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1.
Diagnosis of coronary artery disease (CAD) by exercise echocardiography is usually based on rest or exercise-induced regional wall-motion abnormalities. Mitral regurgitation (MR), left ventricular (LV) global systolic function, and LV inflow measurements can be assessed during exercise echocardiography; however, their diagnostic value has not been analyzed consistently. Treadmill exercise echocardiography and coronary angiography were performed in 120 patients (94 male, 26 female; mean age 61 +/- 10 years [+/- 1 SD]) to evaluate known or suspected CAD. Positive exercise echocardiography was defined either as a rest- or exercise-induced regional wall-motion abnormalities. An abnormal response of LV ejection fraction (EF), LV volumes, MR (as assessed by color Doppler), and LV inflow pattern was defined as a fall in LVEF, a LV end-diastolic volume increase, a LV end-systolic volume increase, a new or increased MR, or a change from an impaired relaxation pattern (E < A) to a "pseudonormalized" pattern (E > A) from rest to exercise, respectively. CAD (> or = 50% luminal narrowing in at least one vessel) was found in 89 (74%) patients. EE-based regional wall-motion abnormality analysis was positive in 95 (79%) patients and negative in 25 (21%) patients. Feasible images for regional wall-motion abnormalities, LVEF and volumes, LV inflow, and MR measurements were acquired in 90% of patients. Regional wall-motion abnormality analysis and LVEF decrease provided the greatest sensitivities for CAD (94% and 75%, respectively), while the highest specificity was given by a new or increased MR (90%), the development of a pseudonormalized pattern (88%), and the appearance of angina (87%). A positive electrocardiogram (ECG) finding in patients with interpretable ECGs provided good sensitivity and specificity (67% and 85%, respectively). In conclusion, a complete rest and exercise Doppler echocardiography approach is feasible in most patients. Regional wall-motion abnormalities are the most accurate exercise echocardiography variable for diagnosing CAD, whereas exercise ECG remains a good test in patients with interpretable ECGs. Exercise echocardiography, exercise ECG, newly developed or increased MR, and change to a pseudonormalized LV inflow pattern are highly specific.  相似文献   

2.
To define the availability of Doppler echocardiography in evaluating left ventricular hemodynamic changes induced by some clinical findings of acute coronary insufficiency, we selected 12 patients with angina and 32 affected by acute myocardial infarction. Doppler echocardiography was performed at hospital admittance and during recovery time. Left ventricular contractility was defined on the systolic aortic flow spectrum by measuring the aortic velocity maximum, the time to peak/left ventricular ejection time ratio, and the cardiac output. During the first examination, left ventricular contractility significantly decreased in patients with angina and in those with acute myocardial infarction. After the acute phase, these parameters slightly improved. Left ventricular diastolic filling was evaluated in the transmitral flow. A decreased E-wave velocity and an increased late component (A wave) with inversion of the E/A wave ratio were found in patients with acute myocardial infarction during the first examination. This morphology inverts when the patients stabilize. On the contrary, this ratio stayed above one during and after angina. In this study, we also defined the usefulness of the color Doppler method in setting up criteria to identify some early morphological complications of acute myocardial infarction in 12 patients with acute infarction and a new systolic murmur. This technique showed an ischemic rupture of the ventricular septum in five cases and mitral regurgitation in seven. The color Doppler method has allowed us to obtain a semi-quantitative assessment of the mitral regurgitation and the location of the ventricular septal defect.  相似文献   

3.
To establish the normal limits for various pulsed Doppler echocardiographic indices of left ventricular diastolic function, 92 healthy volunteers aged from 5 to 75 years were prospectively studied. The influence of various variables including age, gender, body surface area, fractional shortening, and left ventricular mass on these parameters was also assessed. Mean (2SD) values for 15 direct and 11 derived parameters were analyzed from transmitral inflow velocity waveform. No statistically significant differences were observed between males and females for any of these parameters. On stepwise multivariate linear regression analysis, age was found to be an independent strong determinant (p less than 0.001) of peak velocity of early diastolic filling wave, area of atrial filling period, deceleration slope, normalized peak filling rate, and early filling fraction. There was a significant correlation between heart rate and time to peak early diastolic velocity, total diastolic time period, early diastolic period, atrial filling period, and atrial filling fraction. It was further observed that a significant correlation (p less than 0.001) persisted between both age and heart rate with area of early filling period, one-third filling area, one-half filling area, ratio of early to atrial peak velocity and area, atrial filling fraction, and one-third filling fraction. None of the parameters were found to correlate with fractional shortening or left ventricular mass. Thus an effort was made to establish normal limits for various Doppler-derived parameters in healthy volunteers for future comparison in diseased states.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

