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1.
We investigated whether left ventricular (LV) structural or functional abnormalities persist in children on long-term follow-up after successful correction of coarctation of the aorta. Two-dimensional directed M-mode and Doppler echocardiographic examinations were performed in 11 such subjects and 22 age-matched control subjects. Digitized tracings were made from M-mode recordings of the LV and Doppler mitral valve inflow recordings to measure septal, posterior wall, and LV dimensions, LV mass, shortening fraction, peak shortening and lengthening velocities, diastolic filling time, peak E velocity, peak A velocity, and velocity time integrals. Despite group similarities in age, body size, and systolic blood pressure, greater fractional shortening (p = 0.0001), indexed peak shortening velocity (p less than 0.001), and greater LV mass index (p less than 0.05) were seen in the coarctation group in the face of lower LV wall stress (p = 0.0001). LV mass index correlated with the resting arm-leg gradient, which ranged from -4 to +10 mm Hg. The coarctation group had decreased early filling (p less than 0.006) with compensatory increased late diastolic filling (p less than 0.05). Diastolic filling abnormalities were prominent in the older coarctation subjects and were related to both systolic blood pressure (p less than 0.001) and LV mass index (p less than 0.01). Despite apparently successful repair of coarctation of the aorta, persistent alterations in both systolic and diastolic LV function and LV mass are present in children at long-term follow-up, which are related to the resting arm-leg gradient.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

2.
The study investigated the temporal relationship between left ventricular (LV) relaxation and filling during early diastole. The transmitral flow (TMF) velocity by pulsed Doppler echocardiography and LV wall motion velocity by pulsed tissue Doppler imaging (TDI) were evaluated in 57 patients with various heart diseases and 33 normal controls. The patients were classified into 2 groups according to the ratio of the peak early diastolic to atrial systolic TMF velocity (E/A): (1) the high A group included 44 patients with an E/A < or = 1, and (2) the pseudonormalization group included 13 patients with an E/A > 1. The isovolumic relaxation time (IRT) from the aortic component of the second heart sound (IIA) to the onset of the E wave of the TMF was measured. The peak early diastolic velocity of the LV posterior wall (Ew) and time from the IIA to the onset of the early diastolic wave (IIA-Ewo) were determined from the LV wall motion velocity assessed by pulsed TDI. The Ew was lower in the pseudonormalization and high A groups than in the control group. The IIA-Ewo was significantly longer in the pseudonormalization and high A groups than in the control group. The time constant of the LV pressure decay at isovolumic diastole (tau) correlated negatively with the Ew, and correlated positively with the IIA-Ewo in all groups. The IIA-Ewo was equal to or shorter than the IRT in control subjects, and was longer than the IRT in patients in the pseudonormalization group. In conclusion, the temporal relationship between LV relaxation and filling during early diastole varied according to the subjects' hemodynamic status. Analysis of TMF by pulsed Doppler echocardiography and LV wall motion velocity by pulsed TDI was useful for detailed evaluation of early diastolic LV hemodynamics.  相似文献   

3.
To assess left ventricular (LV) diastolic function in children with systemic hypertension, 11 patients with hypertension (mean blood pressure 99 mm Hg) and 7 normal patients (mean blood pressure 78 mm Hg) underwent M-mode echocardiography and pulsed Doppler examination of the LV inflow. From a digitized trace of the LV endocardium and a simultaneous phonocardiogram, echocardiographic diastolic time intervals, peak rate of increase in LV dimension (dD/dt), and dD/dt normalized for LV end-diastolic dimension (dD/dt/D) were measured. Doppler diastolic time intervals, peak velocities at rapid filling (E velocity) and atrial contraction (A velocity), and the ratio of E and A velocities were measured. The following areas under the Doppler curve and their percent of the total area were determined: first 33% of diastole (0.33 area), first 50% of diastole, triangle under the A velocity (A area), and the triangle under the E velocity (E area). The A velocity (patients with hypertension = 0.68 +/- 0.11 m/s, normal subjects = 0.49 +/- 0.08 m/s), the 0.33 area/total area (patients with hypertension = 0.49 +/- 0.09, normal subjects = 0.58 +/- 0.08), the A area (patients with hypertension = 0.17 +/- 0.05, normal subjects = 0.12 +/- 0.03), and the A area/total area (patients with hypertension = 0.30 +/- 0.11, normal subjects = 0.20 +/- 0.07) were significantly different between groups (p less than 0.05). M-mode and Doppler time intervals, (dD/dt)/D, E velocity, and the remaining Doppler areas were not significantly different between groups.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

