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1.
Doppler tissue imaging is a new technique of measuring the velocities of myocardial wall motion. In order to assess its value in the diagnosis of acute rejection, the velocities of the interventricular septum and left ventricular posterior wall were measured in systole and early diastole in 34 cardiac transplant patients at the time of their endomyocardial biopsy, using an M mode left parasternal short axis view. During 40 episodes of acute rejection (26 mild and/or moderate, 10 sub-severe and 4 severe), the wall velocities decreased significantly (p < 0.001) both in the interventricular septum and endocardium of the posterior wall. Myocardial velocities were significantly slower in sub-severe or severe rejection than in mild or moderate rejection. The most sensitive criterion was the measurement of posterior wall endocardial velocity in early diastole, a decrease of 10% having a sensitivity of 92% whereas the sensitivity of usual Doppler echocardiographic parameters is only 73%. Acute rejection, even mild cases, can be diagnosed with excellent sensitivity by measuring myocardial velocities by Doppler tissue imaging. This technique has the advantage of being non-invasive, reproducible and reliable in the follow-up of cardiac transplant patients.  相似文献   

2.
The aim of this study was to assess a Doppler-echocardiographic parameter which has not been previously reported for the diagnosis of acute cardiac rejection. The parameter was left ventricular isovolumic relaxation blood flow. Eighty patients who had undergone orthoptic cardiac transplantation were followed up regularly with echocardiography for a period of 2 years. In all, 495 echocardiographic studies were performed and the results compared with those of endomyocardial biopsy performed on the same day (11.4 echocardiographic studies per patient). In the absence of cardiac rejection, isovolumic relaxation Doppler signal was recorded in all patients (364/387 echo studies). This was a positive signal directed towards the apex detected by continuous mode Doppler in the apical position, arising along the interventricular septum in the mid part of the left ventricle (82% of cases) or from the basal region of the septum (18% of cases) and lasting throughout the phase of isovolumic relaxation. The maximal velocity was 0.53 +/- 0.08 m/s (range 0.32 to 0.73 m/s) : the velocity-time integral was 34 +/- 33 cm. This signal was associated with medioventricular endosystolic acceleration of blood flow in 75% of cases. The incidence of the isovolumic relaxation flow signal decreased in cardiac rejection with no significant changes in the other usual Doppler-echocardiographic parameters except for a significant decrease in the ejection fraction in the group with severe rejection. In the group with mild rejection (n = 89) an isovolumic relaxation flow signal was only observed in 52 cases (including 29 in whom immunosuppressive treatment was not increased). In patients with moderate rejection (n = 12) there were only 5 cases in which a isovolumic relaxation flow signal was recorded, and in the group with severe rejection (n = 7), the signal could only be recorded in 1 case. The authors conclude that the absence of an isovolumic relaxation blood flow signal in a cardiac transplant patient is a reliable sign of cardiac rejection with an excellent specificity (94%). The absence of this signal is a sensitive indicator of severe rejection (86%) but less so for moderate (58%) or mild rejection (42%).  相似文献   

