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1.
Mitral inflow filling pattern usually consists of 2 forward flow velocities in sinus rhythm: early rapid filling (E) and late filling with atrial contraction (A). However, additional mid-diastolic flow velocity may be present resulting in triphasic mitral inflow filling pattern. When mitral inflow is triphasic, mitral annulus velocity recorded by tissue Doppler imaging (TDI) frequently demonstrates a mid-diastolic component (L'). The significance of L' has not been explored previously. The purpose of this study was to explore possible mechanisms and clinical implications of triphasic mitral inflow with or without L' using TDI and proBNP. Of 9004 patients who underwent transthoracic echocardiography from March to November 2003, 83 (0.9%) patients (33 male, 50 female; mean age, 63+/-10 years) with a triphasic mitral inflow velocity pattern, including mid-diastolic flow velocity of at least 0.2m/s, and sinus rhythm were prospectively identified in our clinical echocardiography laboratory. Peak velocity of E, mid-diastolic (L), and A, and deceleration time (DT) of the E wave velocity were measured. Diastolic mitral annular velocities were measured at the septal corner of the mitral annulus by TDI from the apical 4-chamber view. ProBNP was measured at the time of echocardiogram using a quantitative electrochemiluminescence immunoassay. Mean heart rate was 54+/-6 beats/min (range, 40-67). Mean left ventricular (LV) ejection fraction (EF) was 64+/-13% and LV systolic dysfunction (EF<40%) was present in only 6 (7%). Patients were classified into 2 groups: group 1 (n=47) included those who had L' and group 2 (n=36) included those without L'. Group 1 patients had significantly higher peak velocity (35+/-14 vs 26+/-6 cm/s, p=0.0002) and TVI (35+/-14 vs 26+/-6 cm/s, p=0.0002) of L, E/E' (18+/-8 vs 14+/-6, p=0.02), and left atrial volume index (42+/-14 vs 34+/-10 ml/m(2), p=0.0037). E' (4.7+/-1.3 vs 6.2+/-2.3 cm/s, p=0.001) and A' (6.2+/-2.0 vs 8.6+/-3.4 cm/s, p=0.0006) were significantly lower in group 1 compared with those of group 2. ProBNP was significantly higher in group 1 (847+/-1461 vs 438+/-1039 pmol/l, p=0.0012) and it was above normal in all except in 1 patient of group 1. In conclusion, the presence of L' in subjects with triphasic mitral inflow velocity pattern with mid-diastolic flow is associated with higher E/E', elevated proBNP and enlarged left atrium indicating advanced diastolic dysfunction with elevated filling pressures. This unique mitral annular velocity pattern should be helpful in identifying the patients with advanced diastolic dysfunction and increased LV filling pressures.  相似文献   

2.
Left ventricular (LV) diastolic function is an important predictor of morbidity and mortality after acute myocardial infarction (AMI). We evaluated the role of diastolic function in predicting in-hospital events and LV ejection fraction (EF) 6 months after a first AMI that was treated with primary percutaneous coronary intervention (PCI). We prospectively enrolled 59 consecutive patients who were 60 +/- 15 years of age (48 men), presented at our institution with their first AMI, and were treated with primary PCI. Patients underwent 2-dimensional and Doppler echocardiography, including tissue Doppler imaging of 6 basal mitral annular regions within 24 hours after primary PCI and were followed until discharge. Clinical and echocardiographic variables at index AMI were compared with a combined end point of cardiac death, ventricular tachycardia, congestive heart failure, or emergency in-hospital surgical revascularization. Follow-up echocardiographic assessment was performed at 6 months in 24 patients. During hospitalization, 3 patients died, 7 developed congestive heart failure, 4 had ventricular tachycardia, and 1 required emergency surgical revascularization. Stepwise logistic regression analysis showed the ratio of early mitral inflow diastolic filling wave (E) to peak early diastolic velocity of non-infarct-related mitral annulus (p < 0.01) (E') and mitral inflow E-wave deceleration time (p < 0.02) to be independent predictors of in-hospital cardiac events (generalized R2 = 0.66). In a stepwise multiple linear regression model, independent predictors of follow-up LVEF were mitral inflow deceleration time (R2 = 0.39, p = 0.002), baseline LVEF (R2 = 0.54, p < 0.02), and mitral inflow peak early velocity/mitral annular peak early velocity (or E/E') of infarct annulus (R2 = 0.66, p = 0.02). In conclusion, in patients who are treated with primary PCI for a first AMI, E/E' velocity ratio and mitral inflow E-wave deceleration time are strong predictors of in-hospital cardiac events and of LVEF at 6-month follow-up.  相似文献   