4.
To analyze the relation of systolic anterior motion (SAM) of the mitral valve, peak left ventricular (LV) outflow tract velocity, aortic flow and mitral flow, 17 patients with obstructive hypertrophic cardiomyopathy (HC) (8 men, 9 women), aged 19 to 88 years (mean 45), were studied using M-mode and 2-dimensional echocardiography and pulsed and continuous-wave Doppler echocardiography and results were compared with those from 18 age-matched normal subjects. SAM was present in all patients with HC and absent in normal subjects. Time to peak outflow velocity as a percentage of LV ejection time was 63% in patients with HC and 29% in normal subjects (p less than 0.001). In 13 patients, time from the R-wave peak to the closest approximation of the mitral valve to the ventricular septum or initial contact during SAM was determined and was 242 +/- 66 ms and time from the R-wave peak to the peak LV outflow tract velocity was 242 +/- 73 ms (r = 0.90). In 11 patients time from the R-wave peak to cessation of flow in the ascending aorta was measured and was 286 +/- 80 ms; time from the R-wave peak to the peak LV outflow tract velocity was 246 +/- 75 ms. The ratio of early to late diastolic filling velocities of the left ventricle was 1.47 +/- 0.40 in the normal subjects and 1.26 +/- 0.84 in patients with HC (difference not significant). The early to late ratio of the 12 patients without mitral regurgitation was 0.99 +/- 0.52 (p less than 0.01 vs normal subjects).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

5.
OBJECTIVES: To determine the short-term effects of cardiac resynchronization therapy (CRT) on measurements of left ventricular (LV) diastolic function in patients with severe heart failure. BACKGROUND: Cardiac resynchronization therapy improves systolic performance; however, the effects on diastolic function by load-dependent pulsed-wave Doppler transmitral indices has been variable. METHODS: Fifty patients with severe heart failure were evaluated by two-dimensional Doppler echocardiography immediately prior to and 4 +/- 1 month after CRT. Measurements included LV volumes and ejection fraction (EF), pulsed-wave Doppler (PWD)-derived transmitral filling indices (E- and A-wave velocities, E/A ratio, deceleration time [DT], diastolic filling time [DFT], and isovolumic relaxation time). Tissue Doppler imaging was used for measurements of systolic and diastolic (Em) velocities at four mitral annular sites; mitral E-wave/Em ratio was calculated to estimate LV filling pressure. Color M-mode flow propagation velocities were also obtained. RESULTS: After CRT, LV volumes decreased significantly (p < 0.001) and LVEF increased >5% in 28 of 50 patients (56%) and were accompanied by reduction in PWD mitral E-wave velocity and E/A ratio (both p < 0.01), increased DT and DFT (both p < 0.01), and lower filling pressures (i.e., E-wave/Em septal; p < 0.01). Patients with LVEF response < or =5% after CRT had no significant changes in measurements of diastolic function; LV relaxation (i.e., Em velocities) worsened in this group. CONCLUSIONS: In heart failure patients receiving CRT, improvement in LV diastolic function is coupled to the improvement in LV systolic function.  相似文献   

