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The mainstay of treatment for atrial fibrillation (AF) remains pharmacological, however, catheter ablation, since an early attempt in 1994 has undergone many evolutions up to the present day whereby it has taken an increasing place in the management of this arrhythmia. In paroxysmal AF, the most recent studies report a success rate of more than 80% at 1 year of follow-up after a single procedure (free of symptoms without antiarrhythmic drugs). In persistent AF the technique continues to evolve with a success rates between 70% and 95% even if several long and complex procedures are often needed, which are not without risk, to achieve these results. With constant improvement in this field catheter ablation has become a valuable tool in the management strategy of AF.

Objective: To determine clinical features, management and prognosis of cardiac conduction abnormalities (CCA) complicating abscessed endocarditis., Methods: We have analysed clinical, microbiologic and echocardiographic datas, therapies and outcome of cardiac abscesses complicated by CCA in patient hospitalized between 1995 and 2001 in our centre., Results: Above 35 cardiac abscesses, six men (mean age 62 years) had CCA complicating six aortic ring abscesses (4 on native valve and 2 on prosthetic valve) with four cases of interventricular septal involvement and fistulization. Severe heart failure is present four times, a septic cerebral embolization twice. Streptococcus and Staphylococcus prevail. Complete atrioventricular block (AVB) reveals endocarditis twice and complicates the evolution three times. Trifascicular block (first degree AVB, left anterior fascicular block and complete right bundle branch block) revealed recurrence of endocarditis. Two patients were treated medically: one died quickly (complete AVB pre-mortem), and the other one had favourable issue (paroxystic complete AVB). Four patients had surgery with temporary pacemaker in three cases (one died) then definitive pacemaker in two cases. At 26.5 month (7-50), the four survivors had no recurrence of endocarditis., Conclusion: Severe CCA are classical in aortic ring abscessed endocarditis and associated with increased mortality. Immediate transfert in a dentre with cardiac surgery is necessary. Definitive cardiac pacing can be performed early without leads infection.

The possibility of curing patients suffering from paroxysmal atrial fibrillation using a radiofrequency ablation treatment is a major change in the management of this arrhythmia. Pulmonary vein disconnection is efficient and safe after a learning curve of the operator. This pulmonary vein isolation is the first and mandatory step allowing disappearance of atrial fibrillation in 70% of the patients. Modification in fibrillatory substrate using linear lesions increases the rate success to 75% in chronic atrial fibrillation and to 82% in paroxysmal atrial fibrillation. The radiofrequency ablation of atrial fibrillation should be considered as a surgical treatment without an open heart, isolating structures and cutting tissues are technical improvements (new radiofrequency catheters) will probably facilitate in the future. Some comparative studies with medical treatment are currently evaluating their efficacy, safety and respective cost and they may lead to a considerable increase in the number of patients who could benefit from these curative treatments.

In an adult population, the prevalence of sleep apnea is 4% for men and 2% for women. Generally, nasal positive pressure ventilation is the best therapeutic option. To date, and in spite of the possible presence of marked brady-arrhythmias during sleep apnea, there is no recognised indication for Pacemaker implantation. However, recent data show the potential benefit of permanent cardiac stimulation in these patients. Increasing heart rate (using atrial pacing) improves cardiac output, and reduces pulmonary congestion and pulmonary vagal afferent nerves are no longer stimulated. The incidence of central sleep apnea is thereby reduced. Excessive nocturnal vagal tone increases snoring and sleep apnea, because of excessive relaxation of the oropharyngeal muscles. In patients with bradycardia, atrial stimulation may oppose increased vagal tone, by stimulating the sympathetic system or maintaining it at a minimal level. It is therefore possible that cardiac stimulation will become part of the treatment of sleep apnea in patients with documented bradycardia and/or heart failure.

In this study, 9 cases of tachycardia-induced cardiomyopathy have been reported, with a 7-year follow-up period. The patient population consisted of 5 males and 4 females with a mean age of 41 +/- 18 years (range: 10-70 years). It was difficult to determine the onset of the arrhythmia, due to its frequently asymptomatic course until such time as cardiac insufficiency became apparent (this was the case in 7 patients, while 2 subjects had palpitations). Four cases of AV intranodal reentry tachycardia (3 with an accessory pathway), 2 cases of atrial fibrillation, 1 case of auricular flutter, 1 case of atrial tachycardia and 1 case of ventricular tachycardia were observed. Disappearance of the symptomatology following restoration of sinus rhythm was accompanied by echocardiographically-determined normalization of systolic function on average 5 +/- 4 months post-arrhythmia (range: 1-12 months). Left-ventricular end-diastolic volumes decreased from 60 +/- 5 mm to 51 +/- 4 mm (P < 0.01), and end-systolic volumes from 50 +/- 7 mm to 35 +/- 4 mm (P < 0.001), while the left ventricular shortening fraction increased from 17 +/- 5% to 33 +/- 4% (P < 0.0001). In the differential diagnosis for primary dilated cardiomyopathy, tachycardia-induced cardiomyopathy appears very similar to the former, and only an adequate period of follow-up after the restoration of sinus rhythm can confirm the diagnosis.

