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1.
AIM: Left ventricular concentric remodelling defines a modified left ventricular geometry in the presence of a normal left ventricular mass; it is an early and frequent adaptation in arterial hypertension. The present study was designed to evaluate the extent of carotid structural changes in essential hypertensives with left ventricular remodelling. PATIENTS AND METHODS: Two groups of hypertensive patients, who had never previously received anti-hypertensive treatment, 14 with left ventricular concentric remodelling (group I, relative wall thickness 0.48 +/- 0.02) and 48 with normal left ventricular geometry (group II, relative wall thickness 0.37 +/- 0.04) underwent clinical and laboratory examination, echocardiography, carotid artery ultrasonography and 24 h ambulatory blood pressure monitoring (ABPM). The left ventricular dimensions and mass were obtained according to the Penn convention. The intima-media thickness (IMT) of the posterior wall of both common carotid arteries was measured 5, 10 and 20 mm caudally to the bulb and the average value was used for analysis. RESULTS: In both groups age (group I 44 +/- 9 years; group II 40 +/- 9 years), body surface area (group I 1.85 +/- 0.2 m2; group II 1.80 +/- 0.2 m2), duration of hypertension (group I 4.4 +/- 4; group II 3.8 +/- 3.9 years), metabolic parameters and smoking habits were similar. Both clinic and 24 h ABPM values were higher in group I (clinic 157 +/- 12/102 +/- 5; 24 h ABPM 145 +/- 10/95 +/- 7 mmHg) than they were in group II (clinic 146 +/- 11/97 +/- 5; 24 h ABPM = 134 +/- 10/87 +/- 8 mmHg, P < 0.01). The left ventricular mass index (LVMI) and IMT were found to be slightly but significantly greater in group I than they were in group II (LVMI 106 +/- 7 versus 98 +/- 12 g/m2, P < 0.05; IMT 0.68 +/- 0.13 versus 0.61 +/- 0.10 mm, P < 0.05). A significant correlation was found between LVMI and common carotid IMT in the whole group of hypertensive patients (r = 0.43, P < 0.01). CONCLUSIONS: Our results indicate that left ventricular concentric remodelling does not represent the only early cardiovascular change in arterial hypertension but rather is associated often with carotid intima-media thickening.  相似文献   

2.
Black hypertensive persons have been observed to have a greater degree of left ventricular hypertrophy than white hypertensives. However, previous studies have matched groups for blood pressure (BP) measured in the clinic, and it has been demonstrated that black hypertensives have an attenuated nocturnal BP dip. Clinic BPs may thus underestimate mean 24-hour BP in this group. To investigate whether the differences in left ventricular hypertrophy can be accounted for by the greater mean 24-hour BP in black hypertensives, 92 previously untreated hypertensives were studied with 24-hour ambulatory BP monitoring and echocardiography. The 46 black hypertensives (24 men and 22 women) were matched with the 46 white hypertensives for age, gender, and mean 24-hour BP. Despite similar mean 24-hour BPs (blacks, 142/93 mm Hg; whites, 145/92 mm Hg; P=.53/.66), the black group had a smaller mean nocturnal dip than the white group (blacks, 8/8 mm Hg; whites, 16/13 mm Hg; P<.01). In addition, mean left ventricular mass index (LVMI) was greater (blacks, 130 g/m2; whites, 107 g/m2; P<.001). Mean 24-hour systolic BP was significantly related to LVMI in both groups (blacks, r=.45, P<.01; whites, r=.56, P<.01). However, systolic BP dip correlated inversely with LVMI only in the black group (blacks, r=-.30, P<.04; whites, r=.05, P=.76). In a multiple regression model, LVMI was independently related to both mean daytime BP and mean nocturnal BP dip in black subjects but only to mean daytime BP in white subjects. In conclusion, the increased left ventricular hypertrophy observed in black hypertensives compared with white hypertensives is not accounted for by differences in mean 24-hour BP. However, LVMI in black hypertensives appears to be more dependent on nocturnal BP than that in white hypertensives; this, coupled with the attenuated BP dip in black hypertensives, suggests that the BP profile rather than 24-hour BP may be important in determining the differences in left ventricular hypertrophy.  相似文献   

