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1.
BACKGROUND: Cardiovascular disease is the leading cause of death in chronic kidney disease (CKD) patients. Tissue Doppler velocity imaging (TVI) is a new objective method that accurately quantifies myocardial tissue velocities, deformation, time intervals and left ventricular (LV) filling pressure. In this study, TVI was compared with conventional echocardiography for the assessment of left ventricular (LV) function in pre-dialysis patients with different stages of CKD. The results obtained by TVI were used to analyse possible relationships between LV function and clinical factors such as hyperparathyroidism and hypertension that could influence LV function. METHODS: Conventional echocardiography and TVI images were recorded in 40 patients (36 men and 4 women, mean age 60+/-14 years, range 28-80 years) and in 27 healthy controls (21 men and 6 women, mean age 58+/-17 years, range 28-82 years). Twenty-two patients had mild/moderate CKD (CCr>29 ml/min; Group 1) and 18 patients had severe CKD (CCr相似文献   

2.
To determine characteristics of diastolic left ventricular (LV) function in patients on continuous ambulatory peritoneal dialysis (CAPD), two groups of CAPD patients without (n = 23; group 1) vs with (n = 25; group 2) LV hypertrophy (greater than 13 mm) were compared with a group of untreated non-renal hypertensive patients with LV hypertrophy (n = 11; group 3) using Doppler-echocardiography. Age and body surface area were comparable in all three groups, mean CAPD-duration (32 +/- 28 vs 26 +/- 23 months; p = NS) was comparable in renal patients. LV systolic function in echocardiography (LVEF: 62 vs 64 vs 63%) and systolic time intervals were normal and comparable in all three groups. Atrial maximum filling velocities (96 +/- 25 vs 91 +/- 25 vs 67 +/- 8 cm/s) were comparably increased, the ratio of maximal early/atrial filling velocities was comparably decreased (0.73 +/- 0.25 vs 0.77 +/- 0.21 vs 0.99 +/- 0.05) in both groups of renal patients as compared to group 3 (p less than 0.05-0.01). Atrial filling fractions were increased in all three groups, more pronounced in group 1 than in group 3 (50 +/- 11 vs 40 +/- 7%; p less than 0.05). The normal correlation of Doppler parameters with age and with LV radius/thickness ratio was altered in renal patients such that high patient age tended to have an additional negative influence on LV diastolic function of hypertrophied, but not of normal myocardium. Isovolumic relaxation time was prolonged in all three groups (134 +/- 38 vs 131 +/- 34 vs 116 +/- 17 ms; p = NS). We conclude that in patients on CAPD, diastolic LV filling is impaired both in normal and hypertrophied myocardium. High age is a factor that further attributes to diastolic dysfunction of hypertrophied myocardium in CAPD.  相似文献   

3.
The characteristics of left ventricular (LV) function in the nonimmunosuppressed heterotopic heart transplant (TX) with less than 3 hr of cold preservation, were studied in 12 awake chronically instrumented dogs prior to TX (control), 1-12 hr post TX (P1), 12-24 hr post TX (P2), and 24-48 hr post TX (P3). Micromanometers measured LV transmural pressure and ultrasonic transducers measured ventricular dimension in order to allow calculations of myocardial mechanical properties. Immediately after transplant (P1) there was significant (P less than 0.05) depression noted in both diastolic function and systolic function (peak LV pressure, 137 +/- 5 vs 80 +/- 10 mm Hg; dp/dtmax, 2642 +/- 170 vs 1038 +/- 98 mm Hg/sec; maximum velocity of minor axis shortening, 4.46 +/- 0.50 vs 2.41 +/- 0.56; and Emax, 6.5 +/- 1.2 vs 2.0 +/- 1.4 mm Hg/ml). However, the contractility reserve (studied in six dogs) as estimated by postextrasystolic potentiation ratio was maintained (1.41 +/- 0.07 vs 1.37 +/- 0.15), suggesting reversibility of the depressed function. Over the next 2 days the diastolic function and the systolic function (at P3: 109 +/- 6 mm Hg, 1842 +/- 450 mm Hg/sec, 5.54 +/- 0.77 cm/sec, and 4.5 +/- 1.3 mm Hg/ml, respectively) gradually improved toward control. Microscopic examination of the autopsied hearts did not show significant evidence of rejection. Thus, the early depression of function in the heart TX appeared to be the result of ischemia from preservation and surgical trauma.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