4.
AIM AND METHODS: The possibility of using multiplane transoesophageal echocardiography (TEE) and quantitative coronary angiography (QCA) in the diagnostics of stenotic atherosclerosis of the main coronary arteries in a comparative aspect were studied in 94 patients with coronary artery disease (men, mean age 52 +/- 7 years). Coronary arteries stenoses were calculated with Doppler echocardiography using a modified continuity equation: stenosis (%)=100 x(1-prestenotic VTI(d)/stenotic VTI(d)) where prestenotic VTI(d), (cm)=diastolic velocity integral in the prestenotic zone, and stenotic VTI(d), (cm)=in the trans-stenotic zone. RESULTS: High sensitivity and specificity of TEE in the diagnostics of stenotic and occlusive atherosclerosis of coronary arteries were revealed. They measured 88% and 98% for the left main coronary artery (LMCA), 97% and 67% for the left descending artery (LDA), 95% and 92% for the circumflex artery (CX), 83% and 97% for the right coronary artery (RCA), respectively. A high correlation was found between the results of TEE and QCA in the diagnostics of coronary stenoses which were made for the LMCA (r=0.82P <0.001), LDA (r=0.84, P<0.001), CX (r=0.85,P <0.001), and RCA (r=0.84, P<0.001). We developed Doppler echocardiography criteria for haemodynamically significant stenoses of coronary arteries (>50%) according to a peak diastolic velocity of the coronary blood flow, calculated as 1.4m.s(-1)for the LMCA, 0.9m.s(-1)for the LDA, and 1.1m.s(-1)for the CX. We determined Doppler echocardiography criteria of coronary arteries occlusions such as a 'break' of colour mapping, absence of Doppler spectrum and retrograde blood flow during late diastole. CONCLUSION: Transoesophageal Doppler evaluation of coronary blood flow with application of a modified continuity equation is an accurate, non-invasive method of coronary arteries stenoses diagnostics.  相似文献   

5.
In order to evaluate the effect of an increase in preload caused by contrast medium (Renografin-75) on Doppler echocardiographic indices of left ventricular diastolic properties, left ventricular pressure using a catheter tip micromanometer and pulsed-Doppler measurement of transmitral flow signals were measured simultaneously in 15 patients with coronary artery disease pre- and post-left ventricular angiography. After left ventricular angiography, changes in indices determined from left ventricular pressure were significant: left ventricular end-diastolic pressure increased from 17 +/- 2 mmHg to 24 +/- 2 mmHg (mean +/- SE) (P less than 0.001), maximum -dP/dt increased from 1,129 +/- 63 to 1,307 +/- 90 mmHg/sec (P less than 0.005), and time constant decreased from 73 +/- 2 to 67 +/- 1 msec (P less than 0.01). Changes in Doppler-derived indices were also significant: A/E ratio decreased from 0.99 +/- 0.08 to 0.81 +/- 0.07 (P less than 0.01), peak velocity of early diastolic filling increased from 0.61 +/- 0.03 to 0.79 +/- 0.03 M/sec (P less than 0.01), and deceleration rate increased from 3.1 +/- 0.2 to 4.6 +/- 0.2 M/sec 2 (P less than 0.01). Changes in Doppler echocardiographic indices (DR, acceleration half time, deceleration half time, and A/E ratio) were accompanied by changes in time constant and maximum -dP/dt after left ventricular angiography. However, the correlations between changes in hemodynamic indices and changes in Doppler echocardiographic indices were poor (r = 0.06 to 0.67).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

