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1.
The aim of the present study was to analyze heart function in subclinical hyperthyroidism (sHT) in otherwise healthy subjects by new methods using intramyocardial ultrasonic techniques. Twenty-four newly diagnosed and untreated sHT patients (20 women, 4 men; mean age: 42+/-4 yr) and 24 sex- and age-matched healthy volunteers were studied. All subjects were submitted to conventional 2D color-Doppler echocardiography, pulsed wave tissue Doppler imaging (PWTDI) for the analysis of diastolic function, color Doppler myocardial imaging (CDMI) for the analysis of regional strain and strain rate (SR) expression of regional myocardial deformability, and to integrated backscatter (IBS) for the evaluation of intrinsic contractility and tissue characterization. Regional myocardial systolic strain findings were significantly higher in sHT patients when compared with controls (p<0.001). Considering diastolic SR, the early phase of diastolic SR was compromised in sHT subjects as compared with controls (p<0.001). Cyclic variation index (CVI), expression of intrinsic contractility, was significantly higher in sHT subjects in comparison with controls (p<0.0001). IBS values were comparable between the 2 study groups. In conclusion, the present study suggests that in patients with sHT early systolic hyperdeformability and hypercontractility are present, together with impairment of both active and passive phases of diastole. On the contrary, no left ventricular hypertrophy or other structural alterations are documented.  相似文献   

2.
It is not known if diastolic abnormalities are independent of systolic dysfunction in arterial hypertension. We studied three groups of 10 male subjects of comparable mean age (31.6 +/- 3.5 years), weight, and height: Athletes (A) (cyclists), essential hypertensive patients (H), and controls (C). Ultrasonic myocardial integrated backscatter signals (IBS) of the septum and the posterior wall were analyzed, while the systo-diastolic variation of the backscatter was considered as a cyclic variation index (CVI(ibs)). Myocardial velocities across the left ventricular major axis were sampled at septum and lateral wall levels by pulsed-wave Doppler tissue imaging (DTI). CVI(ibs) at the septum and the posterior wall were significantly lower in the hypertensive group in comparison with athletes and controls, who were comparable. Early diastolic myocardial velocity (E(m)) of the lateral wall and of the septum were significantly lower in hypertensives, while the late diastolic myocardial velocity (A(m)) was significantly higher in hypertensives in comparison with athletes. The E(m)/A(m) at the septum level was significantly lower in hypertensives in comparison with athletes and controls. Significant correlations were found between CVI and DTI parameters: CVI(ibs) and E(m)/A(m) septum (r = 0.50, P < 0.002). Furthermore, significant correlations were found between mean arterial pressure (MAP) and E(m)/A(m) septum (r = - 0.65, P < 0.001). Ultrasonic tissue characterization with the intrinsic contractility study and the evaluation of the regional diastolic function should, therefore, represent a new integrated diagnostic modality for the evaluation of left ventricular hypertrophied intramyocardial function. This study demonstrated that diastolic abnormalities of left ventricular function, in arterial hypertension, are related and progress with systolic intrinsic dysfunction.  相似文献   

3.
The new echocardiographic techniques for the study of physiopathological intramyocardial phenomena include video densitometry (VD), integrated backscatter (IBS), and color Doppler myocardial imaging (CDMI). Being more independent from cardiac load and from rotational and translational heart motion, these new sensible, noninvasive techniques such as CDMI and IBS show a real incremental value in comparison with conventional echocardiography and allow to detect subtle functional and textural abnormalities of intramural myocardium, partially undetectable by conventional two-dimensional Doppler echocardiography. Subclinical thyroid dysfunction (STD), both in its hypo- and hyperthyroidism form, has a relatively high prevalence in general population (9–15% with a lower percentage of adult males), hence it could be very useful to study more deeply heart involvement in these physiopathological conditions and understand the complex relationship between thyroid and heart. The use of these new ultrasonic techniques in subclinical hypothyroidism helps to detect the early simultaneous involvement of both cardiac cycle phases, which causes a decrease of intramyocardial contractility and an impairment of both active and passive phases of diastole. In subclinical hyperthyroidism, these new ultrasonic techniques permitted to discover more complex and different early cardiac abnormalities of both systolic and diastolic phases.  相似文献   