3.
To evaluate the behavior of cardiac arrhythmias (CA) and transient episodes of myocardial ischemia (TEMI), in relation to the circadian pattern of blood pressure in patients suffering from arterial hypertension, with or without echocardiographically ascertained left ventricular hypertrophy (LVH), we studied 128 patients, 87 men (M) and 41 women (F), aging from 21 to 76 years, subdivided into two groups: Group I, including 66 patients with LVH (45 M and 21 F; mean age of 53.7 +/- 9.1 years; Group II, including 62 patients without LVH (42 M and 20 F; mean age of 49.7 +/- 9.5 years). Office blood pressure (OBP) as well as nighttime ambulatory blood pressure (ABP) were higher in patients with LVH (P < .05 and P < .01). CA were present in a higher number of patients of Group I (P < .001): premature supraventricular beats (PSVB) 22.7 v 4.8%, supraventricular couplets (SVC) 36.4 v 16.1%, supraventricular tachycardia runs (SVT runs) 27.3 v 12.9%, ventricular ectopic beats (VEB) 25.6 v 8.0%, ventricular couplets (VC) 30.3 v 12.9%, ventricular tachycardia runs (VT runs) 12.1 v 3.2%. The absolute number of ectopic beats was also significantly higher in patients of Group I. Ventricular arrhythmias were significantly related to ASBP (r = 0.83, P < .01), to ADBP (r = 0.74, P < .01) and to heart rate (r = 0.87, P < .01) in patients of Group I. TEMI were more frequent in patients of Group I (73 v 41 episodes, 39.39% v 25.8% of patients, P < .01) and were related to ABP peaks. In fact, in both groups of patients all TEMI without heart rate increase and most TEMI with heart rate increase were registered between 6:00 and midnight, hours in which ABP values were higher. We conclude that hypertensives with LVH, but without clinical history of coronary heart disease, have a higher prevalence of ventricular arrhythmias and of transient episodes of myocardial ischemia in relation to the circadian pattern of ABP.  相似文献   

4.
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   

5.
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   

6.
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   

7.
AIMS: This study was designed to assess the changes in left ventricular mass (LVM) in hypertensive patients with left ventricular hypertrophy under drug therapy with once-daily slow-release diltiazem. Magnetic resonance imaging (MRI) was used for this purpose because of its higher reproducibility than M-mode or two-dimensional echocardiography. METHODS: Patients suffering from essential hypertension were included if their baseline LVM index (LVMI) was > or = 105 g/m2 in male or > or = 85 g/m2 in female patients, ie, equal or higher to the median values observed in hypertensive patients in our institution. MRI consisted in a true short-axis, electrocardiogram (ECG) gated spin-echo slice acquisition at baseline, after 3 and 6 months of therapy (M0, M3, and M6). Data were stored on magnetic tapes and read subsequently under blind conditions and the control of an external auditor. RESULTS: Thirty-five patients were included. Of these, 14 patients (40%) were not previously treated. Inter- and intra-observer variability for LVMI measurement were 5.6 +/- 4.3% and 2.1 +/- 3.0%, respectively. Mean baseline LVMI was 110 +/- 16 g/m2 in male and 96 +/- 16 g/m2 in female patients. It decreased by 3.6% at M3 (P = 0.05) and by 6.0% at M6 (P = 0.02). A trend towards a greater LVMI reduction was observed in previously untreated patients. CONCLUSION: This study confirms that MRI is a reproducible technique for the measurement of LVM. It demonstrates a significant reduction in LVMI as early as the 3rd month of therapy in hypertensive patients treated with once-daily sustained release (SR) diltiazem, although baseline LVMI in the majority of participating patients was only moderately increased.  相似文献   

