In order to ensure the best treatment quality with a high success rate and a low rate of complications, the position of the German Cardiac Society on catheter ablation of atrial fibrillation (AF) is that the standards of performing this therapeutic intervention need to be critically evaluated and adapted on a regular basis. This is particularly warranted in view of the rapidly increasing numbers of centers and cardiologists offering catheter ablation of AF. The present position paper therefore reviews currently available scientific data, addresses the indications for and complications of catheter ablation of AF, presents latest technological developments and finally discusses the mandatory requirements for centers at which catheter ablation of AF is performed in terms of personnel, equipment, premises, structure and organization.

This article aims to give an overview over important articles in the field of implantable cardioverter defibrillator (ICD) therapy in 2012. Important publications concern analyses on therapy efficacy and safety of the subcutaneous ICD, gender-specific differences in the complication rate and prognosis after ICD implantation, the necessity of intraoperative testing of the defibrillation threshold and the impact of preventive measures to reduce ICD therapies on prognosis after device implantation. The relevance of the study findings for daily clinical practice is briefly discussed.

In diesem Artikel soll eine Übersicht über wichtige, publizierte Arbeiten auf dem Gebiete der Therapie mit dem implantierbaren Kardioverter/Defibrillator (ICD) im Jahre 2012 gegeben werden. Wesentliche Arbeiten betrafen Analysen zur Therapieeffektivität und -sicherheit des subkutan implantierbaren ICD, zu geschlechtsspezifischen Unterschieden in der Komplikationsrate und Prognose nach ICD-Implantation, zur Notwendigkeit der intraoperativen Testung der Defibrillationsschwelle und zur Beeinflussung der Prognose nach ICD-Implantation durch Verhinderung von ICD-Schockentladungen. Die Relevanz der Studienergebnisse für den klinischen Alltag wird jeweils kurz diskutiert.

Defibrillatorelektroden der Firma St. Jude Medical vom Typ Riata® und Riata ST® zeigen ein erhöhtes Auftreten von Isolationsdefekten, wobei die inneren, separat isolierten Leiter durch den Elektrodenkörper nach außen treten können („inside-out fracture“). Die genaue Inzidenz von Riata®-Elektrodenproblemen ist nicht klar. Nach neuen Daten von US-amerikanischen und kanadischen Registern scheint sie bei 2–4% pro Jahr in den ersten 5 Jahren zu liegen und höher für Riata®-8F-Elektroden zu sein.

Patients with an implantable cardioverter defibrillator (ICD) may experience loss of consciousness. Electromagnetic interference (EMI) may trigger undesired or inhibit necessary therapy in patients with an ICD. Therefore, questions about personal or professional activities for ICD patients arise. Restricting driving or other personal activities has adverse effects on the patient's quality of life. The national Societies of Cardiology provide recommendations for ICD patients concerning driving of motor vehicles. Patients with an ICD that is implanted prophylactically do not have to refrain from driving after recovery from the implantation procedure. Patients with arrhythmias are classified into different groups depending on the risk of recurrence of tachycardias and symptoms. Commercial driving is not allowed for patients with an ICD in Germany except for those with a prophylactic indication without a history of arrhythmias. Those patients may drive small cars but no trucks or busses. Guidelines for medical fitness in commercial or military flying are regulated by the Joint Aviation Authorities (JAA) and ventricular tachycardias are a contraindication for both. Fortunately, loss of consciousness is not dangerous in most jobs. Strong sources of EMI can occur at special workplaces. Patients have to be advised and tested individually concerning their risk for EMI at their employment site before returning safely. Modern life exposes to an increasing amount of EMI. Intact household devices usually do not interfere with ICDs. Mobile phones may interfere with implanted devices. Interaction can be minimized by special precautions like maintaining a distance of minimum 10 cm between mobile phone and ICD. Electronic surveillance systems work differently and have the potential to interact with devices. Patients should be advised to pass those systems with avoiding longer exposure. The presence of an ICD is presently a contraindication for undergoing magnetic resonance imaging (MRI) because of a high risk of destruction of the system with even potential harm to the patient. High-frequency application for electrocautery devices or ablation is possible under certain precautions that have to be planned before. There is a high sensitivity of ICD systems to ionizing radiation with defect of the devices after a cumulative dose > 5 Gy.