3.
OBJECTIVES: The purpose of this study was to determine whether left atrial size and ejection fraction are related to left ventricular filling pressures in patients with coronary artery disease. BACKGROUND: In patients with coronary artery disease, left ventricular filling pressures can be estimated by using Doppler mitral and pulmonary venous flow velocity variables. However, because these flow velocities are age dependent, additional variables that indicate elevated left ventricular filling pressures are needed to increase diagnostic accuracy. METHODS: Echocardiographic left atrial and Doppler mitral and pulmonary venous flow velocity variables were correlated with left ventricular filling pressures in 70 patients undergoing cardiac catheterization. RESULTS: Left atrial size and volumes were larger and left atrial ejection fractions were lower in patients with elevated left ventricular filling pressures. Mean pulmonary wedge pressure was related to mitral E/A wave velocity ratio (r = 0.72), left atrial minimal volume (r = 0.70), left atrial ejection fraction (r = -0.66) and atrial filling fraction (r = -0.66). Left ventricular end-diastolic and A wave pressures were related to the difference in pulmonary venous and mitral A wave duration (both r = 0.77). By stepwise multilinear regression analysis, the ratio of mitral E to A wave velocity was the most important determinant of pulmonary wedge (r = 0.63) and left ventricular pre-A wave (r = 0.75) pressures, whereas the difference in pulmonary venous and mitral A wave duration was the most important variable for both left ventricular A wave (r = 0.75) and left ventricular end-diastolic (r = 0.80) pressures. The sensitivity of a left atrial minimal volume > 40 cm3 for identifying a mean pulmonary wedge pressure > 12 mm Hg was 82%, with a specificity of 98%. CONCLUSIONS: Left atrial size, left atrial ejection fraction and the difference between mitral and pulmonary venous flow duration at atrial contraction are independent determinants of left ventricular filling pressures in patients with coronary artery disease. The additive value of left atrial size and Doppler variables in estimating filling pressures and the possibility that left atrial size may be less age dependent than other mitral and pulmonary venous flow velocity variables merit further investigation.  相似文献   

4.
A noninvasive method to detect heart transplant rejection would allow for increased monitoring at reduced risk. Automatic border detection is a new method to assess diastolic abnormalities. The purpose of this study was to determine whether automatic border detection of left ventricular filling detects rejection in children. Nineteen episodes of biopsy-proven rejection in 10 children were retrospectively reviewed. Echocardiograms during rejection were compared with those before rejection and during recovery. Automatic border detection indices were percentage of total left ventricular filling as a result of rapid filling, diastasis, and atrial contraction. The percentage of total ventricular filling during diastasis increased significantly during rejection (10% +/- 6% versus 15% +/- 8%, p = 0.02), and the percentage of filling during the rapid filling phase decreased during rejection (82% +/- 8% versus 77% +/- 11%, p = 0.08). These changes were even more marked for the most severe episodes of rejection. These changes resolved at recovery. Automatic border detection of left ventricular filling patterns are altered during cardiac rejection in children. Filling during diastasis increases significantly, and filling during the rapid filling phase decreases. A prospective analysis is needed to determine whether these changes in filling can obviate the need for cardiac biopsy.  相似文献   

5.
The aim of this study was to determine the role of Doppler echocardiography in establishing the prognosis of Stages to 4 cardiac failure. The echocardiographic indices of left ventricular filling were correlated with catheter data and the 2 year out come of patients. The study population included 54 patients examined prospectively in the context of an evaluation of their cardiac failure. Two years after the initial examination, 19 patients were dead or transplanted. Of the remaining 35 patients, 18 were reevaluated at 6 months. Of the echocardiographic parameters, "hyper normal" mitral flow with a high E/A ration indicated poor prognosis; when E/A > 2, the one year survival was 50% and the 2 year survival 42%. There was overlap between the groups of dead or transplanted and surviving patients only when the E/A ratio was between 2 and 3. The patients with E/A < 2 were all alive without any major events at 2 years. All patients with E/A > 3 had a poor prognosis. The E/A ratio was closely correlated with pulmonary capillary pressure levels (p < 0.001, r = 0.55) and lees closely with cardiac index (p < 0.05, r = 0.4) and radionuclide ejection fraction (p < 0.05, r = 0.28). After 6 months' vasodilator treatment with an angiotensin converting enzyme inhibitor (captopril) the E/A ratio decreased significantly from 1.85 +/- 0.78 to 1.0 0.55 (p < 0.02). A "hyper-normal" mitral flow is related to many factors, including high left ventricular filling pressures, mitral regurgitation and reduced left ventricular compliance. This appearance of mitral flow is a poor prognosis factor in severe cardiac failure.  相似文献   