3.
Although antiplatelet therapy with a specific inhibitor of phosphodiesterase-3 cilostazol improves stent patency compared with use of aspirin (ASA) alone, the specific role of cilostazol on platelet aggregation in patients with acute myocardial infarction (AMI) is less well understood. Thirty-six patients with AMI who were successfully treated with primary angioplasty were randomized to 3 antiplatelet regimens: ASA alone (n = 12), ASA + ticlopidine (n = 12), and ASA + cilostazol (n = 12). We measured shear stress-induced platelet aggregation (SIPA) using a modified cone-plate viscometer on admission and on day 7, and evaluated the inhibitory effects of combination therapy with ASA + cilostazol on SIPA. Compared with cases of stable coronary artery disease, significant increases in SIPA and plasma von Willebrand factor activity were observed in patients with AMI before they received antiplatelet therapy. On day 7 after primary angioplasty, ASA did not inhibit SIPA (65 +/- 15% vs 57 +/- 11%, p = 0.086), whereas both combination therapies of ASA + ticlopidine and ASA + cilostazol significantly inhibited SIPA in patients with AMI (ASA + ticlopidine: 61 +/- 15% vs 45 +/- 13%, p <0. 0001; ASA + cilostazol: 64 +/- 14% vs 43 +/- 9%, p <0.005). There was a significant correlation of SIPA with adenosine diphosphate (ADP)-induced platelet aggregation (r = 0.412, p = 0.003) and with plasma von Willebrand factor activity (r = 0.461, p = 0.0008). These data suggest that patients with AMI have increased platelet aggregability in response to high shear stress. Combined antiplatelet therapy with ASA + cilostazol appears to be as effective as therapy with ASA + ticlopidine for reducing SIPA in patients with AMI who are undergoing primary angioplasty.  相似文献   

4.
It is unknown whether right ventricular (RV) tissue Doppler (TD) predicts outcome in patients with left ventricular (LV) heart failure (HF) independently of contemporary echocardiographic Doppler variables of LV diastolic function. Comprehensive echocardiographic Doppler examination was performed before discharge in 107 patients hospitalized with LV HF. The primary end point was cardiac death or rehospitalization for HF. Follow-up was complete for 100 of 107 patients a mean of 527 days after hospital discharge. There were no significant differences in baseline clinical variables (mean age 58+/-12 years, 46% women, 77% hypertensive, 48% diabetic, 41% current smokers, and 23% known coronary artery disease) in prediction of the primary end point. Compared with patients without an event, patients with an event had a larger left atrial volume index (42+/-16 vs 33+/-13 ml/m2, p=0.001), lower LV ejection fraction (35+/-19% vs 46+/-22%, p=0.01), higher mitral peak early diastolic flow velocity/TD early diastolic velocity (19+/-7 vs 14+/-7, p=0.001), lower RV fractional area change (39+/-11% vs 43+/-10%, p=0.04), and lower RV TD systolic velocity (8+/-2 vs 10+/-3 cm/s, p=0.005). On Cox proportional hazards multivariate analysis, left atrial volume index (p=0.01), mitral peak early diastolic flow velocity/TD early diastolic velocity (p=0.03), and RV TD systolic velocity (p=0.04) were independent predictors of outcome. Even when contemporary echocardiographic Doppler measures of LV diastolic function are considered, RV TD systolic velocity is an independent predictor of cardiac death or rehospitalization for HF in patients hospitalized with HF and appears to be superior to conventional 2-dimensional parameters of RV function.  相似文献   

5.
BACKGROUND: The novel parameter T(E-E'), which is the time interval between the onset of the early diastolic mitral inflow velocity (E) and the early diastolic mitral annular velocity (E'), is reported to be related to the constant of the left ventricular (LV) relaxation, and T(E-E') is also reported to be useful for predicting the LV filling pressure. METHODS AND RESULTS: To investigate the effect of preload reduction via hemodialysis on T(E-E'), 28 pairs of echocardiographic evaluations were performed just before and immediately after hemodialysis, including the measurement of the T(E-E') as well as measurement of the conventional echocardiographic parameters. The baseline T(E-E') was 17.9 +/-28.1 ms, which correlated with the ratio of E/E' (r=0.49, p=0.008). After hemodialysis, T(E-E') was shortened to -3.2+/-34.1 ms, which was a significant change from baseline (p=0.001). CONCLUSIONS: As T(E-E') is a preload dependent parameter, the intravascular volume status should be taken into account when the clinical application of T(E-E') is considered as an index of LV relaxation.  相似文献   

