Abstract Background Oral anticoagulation (OAC) reduces thromboembolic events and mortality in patients with atrial fibrillation (AF). Anticoagulation rates have substantially increased over recent years. Still, a number of patients are not receiving guideline recommended OAC. Purpose To investigate clinical factors and reasoning associated with non-prescription of OAC in a current German registry. Methods The German AFNET 2 registry is a prospective multi-center registry on atrial fibrillation comprising a total of 3491 patients from all levels of medical care (general practitioners, cardiologists, hospitals; enrolment 5/2014 to 3/2016). The registry was conducted in collaboration with the EORP program of the ESC. Here, only patients with non-valvular AF and at least two clinical risk factors for stroke (using CHA2DS2-VASc score) were considered. Results The study population consisted of 2856 patients, 58.4% male, mean age 75.5±7.8 years, mean CHA2DS2-VASc score 4.1±1.5, mean HAS-BLED score 1.8±1.0. Overall, the rate of OAC was 94.3%. 54% of these received Vitamin K antagonists (VKA) and 46% NOAC. 2.3% received antiplatelets only. Patients newly initiated on OAC mostly received a NOAC (82.5% of patients). Anticoagulation rate was lower in elderly patients (age <80 years: 95.0%, age ≥80 years 92.8%, p<0.05). No difference in OAC was seen between men and women (94.1% and 94.6%, respectively). Patients with high bleeding risk (HAS-BLED ≥3) received significantly less OAC than patients at low bleeding risk (95.3 vs 90.6%, p<0.001). Patients on antiplatelet therapy received OAC in only 78.0% compared to patients without antiplatelet therapy in 96.6% (p<0.001). In patients without OAC (n=162 patients), reasons stated for non-prescription of OAC were patient's unwillingness to take OAC (13.6%), physician preference (12.3%), prior bleeding event (10.5%), renal dysfunction (8.6%), frequent falls (5.6%), current anaemia (5.6%), current operation/intervention (4.9%), current bridging with LMW heparin (4.9%), and other reasons (9.3%). Using logistic regression analysis, non-prescription of OAC was strongly associated with antiplatelet therapy (HR=0.082), anaemia (HR=0.41), dementia (HR=0.37), and previous extra- (HR=0.2) or intracranial haemorrhage (HR=0.35). Predictors of OAC use were prior stroke/embolism (HR=2.35), hypertension (HR=2.23), heart failure (HR=1.51), and previous stent implantation (HR=2.12). When considered as a score, a HAS-BLED score ≥3 was strongly associated with non-prescription of OAC (HR=0.51). Conclusions Within registries, the guideline recommended use of OAC is very high in Germany indicating high guideline adherence by prescribing physicians. However, use of antiplatelet therapy was associated with non-prescription of OAC. In addition, a high HAS-BLED score appears to be a relevant argument for withholding proven OAC for stroke prevention in patients with AF. Acknowledgement/Funding BMS Germany; DZHK

For stratification of thromboembolic events in atrial fibrillation (AF), the CHADS2 score has gained wide acceptance. However, the risk of stroke remains significant even in the lower risk groups (CHADS2 scores 0 and 1) where oral anticoagulation is not clearly recommended. For this reason, more elaborated risk stratification has been proposed by recent guidelines of the ESC. The frequency of thromboembolic complications in patients with CHADS2 scores 0 and 1 has therefore been analyzed in the German AFNET registry, a contemporary population of patients with atrial fibrillation. Methods: A total of 9575 patients with atrial fibrillation were enrolled from 2004-2006 in the Central Registry of the German Competence NETwork on Atrial Fibrillation (AFNET). After exclusion of patients with rheumatic valve disease or valve prosthesis, the study population consisted of 8847 patients, mean age 68.3±11.1 years; 38.1% were women. Treatment of patients including decision on oral anticoagulation was at the discretion of the attending physician. Results: Stroke risk stratification by the CHADS2 score assigned 16.2% of patients to "low" risk (score 0), 31.5% (score 1) to "intermediate" risk, and 52.3% to "high" risk (score ≥ 2), indicating that according to the CHADS2-stratification, a total of 47.7% of the 8847 patients would not have a definitive recommendation to use oral anticoagulation. During a mean follow-up of 5.9 years, 395 patients had documented thomboembolic events (ischaemic stroke, TIA, or systemic embolism) with 144 of the patients assigned to CHADS2 score of 0 or 1 (CHADS2 0, 45 patients, CHADS 1, 99 patients). Thus, when stratified by the CHADS2 score, 36.5% of the patients with thromboembolic events were assigned to the low and intermediate stroke risk group. Using the CHA2DS2-VASc score, 30.3% of patients previously classified as CHADS2 0 or 1 would be assigned to CHA2DS2-VASc 1 or ≥2, where oral anticoagulation is the recommended strategy. Conclusion: With 36.5% of the patients with thromboembolic events assigned to the low and intermediate risk group, the CHADS2 score does not provide adequate sensitivity to stratify patients at low risk for stroke. To provide guidance on anticoagulation for patients with CHADS2 scores 0 and 1, the use of a more detailed risk stratification appears to be required, such as the CHA2DS2-VASc score proposed in the recent guidelines of the ESC.