6.
To assess left ventricular diastolic filling in mitral valve prolapse (MVP), we studied 22 patients with idiopathic MVP and 22 healthy controls matched for sex, age, body surface area and heart rate. A two-dimensional, M-mode and Doppler echocardiographic examination was performed to exclude any cardiac abnormalities. The two groups had similar diastolic and systolic left ventricular volumes, left ventricle mass and ejection fraction. Doppler measurements of mitral inflow were: E and A areas (the components of the total flow velocity-time integral in the early passive period of ventricular filling, E; and the late active period of atrial emptying, A), the peak E and A velocities (cm.s-1), acceleration and deceleration half-times (ms) of early diastolic rapid inflow, acceleration time of early diastolic flow (AT), total diastolic filling time (DFT) (ms), and the deceleration of early diastolic flow (cm.s-2). From these measurements were calculate: peak A/E ratio (A/E), E area/A area, the early filling fraction, the atrial filling fraction, AT/DFT ratio. All the Doppler measurements reported are the average of three cardiac cycles selected at end expiration. The mean peak A velocity, A/E velocity ratio, deceleration half time and atrial filling fraction were each significantly higher for subjects presenting a MVP (60 +/- 12 cm.s-1 vs 49 +/- 14, P < 0.008; 98 +/- 13% vs 64 +/- 12%, P < 0.0001; 120 +/- 36 ms vs 92 +/- 11, P < 0.002; 0.45 +/- 0.14 vs 0.36 +/- 0.08, P < 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

7.
8.
Velocity-encoded cine MRI (VEC-MRI) can measure volume flow at specified site in the heart. This study used VEC-MRI to measure flow across the mitral valve to compare the contribution of atrial systole to left atrial filling in normal subjects and patients with left ventricular hypertrophy. The study population consisted of 12 normal subjects (mean age 34.5 years) and nine patients with various degrees of left ventricular hypertrophy resulting from aortic stenosis (mean age 70 years). VEC-MRI was performed in double-oblique planes through the heart to measure both the mitral inflow velocity pattern (E/A ratio) and the volumetric flow across the mitral valve. The left atrial contribution to left ventricular filling (AC%) was calculated. The results were compared with Doppler echocardiographic parameters. The VEC-MRI-derived mitral E/A ratios showed a significant linear correlation with E/A ratios calculated from Doppler echocardiography (r = 0.94), and the VEC-MRI-derived E/A ratios (2.1 +/- 0.5 vs 1.0 +/- 0.4) and AC% values (24.9 +/- 7.2 vs 45.7 +/- 16.4) were significantly different between normal subjects and patients with aortic stenosis (p < 0.01 in both groups). The same differences were seen in the Doppler echocardiographic parameters. The VEC-MRI-derived E/A ratio and AC% showed significant hyperbolic and linear correlations with left ventricular mass indexes (r = 0.95 and 0.86). In addition, the VEC-MRI-determined E/A ratio and the volumetric AC% displayed a highly significant hyperbolic correlation (r = 0.95). Thus VEC-MRI can be used to evaluate left ventricular diastolic filling characteristics in normal subjects and patients with abnormalities of diastolic filling.  相似文献   

9.
Eleven children who received transplants at less than 2 years of age underwent 59 echocardiograms at the time of endomyocardial biopsy for the assessment of the ability of echocardiography to predict acute rejection in the infant heart transplant recipient. Two patients died of acute rejection and autopsy findings were compared with premortum echocardiograms. Biopsy specimens were graded as no rejection (n = 46), mild rejection (cellular infiltrate, n = 5), or moderate-severe rejection (myocyte necrosis/edema, n = 8). Echocardiographic indexes measured included the following: left ventricular mass, left ventricular volume, ejection fraction, heart rate, and peak rate of posterior wall thinning. Compared with controls, patients during mild rejection had slower posterior wall diastolic thinning (p < 0.01). No significant change was noted in left ventricular mass until endomyocardial biopsy specimens showed severe rejection. No significant changes were noted in heart rate or ejection fraction in any of the groups. In conclusion, decrease in the peak rate of posterior wall diastolic thinning may be a sensitive indicator of acute rejection in the infant heart transplant recipient.  相似文献   

