Relationship Between Initial Cardiovascular Structural Changes and Daytime and Nighttime Blood Pressure Monitoring

Abstract

It has been shown that in hypertensive patients the degree of target organ damage correlates more closely with average blood pressure as recorded by ambulatory monitoring (ABPM) throughout 24 h than with clinic blood pressure. We examined a group of 91 clinically healthy subjects, 23 normotensives and 68 hypertensives according to clinic blood pressure. Cardiac anatomy was investigated by echocardiography. As an index of arterial structural changes forearm minimal vascular resistance was calculated from mean arterial pressure and maximal postischemic blood flow, as assessed by venous occlusion plethysmography. The results were correlated to clinic blood pressure or ABPM values (measured by noninvasive ABPM ICR 5200, Spacelabs, Bellevue, CA). Left ventricular mass was correlated more closely with the average blood pressure recorded during 24 h, or during daytime or nighttime periods, than with clinic blood pressure. Minimal vascular resistance was also significantly correlated to ABPM values, but the correlation was similar to that observed with clinic blood pressure. Minimal vascular resistance was significantly correlated to blood pressure variability, as evaluated by the standard deviation of the mean. Minimal vascular resistance and left ventricular mass were higher in a subgroup of patients in whom blood pressure was not significantly reduced during the night. The results of this study confirm that elevated average ABPM values are associated to higher left ventricular mass; in addition, they suggest that increased blood pressure variability may be associated with vascular structural changes, as evaluated by minimal vascular resistance. It remains to be clarified whether cardiac hypertrophy and/or vascular structural changes are a cause or consequence of increased blood pressure values and variability.

Night-time blood pressure patterns and target organ damage: A review

“…Posterior wall thickness > in nondippers (24 † ,31) Atrial/brain natriuretic peptide > in nondippers (58) Left ventricular ejection fraction ↓ in nondippers (49,58) Supraventricular/ventricular ectopies > in nondippers (49,59) QT dispersion/QTc interval > in nondippers (60,61) Systemic vascular resistance ↑ at night in nondippers (62) ↓ at night in dippers (62) Stroke index ↑ at night in nondippers (63) ↓ at night in dippers (63) Cardiac index less of a ↓ at night in nondippers (63) ↓ at night in dippers (63) Cardiac output No difference between nondippers and dippers (24,62) Pulse pressure less of a ↓ at night in nondippers (12,67) ↓ at night in dippers (12,67) Carotid artery intima-media > in nondippers (9,14 (46,(73)(74)(75) Lacunae > in nondippers (6,10) Periventricular hyperintensities > in nondippers (6,10) White matter lesions > in nondippers (76) Previous cerebrovascular event More nondipping in those with previous events (71) Cognitive impairment > in nondippers (79) Dementia > in nondippers (78,81) Memory ↓ in nondippers (82) Sensory motor speed ↓ in nondippers (82) Microalbuminuria > in nondippers (6,27,84,85) *Cardiovascular eve...…”

Evaluation of Subclinical Target Organ Damage for Risk Assessment and Treatment in the Hypertensive Patients

“…Hypertension is the fundamental trigger to the sequence of biologic events that lead to the development of LVH. LVM is more closely related to average 24-h BP (2)(3)(4). Volume load, inotropy, and arterial compliance also are important determinants of the development and the degree of LVH.…”

Night time blood pressure and cardiovascular structure in a middle-aged general population in northern Italy: the Vobarno Study

“…Only few studies have addressed this relation in hypertensive patients, in whom abnormalities in small resistance vessels structure have been previously reported, as related to circadian BP changes. Rizzoni et al 18 observed that minimal vascular resistance was significantly related to ABP values and variability, and that forearm minimal vascular resistance was greater in those patients with a decrease of nocturnal mean arterial pressure of less than 10% of the mean daytime BP. A significantly higher minimal vascular resistance was also demonstrated in 45 hypertensives without a decrease in systolic and diastolic BP during asleep period greater than 10% compared with 45 dipper patients, matched for sex, age, body mass index, smoke and lipids.…”

“…18 It has been recently observed that in hypertensive patients who did not show a decrease of BP during night time the intima media thickness of the common carotid artery was greater as compared with patients with a sleep reduction of BP. 19,20 In the present population-based cross-sectional study, designed to estimate the prevalence of structural changes both in the heart and in the carotid arteries in middle-aged subjects, the carotid intimamedia thickness and the presence of plaque, as well as the presence of LVH, were determined in relation to an altered diurnal BP rhythm, obtained by ambulatory monitoring, before and after correction for other traditional risk factors.…”