8.
Contractile performance of hypertrophied left ventricle may be depressed in arterial hypertension. Ventriculoarterial coupling is impaired when myocardial contractile performance is reduced and when afterload is increased. The left ventricular contractile performance and the ventriculoarterial coupling were evaluated in 30 hypertensive patients with moderate left ventricular hypertrophy and 20 control subjects. Left ventricular angiography coupled with the simultaneous recording of pressures with a micromanometer were used to determine end-systolic stress/volume index, the slope of end-systolic pressure-volume relationship, ie, end-systolic elastance, effective arterial elastance, external work, and pressure-volume area. In hypertensive patients, left ventricular contractile performance, as assessed by end-systolic elastance/ 100 g myocardial mass, was depressed (4.35 +/- 1.13 v 5.21 +/- 1.89 mm Hg/mL/100 g in control subjects P < .02), when end-systolic stress-to-volume ratio was comparable in the two groups (3.85 +/- 0.99 g/cm2/mL in hypertensive patients versus 3.51 +/- 0.77 g/cm2/mL in control subjects). Ventriculoarterial coupling, evaluated through effective arterial elastance/end-systolic elastance ratio, was slightly higher in hypertensive patients (0.53 +/- 0.08 v 0.48 +/- 0.09 mm Hg/mL in control subjects, P < .05), and work efficiency (external work/pressure-volume area) was similar in the two groups (0.78 +/- 0.04 mm Hg/mL in hypertensive patients versus 0.80 +/- 0.03 mm Hg/mL in control subjects). This study shows that despite a slight depression of left ventricular contractile performance, work efficiency is preserved and ventriculoarterial coupling is almost normal in hypertensive patients with left ventricular hypertrophy. Thus, it appears that left ventricular hypertrophy might be a useful means of preserving the match between left ventricle and arterial receptor with minimal energy cost.  相似文献   

9.
Effects of antihypertensive therapy on left atrial function   总被引:1,自引:0,他引:1  
OBJECTIVES: To investigate left atrial (LA) function as a reservoir, as a conduit and as a booster pump in essential hypertension (EH). LA volumes were echocardiographically measured in 28 untreated hypertensive patients and in 20 control subjects. BACKGROUND: LA makes a large contribution in left ventricular filling, especially in patients with impaired diastolic function. LA function is fundamental in left ventricular filling in hypertensive patients as hypertension results in left ventricular diastolic dysfunction. METHODS: Diagnosis of EH (blood pressure > 140/90 mm Hg) was based on three repeated readings of blood pressure (BP). Patients with myocardial infarction, cardiomyopathy, valvular or congenital heart disease were excluded. Doppler diastolic early (E) and late (A) velocity of mitral inflow were measured. The following indexes were calculated: left ventricular mass index (LVMI) using the Penn convention; left ventricular stroke volume (LVSV); LA reservoir volume (LARV = LA maximal volume at mitral valve opening minus minimal volume); LA conduit volume (LACV = LVSV-LARV). Atrial systolic function was assessed by calculating the active emptying fraction (volume at onset of atrial systole minus minimal volume/volume at onset of atrial systole, the E/A ratio and the LA ejection force (0.5 rho A2 MOA, where rho = the density of blood, MOA = mitral orifice area from the parasternal short axis view). Measurements were obtained in all hypertensive patients before and after 16 weeks administration of either enalapril (10 or 20 mg) or enalapril +/- chlorthalidone (20/25 mg) once a day. RESULTS: After 16 weeks of treatment, BP was reduced significantly (from 172/110 to 137/86 mm Hg, P < 0.001). LVMI decreased significantly as well (from 141 to 123 g/m2) although it was higher compared to controls (94 g/m2, P < 0.001). LARV decreased significantly (from 35.4 to 29.3 cm3, P < 0.05) while LACV increased significantly (from 43.8 to 51.3 cm3, P < 0.05), LA active emptying fraction and E/A ratio did not change. LA ejection force decreased significantly (from 20.9 to 18.1 kdynes, P < 0.05) but it was greater than controls (16.7 kdynes, P < 0.01). There was a positive relationship of LVMI to LARV (P < 0.01) in controls (r = 0.77) which held true in hypertensive patients, before (r = 0.72) and after treatment (r = 0.69). There was a negative relationship of LVMI to LACV (P < 0.01) in controls (r = -0.65), and in hypertensive patients untreated (r = -0.74) and after treatment (r = -0.72). CONCLUSIONS: Our results showed that in hypertensive patients, LA reservoir function increases and LA conduit function decreases, while LA ejection force increases. Antihypertensive treatment with enalapril and/or thiazide, induces normalisation of the LA function in parallel to left ventricular hypertrophy regression.  相似文献   