ZusammenfassungVorhofflimmern (VHF) ist die häufigste anhaltende Rhythmusstörung in der täglichen Praxis und trägt ein ca. fünffach erhöhtes Risiko für einen ischämischen Schlaganfall. Um ein aktuelles Abbild von Diagnostik und Behand-lung sowie von langfristigen Komplikationen und Prognose von Patienten mit VHF in Deutschland zu erhalten, wurde 2003 im Kompetenznetz Vorhofflimmern ein Patientenregister etabliert. Erste Ergebnisse weisen daraufhin, dass die Rate der oralen Anti-koagulation mit 67% mit den Ergebnissen anderer europäischer Register vergleichbar ist. Insbesondere ältere Patienten (ab dem 70. Lebensjahr) werden nicht ausreichend mit einer erforderlichen oralen Antikoagulation behandelt. Die klinisch übliche Risikostratifizierung nach dem CHADS2-Score hat in der klinischen Praxis nur einen limitierten Einfluss auf die Entscheidung zur Antikoagulation. Unterschiedliche Antikoagulationsraten in spezialisierten Zentren gegenüber nicht kardiologischen Einrichtungen sind nur zum Teil durch Unterschiede in Altersstruktur und Begleiterkrankungen zu erklären. Entsprechend wird die Antikoagulation bei VHF zur Prävention ischämischer Schlaganfälle weiter unzureichend genutzt.

Atrial fibrillation is the most common clinically relevant arrhythmia and carries a five-fold increase in embolic stroke risk. In order to obtain an impression of current diagnostic and therapeutic decisions as well as long term complications and prognosis in patients with atrial fibrillation in Germany, a patient registry was established in 2003 within the German AFNET. Initial results indicate that the overall rate of oral anticoagulation is comparable to results from other registries on atrial fibrillation in Europe. Most notably, patients aged 70 years and older frequently do not receive a required oral anticoagulation. The clinical stroke risk stratification scheme, CHADS(2)-score, has only a minor impact on the decision to provide anticoagulation in daily clinical practice. The observed differences in anticoagulation rate in specialized cardiac care centres as compared to non-specialized centres could only be in part explained by differences in age of the patients and concomitant health conditions. It is concluded that oral anticoagulation remains underused in the prevention of ischemic stroke in atrial fibrillation in Germany.

Das Kompetenznetz Vorhofflimmern (AFNET) ist ein bundesweites interdisziplinäres Forschungsnetzwerk, das seit 2003 vom Bundesministerium für Bildung und Forschung (BMBF) gefördert wird. Ziel des AFNET ist es, die Behandlung von Vorhofflimmern, der häufigsten klinisch bedeutsamen Herzrhythmusstörung, nachhaltig zu verbessern. Das AFNET hat ein deutschlandweites Register mit 9582 Patienten aufgebaut, mit dem eine Bestandsaufnahme von Diagnostik, Therapie, Verlauf und Komplikationen von Vorhofflimmern in Deutschland erfolgt. Patienten mit Vorhofflimmern weisen typischerweise eine Vielzahl prädisponierender Erkrankungen wie Hypertonie, Herzklappenfehler, koronare Herzkrankheit und Diabetes mellitus sowie ein fortgeschrittenes Alter auf. Die ersten analysierten Daten zeigen, dass die orale Antikoagulation der Patienten mit Vorhofflimmern in hoher Übereinstimmung mit den Leitlinien durchgeführt wird. Untersucht werden zudem in kontrollierten Studien Fragen nach der adäquaten Therapiedauer mit Antiarrhythmika nach Kardioversion und der Wert medikamentöser Maßnahmen zur Vermeidung der Entwicklung eines arrhythmogenen Substrats mit dem Ziel der Prävention von Vorhofflimmerepisoden. Weitere Registerprojekte dienen der Verlaufs- und Erfolgskontrolle sowie der Qualitätssicherung interventioneller Therapieverfahren von Vorhofflimmern, die mit kathetergeführten Ablationstechniken und chirurgisch-ablativen Verfahren in den letzten Jahren eine rasche Verbreitung erfahren haben. Das AFNET war auch Plattform für 2 internationale Konsensuskonferenzen, in denen die gewonnenen Erkenntnisse in die Weiterentwicklung der Behandlungsstandards eingebracht wurden.

