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1.
Blood pressure (BP) predictors of left ventricular mass index (LVMI) were studied in 40 healthy normotensive (71.4 ±4.4 years) and 31 hypertensive (73.5 ±4.8 years) elderly community-dwelling subjects using short-axis cardiac cine magnetic resonance imaging and 24-h ambulatory BP monitoring. Mean night-time BPs were calculated from the average of readings during sleep and mean daytime BPs were calculated from the remaining recordings. The hypertensive subjects were all receiving anti-hypertensive therapy with angiotensin-converting enzyme (ACE) inhibitors, calcium-channel blockers, beta-blockers or diuretics. Nocturnal systolic BP was a strong predictor of LVMI in both normotensive ( β = 0.38, p = 0.02) and treated hypertensive ( β = 0.39, p = 0.03) subjects. By contrast, daytime systolic BP was a weaker predictor of LVMI in the treated hypertensives ( β = 0.36, p = 0.04) and did not predict LVMI in the normal subjects ( β = 0.27, NS). Nocturnal BP may partly explain the increase in LVMI with ageing in subjects thought to be normotensive on the basis of daytime clinic BP recordings.  相似文献   

2.
The absence of nocturnal fall in blood pressure (BP) is named as nondipper status, which has been shown to be an additional risk factor for the development of left ventricular hypertrophy and cardiovascular events in several high-risk groups. The aim of this study was to determine the influences of the nondipper status and nocturnal blood pressure loads on left ventricular mass index (LVMI) in renal transplant recipients. A total of 35 nondiabetic renal transplant recipients were included into the study. A 24-h ambulatory blood pressure monitoring (ABPM) was performed for all recipients. The nondipper status was defined as either an increase in night-time mean arterial pressure (MAP) or a decrease of no more than 10% of daytime MAP. LVMI was measured by using two-dimensional guided M-mode echocardiography. The night-time systolic blood pressure (SBP) load was defined as the percentage of the time, during which SBP exceeded 125 mmHg during night time. The nondipping was common among renal transplant recipients, of whom 60% were nondipper in our study. LVMI was significantly higher in the nondipper group vs the dipper group (133 +/- 35 g/m(2) vs 109 +/- 26 g/m(2), P = 0.04). A fall in MAP at night time was 14.5 +/- 4.3% in the dipper group, while it was 1.4 +/- 6.1% in the nondipper group (P < 0.001). On stepwise multiple regression analysis, night-time SBP load and haemoglobin were independent predictors of LVMI (R(2) = 0.53). In conclusion, nondipping is common after renal transplantation. Night-time SBP load and low haemoglobin are closely related to the increase in LVMI in renal transplant recipients. ABPM may be a more useful tool in optimizing treatment strategies to reduce cardio-vascular events in renal transplant recipients.  相似文献   

3.
Exercise blood pressure response is related to left ventricular mass   总被引:1,自引:0,他引:1  
An exaggerated SBP response to exercise has been associated with increased left ventricular (LV) mass in some but not all studies. A total of 43 women and 34 men, aged 55-75 years, without evidence of cardiovascular disease, with a mean resting BP of 142+/-9/77+/-8 mmHg had their BP measured at rest and during maximal treadmill exercise. LV mass was measured using magnetic resonance imaging. LV mass was adjusted for lean body mass, which was assessed by dual energy X-ray absorptiometry. LV mass was within the normal range for the majority of the subjects. Among the resting and exercise BP indices, maximal SBP was the strongest correlate of LV mass (r=0.41, P<0.05). In multivariate analysis, maximal SBP was independently associated with LV mass after adjustment for lean body mass and gender, explaining 3% of the variance (P<0.05). Maximal exercise SBP is a modest but still independent predictor of LV mass in older persons with normal LV mass. These results raise the possibility that the SBP response to maximal exercise is an early marker of LV hypertrophy.  相似文献   