4.
OBJECTIVE: The edge-to-edge (Alfieri) mitral repair technique appears to be clinically promising, but the potential for functional mitral stenosis, especially with exercise, remains a concern. We used the myocardial marker method combined with Doppler echocardiography to evaluate mitral annular (MA) three-dimensional (3-D) dynamics and transvalvular gradients after leaflet approximation before and during dobutamine infusion. METHODS: Eight adult sheep underwent implantation of eight myocardial markers around the MA and nine in the left ventricle. Mitral leaflet edges were approximated at the valve center and micromanometers were placed in the left ventricle and atrium. The animals were studied with biplane videofluoroscopy to determine 3-D marker coordinates for computation of precise 3-D MA area and left ventricular (LV) volume. Epicardial Doppler echocardiography measured peak and mean diastolic mitral valve gradients at baseline and during dobutamine infusion (10 microg/kg per min). RESULTS: During dobutamine stimulation, left ventricular dP/dt increased from 1776+/-712 to 3390+/-618 mmHg/s (P=0.002), and cardiac output (CO) increased from 2.7+/-1.1 to 5.1+/-1.2 l/min (P=0.009). Mitral annular area (MAA) at end-diastole (ED) fell from 8.6+/-1.4 to 7.0+/-1.8 cm(2) (P=0.001) with inotropic stimulation, but only a modest increase was observed in mean (1.4+/-0.4 vs. 2.4+/-1.0 mmHg, P=0.046) and peak (2.7+/-0.8 vs. 4.9+/-2.5 mmHg, P=0.03) diastolic mitral valve gradients. MAA changed dynamically throughout the cardiac cycle, reflecting normal physiology, but the magnitude of MAA change was augmented during inotropic stimulation (18+/-5% and 27+/-4% for control and dobutamine, respectively; P=0.004). CONCLUSION: Dobutamine increased CO by 89% and decreased ED annular area by 19% after edge-to-edge repair, yet only a small increase in valve gradient occurred. Marker analysis showed enhanced dynamic motion of the mitral annulus. Thus, the edge-to-edge mitral valve repair was not associated with substantial transvalvular obstruction during high flow conditions and did not perturb normal MA 3-D dynamics in normal ovine hearts.  相似文献   

5.
OBJECTIVE: Based on the law of Laplace, transventricular tension members were designed to diminish wall stress by changing the left ventricle (LV) globular shape to a bilobular one, thus reducing the ventricular wall radius of curvature. This concept was tested in a model of congestive heart failure. METHODS: Seven calves were used for the study (74.3+/-4.2 kg). Treatment efficacy was assessed with sonomicrometric wall motion analysis coupled with intraventricular pressure measurement. Preload increase was applied stepwise with tension members in released and tightened position. RESULTS: Tightening of the tension members improved systolic function for CVP>10 mmHg (dP/dt: 828+/-122 vs. 895+/-112 mmHg/s, P=0.019, for baseline and 20% stress level reduction respectively; wall thickening: 11.6+/-1.5 vs. 13.3+/-1.7%, P<0.001) and diastolic function (LV end-diastolic pressure: 15.9+/-4.8 vs. 13.6+/-2.7 mmHg, P<0.001, for CVP>10 mmHg; peak rate of wall thinning: -12.2+/-2.2 vs. -14+/-2.3 cm(2)/s, P<0.001 and logistic time constant of isovolumic relaxation: 48.4 +/-10.9 vs. 39.8+/-9.6ms, P<0.001, for CVP>5 mmHg). CONCLUSIONS: This less aggressive LV reduction method significantly improves contractility and relaxation parameters in this model of congestive heart failure.  相似文献   