4.
BACKGROUND: Heart abnormalities are frequent findings in patients with acromegaly: systolic abnormalities are considered to be secondary to diastolic changes. AIM: The aim of the study was to evaluate whether early systolic abnormalities might be revealed in acromegalic patients using the high sensitive color Doppler myocardial imaging (CDMI) technique. PATIENTS AND METHODS: Twenty-two consecutive acromegalic patients with active untreated disease (ACROUNTR) were evaluated at baseline and after a 6-month course with SS analogs (SSa) (ACROSSa); 25 healthy subjects served as controls. All subjects underwent conventional 2D-color Doppler echocardiography, pulse wave tissue Doppler imaging (PW-TDI) and CDMI. RESULTS: Mean left ventricular (LV) ejection fraction did not differ in ACROUNTR and in controls; at variance, ACROUNTR patients had reduced mean LV diastolic function (E/A ratio: 0.96+/-0.3 vs controls: 1.6+/-0.3; p<0.002). Impairment of global LV diastolic function was confirmed by PW-TDI in ACROUNTR patients having a normal systolic function. Regional myocardial systolic strain (epsilon) and strain rate (SR) values, indices of regional systolic heart deformation, were lower in ACROUNTR [epsilonsys (S) -19.8+/-2.9 and epsilonsys (L): -17.7+/-2.2] than in controls [epsilonsys (S): -27.9+/-3.8; p<0.001 and epsilonsys (L): -25.3+/-2.6; p<0.001]. In addition, the early phase of diastolic function, evaluated using SR parameters, was impaired in acromegalic patients (p<0.005 vs controls). Strain and SR values were related to serum GH and IGF-I levels (p<0.02) and greatly improved after a 6-month course with SSa [epsilonsys (S) improved to -23.8+/-3.8 (p<0.05) and epsilonsys (L) improved to -24.7+/-2.4 (p<0.03)]. CONCLUSIONS: Our study confirms that ACROUNTR patients have impaired diastolic function. More important, our study clearly shows that ACROUNTR patients have an impairment of regional myocardial systolic function, which is not secondary to diastolic changes. These intramyocardial functional abnormalities improved during medical treatment of acromegaly. It is conceivable that GH-IGF-I excess has detrimental effects either on the diastolic or the systolic phases of heart function.  相似文献   

5.
Subclinical hypothyroidism (sHT) affects 5-15% of the general population; however, the need of lifelong L-T(4) therapy is still controversial. As myocardium is a main target of thyroid hormone action, we investigated whether sHT induces cardiovascular alterations. Twenty sHT patients were randomly assigned to receive placebo or L-T(4) therapy and were followed for 1 yr. Twenty sex- and age-matched normal subjects served as controls. Doppler echocardiography and videodensitometric analysis were performed in all subjects. Myocardium textural parameters were obtained as mean gray levels, which were then used to calculate the cyclic variation index (CVI; percent systolic/diastolic change in mean gray levels). Patients had a significantly higher isovolumic relaxation time (3.1 +/- 0.5 vs. 2.6 +/- 0.6; P < 0.03), peak A (0.77 +/- 0.16 vs. 0.56 +/- 0.13 m/s; P < 0.01), and preejection/ejection time (PEP/ET) ratio (0.72 +/- 0.05 vs. 0.57 +/- 0.06; P < 0.03) and a lower CVI (P < 0.0001) than controls. CVI was inversely related to TSH level (P < 0.0001) and PEP/ET ratio (P < 0.01). L-T(4)-treated patients showed a significant reduction of the PEP/ET ratio (P < 0.05), peak A (P < 0.05), and isovolumic relaxation time (P < 0.05) along with a normalization of CVI. Conversely, no changes were observed in the placebo-treated group. In conclusion, sHT affects both myocardial structure and contractility. These alterations may be reversed by L-T(4) therapy.  相似文献   

