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1.
BACKGROUND: Left ventricular hypertrophy (LVH) has been identified as a main target organ change resulting from hypertension, also being a long-term predictor of myocardial infarction, stroke and cardiovascular death. However, very few longitudinal studies exist following the development of LVH in the hypertensive process. METHODS: The present longitudinal study investigated a population based group of borderline hypertensive men (BHT, n = 66, diastolic blood pressure (BP) 85-94 mm Hg). M-mode echocardiography was performed at baseline and after 3 years, and anthropometrical data recorded. RESULTS: There was no increase in LVH indices over the 3-year period, while there was a statistically significant increase in aortic root dimension (P < 0.001), left atrial diameter in diastole (LADD, P < 0.001), left ventricular diameter in diastole (LVDD, P < 0.001) and peak systolic wall stress (PSWS, P < 0.01) and a significant decrease in left ventricular ejection time (LVET, P < 0.01). Baseline BP levels correlated to PSWS (P < 0.05) but not to LVH indices, whereas body mass index (BMI) correlated significantly to wall thickness (P < 0.05) and LV mass (P < 0.05). CONCLUSIONS: LVH indices did not increase over a 3-year period. However, there was a significant increase in aortic root dimension, LADD, LVDD and PSWS, and a significantly shortened LVET, suggesting that these changes precede any increase in LVH. Finally, BMI showed stronger correlation to LVH indices than did BP levels.  相似文献   

2.
The aim of the study was to assess whether the hypotensive activity of amlodipine is associated with regression of left ventricular hypertrophy and improvement of impaired LV or right ventricular (RV) diastolic function or increasing of tolerance of physical activity in hypertensive patients. Assessment of left ventricular structure, systolic and diastolic function as well as RV diastolic dimension and diastolic function were performed in 24 patients with mild-to-moderate hypertension before administration of amlodipine and 3, 6 and 9 months of the treatment. In order to assess the tolerance of physical activity, incremental treadmill exercise testing was performed at baseline and after 6 and 9 months of the therapy with amlodipine. RESULTS: During 9 months of the therapy with amlodipine no significant change in indexes of LV mass or in LVM was observed. Similarly amlodipine did not influence the parameters of LV or RV diastolic function in studied patients. However, amlodipine treatment resulted in significant increase in total exercise time (p < 0.05), total workload (p < 0.01) measured in METs and decrease in diastolic blood pressure during exercise test. CONCLUSION: The nine months of the therapy with amlodipine resulted in significant improvement in exercise tolerance. Total exercise duration and total workload measured in METs significantly increased. During this time of the therapy no significant changes in LV structure or LV and RV diastolic function were observed. One can make an assumption that amlodipine inhibits progression of structural and functional derangement in hypertensive patients.  相似文献   

3.
BACKGROUND: The prevalence of left ventricular hypertrophy (LVH) is higher in elderly patients with hypertension than in normotensive patients. The factors relationed herewith are not well known. The first purpose was to analyse the relationship between the levels of blood pressure (BP) recorded by ambulatory blood pressure monitoring (ABPM) and the left ventricular mass index (LVMI) in a group of untreated patients older than 55 years with essential hypertension. Our second purpose was to observe the relationship between the concentration of several circulating hormones and the left ventricular mass index. SUBJECTS AND METHODS: The study included 31 untreated patients with mild to moderate essential hypertension and 37 healthy normotensives. Both groups were of similar age, sex and body mass index. We determined for both groups the casual arterial pressure (CAP), ambulatory BP monitoring (ABPM) throughout 24 h, daytime (07.00-23.00 h), nighttime (23.00-07.00 h), left ventricular mass index (LVMI) (following Devereux's formula) and circulating levels of endothelin-1, aldosterone, renine, free adrenaline and noradrenaline. RESULTS: The ILVM in hypertensive patients was 139.6 +/- 35.9 g/m2 and in 124.0 +/- 31.8 g/m2 in normotensive (p < 0.05). The percentage of patients with LVH was 63 and 43%, respectively (p < 0.05). The LVMI in hypertensive patients was correlated with the diastolic CAP (97 +/- 7 mmHg) (r = 0.41; p < 0.05), unlike with the systolic CAP (164 +/- 18 mmHg). The ILVM in normotense patients was not associated neither with the systolic CAP (126 +/- 10 mmHg) nor with the diastolic (79 +/- 6 mmHg). In hypertensive patients we found a slight association between the LVMI and the systolic ABPM (130 +/- 14 mmHg) during nighttime (r = 0.41; p < 0.05). The rest of average ambulatory BP and the hormonal values at study did not show a correlation with the LVMI in both groups. CONCLUSIONS: A slight correlation exists between BP (casual and determined with ambulatory blood pressure monitoring throughout 24 hours) and the left ventricular mass index in mild to moderate untrated hypertensive patients older than 55 years. We did not observe correlations between the circulating levels of endothelin-1, renin, aldosterone, free adrenaline and noradrenaline and the left ventricular mass. The average ventricular mass and the number of subjects with ventricular hypertrophy was significantly increased in hypertensives than in normotensives.  相似文献   