6.
OBJECTIVE: In this study, the relationship V(f)AR, which was obtained from carotid blood-flow velocity (V(f)) and the cross-sectional area (A) of the left ventricle, was used to assess changes in left ventricular (LV) systolic performance as indicated by the LV pressure-volume relationship (PVR) and end-systolic LV elastance (E(es)). BACKGROUND: The relationship of maximum systolic V(f) as a surrogate for LV pressure and end-systolic LV area as a surrogate for end-systolic LV volume may allow for the estimation of LV elastance and ejection properties. METHODS: In 25 pigs, internal carotid V(f) was recorded by using continuous-wave Doppler mode. Echocardiographic measurements of A were continuously performed with an automated border detection system and combined with data for V(f) to display V(f)AR as a series of loop diagrams. These were shifted during acute preload reduction, and an index E'(es) was calculated by applying the time varying elastance concept to end-systolic V(f)AR. Simultaneously, E(es) was acquired by conductance catheter and micromanometer techniques. Comparisons of E'(es) and E(es) were made at various contractility levels obtained by the administration of dobutamine, 5 microg/kg/min, and esmolol, 40 to 60 mg, and at various cardiac load levels, obtained by a fluid bolus infusion or administration of a vasoconstrictor. RESULTS: Highly linear elastance curves (r >or= 0.85, p < 0.0001) were derived from both end-systolic V(f)AR and PVR. Correlation of E'(es) and E(es) revealed an almost linear function: E'(es) = 0.052 + 0.11 E(es) (r = 0.98, p < 0.0001). Administration of dobutamine increased E(es) from 5.8 +/- 3.04 mmHg/mL to 10.1 +/- 4.19 mmHg/mL (p < 0.05), and E('es) from 0.68 +/- 0.288 cm(2)/min/mL to 1.24 +/- 0.458 cm(2)/min/mL (p < 0.05). After administration of esmolol, E(es) and E'(es) both dropped significantly by 3.7 +/- 2.4 mmHg/mL and 0.44 +/- 0.15 cm(2)/min/mL, respectively. No load dependency of E'(es) was seen. Bland-Altman analysis revealed that the change in E'(es), which is required to predict a significant change in E(es), should exceed +16.9% or -13.1% of the preceding value. CONCLUSION: Application of the time-varying elastance concept on the relation of V(f) and LV area allows for the determination of an index E'(es) that may be used to estimate E(es).  相似文献   

7.
BACKGROUND: In patients with pulmonary oedema and preserved renal function, furosemide has not only a renal, but also a vascular effect, causing a rapid fall in left ventricular filling pressure accompanied by an increase in venous compliance. Previous studies have shown conflicting findings regarding the vascular effects of furosemide in patients with end-stage renal disease (ESRD). The objective of our study was to investigate whether furosemide induces changes in central cardiac haemodynamics in anuric ESRD patients, using conventional echocardiography and colour tissue Doppler velocity imaging (TVI), a new quantitative and sensitive method. METHODS: Repeated low doses (40 mg followed by an additional dose of 40 mg after 30 min) of i.v. furosemide were administered to 12 (61.6 +/- 16 years, 7 men) and a high dose (250 mg) of i.v. furosemide to 6 (64.1 +/- 3.6 years, 5 men) clinically stable anuric haemodialysis (HD) patients. Conventional two-dimensional echocardiography and colour TVI images were recorded immediately before (0 min) the furosemide infusion in both groups, and in the group receiving the repeated low-dose infusion (at 0 and 30 min), 10, 20, 30, 40, 50 and 70 min after the administration of the first infusion. In the group receiving the single high dose of furosemide the ultrasound investigation was repeated 10, 20, 30 and 40 min after the infusion. The myocardial tissue velocities (v; cm/s) for isovolumetric contraction (IVC), peak systole (PS), early (E') and late (A') myocardial diastolic filling velocities were measured in the left ventricle (LV) at six sites (infero-septal, antero-lateral, inferior, anterior, infero-lateral and antero-septal walls) at the basal region. IVC time (IVCT), IV relaxation time (IVRT), PS time (PSt), RR interval, mitral annulus motion (MAM), strain rate (SR), left ventricular filling pressure (E/E') and cardiac output were also measured. The average of the different walls was used to evaluate global function. Right ventricle (RV) dynamics was evaluated from measurements of IVC velocity (IVCv), peak systolic velocity (PSv), E' and A' from the RV free wall. RESULTS: No significant changes in cardiac output, IVCv, PSv, SR, MAM, E', A', E'/A', IVRT and LV filling pressure were observed, indicating that neither 40 mg (plus additional 40 mg after 30 min) nor 250 mg of furosemide had any measurable effects on LV filling pressure and LV and RV systolic and diastolic function. CONCLUSIONS: In anuric HD patients, low and high doses of furosemide had no significant effects on central cardiac haemodynamics. Therefore, the use of furosemide infusion in anuric ESRD patients with acute pulmonary oedema is not supported by the results of this study.  相似文献   