6.
The monitoring of aortic blood flow velocities by transcutaneous continuous-wave Doppler was performed in 45 patients to determine, non-invasively, the haemodynamic response to exercise in subsets of coronary patients during a multistage supine exercise tests. Group I consisted of 14 patients with ischaemia on effort (IE); group II, 12 patients with both IE and prior myocardial infarction (MI); group III, 19 patients with MI and no IE; there were also 12 normals. Peak flow velocity (PV) indices of cardiac output (CO), of peripheral resistance (PR) and of stroke work (SW) were measured every min. Resting CO was lower and PR higher in coronary patients than in normals. With exercise, for the same muscular work, CO increased less in IE patients (group I: y = 26.9 + 1.8 x cm sec-1; Group II: y = 21.9 + 1.8 x cm sec-1) than in MI (group III: y = 26.6 + 2.1 x cm s-1) and in normals (y = 35 + 2.7 x cm s-1) and PR decreased less. This suggested a more efficient distribution of CO towards working muscles. A shallower increase in SW was observed in all coronary patients in comparison with normals even if resting SW was significantly lower only in patients with MI (groups II and III). PV increased up to peak exercise only in group III, while it tended to plateau in ischaemic patients even earlier than IE occurred on the ECG.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

7.
AIMS: To study left ventricular mechanics of exercise with Doppler and tissue Doppler. METHODS AND RESULTS: Twenty-one males (mean age, 26; height, 184 cm; weight, 84 kg), exercised on a bicycle, with increasing workload, with oxygen uptake, Doppler flow and tissue Doppler recordings during exercise. There was correlation between peak systolic LVOT flow and annulus velocity; R=0.72, (p<0.001) and between peak mitral E flow and annulus E(a) velocity; R=0.68(p<0.001). Finally there was correlation between peak LVOT and mitral flow velocity; R=0.83(p<0.001) and peak systolic and early diastolic annulus velocity R=0.69(p<0.001). All intervals of the heart cycle decreased with RR-interval. There was a linear relation between diastolic filling and RR-interval, while ejection period was less increased with RR-intervals above 600 ms, and thus not a linear relationship. There was no change in E/E(a) ratio during exercise. CONCLUSIONS: Mechanism for increased filling as well as ejection during exercise seems to be increased contraction and relaxation velocity, with no evidence of Frank-Starling mechanism. Bazett's formula gives a better heart rate correction of LVET at high heart rates than Weissler's.  相似文献   

8.
冠状动脉病变程度对左室功能的影响   总被引:10,自引:0,他引:10  
目的 探讨冠心病患者冠状动脉病变程度与左室功能的关系。方法  30 6例选择性冠状动脉造影 ,193例冠状动脉造影证实冠心病患者按病变程度、范围及Gensini积分分组 ,测定左室射血分数、短轴缩短分数、舒张早期充盈峰及舒张晚期充盈峰的最大峰值速度 ,并计算E/A比值。结果 冠状动脉轻度、中度病变、单支病变及Gensini积分小于 2 0分时 ,左室收缩功能改变不明显 (P >0 .0 5 ) ,舒张功能出现减退 (P <0 .0 5或P<0 .0 1)。收缩功能减退与受累血管数量、病变程度重及Gensini积分高有明显相关性。结论 冠心病患者左室舒张功能减退常先于收缩功能减退 ,舒张功能的异常是冠心病心功能受累早期改变的敏感指标  相似文献   

9.
Doppler echocardiography provides the ability to measure blood flow velocities noninvasively. These blood flow velocities can be used to obtain powerful hemodynamic information about systolic contractility of the left ventricle, which in the past could only be determined from invasive cardiac catheterization or cumbersome pulse recordings. Volumetric flow rates can be measured using the hydraulic principle of flow through a rigid tube, providing a measurement of stroke volume and cardiac output. The rate of the left ventricular pressure rise derived from a mitral regurgitation velocity curve provides a nonejection phase index of systolic contractility. Acceleration time can be obtained from an ascending aortic velocity and is an indicator of maximum myocardial force. Systolic time intervals can now be quickly and accurately obtained from the standard Doppler tracings. These quantitative measurements of the status of the left ventricle are accurate, reproducible, and should be incorporated into the routine noninvasive assessment of patients with cardiac disease.  相似文献   