4.
PURPOSE: To evaluate the role of casual and exercise blood pressure as well as the importance of clinical factors on the presence and degree of left ventricular hypertrophy in hypertension. METHODS: Fifteen normotensives (control group) and 30 hypertensives, 14 of them with and 16 without left ventricular hypertrophy (groups with LVH and without LVH, respectively) were studied. LVH diagnosis was established when mass index was higher than 2 standard-deviations of the mean values calculated for each sex in control group. Resting, casual determined, and bicycle exercise systolic and diastolic blood pressures along with age, body surface area, sex and race distribution were compared between groups. In addiction, their relation with mass index as independent variables were also tested. RESULTS: Hypertensives in group with LVH had higher diastolic septal, posterior wall, and relative wall thicknesses. No significant statistical difference was observed neither in sex and race distribution, nor in age and body surface area between groups. Otherwise, there were significant differences in both resting and exercise blood pressure. In the entire population studied, left ventricular mass index significantly correlated with age (r=0,33, p=0,03) as well as with both casual (systolic - r=0,72, p=0,0001; diastolic - r=0,69, p=0,0001) and exercise (systolic - r=0,62, p=0,0001; diastolic - r=0,66, p=0,0001) blood pressures. However, linear regression analysis demonstrated that only resting systolic (p=0,0001) and exercise diastolic (p=0,0303) blood pressures were significant and independent determinants of mass index. CONCLUSION: Resting and exercising blood pressures are the main determinants of left ventricular hypertrophy in hypertension.  相似文献   

5.
Increased sympathetic nervous activity has been proposed as one of the causes of left ventricular hypertrophy (LVH) associated with hypertension. However, the precise relationship is not fully understood. METHODS: To elucidate the relationship between myocardial sympathetic nervous activity and LVH in patients with essential hypertension EHT), we performed 123I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy in 49 patients with EHT and 17 normotensive control subjects. Sympathetic innervation of the left ventricle was evaluated using SPECT, and the whole heart uptake of the tracer was quantitatively assessed as the heart-to-mediastinum uptake ratio on both the early (15-min) and delayed (5-hr) images. Myocardial washout rate (MWR) of the tracer from 15 min to 5 hr after the isotope administration was also calculated. The left ventricular mass index (LVMI) was determined echocardiographically. RESULTS: In 49 hypertensive patients, there was a negative correlation between LVMI and heart-to-mediastinum uptake ratio on both the early and delayed images (r=-0.55, p < 0.0001; r=-0.63, p < 0.0001, respectively). In addition, there was a positive correlation between the LVMI and MWR of 123I-MIBG in these hypertensive patients (r=0.59, p < 0.0001). As for the regional uptake of the tracer, there was no significant difference between control subjects and hypertensive patients without cardiac hypertrophy, but a significant decrease of the uptake in the inferior and lateral regions was observed in hypertensive patients with cardiac hypertrophy. CONCLUSION: Patients with EHT had decreased accumulation and increased MWR of 123I-MIBG in proportion to the degree of LVH. Hypertensive patients with cardiac hypertrophy had impaired sympathetic innervation in the inferior and lateral regions of the left ventricle.  相似文献   