8.
OBJECTIVE: To correlate supraclavicular ultrasonography at rest and in hyperaemic response with angiographically patent and (distal) 'string sign' left internal mammary artery (LIMA) to left anterior descending (LAD) area grafts. METHODS: Fifty-three patients with LIMA to LAD area grafting were prospectively entered in a follow-up study. Arteriography (native and LIMA) was performed at 1.4+/-0.8 years postoperatively and ultrasonography was performed at rest, in hyperaemic response and 2min after hyperaemic response at 1.8+/-0.8 years postoperatively and was compared to arteriography. Ultrasonographic parameters analysed were systolic and diastolic peak velocity, systolic and diastolic velocity integral, diastolic/systolic peak velocity ratio and diastolic/total velocity integral ratio. RESULTS: One patient was excluded because obesity hampered ultrasonography. Arteriography demonstrated functional grafts in 43 patients (group I), sequential distal 'string sign grafts' in 4 patients (group II) and total 'string sign grafts' in 5 patients (group III). Between the groups all ultrasonographic velocities showed a significant linear relation (p相似文献   

9.
BACKGROUND: Good blood pressure (BP) control has been reported previously in haemodialysis (HD) patients receiving 8-h dialysis sessions. Home HD allows patients to dialyze for long periods, but there are few data on the BP control achieved by these patients. We studied BP control, using ambulatory blood pressure monitoring (ABPM), in our home-HD patients who were receiving long-hours dialysis. METHODS: Twenty-four patients aged 52.7+/-11 years underwent ABPM. They had been on home HD for 52.9+/-39 months and dialysed for 7.2+/-1.1 h thrice weekly. Two patients were taking antihypertensive drugs. Historical data on BP and weight gains were obtained from the patients' own records. Left ventricular (LV) mass was assessed by echocardiography and total body water (TBW) by bioelectrical impedance. RESULTS: The mean 24-h BP was 129+/-17 mmHg (systolic) and 83+/-14 mmHg (diastolic). The daytime BP was 131+/-17 mmHg (systolic) and 84+/-14 mmHg (diastolic), while the night-time BP was 126+/-22 mmHg (systolic) and 81+/-17 mmHg (diastolic). Six patients (25%) had a normal circadian BP rhythm, but the rest showed a subnormal fall or an increase in BP at night. Mean 24-h BP did not correlate significantly with time on dialysis, dialysis session length, Kt/V, haemoglobin, interdialytic weight gain, or TBW. Twenty-one patients (87%) had LV hypertrophy and 16 of these had diastolic dysfunction. LV mass index was inversely correlated with nocturnal BP fall (r=-0.54, P=0.03). Non-dippers had been treated longer than dippers (29 vs 59.2 months, P=0.03) but they were similar in respect to age, dialysis session length or Hb concentration. CONCLUSIONS: Long, slow haemodialysis at home provides satisfactory daytime BP control in the majority of patients without the need for antihypertensive drugs but abnormal circadian BP rhythm and LV hypertrophy remain common.  相似文献   

10.
BACKGROUND: Overhydration and accumulation of uraemic toxins may influence the myocardial function in haemodialysis (HD) patients. To evaluate cardiac function and the effects of fluid and solute removal during a single session of HD, colour tissue velocity imaging (TVI) was used. This new technique, which is less load dependent than conventional echocardiography, allows an objective quantitative assessment of myocardial contractility, contraction and relaxation. METHODS: Conventional echocardiographic and TVI images were recorded before and after a single HD session in 13 clinically stable HD patients (62+/-10 years, six males) and in 13 sex- and age-matched healthy controls. Myocardial tissue velocities (v; cm/s) for isovolumetric contraction (IVC), peak systole (PS), early (E') and late (A') diastolic filling and strain rate (SR) were measured. RESULTS: Left ventricular hypertrophy (LVH) was present in 12 patients. TVI gave additional information in comparison with conventional echocardiography. Before HD, PS (5.0+/-0.8 vs 6.0+/-1.2 cm/s, P<0.05), E' (5.7+/-1.7 vs 7.3+/-2.0 cm/s, P<0.05) and A' (6.6+/-1.7 vs. 8.3+/-2.9 cm/s, P<0.05) velocities were lower in the patients than in the controls, indicating systolic and diastolic dysfunction. The HD session increased IVCv (4.0+/-1.7 to 5.5+/-1.9 cm/s; P<0.001), PSv (5.0+/-0.8 to 5.7+/-0.8 cm/s; P<0.05) and SR (0.7+/-0.2 to 0.9+/-0.2 1/s; P < 0.05) and decreased E/E' (16.7+/-7.7 to 12.2+/-4.0, P<0.05), indicating improved systolic function and decreased LV filling pressure, respectively. Linear regression analysis demonstrated a dependency of systolic contraction (PSv) and contractility (IVCv) upon plasma levels of phosphate (r(2) = 0.70, P<0.005, r(2) = 0.33, P<0.01). CONCLUSIONS: Using TVI, HD patients demonstrate myocardial dysfunction, which is found less frequently when using conventional echocardiography. The systolic function seems to be impaired by high plasma levels of phosphate and an increased Ca x P product. One single session of HD improved systolic function as indicated by increases in IVCv, PSv and SR. Further studies are needed to clarify if this effect of HD is due to the acute removal of fluid, the removal of solutes or both.  相似文献   