10.
OBJECTIVES: This study sought to compare the histologic grades of rejection in endomyocardial biopsy specimens with the global estimate of myocardial transplant-related cardiac damage detected by myocardial uptake of monoclonal antimyosin antibodies. BACKGROUND: The diagnosis and treatment of acute cardiac allograft rejection is based on the interpretation of endomyocardial biopsies. Because allograft rejection is a multifocal process and biopsy is obtained from a small area of the right ventricle, sampling error may occur. Global assessment of myocardial damage associated with graft rejection is now possible with the use of antimyosin scintigraphy. The present study was undertaken to compare the histologic grades of rejection in endomyocardial biopsy specimens with the global assessment of transplant-related myocardial damage detected by antimyosin scintigraphy. METHODS: Biopsies (n=395) from 112 patients were independently interpreted by three pathologists in a blinded manner according to the original Stanford four-grade (normal, mild, moderate and severe) and the current International Society of Heart and Lung Transplantation (ISHLT) seven-grade (0, 1A, 1B, 2, 3A, 3B and 4) classifications. The results were correlated with 395 antimyosin studies performed at the time of the biopsies. The heart/lung ratio of antimyosin antibody uptake was used to assess the severity of myocardial damage. RESULTS: In the Stanford biopsy grade classification, significantly higher antimyosin uptake, indicating increasing degrees of myocardial damage, were associated with normal (1.78+/-0.26), mild (1.88+/-0.31) and moderate (1.95+/-0.38) biopsy classifications for rejection (p < 0.01). In the ISHLT classification, significant differences were detected only for antimyosin uptake associated with grades 0 (1.77+/-0.26) and 3A (1.98+/-0.39) but not for intermediate scores (1A, 1B and 2). In view of the similar intensity of antibody uptake among the various grades, ISHLT biopsy scores were regrouped: normal biopsies in grade A; 1A and 1B as grade B; and 2 and 3A as grade C. Antimyosin uptake in grades A, B and C was 1.78+/-0.26, 1.88+/-0.31, 1.95+/-0.38, respectively (p < 0.01). CONCLUSIONS: The current ISHLT seven-grade scoring system does not reflect the progressive severity of myocardial damage associated with heart transplant rejection. Because myocardial damage constitutes the basis of treatment for allograft rejection, there is a need to reevaluate the ISHLT grading system, given its importance for multicenter trials.  相似文献   

11.
OBJECTIVES: The aim of this study was to assess 1) whether quantitative ultrasound tissue analysis by serial measurements of myocardial echo amplitudes can detect and monitor the onset and degree of acute cardiac rejection, as well as its resolution of acute rejection during treatment, and 2) whether changes in myocardial echo amplitudes are modified by repeat additional rejection episodes. BACKGROUND: Previous experimental studies, all involving heterotopic heart transplantation, have consistently shown reproducible alterations in myocardial echo amplitude during acute rejection episodes untreated by immunosuppressive agents. METHODS: Two-dimensional echocardiographic long-axis views were obtained daily under strict standardization in 12 dogs after heterotopic cervical heart transplantation (mean survival time 16.1 days) and digitized into a 256 x 256 x 8 matrix. Myocardial echo amplitudes were analyzed by gray level histogram statistics in regions of interest (45 x 12 pixels) within the proximal septum and posterior wall and correlated with the results of daily transmural myocardial biopsies. Maintenance immunosuppressive therapy consisted of cyclosporine, azathioprine and steroids. Additive steroids were given during acute cardiac rejection. RESULTS: All dogs experienced at least one moderate or severe episode of acute cardiac rejection. Successful resolution and repeat acute rejection were observed in three dogs. On 65 days, the left ventricular biopsy specimens showed no evidence of acute rejection. Mild acute rejection was present on 36, moderate on 29 and severe rejection on 40 days. End-diastolic mean (+/- SD) gray level increased progressively from 100.7 +/- 20.4 for no acute cardiac rejection to 113.8 +/- 23.1 for mild rejection (p = NS vs. no rejection) to 126.0 +/- 16.1 for moderate rejection (p < 0.01) and to 136.3 +/- 12.6 for severe rejection (p < 0.01). In each individual dog, a correlation between daily measurements of mean gray levels and histologic cardiac rejection grades was found (rmean = 0.80 +/- 0.14 [range 0.57 to 0.97], n = 12). In three dogs with transient complete histologic resolution of acute cardiac rejection, mean gray level did not return to values before rejection (108.0 +/- 15.4 vs. 87.2 +/- 8.4). The subsequent second episode of rejection was characterized by higher gray level values than those associated with the first rejection episode (141.3 +/- 14.4 vs. 124.3 +/- 20.9). CONCLUSIONS: Acute cardiac rejection is associated with a progressive increase in mean gray level. Changes in myocardial echo amplitudes in individuals may thus prove a useful tool for the noninvasive detection and monitoring of acute rejection. Increased mean gray level values after resolution of rejection may indicate persistent structural tissue abnormalities after rejection and demonstrate the need to define new baseline values after histologic resolution of an acute rejection episode.  相似文献   