6.
We studied the structural and functional heart adaptations of 52 male triathletes compared with those of 22 active, nonathletic men, by 2-dimensional Doppler echocardiography. Left ventricular diastolic function was evaluated by recording transmitral flow velocities. To exclude the influences of preload, left atrial pressure, and aortic pressure, left ventricular diastolic function was also evaluated by pulsed Doppler tissue imaging. Significant differences in cardiac structure and function were observed between the 2 groups. In the triathletes, the left ventricular diastolic function was completely normal, despite signs of mixed eccentric and concentric left ventricular hypertrophy, and this function was better than that in the control group. We measured 2 aspects of the late passive diastolic filling period in the triathletes: ASEAC value (the amplitude of excursion of the interventricular septal endocardium at the end of left ventricular diastole just after atrial contraction); and the time between onset of the P wave on the electrocardiographic tracing and onset of systolic septal movement on M-mode echocardiography. Pulsed Doppler tissue imaging confirmed these results. The E/A ratios (peak early left ventricular diastolic motion velocity divided by the peak atrial systolic motion velocity), measured by pulsed Doppler tissue imaging, yielded even more evidence for supernormal left ventricular diastolic function in the triathletes. Left ventricular relaxation and filling properties were measured along the longitudinal and transverse axes by pulsed Doppler tissue imaging, which was useful for evaluating left ventricular diastolic function. We determined that triathletes may develop supernormal left ventricular diastolic function with increased diastolic reserves.  相似文献   

7.
多普勒组织成像评价正常人心肌舒缩运动速度   总被引:8,自引:0,他引:8  
目的 探讨心肌舒缩运动变化的相关因素。方法 标准切面 (左心室长轴、短轴 )用脉冲多普勒组织成像(DTI)测定室间隔、前壁、下后壁的内膜下心肌及外膜下心肌运动峰值速度。结果 各个室壁及各层心肌收缩期 s峰值速度不相同。内膜下心肌的 s峰值速度大于外膜下心肌的 s峰值速度 ,室间隔左心室面 s峰值速度大于右心室面 s峰值速度 ,两者间存在速度阶差。长轴左心室后壁 s峰值速度大于室间隔 s峰值速度 ,短轴后壁 s峰值速度大于前壁 s峰值速度。 s峰值速度与年龄无相关 ,舒张期 a峰值速度与年龄呈中度相关 ,e/ a比与年龄呈中度负相关 ,室壁运动的 e/ a比与二尖瓣血流 E/ A比呈中度相关。结论 脉冲 DTI可用于评价心肌的舒缩功能  相似文献   

8.
The aim of this study was to assess the effects of endurance training on myocardial regional systolic and diastolic function by pulsed Doppler tissue imaging (DTI). Twenty male water polo players and 20 male control subjects underwent standard Doppler echocardiography and pulsed DTI, performed in apical views by placing a sample volume on left ventricular (LV) basal septal and inferior walls. Age, body surface area, and blood pressure were comparable between the 2 groups, with lower heart rate in athletes (p <0.001). They had significantly increased LV mass index (due to both higher wall thickness and end-diastolic diameter), greater endocardial fractional shortening, higher transmitral early/atrial (E/A) peak velocities ratio. In athletes, DTI analysis showed significantly prolonged myocardial deceleration time and greater myocardial E/A peak velocity ratio of septal and inferior walls, whereas myocardial early peak velocity was increased (p <0.01) only at the inferior wall. In the overall group, we found univariate relations of septal and inferior E/A peak velocity ratio and myocardial deceleration time with LV mass levels, and, in particular, with the sum of wall thickness. By separate multivariate analyses, however, these relations disappeared, being dependent on heart rate degree. Another association found between LV end-diastolic diameter and myocardial early diastolic wave peak velocity of the inferior wall (r = 0.68, p <0.0001) remained significant (standardized beta coefficient 0.60, p <0.00001), even after adjusting for heart rate, body surface area, age, and stroke volume (R(2) = 0.71, p <0.00001). In conclusion, DTI is a useful tool for detecting regional changes in myocardial function induced by training, because athletes present with an improvement in diastolic passive properties of myocardium. The higher early diastolic velocity of the inferior wall and its relation to increased preload may represent an indicator of aerobic training, allowing quantification of the degree of LV adaptation to endurance exercise.  相似文献   