11.
Microalbuminuria in hypertension is not a determinant of insulin resistance   总被引:4,自引:0,他引:4  
BACKGROUND: Microalbuminuria (MA) clusters with metabolic derangements linked to the insulin resistance syndrome, and is associated with increased risk of cardiovascular disease in both diabetes and hypertension. This study questioned if MA, reflecting endothelial damage, is directly linked to impaired insulin action. METHODS: MA was measured in two 24-hour urine samples in 84 persons with untreated hypertension recruited from a population survey (diastolic blood pressures 90 to 105 mm Hg). Thirty-one percent had MA values>20 microg/min (MA group, N = 26), and these were matched according to age, gender, and body-mass index with hypertensive persons without MA (non-MA group, N = 32) for comparison of the metabolic profile. Insulin sensitivity was measured with clamp techniques. RESULTS: The MA and non-MA groups were similar in their fasting and post-load glucose and insulin levels, in the first (930 +/- 594 vs. 1097 +/- 707 pmol/L) and second (1111 +/- 662 vs. 1163 +/- 702 pmol/L) phases of insulin release during a hyperglycemic clamp, and in their insulin sensitivity indices (0.16 +/- 0.10 vs. 0.17 +/- 0.13, P> 0.3 for all). The MA group had higher systolic blood pressure (157 +/- 13 vs. 150 +/- 12 mm Hg, P = 0.05) and a higher serum level of circulating advanced glycation end products (AGEs; 11.0 +/- 3.0 vs. 7.9 +/- 3.5 U/mL, P = 0.05) than the controls. No associations were found between MA and the insulin sensitivity index, or glucose and insulin levels. Weak associations were found with systolic blood pressure (r = 0.25, P = 0.05), AGEs (r = 0.27, P = 0.05), and smoking habits (r = 0.39, P = 0.01). CONCLUSION: In hypertension, MA is not a determinant of insulin resistance, provided confounding factors such as degree of adiposity are carefully controlled.  相似文献   

12.
BACKGROUND: A number of experimental studies have suggested that cyclosporine (CsA) toxicity induces cardiac modifications which may cause diastolic dysfunction over the course of time. Doppler echocardiography with tissue Doppler imaging (TDI) could consistently detect diastolic dysfunction. The purpose of this study was to assess diastolic dysfunction using C2 monitoring of CsA exposure in stable renal transplant patients. PATIENTS AND METHODS: Seventy-eight kidney recipients including 42 men and 36 women of overall mean age of 52 +/- 9 years were obtained in 47 living and in 31 cases from cadaveric donations over 12 or more months after transplantation using cases from CsA, mycophenolate mofetil, and steroid. C2 levels were measured by an enzyme multi-immune assay technique. The patients underwent conventional and Doppler echocardiography with TDI. RESULTS: The patients were divided into 2 groups according to C2 levels less than 500 mug/L (group 1, n = 40) versus greater than 500 mug/L (group 2, n = 38). The demographic parameters, serum creatinine and lipid levels, systolic and diastolic blood pressures, number and type of antihypertensive medications, and conventional echocardiographic parameters did not differ significantly between the groups. However, group 1 patients showed significantly higher isovolumic relaxation time (109 +/- 27 vs 86 +/- 14 ms), early diastolic deceleration time (189 +/- 52 vs 137 +/- 59 ms), and lower values of E velocity (56 +/- 32 vs 92 +/- 27 cm/s) and E/A ratios (0.81 +/- 0.23 vs 1.15 +/- 0.46) than group 2. TDI studies revealed significantly lower E'/A' (0.76 +/- 0.25 vs 1.09 +/- 0.32, P < .05) in group 1 versus group 2. CONCLUSION: The data suggested that the higher C2 levels may induce diastolic dysfunction in the hearts of kidney recipients without impairment of contractile performance.  相似文献   