6.
We examined the relationship between left ventricular hypertrophy (LVH) and renal and retinal damage in 174 untreated patients with essential hypertension. As an index of renal and retinal damage, we examined proteinuria and retinal vascular change. LVH was diagnosed according to left ventricular mass obtained from echocardiography. Of the hypertensive patients, 111 patients (64%) had LVH. The incidences of proteinuria and advanced retinal vascular change were higher in patients with LVH than in those without LVH. In a multiple regression model, there was a significant positive correlation between left ventricular mass and proteinuria, as well as diastolic blood pressure, sex, age and body mass index. In conclusion, proteinuria is related to elevated left ventricular mass in patients with essential hypertension.  相似文献   

7.
Left ventricular hypertrophy (LVH) is an independent cardiovascular risk factor. It has not been established, however, whether left ventricular geometry is an independent predictor of extracardiac target organ damage in essential hypertension. Study groups were classified according to relative wall thickness: 27 patients with concentric LVH and 50 patients with eccentric LVH. Age and left ventricular mass indexes of two groups were matched. As indexes of extracardiac target organ damage, retinal funduscopic grade, and serum creatinine level were measured. The severity of hypertensive retinopathy and the renal involvement were more severe in patients with concentric LVH than in patients with eccentric LVH. Extracardiac target organ damage was consistently higher in patients with concentric LVH than in those with eccentric LVH. Systemic hemodynamics paralleled ventricular geometric patterns, with higher peripheral resistance and lower aortic compliance in patients with concentric LVH, whereas end-diastolic volumes and stroke volumes were higher in patients with eccentric LVH than in patients with concentric LVH. In addition, total peripheral resistance was related to retinal fundoscopic grade (r = 0.41, P < .01), and serum creatinine level (r = 0.28, P < .05). Even in the presence of an identical degree of LVH, echocardiographically determined left ventricular geometry may provide a further independent stratification of extracardiac target organ damage in essential hypertension.  相似文献   

8.
Reversal of left ventricular hypertrophy has been shown to improve left ventricular diastolic function in elderly patients with hypertension, but little is known about whether this affects physical performance. Left ventricular mass, cardiac function at rest and during submaximal exercise, and physical performance were assessed in 38 elderly patients with hypertension with left ventricular hypertrophy and normal systolic function before and after 8 and 14 months of therapy with amlodipine or hydrochlorothiazide or both. Blood pressure control was achieved with amlodipine in 18 patients, with hydrochlorothiazide in seven, and with the combination of these drugs in 13. Left ventricular mass index was similarly reduced from approximately 150 to approximately 100 g/m2 at 14 months' in each treatment group. Systolic function was maintained with the three treatment regimens, whereas similar decreases in time to peak filling rate and increases in first-third filling fraction occurred both at rest and during submaximal exercise after 8 months and further after 14 months of therapy. Exercise capacity did not significantly change in the group as a whole, but individual changes in peak oxygen uptake at the end of treatment correlated significantly with the decrease in time to peak filling rate during submaximal exercise (r = -0.49; p < 0.01). It is concluded that long-term blood pressure control with amlodipine or hydrochlorothiazide or both is associated with significant reductions in left ventricular mass and improved diastolic function in elderly patients with hypertension with left ventricular hypertrophy. Despite this reduction in left ventricular mass, left ventricular systolic function and physical performance are well preserved during submaximal exercise.  相似文献   

