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1.
BACKGROUND: The presence of mid-diastolic flow reversal on the mitral valve Doppler inflow indicates abnormal left ventricular filling. To determine whether mid-diastolic flow reversal predicts outcome in patients undergoing repair or palliation of neonatal congenital heart disease, we reviewed the echocardiograms and medical records of 40 patients with either left ventricular outflow obstruction or transposition of the great arteries. METHODS: All patients underwent surgical repair; transposition of the great arteries (TGA) = 17, coarctation of the aorta (CoA) = 14, interrupted aortic arch (IAA) = 8, and aortic stenosis (AS) = 1. The presence of mid-diastolic flow reversal was determined by pulsed Doppler interrogation of the mitral valve on preoperative and postoperative echocardiograms. RESULTS: Preoperative echocardiograms showed diastolic flow reversal in only 5 patients; 1 of 1 with AS and 4 of 14 with CoA. Twenty-one of 40 patients showed postoperative diastolic flow reversal; 1 of 1 with AS, 8 of 8 with IAA, 1 of 14 with CoA, and 11 of 17 with TGA. Postoperative mid-diastolic flow reversal 1 to 3 days after surgery was associated with higher mortality rate: 7 of 21 patients with diastolic flow reversal and 0 of 19 without diastolic flow reversal died. Patients with diastolic flow reversal who survived had longer intensive care unit (26.2 +/- 13.5 days vs 7.1 +/- 4.1 days, P <.001) and hospital (57.4 +/- 38.8 days vs 14.8 +/- 5.2 days, P <.05) stays. CONCLUSION: Mid-diastolic flow reversal is an indicator of prolonged hospital stay and mortality in patients with left ventricular outflow tract obstruction or TGA.  相似文献   

2.
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   

3.
Forty-nine patients with transposition of the great arteries who underwent a Mustard atrial baffle repair between 1964 and 1971 were assessed late postoperatively. There have been five late deaths: two related to baffle obstruction, two from noncardiac causes, and one sudden and unexpected. Hemodynamic data were available in 42 patients and autopsy in four. Obstruction of the lower venous channel was not encountered. Three patients had severe obstruction of the upper venous channel and in four there was mild restriction. Two patients had severe pulmonary venous obstruction resulting in late death; mild asymptomatic obstruction could not be excluded with certainty in six patients. Tricuspid incompetence was infrequently encountered in patients with an essentially intact ventricular septum. Left ventricular outflow tract obstruction was found in eight patients. In three it was present after satisfactory but incomplete surgical relief and in five it had not been recognized prior to operation. In only one of the latter patients was the obstruction important. Seventeen patients were operated on prior to one year of age. While baffle obstruction was confined almost entirely to these patients, the five youngest patients, aged one to nine weeks at operation, had adequate pulmonary and caval compartments at restudy two to three years later.  相似文献   

4.
Pulmonary blood flow distribution was studied by scintillation scanning of the lungs after the infusion of iodine- 131-labeled macroaggregates of human albumin before and after the Mustard operation in 53 patients with transposition of the great arteries. The patients were classified as follows: Group I (24 infants with uncomplicated transposition of the great arteries); Group II (18 patients with transposition and ventricular septal defect); and Group III (11 patients with transposition, ventricular septal defect and pulmonary obstruction). Before operation, 21 patients had a normal distribution of pulmonary blood flow, 10 had preferential flow to the right lung and 2 had preferential flow to the left lung. After operation, 19 had a normal pattern of pulmonary blood flow, 21 had preferential flow to the right lung and 3 had preferential flow to the left lung. The scanning studies have proved helpful in follow-up of patients to rule out recurrence of the shunt, pulmonary of systemic venous obstruction, development of pulmonary hypertension and occlusion of a palliative systemic-pulmonary shunt.  相似文献   

5.
Cardiac catheterization data from 54 investigations after Mustard's procedure were examined to study the influence of the operation on pressure events in the atria, great veins, and pulmonary circulation. Systemic venous atrial pressure tracings were characterized by a rapid, sharp 'y' descent. Pressure gradients between the venae cavae and systemic venous atrium were invariable, whether or not vena caval pathway obstruction was present, the 'y' trough and 'a' wave gradients being greater than the mean gradient. Pulmonary venous atrial pressure tracings were not different from normal except when tricuspid regurgitation was present. It is suggested that the baffle effectively reduces the size and compliance of the systemic venous atrium, but influences the pulmonary venous atrium to a lesser degree. The systolic pressure gradient from the left ventricle to pulmonary artery was decreased postoperatively, suggesting that it may be flow-related; the greatest changes were seen in the group with preoperative ventricular septal defect. The ratio of pulmonary: systemic vascular resistance did not change significantly after operation, and it is suggested that both the pre- and postoperative values were higher than normal. Examination of the left ventricular or pulmonary arterial mean pressure postoperatively should raise the suspicion of a complication, e.g. pulmonary venous obstruction or tricuspid regurgitation.  相似文献   

