ABSTRACT
This study correlates variables derived from blood pressure (BP) and heart rate (HR) monitoring with the degree of left ventricular structural changes in essential hypertension. Forty patients with mild-to-moderate hypertension according to World Health Organization criteria underwent 24-hour ambulatory monitoring. Echocardiographic (posterior wall and interventricular septum thickness, left ventricular mass) or ECG (SV1 + RV5) indices of hypertrophy were significantly (p less than 0.01) correlated (positive correlations) with derivatives of BP monitoring (mean systolic and diastolic BP values) but not with HR derivatives. Echocardiographic indices of dilatation (left ventricular end-diastolic volume and diameter) were significantly (p less than 0.01 to less than 0.001) correlated (negative correlations) with derivatives of HR monitoring (mean HR values, mainly during the night) but not with BP derivatives. It is concluded that in essential hypertension, left ventricular hypertrophy depends on mean 24-hour systolic and diastolic BP values, whereas left ventricular dilatation appears to be more prominent in patients with bradycardia mainly during the night.
Subject(s)
Cardiomegaly/physiopathology , Heart Rate/physiology , Hypertension/physiopathology , Adult , Dilatation, Pathologic/physiopathology , Echocardiography , Electrocardiography, Ambulatory , Female , Humans , Male , Middle Aged , Monitoring, Physiologic , Multivariate Analysis , Radiography, ThoracicABSTRACT
The urinary iodine excretion, expressed as the iodine/creatinine (I/Cr) ratio, was correlated with the serum T4 and TSH levels in persons with a relatively constant iodine intake for at least 6 months. It was found that the group with an I/Cr ratio of 151-200 micrograms/g had on average the lowest serum TSH and the highest serum T4 level. The differences in serum TSH from the other groups were statistically significant, whereas the differences in serum T4 were not. It is concluded that an I/Cr ratio of 151-200, corresponding to an iodine intake of about 200 micrograms/day, is associated with the lowest TSH stimulation of the thyroid gland in man and probably represents the optimal conditions for its function.