10.
BACKGROUND: Left ventricular hypertrophy (LVH) represents an independent risk factor in patients with essential hypertension. Because reversal of LVH may be associated with an improvement of prognosis, the influence of new antihypertensive compounds, such as angiotensin II AT1 receptor antagonists, on LVH should be determined. METHODS AND RESULTS: In a randomized, double-blind trial, 69 predominantly previously untreated hypertensive patients with echocardiographically proven LVH, ie, left ventricular mass index (LVMI) >134 g/m2 in men and >110 g/m2 in women and/or end-diastolic septal thickness >12 mm, received either the angiotensin II antagonist valsartan or atenolol for 8 months. Echocardiographic data of 58 patients were available. After 8 months of valsartan treatment (n=29), LVMI decreased from 127+/-23 to 106+/-25 g/m2 (ratio [R]=0.83; 95% CI, 0.79 to 0.87; P<0.0001 versus baseline). Under atenolol (n=29), LVMI decreased to a smaller extent, from 127+/-25 to 117+/-27 g/m2 (R=0.92; 95% CI, 0.86 to 0.98; P=0.0082 versus baseline). The mean reduction of LVMI came to 21 g/m2 under valsartan and only to 10 g/m2 under atenolol (R=0.91; 90% CI, 0.85 to 0.97 versus atenolol). Baseline mean blood pressure values were determined to be 163+/-12/101+/-6 mm Hg before treatment with valsartan and 160+/-14/103+/-6 mm Hg before atenolol treatment. After 8 months of treatment, mean blood pressure decreased to 146+/-13/90+/-7 mm Hg with valsartan and to 147+/-18/90+/-7 mm Hg with atenolol. Nine patients in the valsartan group and 8 patients in the atenolol group required additional medication with hydrochlorothiazide. CONCLUSIONS: Antihypertensive treatment with the angiotensin II antagonist valsartan for 8 months produced a significant regression of LVH in predominantly previously untreated patients with essential hypertension. The drug may be safely administered in this subset of hypertensive patients; however, the long-term benefit in terms of risk reduction has still to be evaluated in further trials.  相似文献   

11.
Quantitatively assessed ultrasonic backscatter is an index of ultrasonic tissue characterization directly related to morphometrically evaluated collagen in human beings. Our objective was to assess myocardial reflectivity pattern of patients with severe left ventricular hypertrophy caused by either aortic stenosis (AS) or aortic regurgitation (AR). Ten patients with AS, 10 patients with AR, and 10 closely age- and gender-matched healthy controls were studied by two-dimensional Doppler echocardiography. By using an echocardiographic prototype, we performed a radiofrequency analysis to obtain quantitative operator-independent measurements of the integrated backscatter signal of the ventricular septum and the posterior wall (integrated backscatter index: IBI, expressed in percentage). All patients with stenosis or aortic insufficiency showed a normal regional and global resting systolic function (fractional shortening: AS = 36.0 +/- 6.6 versus AR = 40.3 +/- 6.2 versus control = 40.2 +/- 8.7; p = not significant [NS]) Left ventricular mass index (Devereux's formula) was markedly increased in patients with stenosis or aortic insufficiency (AS = 199.3 +/- 18 versus AR = 208.8 +/- 60 versus control = 97.3 +/- 11 g/m2; p < 0.0001). Myocardial echo density was increased in patients with stenosis or aortic insufficiency in comparison with controls, both in the septum (IBI%: AR = 40.7 +/- 7.9 versus AS = 33.4 +/- 4.2 versus control = 23.0 +/- 6.2; p < 0.0001) and in the posterior wall (IBI%: AR = 27.1 +/- 4.3 versus AS = 23.0 +/- 2.6 versus control = 15.0 +/- 4.2; p < 0.0001). No significant correlations were found between septal and posterior wall IBI and their thickness. Abnormally increased myocardial echo density--possibly related to disproportionate collagen deposition--can be detected in patients with pressure or volume overload caused by aortic valve disease and without overt systolic dysfunction.  相似文献   