4.
QT interval is prolonged in hypertensive individuals, although the factors responsible for this increase are not completely understood. We questioned whether enhanced left ventricular mass (LVM) or increased systemic blood pressure represents the principal factor determining QT prolongation in the period of development of hypertension and left ventricular hypertrophy (LVH) in spontaneously hypertensive rats (SHR). In 12-and 20-week-old SHR (SHR12 and SHR20) and age-matched normotensive Wistar-Kyoto rats (WKY12 and WKY20), arterial systolic blood pressure (sBP) was measured using tail-cuff technique. Orthogonal Frank ECG was registered in anaesthetized animals in vivo, and bipolar ECG was measured in spontaneously beating isolated hearts in vitro. Progressive increase of sBP and LVM resulted in significant QT prolongation in SHR20 as compared to WKY12, WKY20, and also to SHR12 in vivo (WKY12: 82 +/- 9 ms, WKY20: 81 +/- 9 ms, SHR12: 88 +/- 15 and SHR20: 100 +/- 10, respectively; p < 0.05) but not in isolated hearts (WKY20: 196 +/- 39 ms and SHR20: 220 +/- 55, respectively; NS). In whole animals, QT duration was positively related to sBP (r = 0.6842; p < 0.001) but not to LVM (r = 0.1632, NS) in SHR20. The results suggest that QT prolongation in SHR developing hypertension and LVH depends on blood pressure rather than increase in LVM. In this period, myocardial hypertrophy is probably the predisposition for QT prolongation, but the significant change manifests only in the presence of elevated systemic factors.  相似文献   

5.
BACKGROUND: Evidence suggests that "glucose effectiveness," (SG) or the effect of glucose per se to enhance net glucose disposal, may be at least as important as the insulin sensitivity index (SI) in the assessment of glucose tolerance. Our objective was to study the relationship of SG and SI parameters to left ventricular mass in a group of untreated, nondiabetic, and nonobese subjects recently diagnosed with stage I or high-normal blood pressure (BP). METHODS: In this sample of subjects, among whom the expected prevalence of insulin resistance is low, we assessed SG and SI parameters using the intravenous glucose tolerance test and minimal model analysis. We also measured left ventricular mass (LVM) index and diastolic function by echocardiography. RESULTS: We observed a strong relationship between SG and LVM index (r = -0.61, P <.0001). Patients with left ventricular hypertrophy (LVH) had lower SG than those without LVH (0.1114 +/- 0.04 v 0.2088 +/- 0.08 x 10(-1). min(-1), P <.001). In contrast, patients below the lowest quartile of the SG parameter distribution had higher LVM index (126.4 +/- 23.1 v 94.8 +/- 22.3 g/m(2), P <.001) and also had higher prevalence of LVH than the other patients (P <.0001). The SI related only to diastolic dysfunction, suggesting that SG may be an earlier marker of LVH than SI in hypertension. CONCLUSION: In this sample of nonobese and glucose-tolerant subjects with an early stage of hypertension, SG but not SI was related to LVM.  相似文献   

6.
Appropriateness of left ventricular (LV) mass to cardiac workload can be evaluated by the ratio of observed LV mass to the value predicted for an individual's gender, height(2.7), and stroke work at rest (%PLVM). It is unclear which pathophysiological factors are associated with inappropriately high LV mass in hypertensive subjects. Adequate LV mass was defined by the 90% confidence interval (73% to 128%) of the distribution of %PLVM in 393 normal-weight normotensive subjects. In 185 hypertensive subjects (aged 56+/-11 years; 60% male, 29% black), according to %PLVM, 164 (88%) had adequate LV mass, 16 (9%) had inappropriately high LV mass (%PLVM >128%), and 5 (3%) had %PLVM <73% (low LV mass). Age, gender, smoking habit, proportion of never-treated subjects, total cholesterol, triglycerides, and creatinine levels did not differ significantly between subjects with adequate and inappropriately high LV mass. Body mass index, fasting glucose, and proportion of black subjects were higher (all P<0.05), while HDL cholesterol was lower (P<0.05) in subjects with inappropriately high LV mass. Blood pressure at the echocardiogram was comparable between subjects with adequate and inappropriately high LV mass, but the latter group had higher ambulatory blood pressure (P<0.01). Subjects with inappropriately high LV mass also had higher aortic root dimension and LV relative wall thickness and relatively lower LV systolic performance than those with adequate LV mass (all P<0.001). Larger aortic root diameter and lower systolic function were also found in hypertensive subjects with inappropriate LV hypertrophy compared with those with adequate LV hypertrophy. In an exploratory case-control study that compared subjects with low %PLVM with age-matched counterparts with adequate LV mass, low %PLVM was associated with lower body mass index, more favorable metabolic profile, and higher LV myocardial contractility. Higher body mass index, larger aortic root, and black race were independent correlates of increased %PLVM. Thus, in arterial hypertension, levels of LV mass inappropriately high for gender, cardiac workload, and height(2.7) are associated with higher body mass index, higher ambulatory blood pressure, larger aortic root diameters, and relatively low myocardial contractility.  相似文献   