10.
102名健康中年人运动试验前后舒张功能的正常变异   总被引:1,自引:0,他引:1  
目的:观察健康中年人运动试验前后舒张功能的变化。方法:使用多普勒彩色超声心动图仪分别测量102名健康中年人静息时、运动试验后15min及60min的E峰最大流速(EPFV)、A峰最大流速(APFV)、EPFV/APFV(EK/A)比值、E峰减速时间(Edt)。结果:健康中年人运动试验后15min及60min EPFV、E/A比值、Edt与静息时相比均明显下降。APFV运动试验前后无差异。运动试验后15min E/A比值比静息时降低0.5以内。结论:健康中年人运动试验后舒张功能存在生理性下降,运动后15min的E/A比值较静息时明显降低,但应<0.5。  相似文献   

11.
Assessment of left ventricular (LV) diastolic filling pressure provides important information on the hemodynamic status in the general population. The aim of our study was to investigate the reliability of tissue Doppler imaging (TDI) in estimating left ventricular filling pressure in patients with coronary artery disease (CAD). We prospectively studied 32 consecutive CAD-patients, mean age 64 +/- 12 years, in sinus rhythm. All patients underwent cardiac catheterization and echocardiography within the same hour. Catheterization investigated pre-A-wave pressure (preA) and LV ejection fraction (LVEF). Echocardiographic LVEF was calculated using wall motion indexes (WMI) with segmental division of LV wall. The following Doppler parameters were assessed: (1) PW Doppler signals from the mitral inflow (E), (2) PW TDI of the mitral annulus (E'), thus allowing to obtain the mitral inflow to annulus ratio (E/E'). The best correlation between invasive and echocardiographic LVEF was observed using WMI (r = 0.91). The correlations between preA and E, E', and E/E' were significant (r = 0.36, r = 0.38, and r = 0.60, respectively). In patients with LVEF >50%, no correlation between E/E' and preA was found (r = 0.18, P = 0.44), whereas with LVEF <50%, this correlation was strong (r = 0.76, P < 0.001). In patients with myocardial infarction, the correlation between E/E' and preA was significant whatever the localization of myocardial infarction (r > 0.71, P < 0.05). ROC curve analysis identified an E/E'>9 to be the best cut-off value related to preA > 15 mmHg. We conclude that the mitral inflow-to-annulus ratio is a reliable method in CAD patients and allows determination of LV filling pressure when LVEF <50%.  相似文献   

12.
The purpose of this study was to assess altered left ventriculardiastolic filling by noninvasive means in patients with coronaryartery disease and normal systolic pump function. Mitral inflowvelocity was measured by pulsed Doppler, and left ventricularvolumes were obtained from cross-sectional echocardiographyat rest and during upright bicycle exercise. Peak and integratedearly and late diastolic filling velocities were calculatedfrom Doppler-derived time-velocity curves. Studies were performedin normal subjects (group I, n = 8) and in patients with angiographicallyproven coronary artery disease (Group II, n = 18). The ejectionfraction was not significantly different in group II as comparedto group I (group 1, 60 ± 7%; group II, 55 ± 11%).During exercise, ejection fraction increased significantly ingroup I by 7·6%, but did not increase in group II. Inall cases, diastolic filling showed a biphasic pattern. At rest,the major part of diastolic filling occurred during early diastole:the ratio of early filling velocity integral (E) to the latefilling velocity integral (L) was significantly greater in groupI than in group II (group I, 1·74 ± 37; groupII, 1·19 ±·3, P<0·001). Duringexercise, early diastolic filling was unchanged in normal subjectsbut decreased in patients, with a significant decrease in E/Lindex of 34% (P < 0·001). Thus, pulsed Doppler echocardiography provides a useful methodfor assessing noninvasively exercise-induced changes in leftventricular diastolic filling dynamics in patients with coronaryartery disease.  相似文献   

13.
BACKGROUND: Mitral annulus systolic velocity measured by Doppler tissue imaging (DTI) offers an alternate method for assessment of global left ventricular systolic function. However, there has been no study correlating mitral annulus systolic time intervals with left ventricular ejection fraction (LVEF). METHODS: Patients with angina pectoris (AP, 16 cases) and prior myocardial infarction (MI, 34 cases) were studied by pulsed DTI. Sixteen age-matched normal subjects served as controls. The septum, lateral, anterior, and inferior walls of the mitral annulus were selected for DTI sampling. Time to peak of the systolic mitral annular wave (TS) and regional preejection period (PEP) were measured. RESULTS: PEP and TS were significantly longer in the MI group than that in the control and the AP groups. Both PEP and TS at all the annular sites and their two-site averages had significantly negative correlations with LVEF (r =-0.62 to -0.68 and -0.49 to -0.62; P < 0.001, respectively). CONCLUSION: PEP and TS as measured by pulsed DTI may be promising indexes for the quantitative assessment of global left ventricular systolic dysfunction in patients with coronary artery disease.  相似文献   

