[Arrhythmic profiles evaluated by Holter's technique in sick sinus syndrome]

The aim of this study was to evaluate in a group of patients with sick sinus syndrome: 1) Characteristics of arrhythmia on Holter monitoring. 2) Value of Holter monitoring to select patients for pacemaker implantation.

Department of Cardiology in a Central Hospital.

In 40 patients (27 men and 13 women, aged 37 to 83 years) Holter monitoring during a 24-hour period was performed. According to the arrhythmia profiles four groups of patients were considered: group A--with severe sinus bradycardia; group B--with sinus bradycardia associated to sinoatrial exit block or to sinus pauses; group C--characterized by the bradycardia-tachycardia syndrome and group D--defined by the finding of atrial fibrillation with a slow ventricular response. Symptoms and the presence of structural heart disease were evaluated.

In this patients population, 24 patients had coronary artery disease and/or hypertensive heart disease. A severe sinus bradycardia was found in 14 patients (group A) and in other 11 patients it was accompanied by sinoatrial exist block of sinus pauses (group B); 12 patients had the bradycardia-tachycardia syndrome (group C) and periods of atrial fibrillation with a slow ventricular response were found in 3 other patients (Group D). Nonspecific clinical pattern was observed in this population.

Holter monitoring was important to the diagnosis of sick sinus syndrome and for posterior definitive pacemaker implantation. Coronary artery disease and/or hypertensive heart disease were the main pathologies found in this study, being the severe sinus bradycardia and the bradycardia-tachycardia syndrome the principal manifestations of the sick sinus syndrome.