Guías de práctica clínica de la Sociedad Española de Cardiología en marcapasos

[Implantable pacemakers and defibrillators: implications for anesthesia and perioperative management]

The technological complexity of implantable devices for managing arrhythmias, specifically pacemakers and defibrillators, has increased spectacularly since their introduction a few decades ago. A growing number of patients with these devices are undergoing surgery and it is therefore essential to understand how they work and what the real associated risks are. Manuals and reference works on anesthesia may provide little information on these devices and their perioperative management. It is no longer satisfactory to place a magnet over these devices during surgery and assume that this action will protect the patient from the possible effects of electromagnetic interference. This review examines the basic principles and operation of implantable pacemakers and defibrillators, the relevant nomenclature, and the sources and effects of electromagnetic interference; the current recommendations for the perioperative management of patients fitted with these devices are also discussed.

[Clinical safety and efficacy of single-chamber atrial pacing in sick sinus syndrome: long-term follow-up]

INTRODUCTION AND OBJECTIVES

Although atrial pacing is a more physiological mode of stimulation in sinus node dysfunction, the pacing modes most often are used DDD and VVI. The aim of our study was to demonstrate that AAI/AAIR pacing is effective and safe by analyzing the complications and mortality of this pacing mode in a long-term follow-up study.

PATIENTS AND METHOD

Between 1982 and 2000 definitive AAI-mode pacemakers were implanted for sinus node dysfunction in mode AAI in 160 patients. We analyzed the clinical characteristics, evolution, and complications of the AAI pacing mode during a follow-up of 5.4 4.5 years.

RESULTS

The sample was made up of 104 women and 56 men with an average age of 72 12 years. During follow-up, it was necessary to change the pacing mode for symptomatic bradycardia in 11 patients (annual incidence 1.2%), which was caused by second or third-degree atrioventricular block in 7 patients (annual incidence 0.8%), and chronic atrial fibrillation with bradycardia in 4 patients (annual incidence 0.4%). During follow-up, atrial arrhythmias occurred in 32 patients (annual incidence 3.7%), stroke in 4 patients (annual incidence 0.4%), and 27 patients (annual incidence 3.1%) died.

CONCLUSIONS

The AAI/AAIR pacing mode was safe and effective in sinus node dysfunction, with a low percentage of pacing changes required for progression to atrioventricular block, low incidence of atrial arrhythmias, stroke and low mortality during long term follow-up.