6.
BACKGROUND: Survival of patients with PAIVS has improved significantly with adoption of a selective management approach based on RV and coronary arterial anatomy. We sought to determine the right (RV) and left ventricular (LV) function of patients with pulmonary atresia and intact ventricular septum (PAIVS) long-term after biventricular repair. METHODS: The regional ventricular function of 22 patients (11 males) aged 12.8+/-5.6 years with PAIVS after biventricular repair was assessed by tissue Doppler echocardiography (TDE). The results were compared to those of 22 age-matched controls. RESULTS: When compared with controls, patients had significantly reduced myocardial tissue velocities, systolic and diastolic strain rate, and peak systolic strain in the basal, mid-, and apical segments of the RV free wall, interventricular septum and LV lateral wall (all with p<0.01). Heterogeneity of systolic and diastolic strain rate was observed in the RV free wall and interventricular septum in patients but not in controls. CONCLUSION: Impairment of RV and LV regional longitudinal myocardial function occurs in patients with PAIVS late after biventricular repair.  相似文献   

7.
BACKGROUND: Acromegalic patients have increased left ventricular (LV) mass (M) and impaired diastolic function. AIM: Using ultrasonic cardiac tissue characterization, we evaluated the early changes in cardiac fibrosis (IBS) and intrinsic myocardial contractility (CVI) as well as their reversibility after treatment with somatostatin analogues (SMSA) in patients with acromegaly. PATIENTS AND METHODS: Twenty-two acromegalic patients with active untreated disease (Acro(UNTR)) underwent conventional Doppler echocardiography and integrated backscattering; 25 healthy subjects (controls) and eight patients with acromegaly in remission after pituitary adenomectomy (Acro(REM)) served as controls. RESULTS: As expected, Acro(UNTR) at baseline had higher LVM than controls or Acro(REM) (P < 0.001); LVM reduced in acromegalic patients after SMSA (P < 0.005 vs. baseline) while LV ejection fraction did not change. LV diastolic function was reduced in all acromegalic patients, either at baseline or after SMSA therapy (E/A ratio, 0.96 +/- 0.3 and 1.1 +/- 0.3, respectively, P < 0.002 vs. controls, 1.6 +/- 0.3). CVI was reduced in Acro(UNTR) (14.3 +/- 5.8%, P < 0.003 vs. controls, 28.7 +/- 7.5%) and greatly improved after SMSA (22.5 +/- 4.5%, P < 0.003 vs. baseline). Cardiac fibrosis was increased in Acro(UNTR) (IBS(MSI), 53.7 +/- 5.3%P < 0.002 vs. controls) and reduced after SMSA (43.7 +/- 4.2%P < 0.002 vs. baseline) albeit not reaching values observed in controls. More importantly, five of 22 (23%) Acro(UNTR) patients had normal LVM, but increased cardiac fibrosis as revealed by back scattering. IBS values and CVI% were related with serum GH and IGF-1 (P < 0.0001) levels, and the estimated duration of disease (P < 0.005). CONCLUSIONS: The present study demonstrated that active acromegalic patients had early impairment of systolic function and increased cardiac fibrosis; increased fibrosis may precede LV hypertrophy; these changes are related to the activity of disease and might improve during treatment with SMSA.  相似文献   