Quality of life (QOL) measurements are one of the main determinants for indication and technologic choice in permanent cardiac pacing. QOL measurements are obtained using questionnaire application. Questionnaire for QOL has to be reliable, comprehensive, sensitive and specific. Pacing mode and pacemakers algorithms have been evaluated by QOL measurements: VVI vs DDD, DDD vs VVIR, AAI vs DDD, fall back, algorithm.... Survival data and costs are also relevant aspects of cardiac pacing evaluation.

Flecainide acetate is a powerful antiarrhythmic initially used to treat ventricular arrhythmias. Despite an excess mortality in this indication and in the presence of heart disease, flecainide remains a good antiarrhythmic for supraventricular tachycardias in a healthy heart.

Junctional tachycardias may be related to intranodal reentry or to the existence of an accessory pathway. All are suitable for radical treatment by radiofrequency current applied either in the perinodal region or at the tricuspid or mitral atrioventricular rings respectively. 176 patients with intranodal reentry were treated by preferential modification of the rapid (8) or slow (167) anterograde pathway of the reentry circuit, with a 99% success rate (1 failure) and without significant complications, in particular atrioventricular block in the case of ablation of the slow pathway. 362 patients with one or more accessory pathways, patent or latent, were treated using the same type of energy. The ablation site was determined on the basis of indirect criteria and/or recording of the specific activity of the accessory pathway. The success rate here was 98%, once again without significant complications with the exception of those inherent to catheterisation procedures. Treatment duration time was 41 +/- 38 min in the treatment of intranodal reentry and 58 +/- 49 when one or more accessory pathways were responsible. X-ray exposure times were 14 +/- 14 min and 23 +/- 21 min respectively. Such results would justify the expectation of widened indications of the method.

Left ventricular hypertrophy (LVH) which is a mechanism of adaptation of the heart to hypertension (HT) may become a cardiovascular risk factor independent of the HT which has caused it. Causing the regression of LVH is thus one of the mid-term aims of antihypertensive therapy. Certain antihypertensive drugs are capable of producing an early and durable regression of LVH: methyldopa, beta-blockers, ACEI, calcium blockers. The effect of mass reduction is moderate or doubtful with diuretics, while it is nil or inconstant with vasodilators. The regression of LVH in HT raises various problems: 1) reliability of the measurement technique, 2) inter-individual and inter-drug variations, 3) favourable nature of regression, 4) preventive effect of regression against cardiovascular complications. Finally, in the light of recent studies it appears that early treatment of HT may prevent the onset of LVH.

The authors report another case of successful endocavitary electrocautery in a young woman with Wolff-Parkinson-White syndrome. The pre-excitation was controlled by the administration of two 250 joule electrical shocks applied to the atrial origin of the right anterior bundle. The clinical and laboratory tolerance were satisfactory. Although these results are encouraging, other studies are required in order to define the indications and protocols of electrocautery of accessory pathways.

Fulguration of the bundle of His consists is interrupting or markedly slow-down the atrio-ventricular conduction, in order to suppress or markedly decrease the symptoms related to refractory atrial arrhythmias. With a consecutive series of 128 cases, it is possible to specify the main indications and present a simplified technique, using Josephson's catheter. At 3 months, the results are as follows: 3rd degree atrio-ventricular block in 80 p. cent of the cases, 1st degree atrio-ventricular block in 10 p. cent, with failure in 10 p. cent of the cases. The immediate complications are rare and benign. Late complications are essentially related to the type of cardiac stimulation offered to the patient. The ventricular stimulation with dependent frequency (particularly on ventilation), enables most patients to return to a normal activity.