Background: Implantation of an additional pace/sense (P/S) lead is commonly used in patients with implantable cardioverter/defibrillators (ICDs) to overcome P/S defects of integrated defibrillation leads (HV‐P/S leads). No information is available about the clinical outcome and the incidence of complications in these patients.

Cardiac resynchronization therapy (CRT) is now considered an established therapy for patients with chronic heart failure in the presence of a wide QRS complex. Though proarrhythmic effects have been described in a few cases, CRT did not increase the frequency of ventricular tachyarrhythmias in prospective studies. In patients on CRT therapy, persistent atrial fibrillation sometimes converts back to sinus rhythm, possibly dependent on the duration of atrial fibrillation.

AIMS External electrical cardioversion is the method of choice to terminate persistent atrial fibrillation. Whether the type of shock electrode affects cardioversion success is not known. We tested whether hand-held steel electrodes improve cardioversion outcome with monophasic or biphasic shocks when compared with adhesive patch electrodes. METHODS AND RESULTS Two hundred and one consecutive patients with persistent atrial fibrillation (147 male, mean age 63+/-1 years, duration of atrial fibrillation 6.3+/-1 months) were randomly assigned to cardioversion using either a sinusoidal monophasic or a truncated exponential biphasic shock wave form. The first half of patients were cardioverted using adhesive patch electrodes, the second half using hand-held steel paddle electrodes, and all patients using an anterior-posterior electrode position. Paddle electrodes successfully cardioverted 100/104 patients (96%) and patch electrodes 85/97 patients (88%, P=0.04). This effect was comparable to that of biphasic shocks: biphasic shocks cardioverted 102/104 patients (98%) and monophasic shocks 83/97 patients (86%, P=0.001). A beneficial effect of paddle electrodes was observed for both shock wave forms. After cross-over from an ineffective monophasic to a biphasic shock, cardioversion was successful in 198/201 (98.5%) patients. Unsuccessful cardioversion after cross-over (3/201 patients) only occurred with patch electrodes (P=0.07). CONCLUSION Hand-held paddle electrodes increase success of external cardioversion of atrial fibrillation in this trial. This increase is of similar magnitude as the increase in cardioversion success achieved with biphasic shocks. A combination of biphasic shocks, paddle electrodes, and an anterior-posterior electrode position renders outcome of external cardioversion almost always successful (104/104 patients in this trial).

Background— Brugada syndrome is an arrhythmogenic disease characterized by an ECG pattern of ST-segment elevation in the right precordial leads and an increased risk of sudden cardiac death as a result of ventricular fibrillation. Controversy exists with regard to risk stratification and therapeutic management, particularly in asymptomatic individuals. Methods and Results— A total of 212 individuals (mean age, 45±6 years) with a type 1 Brugada ECG pattern were studied. Of these, 123 (58%) were asymptomatic, 65 (31%) had ≥1 syncope of unknown origin, and 24 (11%) had to be resuscitated because of ventricular fibrillation. In 125 individuals (59%), a spontaneous type 1 ECG was recorded. In the remaining, drug challenge with a class I antiarrhythmic agent unmasked a Brugada ECG. The mean ST elevation was 2.3±1.2 mm in symptomatic patients and 1.9±1.5 mm in asymptomatic individuals ( P =0.04). During a mean follow-up of 40±50 months, 4 of the 24 patients (17%) with aborted sudden cardiac death and 4 of 65 (6%) with a prior syncope had a recurrent arrhythmic event, whereas only 1 of 123 asymptomatic individuals (0.8%) had a first arrhythmic event. Four of 9 patients with arrhythmic events during follow-up were not inducible during programmed electrical stimulation. A previous history of aborted sudden death or syncope and the presence of a spontaneous type 1 ECG were predictors of adverse outcome. Conclusions— The present study reports data on a large population of individuals with a type 1 Brugada ECG pattern with the longest follow-up reported so far. A very low incidence of severe arrhythmic events, particularly in asymptomatic individuals, was found during follow-up. In the presence of very few arrhythmic events on follow-up, programmed electrical stimulation showed very little accuracy in predicting outcome.