8.
BACKGROUND: The aim of this study was to evaluate the relationship between insulin resistance and preclinical abnormalities of the left ventricular structure and function detected in severe obesity by Color Doppler Myocardial Imaging (CDMI). Forty-eight consecutive severely obese patients (Group O) (11 males, 37 females, mean age 32.8+/-7 years) were enrolled. Forty-eight sex- and age-matched non-obese healthy subjects were also recruited as controls (Group C). All subjects underwent conventional 2D-Color Doppler echocardiography and CDMI. The homeostasis model assessment insulin resistance index (HOMA-IR) was used to assess insulin resistance results. Obese subjects had a greater left ventricular mass index (by height) (58.8+/-14 g/m(2.7)) than controls (37+/-8 g/m(2.7)) (P<0.0001), owing to compensation response to volume overload caused by a greater cardiac output (P<0.02). Preload reserve was increased in obese subjects, as demonstrated by a significant increase in left atrial dimension (P<0.0001). Obese patients had a slightly reduced LV diastolic function (transmitral E/A ratio: Group O, 1.1+/-0.8 vs Group C, 1.5 +/-0.5; P<0.002). Cardiac deformation assessed by regional myocardial systolic strain and strain rate (SR) values was significantly lower (abnormal) in obese patients than in controls, both at the septum and lateral wall level. These strain and SR abnormalities were significantly related to body mass index. In addition, the early phase of diastolic function, evaluated using SR, was compromised in obese patients (P<0.001). The HOMA-IR values in obese patients were significantly higher (3.09+/-1.6) than those determined in the control group (0.92+/-0.5) (P<0.0001). The HOMA-IR values, in the obese group, were significantly related to systolic strain and SR values sampled at the septum level (P<0.0001). CONCLUSION: In conclusion, this study has demonstrated that obese patients pointed out systolic structural and functional abnormalities at a preclinical stage, in particular through strain and SR analysis; on the other hand, those altered CDMI parameters well distinguish obese subjects as compared with the control group. Furthermore, another main finding of the study was that myocardial deformation (systolic strain) could have a correlation with insulin resistance level.  相似文献   

9.
The aim of this study was to determine whether early myocardial structural and functional systolic and diastolic alterations in asymptomatic and uncomplicated patients with type 1 diabetes mellitus (DM) could be detected using the new highly sensitive echocardiographic techniques of integrated backscatter and color Doppler myocardial imaging. Forty asymptomatic and uncomplicated patients with type 1 DM and 40 gender- and age-matched normal controls were studied. All patients were analyzed by conventional and new echocardiographic techniques (integrated backscatter and color Doppler myocardial imaging). Patients with DM showed reduced systolic function compared with controls, evidenced by significantly lower peak strain, strain rates, and cyclic variation indexes at the septum (p <0.0001, <0.01, and <0.001, respectively) and at the posterior wall level (p <0.0001, <0.0001, and <0.001, respectively). On receiver-operating characteristic curve analysis, systolic strain and the cyclic variation index showed the highest discriminating power for separating patients with DM and control subjects. Neither structural or ultrastructural nor diastolic functional abnormalities were detected. On univariate regression analysis, a significant inverse correlation was found for DM duration with conventional (E/A ratio) and unconventional (tissue Doppler imaging E/A ratio) indexes of diastolic function, in the absence of any correlation for systolic function. In conclusion, highly sensitive ultrasonic techniques demonstrate evidence of left ventricular systolic dysfunction in the early stage of type 1 DM, in the absence of ultrastructural and left ventricular diastolic functional abnormalities.  相似文献   

10.
Use of myocardial tissue Doppler imaging in cardiology   总被引:3,自引:0,他引:3  
Tissue Doppler imaging is a new promising method of non-invasive assessment of cardiac function. This method has heralded a renaissance of interest in longitudinal ventricular function. There is evidence that long-axis function is a more sensitive index of myocardial contractility than conventional echocardiographic parameters, and that therefore, this technique could contribute to early diagnosis of systolic dysfunction. Tissue Doppler imaging can be successfully applied in the assessment of regional myocardial function. It has been proven that myocardial velocities truly reflect structural myocardial changes (the degree of myocardial fibrosis) and beta-adrenoreceptor density. The use of tissue Doppler imaging in concert with stress echocardiography is also extremely encouraging and is considered as the most likely solution to the problem of quantitative analysis of stress echocardiography. The method additionally opens new horizons in non-invasive assessment of diastolic function of the heart. Myocardial velocities have been shown to have important advantages over conventional Doppler indices of left ventricular diastolic filling. Frustration among cardiologists caused by unreliability of the traditional approach in the assessment of diastolic properties of the heart seems to have been overcome. Tissue Doppler imaging allows the examination of right ventricular systolic and diastolic function, the differentiation between constrictive pericarditis and restrictive cardiomyopathy and the estimation of pressures in cardiac chambers and in the pulmonary artery. It can also establish the presence of accessory conduction pathways, the diagnosis of rejection of transplanted hearts and can be used for identification of indications for biventricular pacing. Although many clinicians believe that tissue Doppler imaging is still an experimental technique, it can now be introduced into the routine practice of echocardiographic laboratories. The wider use of the method will help to develop its benefits and better understand and overcome limitations.  相似文献   