9.
In order to assess the value of Doppler tissue imaging (DTI) in the differentiation of physiological hypertrophy of athletes from primary hypertrophic cardiomyopathy (HCM), the authors compared a group of 20 normal, non-athletic subjects, a group of 43 competitive athletes and a group of 20 patients with mild HCM. In addition to the conventional echocardiographic criteria, the velocity of wall motion at the endocardium and epicardium of the interventricular septum and the posterior wall as well as their gradients, were measured throughout the cardiac cycle. No significant difference was observed between normal subjects and the athletes with respect to velocities and the gradients of velocity. Early diastolic velocities of the posterior wall and interventricular septum were significantly lower than those of normal subjects and athletes. The systolic and early diastolic gradients of velocity of the posterior wall were significantly lower in HCM compared with the normal subjects and athletes. The gradient of velocity between the endocardium and epicardium of the interventricular septum was significantly lower in HCM compared with normal subjects in early diastole and with athletes in systole and early diastole. The best Doppler tissue imaging parameter to differentiate pathological hypertrophy of HCM from physiological hypertrophy of athletes was analysis of the gradient of velocity in early diastole of the posterior wall. A value of 0.7 sec-1 differentiated HCM with a sensitivity of 89%, a specificity of 95% and a diagnostic accuracy of 94%. Doppler tissue imaging is a more sensitive and specific technique than conventional Doppler echocardiography for detecting moderate forms of HCM.  相似文献   

10.
Abnormal left ventricular diastolic properties have been described in patients with hypertrophic cardiomyopathy. To evaluate the diastolic filling characteristics of the left ventricle in patients with this disease, pulsed Doppler echocardiography was used to study mitral flow velocity in 17 patients with hypertrophic cardiomyopathy (11 with and 6 without systolic anterior motion of the mitral valve) and 16 age-matched normal subjects. There were no statistically significant differences between patients with hypertrophic cardiomyopathy with and without systolic anterior motion with regard to ventricular septal thickness, left ventricular posterior wall thickness, left ventricular internal dimensions or the extent of hypertrophy evaluated by two-dimensional echocardiography. Mitral regurgitation was detected by Doppler echocardiography in all 11 patients with and in 2 (33%) of the 6 patients without systolic anterior motion of the mitral valve. Early and late diastolic peak flow velocity, the ratio of late to early diastolic peak flow velocity and deceleration of early diastolic flow were measured from Doppler mitral flow velocity recordings. There were no statistically significant differences in these four indexes between the patients with systolic anterior motion and normal subjects. In contrast, the patients with hypertrophic cardiomyopathy without systolic anterior motion showed lower early diastolic peak flow velocity, higher ratio of late to early diastolic peak flow velocity and lower deceleration of early diastolic flow compared with the patients with systolic anterior motion and normal subjects, suggesting impaired left ventricular diastolic filling.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

11.
To characterize the cardiovascular consequences of a history of hypertension in first-degree relatives in normotensive young adults, 72 normotensive (diastolic blood pressure [BP] less than 90 mm Hg) healthy volunteers (age 18 to 30 years) were studied with 2 dimensionally guided M-mode echocardiography, pulsed Doppler echocardiography, and 2-hour automated BP monitoring. Of the 72 subjects, 19 (12 men and 7 women) had a family history of hypertension and were compared with 19 subjects without a family history of hypertension who were matched for systolic BP and gender. There were no detectable differences in 2-hour average BP, left ventricular (LV) mass or wall thickness, or echocardiographic systolic functional indexes between subjects with and without a family history of hypertension. Doppler-derived diastolic functional indexes demonstrated more prominent late diastolic filling in subjects with a family history of hypertension. Late diastolic transmitral flow time and flow velocity integral were greater (132 +/- 24 vs 117 +/- 17 ms, p less than 0.05; and 2.5 +/- 0.7 vs 1.9 +/- 0.5 cm, p less than 0.01, respectively). To measure possible gender-related effects of a family history of hypertension, the men and women were analyzed separately. The 12 men with a family history of hypertension had greater peak late (40 +/- 0.9 vs 31 +/- 0.8 cm/s, p less than 0.02) and ratio of late-to-early (0.64 +/- 0.19 vs 0.46 +/- 0.10, p less than 0.01) transmitral flow velocities and greater late transmitral flow velocity integrals (2.6 +/- 0.8 vs 1.9 +/- 0.5 cm, p less than 0.05) than the matched male control subjects.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