6.
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   

7.
Transposition of the great arteries is functionally corrected by Mustard's operation, an operation in which the atrial septum is removed and the resulting common atrial chamber repartitioned by a baffle to transpose venous return to the heart. To better understand the new physiology, a physically-based mathematical model of the infant circulation following Mustard's operation was developed and studied with the aid of computer simulation. The model reproduces certain clinical observations, including the tendency for mean pressure in both atria to be equal early postoperatively and for the pressure waveform to exhibit a steep y-descent in the systemic venous atrium. Simulation studies suggest that the mechanism for the former is transbaffle pressure coupling resulting from dynamic motion of the baffle; the mechanism for the latter is limitation of the extent of such baffle excursions. Dynamic volume of the two atria is found in the model to change according to the relative performance of the two ventricles, and stiffening the baffle leads to pressure waveforms characteristic of a small, noncompliant atrium. Mechanisms for venous "obstruction" and decompression were also studied. The baffle and its movements, however, have little effect upon cardiac output in the model, leaving unexplained the clinical observation of low output early postoperatively.  相似文献   

8.
BACKGROUND: In the repair of total anomalous venous connection, vertical vein ligation is recommended to eliminate left-to-right shunting. However, the small left heart chambers may not always tolerate the immediate increase in blood flow after combined repair and vein ligation. METHODS: A retrospective review of 23 infants and children undergoing correction of total anomalous pulmonary venous connection was undertaken to determine whether vertical vein ligation is a necessary component of successful surgical repair. In 14 patients this vein was ligated, whereas in 9 it was left patent. Six patients who underwent ligation and 5 who did not had pulmonary venous obstruction before operation. RESULTS: The operative mortality rate was 36% (5 of 14 patients) for the ligated group compared with 0% (0 of 9 patients) for the nonligated group (p = 0.06). All deaths occurred in patients with preoperative obstruction and a low mean left atrial pressure, and four of the deaths were directly attributable to left heart failure. Follow-up echocardiography in patients in whom the vertical vein was not ligated revealed adequate cardiac function and no residual left-to-right flow through the previously patent venous conduit. CONCLUSION: Vertical vein ligation during the repair of total anomalous pulmonary venous connection is not routinely necessary and actually may be undesirable in patients with preoperative obstruction, in whom the left heart chambers are particularly small.  相似文献   

9.
Juxtaposition of the atrial appendages is an uncommon anomaly which is usually associated with transposition of the great arteries. Experience with five patients with transposition of the great arteries in combination with juxtaposition of the atrial appendages in whom Mustard's operation was performed is reviewed. Technically, the existence of juxtaposition of the atrial appendages in corrective surgery for transposition does not present any additional surgical problems. Emphasis is placed on the advantages of early complete correction, avoiding the need for palliative procedure.  相似文献   

10.
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   

11.
Orthotopic heart transplantation results in altered atrial anatomy and denervation of the donor heart. To assess the impact of these sequelae on left ventricular filling and systolic performance, 16 heart transplant recipients and 10 normal controls were evaluated by Doppler echocardiography at rest and during graded bicycle exercise. Global and regional systolic ventricular allograft function was normal at rest and during exercise. Resting Doppler profiles demonstrated diminished atrial contribution to ventricular filling in transplant recipients. The response to dynamic exercise was different in both groups; controls increased heart rate, while mitral time-velocity integral was unchanged. Heart transplant recipients, in contrast, showed a blunted heart rate response and increased time-velocity integral. Atrial contribution to ventricular filling was not augmented during exercise as in normal controls. Alterations in transmitral flow profiles in heart transplant recipients do not necessarily reflect ventricular myocardial damage, but may be related to impaired atrial function.  相似文献   