9.
OBJECTIVES: To assess the relation between white coat hypertension and alterations of left ventricular structure and function. DESIGN: Cross sectional survey. SETTING: Augsburg, Germany. SUBJECTS: 1677 subjects, aged 25 to 74 years, who participated in an echocardiographic substudy of the monitoring of trends and determinants in cardiovascular disease Augsburg study during 1994-5. OUTCOME MEASURES: Blood pressure measurements and M mode, two dimensional, and Doppler echocardiography. After at least 30 minutes' rest blood pressure was measured three times by a technician, and once by a physician after echocardiography. Subjects were classified as normotensive (technician <140/90 mm Hg, physician <160/95 mm Hg; n=849), white coat hypertensive (technician <140/90 mm Hg, physician >=160/95 mm Hg; n=160), mildly hypertensive (technician >=140/90 mm Hg, physician <160/95 mm Hg; n=129), and sustained hypertensive (taking antihypertensive drugs or blood pressure measured by a technician >=140/90 mm Hg, and physician >=160/95 mm Hg; n=538). RESULTS: White coat hypertension was more common in men than women (10.9% versus 8.2% respectively) and positively related to age and body mass index. After adjustment for these variables, white coat hypertension was associated with an increase in left ventricular mass and an increased prevalence of left ventricular hypertrophy (odds ratio 1.9, 95% confidence interval 1.2 to 3.2; P=0.009) compared with normotensive patients. The increase in left ventricular mass was secondary to significantly increased septal and posterior wall thicknesses whereas end diastolic diameters were similar in both groups with white coat hypertension or normotension. Additionally, the systolic white coat effect (difference between blood pressures recorded by a technician and physician) was associated with increased left ventricular mass and increased prevalence of left ventricular hypertrophy (P<0.05 each). Values for systolic left ventricular function (M mode fractional shortening) were above normal in subjects with white coat hypertension whereas diastolic filling and left atrial size were similar to those in normotension. CONCLUSION: About 10% of the general population show exaggerated inotropic and blood pressure responses when mildly stressed. This is associated with an increased risk of left ventricular hypertrophy.  相似文献   

10.
It has been suggested that the deletion polymorphism of the angiotensin-converting enzyme (ACE) genotype may be important in the development of left ventricular hypertrophy (LVH). In order to test this hypothesis we investigated the interaction between blood pressure (BP), LVH and ACE genotype in 86 previously untreated hypertensive patients. Each underwent two-dimensional and Doppler echocardiography and ACE genotyping. There were no significant differences in BP, the parameters of left ventricular structure (including left ventricular mass index) or diastolic function between the three genotype groups. Additionally, there were no significant differences in the relationship between systolic BP and left ventricular mass index among the three genotype groups (II genotype, r = 0.46, P = 0.02; ID genotype, r = 0.42, P = 0.01; DD genotype, r = 0.34, P = 0.10; F = 0.38). In contrast to some previous studies, we have found in this group of previously untreated hypertensive subjects no evidence to suggest that the deletion polymorphism of the ACE genotype is important in the development of LVH.  相似文献   

11.
OBJECTIVE: To investigate in patients with arterial hypertension (HT) the extent of left ventricular (LV) hypertrophy and diastolic function in relation to atrial arrhythmias. PATIENTS AND METHODS: In 112 hypertensive patients (40 women, 72 men; mean age 50 +/- 6.6 years) with a mean systolic blood pressure for the cohort of 170 +/- 5 mmHg, their first invasive coronary angiography was performed between July 1995 and October 1997 because of angina pectoris and/or an abnormal stress electrocardiogram. After excluding coronary heart disease LV dimensions and diastolic function were measured by echocardiography; in 59 of the 112 patients LV hypertrophy was demonstrated. In addition, long-term blood pressure monitoring, exercise and long-term electrocardiography, late-potential analysis and measurement of heart rate variability were undertaken. The control group consisted of 51 patients without arterial hypertension after exclusion of coronary heart disease. RESULTS: Even in the hypertensive patients without LV hypertrophy diastolic LV function and ergometric exercise capacity were reduced. The risk of LV arrhythmias was significantly higher in patients with LV hypertrophy than those without and in the control group, as measured by the complexity of atrial arrhythmias (P < 0.001), the incidence of abnormal late potentials (P < 0.001) and reduction in heart rate variability (29.3 +/- 5.3 ms vs 47.8 +/- 12.1 ms vs 60.7 +/- 6.6 ms; P < 0.001). There were similar results regarding severe complex atrial arrhythmias (38.5 vs 15.0 vs 0%; P < 0.001). The incidence of atrial arrhythmias correlated with the LV diameter (r = 0.68, P < 0.001), LV morphological dimensions and diastolic function (isovolumetric relaxation time r = 0.44, P < 0.001) and the ratio of early to late diastolic inflow (r = 0.46; P < 0.001). CONCLUSIONS: Hypertensive patients have a higher risk of atrial and ventricular arrhythmias, depending on the degree of LV hypertrophy. But atrial arrhythmias, in contrary to ventricular arrhythmias, are also closely related to abnormalities in LV diastolic function.  相似文献   