12.
The purpose of the present study was to examine the mechanisms of improvement in left ventricular (LV) diastolic function in hypertensive patients treated with cilnidipine, a new and unique calcium antagonist that has both L-type and N-type voltage-dependent calcium channel blocking actions, using pulsed Doppler echocardiography and pulsed tissue Doppler imaging. The study comprised 35 untreated patients with essential hypertension (19 men and 16 women; mean age 65+/-10 years). The peak early diastolic and atrial systolic transmitral flow velocities (E and A, respectively) and their ratio (E/A), and the peak early diastolic and atrial systolic motion velocities (Ew and Aw, respectively) of the LV posterior wall and their ratio (Ew/Aw) were determined in all patients before and after 1, 3 and 6 months on cilnidipine (10 mg/day). One month: Systolic and diastolic blood pressures were significantly decreased. E and E/A were significantly increased, whereas there were no significant changes in Ew and Ew/Aw. Three months: Ew and Ew/Aw were significantly increased compared to those before and 1 month after cilnidipine. Six months: E and E/A were significantly increased compared with before and 3 months after cilnidipine, and Ew and Ew/Aw were significantly increased compared with before cilnidipine. Moreover, the LV mass index was significantly decreased compared to that before cilnidipine. In summary, changes in LV diastolic performance in patients with essential hypertension following cilnidipine treatment were biphasic with an initial increase in early diastolic transmitral flow velocity and a later increase in early diastolic LV wall motion velocity. The initial and later changes can be related to an acute change in afterload and a later improvement in LV relaxation.  相似文献   

13.
14.
OBJECTIVES: Myocardial contractility of the left ventricle along the long axis in hypertensives is not well characterized. The systolic velocities of the left ventricular myocardium along the long axis were measured by pulsed tissue Doppler imaging in patients with mild to moderate essential hypertension. The relationships between the systolic velocity of left ventricular myocardium along the long axis and the blood pressure, and the left ventricular geometry were investigated. METHODS: The study included 60 untreated hypertensive patients (hypertension group) and 59 age-matched healthy subjects (control group). M-mode echocardiograms were recorded, and the relative wall thickness, left ventricular mass index and left ventricular end-systolic stress were calculated. The peak systolic velocities of the left ventricular posterior wall motion (Sw) were measured by pulsed tissue Doppler imaging. RESULTS: The Sw was significantly lower in the hypertension group than in the control group (8.3 +/- 1.9 vs 9.2 +/- 2.0 cm/sec, p < 0.05). The Sw was correlated inversely with systolic blood pressure (r = -0.31, p < 0.005), diastolic blood pressure (r = -0.25, p < 0.0001), interventricular septal thickness (r = -0.41, p < 0.0001), left ventricular posterior wall thickness (r = -0.39, p < 0.0001), relative wall thickness (r = -0.33, p < 0.001), and left ventricular mass index (r = -0.37, p < 0.001) in all subjects. CONCLUSIONS: The systolic velocity of the left ventricular myocardium along the long axis is decreased in patients with mild to moderate essential hypertension, and is negatively correlated with blood pressure and the severity of left ventricular concentric hypertrophy.  相似文献   

15.
BACKGROUND: Pulsed Wave Tissue Doppler (PWTD) recording of myocardial velocities has been widely used for assessing ventricular function but the output trace has finite thickness that leads to potential ambiguity in determining velocity and timing. OBJECTIVE: To determine optimal method of measurement of PWTD traces by comparing them with those obtained from digitised M-mode recorded from the atrioventricular (AV) valve ring (septal, LV and RV free wall). METHODS: We studied 100 subjects, 49 normal and 51 with coronary artery disease (15 patients with reduced left ventricular wall motion, mean systolic amplitude of LV free wall 0.8+/-0.3 cm), mean age 53+/-15 years. We recorded AV ring motion using PWTD and M-mode echo techniques. PWTD velocity signals were measured separately at: outer, inner and mid-points of the envelope and compared with peak velocities obtained from digitised M-mode long axis. RESULTS: Peak systolic (S), early diastolic (E) and late diastolic (A) PWTD velocities at outer, inner and middle envelope correlated closely with the corresponding M-mode measurements at left, septal and right ventricular free wall. However, only the midpoint S and E wave PWTD signal velocities agreed numerically with those obtained by digitised M-mode velocities; S (left 6.56+/-1.80 vs. 6.54+/-1.91 cm/s N.S.); E (left 8.50+/-3.25 vs. 7.65+/-3.30 cm/s N.S.). Agreement was somewhat less satisfactory for A wave; left 7.40+/-2.13 vs. 6.23+/-2.09 cm/s p<0.05. CONCLUSION: Atrioventricular valve ring echo provides an excellent in vivo calibration model for validating tissue Doppler velocity estimates. Since the mid-point of the envelope of the tissue Doppler signal is the most closely related value to that of the digitised M-mode, it may be recommended as a convention for routine practice.  相似文献   

