[Carotid sinus syndrome. Contribution of arterial pressure monitoring to intracavitary electrophysiological exploration].

A prospective study based on intracavitary electrophysiological exploration coupled with invasive arterial pressure monitoring was conducted in 245 patients aged 70.2 +/- 13 years who had experienced syncopes and/or lipothymias of uncertain origin. The study showed that 63 patients (25.7 p. 100) had carotid sinus syndrome (CSS). The syndrome was of the vagal type (cardiac inhibition) in 27 p. 100 of the cases, of the depressor type (vasodepression) in 22 p. 100 of the cases and mixed in 51 p. 100 of the cases with the two types of pathological response: electrophysiological and haemodynamic. Compared with the remaining 182 patients, these 63 patients were more frequently male (63.5 p. 100, p less than 0.01), of the same age (71.7 years, NS) and more symptomatic, meaning that syncopes occurred in 80 p. 100 of the cases and that their number per patient was higher (2.92, p less than 0.01). A predisposing factor (usually a vagal predominance) was found in 26.9 p. 100 of the cases. In 30 p. 100 of the patients CSS was associated with a sinus node disease or with disorders of atrioventricular conduction. Another haemodynamic abnormality often associated with CSS was a more pronounced (-38.7 mmHg, p less than 0.01) and more frequent (68 p. 100, p less than 0.01) pacemaker effect. 62 p. 100 of patients with mixed CSS had an increase in systolic arterial pressure during vagogenic manoeuvres with DDD mode stimulation as compared with the VVI mode stimulation.(ABSTRACT TRUNCATED AT 250 WORDS)