[Scientific results of the pacemaker register: possibilities and limits]. / Wissenschaftliche Ergebnisse des Herzschrittmacherregisters: Möglichkeiten und Grenzen.

The German obligatory external quality assurance for pacemaker implantation generates a large database giving an almost complete review of in-patient pacemaker interventions since 2001. Publications on lead fixation, age and gender dependency of pacemaker indications, choice of pacing mode and complication rates as well as investigations into the causes of lead dysfunction prove that the database is basically suitable for health service research. In contrast to pacemaker registries of other European countries the focus on in-patient operations, missing product specifications and the absence of patient follow-up largely limits the scientific potential of the database. It is greatly hoped that these limitations will be overcome by cross-sectional and longitudinal quality assurance within the next years.

[Avoidance of ventricular pacing in patients with sinus node disease or intermittent AV block]. / Ventrikuläre Stimulationsvermeidung bei Patienten mit Sinusknotenerkrankung oder intermittierendem AV-Block.

In patients with frequent right ventricular stimulation, worsening of heart failure and atrial fibrillation may occur. Avoidance of unnecessary right ventricular pacing is a major requirement for pacemaker selection and programming in patients with sinus node disease or intermittent AV block. In dual chamber pacemakers this goal can be achieved by programming a long AV delay or an AV delay hysteresis. Algorithms that allow AAI pacing in a dual chamber pacing mode and change to DDD mode in case of high degree AV block are a new attempt to avoid unnecessary right ventricular pacing. The article describes various strategies to avoid unnecessary ventricular pacing and discusses their advantages and disadvantages.

Long term complications in single and dual chamber pacing are influenced by surgical experience and patient morbidity.

OBJECTIVE: To determine how short and long term complication rates after pacemaker implantation are influenced by patient morbidity, operator experience, and choice of pacing system. DESIGN: Retrospective analysis of 1884 patients who received VVI (n = 610), VDD (n = 371), or DDD devices (n = 903) between 1990 and 2001. Follow up period was 64 (34) months. The influence of age, sex, coronary artery disease, myocardial infarction, reduced left ventricular (LV) function, right ventricular (RV) dilatation, atrial fibrillation, device type, and operator experience on operation time and complication rate were analysed. RESULTS: Operation time was prolonged in patients with coronary artery disease, inferior myocardial infarction, reduced LV function, and RV dilatation. Implantation of DDD pacemakers prolonged operation time, particularly among operators with a low or medium level of experience. The overall complication rate was 4.5%. Sixty seven per cent of these complications occurred within the first three months. Complication rate was increased by age, reduced LV function, and RV dilatation. Implantation of DDD systems led to a higher complication rate (6.3%) than implantation of VVI (2.6%) or VDD pacemakers (3.2%). These differences were present only among operators with a low or medium level of experience. CONCLUSIONS: Operation time and complication rate increased with age, impaired LV function, and RV dilatation. Complication rates were higher with DDD than with VVI or VDD implantation and were excessive among inexperienced but not experienced operators.

[Preventive pacemaker stimulation in atrial fibrillation]. / Präventive Schrittmacherstimulation bei Vorhofflimmern.

Preventive pacing algorithms and the use of alternative or multifocal pacing sides are new approaches for treatment of paroxysmal atrial tachyarrhythmias. However, present data are not sufficient to define a new indication for pacemaker implantation in patients with refractory atrial fibrillation. Yet, preventive pacing should be predominantly performed either in patients with an established pacemaker indication or during controlled study projects. In patients undergoing cardiac surgery, biatrial overdrive pacing using temporary epicardial wires can be recommended for prevention of postoperative atrial fibrillation.