[Heart rate and arrhythmias in long-term ECG in patients with coronary disease and dilated cardiomyopathy with...

Heart-rate (HR) and arrhythmias (AR) are influenced by the vegetative balance. This cannot be measured during daily life at present. Otherwise HR and AR can be detected with a high accuracy using the Holter-Method (HM). Therefore we investigated the relationship of HR, AR and left-ventricular function (LVF) in patients with coronary heart disease (CHD: 342 HM; normal LVF 33%, moderate reduced 33%, reduced 35%) and dilative cardiomyopathy (DCM: 225 HM, LVF normal 13%, moderate reduced 39%, reduced 48%), with special emphasis on the problem, whether tachycardia during chronic congestion will stimulate AR (AR due to an increased sympathic tone) or will suppress AR (overdrive suppression). Furthermore we evaluated, whether patients with a loss of the circadian pattern (CP) of HR or AR, who demonstrated an uniform high HR (due to the enhanced sympathic tone), were on higher risk of dying than other collectives. HM were analysed using the computer-supported "Multipass-Scanning" system. The decreasing LVF coincides with an increase in HR and a loss of HR-CP (i.e. dHR-day-night greater than or equal to 10 b.p.m.). The amount of the HR-CP depends on the mean HR during day in the manner of a direct relationship. The prevalence of premature ventricular ectopics (PVC) increases with decreasing LVF from 39 to 53% (CHD) and from 47 to 63%. A positive circadian pattern of the PVC exists in 60% of CHD and in 84% of DCM, which also decreases with the LVF to 54 vs. 52%. Independent from a CP in two thirds of the patients VA were stimulated and in one third suppressed with a worsening of the LVF. The phenomenon of an overdrive suppression of VA starts with a HR of 90 b.p.m. and higher. The 40% mortality in patients with an uniform (day and night) high HR (greater than 90 b.p.m.) was significantly higher than in other collectives (10%).