12.
The operative mortality and morbidity in patients with severe left ventricular dysfunction who undergo coronary artery bypass grafting (CABG) remain high. The low ejection fraction is the major risk factor for operative mortality. However, ejection fraction (EF) alone may not necessarily be an accurate predictor of operative mortality. We studied the correlation between indices of left ventricular volume and operative mortality. One thousand patients undergoing isolated coronary bypass operations were divided into three groups according to their preoperative ejection fraction. Fifty patients (group I) had severe left ventricular dysfunction (EF < or = 0.3), 56 patients (group II) had moderately left ventricular dysfunction (0.3 < EF < or = 0.4) and 894 patients (group III) had good left ventricular function (EF > 0.4). We analyzed the relationship between hospital mortality and left ventricular volume in 106 patients with an EF < or = 0.4. RESULTS: Cardiac index was not significantly different among the three groups. The left ventricular end-diastolic pressure (LVEDP) and mean pulmonary artery pressure in groups I an II were higher than those in group III. The left ventricular end-diastolic volume (LVEDV) was 146 +/- 44 ml/m2 in Group I, 112 +/- 31 ml/m2 in Group II and 82 + 30 ml/m2 in Group III, respectively (Group I versus II, p < 0.05, Group I and II versus III, p < 0.01). The left ventricular end-systolic volume (LVESV) was 111 +/- 38 ml/m2 in Group I, 72 +/- 21 ml/m2 in Group II and 30 +/- 14 ml/m2 in Group III, respectively (Group I versus II, p < 0.05, Group I and II versus III, p < 0.01). The LVEDV and LVESV were higher in Group I than in Group II and both in Groups I and II were higher than in Group III. The hospital mortality of any cause before discharge was 8.0% (4/50) in Group I, 3.6% (2/56) in Group II, and 2.0% (18/894) in Group III. The mortality in Group I was higher than that in Group III, but the mortality between Groups I and II was not different. We assessed correlations between large left ventricle with left ventricular dysfunction and operative mortality in 106 patients with ejection fractions of < or = 0.4. The hospital mortality in patients with both under fraction 0.4 and an LVESV > or = 140 ml/m2 was 50% (4/8). This rate was higher than in patients with an LVESV between 80 and 140 ml/m2 (1.8%, 1/55) (p = 0.0006) and an LVESV less than 80 ml/m2 (2.3%, 1/43), (p = 0.0013). The hospital mortality in patients with an LVEDV > or = 200 ml/m2 was 67% (4/6). It was also higher than that in patients with an LVEDV between 200 and 120 ml/m2 (1.7%, 1/58), (p = 0.0001), and an LVEDV less than 120 ml/m2 (2.4%, 1/42), (p = 0.0004). We conclude that patients with a low ejection fraction and an elevated LVESV or LVEDV are at increased risk for hospital death following CABG.  相似文献   

13.
Aldosterone has been associated with the development of cardiac hypertrophy and a correlation has been found between levels of aldosterone and the degree of cardiac hypertrophy in hypertensive patients. Our study aimed to test the relation between physiologic cardiac hypertrophy and serum aldosterone in a group of highly trained cyclists. Determination of the left ventricular mass index (LVMI) was performed in a group of 40 professional cyclists by using Devereux's formula with correction for body surface area. After an overnight fast, blood samples were collected and serum aldosterone levels were measured using RIA. LVMI and serum aldosterone were intercorrelated using linear regression analysis. Twenty-three of the 40 cyclists (58%) presented an LVMI > 130 g.m-1 and the other 17 subjects (42%) presented an LVMI < 130 g.m-1. Serum aldosterone levels did not correlate with LVMI in either of the groups (LVMI > 130 g.m-1, r = -0.089; LVMI < 130 g.m-1, r = 0.146). The lack of correlation of this hypertrophy with serum aldosterone levels suggests that physiologic hypertrophy of the athlete's heart could be caused by a different stimulus to that seen in pathologic hypertrophy of hypertensives.  相似文献   