7.
OBJECTIVES: We aimed to investigate left ventricular (LV) morphology and function in normotensive offspring of subjects with essential hypertension (familial trait - FT), and to determine the association between LV mass and determinants of LV diastolic function and endothelium-dependent (NO-mediated) dilation of the brachial artery (BA). MATERIALS AND METHODS: The study encompassed 76 volunteers of whom 44 were normotonics with FT aged 28-39 (mean 33) years and 32 age-matched controls without FT. LV mass and LV diastolic function was measured using conventional echocardiography and tissue Doppler imaging (TDI). LV diastolic filling properties were assessed and reported as the peak E/A wave ratio, and peak septal annular velocities (E(m) and E(m)/A(m) ratio) on TDI. Using high-resolution ultrasound, BA diameters at rest and during reactive hyperaemia (flow-mediated dilation--FMD) were measured. RESULTS: In subjects with FT, the LV mass index was higher than in controls (92.14+/-24.02 vs 70.08+/-20.58); p<0.001). Offspring of hypertensive families had worse LV diastolic function than control subjects (lower E/A ratio, lower E(m) and E(m)/A(m) ratio; p<0.001). In subjects with FT, FMD was decreased compared with the controls (6.11+/-3.28% vs 10.20+/-2.07%; p<0.001). LV mass index and E(m)/A(m) ratio were associated with FMD (p<0.001). CONCLUSIONS: In normotensive individuals with FT, LV morphological and functional changes were found. We demonstrated that an increase in LV mass and alterations in LV diastolic function are related to endothelial dysfunction.  相似文献   

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Blood pressure has been shown to decrease in response to hospital admission. Several parameters including the decline of sympathetic nervous activity and negative sodium balance have been shown to be involved in this phenomenon. We investigated genetic influence on office BP and BP after hospitalization. One hundred and sixty-three men from the general population, free from antihypertensive medication, were enrolled in the present study. They stayed at the hospital for general medical check-up. BP was measured on the day of admission, and again the following day. Mean systolic blood pressure was significantly decreased after hospitalization from 117.3 +/- 9.9 mmHg to 115.3 +/- 12.8 mmHg (p=0.042). Subjects with DD+ID genotype showed a significantly higher systolic blood pressure after hospitalization than that of subjects with genotype II. There were no genotype specific differences in diastolic blood pressure or changes in blood pressure by the administration. In summary, systolic blood pressure after hospitalization was significantly higher in normotensive male subjects who possessed the D allele of ACE I/D polymorphism.  相似文献   

10.
Left ventricular muscle mass is increased in the presence of large body size, high blood pressure and obesity, but the relative contributions to ventricular mass of these and other factors have not been elucidated. Accordingly, echocardiographic left ventricular mass in unmedicated employed adults (162 normotensive, 145 borderline hypertension and 317 with established essential hypertension) was related to height, weight, lean body mass, body mass index, systolic and diastolic blood pressure, age, gender, race and 24 h urinary sodium and potassium excretion. In the total population, body mass index, systolic blood pressure and height were the most significant (p less than 0.0001) independent correlates of left ventricular mass, whereas gender and age made smaller contributions. In each normotensive and hypertensive subgroup, body mass index and height remained highly significant independent predictors of left ventricular mass, systolic blood pressure became a weaker predictor (0.001 less than p less than 0.02) and only among patients with established hypertension was diastolic blood pressure a weak independent determinant (p less than 0.05) of ventricular mass. The increase in left ventricular mass attributable to obesity was due to eccentric hypertrophy because end-diastolic relative wall thickness was similar in obese and nonobese subjects in each blood pressure group. Thus obesity, as measured by body mass index, is as important a potential determinant of left ventricular muscle mass as is systolic blood pressure and it is of greater statistical significant in an adult employed population than is diastolic blood pressure, height, gender, age or dietary sodium intake.  相似文献   