12.
Acute cardiac graft rejection after transplantation, the diagnosis of which is based on the findings of endomyocardial biopsy, is associated with a reduction in coronary reserve due to abnormalities of the microcirculation. But this reduction in coronary reserve cause silent myocardial ischaemia (SMI)? In order to assess the frequency of SMI and ventricular arrhythmias during rejection, 53 consecutive Holter recordings were performed in 32 patients (28 men, 4 women, average age 47 +/- 11 years) 11 months after transplantation and within 24 hours of endomyocardial biopsy. The recorder which was used (Monitor One TC) analysed the ST segment in 2 leads in real time: ST segment depression of more than 1 mm lasting over 40 ms, 0.08 s after the J point were considered to be diagnostic of myocardial ischaemia. Although the frequency of SMI is low and not specific for cardiac rejection, its duration was twice as long (80 mn vs 38 mn) in this condition. On the other hand, ventricular arrhythmias are common in cardiac rejection and correlated with its severity according to Billingham's classification (VES p = 0.045; doublets p = 0.035; non-sustained VT p = 0.006).  相似文献   

13.
Six children with idiopathic restrictive cardiomyopathy were evaluated. Electrocardiographic evaluation disclosed left atrial dilatation and repolarization abnormalities. Echocardiographic examination showed gross left atrial enlargement (182 +/- 29% of predicted values, P < 0.001) in the presence of normal left ventricular cavity dimensions (99 +/- 6%, P: ns). Left ventricular wall thickness varied from normal to mild concentric hypertrophy (septum: 116 +/- 16%, P < 0.05). Global left ventricular systolic function was normal or slightly subnormal; however, the relaxation was significantly delayed throughout diastole. E/A ratio was 4.1 +/- 1.4 and deceleration time 94 +/- 7 ms. Marked ventricular filling occurred in mid-diastole as could be deduced from a prominent mid-diastolic mitral L wave on the Doppler flow tracing. Early filling contributed 56 +/- 6%, mid-diastolic filling 28 +/- 4% and atrial contraction 16 +/- 3% to total ventricular filling as estimated by determining E-area, L-area and A-area, respectively. The left ventricular pressure curve showed a steady decline during mid-diastolic filling. This implies that the driving force for mid-diastolic filling is not the increased left atrial pressure but suction by the ventricle. The restrictive haemodynamics are therefore not caused by increased intrinsic stiffness of the ventricular wall, but most likely result from serious dysfunction and delay of the active relaxation of the ventricle. Progression of the disease was observed in three out of six patients, resulting in death or extreme low cardiac output. The three other patients remained clinically stable during the follow-up period of 6-10 years.  相似文献   