14.
PURPOSE: To evaluate QT dispersion in hypertensive patients, with and without left ventricular hypertrophy, and compare with normal persons. METHODS: Thirty eight patients (21 male and 17 female, age 55 +/- 15 years) underwent echocardiography and simultaneous 12 lead, vertically aligned, electrocardiogram at 50 mm/s speed. No patient was on antiarrhythmic therapy. There were 19 non-hypertensive patients that constituted the control group (G-I). Group II was constituted by the other 19 patients, who were hypertensives. This group was further divided in group II-A (9 patients without left ventricular hypertrophy) and group II-B (10 patients with left ventricular hypertrophy). QT dispersion was obtained by the difference between the longest and the shortest QT registered. RESULTS: QT dispersion was significantly increased on hypertensive patients, both with and without left ventricular hypertrophy, when compared to controls (G-I 31 +/- 9 ms, G-II 52 +/- 15 ms. P < 0.0001; G-IIa 46 +/- 10 ms and G-IIb 56 +/- 18 ms X G-I, p < 0.0005). In hypertensive patients, there was no statistically significant difference between group II-A and group II-B. CONCLUSION: We conclude that QT dispersion is significantly increased on hypertensive patients when compared to non-hypertensive individuals and that such increase, occurs before left ventricular hypertrophy develops. These findings suggest that, in hypertensive patients, electrical changes in left ventricular myocardium can precede structural and morphological abnormalities. Such findings offer new insights into the mechanisms related to enhanced mortality among hypertensive patients.  相似文献   

15.
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   

16.
OBJECTIVES: We sought to compare the myocardial velocity gradient (MVG) measured across the left ventricular (LV) posterior wall during the cardiac cycle between patients with hypertrophic cardiomyopathy (HCM), athletes and patients with LV hypertrophy due to systemic hypertension and to determine whether it might be used to discriminate these groups. BACKGROUND: The MVG is a new ultrasound variable, based on the color Doppler technique, that quantifies the spatial distribution of transmyocardial velocities. METHODS: A cohort of 158 subjects was subdivided by age into two groups: Group I (mean [+/-SD] 30 +/- 7 years) and Group II (58 +/- 8 years). Within each group there were three categories of subjects: Group Ia consisted of patients with HCM (n = 25), Group Ib consisted of athletes (n = 21), and Group Ic consisted of normal subjects; Group IIa consisted of patients with HCM (n = 19), Group IIb consisted of hypertensive patients (n = 27), and Group IIc consisted of normal subjects (n = 33). RESULTS: The MVG (mean [+/-SD] s-1) measured in systole was lower (p < 0.01) in patients with HCM (Group Ia 3.2 +/- 1.1; Group IIa 2.9 +/- 1.2) compared with athletes (Group Ib 4.6 +/- 1.1), hypertensive patients (Group IIb 4.2 +/- 1.8) and normal subjects (Group Ic 4.4 +/- 0.8; Group IIc 4.8 +/- 0.8). In early diastole, the MVG was lower (p < 0.05) in patients with HCM (Group Ia 3.7 +/- 1.5; Group IIa 2.6 +/- 0.9) than in athletes (Group Ib 9.9 +/- 1.9) and normal subjects (Group Ic 9.2 +/- 2.0; Group IIc 3.6 +/- 1.5), but not hypertensive patients (Group IIb 3.3 +/- 1.3). In late diastole, the MVG in patients with HCM (Group Ia 1.3 +/- 0.8; Group IIa 1.4 +/- 0.8) was lower (p < 0.01) than that in hypertensive patients (Group IIb 4.3 +/- 1.7) and normal subjects (Group IIc 3.8 +/- 0.9). An MVG < or = 7 s-1, as a single diagnostic approach, differentiated accurately (0.96 positive and 0.94 negative predictive value) between patients with HCM and athletes when the measurements were taken during early diastole. CONCLUSIONS: In both age groups, the MVG was lower in both systole and diastole in patients with HCM than in athletes, hypertensive patients or normal subjects. The MVG measured in early diastole in a group of subjects 18 to 45 years old would appear to be an accurate variable used to discriminate between HCM and hypertrophy in athletes.  相似文献   