12.
Previous studies showed that difference in pulmonary venous and mitral A-wave durations can be used for the estimation of left ventricular end-diastolic pressure, which is based on the assumption that the pulmonary venous A wave and mitral A wave start with the beginning of left atrial contraction. It is also assumed that the mitral A wave ends with the end of left atrial contraction. These assumptions may not be correct if left atrial contraction occurs before the early left ventricular filling is completed. Adequate Doppler mitral inflow and pulmonary venous flow signals were obtained simultaneously with left ventricular pressures at the cardiac catheterization laboratory in 50 patients who showed separated E and A waves in mitral inflow. After heart rate was increased by right atrial pacing to make the mitral E and A waves overlap, Doppler and hemodynamic measurements were repeated. When E and A waves are separated, pulmonary A-wave duration exceeding mitral A-wave duration has a sensitivity of 67% and specificity of 85% in the prediction of elevated left ventricular end-diastolic pressure (>/=20 mm Hg), whereas the pulmonary A wave ending later than mitral A wave has a sensitivity of 83% and a specificity of 45%. When the mitral E and A waves are overlapped, the pulmonary A wave ending later than mitral A wave is better for the prediction of elevated left ventricular end-diastolic pressure (sensitivity 55%, specificity 75%) than pulmonary A-wave duration exceeding mitral A-wave duration (sensitivity 9%, specificity 96%). However, overall, both methods are limited for clinical use.  相似文献   

13.
Left-sided juxtaposition of the right atrial appendage (LJRAA) was seen in 10 patients in a series of 361 consecutive Mustard procedures for transposition of the great arteries (TGA). Dextrocardia complicated LJRAA in four cases. Right atrial capacity and free atrial wall size were smaller than normal in all patients, and a Mustard intra-atrial baffle repair was performed in all instances. Direct caval cannulation or cannulation of either atrial appendage facilitated intra-atrial repair. Nine patients in whom the pulmonary venous atrium was enlarged with a patch survived. One child who did not have a right atrial patch died 1 hour postoperatively of pulmonary edema. Two late deaths occurred 1 year postoperatively. Seven children survived and are well. In one child, superior vena caval baffle obstruction is controlled by digoxin and diuretic therapy. TGA associated with juxtaposition of the atrial appendages (JAA) and dextrocardia may be successfully repaired by the Mustard procedure, provided that the tricuspid valve and right ventricle are normal, an adequate superior vena caval channel is created, and patch enlargement of the pulmonary venous atrium is undertaken.  相似文献   

14.
The clinical, hemodynamic, and angiographic observations, as well as the surgical approach used for repair in three patients with congenitally corrected transposition of the great arteries and ventricular membranous septal aneurysms, are presented. In two of the three patients the membranous septal aneurysm caused subpulmonary obstruction, with 94 and 125 mm Hg systolic gradients. In each patient the aneurysm was demonstrated by angiocardiography, which also showed differences in size and shape with cardiac systole and diastole. Review of the previously described reports indicates that patients with congenitally corrected transposition often display various forms of pulmonary outflow obstruction and when a ventricular membranous septal aneurysm exists, a significant subpulmonary obstruction is present in most patients. The unique anatomic relationship between the pulmonary artery and a ventricular membranous septal aneurysm in patients with transposition of the great arteries with and without atrioventricular discordance explains why subpulmonary obstruction sometimes develops.  相似文献   

15.
BACKGROUND: Congenitally corrected transposition of the great arteries is a complex cardiac lesion, usually associated with ventricular septal defect, left ventricular outflow tract obstruction, and tricuspid valve abnormalities. A subset of patients without left ventricular outflow tract obstruction have undergone Senning plus arterial switch operation in an attempt to place the left ventricle in the systemic circuit and the right ventricle in the pulmonary circuit. METHODS: Fourteen patients have had the operation performed since July 1989. Age and weight medians were 12 months (range, 0.5 to 120 months) and 8.2 kg (range, 3.2 to 34 kg). All but 1 patient had a left ventricular to right ventricular pressure ratio greater than 0.7, due to a large ventricular septal defect (with or without a previous pulmonary artery band), severe congestive heart failure caused by right ventricular dysfunction and tricuspid insufficiency, or a pulmonary artery band for left ventricular retraining. At least 10 patients had strong contraindications to "classic" repair, including right ventricular hypoplasia (n = 2), moderate to severe right ventricular dysfunction (n = 5), or moderate to severe tricuspid insufficiency (n = 9). RESULTS: There was one hospital death, occurring in a neonate (7%; 95% confidence interval = 0% to 34%). Actuarial survival beyond 10 months is 81% (95% confidence interval = 42% to 95%), currently with 389 patient-months of total follow-up time. The median grade of tricuspid insufficiency fell from 3/4 preoperatively to 1/4 postoperatively (p = 0.003). Right ventricular function is normal in 11/12 current survivors, all but 1 of whom are in New York Heart Association class I or II. CONCLUSIONS: Senning plus arterial switch operation is a good option for selected patients with congenitally corrected transposition of the great arteries with a similar or lower early risk (as compared with classic repairs). Some of the long-term problems associated with congenitally corrected transposition of the great arteries may be avoided with this strategy.  相似文献   

