méthode.

UNLABELLED: Several authors have reported the single atrioventricular (AV) electrode, comprising an atrial dipole floating in the right atrium, to be a system capable of providing results which are just as satisfactory as those of conventional systems (DDD). Between August 1992 and March 1995, a VDD single electrode pacemaker was implanted in 65 patients (mean age: 73 years +/- 17.2). The indication for implantation was isolated high degree AVB with no apparent sinus dysfunction. Four pacemakers were used: Vitatron (n = 24), Intermedics (n = 23), Medico (n = 13), Biotronik (n = 5). Intraoperative atrial endocavitary recording was 1.8 mV +/- 0.74. 17 patients died from a cause unrelated to pacemaker dysfunction. 4 patients were lost to follow-up. The remaining 44 patients were reviewed in our centre with a mean follow-up of 14.5 months +/- 7 months. Seven pacemakers (16%) were reprogrammed in VVI or VVI (R) mode, because of permanent atrial fibrillation in 3 cases, complete loss of atrial reception in 2 cases and late onset sinus dysfunction in 1 case. In the 41 patients in sinus atrial rhythm, the atrioventricular synchronization rate was greater than 90% in 88% of patients, equal to 76.3% in 2.4% of patients and atrioventricular synchronization was impossible in 9.6% of cases. CONCLUSION: The overall results of our preliminary experience of VDD mode single electrode pacemaker are moderate. The poor results essentially concerned patients with paroxysmal atrial arrhythmias prior to pacing.