Registro Brasileiro de Marcapassos: Escolha do Modo de Estimulação no ano de 1999

Brazilian pacemaker register (RBM) is a nationwide database to collect data about all permanent pacemaker procedures performed in Brazil. It is a task force composed of the Health Ministry, Pacemaker Companies and Medical Society. This is a survey reporting the 6th complete year of operation. From January 1st, 1999 to December 31st, 1999, 11.048 surgical procedures for permanent cardiac pacing were performed: 8141 initial implants (73.7%) and 2907 re-operations (26.3%). Single chamber pacemakers were implanted in 6779 patients (61.4%) and dual chamber in 4258 (38.6%). Only 99 atrial single chamber pacemakers were implanted (0.7%). It was possible to detect some factors that had influenced the pacing mode choice for ventricular (VVI) or dual chamber (DC) pacing: 1) the Brazilian region where the procedure was performed; 2) the age of the patient; 3) the functional class for Heart Failure (NYHA) and the preoperative EKG finding. Regional Influence: Ventricular pacemakers were more prevalent in all regions except the central-west where the DC / VVI ratio was 1.5: 1. In all other regions the VVI / DC ratio ranged from 1.3 to 2.0: 1. Age: Atrioventricular pacemakers were preferred for patients from 21 to 60 yrs. (DC / VV ratio range = 1.7:1 and 1.3:1, respectively for ages 21 to 40 and 41 to 60 yrs.). In all other age classes ventricular pacing mode was prevalent. Heart Failure: Ventricular pacemakers were the choice in classes II, III and IV (VVI / DC ratio = 1.2: 1 for class II, 1.5 : 1 for class III and 1.9: 1 in class IV). In class I patients, more dual chamber pacemakers were implanted (DC / VVI ratio = 1.4: 1). Pre-operative EKG Finding: Only sinus syndrome patients received more dual chamber pacemaker than ventricular (DC / VVI ratio = 2.1:1). In all other types of conduction disturbances, more ventricular pacemakers were implanted than dual chamber: in 2nd degree AV block the VVI / DC ratio was 1.2:1, in 3rd AB block it was 1.8: 1 and in atrial flutter / fibrillation patients 10: 1. Other Factors: Gender, preoperative symptoms and etiology of conduction disturbance were not related to pacing mode choice.