17.
The activity of the renin-angiotensin-aldosterone system is thought to play a significant role in the development of target organ damage in essential hypertension. An insertion/deletion (I/D) polymorphism of the angiotensin I-converting enzyme (ACE) gene has recently been associated with increased risk for left ventricular hypertrophy and coronary heart disease in the general population. The D allele is associated with higher levels of circulating ACE and therefore may predispose to cardiovascular damage. The study presented here was performed to investigate the association between the ACE genotype, microalbuminuria, retinopathy, and left ventricular hypertrophy in 106 patients with essential hypertension. ACE gene polymorphism was determined by polymerase chain reaction technique. Microalbuminuria was evaluated as albumin-to-creatinine ratio (A/C) in three nonconsecutive first morning urine samples (negative urine culture) after a 4-wk washout period. Microalbuminuria was defined as A/C between 2.38 to 19 (men) and 2.96 to 20 (women). Hypertensive retinopathy was evaluated by direct funduscopic examination (keith-Wagener-Barker classification) and left ventricular hypertrophy by M-B mode echocardiography. The distribution of the DD, ID, and II genotypes was 27, 50, and 23%, respectively. The prevalence of microalbuminuria, retinopathy, and left ventricular hypertrophy was 19, 74, and 72% respectively. There were no differences among the three genotypes for age, known duration of disease, body mass index, blood pressure, serum glucose, uric acid, and lipid profile. DD and ID genotypes were significantly associated with the presence of microalbuminuria (odds ratio, 8.51; 95% confidence interval, 1.07 to 67.85; P = 0.019), retinopathy (odds ratio, 5.19; 95% confidence interval, 1.71 to 15.75; P = 0.005) and left ventricular hypertrophy (odds ratio, 5.22; 95% confidence interval, 1.52 to 17.94; P = 0.016). Furthermore, patients with DD and ID genotypes showed higher levels of A/C (3.6 +/- 0.9, DD; 2.6 +/- 0.7, ID; 0.9 +/- 0.2 mg/mmol, II; P = 0.0015 by analysis of variance) and increased left ventricular mass index (152 +/- 4.7, DD + ID versus 133 +/- 5.7 g/m2, II; P = 0.01) compared with II patients. The D allele was significantly more frequent in patients with microalbuminuria (odds ratio, 2.59; 95% confidence interval, 1.24 to 5.41; P = 0.013) and in those with retinopathy (odds ratio, 2.44; 95% confidence interval, 1.21 to 4.90; P = 0.015). Multiple regression analyses performed among the entire cohort of patients demonstrated that ACE genotype significantly and independently influences the presence of retinopathy, left ventricular hypertrophy, and microalbuminuria. In conclusion, the D allele of the ACE gene is associated with microalbuminuria as well as with retinopathy and left ventricular hypertrophy, and seems to be an independent risk factor for target organ damage in essential hypertension.  相似文献   