12.
To evaluate left ventricular diastolic filling properties in elderly hypertensive case with left ventricular hypertrophy (LVH), we investigated the influence of postural change from a supine to sitting position on transmitral flow velocity profile as assessed by pulsed Doppler echocardiography in 12 normotensives (N group) and 24 hypertensives, aged 65 to 80 years. Hypertensive subjects were divided into two groups on the basis of left ventricular mass index (LVMI): 12 hypertensives without LVH (H1 group; LVMI < 130 g/m2); 12 hypertensives with LVH (H2 group; LVMI > 130 g/m2). Peak early filling velocity (E), peak atrial filling velocity (A) and the E/A ratio were similar in the three groups in the supine position. The postural change decreased E and A in N and H1 groups. On the other hand, the change decreased E, but not A in the H2 group. The E/A ratio was decreased in the H2 group compared with both the N and H1 group in the sitting position. As a result, the sitting position increased atrial contribution to diastolic filling in the H2 group. These observations indicate that a reduction in preload changes the transmitral flow velocity profile in elderly hypertensives with left ventricular hypertrophy. The Doppler alterations may be related to impaired left ventricular diastolic function.  相似文献   

13.
The influence of glucose intolerance, the preclinical stage of diabetes mellitus, on the progression of left ventricular hypertrophy and left ventricular dysfunction in essential hypertension, was assessed with two-dimensional M-mode echocardiography in age- and sex-matched essential hypertensive patients with (n = 28) or without (n = 44) glucose intolerance, and normotensive control subjects (n = 29). Left ventricular mass index in hypertensive patients with glucose intolerance was significantly higher than that in hypertensive patients without glucose intolerance (mean +/- SD, 115.6 +/- 28.2 v 102.1 +/- 22.1 g/m2; P < .05). Left ventricular diastolic function as reflected by peak lengthening rate was reduced in glucose-intolerant hypertensive patients than in hypertensive patients without glucose intolerance (2.68 +/- 0.71 v 3.16 +/- 0.82/sec; P < .05). End-systolic wall stress/left ventricular end-systolic volume index, an index of left ventricular contractility, was reduced more in glucose-intolerant hypertensive patients than in hypertensive patients without glucose intolerance (2.75 +/- 0.55 v 3.13 +/- 0.55 10(3) dyn.m2/cm2.mL-1; P < .01). These findings suggest that glucose intolerance accelerates progression of left ventricular hypertrophy and deteriorates left ventricular diastolic function and contractility in essential hypertension.  相似文献   

14.
AIM: To examine the incidence and natural history of left ventricular hypertrophy (LVH) associated with the shorter 2-3 week course of dexamethasone, now more usual, for chronic lung disease. METHOD: Thirty one infants, gestational age 23-34 (median 26) weeks, birthweight 500-2054 (median 815)g, received dexamethasone, starting at 0.4-0.6 mg/kg/day, at a median of 11 days of age (range 2-34), weaning over a period of 2-3 weeks. Eighteen preterm neonates were studied as controls over a similar time period. Serial echocardiographic measurements of end diastolic interventricular septum (IVSd) and left ventricular posterior wall (LVPWd) thicknesses were taken before, and up to 48 days after, starting dexamethasone. Maximum Doppler blood flow velocities from the left ventricular outflow tract (LVOT) were measured. RESULTS: Left ventricular hypertrophy (LVH) occurred in 29 babies (94%). Median hypertrophy of the IVSd in those receiving dexamethasone was 67% and LVPWd 56% of baseline measurements, significantly greater than control infants (p < 0.001). LVH appeared by a median of three days, peaking by a median of 10 days. All resolved by a median of 27 days. LVOT obstruction was not seen. There was no significant correlation with birthweight, gestation, blood pressure, or glucose tolerance. CONCLUSIONS: LVH developed in almost all preterm neonates receiving a 2-3 week course of dexamethasone, but was of little clinical importance and always resolved. Echocardiography is probably not required routinely in infants receiving such short course dexamethasone for chronic lung disease.  相似文献   