11.
BACKGROUND: Angiotensin II receptor antagonists have recently been accepted as antihypertensive therapy. Tissue Doppler imaging (TDI) has been developed as a noninvasive tool to assess quantitatively regional myocardial motion abnormalities. This study was designed to determine whether our newly developed technique of color-coded TDI may be a useful means of quantifying the improvement in regional left ventricular (LV) myocardial contractility and relaxation after treatment with losartan in patients with hypertension. METHODS AND RESULTS: Losartan (50 to 100 mg) was administered for 6 months to 37 previously untreated patients with essential hypertension. Averaged myocardial velocity profiles (MVPs) for color-coded TDI were recorded in the ventricular septum and LV posterior wall before and after treatment. Peak myocardial velocities and peak myocardial velocity gradients (MVGs) in the LV walls were determined during systole and early diastole. The plasma concentration of transforming growth factor (TGF)-beta1 also was measured in all patients. Blood pressure and plasma TGF-beta1 level decreased after initiation of losartan therapy. The LV mass index and LV meridional end-systolic wall stress also decreased after treatment with losartan. LV geometry changed from a pattern consistent with concentric hypertrophy to normal geometry in 10 patients and to a pattern consistent with concentric remodeling in 5 patients, and from concentric remodeling to normal geometry in 5 patients after treatment with losartan. The ratio of early to late diastolic filling for the transmitral flow velocity increased after losartan treatment. The peak systolic and early diastolic myocardial velocities and MVGs in the ventricular septum and LV posterior wall increased after treatment with losartan, although the values 6 months after treatment with losartan were still lower than those in normal individuals. There were good correlations between changes in plasma TGF-beta1 level and changes in systolic and early diastolic MVGs 6 months after losartan. However, there were no significant correlations between changes in the systolic blood pressure and LV end-systolic wall stress and changes in the TDI parameters. CONCLUSION: Losartan improves regional LV function in patients with hypertension. Our newly developed averaged MVP and MVG measurements may be useful for accurately evaluating regional LV myocardial contractility and relaxation in these patients.  相似文献   

12.
AIMS: Hypertrophic cardiomyopathy (HCM) is a disease with marked regional differences in wall thickness. However, the relation between myocardial function and wall thickness has not been well studied. Ultrasonic strain rate (SR) imaging makes it possible to study the regional myocardial deformation. We investigated whether regional systolic deformation is reduced in paediatric patients with HCM and evaluated its relation with wall thickness, electrocardiographic pattern, and exercise capacity. METHODS AND RESULTS: We studied 41 children with asymmetric HCM (mean age 12.3 years) and 29 controls. Electrocardiograms, exercise testing (when feasible), and echocardiograms with tissue Doppler imaging were performed. Peak systolic SR, strain, post-systolic shortening, and time to maximal strain were calculated in the longitudinal direction from the basal septum, mid-septum, and basal lateral myocardial segments and in the radial direction from the basal antero-septal and infero-lateral myocardial segments. Children with HCM had a significant reduction in deformation in all myocardial segments when compared with controls. In the HCM group, peak systolic SR and strain were significantly lower in the basal septum when compared with the mid-septal and basal lateral myocardial segments. In the basal septum, post-systolic shortening was significantly higher and time to maximal strain significantly longer than in mid-septal and lateral myocardial segments. A strong inverse curvilinear relation between peak systolic strain and wall thickness was found (r = -0.86, P < 0.001), with no further decrease in the regional myocardial function demonstrated once maximal wall thickness exceeded a Z-score of 3.5. Peak systolic strain in the basal part of the septum correlated inversely with exercise capacity (r = 0.68, P < 0.01). CONCLUSION: Systolic deformation is significantly and inhomogeneously reduced in children with HCM. This reduction in myocardial function is related to maximal wall thickness and decreased exercise capacity.  相似文献   