6.
Ha JW  Cho JR  Kim JM  Ahn JA  Choi EY  Kang SM  Rim SJ  Chung N 《Chest》2005,128(5):3428-3433
BACKGROUND: Although impaired left ventricular (LV) diastolic function is a prominent feature of hypertrophic cardiomyopathy (HCM), diastolic function and its relation to exercise capacity in apical HCM (ApHCM) has not been explored previously. This study was sought to determine the relationship between diastolic mitral annular velocities combined with conventional Doppler indexes and exercise capacity in patients with ApHCM. PATIENTS: Twenty-nine patients with ApHCM (24 men; mean age +/- SD, 57 +/- 10 years) underwent supine bicycle exercise with simultaneous respiratory gas analysis and two-dimensional and Doppler echocardiographic study. RESULTS: The mitral inflow velocities (early filling [E], late filling, and deceleration time) were traced and measured. Early diastolic mitral annular velocity (E') was measured at the septal corner of mitral annulus by Doppler tissue imaging (DTI) from the apical four-chamber view. Pro-brain natriuretic peptide (proBNP) was measured at the time of echocardiography using a quantitative electrochemiluminescence immunoassay. E/E' ratio correlated inversely with maximal oxygen uptake (Vo(2)max) [r = - 0.47, p = 0.0106]. There was a significant positive correlation between E' and Vo(2)max (r = 0.41, p = 0.024). However, no correlation was found between conventional two-dimensional, Doppler indices, and proBNP and Vo(2)max). Of all the echocardiographic and clinical parameters assessed, E/E' ratio had the best correlation with exercise capacity (r - 0.47) and was the strongest independent predictor of Vo(2)max by multivariate analysis (p = 0.0106). CONCLUSIONS: DTI-derived indexes (E', E/E' ratio), an estimate of myocardial relaxation and LV filling pressures, correlate with exercise capacity in patients with ApHCM, suggesting that abnormal diastolic function may be a factor limiting exercise capacity.  相似文献   

7.
BACKGROUND: Experimental evidence indicates that magnesium sulfate may have potential cardioprotective properties as an adjunct to coronary reperfusion. The present study was designed to examine the hypothesis that magnesium might have beneficial effects on left ventricular (LV) function and coronary microvascular function in patients with acute myocardial infarction (AMI). METHODS AND RESULTS: The study population of 180 consecutive patients with a first AMI (anterior or inferior) underwent successful primary coronary intervention. Patients were randomized to treatment with either intravenous magnesium (magnesium group, n=89) or normal saline (control group, n=91). Pre-discharge left ventriculograms were used to assess LV ejection fraction (LVEF), regional wall motion (RWM) within the infarct-zone and LV end-diastolic volume index. The Doppler guidewire was used to assess coronary flow velocity reserve (CFVR) as an index of coronary microvascular function. Magnesium group subjects showed significantly better LV systolic function (LVEF 63+/-9% vs 55+/-13%, p<0.001; RWM: -1.01+/-1.29 SD/chord vs -1.65+/-1.11 SD/chord, p=0.004), significantly smaller LV end-diastolic volume index (63+/-17 ml/m(2) vs 76+/-20 ml/m(2), p<0.001), and significantly higher CFVR (2.95+/-0.76 vs 2.50+/-0.99, p=0.023) than controls. CONCLUSION: Magnesium sulfate as an adjunct to primary coronary intervention shows favorable functional outcomes in patients with AMI.  相似文献   