The German Competence Network on Atrial Fibrillation (AFNET) is a national interdisciplinary research network funded by the Federal Ministry of Education and Research (BMBF). AFNET was initiated in 2003 and aims at improving treatment of atrial fibrillation (AF), the most frequent sustained cardiac arrhythmia. AFNET has established a nationwide patient registry on diagnostics, therapy, course and complications of AF in Germany. The data analyzed to date demonstrate that patients with AF are likely to have multiple co-morbidities, such as hypertension, valvular heart disease, coronary artery disease, diabetes mellitus and advanced age. Oral anticoagulation is provided to the majority of patients in accordance with the recommendations given by guidelines. Further areas of research deal with the optimal duration of antiarrhythmic therapy following electrical cardioversion of atrial fibrillation and the value of strategies to prevent arrhythmogenic changes, such as fibrosis in the atria, for prevention of further episodes of atrial fibrillation. Additional registry projects were established for patients with catheter-based interventional therapy of atrial fibrillation and surgical ablation to define success, complications and long term results of these recently developed procedures more clearly. Data and insights gathered from these projects were used to further develop standards of care in two international conferences.

Vorhofflimmern ist die häufigste anhaltende Rhythmusstörung und mit einer erheblichen Morbidität und Mortalität assoziiert, insbesondere aufgrund eines 4- bis 5fach erhöhten Risikos thrombembolischer Schlaganfälle. Die bedeutendsten Risikofaktoren für sein Auftreten sind arterielle Hypertonie, Herzinsuffizienz und koronare Herzerkrankung. Die Prävalenz in der Allgemeinbevölkerung liegt bei etwa 1% mit einer stark altersabhängigen Zunahme, 84% der Patienten sind alter als 65 Jahre. Aufgrund der demografischen Entwicklung sowie der zunehmenden Prävalenz der Risikofaktoren wird mit einer Verdopplung der Prävalenz von Vorhofflimmern über die nächsten 50 Jahre gerechnet. Es ist mit einer ungünstigen Prognose verknüpft, die Mortalität von betroffenen Patienten ist etwa um das 2Fache erhöht, wobei Frauen im Vergleich zu Männern eine bis zu 2,5fach höhere Mortalität auf weisen. Neuere Studien legen nahe, dass auch Patienten mit idiopathischem Vorhofflimmern eine belastete Prognose haben. Aufgrund der hohen Rate asymptomatischer Patienten, deren Vorhofflimmern oft erst bei Komplikationen erkannt wird, muss von einer höheren Prävalenz ausgegangen werden als derzeit angenommen. Früherkennung und primärpräventive Strategien werden künftig eine wachsende Bedeutung erlangen.

Introduction: Patients with implantable cardioverter defibrillators (ICD) critically depend on correct functioning of their system. The aim of this study was to determine the incidence and clinical presentation of transvenous ICD lead failures during long-term follow-up.Methods and Results: The study group consisted of 261 consecutive patients who received Medtronic right ventricular polyurethane transvenous leads (models 6884, 6966, 6936) between 1990 and 1998 as part of an abdominal (n = 70) or pectoral (n = 191) ICD system. During mean follow-up of 4.0 +/- 2.6 years, 31 patients (12%) developed a lead-related sensing failure with oversensing of artifacts. All failures except two were compatible with an insulation defect and occurred late after ICD placement (6.0 +/- 1.8 years after implant). Lead survival decreased from 98% at 4-year follow-up to only 62% at 8-year follow-up. Lead survival was not related to patient age, sex, venous lead implantation route, or device implantation site. In 26 (87%) of 31 patients, a sensing defect resulted in inappropriate detection of ventricular fibrillation and subsequent delivery of 3 +/- 3 (range 1-11) inappropriate shocks in 19 (61%) of 31 patients. Device interrogation showed artifacts classified as nonsustained ventricular tachycardia in 21 patients, 40 +/- 43 days before clinically relevant failure of the system. One patient with a subclavian crush syndrome required resuscitation because of undersensing of true ventricular fibrillation.Conclusion: Transvenous polyurethane ICD leads showed a high rate of lead insulation failure late after implantation with frequent inappropriate shock deliveries. Close follow-up is mandatory in patients with these leads. Automated device control features with patient alert function integrated into new devices may contribute to early detection of lead failure.