13.
Minimally invasive surgery for coronary revascularization using the left internal thoracic artery (ITA) has gained increasing interest. For control of graft function the established transcutaneous color-Doppler echocardiography in combination with a stress-test was performed to test the ability of this novel technique. Twenty-one patients having received a single ITA-graft were evaluated early postoperatively at rest and during isometric stress test with a handgrip exercise. Compared to the right internal thoracic artery, the mainly systolic flow is changed to a wide diastolic component when the left ITA is anastomosed to the coronary artery. The peak systolic/peak diastolic velocity ratio changed from 4.5+/-1.9 to 1.4+/-0.47 (P<0.0001). During stress reaction with the isometric handgrip maneuver the grafted ITA showed a significant increase of the mean diastolic flow (29.1+/-13.3 to 44.3+/-14.7 cm/s, P<0.0001) and total blood flow (124.8+/-55.4 ml/min to 176.6+/-71.7 ml/min), which may demonstrate an efficient bypass function. We conclude, that the noninvasive measurement of ITA-graft function with Doppler-ultrasound may be a clinically useful method to assess the functional status after minimally invasive coronary artery bypass grafting. In combination with the hand-grip test it represents a valid new technique with the potential to estimate graft patency.  相似文献   

14.
OBJECTIVE: To measure the changes in systolic and diastolic left ventricular function that occur during off-pump coronary artery bypass grafting (OPCAB) as a consequence of positioning the heart and interrupting coronary flow. METHODS: 2-D Transoesophageal echocardiography was used to derive systolic wall motion indices and pulsed Doppler parameters of diastolic function including the E/A ratio, PVS/PVD ratio, and deceleration time. A continuous cardiac output thermodilution pulmonary artery catheter was used to provide hemodynamic measures of left ventricular function. Data was obtained prior to, during and following coronary grafting. RESULTS: Thirty-four consecutive anastomoses were evaluated, including eight circumflex (LCX), 17 left anterior descending artery (LAD) and nine right coronary artery (RCA) anastamoses. Significant changes in diastolic and systolic cardiac function were identified in those patients who underwent LCX grafting. Specifically during LCX grafting, both wall motion score index (2.4+/-1.4 vs 1.5+/-0.63 and 1.9+/-0.91) and the E/A ratio were significantly increased (3.5+/-1.4 vs 1.1+/-0.33 and 1.2+/-0.44) when compared to RCA and LAD grafting, respectively. The PVS/PVD ratio was significantly decreased during left circumflex grafting (0.7+/-0.45 vs 1.1+/-0.19 and 1.0+/-0.58) when compared to RCA and LAD grafting, respectively. All functional parameters returned to baseline by the end of surgery. CONCLUSIONS: Multivessel OPCAB can be achieved with mild impairment of left ventricular function that returns to baseline by the end of the procedure. Impairment of diastolic function is most marked during circumflex grafting as demonstrated by a restrictive filling pattern. Measures of diastolic function may be helpful in developing better strategies for exposure of the circumflex graft site.  相似文献   

15.
Y Kuwagata  H Sugimoto  T Yoshioka  T Sugimoto 《The Journal of trauma》1992,32(2):158-64; discussion 164-5
Left ventricular (LV) contractile and diastolic performance was evaluated in patients with thermal injury or multiple trauma using precordial and transesophageal echocardiography. Thirty-nine patients were divided into four groups: group B1 (within 24 hours after thermal injury); group B2 (from 24 to 72 hours after thermal injury); group M (multiple trauma); and a control group (outpatients). Left ventricular contractile indices, including ejection fraction, mean velocity of circumferential fiber shortening, and the ratio of systolic blood pressure to LV end-systolic dimension, were not impaired in any of the experimental groups. The ratio of LV filling volume during rapid filling to stroke volume, obtained from M-mode echocardiography as an index of LV distensibility, was significantly decreased in groups B1 (44.5% +/- 8.8%) and B2 (46.8% +/- 8.5%) compared with controls (61.9% +/- 7.4%) (p less than 0.05). The ratio of the peak velocity in the atrial contraction phase to that in the rapid filling phase, obtained using pulsed Doppler echocardiography, also showed significant impairment of LV distensibility in groups B1 (1.08 +/- 0.12) and B2 (1.09 +/- 0.07) compared with controls (0.71 +/- 0.12) (p less than 0.01). Group M showed no significant impairment of these diastolic indices. A profound depression of LV diastolic function thus occurs following thermal injury but not following multiple trauma.  相似文献   