11.
Electrocardiographic evidence of left ventricular hypertrophy (ECG-LVH) has a grave prognostic significance in hypertensive patients. The purpose of our study was to assess whether ECG-LVH is more strongly associated with home-measured blood pressure (BP) than with clinic BP, and whether the correlation between home BP and ECG-LVH increases with the number of home measurements performed. We studied a representative sample of the general adult population (1989 subjects 45-74 years of age) in Finland. Subjects included in the study underwent a clinical interview, electrocardiography and measurement of clinic BP (mean of two clinic measurements) and home BP (mean of 14 duplicate home measurements performed during 1 week). Home BP correlated significantly better than clinic BP with the Sokolow-Lyon voltage (home/clinic systolic: r=0.23/0.22, P=0.60; diastolic: r=0.17/0.12, P=0.009), Cornell voltage (systolic: r=0.30/0.25, P=0.004; diastolic: r=0.21/0.12, P<0.001) and Cornell product (systolic: r=0.30/0.24, P=0.001; diastolic r=0.22/0.14, P<0.001) criteria of ECG-LVH. The correlation between home BP and ECG-LVH increased slightly with the number of home measurements, but even the mean of the initial two home BP measurements correlated equally well (systolic BP), or better (diastolic BP) with ECG-LVH than did clinic BP. In conclusion, home BP measurement allows us to obtain a large number of measurements that have a strong association with ECG-LVH. Our data support the application of home BP measurement in clinical practice.  相似文献   

12.
OBJECTIVE: To assess the relationships between the level and variability of ambulatory blood pressure and left ventricular and arterial function. METHOD: We related 24 h ambulatory systolic blood pressure (SBP) and diastolic blood pressure (DBP), measures of their variability and clinic blood pressures to echocardiographic measures of left ventricle geometry and systolic function, total peripheral resistance, and the pulse pressure: stroke volume ratio as a measure of arterial stiffness in 58 normotensive and 222 unmedicated hypertensive adults. RESULTS: For hypertensive patients and for the entire population, awake and home ambulatory as well as technician-measured DBP were negatively related to left ventricle midwall fractional shortening (MWS) and to MWS as a percentage of the value predicted for end-systolic stress (afterload-corrected MWS), with inconsistent relations with SBP. Similarly, the SD and coefficient of variation of awake ambulatory DBP, but not SBP, were negatively related to both measures of left ventricle midwall function. Hypertensive patients in the lowest quintile of afterload-corrected MWS had similar physician-measured but higher ambulatory awake and home as well as technician-measured DBP, but not SBP, and higher SD of awake SBP and DBP than did those with higher afterload-corrected MWS. Ambulatory awake, home, and sleep as well as technician-measured DBP, but not SBP, were positively related to total peripheral resistance at rest whereas all components of ambulatory SBP, but not DBP, were positively related to the resting p;ulse pressure: stroke index ratio, a measure of arterial stiffness. We detected no relation between the nocturnal dip in blood pressure and any measure of left ventricular or arterial function or left ventricle geometry. Finally, left ventricle mass and relative wall thickness were related most strongly to awake and home ambulatory SBP whereas left ventricular relative wall thickness was also related to the SD of awake DBP. CONCLUSION: For this population of predominantly hypertensive unmedicated adults, ambulatory blood pressures during waking hours and at home were related to left ventricular and arterial function, the strongest relations being negative ones of DBP with left ventricular midwall function and positive ones of ambulatory DBP with peripheral resistance and ambulatory SBP with a measure of arterial stiffness. For this population the nocturnal dip of blood pressure was not related to measures either of cardiovascular function or of left ventricular structure.  相似文献   