15.
In the past few years in Western countries, there has been an increasing proportion of elderly patients beginning renal replacement therapy. Left ventricular hypertrophy (LVH) is associated with an increased mortality rate due to cardiovascular disease, the main cause of death in patients on chronic hemodialysis. In this study, we evaluated 67 chronic hemodialysis patients older than 65 years (33 women and 34 men; mean age, 72.6 years; mean time on chronic hemodialysis, 51.3 months). Several biological and laboratory data were analyzed. The left ventricular mass was calculated using the Penn convention criteria. LVH was observed in 49 patients (73%). These 49 patients were divided into two groups (group 1, concentric hypertrophy, n = 22; and group 2, eccentric hypertrophy, n = 27) and compared with a control group (patients without LVH, n = 18). Group 1 (P = 0.06) and group 2 (P = 0.055) showed higher systolic blood pressures and group 2 showed a lower hematocrit (P = 0.024). The echocardiographic parameters were expectedly different: group 1 had higher posterior left ventricular wall thickness (P = 0.0001), interventricular septum thickness (P = 0.0001), and left ventricular wall relative thickness (P = 0.002), and group 2 had higher left ventricular end-diastolic diameter (P = 0.0001), interventricular septum thickness (P = 0.01), and posterior left ventricular wall thickness (P = 0.023). Using the left ventricular mass index as the dependent variable and the evaluated biological and laboratory data as the independent variables, we found in a stepwise multiple regression model that only systolic blood pressure (t = 3.430; P = 0.0011), age (t = 2.059; P = 0.044), interdialytic weight gain (t = 2.236; P = 0.029), and hematocrit (t = -1.961; P = 0.054) independently influenced the left ventricular mass index (R2 = 0.313; P = 0.0001). Further studies are needed to determine whether reduction of the left ventricular mass index, through control of blood pressure and correction of anemia, will decrease the cardiovascular events in this particular population.  相似文献   

16.
BACKGROUND: Many factors influence diastolic function indexes obtained by monitoring left ventricular filling. Recent reports suggest that the study of myocardial wall velocity with Doppler tissue imaging (DTI) can give diastolic function parameters that are less affected by the same factors. An altered diastolic function has been demonstrated with invasive methods in patients with left ventricular hypertrophy (LVH). The aims of this study were 1) to compare a group of healthy subjects with a group of patients with LVH and presumably affected by diastolic dysfunction, to try to demonstrate if DTI could give new indexes to discriminate between the two groups; 2) to compare the indexes obtained with DTI against the ones given by Doppler study of left ventricular filling in the two populations. MATERIALS AND METHODS: Forty-two patients with LVH were compared to forty normal subjects. We studied the posterior wall velocity with pulsed DTI from parasternal view, measuring the early diastolic velocity (E'), the late diastolic velocity (A') and the E'/A' ratio. In addition, we estimated the usual ventricular filling parameters and the time interval between R wave of ECG and the peaks of E' and E waves. RESULTS: At left ventricular filling, patients with LVH showed an increase in A-wave peak velocity (mean 75.3 cm/s versus 66.4 cm/s; p < 0.05) and prolonged deceleration time (mean 216 ms versus 181 ms; p < 0.05), as compared to normal reference subjects. E-wave peak velocity and E/A ratio did not differ between the two groups. At DTI, patients with LVH had decreased early diastolic velocity (E') (mean 9 cm/s versus 12 cm/s; p < 0.05) and E'/A' ratio (mean 1.53 versus 1.91; p < 0.05) as compared to the control group. We observed an inverse correlation between E' wave and age in normal subjects. There was no correlation between the early diastolic myocardial velocity (E') and early inflow velocity (E) in both groups. A correlation was found between A and A' waves in normal subjects, but not in hypertrophic ones. The E'-wave peak always preceded the E-wave peak in all the subjects. CONCLUSION: Diastolic function indexes achieved by DTI can offer additional information that is independent of the data derived from left ventricular filling.  相似文献   

