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1.
BACKGROUND: In most cases of transposition of the great arteries with ventricular septal defect and left ventricular outflow tract obstruction, a Lecompte procedure (réparation à l'étage ventriculaire) is possible without interposition of a conduit between the right ventricle and pulmonary artery. However, the anterior location of the pulmonary arteries after the Lecompte maneuver may be a potential cause for right ventricular outflow obstruction, which continues to be reported in 5% to 25% of cases. We have used a tubular segment of aortic autograft to connect the pulmonary artery, left in the orthotopic posterior position (without the Lecompte maneuver), to the right ventricle in 10 consecutive patients with transposition, ventricular septal defect, and left ventricular outflow tract obstruction. METHODS: Ten consecutive patients aged 2 months to 11 years (mean 32 months) have undergone a modified Lecompte operation. Eight had severe pulmonary stenosis, two had pulmonary atresia, and four had a restrictive ventricular septal defect at the time of the operation. Two had multiple ventricular septal defects. Seven had undergone one (n = 5) or two (n = 2) previous modified Blalock-Taussig shunts. All patients underwent a total correction with left ventricular-aortic intraventricular connection (four needed a ventricular septal defect enlargement), connection between the right ventricle and pulmonary arteries with a tubular segment of autograft aorta, without the Lecompte maneuver (anterior location of the bifurcation of the pulmonary arteries) on the right (n = 6) or the left (n = 4) of the aorta. No valvular device was used for the right ventricular outflow repair. RESULTS: No early or late deaths occurred. One patient with multiple ventricular septal defects needed an early (2 weeks) reoperation for a residual muscular ventricular septal defect. All patients are currently in New York Heart. Association class I, without medications, in sinus rhythm, at a mean follow-up of 30 months. Late results up to 3.6 years show no calcification on the chest roentgenogram, and at the most recent echocardiogram, right ventricular pressures were low (25 to 40 mm Hg, mean 33 mm Hg) and no significant gradient (over 10 mm Hg) was found between the right ventricle and pulmonary arteries. Left and right ventricular function was satisfactory. CONCLUSION: This modification of the Lecompte operation using a segment of autograft allows an excellent early and late result, with no danger of compression of anteriorly placed pulmonary arteries, no significant right ventricular outflow obstruction, and normal appearance of the tubular autograft. In view of laboratory and clinical evidence, normal growth of the autograft can be anticipated. It allows an elective correction of transposition, ventricular septal defect, and left ventricular outflow tract obstruction without a previous Blalock-Taussig shunt (three patients) and correction at a young age (three patients younger than 1 year).  相似文献   

2.
We present a 74-year-old female who showed a large left-to-right shunt through a small atrial septal defect presumably due to diastolic dysfunction of the left ventricle caused by the progression of aortic stenosis. Accordingly, elderly patients with even small atrial septal defect should be followed carefully, since diastolic dysfunction of the acquired left ventricular disorder could increase the left-to-right shunt.  相似文献   

3.
To define the clinical course of ventricular septal defect, 410 consecutive patients with isolated ventricular septal defect were evaluated over a period of 13 years. Their age ranged from 12 days to 24 years at the time of first visit to the hospital. Patients with less than 2 years follow-up period were excluded. One hundred and fifty seven patients were one year of age or less. The left to right shunt size remained the same in 52.4% of cases. In 34.4% the shunt size decreased, with complete closure of ventricular septal defect in 8.8%. Closure of ventricular septal defect was observed even in patients who had initially presented with large left to right flow, and congestive heart failure in infancy. Right ventricular outflow tract obstruction developed in 8.5% of patients usually between 2 and 10 years of age. Murmur of aortic regurgitation appeared in 8.9% on follow-up. Infective endocarditis developed in 6 cases. The unfortunate complication of Eisemenger's complex was seen in 3 patients; they had not returned for follow up for a long period of time. Hence, our data show that the left to right shunt across the ventricular septal defect decreases in about one-third of patients. However, a regular follow up is essential to prevent development of Eisenmenger's complex and for early detection of other complications like aortic regurgitation and right ventricular outflow tract obstruction.  相似文献   

