[Clinical manifestations of extrinsic and intrinsic sinus node dysfunction (functional and organic factors)]

We analysed the clinical data of 206 patients (pts) with sick sinus syndrome (group S). All the population was divided into two group; pts with normal (104 pts, group S1) and abnormal (102 pts, group S2) "intrinsic" properties of sinus node (SN). Intrinsic properties was defined as normal if intrinsic heart rate was normal and corrected sinus node recovery time after pharmacological heart denervation (propranolol 0.2 mg/kg body weight, atropine 0.04 mg/kg body weight) was no longer than 422 ms. In whole group S, in 131 pts we found organic heart disease (coronary heart disease, n = 102, hypertensive disease, n = 12, mitral valve prolapse, n = 10, history of myocarditis or mild mitral or aortic valve stenosis, n = 7). In groups S1 and S2 coronary heart disease was found in 31 and 71 pts, hypertensive disease in 6 and 6 pts respectively. All the patients with mitral valve prolapse were found in group S1. In 75 pts sinus node disease (SSS) was the only pathological finding, they were divided into group IS1 (n = 51) and IS2 (n = 24) according to the intrinsic properties of the SN.

1. In clinical practice sinus node dysfunction seems to be more frequent in men than in women, 2. In the large group of patients with sick sinus syndrome we analysed in this paper in about 36% we did not find any other diseases of the heart.(ABSTRACT TRUNCATED AT 250 WORDS)