LEFT-VENTRICULAR MASS INDEX NEGATIVELY CORRELATES WITH HEART-RATE-VARIABILITY IN ESSENTIAL-HYPERTENSION

To investigate the relationship between alterations of the autonomic n ervous activity and left ventricular mass index in essential hypertens ive patients, 24-h power spectral analysis of R-R intervals was perfor med using Holter electrocardiography. Fifty-three patients (mean age, 58.0 +/- 13.1 years; 30 men and 23 women) participated.; The urinary e xcretions and plasma levels of catecholamines were also determined. Po wer spectral analysis of R-R interval was performed every 10 min by th e maximum entropy method to obtain the low frequency band (LFB; 0.04 t o 0.15 Hz), which is an index of both parasympathetic and sympathetic nervous activities, and the high frequency band (HFB; 0.15 to 0.4 Hz), which reflects parasympathetic nervous activity. LFB and HFB were ave raged every hour to obtain hourly LFB and HFB levels. Total LFB and HF B were calculated as the summation of 24-h LFBs and HFBs. Left ventric ular mass index showed a significant negative correlation with total L FB (r = -0.466, P < .001) and total HFB (r = -0.319, P < .02). These f indings suggest that the level of end-organ damage correlates with neu ronal alteration in essential hypertension.