8.
BACKGROUND: Mitral regurgitation (MR) is known as one of the most frequent causes of heart failure and sudden death. In spite of increasing prevalence of MR, there have been no available data on cardiac determinants of exercise capacity in patients with chronic MR. HYPOTHESIS: This study aimed to investigate cardiac determinants of exercise capacity in patients with chronic MR. METHODS: We consecutively enrolled 32 patients (11 men, mean age: 44 +/- 14 years) who had greater than moderate MR with normal left ventricular (LV) systolic function (LV ejection fraction >50%). Conventional echocardiographic indices and parameters measured by Doppler tissue imaging at septal side of mitral annulus were obtained before exercise. Mitral regurgitation fraction, forward stroke volume, pulmonary venous flow velocities, and systolic pulmonary artery pressure (sPAP) were also obtained with standard methods. RESULTS: Left ventricular ejection fraction was 61 +/- 6% and MR fraction was 48 +/- 13%. All patients finished a symptom-limited treadmill exercise test with a peak heart rate of >85% of predicted maximum heart rate. Mean exercise time was 9.95 +/- 2.17 min, corresponding to 11 +/- 2 metabolic equivalents. Among pre-exercise echocardiographic variables, only early diastolic mitral annulus velocity (E') and pulmonary venous reversal flow velocity (PVa) showed a significant correlation with exercise time (r = 0.44, p = 0.011, and r = -0.40, p = 0.040, respectively), which persisted after multivariate analysis (p = 0.011 and 0.038, respectively). Other parameters such as systolic mitral annulus velocity, resting and postexercise sPAP, forward stroke volume, LV size, LV ejection fraction, left atrial size, and regurgitant fraction showed no significant correlation. CONCLUSIONS: Left ventricular diastolic function is an important determinant of exercise capacity in patients with chronic MR. Both E' and PVa, accepted surrogate estimates for LV diastolic function, may be useful for identifying patients with chronic MR and with poor exercise capacity.  相似文献   

9.
BACKGROUND: The relation between remodeling and left ventricular (LV) diastolic function has not yet been fully investigated. The aim of this study was to determine whether early assessment of Doppler-derived mitral deceleration time (DT), a measure of LV compliance and filling, may predict progressive LV dilation after acute myocardial infarction (AMI). METHODS AND RESULTS: Fifty-one patients (aged 61+/-11 years; 6 women) with anterior AMI successfully treated with direct coronary angioplasty underwent 2-dimensional and Doppler echocardiographic examinations within 24 hours of admission, at days 3, 7, and 30 and 6 months after the index infarction. Mitral flow velocities were obtained from the apical 4-chamber view with pulsed Doppler. End-diastolic volume index (EDVI) and end-systolic volume index (ESVI) were calculated with the Simpson's rule algorithm. Patients were divided according to the DT duration assessed at day 3 in 2 groups: group 1 (n=33) with DT >130 ms and group 2 (n=18) with DT 相似文献   

10.
AIMS: Impaired diastolic function is responsible for many of the clinical features of hypertrophic cardiomyopathy. In patients with hypertrophic obstructive cardiomyopathy (HOCM) whose symptoms are refractory to medical therapy, alcohol septal ablation (ASA) reduces left ventricular (LV) outflow tract gradient, with short-term improvement in LV diastolic function. Little is known about the longer term impact of ASA on diastolic function. METHODS AND RESULTS: We evaluated LV diastolic function at baseline and 1- and 2-year follow-up after successful ASA. In 30 patients (58+/-15 years, 22 men) who underwent successful ASA, New York Heart Association class was lower at 1-year follow-up compared with baseline (3.0+/-0.5 to 1.5+/-0.7; P<0.0001). LV outflow tract gradient (76+/-37 to 19+/-12; P<0.0001), interventricular septal thickness (19+/-2 to 14+/-2; P<0.0001), and left atrial volume (26+/-5 to 20+/-4; P<0.0001) were decreased. Significant improvement in E-wave deceleration time, isovolumic relaxation time, early diastolic mitral lateral annular velocity (E'), mitral inflow propagation velocity (V(p)), ratio of transmitral early LV filling velocity (E) to early diastolic Doppler tissue imaging of the mitral annulus (E/E'), and E/V(p) were observed at 1 year following successful ASA. These changes persisted in the subset cohort (n=21) for whom 2-year data were available. CONCLUSION: Successful ASA for HOCM leads to significant and sustained improvement in echocardiographic measures of diastolic function, which may contribute to improved functional status after successful ASA.  相似文献   