17.
Hemodynamic and non-hemodynamic factors contribute to the development of left ventricular hypertrophy (LVH). The presence of LVH is an important independent risk factor for total mortality and for cardiovascular morbidity and mortality. Direct cardiac effects of LVH include an increased risk of developing of congestive heart failure, an increased risk of arrhythmic events, and a reduced coronary flow reserve, promoting myocardial ischemic episodes. In addition, hypertension may promote the development of coronary artery atherosclerosis. The prognostic implications of LVH underscore the importance of diagnostic procedures. The electrocardiogram has a high specificity to identify patients with LVH but the sensitivity is fairly low. Echocardiography provides higher sensitivity and also gives important information, such as the pattern of left ventricular geometry, which is of prognostic importance, and the presence of diastolic dysfunction, which is an early abnormality in the evolution of hypertensive LVH. Reversal of LVH appears to improve prognosis. Reduction of blood pressure is one important component in the regression of LVH. Important quantitative differences exist between drug classes in the reversal of cardiac hypertrophy despite similar antihypertensive effects, suggesting other factors to be of importance in the regression of left ventricular mass. LVH is reduced more by angiotensin-converting enzyme inhibitors than by other antihypertensive drug classes, suggesting an effect on structural myocardial changes beyond that provided by the reduction of blood pressure. Recent data suggest that angiotensin II receptor antagonists (AIIRAs) have quantitatively similar effects on left ventricular mass as do angiotensin-converting enzyme inhibitors. A comparative trial of the AIIRA irbesartan and the beta-blocker atenolol demonstrated that despite similar reductions in blood pressure, the reductions attained in left ventricular mass with irbesartan were progressive and numerically greater than those attained with atenolol. Taken together, these findings provide circumstantial evidence for an important role of angiotensin II acting on angiotensin type 1 (AT1) receptors in the development or maintenance of cardiac hypertrophy. Confirmation of the favorable effects of angiotensin-converting enzyme inhibitors and AIIRAs on left ventricular mass in larger trials, including those assessing cardiovascular morbidity and mortality, will be of major importance in the future treatment of hypertension.  相似文献   

18.
Transthoracic Doppler color flow and spectral velocity patterns of normal coronary arteries in children have not been well studied. We designed this study to evaluate coronary artery flow velocity characteristics in normal and hypertrophied hearts. Sixty-eight children with optimal two-dimensional echocardiographic images of the left coronary artery (LCA) and right coronary artery (RCA) were prospectively studied. The heart was normal in 45 children, and 23 had left and/or right ventricular hypertrophy assessed by echocardiography (mean age 5.8 versus 5.2 years, p = NS). Color flow signals were detected in the LCA in 63(92%) of the 68 children studied, and pulsed Doppler spectral waveforms were recorded in 47 (69%). The latter were recorded in 26 (58%) of 45 normal children and in 21 (91%) of 23 children with left ventricular hypertrophy. Diastolic RCA flow signals were detected mostly in those with right ventricular hypertrophy (10 of 10). Higher levels of LCA maximum diastolic velocity (42 +/- 23 versus 24 +/- 6 cm/sec, p = 0.0004), increased diastolic flow (16 +/- 15 versus 6 +/- 4 ml/min, p = 0.01), and delayed time to peak diastolic velocity expressed as a percentage of diastolic spectral duration (38% +/- 14% versus 20% +/- 8%, p = 0.0001) were observed in children with left ventricular hypertrophy than in those in normal children. A strong correlation was present between Doppler-derived LCA flow and left ventricular mass/m2 (r = 0.7, p = 0.001). In normal hearts, LCA spectral velocity pattern did not change with increasing age, but the time velocity integral became progressively larger, resulting in a strong correlation with weight (p < 0.001, r = 0.78). This study demonstrates (1) LCA flow signals can be detected and quantitated in the majority of children with and those without left ventricular hypertrophy. (2) Left ventricular hypertrophy is associated with increased LCA flow, higher diastolic velocity, and delayed peak diastolic velocity. (3) RCA flow signals are mostly detected when there is right ventricular hypertrophy. Studies on larger groups of patients are needed to further confirm our observations and to enhance understanding of coronary artery flow reserve.  相似文献   