The new anti-arrhythmic agent flecainide was compared in a single-blind cross-over study to arabogalactane quinidine sulfate in the treatment of stable chronic extrasystole, using a fixed twice-daily dose protocol. Results were assessed by the Holter method. 12 patients (7 men and 5 women) with an average age of 56.5 were selected on the basis of stable and essentially ventricular extrasystole (VES) in 11 cases, and essentially atrial extrasystole (AES) in the remaining case. All patients however had some VES and 6 had some AES, and 5 patients had bursts of VES. The protocol provided for four sequences lasting one week each: one fixed, for selection, and the other three random, flecainide (375 mg), quinidine (660 mg), or placebo (2 doses). Data on each were recorded for Holter analysis. Statistical comparison of results was performed by studying variances on an equilibrated block. Comparison between the selection and placebo sequences showed the stability of the arrhythmia whatever its type. Against ectopic complexes as a whole, only flecainide had significant activity (p less than 0.01). Against AES, both compounds were active (p less than 0.05), quinidine more than flecainide (-73%/63%: a non-significant difference). Only flecainide was active against VES (-88.5%). Quinidine did not significantly reduce VES (-56%).(ABSTRACT TRUNCATED AT 250 WORDS)

Various studies have established the increase of sudden death in hypertensive patients with left ventricular hypertrophy (LVH). In order to specify its most important factors, an electrophysiological study consisting of Holter recording (HR) and programmed ventricular stimulation (PVS), was performed in 24 patients with hypertension: 12 with LVH and 12 without LVH, on ultrasonography. In all patients, coronary angiography was normal. The results are the following: 1) LVH increases the ventricular vulnerability, this arrhythmogenic substrate and its stability are explored by PVS; 2) HR and PVS are not correlated, therefore HR does not explore the arrhythmogenic substrate of LVH, but rather the potential triggering factors of severe rhythm disorders; 3) it has not been possible to evaluate the role of the autonomous nervous system in this study; 4) finally, a significant correlation was found between the degree of anatomical hypertrophy of the LV and the duration of the interval AH.

Propafenone, an anti-arrhythmic medication recently introduced in class lc, was tested in a multicentric open study including 3,687 patients (mean age: 60 years), presenting a supra ventricular (n = 2,146, 59 p. cent), nodal (n = 351, 10 p. cent) or ventricular (n = 1,613, 44 p. cent) arrhythmia, in order to study its efficacy and tolerance. After exclusion of the patients on whom there was a contra-indications to the use of anti-arrhythmic drugs, Propafenone was administered orally, on a long-term basis, at the usual dose of 600-900 mg per 24 hours. The efficacy and tolerance were evaluated according to the usual clinical and paraclinical criteria (EKG, Holter) on the 15th day, then every month during the treatment period. The efficacy of the treatment was evaluated as very good in 54 p. cent of the cases, good in 25 p. cent of the cases, average in 8 p. cent of the patients and non-existent or non significant for 13 p. cent of the patients. Electrocardiographic alterations under Propafenone are already described: CF, PR, QRS. A cardiac undesirable side effect occurred 102 times, most often a sinus bradycardia type (n = 26), atrio-ventricular conduction disorders (n = 22) or intraventricular conduction disorders (n = 26), disorders of cardiac decompensation (n = 10) or arrhythmogenic effect (n = 18). Other side effects are gastro-intestinal in nature (taste alterations, nausea, vomiting, gastralgia) for 23 p. cent of the patients treated, neuro-sensorial in origin (dizziness, visual disorders, tremors) for 13 p. cent of the patients or of another nature for 5 p. cent of patients.(ABSTRACT TRUNCATED AT 250 WORDS)

251 untreated patients with mild to moderate hypertension were included in a multicenter study aimed 1) to detect arrhythmias (24-H Holter recording) and 2) to assess the efficacy of sotalol on blood pressure and possible arrhythmias. Patients with coronary heart disease or previously documented arrhythmias were excluded. Atrial arrhythmias such as premature beats, fibrillation, flutter and paroxysmal atrial tachycardia were detected in 16% of patients. Monomorphic ventricular premature contractions (VPCs) (Lown I and II) were detected in 41% of patients and polymorphic VPCs or duplets/triplets (Lown III and IV) in 14%. A correlation seems to exist between the level of hypertensive cardiopathy, judged on electrocardiographic data (Tarazi classification), age of patients and severity of arrhythmias. Sotalol was administered during 2 months at a mean dose of 160 mg per day. The treatment was effective on blood pressure and arrhythmias (82% improvement of severe VPCs) and the drug was well tolerated. It was difficult to conclude if these good results are due to the betablocking properties or specific class II antiarrhythmic effects of sotalol or to the combined activity.