13.
OBJECTIVE: Inappropriate left ventricular mass (LVM) and microalbuminuria predict cardiovascular events in hypertension. We attempted to evaluate the relationship between inappropriate LVM and albuminuria in hypertensive patients. PATIENTS AND METHODS: Four hundred and two nondiabetic, untreated patients with primary hypertension were studied. The appropriateness of LVM to cardiac workload was calculated by the ratio of observed LVM to the predicted value using the reference equation. Albuminuria was evaluated by the urinary albumin to creatinine ratio. RESULTS: The deviation of LVM from the predicted value was positively related to albuminuria (P < 0.0001). Multiple regression analysis showed that albuminuria (0.0182), pulse pressure (P < 0.0001) and left ventricular hypertrophy (LVH) (P < 0.0001) were the only independent predictors of observed/predicted LVM. When subjects were divided into subgroups on the basis of the presence/absence of inappropriate LVM, patients with inappropriate LVM showed higher urinary albumin excretion (P < 0.0001), regardless of potential confounding factors, including LVH (analysis of covariance, P = 0.0453), and higher prevalence of microalbuminuria (P = 0.0024) compared to those without it. Analogous results were obtained by looking at the study patients on the basis of the presence of micro- or normoalbuminuria. Indeed, patients with microalbuminuria showed higher prevalence of inappropriate LVH compared to other left ventricular geometries (appropriate LVH and absence of LVH) (P < 0.0001). After adjusting for confounders, microalbuminuria entailed a three- and five-fold greater risk of having appropriate and inappropriate LVH, respectively. CONCLUSIONS: Inappropriate LVM is associated with albuminuria in hypertension. These data strengthen the role of microalbuminuria as an indicator of high cardiovascular risk.  相似文献   

14.
BACKGROUND: We investigated whether mean heart rate (HR(24)) and blood pressure (BP) parameters during 24-h ambulatory BP monitoring (ABP) are independent or additive markers of left ventricular (LV) mass in subjects with newly diagnosed, untreated hypertension. METHODS: A total of 250 patients (40% women, 60% men; mean age 59.6 +/- 11 years) with essential hypertension who were attending the outpatient Hypertension Unit were studied. All patients underwent 24-h ABP and HR monitoring as well as echocardiography for assessment of left ventricular (LV) dimensions and function. RESULTS: A decreasing HR24 or increasing ABP parameters (ie, systolic, diastolic, mean BP, and pulse pressure) were associated with increasing LV mass (P < .001) and wall thickness (P < .01). In multivariate analysis, after adjusting for age, gender, body surface area, body mass index, hematocrit, glucose, cholesterol, smoking, and each of the measured ABP parameters separately, decreasing HR24 was independently related to increasing LV mass in addition to ABP and body size parameters (P < .001). The addition of HR24 in different multivariate models for prediction of LV mass significantly increased the adjusted model r2 (range of r2 change: 0.039 to 0.064, P for change <.05). Decreasing HR24 or HR during daytime (6 am to 10 pm) was associated with a higher likelihood of LV hypertrophy in addition to ABP parameters (adjusted odds ratio 0.92 (CI 0.87 to 0.98), per 1 beat/min greater HR24 P = .002 and 0.93 (CI: 0.87 to 0.98), per 1 beat/min greater HR in the daytime P = .017). CONCLUSION: The 24-h HR and BP during ABP are independent and additive markers of increased LV mass in untreated hypertensive individuals.  相似文献   

15.
BACKGROUND: Hypertensive left ventricular (LV) hypertrophy has been associated with diastolic dysfunction. However, the underlying physiological relationship between LV size and diastolic function remains to be clarified. The aim of this study was to evaluate the relationship between several measures of diastolic filling and LV mass in a population sample. METHODS: We used M-mode and Doppler echocardiography to compare left ventricular mass index (LVMI) and wall thickness with five measures of ventricular diastolic filling (ratio of the peak early mitral inflow velocity to the peak atrial mitral inflow velocity, deceleration time of early mitral inflow, isovolumetric relaxation time, ratio of the peak pulmonary venous systolic to diastolic flow and difference between the durations of the pulmonary venous and mitral inflow atrial waves) in 159 healthy volunteers. RESULTS: LVMI was significantly (P< 0.0001) greater in men (81.3 g/m2, interquartile range: 67-94) than women (59.7 g/m2, interquartile range: 49-74), but no gender differences were observed in diastolic filling. Higher age, blood pressure and heart rate showed significant correlation with diminished diastolic filling. However, no measure of diastolic filling correlated with LVMI or wall thickness in either univariate or multiple regression analyses that adjusted for relevant covariates. CONCLUSIONS: LVMI does not explain physiological differences in diastolic filling. The significant decline in diastolic filling with age reflects changes in the quality rather than the quantity of myocardial tissue.  相似文献   