14.
In congestive heart failure captopril modifies the left ventricular filling pattern mainly by unloading the heart. We investigated whether the structural characteristics of the left ventricle may influence the acute effects of captopril on this pattern in patients with untreated hypertensive (H group, 6 patients) or idiopathic (I group, 14 patients) cardiomyopathy. We evaluated changes of pulsed Doppler mitral flow, of systemic arterial and wedge pulmonary pressures 40 min after 25 mg captopril administered sublingually, and correlated these changes with the M-mode echocardiographic relative wall thickness index (h/r). Baseline mean arterial pressure (H = 137 +/- 20 mm Hg, mean +/- SD, I = 95 +/- 19 mm Hg; p < 0.001), and h/r (H = 0.38 +/- 0.03, I = 0.28 +/- 0.09; p < 0.05) were greater in the high blood pressure group; wedge pressure, echocardiographic biplane ejection fraction, and Doppler indexes of the left ventricular filling were similar in the two populations. After captopril, ejection fraction did not change significantly, mean arterial pressure decreased significantly in hypertensive patients (H group, baseline = 137 +/- 20, captopril = 119 +/- 10, p = 0.02; I group, baseline = 95 +/- 19, captopril = 90 +/- 24, p = nonsignificant), and the wedge pressure was reduced by the same extent in both groups (H group, baseline = 27.7 +/- 3, captopril = 21 +/- 7, p < 0.05; I group, baseline = 20 +/- 12, captopril = 15 +/- 8, p < 0.05). In the H group early mitral flow increased [(E wave integral) x (mitral annulus area)] by 38 +/- 15%, and was almost steady in the I group (-1.3 +/- 30%; group H vs. I = p < 0.01); late mitral flow [(A wave integral) x (mitral annulus area)] showed a pattern exactly opposite to this (H = +0.4 +/- 40%, I = +38 +/- 19; p < 0.01). In the whole population there was a significant correlation between the early/late flow ratio variations and baseline h/r (r = 0.6, p < 0.05). In chronic congestive heart failure, changes in left ventricular filling with captopril are related to h/r: a higher index, as recorded in the H group, is associated with "true normalization' of the filling pattern after captopril; a lower index, as recorded in the I group, is associated with "pseudonormalization' despite a similar decrease of left ventricular filling pressure.  相似文献   

15.
This study was designed to investigate whether the left ventricular filling profile during preceding control beats significantly affects the pulse deficit caused by ventricular premature contractions (VPCs). The study group consisted of 18 patients (10 men, eight women, 15-85 years old) who underwent electrophysiological catheterization because of sinus bradycardia. Using a temporary pacing lead inserted in the right ventricular apex, isolated VPCs with various coupling intervals were produced by electrical stimulation of the right ventricle. During the production of the VPCs, the mitral filling flow velocity using pulsed wave Doppler echocardiography, the femoral arterial pressure curve and the electrocardiogram were simultaneously recorded. The right ventricle was stimulated 800, 750, 700, 650, 600, 550, 500, 450 and 400 ms after the triggered control beat QRS complex. Pulse pressures during VPCs gradually decreased in relation to the shortening of the extrasystolic beat coupling interval. The longest coupling interval for each subject, which caused complete abolition of the pressure pulse during the VPC, was defined as the pulse deficit coupling interval. The early to late diastolic velocity-time integral ratio (Ei/Ai ratio) of the mitral filling flow velocity during the control beats which precede the VPC was obtained as an index expressing the left ventricular filling profile. The Ei/Ai ratio of the mitral filling flow velocity ranged from 0.7 to 4.5 (1.8 +/- 1.0). The pulse deficit coupling interval ranged from 440 to 640 ms (510 +/- 60 ms).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