14.
15.
AIMS: Although peak exercise echocardiography has been reported for both bicycle and treadmill exercise and has shown higher sensitivity than post-exercise imaging, little is known about its utility for identifying multivessel involvement. We sought to compare feasibility and accuracy of peak treadmill exercise echocardiography vs post-exercise echocardiography for identification of multivessel coronary artery disease and to assess its incremental value when combined with clinical and exercise test variables. METHODS AND RESULTS: The study group included 335 patients (228 men; mean (+/- SD) age 60 +/- 11 years). Two hundred and seventy-nine patients were included on the basis of having had an exercise echocardiography and a coronary angiography within 4 months of the exercise test. To avoid bias to coronary angiography, a subgroup of 56 consecutive non-diabetic patients referred for exercise echocardiography with pretest probability of coronary artery disease <10% and had atypical chest pain or were asymptomatic were also included and considered as having no coronary artery disease. Multivessel coronary artery disease (> or = 50% diameter stenosis in >1 vessel) was confirmed in 170 patients, whereas 165 patients were considered to have one-vessel coronary artery disease or no coronary lesions. Positive exercise echocardiography was defined as ischaemia or necrosis in at least two coronary territories. Post-exercise images were acquired within 125 s after exercise (49 +/- 15). Mean heart rate (bpm) was 139 +/- 19 at peak vs 117 +/- 22 at post-exercise imaging (P<0.001). Interpretable peak and post-exercise images were obtained for all patients. Sensitivity for predicting multivessel disease was higher with peak than with post-exercise imaging (79 vs 55%, P<0.001), with lower specificity (79 vs 88%, P<0.05). Predictive positive value was similar (80 vs 83%). Negative predictive value was again higher with peak imaging (78 vs 66%, P<0.01). Total accuracy was not different (79 vs 72%). A stepwise logistic regression analysis identified peak exercise echocardiography positivity for multivessel coronary artery disease as the strongest independent predictor of multivessel disease (odds ratio (OR): 7.36); also significant were male gender (OR: 4.22), diabetes mellitus (OR: 4.28), previous myocardial infarction (OR: 3.12) and increment of product heart rate x blood pressure (OR: 1.00). CONCLUSIONS: Peak treadmill exercise echocardiography is technically feasible and has higher sensitivity and negative predictive value for predicting multivessel disease than post-treadmill exercise echocardiography. This method adds independent and incremental values to clinical and exercise variables for the diagnosis of multivessel coronary artery disease. Therefore, in the clinical setting, peak exercise echocardiography should be performed to diagnose multivessel coronary artery disease.  相似文献   

16.
Pulmonary vein Doppler spectrum is highly load-dependent and thus has been used to estimate left ventricular (LV) filling pressure. However, the impact of LV function on pulmonary vein Doppler spectrum remains obscure because only load-sensitive indices were studied previously. In the present study, measurements of the pulmonary vein Doppler spectrum were correlated with load-insensitive LV systolic (end-systolic elastance [Ees]) and diastolic (relaxation time constant [tau] and beta coefficient of the end-diastolic pressure volume relationship) function indices obtained from an invasive catheterization study nonsimultaneously. The peak velocity, velocity time integral, and duration of systolic forward spectrum were significantly correlated with Ees (r = 0.35, r = 0.36, and r = 0.41, respectively;P < 0.05). The pulmonary vein diastolic velocity time integral (PVDVTI) and duration of the diastolic forward spectrum were significantly correlated with Ees (r = 0.51 and r = 0.57, respectively;P < 0.01). PVDVTI was correlated with tau and the end-diastolic pressure-volume relationship (EDPVR) (r = 0.42 and r = 0.40 respectively,P < 0.05). On the other hand, the systolic fraction of the forward spectrum was significantly correlated with ejection fraction (for peak velocity,r = 0.63, P < 0.01; for velocity time integral,r = 0.37, P < 0.05) but not with Ees, and the diastolic fraction of the forward spectrum was significantly correlated with minimum pressure derivative over time (for peak velocity,r = 0.48, P < 0.05; for velocity time integral,r = 0.44, P < 0.05, respectively) but not with tau or EDPVR. In summary, the systolic and diastolic components of the pulmonary vein Doppler spectrum are affected variably by LV systolic and diastolic function, independent of the loading condition. The systolic and diastolic fraction of pulmonary vein Doppler spectrum appears to depend more on the loading condition than the LV systolic or diastolic function.  相似文献   