16.
Aim To characterize the extent to which metabolic syndrome criteriapredict left ventricular (LV) structure and function. Methods and results Metabolic syndrome criteria were assessedin 607 adults with normal LV function. The cohort was groupedaccording to the number of criteria satisfied: (1) Absent (0criteria, n = 110); (2) Pre-Metabolic Syndrome (1–2 criteria,n = 311); and (3) Metabolic Syndrome (3 criteria, n = 186).Echocardiography was used to assess LV structure (LV mass) andsystolic (LVEF, Vs) and diastolic function, by pulse-wave Doppler(E/A ratio) and tissue Doppler imaging (Ve). LV volumes andLVEF were similar between groups. However, LV mass increasedsignificantly and progressively (LVM/Ht2.7, in g/m2.7: 34.9± 6.7, 41.0 ± 9.5, 46.3 ± 11.0, P <0.001); LV relaxation decreased progressively (Veglobal', incm/s: 13.5 ± 2.8, 12.1 ± 3.0, 10.5 ± 2.2,P < 0.001) from Absent to Pre-Metabolic Syndrome to MetabolicSyndrome groups, respectively. Multiple variable analyses showedthat diastolic blood pressure, waist circumference, and triglyceridelevels were independent predictors of Ve after adjustment forLV mass. Conclusion Patients with metabolic syndrome have LV diastolicdysfunction independent of LV mass. These functional abnormalitiesmay partially explain the increased cardiovascular morbidityand mortality associated with metabolic syndrome.  相似文献   

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To assess the relationship between insulin resistance and ambulatory blood pressure (BP) pattern, we determined glucose infusion rate (GIR) as a marker of insulin resistance using a glucose clamp method, and measured 24-h BPs in 25 normotensive, nonobese type 2 diabetic subjects. They were divided into two groups: 11 dippers and 14 nondippers. Clinical characteristics were similar in the two groups except for orthostatic fall in systolic BP. The median GIR level was significantly lower in nondippers than in dippers (P < 0.05). Spearman's rank correlation revealed that the GIRs were negatively correlated with the systolic, diastolic and mean BPs during nighttime (P < 0.05 or less), but not with daytime or whole day BPs. Moreover, based on a logistic regression analysis, the GIR as well as orthostatic fall in systolic BP discriminated independently between dippers and nondippers. Thus, our results suggest that insulin resistance is associated with decreased nocturnal BP fall in type 2 diabetic subjects.  相似文献   

20.
Blood pressure (BP) reduction to 140/90 mm Hg or lower using renin-angiotensin-system blockers reportedly provides the greatest left ventricular (LV) mass regression; β-blockers have less effect. This study examined whether combination antihypertensive therapy would provide greater benefit. With a double-blind, parallel-group design, the effects of 3 different combinations, carvedilol controlled-release (CR)/lisinopril, atenolol/lisinopril, and lisinopril, on left ventricular mass index (LVMI) were assessed by MRI after 12 months. Patients were treated to achieve guideline-recommended BP (<140 mm Hg/<90 mm Hg; diabetes: <130 mm Hg/<80 mm Hg). Sample size was calculated to achieve 90% power to detect a 5 g/m2 difference in mean change from baseline in LVMI between the carvedilol CR/lisinopril group and each of the other treatment groups. Of 287 patients randomized, more than 50% were titrated to maximum dosage; 73% reached targeted BP. At month 12 (last observation carried forward ≥ month 9) for 195 evaluable subjects, mean BP was similar in all groups (carvedilol CR/lisinopril: 128.8/77.9; atenolol/lisinopril: 128.7/76.5; lisinopril: 126.3/80.3 mm Hg). Compared with baseline, mean LVMI decreased to a similar extent in all groups (carvedilol CR/lisinopril: –6.3; atenolol/lisinopril: –6.7; lisinopril: –7.9 g/m2). Achievement of targeted BP control is more important than treatment regimen in achieving LV mass reduction.  相似文献   

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