16.
BACKGROUND: The true incidence and prognosis of myocarditis in children with acute dilated cardiomyopathy (DCM) at presentation remains uncertain. This study examines the incidence of lymphocytic myocarditis in a consecutive cohort of children with acute DCM at presentation and outcome after dual therapy immunosuppression with cyclosporine and steroids. METHODS: Twenty-nine consecutive children with acute DCM underwent early endomyocardial biopsy. Children with "definite" myocarditis comprised group I (n = 9) and were treated with cyclosporine and prednisolone. Group II (n = 2) had "borderline" myocarditis, and group III (n = 18) nonspecific histologic findings. Outcome was assessed by echocardiographic measurement of left ventricular end-diastolic dimension and fractional shortening, with follow-up endomyocardial biopsy in group I subjects. RESULTS: Myocardial inflammation with or without myocardial necrosis (groups I and II) was present in 38% of all cases. There were no initial clinical, electrocardiographic, or echocardiographic features to distinguish patients in group I from patients in group III. At presentation, the mean +/- SEM left ventricular end-diastolic dimension and fractional score-Z scores of group I patients were 4.6 +/- 1.7 and -5.1 +/- 0.8, respectively, compared with 0.8 +/- 0.3 and -0.9 +/- 0.4, respectively, at withdrawal of immunosuppression (p < 0.001 for both). Both of these parameters did not differ significantly from normal controls at least follow up. Two group I patients had a biopsy-proven relapse after withdrawal of therapy that responded to reinstitution of immunosuppression. At latest follow-up, all nine group I patients had regained normal left ventricular function compared with four of 18 group III patients (p < 0.001). CONCLUSION: Lymphocytic myocarditis is frequent in children with dilated cardiomyopathy and cannot be predicted from noninvasive investigations. The use of cyclosporine and steroids is associated with a favorable outcome, and a controlled trial of dual therapy immunosuppression in children is therefore warranted.  相似文献   

17.
OBJECTIVES: The aim of this study was to set up reference values for Doppler flow-derived left ventricular filling parameters and to evaluate physiologic determinants of changes in signal expression related to maturation. BACKGROUND: In left ventricular diastolic function studies, age-related modulations in signal expression are observed. Assuming degenerative myocardial changes to be absent during childhood and adolescence, the determinants of these modulations must be different from those suspected in adults. METHODS: Pulsed wave Doppler signals from the mitral valve tip region were recorded in 329 healthy subjects aged 2 months to 39 years. Multiple linear regression was used to evaluate statistical relations between Doppler flow signals and stroke volume in the mitral valve area. RESULTS: Increasing early filling time velocity integral throughout maturation caused a decrease in atrial filling fraction from 0.34+/-0.06 to 0.24+/-0.04 (p < 0.005). Peak flow velocities during atrial systole decreased from infancy to adolescence (66+/-15 to 41+/-10 cm/s). Main effects on signal modulation were caused by heart rate, stroke volume and mitral ring area with a linear model fit (R2) of 0.79 for early filling phase (E)-time velocity integral, 0.6 for atrial filling phase peak velocity 0.84 for total E duration and 0.73 for E deceleration time. Atrial filling phase-time velocity integral, albeit significantly dependent on heart rate, was stable throughout growth. CONCLUSIONS: During infancy and childhood, the stroke volume crossing the mitral valve is a main modulator for early filling phase (E)-time velocity integral and diastolic time intervals during early filling, whereas atrial filling phase parameters are mainly dependent on heart rate. This results in a more pronounced atrial filling during infancy and childhood.  相似文献   

18.
The aim of the study was to investigate the relationship between myocardial collagen and regional echo amplitude in humans with non-fibrotic myocardium. The ratio of myocardial collagen to total myocardial protein was determined as the hydroxyproline/leucine ratio in endomyocardial biopsies obtained from the right ventricular side of the interventricular septum in orthotopically transplanted hearts. Regional echo amplitude was measured in the interventricular septum. Patients were studied prospectively. Twenty-five patients (five female, 20 male) who had undergone orthotopic cardiac transplantation were studied 355 to 2939 days (1009 +/- 718, mean +/- SD) post-transplantation at the time of annual cardiac catheterization and endomyocardial biopsy. Patient ages varied from 22 to 62 years (46 +/- 11). Donor ages were 14 to 47 years (25 +/- 8) and the ischaemic time, 90 to 245 min (151 +/- 42). Cardiac transplantation was performed for end-stage cardiac failure in all patients. The aetiology of cardiac failure was valvular heart disease in three, dilated cardiomyopathy in eight and ischaemic heart disease in the remainder. Echo amplitude studies were performed within 24 h of endomyocardial biopsy. All but one patient were on an immunosuppressive regime consisting of cyclosporine A and azathioprine with additional steroids in three. The remaining patient, who was the longest surviving patient in the study group, had never been treated with cyclosporine. This patient was maintained on steroids and azathioprine alone. No patient had clinical or histological evidence for acute cardiac rejection and all were clinically well. Five patients had angiographic evidence of coronary artery disease. All subject studies were performed at Harefield Hospital.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