17.
It is uncertain whether dobutamine echocardiography is a better test than exercise electrocardiography for the detection of coronary disease in patients who can exercise. We compared the hemodynamics, sensitivity, and specificity of these tests in 24 patients, 16 with coronary disease and 8 controls. The tests were performed within six weeks of one another and were interpreted without knowledge of other clinical data. The exercise electrocardiogram was considered abnormal if the patient developed one mm of ST-segment depression, while the dobutamine test (up to 40 micrograms/kg/min) was considered abnormal if the patient developed ST-segment depression or a left ventricular wall motion abnormality. Exercise testing resulted in a higher heart rate (145 +/- 29 vs. 110 +/- 24, p less than 0.001) and blood pressure (176 +/- 31 vs. 148 +/- 24, p less than 0.001). Dobutamine testing was 25% more sensitive than exercise testing (94 vs. 69%, 95% confidence interval for difference is 0 to 50%, p = 0.09), while exercise testing was 38% more specific (88 vs. 50%, 95% confidence interval for difference is -3 to 79%, p = 0.14). We conclude that exercise results in a higher heart rate and blood pressure than dobutamine infusion. Differences in sensitivity and specificity are inconclusive, but indicate that the sensitivity of exercise testing is, at best, equivalent to dobutamine testing, while any increase in specificity with dobutamine testing, compared with exercise testing, would not be clinically significant.  相似文献   

18.
BACKGROUND: A limitation of exercise echocardiography (EE) is its semiquantitative approach in analyzing wall-motion abnormalities. However, pulsed-Doppler tissue imaging is capable of a systolic and diastolic regional quantitative assessment. METHODS: To investigate the feasibility of performing pulsed-Doppler tissue imaging sampling of the basal left ventricular (LV) septum during EE, we studied 105 consecutive patients (71 men, 34 women, aged 61 +/- 11 years). Harmonic two-dimensional (2-D) echocardiography was performed at rest and peak EE, whereas pulsed-Doppler tissue imaging was performed at rest and immediately after EE. Adequate recordings for peak systolic velocity (Vs) were possible in all patients, but peak early diastolic (Ve) and peak late diastolic (Va) velocities were possible in 78 (74%) patients. Positive 2-D echocardiography was considered as infarction or an ischemic response. RESULTS: Forty-five (43%) patients (Group 1) had wall-motion abnormalities involving the left anterior descending artery (LAD) territory (29 with ischemia, 11 with ischemia and necrosis, and 5 with necrosis), 21 (20%) (Group 2a) had wall-motion abnormalities involving the left circumflex (LCX) and/or the right coronary artery (RCA) territories, and 39 (37%) (Group 2b) had normal EE. Heart rate increased from 72 +/- 17 beats/min to 143 +/- 18 beats/min (P < 0.0001) and systolic blood pressure from 129 +/- 19 mmHg to 174 +/- 26 mmHg (P < 0.001). Coronary angiography was performed in 30 (29%) patients, 29 of whom had positive findings on EE. LAD or diagonal branch coronary artery disease (CAD) (> or = 50% luminal narrowing) was present in 22 patients, 10 of whom had proximal severe stenosis (> or = 70% luminal narrowing). Vs increase was significatively lower in Group 1 (40 +/- 35%, from 6.0 +/- 1.5 cm/sec to 8.1 +/- 2.2 cm/sec) than Group 2a (75 +/- 35%, from 6.3 +/- 1.4 cm/sec to 10.8 +/- 2.1 cm/sec, P < 0.0001) and Group 2b (64 +/- 27%, from 6.7 +/- 1.3 cm/sec to 10.9 +/- 2.0 cm/sec, P < 0.001). Ve was not different at rest and at postexercise between groups. Va was similar at rest but higher at postexercise in Group 2b than Group 1 (11.8 +/- 2.3 cm/sec vs 10.3 +/- 3.0 cm/sec, P < 0.05). Failure to achieve Vs > or = 9.5 cm/sec after exercise was found to be the more accurate limit to detect necrosis or ischemia in the LAD territory according to EE criteria (sensitivity 76%, specificity 78%). When analysis was limited to the 30 patients who underwent angiography, we found that the 10 patients with proximal severe LAD or diagonal branch stenosis showed blunted increases in Vs (increase 9.4 +/- 19%, from 6.5 +/- 1.2 cm/sec at rest to 7.4 +/- 1.7 cm/sec at post-EE; P = 0.17) in contrast to the 20 patients having moderate or nonsignificant stenosis (increase 31 +/- 20%, from 6.2 +/- 1.5 cm/sec at rest to 9.3 +/- 1.8 cm/sec at post-EE, P < 0.0001). A failure to increase Vs > or = 30% had a sensitivity of 90% and a specificity of 80% in detecting proximal severe stenosis. CONCLUSION: Pulsed-Doppler tissue imaging sampling of the LV septum is feasible technically during EE and allows quantification of the regional response. This method may be accurate for detecting proximal severe stenosis in vessels supplying the LAD territory.  相似文献   