4.
Adult myocardium adapts to changing functional demands by hyper- or hypotrophy while the developing heart reacts by hyper- or hypoplasia. How embryonic myocardial architecture adjusts to experimentally altered loading is not known. We subjected the chick embryonic hearts to mechanically altered loading to study its influence upon ventricular myoarchitecture. Chick embryonic hearts were subjected to conotruncal banding (increased afterload model), or left atrial ligation or clipping, creating a combined model of increased preload in right ventricle and decreased preload in left ventricle. Modifications of myocardial architecture were studied by scanning electron microscopy and histology with morphometry. In the conotruncal banded group, there was a mild to moderate ventricular dilatation, thickening of the compact myocardium and trabeculae, and spiraling of trabecular course in the left ventricle. Right atrioventricular valve morphology was altered from normal muscular flap towards a bicuspid structure. Left atrial ligation or clipping resulted in hypoplasia of the left heart structures with compensatory overdevelopment on the right side. Hypoplastic left ventricle had decreased myocardial volume and showed accelerated trabecular compaction. Increased volume load in the right ventricle was compensated primarily by chamber dilatation with altered trabecular pattern, and by trabecular proliferation and thickening of the compact myocardium at the later stages. A ventricular septal defect was noted in all conotruncal banded, and 25% of left atrial ligated hearts. Increasing pressure load is a main stimulus for embryonic myocardial growth, while increased volume load is compensated primarily by dilatation. Adequate loading is important for normal cardiac morphogenesis and the development of typical myocardial patterns.  相似文献   

5.
The aim of the present study was to investigate the pattern of ventricular dynamic contraction and its relation to changes of transseptal pressure gradient during ventilation with positive end-expiratory pressure (PEEP). For that purpose, left (LV) and right ventricular (RV) pressures as well as ventricular shortening in septal-lateral (s.l.) direction were assessed in 8 dogs (RV n = 5) exposed to experimental acute respiratory distress syndrome (eARDS) and PEEP 10 and 20 cmH2O (P10, P20). Despite maintenance of transmural central venous pressure by volume substitution, PEEP resulted in a fall of stroke index (P10 vs. eARDS: -7%, p<0.05; P20 vs. P10: -28%, p<0.05); this was accompanied by a fall of LV end-diastolic diameter (P10 vs. eARDS: -3.1%, p<0.01; P20 vs. P10: -7.4%, p<0.01). Although the transseptal LV to RV end- diastolic pressure gradient changed only minimally, there was a significant increase of paradoxic left ventricular systolic lengthening from 3.1% at eARDS to 4.5% at P10 (p<0.05 vs. eARDS) and 8.4% at P20 (p<0.05 vs. P10). Neither RV end-diastolic diameter nor s.l. shortening were significantly influenced by P10 or P20. It is concluded, that a rearrangement of LV dynamic contraction does occur during ventilation with PEEP, which is compatible with the concept of paradoxic systolic bulging of the interventricular septum towards the lumen of the right ventricle. Since this phenomenon occurred independent from changes of the end-diastolic pressure gradient between both ventricles, we suggest that systolic septal movement to the right is an active contractile process to support the function of a stressed RV.  相似文献   

6.
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   

7.
The ratio of pulmonary to systemic vascular resistance (Rp/Rs) largely determines the amount of left-to-right shunting and pulmonary to systemic flow rat (Qp/Qs) in the presence of a large isolated ventricular septal defect. The possibility that pharmacologic reduction of systemic vascular resistance with alpha-adrenergic receptor blockade or beta-adrenergic receptor stimulation would increase the ratio Rp/Rs, and therefore reduce the ratio Qp/Qs, was studied in dogs in which ventricular septal defects had been surgically created. Administration of phentolamine and phenoxybenzamine caused a 42% reduction in Rs and no reduction in Rp. Qs was unchanged and Qp declined by 24% and the ratio Qp/Qs fell by 32%. Infusion of the beta-adrenergic receptor stimulant isoproterenol also reduced Qp/Qs. However, this was accomplished as a result of an increase in Qs and at the expense of an increase in heart rate. As a decline in the ratio Qp/Qs has been shown to be beneficial to patients with large left-to-right shunts, pharmacologic reduction of systemic vascular resistance may prove to be helpful in treating congestive heart failure in those patients with large left-to-right shunts at the ventricular level who are refractory to the usual decongestive measures.  相似文献   

