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Over the past 30 years, treatment paradigms for atrial fibrillation (AF) patients have changed dramatically. Before 1989, and the publication of the CAST trial results, the primary objective was to maintain or restore sinus rhythm. In the following 20 years, the management of AF patients has focused on the prevention of thrombo-embolic events (with the confrontation of aspirin and oral anticoagulants), and on the debate between rhythm control and rate control. In 2010, the objectives are to reduce symptoms and improve quality of life, to prevent thrombo-embolic complications, and, if possible, to reduce mortality. New anticoagulants will soon be available. Ablative techniques are becoming current practice in selected patients, and the new antiarrhythmic agent dronedarone has shown remarkable clinical results in the ATHENA trial. Overall, ablative techniques can be used in younger patients with paroxysmal or persistent AF refractory to medical treatment a rate control strategy is appropriate in permanent AF, or as second line treatment in patients with other forms of AF.

Antithrombotic treatment is a crucial challenge in the management of patients with atrial fibrillation (AF). It is the only treatment which can decrease mortality in relation with AF. It can also prevent the first cause of dependency in elderly: stroke. Vitamin K antagonists are the more potent drugs to reduce the risk of ischemic stroke in patient with AF. Aspirin, unfractioned heparine or low molecular weight heparin and thienopyridine can also play a role in the antithrombotic therapy in special situations.

Background —The long-term efficacy of atrial fibrillation (AF) detection and R-wave synchronization are critical safety requirements for the development of an implantable atrial defibrillator (IAD) for treatment of AF. Methods and Results —The long-term efficacy of the Metrix IAD for AF detection and R-wave synchronization was tested in 51 patients. The mean duration of follow-up was 259±138 days (72 to 613 days). AF detection tests were performed 2240 times during observed operation with 100% specificity and 92.3% sensitivity for differentiation between sinus rhythm and AF; 2219 episodes and their electrograms stored in the device during AF detection were analyzed. The positive predictive value of the AF detection algorithm was 97.4% (lower 95% confidence limit [CL], 94.5%) in the out-of-hospital setting. A total of 242 435 R waves were analyzed for R-wave synchronization. Of these, 49% were marked for synchronized shock delivery, 82% of sinus rhythm and 36% of AF R waves, respectively. All shock markers were properly synchronized and within the R wave (overall synchronization accuracy, 100%; lower 95% CL, 99.999%). Overall, 3719 shocks have been delivered via the IAD with no instance of unsynchronized shock delivery or any episode of proarrhythmia. The observed proarrhythmic risk was 0%, with an estimated maximum proarrhythmic risk of 0.084% per shock (95% upper CL). Conclusions —The Metrix IAD can appropriately detect AF with a high specificity and sensitivity and reliably synchronize within a suitable R wave for shock delivery to minimize the risk of ventricular proarrhythmia.

Over the past 30 years, treatment paradigms for atrial fibrillation (AF) patients have changed dramatically. Before 1989, and the publication of the CAST trial results, the primary objective was to maintain or restore sinus rhythm. In the following 20 years, the management of AF patients has focused on the prevention of thrombo-embolic events (with the confrontation of aspirin and oral anticoagulants), and on the debate between rhythm control and rate control. In 2010, the objectives are to reduce symptoms and improve quality of life, to prevent thrombo-embolic complications, and, if possible, to reduce mortality. New anticoagulants will soon be available. Ablative techniques are becoming current practice in selected patients, and the new antiarrhythmic agent dronedarone has shown remarkable clinical results in the ATHENA trial. Overall, ablative techniques can be used in younger patients with paroxysmal or persistent AF refractory to medical treatment a rate control strategy is appropriate in permanent AF, or as second line treatment in patients with other forms of AF.

Antithrombotic treatment is a crucial challenge in the management of patients with atrial fibrillation (AF). It is the only treatment which can decrease mortality in relation with AF. It can also prevent the first cause of dependency in elderly: stroke. Vitamin K antagonists are the more potent drugs to reduce the risk of ischemic stroke in patient with AF. Aspirin, unfractioned heparine or low molecular weight heparin and thienopyridine can also play a role in the antithrombotic therapy in special situations.