11.
About 15% of patients with myotonic dystrophy (MD) die of ventricular arrhythmias, but few have documented left ventricular (LV) dysfunction and heart failure. This study prospectively evaluated a group of patients with MD without known heart failure to assess whether there is subclinical impairment of LV contractility using conventional 2-dimensional echocardiography and tissue Doppler imaging, and to correlate any abnormalities found with the degree of neurologic severity and cytosine-thymine-guanine trinucleotide repeat length. Twenty-two patients with MD without known heart failure were evaluated and compared with 22 healthy, age-matched controls. The patients with MD and control subjects did not differ with respect to LV ejection fraction (60 +/- 5% vs 60 +/- 4%, respectively, p = 0.86). However, peak systolic velocities were significantly lower in subjects with MD compared with controls in the basal lateral (6.1 +/- 2.6 vs 8.2 +/- 2.0 cm/s, p <0.005), basal septal (5.0 +/- 1.1 vs 6.3 +/- 1.1 cm/s, p <0.0003), and mitral annulus-lateral segments (7.6 +/- 1.9 vs 9.2 +/- 1.9 cm/s, p = 0.007). Mean LV velocities were also lower in subjects with MD (6.2 +/- 1.3 vs 7.5 +/- 1.1 cm/s, p <0.002). In subjects with MD, the peak systolic velocities correlated inversely with neurologic severity (r = -0.51, p = 0.014) but not with trinucleotide repeat length. In conclusion, patients with MD without known heart failure were found to have reduced myocardial tissue velocities; the degree of velocity reduction correlated with their neurologic severity.  相似文献   

12.
An exaggerated increase in systolic blood pressure prolongs myocardial relaxation and increases left ventricular (LV) chamber stiffness, resulting in an increase in LV filling pressure. We hypothesize that patients with a marked hypertensive response to exercise (HRE) have LV diastolic dysfunction leading to exercise intolerance, even in the absence of resting hypertension. We recruited 129 subjects (age 63+/-9 years, 64% male) with a preserved ejection fraction and a negative stress test. HRE was evaluated at the end of a 6-min exercise test using the modified Bruce protocol. Patients were categorized into three groups: a group without HRE and without resting hypertension (control group; n=30), a group with HRE but without resting hypertension (HRE group; n=25), and a group with both HRE and resting hypertension (HTN group; n=74). Conventional Doppler and tissue Doppler imaging were performed at rest. After 6-min exercise tests, systolic blood pressure increased in the HRE and HTN groups, compared with the control group (226+/-17 mmHg, 226+/-17 mmHg, and 180+/-15 mmHg, respectively, p<0.001). There were no significant differences in LV ejection fraction, LV end-diastolic diameter, and early mitral inflow velocity among the three groups. However, early diastolic mitral annular velocity (E') was significantly lower and the ratio of early diastolic mitral inflow velocity (E) to E' (E/E') was significantly higher in patients of the HRE and HTN groups compared to controls (E': 5.9+/-1.6 cm/s, 5.9+/-1.7 cm/s, 8.0+/-1.9 cm/s, respectively, p<0.05). In conclusion, irrespective of the presence of resting hypertension, patients with hypertensive response to exercise had impaired LV longitudinal diastolic function and exercise intolerance.  相似文献   

13.
Jacques DC  Pinsky MR  Severyn D  Gorcsan J 《Chest》2004,126(6):1910-1918
STUDY OBJECTIVES: Early diastolic mitral annular velocity (E') by tissue Doppler echocardiography (TD) has been reported to be a load-independent index of left ventricular (LV) diastolic function, allowing the early diastolic mitral inflow velocity (E)/E' ratio to be used clinically to predict LV filling pressures. However, preload independence of E' has remained controversial, and E/E' may not consistently be predictive of LV filling pressures. Our objectives were to test the hypotheses that E' is affected by preload, and that alterations of preload, afterload, and contractility also affect E/E'. DESIGN, INTERVENTIONS, AND MEASUREMENTS: An open-chest dog model was used (n = 8). High-fidelity pressure and conductance catheters were used for pressure-volume relations, and E' was obtained by pulsed TD from the apical four-chamber view. Changes in preload and afterload were induced by vena caval and partial aortic occlusions, respectively. Data were collected during control phase and during infusions of dobutamine and esmolol to alter contractility. RESULTS: E' was consistently and significantly associated with acute decreases in LV end-diastolic pressure in each dog (n = 200 beats; r = 0.93 +/- 0.06 [mean +/- SD]). Similar results occurred with dobutamine and esmolol infusions. This preload sensitivity was reflected in E/E', which was inversely (rather than directly) correlated with LV diastolic pressure (r = - 0.67). E/E' was less affected by preload when diastolic dysfunction was induced by sustained partial aortic occlusion (time constant of relaxation increased from 46 +/- 19 to 53 +/- 21 ms, p < 0.001). CONCLUSIONS: E' was significantly influenced by preload with preserved LV function and low filling pressures (< 12 mm Hg); accordingly, E/E' was less predictive of LV filling pressures in this scenario. E/E' was more predictive of LV filling pressures in the presence of diastolic dysfunction.  相似文献   