13.
Background and aimsPediatric obesity is an important health problem representing a major public health concern worldwide in the last decades. An isolated elevation of Thyroid Stimulating Hormone (TSH) with normal levels of thyroid hormones is frequently found in obese children. It has been named Isolated Hyperthyreotropinemia or Subclinical Hypothyroidism (SCH) and may be considered a consequence of obesity. Evidence exists that SCH is related to impairment of both systolic and diastolic myocardial function in the adult population.The aim of our study is to establish if obesity-related SCH influences myocardial function in children.Methods and resultsWe examined 34 obese children and adolescents with SCH and 60 obese children with normal TSH levels who underwent Doppler echocardiographic to evaluate myocardial function.Global systolic function as assessed by Ejection Fraction (EF) was comparable between groups, however Right Ventricle pressure global systolic function and pressure were significantly reduced in SCH group. Mitral annulus peak systolic (MAPSE) excursion lateral and MAPSE septum resulted significantly reduced in SCH group. Tissue Doppler imaging peak systolic motion (TDI-S) was reduced in SCH group. Diastolic function also showed significant modifications in SCH group.ConclusionThese results suggest possible involvement of cardiac function in obese children with SCH resulting in both abnormal diastolic function and reduced longitudinal systolic function. This new insight into cardiovascular consequences of obesity-related SCH in children could influence clinical approach to such patients by pediatric endocrinologists.  相似文献   

14.
目的采用组织多普勒(TDI)成像技术评价老年单纯舒张功能不全患者左心室长轴收缩功能的变化。方法选取老年无症状舒张功能不全患者(老年ADD组)157例、老年舒张性心力衰竭患者(老年DHF组)130例及健康老年人(正常对照组)89例,应用TDI成像技术测量二尖瓣环水平左心室室间隔、侧壁、前壁、下壁心肌长轴方向收缩期心肌峰值运动速度(Sm);Simpson法测量左心室射血分数(LVEF)。结果与正常对照组比较,老年ADD组与老年DHF组二尖瓣环水平心肌侧壁、前壁、下壁Sm值、Sm均值及老年DHF组室间隔Sm值显著降低(P<0.05~0.001),且老年DHF组Sm值降低幅度更大(P<0.05~0.001)。结论老年单纯舒张功能不全患者存在左心室长轴收缩功能降低,Sm较LVEF能更敏感地检测到轻度收缩功能不全的存在。  相似文献   

15.
The objective was to compare velocity information derived from either a tissue mimicking phantom or normal contracting myocardium by both pulsed wave and color Doppler myocardial imaging (PWDMI and CDMI). Both CDMI and PWDMI allow quantitative assessment of regional myocardial contraction and relaxation velocities, but their potential clinical applications have not yet been investigated. Moreover, no information is available as to whether they can be used interchangeably for regional velocity assessment. For the in vitro study, a rotating, circular-shaped, tissue-mimicking sponge driven by a motor at speeds of 15, 30, 60, 90 rpm was used to derive velocity data from the same eight points of interest by using PWDMI or CDMI techniques. For the in vivo study, 25 normal subjects were examined at rest using parasternal and apical approaches. Velocity profiles were derived from the same 26 areas of interest (18 left ventricular segments, 3 right ventricular segments, and 5 measurement points for the tricuspid and mitral annuli) for each technique. Peak maximal velocities were detected by PWDMI and peak mean velocities were measured using CDMI. The results of the in vitro study phantom showed excellent correlation (r = 0.99, P < 0. 001) and satisfactory agreement (0.04 cm/sec; 3.3 cm/sec) between both Doppler techniques. PWDMI velocities were higher than CDMI velocities by up to 20% and overestimated the real velocity value (0. 37 +/- 0.29 cm/sec) while CDMI underestimated predicted velocity by 1.35 +/- 0.36 cm/sec. Good correlation (r = 0.87, P < 0.001), but poor agreement (-2.1 cm/sec; 5.4 cm/sec) was shown in vivo for all segments with regard to peak systolic and diastolic velocities. Both Doppler techniques cannot be used interchangeably for comparing peak velocities in the clinical situation. However, with adequate temporal resolution, they can be used interchangeably for velocity profile recording and for timing of events.  相似文献   