OBJECTIVES The purpose of this study was to evaluate retrospectively a single-center experience with the use of ICIs in patients with long QT syndrome (LQTS) concerning outcome, complications, and optimal programming.BACKGROUND Use of implantable card i overter-defibrillator (ICD) in patients with congenital LQTS is controversial but is generally accepted in high-risk patients.METHODS We enrolled 27 symptomatic patients with LQTS undergoing ICD therapy (QTc 540 +/- 64 ms (1/2); 85% female, 63% cardiac arrest; 33% syncope despite beta-blockers; 4% with severe phenotype) and 81 genotyped patients with LQTS undergoing conventional drug therapy (28 LQT1, 39 LQT2, ILQT3, 13 LQT5). During a mean follow-up of 65 +/- 34 months, one death occurred in the ICD group that was not LQTS related. A total of 178 appropriate shocks were observed in 10/27 patients (37%), mostly in Survivors of cardiac arrest (in 58% of cardiac arrest patients vs. in 20% of non-cardiac arrest patients).RESULTS In a logistic regression analysis, only QTc interval (121/178 shocks (68%) for QTc > 500 ms (1/2)) and "survived cardiac arrest" were prognostic for ICD shocks. In 30% of patients in the ICD group, multiple shocks occurred and could be reduced after increase of antibradycardia pacing rate, adding beta-blocker therapy, or starting the rate-smoothing algorithm (average 7.1 shocks before to 0.75 shocks after additional intervention annually).CONCLUSION ICD therapy is a safe and useful tool in high-risk patients with LQTS. QTc interval and cardiac arrest survivors were prognostic factors for appropriate ICD shocks. The results of this large single-center experience suggest that beta-blockers should always be added to ICD therapy. In addition, some patients might benefit from additional antibradycardia pacing, prolonged detection time, and a rate-smoothing algorithm to prevent recurrent episodes.

Die kardiale Resynchronisationstherapie hat sich in den letzten 10 Jahren zu einem etablierten Verfahren zur Therapie der fortgeschrittenen Herzinsuffizienz bei Patienten mit Linksschenkelblock entwickelt.

Implantation of a transvenous device in patients with a tricuspid valve replacement or a complex congenital heart disease with no access to the right ventricle represents problems. The lack of access to the right ventricle might preclude transvenous placement of a defibrillation lead at ICD implantation. A young patient (21 years) with a history of severe chest trauma with rupture of the tricuspid valve as well as the right coronary artery and consecutive inferior myocardial infarction was initially treated with tricuspid valve replacement (St Jude Medical artificial prosthesis, 33 mm) and a bypass graft to the right coronary artery. Four years later, the patient was admitted with a hemodynamically not tolerated ventricular tachycardia (VT: CL 250 ms, LBBB, left axis). The VT could be reproduced during electrophysiological testing. An ICD was implanted subpectorally in combination with a transvenous active fixation ICD lead. The transvenous ICD lead was placed via a guiding catheter into a coronary sinus branch (middle cardiac vein). Acceptable pacing and sensing values could be obtained. The defibrillation threshold was 25 J. In conclusion transvenous ICD lead implantation into a side branch of the coronary sinus in combination with a pectorally implanted "active can" ICD device seems to be an alternative approach. This approach may avoid implantation of additional subcutaneous defibrillation leads or even thoracotomy for ICD implantation.

Aim In experimental studies, nonexcitatory electrical stimulation delivered at the time of absolute myocardial refractoriness resulted in cardiac contractility modulation (CCM) with improved systolic function. This study reports the initial experience with CCM in patients with chronic heart failure.Methods and results Twenty-five patients, 23 mates, with a mean age of 62 9 years and drug-refractory NYHA class III heart failure were assigned to CCM-generator implantation. The underlying heart disease was idiopathic dilated cardiomyopathy in 12 patients and coronary heart disease in 13 patients. Acute efficacy of CCM with 7.73-V stimuli delivered via two right ventricular leads was evaluated by measuring the time derivative of left ventricular pressure (dP/dt). After implantation, the CCM generator was activated for 3 h daily over 8 weeks.In 23/25 patients the CCM system was implanted successfully. Heart failure significantly improved from NYHA class III to class 11 in 15 patients and to class I in 4 patients (p < 0.000001), left ventricular ejection fraction improved from 22 +/- 7% to 28 +/- 8% (p = 0.0002), and the Minnesota Living with Heart Failure Score improved from 43::E 22 to 25 18 (p = 0.001). The 6-min walk test increased from 411 86 to 465 81 m (p = 0.02). Nine patients (39%) had intermittent sensations associated with CCM delivery. There were two (8%) non-device-related deaths during follow-up.Conclusions These preliminary data indicate that CCM by delivery of intermittent nonexcitatory electrical stimuli is a promising technique for improving ventricular systolic function and symptoms in patients with drug-refractory NYHA class III heart failure. (C) 2004 Published by Elsevier Ltd on behalf of The European Society of Cardiology.