18.
BACKGROUND: The relation between residual myocardial viability after acute myocardial infarction (AMI) and ventricular remodeling has yet to be fully elucidated. We hypothesized that the presence of residual viability would favorably influence left ventricular remodeling after AMI and that serial changes in left ventricular dimensions might be related to the extent of myocardial viability in the infarct zone. METHODS AND RESULTS: Ninety-three patients with a first AMI successfully treated with primary coronary angioplasty underwent two-dimensional echocardiography within 24 hours of admission and low-dose dobutamine echocardiography at a mean of 3 days after AMI. Two-dimensional echocardiography and coronary angiography were obtained in all patients 1 and 6 months after coronary angioplasty. On the basis of dobutamine echocardiography responses, patients were divided in two subsets: those with (n=48; group I) and those without (n=45; group II) infarct-zone viability. There was no difference in minimal lesion diameter and infarct-related artery patency at 1 and 6 months between the two groups. Group II patients had significantly greater end-diastolic (76+/-18 versus 53+/-14 mL/m2; P<.0003) and end-systolic (42+/-17 versus 22+/-11 mL/m2; P<.0003) volumes at 6 months than did patients in group 1. The extent of infarct-zone viability was significantly inversely correlated with percent changes in end-diastolic volumes at 6 months (r=-.66; P<.000001) and was the most powerful independent predictor of late left ventricular dilation. CONCLUSIONS: After reperfused AMI, the degree of left ventricular dilation, when it occurs, is inversely related to the extent of residual myocardial viability in the infarct zone. Thus, the absence of residual infarct-zone viability discriminates patients who develop progressive left ventricular dilation after reperfused AMI from those who maintain normal left ventricular geometry.  相似文献   

19.
Hypertension is a major cause of heart failure, evolving from left ventricular hypertrophy to systolic and diastolic dysfunction. Although effective heart failure therapy has been associated with a lowering or no change in systemic arterial blood pressure in long-term follow-up, this study describes the symptomatic, clinical, and left ventricular functional response of a subgroup of heart failure patients with a prior history of hypertension who demonstrated a paradoxical hypertensive response despite high-dose vasodilator therapy. We prospectively identified 45 patients with a past history of hypertension who had become normotensive with symptomatic heart failure. Of these 45 heart failure patients, 12 became hypertensive while receiving therapy in follow-up, with systolic blood pressure > or = 140 mm Hg (Group A). The remaining 33 patients did not have a hypertensive response to therapy (Group B). In the 12 Group A patients, 60+/-10 years old, with symptomatic heart failure for 6.3+/-4.3 years, vasodilator therapy was intensified in the 2.0+/-0.5 years of follow-up, achieving final doses of enalapril 78+/-19 mg and isosorbide dinitrate 293 +/-106 mg per day. New York Heart Association classification improved from 2.9+/-0.8 to 1.3+/-0.5 (P < or = .0001), with a reduction in heart-failure-related hospitalizations. Left ventricular ejection fraction increased from 17+/-6% to 40+/-10% (P < .0001). Follow-up blood pressure at 1 to 3 months was unchanged. However, both systolic and diastolic blood pressure increased at final follow-up, rising from 116+/-14 to 154+/-13 mm Hg (P = .0001) and from 71+/-9 to 85+/-14 mm Hg (P = .004), respectively. Renal function remained unchanged. Although both groups had similar clinical responses, there were more blacks and women in the hypertensive Group A. Effectively, 12 of 45 (27%) heart failure patients with an antecedent history of hypertension demonstrated a paradoxical hypertensive response to vasodilator therapy. The recurrence of hypertension in a significant portion of patients successfully treated for heart failure has important clinical implications.  相似文献   

20.
To determine the contribution of cardiac renin-angiotensin system (RAS) to the physiological myocardial hypertrophy induced by swimming training and the relationship between locally produced and circulating RAS, both ventricular and plasma angiotensin (Ang) I and II contents, ventricular angiotensin converting enzyme (ACE) and plasma renin activity (PRA) were detected by means of radioimmunoassay and biochemical method. It was shown that after 5 weeks of swimming, the ventricular wet weight to body weight ratio (V/Bwt) and Ang II in both left and right ventricles and ACE activity increased markedly as compared with the controls (P < 0.05). Furthermore, significantly positive correlation was found between the ventricular Ang II and V/Bwt (r = 0.7721, P < 0.001), while the plasma Ang I and II and PRA remained at the control level. No correlation was found between plasma Ang II and V/Bwt. These above findings suggest that cardiac RAS may play an important role in physiological myocardial hypertrophy and to a large extent is in dependent on circulating RAS.  相似文献   

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