19.
OBJECTIVE: Hypertensive left ventricular hypertrophy (LVH) is associated with increased risk of arrhythmias and mortality. However, no clinical study demonstrated a significant relation between ventricular arrhythmias and mortality in systemic hypertension. DESIGN AND METHODS: To evaluate the prognostic value of arrhythmogenic markers in systemic hypertension, we included between 1987 and 1993. 214 hypertensive patients, 59.1 +/- 12.8 years old, without symptomatic coronary disease, myocardial infarction, systolic dysfunction, electrolyte disturbances or antiarrhythmic therapy. At inclusion, an ECG, a 24 h Holter ECG (204 patients) with Lown classification of ventricular arrhythmias, an echocardiography (reliable in 187 patients) with left ventricular mass index and ejection fraction calculation, a SAECG (125 patients, enrolled after 1988) with ventricular late potentials (LP) were recorded. QT interval dispersion (QTd) was calculated on 12 leads standard ECG and LVH was appreciated. RESULTS: At baseline echocardiographic LVH was recorded in 63 patients (33.7%) with normal ejection fraction (75 +/- 7.4%). Non-sustained ventricular tachycardia (Lown IVb) was found in 33 pts (16.2%) and LP in 27 patients (21.6%). After a mean follow up of 42.4 +/- 26.8 months, all-cause mortality was 11.2% (24 patients); 17 patients died of cardiac causes (7.9%); of these 9 patients (4.2%) died suddenly. In univariate analysis, age, strain pattern of LVH, advanced Lown classes and abnormal QT dispersion (> 80 ms) were significantly related to global, cardiac and sudden death (p < or = 0.01). Left ventricular mass index was closely related to cardiac mortality (p = 0.002). LP failed to predict mortality. In multivariate analysis, only Lown class IVb was an independent predictor of global and cardiac mortality, increasing the risk of global death 2.6 fold [1.2-6.0] (CI 95%) and the risk of cardiac death 3.5 fold [1.2-9.7] (CI 95%). CONCLUSIONS: In hypertensive patients the presence of non-sustained ventricular tachycardia on 24 h Holter has a prognostic value.  相似文献   

20.
Left ventricular hypertrophy (LVH) is associated with decreased contractile response to inotropic stimulation in animal models, but this has not been documented in humans. To determine whether LVH is associated with decreased myocardial contractile reserve, we measured left ventricular mass, heart rate-corrected velocity of circumferential fiber shortening (Vcfc), end-systolic stress, and LV ejection fraction (LVEF) in patients with LVH and increased end-systolic stress (n = 6) and in patients without LVH (n = 7) who had a normal response to dobutamine stress echocardiography (increased LVEF and no wall motion abnormalities). The afterload-dependent indexes of left ventricular systolic performance were normal at baseline and showed significant increases at peak dobutamine dose (LVH group: Vcfc 0.91 +/- 0.11 to 1.76 +/- 0.59, p = 0.006; LVEF 49 +/- 5 to 65 +/- 6, p = 0.001; group without LVH: Vcfc 1.16 +/- 0.24 to 1.99 +/- 0.36, p = 0.001; LVEF 61 +/- 6 to 68 +/- 6, p = 0.05). The Vcfc/ end-systolic stress relation, a load-independent index of myocardial contractility, rose in a dose-dependent fashion in both groups, but the increment was significantly less for patients with LVH (p < 0.02), suggesting a blunted myocardial contractile reserve to inotropic stimulation. The change in heart rate-corrected velocity of circumferential fiber shortening per unit of change in end-systolic stress in each patient at each dobutamine dose showed a linear and inverse relationship. The increment in heart rate-corrected velocity of circumferential fiber shortening for a given reduction in end-systolic stress was larger in patients without LVH than in patients with LVH (p = 0.01). These results suggest that in patients with LVH and increased end-systolic stress, ventricular performance is maintained at the expense of limited myocardial contractile reserve, and that inotropic stimulation unmasks this abnormality, despite a normal response in LVEF and velocity of circumferential fiber shortening. This approach may identify patients with LVH at risk of developing systolic dysfunction and heart failure.  相似文献   

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