OBJECTIVESWe assessed the clinical efficacy of single-site left ventricular (LV) pacing and determined the impact of baseline conduction delay severity on the magnitude of benefit.BACKGROUNDMultisite biventricular pacing can improve heart failure (HF) symptoms in patients with an intraventricular conduction delay by resynchronizing abnormal ventricular contractions and improving LV systolic function.METHODSEighty-six patients with at least New York Heart Association functional class II HF, chronic LV systolic dysfunction, normal sinus rhythm, and a QRS interval over 120 ms were implanted for atrial-synchronized LV pacing. The single-blinded, randomized, controlled, crossover study stratified patients 1:1 by the baseline QRS interval into long (QRS > 150 ms) and short (QRS 120 to 150 ms) groups, which were compared during a three-month period of active (univentricular) pacing and a three-month period of inactive (ventricular inhibited) pacing. The primary end point was peak oxygen consumption (Vo(2)) followed by anaerobic threshold, distance walked in 6 min, and quality-of-life questionnaire score.RESULTSTwelve patients were withdrawn before randomization and 17 could not complete both study periods. The short QRS group did not improve in any end point with active pacing. For the long QRS group, peak Vo(2) increased 2.46 ml/min/kg (p < 0.001), the anaerobic threshold increased 1.55 ml/min/kg (p < 0.001), the distance walked in 6 min increased 47 m (p = 0.024), and the quality-of-life score improved 8.1 points (p = 0.004).CONCLUSIONSLeft ventricular pacing significantly improves exercise tolerance and quality of life in patients with chronic HF, LV systolic dysfunction, and a QRS interval over 150 ms. (J Am Con Cardiol 2003;42:2109-16) (C) 2003 by the American College of Cardiology Foundation.

Background: Patients resuscitated from ventricular tachyarrhythmias benefit from implantable cardioverter-defibrillators (ICDs) as opposed to medical treatment. Patients with increased QRS duration receiving an ICD in the presence of heart failure are at greatest risk of cardiac death and benefit most from ICD therapy. Objective: To determine whether an increased QRS duration predicts cardiac mortality in ICD recipients. Design: Consecutive patients with heart failure in New York Heart Association functional class III were grouped according to QRS duration (< 150 ms, n = 139, group 1; v ⩾ 150 ms, n = 26, group 2) and followed up for (mean (SD)) 23 (20) months. Patients: 165 patients were studied (80% men, 20% women); 73% had coronary artery disease and 18% had dilated cardiomyopathy. Their mean age was 62 (10) years and mean ejection fraction (EF) was 33 (14)%. They presented either with ventricular tachycardia (VT) or ventricular fibrillation (VF). Main outcome measures: Overall and cardiac mortality; recurrence rates of VT, fast VT, or VF. Results: Mean left ventricular EF did not differ between group 1 (33 (13)%) and group 2 (31 (15)%). Forty patients died (34 cardiac deaths). There was no difference in survival between patients with EF > 35% and ⩽ 35%. Cardiac mortality was significantly higher in group 2 than in group 1 (31.3% at 12 months and 46.6% at 24 months, v 9.5% at 12 months and 18.2% at 24 months, respectively; p = 0.04). The recurrence rate of VT was similar in both groups. Conclusions: Within subgroups at highest risk of cardiac death, QRS duration—a simple non-invasive index—predicts outcome in ICD recipients in the presence of heart failure.