14.
Peak early diastolic left ventricular (LV) filling rate has been used as an index of LV diastolic function. However, it is known to be affected by LV size. Peak early diastolic transmitral flow velocity measured by pulsed Doppler echocardiography has also been proposed as a noninvasive method of assessing LV diastolic function. To determine if peak early diastolic mitral flow velocity also is influenced by LV size, 20 normal neonates (age 2 days) and 21 normal adults (mean age 38 years) were studied using pulsed Doppler echocardiography to measure mitral flow velocity and M-mode echocardiography to estimate LV end-diastolic volume and mitral valvular area. Peak early diastolic LV filling rate was calculated by multiplying peak early diastolic mitral flow velocity by mitral valvular area. Adults had significantly larger LV end-diastolic volumes (mean +/- standard deviation 108 +/- 25 vs 7 +/- 3 ml) and higher peak early diastolic LV filling rates (305 +/- 75 vs 29 +/- 10 ml/s) than neonates (both p less than 0.001). However, no significant difference was found in peak early diastolic mitral flow velocity between adults and neonates (61 +/- 10 vs 58 +/- 11 cm/s). These data suggest that peak early diastolic mitral flow velocity is independent of LV size. Since peak LV filling rate is equal to the product of peak mitral flow velocity and mitral valvular area, the correlation between peak early diastolic LV filling rate and LV size is probably due to differences in mitral valvular area rather than differences in peak mitral flow velocity.  相似文献   

15.
BACKGROUND: Recently, two new indexes based on the ratio of transmitral early diastolic velocity (E) to tissue Doppler imaging (TDI), and early diastolic velocity of mitral annulus (E') and E to propagation velocity (Vp) have been proposed to predict left ventricular (LV) filling pressures. However, little is known about the comparative value of these two indexes. METHODS: We studied 71 consecutive patients referred for coronary angiography (mean age +/- SD, 65 + 11 years; 21 patients with LV ejection fraction [EF] < 50%). Complete Doppler echocardiographic examination including TDI and Vp measurements and direct measurement of LV end-diastolic pressure (LVEDP) were performed simultaneously in the catheterization laboratory. LV filling pressures were considered elevated when LVEDP was > or = 15 mm Hg. RESULTS: The correlation coefficients between E/E' and E/Vp and LVEDP were 0.68 (p = 0.01) and 0.54 (p = 0.01), respectively, in the overall population. The correlations were better in patients with low LV EF (< 50%) [0.8 (p = 0.01) and 0.77(p = 0.01)] and poor in patients with normal LV EF (0.57 [p = 0.05] and 0.41 [not significant]), respectively. Moreover, Vp measurements had higher interobserver variability compared to E' (14% vs 7%). The cutoff values for both indexes giving the best sensitivity and specificity in identifying LVEDP > or = 15 mm Hg were 9 for (E/E') and 2 for (E/Vp). CONCLUSION: Both E/E' and E/Vp can be used for the evaluation of LV filling pressures. However, the sensitivity of these indexes, especially E/Vp, is hampered by EF. E/E' has a lower variability than Vp and should be preferred for estimation of filling pressures especially in patients with EF > 50%.  相似文献   

16.
The quantification of left ventricular (LV) volumes and assessment of their relation to systolic and diastolic dysfunction, infarct size and anatomic location were performed in 54 patients with a first acute myocardial infarction (AMI). Blood pool radionuclide angiography was used to assess LV end-diastolic, end-systolic, and stroke volume indexes, ejection fraction and peak diastolic filling rate. Infarct size was estimated from plasma MB creatine kinase activity. Substantial LV dilation occurred within the initial 24 hours of AMI. The peak diastolic filling rate was low, even in those patients with a normal ejection fraction. In comparison with inferior AMI (n = 25), patients with anterior AMI (n = 29) had a larger end-diastolic volume index (105 +/- 8 vs 81 +/- 4 ml/m2, p less than 0.01) and end-systolic volume index (64 +/- 7 vs 37 +/- 4 ml/m2, p less than 0.001), but similar stroke volume index (41 +/- 3 vs 43 +/- 2 ml/m2, difference not significant). No significant relation was noted between infarct size estimated by MB creatine kinase and any volumetric index. On repeat study (day 10 after AMI), end-diastolic and end-systolic volume indexes increased further (p less than 0.05 vs day 1) but ejection fraction and peak diastolic filling rate were unchanged. It was concluded that: (1) LV dilation occurs within hours of AMI in both inferior and anterior AMI, but is more marked in the latter; (2) significant LV diastolic dysfunction is the rule, even in patients with preserved LV systolic function; and (3) LV dilation is an early compensatory mechanism that maintains normal stroke volume, even in patients with severely reduced LV function.  相似文献   