16.
Doxorubicin (Adriamycin) is an effective anticancer agent but its therapeutic value is limited by its myocardial cardiotoxicity. To improve early detection of doxorubicin cardiotoxicity, studies were performed in patients with long-term doxorubicin treatment using pulsed Doppler echocardiography to assess the changes in left ventricular (LV) diastolic filling dynamics. M-mode echocardiographic systolic parameters and Doppler transmitral flow velocities were analyzed in two groups of patients. In group A (45 patients, mean age 45 +/- 13 years), the results were compared with those of a control group of 35 normal subjects matched for age. In group B (19 patients, mean age 44 +/- 12 years), the pretreatment results were prospectively compared with those obtained during treatment protocol. The patients received a cumulative dosage of 253 +/- 125 mg/m2 of doxorubicin for group A and 240 +/- 135 mg/m2 for group B. After doxorubicin treatment, in the two groups there were no significant changes in LV dimensions, shortening fraction, and mean velocity of circumferential fiber shortening (VCF). In contrast, Doppler echocardiographic parameters of diastolic function were significantly modified after doxorubicin in the two groups:isovolumic relaxation period was prolonged by 32% in group A (p less than 0.001) and by 22% in group B (p less than 0.005).2+ The early peak flow velocity was reduced by 18% in group A (p less 0.002) and by 13% in group B (p less than 0.04), and the ratio early peak flow velocity/atrial peak flow velocity also decreased significantly, by 23% in group A (p less than 0.001) and by 20% in group B (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

17.
Peak early diastolic left ventricular (LV) filling rate has been used as an index of LV diastolic function. However, it is known to be affected by LV size. Peak early diastolic transmitral flow velocity measured by pulsed Doppler echocardiography has also been proposed as a noninvasive method of assessing LV diastolic function. To determine if peak early diastolic mitral flow velocity also is influenced by LV size, 20 normal neonates (age 2 days) and 21 normal adults (mean age 38 years) were studied using pulsed Doppler echocardiography to measure mitral flow velocity and M-mode echocardiography to estimate LV end-diastolic volume and mitral valvular area. Peak early diastolic LV filling rate was calculated by multiplying peak early diastolic mitral flow velocity by mitral valvular area. Adults had significantly larger LV end-diastolic volumes (mean +/- standard deviation 108 +/- 25 vs 7 +/- 3 ml) and higher peak early diastolic LV filling rates (305 +/- 75 vs 29 +/- 10 ml/s) than neonates (both p less than 0.001). However, no significant difference was found in peak early diastolic mitral flow velocity between adults and neonates (61 +/- 10 vs 58 +/- 11 cm/s). These data suggest that peak early diastolic mitral flow velocity is independent of LV size. Since peak LV filling rate is equal to the product of peak mitral flow velocity and mitral valvular area, the correlation between peak early diastolic LV filling rate and LV size is probably due to differences in mitral valvular area rather than differences in peak mitral flow velocity.  相似文献   

