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In a given hypertensive patient, clinically overt cardiovascular disease is often preceded by a number of signs of target organ damage at the cardiac, arterial and renal levels. These changes have been collectively defined "pre-clinical cardiovascular disease", and carry a substantially increased risk for future cardiovascular complications. The present article examines the relationship between blood pressure components and target organ damage in essential hypertension. Arterial pressure can be split into a steady component (represented by the mean arterial pressure), which is a measure of the average level of pressure in a given artery, and a pulsatile component (represented by the pulse pressure), which estimates the cyclic oscillations around the mean. All blood pressure components show a positive, linear correlation with left ventricular mass, both in the general population and in patients with essential hypertension. However, the association is significantly stronger for the steady blood pressure components (systolic and mean arterial pressure) than for the pulse pressure. Available data regarding arterial changes suggest that the association is partly different. The majority of available studies show that large-artery intima-media thickening and discrete atherosclerotic plaques are better predicted by pulse pressure than by other blood pressure components, particularly in the elderly. After the age of 60, there is clear-cut evidence for a J-shaped relationship between diastolic blood pressure and arterial thickening or plaques, while for younger age groups the relationship appears to be linear. These data might offer an explanation for the observed superior prognostic value of pulse pressure in the elderly. The relationship between the different blood pressure components and renal damage is more controversial. In summary, pulsatile, cyclic stress (as represented by pulse pressure) appears to be more important in determining arterial changes in hypertensive patients, while steady blood pressure components play a dominant role in the development of hypertensive left ventricular hypertrophy.

To investigate whether the level of clinical blood pressure (BP) may serve to stratify the risk of left ventricular (LV) hypertrophy in essential hypertension regardless of the level of ambulatory BP, we performed 24-hour noninvasive ambulatory BP monitoring and echocardiography in 115 consecutive hypertensive patients who had never been treated before and in 92 normotensive subjects. Hypertensive patients were grouped according to the difference between the observed clinical BP and the predicted value of clinical BP, defined by regressing the observed clinical BP on the 24-hour average of the ambulatory BP: "low" clinical BP group (clinical systolic BP less than = 10 mmHg, diastolic BP less than = 6 mmHg than predicted values), "high" clinical BP group (systolic greater than = 10 mmHg, diastolic greater than = 6 mmHg than predicted values), "intermediate" clinical BP group (values within the above mentioned limits). Ambulatory BP did not show any statistically significant differences between the three groups. LV mass index was higher in hypertensive patients in each of the three groups (including the "low" clinical BP group) as compared with the normotensive group (all p less than 0.01), but did not show any statistically significant difference among the three groups of hypertensive patients, either defined by systolic BP or by diastolic BP. Other indexes of LV anatomy (relative wall thickness, cross-sectional area) showed a similar pattern.(ABSTRACT TRUNCATED AT 250 WORDS)

To investigate whether hospitalization may influence the circadian rhythm of blood pressure (BP), 15 untreated patients with essential hypertension underwent noninvasive ambulatory blood pressure monitoring twice, at home and in the hospital, in a random order, 11 days apart. During the hospital session, which took place on the ninth day of hospitalization, patients were allowed to move freely in the hospital area, to receive visits by friends and relatives and to engage in social activities with other inpatients. Home sessions were performed during a usual working day in 14 of 15 patients. Average 24-hour systolic/diastolic BP was 151/93 mmHg (DS 19/10) at home and 154/93 mmHg (DS 21/7) in the hospital; average daytime (6am-10pm) values were 155/97 mmHg (DS 19/10) at home and 157/96 mmHg (DS 20/5) in the hospital; average night-time (10pm-6am) values were 146/88 mmHg (DS 21/12) at home and 150/89 mmHg (DS 23/10). These values did not show any statistical differences (analysis of variance) due to status (home vs hospital), period or sequence. The hourly BP averages of the hospital recording did not differ significantly from the corresponding averages of the home recording. The correlation between hospital and home 24-hour averages of systolic and diastolic BP was close (r = 0.87 and r = 0.78, respectively; p less than 0.01). The chronobiological analysis (single cosinor) showed a statistically significant circadian rhythm of systolic BP in 10/15 patients at home and in 8/15 patients in the hospital (p = NS), and a statistically significant rhythm of diastolic BP in 9/15 patients at home and in 10/15 patients in the hospital (p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)

To evaluate the difference between the sexes in the echocardiographic indices of left ventricular hypertrophy in essential hypertension, we analysed the results of 24-hour non invasive ambulatory blood pressure monitoring and echocardiography in 195 consecutive untreated hypertensive patients (101 males, 94 females). Patients were divided into 3 age groups: up to 40 years, 41-60 years, and greater than 60 years of age. Clinical blood pressure did not differ between sexes in any of the three groups, while average 24-hour ambulatory systolic and diastolic blood pressure levels were higher in males than in females up to 40 years of age (140/93 vs 129/87 mmHg, p less than 0.01), but not between 41 and 60 years (142/93 vs 141/90 mmHg) nor in those over 60 years of age (151/92 vs 145/91 mmHg). LV mass index was higher in males than in females up to 40 years (93 vs 68 g/m2, p less than 0.01), and between 41 and 60 years (115 vs 90 g/m2, p less than 0.01), but not dissimilar between the sexes over 60 years of age (102 vs 107 g/m2, p = n.s.). In females, LV mass index increased with age (r = 0.33) and body weight (r = 0.38; both p less than 0.01), but none of these relationships was significant in males (r = 0.01 and r = 0.19, respectively). Moreover, all the relations of LV mass to either clinical or ambulatory BP were closer in females than in males. None of the echocardiographic indices of left ventricular systolic function showed statistically significant differences between the sexes in any of the three age groups.(ABSTRACT TRUNCATED AT 250 WORDS)