16.
AIMS: Systemic sclerosis (SSc) is a connective tissue disorder characterized by frequent myocardial involvement. Alteration in left ventricular (LV) function is reported to be rare; however, it may be underestimated by conventional measurements. Our aim was to prospectively investigate LV function in SSc patients, using Tissue Doppler echocardiography (TDE), a modern and accurate method of assessing myocardial function. METHODS AND RESULTS: Seventeen consecutive SSc patients with normal cardiac examination, pulmonary artery pressure (PAP) and radionuclide LV ejection fraction (EF) were prospectively investigated. Myocardial perfusion was investigated using single-photon-emission computerized tomography (SPECT). Echocardiography (ECHO), systolic and diastolic strain-rate (SR) measured in the posterior wall by TDE were used to investigate myocardial function, and compared with results of 15 matched controls. All patients (53+/-8 years; 14 women; systolic PAP 33+/-6 mmHg; LVEF 67+/-8%) had myocardial SPECT perfusion abnormalities. Despite normal ECHO, they had lower systolic SR than controls (1.7+/-0.5 versus 3.8+/-1.7 cm-1, p<0.0001), and lower diastolic SR (3.7+/-1.5 versus 5.6+/-1.2 cm-1, p=0.0004). Ten SSc patients had reduced systolic SR<1.7 cm-1 and 11 reduced diastolic SR<3.5 cm-1. CONCLUSION: Frequent abnormal myocardial perfusion is confirmed in SSc patients. Reduced contractility is also frequent as detected by TDE, despite normal radionuclide LVEF.  相似文献   

17.
Chagas' disease can lead to severe and potentially lethal damage of cardiac function. Thus, the identification of contractile abnormalities in asymptomatic patients can be important for risk stratification in those patients. Doppler tissue imaging (DTI) is a new diagnostic modality for the study of regional and longitudinal contractility of the left ventricle. However, DTI has not been used for the assessment of Chagas' cardiopathy. The purpose of this study was to identify abnormalities related to longitudinal contractility by means of DTI in patients with an undetermined form of Chagas' disease and with normal echocardiogram and Doppler studies. Forty patients were studied, including 21 chagasic ones with normal electrocardiographic, radiologic, and echocardiographic studies, and 19 normal control individuals. All of the patients were submitted to DTI to evaluate longitudinal contractility in the various myocardial segments, including assessment of systolic and diastolic velocities and isovolumic contraction time (IVCT). Similar values were observed among the various systolic function rates in both groups, except for the IVCT along the septal wall, which was significantly higher in the chagasic group. DTI enabled the early detection of contractile abnormalities in patients with an undetermined form of Chagas' disease and with normal echocardiogram. Such abnormalities were particularly striking in the interventricular septum. The present study could be useful in risk stratification for those patients.  相似文献   

18.
Tissue Doppler imaging and strain rate imaging are quantitative methods for assessing myocardial function and have been shown to overcome the limitations of current ultrasound methods in assessing the complex changes in regional myocardial function that occur in differing ischemic substrates. Tissue Doppler imaging (TDI) measures in real time the myocardial velocity gradient which is an index of myocardial deformation. Strain and strain rate (SR) imaging has been shown to be a sensitive technique for quantifying regional myocardial deformation. Strain rate is less load-dependent that strain and provides therefore a better measure of contractility. In the setting of ischemia, experimental studies have shown that strain imaging was an accurate method for quantitative evaluation of regional myocardial function and may yield important physiological data. In myocardial infarction, transmural extension of scar distribution in the infarct zone is proportionally related to the reduction in systolic function measured by the radial transmural velocity gradient or by strain rate imaging. Measurement of both systolic and post-systolic deformation both at rest and during a graded dobutamine infusion may help to distinguish between transmural and non transmural infarcts. In conclusion, strain imaging has the ability to evaluate of regional myocardial function. Strain rate has not replaced conventional grey-scale imaging in the assessment of regional left ventricular function and the implement of these new indices in the routine clinical practice will need additional clinical and large-scale studies.  相似文献   