To describe the management of patients with atrial fibrillation (AF) and to study consistency with guidelines on management of AF.Observational study on a random sample of cardiologists from a French national database. Each cardiologist had to recruit the first five patients meeting inclusion criteria (patients diagnosed with AF between January 2004 and one month before inclusion and accepting the collection of their medical data).Between December 2006 and January 2207, 1789 patients aged 71 on average have been recruited by 481 cardiologists. Fifty-one percent were diagnosed with paroxysmal, 15% with persistent and 33% with permanent AF. Restoration of sinus rhythm was preferred in forms considered as paroxysmal or persistent forms whereas control of the ventricular rate was more frequent in AF considered as permanent. Overall, therapeutic guidelines are applied in practice, despite a frequent use of amiodarone in patients with no associated heart disease. Prevention of thromboembolism was observed in 88% of the patients.FACTUEL is the biggest observational study on AF ever conducted in France. The therapeutic strategies used by the cardiologists are consistent with the objectives of preventing thromboembolism and controlling heart rhythm and/or rate. In most cases, the treatment used is consistent with the therapeutic guidelines.

Atrial vulnerability reflects the ability of the atrium to fibrillate. ISAV (Ischemic stroke and atrial vulnerability) is a French epidemiological registry whose main goal is to assess the evolution modalities of patients in whom an electrophysiological study of the atrium has been performed. A group of 269 patients with a history of non elucidated ischemic stroke and an electrophysiological study of the atrium performed in a mean delay of 3 months after the stroke has been included. Their mean age at the time of the stroke was 55 +/- 15.8 years. The electrophysiological study has measured the effective refractory period of the atrium, the locoregional right intra-atrial conduction time, the index of latent atrial vulnerability and assessed the inductibility. The mean delay between the date of the stroke and the date of the last news was 4.4 +/- 2.8 years. We observed 12 deaths and 11 patients presented during the follow up a spontaneous atrial arrhythmia and 17 a recurrence of stroke. If we consider the occurrence of the 28 combined events (atrial arrhythmia and/or stroke), it is not correlated with the presence of an atrial septal defect nor with the existence of an atrial vulnerability. On the contrary this occurrence is correlated with tobacco consumption and/or arterial hypertension; 82% of patients have these risk factors versus 54% of patients without events (p = 0.004). This association is not significant in patients younger than 55 years.

During these last years, several therapeutic strategies trials have been performed in atrial fibrillation: the goal was to compare the rhythm control strategy (restoration and maintenance of sinus rhythm) to the rate control strategy (slowing of heart rate in atrial fibrillation). The most important of these different trials is the AFFIRM study. The main conclusion of this trial is that rate control can be chosen in first intention and not only in case of failure of the rhythm control strategy. These results can not be applied to 2 categories of patients: on one hand patients with heart failure and on the other hand young patients without cardiopathy in whom the strategy of rhythm control and sinus rhythm maintenance, mainly by class I antiarrhythmic drugs, remains the better choice.

The news concerning anticoagulant therapy is very rich. It was also keenly awaited in view of the real imperfection of antivitamin K drugs on which the present strategy of prevention of thromboembolic risk related to atrial fibrillation is based. The new anticoagulants have differing targets identified from the physiological mechanism of coagulation and the physiopathology of thrombosis.

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 fraction30% and the fact of having received an appropriate shock were predictive of cardiac mortality; and an arrhythmic storm was predictive of sudden death.