18.
To determine left ventricular (LV) structural and functional changes induced by ultraendurance exercise training, M-mode LV echograms and Doppler recordings of LV inflow velocity in 26 triathletes and 17 normal subjects were studied. All triathletes trained 20 to 40 hours/week in swimming, cycling and running for more than 2 years. Structurally, triathletes had normal LV systolic and diastolic cavity dimensions, but increased wall thickness (1.05 +/- 0.26 vs 0.80 +/- 0.27 cm in normal subjects, p less than 0.001), increased relative wall thickness, or h/R ratio (0.41 +/- 0.10 cm vs 0.33 +/- 0.11 cm in normal subjects, p less than 0.001), and increased LV mass (226 +/- 60 vs 143 +/- 54 g in normal subjects, p less than 0.001). LV mass correlated closely with mean exercise blood pressure during an 8-hour exercise test in 14 triathletes (r = 0.88). Systolic function at rest was similar in both groups, with no differences in fractional shortening or end-systolic stress. Diastolic LV function measured by digitized M-mode echo was similar in normal subjects and triathletes, with no differences in peak rates of cavity enlargement and wall thinning by echocardiogram. In contrast, the Doppler-derived ratio of early-to-late LV inflow velocities was slightly increased in triathletes (p less than 0.05). It is concluded that ultraendurance training produces a physiologic pattern of moderate pressure overload LV hypertrophy, in proportion to the hemodynamic load imposed during prolonged exercise. Unlike the abnormal hypertrophy of systemic hypertension, early diastolic function remains normal in the triathlete heart.  相似文献   

19.
Normative Doppler values and determinants of left ventricular (LV) diastolic function in healthy subjects have not been fully elucidated. Subjects from the Framingham Heart Study were examined to describe reference values and determinants of echocardiographic Doppler indexes of diastolic function. One hundred twenty-seven randomly selected, rigorously defined, normal subjects, approximately evenly distributed by sex and age from the third through the eighth decades were studied by Doppler echocardiography. Normative values for 7 frequently used Doppler indexes of LV diastolic function are presented. Doppler indexes of LV diastolic function change dramatically with age; the peak velocity of early filling divided by late filling (peak velocity E/A) ranges from a mean of 2.08 +/- 0.55 for subjects in their third decade to 0.84 +/- 0.29 for those in their eighth decade. A peak velocity E/A ratio less than 1 is abnormal in subjects aged less than 40 years, but occurs in most subjects aged greater than or equal to 70 years. The high correlations between age and Doppler indexes of LV diastolic function are not greatly attenuated after adjustment for other clinical parameters associated with diastolic function; the multivariate partial correlation coefficient between age and peak velocity E/A is -0.80 (p less than 0.0001). Heart rate, PR interval, LV systolic function, sex and systolic blood pressure are minor determinants of Doppler indexes of diastolic function. Body mass index, left atrial diameter, and LV wall thickness, internal dimension and mass have little or no association with Doppler indexes in healthy subjects.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

20.
The objective of the present study was to evaluate the hemodynamic relationship between the left atrium (LA) and left ventricle (LV) during atrial systole in the presence of an elevated left ventricular end-diastolic pressure (LVEDP) and LV failure using pulsed tissue Doppler imaging (TDI). Fifty-three patients with LV systolic dysfunction and no regional LV asynergy were divided into 3 groups: relaxation failure group (RF, n=20) with a ratio of peak early diastolic to atrial systolic velocity of the transmitral flow (E/A) < or = 1; pseudonormalization group (PN, n=19) with 1 or =2. In addition, 20 normal patients (E/A > or = 1) were studied as a control group. The transmitral and pulmonary venous flow velocities were recorded by transesophageal pulsed Doppler echocardiography. The wall motion velocity patterns were recorded at the middle portion of the LV posterior wall (LVPW) and at the mitral annulus (MA) of the LVPW site in the apical LV long-axis view by transthoracic pulsed TDI. The LVEDP was significantly greater in the PN and RS groups than in the RF and control groups. The moan pulmonary capillary wedge pressure was greatest in the RS group. The percent fractional change of the LA area during atrial systole determined by 2-dimensional echocardiography was significantly lower in the RS group than in the PN group. The peak atrial systolic pulmonary venous flow velocity was significantly greater in the PN group than in the RS group. The peak atrial systolic motion velocity (Aw) at the LVPW was significantly lower in the PN and RS groups than in the RF and control groups. The Aw at the MA was significantly lower in the RS group than in the other groups. There was no significant difference in Aw between the LVPW and MA in the RS group, whereas Aw at the MA was significantly greater than that at the LVPW in the PN group. In conclusion, the measurements of Aw at the LVPW and MA can be used to noninvasively evaluate the hemodynamic relationship between the LA and LV during atrial systole in patients with LV failure.  相似文献   

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