8.
Cross-sectional echocardiography, combined with injections of contrast into peripheral arm veins, has been used to study 15 patients with atrial septal defects and 10 patients with an intact interatrial septum. Of 11 patients with ostium secundum or sinus venosus atrial septal defects and left-to-right shunts a defect could be visualised in all, and in eight some degree of transfer of contrast from right atrium to left atrium was seen. In three of four patients with a dominant right-to-left shunt a defect was seen and in all there was free transfer of contrast from right atrium to left atrium. Though there may be variable loss of echoes in the septal image in patients with an intact interatrial septum, in general no fixed defect is seen an there is no transfer of contrast from right atrium to left atrium. This is a potentially valuable technique in the assessment of patients in whom an atrial septal defect is suspected.  相似文献   

9.
Seven patients with pulmonary regurgitation (PR), normal pulmonary artery (PA) pressures and large left-to-right atrial shunts are reported. Six had secundum atrial septal defects (ASD) and one had anomalous pulmonary venous drainage. These comprised 4% of 180 patients with atrial shunts and normal PA pressures. Pulmonary regurgitation was diagnosed clinically by mid-frequency diastolic decrescendo murmurs beginning after the pulmonic component of the second heart sound, and diagnoses were confirmed by catheterization. In two patients who had serial preoperative catheterizations over 8 and 16 years, PR progressed in one and was present only on the second study in the other. All patients underwent shunt correction, at which time the pulmonic anulus and artery appeared dilated, but the pulmonic valves were normal and did not require revision. In all patients the PR murmur disappeared after shunt correction alone, and on chest X-ray both PA and overall heart size decreased. Although it is known that pulmonary regurgitation occurs with atrial septal defects and pulmonary hypertension, the present study demonstrates that it also occurs with high flow atrial shunts, in which setting it has different implications and is reversible with shunt correction alone.  相似文献   

10.
Diastolic function of the left ventricle was analysed in patients with different cardiac diseases: acute and chronic volume overload (in aortic and mitral incompetence), pressure overload and inappropriate ventricular hypertrophy (aortic stenosis and hypertrophic cardiomyopathy), congestive cardiomyopathy, and constrictive pericarditis. Most patients were receiving digitalis therapy at the time of study. A constant exponential relation between pressure and volume was assumed, and pressure-volume curves were constructed from two points: the instantaneous pressure-volume relation at beginning-diastole and at end-diastole. The determinants of left ventricular end-diastolic pressure were studied. Left ventricular end-diastolic pressure depended on the beginning-diastolic pressure and volume (O point), the slope of the pressure-volume curve (m), and the volume which distended the ventricle in diastole. In chronic volume loading and in congestive cardiomyopathy the curves were flatter than normal, so that left ventricular end-diastolic pressure was only slightly increased despite the large volume filling the ventricle. In pressure overload and in constrictive pericarditis the curves were steeper than normal. Acute changes in volume were accomplished by a shift up or down the pressure-volume curve but in these patients the slope was not altered: the ventricle had not had time to adapt and end-diastolic pressure was greatly increased.  相似文献   

11.
Radiofrequency transcatheter ablation of ventricular tachycardia in the setting of a prior myocardial infarction is typically performed with application of energy to the left ventricular endocardium. In this article, two cases are described in which successful radiofrequency transcatheter ablation of ventricular tachycardia occurred with energy delivery to the right ventricular septum after failed ablation attempts from the left ventricle. Both patients had tachycardias with a left bundle branch block morphology and markedly presystolic activity recorded from the right ventricular septum. Right ventricular septal activation mapping during ventricular tachycardia should be performed in patients with left bundle branch block tachycardia morphology and coronary artery disease to maximize efficacy of the catheter ablation procedure.  相似文献   