19.
多普勒组织成像对正常人左心室收缩功能的分析   总被引:4,自引:0,他引:4  
目的 :应用多普勒组织成像脉冲技术评价正常人左心室整体收缩功能。研究二尖瓣环舒缩速度与左心室整体收缩功能间的相关性 ,以及观察二尖瓣环舒缩速度与左心室射血分数间是否存在直线回归关系。方法 :转换多普勒组织成像速度模式 ,取心尖四腔心、二腔心、心尖左心室长轴切面 ,分别测量二尖瓣环后间隔、侧壁、前壁、下壁、前间隔及后壁的舒张早期峰值速度 (E)、舒张晚期峰值速度 (A)、收缩期峰值速度 (S)。应用改良Simpson法测量左心室射血分数。结果 :左心室射血分数与二尖瓣环前间隔S、E与肺静脉D波比值 (E/D) ,后间隔S ,前壁与后壁的E/D存在直线相关关系。结论 :多普勒组织成像测量二尖瓣环舒缩速度可反映左心室整体收缩功能。并且发现左心室收缩功能不仅与二尖瓣环收缩速度有关 ,而且与舒张速度也相关。二尖瓣环前间隔是反映这一现象的最好位点。  相似文献   

20.
INTRODUCTION: The long-term follow-up of patients with D-transposition of the great arteries after atrial switch operation shows specific problems such as tricuspid valve insufficiency, rhythm disturbances and failure of the morphologic right ventricle in systemic position. Assessment of the myocardial contractility of the subaortic right ventricle by conventional echocardiography is limited. The usage of tissue Doppler echocardiography with strain combined with strain rate imaging provides a new approach for quantitative analysis of longitudinal myocardial function. The aim of this study was to assess patterns of wall motion and regional contractile function of the systemic right ventricle in patients after atrial switch operation for D-transposition of the great arteries and to compare them to those of normal subjects. PATIENTS AND METHODS: Twenty-four patients with Dtransposition of the great arteries after atrial switch operation with a mean age of 21.3 (range, 13 to 31) years and a postoperative period of 16.9 years were examined and compared to 22 control individuals with a mean age of 21.5 (range, 3 to 43) years. Tissue Doppler studies were obtained from apical 4- chamber view to determine regional systolic (Syst(T)) and diastolic (E(T), A(T)) velocities as well as E(T)/A(T) ratio at the basal free wall. The presystolic isovolumic contraction peak was assessed and the ratio of the presystolic peak velocity to the isovolumic acceleration time as the IVA index was calculated. Strain and peak systolic and diastolic strain rates were assessed on basal, middle and apical segments of the right ventricular free wall. Data obtained from the morphologic right systemic ventricle in patients were compared to those derived from the left and the right ventricle in controls. RESULTS: The right ventricular free wall systolic velocities were significantly reduced in patients compared to velocities obtained from the normal right and left ventricle. On the other hand, the IVA index was only reduced in patients compared to the IVA index in the normal subpulmonary right ventricle. Compared to data obtained from the normal systemic left ventricle, the IVA index in patients was not significantly different. In contrast, strain and strain rate parameters in all analyzed segments mostly showed a highly significant reduction compared to normal right and left ventricular data. CONCLUSION: Tissue Doppler echocardiography is a promising tool for the evaluation of regional myocardial contractile function of the morphologic right systemic ventricle in patients following atrial switch operation for D-transposition of the great arteries. Presystolic, systolic and diastolic regional ventricular function was reduced in the systemic right ventricle. However, further comparative studies using other quantitative parameters of global and regional myocardial function derived from cardiac catheterization or MRI should be performed in order to evaluate the reliability of tissue Doppler echocardiography for the assessment of global right ventricular function in these patients.  相似文献   

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