16.
OBJECTIVE: Left ventricle (LV) function was shown to be a principal determinant of morbidity and mortality in both uncorrected and surgically corrected mitral regurgitation (MR). However, the cellular mechanisms that develop in the LV remodeling secondary to volume overload in chronic severe MR is still not well defined. In single ventricular myocyte, a reduced contraction and slowed relaxation have been mainly attributed to defective intracellular Ca2+ currents. Between several Ca2+ handling proteins, sarcoplasmic reticulum Ca2+-ATPase 2 (SERCA2) expression and activity determines not only the extent and rate of relaxation, but also the rate and amplitude of contraction. The aim of the study was to determine whether modifications of SERCA2 gene expression occurs in LV wall remodeling process secondary to chronic severe MR. METHODS: The LV samples were obtained from 12 patients presented LV wall remodeling (LV: diastolic/systolic diameter-70+/-7 mm vs 46+/-10 mm; diastolic/systolic volume-260+/-65 ml vs 102+/-68 ml) due to chronic, severe MR. Expressions of SERCA2 isoforms-SERCA2a and 2b mRNAs were estimated by semiquantitative RT-PCR and normalized to GAPDH. The protein levels of SERCA2 were determined by Western blot after normalization to actin. Results were compared with samples from non-failing human hearts (NFH). RESULTS: On SERCA2 mRNA levels, important reduction on both SERCA isoforms SERCA2a (-40%) and SERCA2b (-49%) compared to NFH, together with significant correlation between isoforms (r = 0.89; p = 0.01) were observed. SERCA2 protein levels were decreased (-38%) in MR compared to NFH. Also significant correlations between SERCA2a/2b and SERCA2 protein expression (r = 0.83, p = 0.017; r = 0.68, p = 0.05, respectively) were observed. Moreover, a negative correlation between protein levels of SERCA2 (r = -0.64, p = 0.053) and left ventricular diastolic diameter was observed. CONCLUSIONS: In chronic volume overload the down-regulation of SERCA2a and 2b at the mRNA and SERCA2 protein levels exist. Moreover, protein levels of SERCA2 tend to correlate to the grade of left ventricular diastolic dilatation and suggest an important role LV remodeling.  相似文献   

17.
BACKGROUND: Orthotopic heart transplantation is a life-saving therapy for children with end-stage heart disease. However, 50% of these transplanted children die or require re-transplantation 12 years later. Progressive deterioration of cardiac function is a common feature of long-term survivors; however, quantitative evaluation of the state of the right ventricle has been lacking. Tissue Doppler imaging (TDI) has been used to measure alterations in right ventricular (RV) function in other illnesses. The purpose of this study was to quantitate abnormalities in tricuspid annular systolic and diastolic velocities as an indicator of RV dysfunction, and to evaluate if time since transplantation and the presence of tricuspid regurgitation are associated with quantitative changes in tricuspid annular velocities in pediatric heart transplant recipients. METHODS: TDI was performed and velocities recorded during systole and early and late diastole at the tricuspid annulus, septum and mitral annulus in transplanted patients and in a control group with normal hearts. Pulsed wave Doppler mitral and tricuspid inflows were also measured and the severity of tricuspid regurgitation was estimated using color flow mapping. Patients with biopsy evidence of active cellular rejection or left ventricular ejection fraction of <60% were excluded from study. RESULTS: Thirty-five patients were divided into a normal heart group (n = 14) and a transplant group (n = 21), aged from 1 to 23 years. Systolic and early diastolic velocities at the tricuspid annulus and septum in the transplant group were reduced significantly compared with the normal group (p < 0.05): tricuspid annular systolic, 5.8 +/- 1.4 vs 9.4 +/- 1.7 cm/sec; early diastolic, -6.4 +/- 2.6 vs -9.7 +/- 2.6 cm/sec; septum systolic, 3.9 +/- 1.5 vs 5.8 +/- 1.4 cm/sec; and early diastolic, -6.3 +/- 2.4 vs -9.1 +/- 2.5 cm/sec. Patients were divided into early (<5 years) and late (>5 years) term groups since transplantation. Tissue velocities at the tricuspid annulus in the late term group had further reduction in systole, 4.9 +/- 1.4 vs 6.4 +/- 1.1 cm/sec, and early diastole, -5.3 +/- 1.5 vs -7.1 +/- 2.9 cm/sec (p < 0.05). Patients with severe tricuspid regurgitation had systolic and early diastolic velocities at the tricuspid annulus that were further reduced. Left ventricular mitral inflow Doppler early/late diastolic ratios became significantly different from the normal group 5 years after transplantation (p < 0.05). CONCLUSIONS: TDI demonstrated that tricuspid annular systolic and early diastolic velocities were abnormal in children after transplantation and became significantly more abnormal with prolonged time after transplantation. These alterations were not dependent on the presence of severe tricuspid regurgitation but appeared to be exacerbated by its presence. Evidence of diastolic left ventricular dysfunction was not detected before 5 years after transplantation in this unselected group. A prospective study may be required to define the evolution and progression of right and left ventricular dysfunction in children after heart transplantation.  相似文献   