12.
BACKGROUND: Although cardiomyoplasty (CMP) is thought to improve ventricular systolic function, its effects on ventricular diastolic function are not clear. Especially the effects on right ventricular diastolic filling have not been fully investigated. Because pericardial influences are more pronounced in the right ventricle than in the left ventricle, CMP with its external constraint may substantially impair right ventricular diastolic filling. METHODS: Fourteen purebred adult beagles were used in this study. Seven underwent left posterior CMP, and 7 underwent a sham operation with a pericardiotomy and served as controls. Four weeks later, the hemodynamic effects of CMP were evaluated by heart catheterization before and after volume loading (central venous infusion of 10 mg/kg of 4.5% albumin solution for 5 minutes). RESULTS: In the CMP group, mean right atrial pressure and right ventricular end-diastolic pressure increased significantly from 3.1 +/- 1.2 mm Hg to 6.1 +/- 2.0 mm Hg (p < 0.001) and from 4.0 +/- 1.8 mm Hg to 9.6 +/- 2.5 mm Hg (p < 0.001), respectively. Volume loading in the control group did not significantly increase either variable. Right ventricular end-diastolic volume and stroke volume did not change significantly (from 53 +/- 9.3 mL to 60 +/- 9.0 mL and from 20 +/- 2.3 mL to 21 +/- 3.2 mL, respectively) in the CMP group. In the control group, however, right ventricular end-diastolic volume and stroke volume increased significantly from 45 +/- 7.7 mL to 63 +/- 14 mL (p < 0.05) and from 18 +/- 4.3 mL to 22 +/- 4.2 mL (p < 0.05), respectively. CONCLUSIONS: These results suggest that CMP may reduce right ventricular compliance and restrict right ventricular diastolic filling in response to rapid volume loading because of its external constraint.  相似文献   

13.
The accuracy of echocardiographic estimation of left-to-right shunts was studied prospectively in children with secundum ASD. Fifty-one consecutive patients were examined from March 1987 to August 1991. Mean age was 64/12 years with a minimum age of 12/12 and a maximum of 131/12 years. Twenty-five children were included in the first part of the study. The ratios of right and left atrial and ventricular areas and pulmonary and aortic diameters were correlated with the left-to-right shunts determined by oximetry (mean shunt 48.7%; min. 10.1%, max. 73.2%). The pulmonary/aortic diameter ratio provided the closest correlation (r = 0.95; p < 0.01). During the second part of the study the left-to-right shunt was estimated using the regression equations developed from part one. Thus, in 26 subsequent patients these values were compared with oximetric shunt values. Again, the pulmonary/aortic diameter ratio provided the closest correlation (r = 0.97). The pair comparison yielded a difference of 0.7 +/- 3.8%. Based on these results since 1991, surgery for ASD II has been performed without preoperative cardiac catheterization in 33 patients, provided echocardiographic shunt estimation was > or = 48%.  相似文献   

14.
The echocardiographic abnormalities of tricuspid valve motion in 2 patients with left ventricular to right atrial shunts are described. In both patients the abnormal anatomy was defined at surgery, in one patient the shunt being above the tricuspid valve leaflets (supravalvar) and in the other patient through the septal leaflet (intravalvar). Different patterns of tricuspid valve systolic fluttering were seen in these two cases and the possible reasons for this are discussed. After surgical closure of the defects the systolic fluttering of the tricuspid valve was no longer observed. Echocardiography appears to be useful in detecting the presence of left ventricular to right atrial shunts which otherwise may be difficult to diagnose.  相似文献   

15.
Hemodynamic data in 43 patients with right and left ventricular infarction and 39 with left ventricular infarction were compared. Right atrial pressure, pulmonary capillary wedge pressure, mean pulmonary artery pressure, left ventricular end-diastolic pressure before and after ventricular angiogram, cardiac index, left ventricular stroke volume index, right ventricular stroke work index were evaluated, as well as ratios of right atrial and pulmonary capillary wedge pressure, right and left ventricular end-diastolic pressure, right ventricular end-diastolic and pulmonary capillary wedge pressure, left ventricular ejection fraction calculated from left ventricular angiogram, Berentey's score, and cardiac volume index. Using ONEWAY analysis there was no significant difference between the two groups in period of rehabilitation. In 15 patients with right ventricular infarction regression of ECG changes was observed in lead V3R also without significant influence on hemodynamic data.  相似文献   