19.
AIMS: The early effect of percutaneous transluminal coronary angioplasty on left ventricular diastolic dysfunction was investigated with the aid of new Doppler echocardiographic applications. METHODS: Thirty patients with isolated severe left anterior descending coronary artery stenosis were included. All patients exhibited abnormal diastolic function demonstrated by prolonged isovolumic relaxation and deceleration time and decreased E/A ratio. New Doppler indexes included the flow propagation velocity of E wave, E and A waves' transit time to the left ventricular outflow tract, the ratio of these transit times in addition to the traditional isovolumic relaxation time, mitral deceleration time, and early and late transmitral peak flow velocities. All measurements were performed within 4 h before angioplasty and repeated within 24 h after the procedure. RESULTS: After angioplasty none of these parameters, except the A-wave transit time, were changed significantly. The A-wave transit time increased significantly from 57 +/- 5 ms to 78 +/- 7 ms within 24 h after successful angioplasty. The ratio of E- and A-wave transit time decreased significantly due to this significant increase in A-wave transit time. CONCLUSION: In this study, early improvement of Doppler index of left ventricular diastolic compliance is demonstrated after successful angioplasty.  相似文献   

20.
BACKGROUND: Patients with known or suspected coronary disease are often investigated to facilitate risk assessment. We sought to examine the cost-effectiveness of strategies based on exercise echocardiography and exercise electrocardiography. METHODS AND RESULTS: We studied 7656 patients undergoing exercise testing; of whom half underwent exercise echocardiography. Risk was defined with the Duke treadmill score for those undergoing exercise electrocardiography alone, and by the extent of ischaemia by exercise echocardiography. Cox proportional hazards models, risk adjusted for pretest likelihood of coronary artery disease, were used to estimate time to cardiac death or myocardial infarction. Costs (including diagnostic and revascularisation procedures, hospitalisations, and events) were calculated, inflation-corrected to year 2000 using Medicare trust fund rates and discounted at a rate of 5%. A decision model was employed to assess the marginal cost effectiveness (cost/life year saved) of exercise echo compared with exercise electrocardiography. Exercise echocardiography identified more patients as low-risk (51% vs 24%, p<0.001), and fewer as intermediate- (27% vs 51%, p<0.001) and high-risk (22% vs 4%); survival was greater in low- and intermediate-risk and less in high-risk patients. Although initial procedural costs and revascularisation costs (in intermediate-high risk patients) were greater, exercise echocardiography was associated with a greater incremental life expectancy (0.2 years) and a lower use of additional diagnostic procedures when compared with exercise electrocardiography (especially in lower risk patients). Using decision analysis, exercise echocardiography ( in 2615/life year saved) was more cost effective than exercise electrocardiography. CONCLUSION: Exercise echocardiography may enhance cost-effectiveness for the detection and management of at risk patients with known or suspected coronary disease.  相似文献   

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