18.
The purpose of this study was to determine the effects of a successful renal transplantation on left ventricular (LV) morphology, systolic and diastolic function. Forty-three renal transplant patients prospectively studied by echocardiography (30 months follow-up) were divided into two groups. The first echocardiographic examination was performed 3.0 +/- 2.8 months after renal transplantation in group I (11 men, 12 women); and 34.4 +/- 29.1 months after transplant in group two (9 men, 11 women). We noticed the following changes in blood pressure (BP): group 1 systolic BP reduction (from 140.5 +/- 23.6 to 126 +/- 6.8 mmHg; P < .01), and pulse pressure reduction (from 59.5 +/- 14.9 to 47.5 +/- 9.8 P < .05); group 2, diastolic BP acceleration (from 78.4 +/- 8.7 to 84 +/- 6.9 mmHg, P < .05). LV mass index decreased in group 1 (from 126.4 +/- 18.0 g/m2 to 104.6 +/- 15.9 g/m2, P < .05). The incidence of LV hypertrophy (LVH) decreased in group 1 from 70% to 40% (P < .05). Only one parameter of systolic function-end systolic stress-significantly decreased in both groups: group 1 from 78 +/- 11 to 61 +/- 12 g/cm2; group 2 from 63.8 +/- 9.0 to 55.1 +/- 9.0 g/cm2, P < .05). The pattern of mitral inflow changed: in group 1, the normal pattern decreased from 30% to 20% and the restrictive pattern increased from 0% to 10%; in group 2, the normal mitral inflow pattern decreased from 60% to 20% and abnormal relaxation type increased from 40% to 80%. Regression of LVH after renal transplant improved LV geometry and systolic function. Despite better systolic function a progression of LV diastolic dysfunction was noticed, which might be explained by cyclosporine treatment. Renal transplantation exerted a beneficial impact on cardiomyopathy manifested by LVH and systolic dysfunction.  相似文献   

19.
OBJECTIVE: To study the effect of aerobic treadmill exercise training with different intensity on left ventricular (LV) function in patients with stable coronary artery disease, using Strain Rate- and Tissue Doppler Imaging. DESIGN: Seventeen patients were randomly assigned to either moderate (50-60% of peak oxygen uptake (VO(2peak)) or high intensity exercise (80-90% of VO(2peak)) for 10 weeks. RESULTS: The increase of VO(2peak) was significantly higher (p=0.01) in the high intensity group (17 vs. 8%). Mean LV early diastolic strain rate increased in the high, but not in the moderate, intensity group. For systolic strain rate or mitral annular velocities there were no change after training in either group. CONCLUSIONS: Aerobic treadmill exercise improves early diastolic relaxation in patients with stable coronary artery disease, measured by the mean LV early diastolic strain rate.  相似文献   

20.
BACKGROUND: The effects of clinical doses of propofol on left ventricular (LV) systolic function remain controversial and LV diastolic function has not been evaluated during induction of anesthesia with propofol. We assessed the effects of propofol on LV systolic and diastolic function during induction of anesthesia in adult patients with transthoracic echocardiography. METHODS: Twenty-three patients, ASA 1-2 and age < 70 y.o., received propofol 2 mg x kg(-1) for induction of anesthesia. LV systolic function was evaluated by fractional shortening (FS), ejection fraction (EF), rate-corrected mean velocity of circumferential fiber shortening (Vcfc) and a contractile index, LV end-systolic wall stress (ESWS) versus Vcfc relation (ESWS-Vcfc relation). LV diastolic functions were assessed by analysis of transmitral flow velocity, peak early diastolic and late diastolic filling velocities (E wave and A wave), E/A ratio and E wave deceleration time (DT). RESULTS: After induction, propofol preserved FS, EF, Vcfc and ESWS-Vcfc relation and caused a significant decrease in E wave and A wave, and a significant increase in E/A ratio and maintained DT. CONCLUSIONS: During induction of anesthesia in adult patients, propofol preserved LV systolic and diastolic functions.  相似文献   

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