16.
Pulsed Doppler echocardiographic and hemodynamic examinations were performed in 31 patients (mean age 17.8 years) with isolated ventricular septal defect (VSD). Three groups were studied: group I (n = 6) patients had severe pulmonary vascular obstructive disease (PVOD); group II (n = 12) patients had pulmonary hypertension (PH) without severe PVOD; group III (n = 13) patients had no PH. Bidirectional shunting was detected in 9 VSD patients (6 in group I and 3 in group II). Patients with low to moderately elevated right ventricular pressures demonstrated left-to-right shunting across the defect throughout the cardiac cycle. When systolic pressure in the right ventricle reached approximately 60% of the left ventricular pressure, right-to-left shunting occurred across the defect during early and mid diastole. However, in patients with Eisenmenger syndrome (group I) the right-to-left shunting occurred during late systole with continuation during the early and mid diastolic period. The earlier occurrence of right-to-left shunting (index < 0.5 second) signifies the presence of severe PVOD.  相似文献   

17.
BACKGROUND: Right ventricular (RV) function and morphometric quantitation of interstitial fibrosis in idiopathic dilated cardiomyopathy (IDC) have not been the subject of specifically designed clinical observations. In particular, their role in routine assessment and prognostic evaluation of patients (pts) with IDC remains to be settled. METHODS: Eighty-one consecutive IDC patients (63 M, 18 F; mean age 52 +/- 11 yrs) with left ventricular (LV) systolic dysfunction (angiographic ejection fraction - EF - < 55%), normal coronary arteries and no histologic evidence of myocarditis were studied. Cardiac catheterization and endomyocardial biopsy (EMB) were routinely performed in all cases. RV volumes and EF were obtained by angiography according to Ferlinz' method and interstitial fibrosis was quantitated by computer-assisted morphometric analysis. These data were analyzed in order to study correlations with hemodynamic parameters and to assess their prognostic value in a long-term follow-up. RESULTS: In the study population, right ventricular EF was significantly lower than in normal controls (35 +/- 11% vs 53 +/- 6%, p < 0.0001) and showed a significant positive correlation with LV EF (r = 0.54; p < 0.0001), and a weak but significant negative correlation with fibrosis (r = -0.29; p = 0.03). RV volumes, but not EF, were significantly related to mean pulmonary pressure. At multivariate analysis, RV end-diastolic volume (EDV) and EF were the two independent predictors of severe heart failure (NYHA class III-IV). After a mean follow-up of 64 +/- 36 months, 20 pts died and 9 had heart transplantation, for a 63% transplant-free survival rate (TFS). Multivariate analysis identified three independent predictors of TFS: LV stroke work index (p < 0.0001), RV stroke work index (p = 0.02) and RV EDV (p = 0.03). Fibrosis was predictive of survival only in the subgroup with LV EF < 20%. CONCLUSIONS: Assessment of RV function provides useful information in the evaluation of hemodynamic profile and prognosis of pts with IDC. Quantitation of interstitial fibrosis by morphometry provides little additional data.  相似文献   