16.
Late systemic venous baffle obstruction after Mustard repair for complete transposition of the great arteries is a recognized complication. Balloon-expandable intravascular stents have previously been used to relieve systemic baffle narrowing in children. We report a successful stent implantation to relieve symptomatic superior vena cava obstruction and baffle dehiscence after Mustard repair in an adult patient. She had been turned down for surgery due to right ventricular dysfunction. Eighteen months after the procedure, she remains symptomless.  相似文献   

17.
Abnormalities of diastolic filling are increasingly recognized as a cause of symptoms and predictors of outcome in patients with most forms of heart disease. Noninvasive assessment of diastolic filling is possible in almost all patients, but accurate evaluation must relate echocardiographic Doppler measurements to the complex physiologic and hemodynamic factors responsible for normal and abnormal filling. This evaluation has been facilitated by recent correlation of Doppler measurement of mitral and pulmonary venous inflow with hemodynamic studies. These studies have confirmed that when a careful, integrated approach is taken, Doppler flow patterns can document a progressive pattern of abnormality in many conditions. Impaired left ventricular (LV) relaxation is seen early and is recognized by a decrease in early transmitral LV filling and an increased proportion of filling during atrial contraction. As abnormalities progress, increasing LV chamber stiffness and elevated left atrial pressure lead to a "pseudonormal" filling pattern that previously has caused considerable confusion. This can be unmasked by careful evaluation of pulmonary venous inflow and the use of the Valsalva maneuver. When marked diastolic abnormalities are present, LV filling has restrictive features characterized by rapid early filling, a very stiff left ventricle with high filling pressures, and a poor prognosis. Routine measurement of indexes of diastolic filling have been hampered by uncertainty as to what should be measured, what techniques should be used, definition of normal values, and a clear method of reporting findings. This report represents the efforts of a Canadian consensus group to define a national standard for the performance and reporting of echocardiographic Doppler studies of diastolic filling.  相似文献   

18.
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   

19.
Cardiac performance was evaluated in 12 infants with isolated total anomalous pulmonary venous return. Four had significant pulmonary venous obstruction and severe pulmonary hypertension (group A). Eight had no obvious venous obstruction, and the pulmonary pressures were lower (group B). In all subjects, right ventricular end-diastolic volume was increased (197% of predicted normal) and its ejection fraction was normal. Left ventricular volume was, generally speaking, still in the normal range (87% of predicted normal); however, its ejection fraction was reduced (0.57 vs normal of 0.73) and left ventricular output was low (3.08 L/min/m2 vs normal of 3.98). Left atrial volume was consistently small (53% of predicted normal) with an appendage of normal size. The infants in group A had smaller chamber volumes/m2 BSA than those in group B. Left atrial function was abnormal, characterized by reduced reservoir function and a greater role as "conduit" from right atrium to left ventricle. Left atrial size was not found to be critical in the surgical repair of TAPVR. Cardiac function is restored to normal following surgery.  相似文献   

20.
AIMS: To assess outcomes of anatomical repair (double switch procedure) in infants and children with congenitally corrected transposition of the great arteries. METHODS AND RESULTS: Between September 1993 and August 1996, 17 patients with congenitally corrected transposition underwent surgery at UCSF. Anatomical repair was performed in 11 of these patients, at ages ranging from 4.8 months to 7.8 years (median 3.2 years). The remaining six patients did not undergo anatomical repair due to unfavourable anatomy (n = 2), prior conduit repair (n = 2), biventricular dysfunction (n = 1), and isolated complete atrioventricular block (n = 1). The 11 patients who underwent anatomical repair make up the study group for the present report. All 11 patients had a malalignment ventricular septal defect, while pulmonary outflow tract obstruction was present in nine patients and significant tricuspid valve pathology or dysfunction was present in five. Anatomical repair was achieved with a Senning (n = 7) or a Mustard (n = 4) procedure combined with an arterial switch operation plus ventricular septal defect closure (n = 4), or a Rastelli procedure with left ventricle to aortic baffle and right ventricle to pulmonary artery conduit (n = 7). There was one early death and no patients developed surgical complete atrioventricular block. At a median follow-up of 22 months, there were no late deaths. Two patients required a total of three late reoperations, and all patients were asymptomatic on no cardiac medication. Follow-up echocardiography revealed normal biventricular function in all patients. CONCLUSIONS: Anatomical repair of corrected transposition can be achieved with low rates of early mortality and surgical heart block, and favourable mid-term results. Long-term follow-up will be necessary to determine if the double switch approach improves the natural history of corrected transposition when compared to less aggressive surgical approaches that leave the right ventricle in the systemic circulation.  相似文献   

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