19.
Among 22 patients with isolated mitral regurgitation of various origins, systolic time intervals (preejection period [PEP] index, left ventricular ejection time [LVET] index and PEP/LVET) and echocardiographic measures of left ventricular performance (end-diastolic diameter [Dd], end-systolic diameter [Ds], and the percent change in minor axis diameter [% delta D]) were calculated. The patients were classified into two groups, those with a normal or supernormal % delta D (group I, 15 patients) and those with a decreased % delta D (group II, 7 patients). On group analysis, prolongation of the preejection period, shortening of the left ventricular ejection time and an increase in PEP/LVET was generally characteristic of patients with mitral regurgitation. These changes were accentuated when mitral regurgitation was complicated by echocardiographic evidence of diminished left ventricular contractile performance (% delta D less than 30 percent). An increase in PEP/LVET to greater than 0.05 was consistently associated with abnormal left ventricular performance, whereas a normal PEP/LVET ratio reflected normal or supernormal left ventricular performance. An inverse linear relation was found between PEP/LVET and % delta D. When compared with previous data on the relation of these variables among patients without valve insufficiency, PEP/LVET proved to be increased for any level of % delta D in mitral regurgitation. The state of digitalization did not appear to influence the relation between PEP/LVET and % delta D. The use of echocardiographic measurements augments the determination of systolic time intervals in the analysis of left ventricular performance in patients with mitral regurgitation.  相似文献   

20.
Transmitral Doppler flow patterns of patients with cardiac amyloidosis evolve from an early impaired relaxation to an advanced restrictive pattern. This reflects increasing severity of diastolic dysfunction and hence left ventricular filling pressures. The duration of the pulmonary venous atrial reversal flow was recently shown to exceed that of the mitral inflow A wave in patients with left ventricular end-diastolic pressure greater than 15 mm Hg. The objective of this study was to assess the utility of this index as a measure of the severity of cardiac amyloidosis. Comprehensive transthoracic 2-dimensional and pulsed-wave Doppler echocardiograms of the pulmonary venous and transmitral flows were made of 23 patients (10 women) with biopsy-proven diagnosis of primary systemic amyloidosis and of 49 subjects as age-matched normal controls. The amyloidosis group was divided into non-restrictive and restrictive subgroups on the basis of the patients' transmitral inflow deceleration time (>150 and < or =150 ms, respectively). The durations of the pulmonary venous atrial reversal and mitral inflow A wave were measured, and the differences between the flow durations were compared with the control and published data in the nonrestrictive and restrictive groups. The mean duration of the pulmonary venous atrial reversal was significantly longer in the amyloid than the control group (P < .01). The mean duration of the mitral inflow A wave was significantly shorter in the restrictive group than both the nonrestrictive and the control groups (P < .05). The duration of the pulmonary venous atrial reversal exceeded that of the mitral inflow A wave in all patients with cardiac amyloidosis. The difference in duration between pulmonary venous atrial reversal and mitral inflow A wave was significantly greater in the amyloidosis group compared with the normal group, and this index varied significantly within the amyloid group between the abnormal relaxation and the restrictive groups. The difference in the duration between the pulmonary venous atrial reversal and the mitral inflow A wave is a reliable index of diastolic function and can be used to assess the severity of cardiac amyloidosis.  相似文献   

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