18.
Atrial septal defect (ASD) is one of the most common congenital cardiac anomalies encountered in adulthood. The evaluation of the pulmonary hypertension in ASD is clinically important for operative indication and prognosis. The pulmonary vasculature in chest radiographs in patients with ASD is characterized as dilatation of the central pulmonary arteries and increase of the peripheral pulmonary vessels in patients without pulmonary arterial hypertension (PH) and constriction of the peripheral pulmonary arteries in those with pulmonary hypertension. While the dilatation of the main pulmonary artery occurs in the patients both with and without pulmonary hypertension, its precise radiographic evaluation with regard to the morphological and hemodynamic change of the right ventricle and pulmonary arteries has not been reported. This study was to determine if the contour of the main pulmonary artery segment of the cardiac silhouette in the conventional frontal chest radiograph could be used 1) as indicators of PH or raised right ventricular pressure and 2) as a reliable base for evaluation of the size of the right ventricule (RV) in ASD. The intersection of the line (line A) drawn tangentially to the lateral lower margin of the main pulmonary artery segment to the horizontal line at the left hemidiaphragm is closely related to the apex of RV as measured by right ventricular angiography in supine position. The ratios of the distance of the intersection from the midline of the frontal chest radiograph to the internal diameter of the left hemithorax in normal subjects were 0.50 +/- 0.08 (mean +/- standard deviation) for male and 0.54 +/- 0.09 for female. The ratio increased with increasing left-to-right shunt [0.59(Qp/QS < 2), and 0.71 (Qp/QS > 2)] and shows a tendency of decrease with raised right ventricular systolic pressure (0.52-0.64 in normal subjects and patients with mild raised right ventricular systolic pressure and 0.43 in patients with severe raised right ventricular systolic pressure). The measurement of the angle of the line A from the vertical line tends to show increasing decrease with raised pulmonary arterial and right ventricular systolic pressure (20.1 degrees +/- 4.9 in mild PH and 10.3 degrees +/- 4.1 in moderate to severe PH). The decrease of the angle of the line A to the vertical line was well correlated with conventional radiographic criteria of the right and left central pulmonary arteries of PH.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

19.
OBJECTIVES: Our aim was to determine mechanisms underlying abnormalities of right ventricular (RV) diastolic function seen in heart failure. BACKGROUND: It is not clear whether these right-sided abnormalities are due to primary RV disease or are secondary to restrictive physiology on the left side of the heart. The latter regresses with angiotensin-converting enzyme inhibition (ACE-I). METHODS: Transthoracic echo-Doppler measurements of left- and right-ventricular function in 17 patients with systolic left ventricular (LV) disease and restrictive filling before and 3 weeks after the institution of ACE-I were compared with those in 21 controls. RESULTS: Before ACE-I, LV filling was restrictive, with isovolumic relaxation time short and transmitral E wave acceleration and deceleration rates increased (p < 0.001). Right ventricular long axis amplitude and rates of change were all reduced (p < 0.001), the onset of transtricuspid Doppler was delayed by 160 ms after the pulmonary second sound versus 40 ms in normals (p < 0.001) and overall RV filling time reduced to 59% of total diastole. Right ventricular relaxation was very incoordinate and peak E wave velocity was reduced. Peak RV to right atrial (RA) pressure drop, estimated from tricuspid regurgitation, was 45+/-6 mm Hg, and peak pulmonary stroke distance was 40% lower than normal (p < 0.001). With ACE-I, LV isovolumic relaxation time lengthened, E wave acceleration and deceleration rates decreased and RV to RA pressure drop fell to 30+/-5 mm Hg (p < 0.001) versus pre-ACE-I. Right ventricular long axis dynamics did not change, but tricuspid flow started 85 ms earlier to occupy 85% of total diastole; E wave amplitude increased but acceleration and deceleration rates were unaltered. Values of long axis systolic and diastolic measurements did not change. Peak pulmonary artery velocity increased (p < 0.01). CONCLUSIONS: Abnormalities of RV filling in patients with heart failure normalize with ACE-I as restrictive filling regresses on the left. This was not due to altered right ventricular relaxation or to a fall in pulmonary artery pressure or tricuspid pressure gradient, but appears to reflect direct ventricular interaction during early diastole.  相似文献   

20.
The status of left ventricular function in patients with chronic obstructive pulmonary disease remains controversial. With a radionuclide technique left ventricular ejection fraction, left ventricular end-diastolic volume, cardiac output, and stroke volume were measured at rest and following infusion of dextran in 23 men with severe COPD. Resting, mean LVEF was normal in 19 subjects with COPD alone; four with COPD and coronary artery disease had a depressed mean LVEF. Left ventricular end-diastolic volume index and pulmonary capillary wedge pressure were both normal at rest indicating that the left ventricle was not volume underloaded. There was a normal response to dextran infusion (750 ml.) with no deterioration in LVEF and a significant increase in cardiac index, stroke volume index, LVEDVI, and PCW. These data suggest that at rest and following volume loading with dextran left ventricular function is normal in patients with COPD.  相似文献   

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