The long-term efficacy of atrial fibrillation (AF) detection and R-wave synchronization are critical safety requirements for the development of an implantable atrial defibrillator (IAD) for treatment of AF.The long-term efficacy of the Metrix IAD for AF detection and R-wave synchronization was tested in 51 patients. The mean duration of follow-up was 259+/-138 days (72 to 613 days). AF detection tests were performed 2240 times during observed operation with 100% specificity and 92.3% sensitivity for differentiation between sinus rhythm and AF; 2219 episodes and their electrograms stored in the device during AF detection were analyzed. The positive predictive value of the AF detection algorithm was 97.4% (lower 95% confidence limit [CL], 94.5%) in the out-of-hospital setting. A total of 242 435 R waves were analyzed for R-wave synchronization. Of these, 49% were marked for synchronized shock delivery, 82% of sinus rhythm and 36% of AF R waves, respectively. All shock markers were properly synchronized and within the R wave (overall synchronization accuracy, 100%; lower 95% CL, 99.999%). Overall, 3719 shocks have been delivered via the IAD with no instance of unsynchronized shock delivery or any episode of proarrhythmia. The observed proarrhythmic risk was 0%, with an estimated maximum proarrhythmic risk of 0.084% per shock (95% upper CL).The Metrix IAD can appropriately detect AF with a high specificity and sensitivity and reliably synchronize within a suitable R wave for shock delivery to minimize the risk of ventricular proarrhythmia.

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.

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.

OBJECTIVE--To investigate the quantitative relationship, if any, between signal averaged electrocardiographic variables and echocardiographically determined left ventricular mass in hypertensive subjects. DESIGN--Cohort analytic prospective study. SETTING--University hospital. SUBJECTS--50 hypertensive subjects selected consecutively from inpatients. Patients older than 75 years, with underlying cardiac disease, with inconclusive echocardiograms with bundle branch block, or in atrial fibrillation were excluded. INTERVENTIONS--Antihypertensive therapy involving 41 patients was continued. MAIN OUTCOME MEASURES--Left ventricular mass calculated in accordance with the standards of the Penn convention. Thirteen criteria derived from combinations of signal averaged electrocardiographic X, Y, and Z Frank orthogonal leads, including voltage criteria, duration, and time-voltage integrals of the QRS complex. Four widely used standard electrocardiographic criteria for detection of left ventricular hypertrophy. RESULTS--There was no difference in the values for any of the electrocardiographic variables between patients with (n = 29) and without left ventricular hypertrophy (n = 21). The time-voltage integral of QRS in the horizontal plane was the best signal averaged variable related to left ventricular mass (r = 0.33, P = 0.019); however, the correlation with Rodstein voltage was stronger (r = 0.46, P = 0.0009). A positive correlation was also found between left ventricular indexed mass and Rodstein voltage (r = 0.43, P = 0.0019). Stepwise regression analysis revealed Rodstein voltage as the only predictor of indexed mass (P = 0.0019), and Rodstein voltage (P = 0.0022) and body weight (P = 0.011) as the only independent correlates of left ventricular mass. CONCLUSIONS--The relation between electrocardiographic variables and left ventricular mass or indexed mass is of limited value; signal averaged orthogonal leads do not improve this assessment compared with standard electrocardiographic leads.

Fifteen per cent of cerebrovascular accidents have a cardiac origin, two thirds of which are due to atrial fibrillation (AF). The Framingham study showed the risk of an ischaemic cerebral event to be increased by 5.6 in AF unrelated to rheumatic heart disease and by 17.5 when AF is associated with valvular heart disease. The risk of embolism is higher in elderly subjects and in those with underlying cardiac disease. Other high risk conditions include hypertension, diabetes, hyperthyroidism and cases with echocardiographic changes: left atrial dilatation, pre-thrombotic state or intra-atrial thrombus, atheroma of the ascending aorta. This stratification of risk should be taken into account when deciding on treatment. Conscious of the importance of the risk of embolism in AF, several authors have undertaken, over the last few years, randomised studies of the prevention of thromboembolic complications of AF: the AFASAK, BAATAF, SPAF and SPINAF trials. All showed the unquestionable efficacy of warfarin, even at low doses, at the price of a haemorrhagic risk of less than 2% per year for severe haemorrhages. A more recent study (SPAF II) confirmed the value of aspirin at the dosage of 325 mg/day which would seem to be a good alternative to anticoagulant therapy when this is contraindicated, although aspirin is less effective. The indications for anticoagulant therapy have become clearer since the publication of these results. Anticoagulant therapy is essential in permanent AF whether or not associated with rheumatic heart disease.(ABSTRACT TRUNCATED AT 250 WORDS)