17.
Background: The mechanics of the complex left ventricular (LV) myocardial fiber architecture may accurately be assessed by speckle tracking echocardiography (STE). The role of STE to assess LV mechanical dysfunction in the setting of ST segment elevation myocardial infarction (AMI) is still poorly studied. Patients and Methods: 29 consecutive patients (55 ± 13 years) presenting with AMI underwent STE within 72 hours of admission. Reperfusion was achieved with thrombolysis in 15 patients and with primary percutaneous coronary intervention in 14. LV rotational and torsion data were registered during peak systole. Standard Doppler data included LV ejection fraction (EF), mitral inflow deceleration time (DT), and conventional E/A ratio. E/E' ratio (mitral inflow E velocity/tissue Doppler E velocity) was calculated as a marker of LV filling pressure. Twelve subjects with clinically indicated but negative dobutamine stress echocardiogram served as Controls. Results: Peak systolic torsion was not only significantly lower in AMI compared with Controls (13.3 ± 7.6 vs. 21.8 ± 6.1; P < 0.01), it was also lower in subjects with LVEF <40% (5.0 ± 2.9) compared with those who had LVEF >40% (10.6 ± 6.6; P < 0.02). Torsion had a modest but significantly positive linear relation (R = 0.6; P < 0.05) with DT, not with E/E' or LVEF. Conclusion: LV systolic torsion is decreased in AMI and more markedly decreased in patients with LVEF <40%. The most significant linear relationship between DT and torsion may possibly indicate that the LV mechanical dysfunction is also associated with altered filling dynamics. (Echocardiography 2010;27:45-49)  相似文献   

18.
Nonalcoholic fatty liver disease (NAFLD) is linked to the metabolic syndrome. The aim of the present study is to determine the effect of the metabolic syndrome on left ventricular (LV) geometry and function using as a model patients with NAFLD. Thirty-eight patients with NAFLD, less than 55 years of age and with a normal exercise test, were compared with an age and sex-matched control group. Patients with diabetes mellitus, hypertension, and body mass index>40 were excluded. A complete echocardiographic study including tissue Doppler imaging (TDI) was performed. The following parameters were assessed by echo Doppler: peak velocities of early (E) and late (A) diastolic filling, E/A ratio, flow propagation velocity (Vp). Using TDI early diastolic velocity (E'), and systolic velocity (S') of mitral annulus were obtained. The patients with NAFLD had a significantly higher body mass index (31.4+/-5 vs. 26.4+/-4 kg/m, P=0.01), higher glucose (100.6+/-13 vs. 83.0+/-10 mg/dL, P=0.01), and triglyceride levels (126.5+/-44 vs. 206.5+/-67 mg/dL, P<0.001). Increased thickness of the intraventricular septum, posterior wall (11.03+/-2.2 vs. 8.9+/-2.9 mm, P=0.001; 8.5+/-1.7 vs. 9.7+/-2.3 mm, P=0.04), and larger LV mass and LV mass/height (160.7+/-58.7 vs.115.3+/-35.4 g, P=0.001 and 92.6+/-29.5 vs. 69.2+/-19.8 g/m, P=0.001, respectively) were found in NAFLD group. LV systolic function was similar in both groups. Patients with NAFLD had a lower E (73.6+/-11.0 vs. 86.4+/-20.0 cm/s, P<0.006) and E/A ratio (1.0+/-0.3 vs. 1.76+/-0.8 P<0.0001). Moreover, the Vp and the E' on TDI were significantly lower compared with the control group (49.0+/-9.7 vs. 74.7+/-18.4 cm/s, P<0.0001 and 10.3+/-2.0 vs. 13.8+/-1.7 cm/s, P<0.0001, respectively). On multivariate analysis the E' on TDI was the only independent parameter associated with NAFLD. In conclusion, patients with NAFLD in the absence of morbid obesity, hypertension, and diabetes have mildly altered LV geometry and early features of left ventricular diastolic dysfunction. Early diastolic velocity on TDI was found to be the only index that could identify the patients with NAFLD and metabolic syndrome.  相似文献   

19.
The effects of reperfusion on left ventricular (LV) function and volume were studied in patients with evolving acute myocardial infarction (AMI). We analyzed the LV ejection fraction and volume in patients who had been admitted within 24 h of the onset of their first AMI with culprit lesion of #6, #7 and #1 (American Heart Association classification). Sixty-five patients (Re group) received successful reperfusion therapy within 6 h after the AMI. The other 60 patients (Oc group), who were admitted from 6 to 24 h after the AMI, received conservative therapy. Patients with re-obstruction of the culprit lesion after reperfusion therapy were excluded from the Re group. Patients with spontaneous recanalization following conservative therapy were excluded from the Oc group. The LV ejection fraction (LVEF), LV end-systolic volume index (LVESVI), and LV end-diastolic volume index (LVEDVI) were measured using a modified Dodge's formula by left ventriculography performed 4 weeks after the AMI. LVEF in the Re group was significantly greater than in the Oc group (57 +/- 12 vs 49 +/- 11%) (mean +/- SD, p less than 0.01). LVESVI in the Re group was significantly smaller than in the Oc group (30 +/- 13 vs 38 +/- 16 ml/m2, p less than 0.01). Although LVEDVI was not significantly different between the 2 groups, in patients with a responsible coronary lesion of segment #6, LVEDVI in the Re group was significantly smaller than in the Oc group (67 +/- 14 vs 77 +/- 18 ml/m2, p less than 0.05). Although LVEF and LV volume correlated in both groups, the correlation was weak (r = 0.40-0.42), suggesting that LV volume was not dependent solely on LV functional recovery. The incidence of ventricular aneurysm in the Re group was significantly lower than in the Oc group (15.4 vs 45.0%, p less than 0.01). Multivariate analysis selected reperfusion of the responsible coronary artery as one of the factors significantly associated with a reduction of LVEDVI, LVESVI, an improvement of LVEF, and a decrease in the rate of aneurysm formation. In summary, our results indicated that reperfusion improved EF, reduced LV volume, and decreased the rate of aneurysm formation as compared to non-reperfusion, which suggests that reperfusion therapy is beneficial for both functional recovery and ventricular remodeling.  相似文献   

20.
Left atrial (LA) enlargement is an indicator of chronic elevation in left ventricular (LV) end-diastolic pressure as well as diastolic dysfunction. There is a lack of data on the significance of LA volume in the pediatric population. The objective of this study was to elucidate the relation between LA volume and diastolic dysfunction, clinical symptoms, and exercise capacity in young patients with hypertrophic cardiomyopathy. All patients aged <20 years with obstructive hypertrophic cardiomyopathy who underwent evaluation at the Mayo Clinic from 2002 to 2006 were retrospectively identified. Reviews of the LA volume index and other traditional diastolic Doppler echocardiographic parameters, as well as clinical data, were performed. A total of 88 patients (66 male) were studied. The median age at evaluation was 14 years. The mean LA volume index was 39 +/- 19 ml/m(2). Additional echocardiographic parameters included a mean LV outflow gradient of 55 +/- 51 mm Hg, a mean E/E' ratio of 14.0 +/- 7.6, and a mean maximal septal wall thickness of 23 +/- 9 mm. On univariate linear regression analysis, LA volume index had an excellent correlation with diastolic dysfunction grade (p <0.001, r(2) = 0.6), LV outflow tract gradient, mitral E/E', and the degree of mitral regurgitation. LA volume index was also positively associated with symptom score (p = 0.005) and maximal oxygen consumption on exercise test (n = 22; p = 0.01). On multivariate analysis, LA volume index was related to diastolic dysfunction grade (p <0.001) and mean mitral regurgitation grade (p = 0.05). In conclusion, this study demonstrates the potential clinical importance of LA volume index in pediatric hypertrophic cardiomyopathy as a marker of the severity of underlying diastolic dysfunction, symptom score, and decreased exercise capacity. LA volume index has significant diagnostic and prognostic value in these patients.  相似文献   

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