Myocardial performance index in pediatric patients after cardiac transplantation.

BACKGROUND: Myocardial performance index (MPI) has been shown to be a reliable indicator of ventricular performance. This study determined MPI values in pediatric patients after cardiac transplantation without endomyocardial rejection. METHODS: MPI was determined in 41 pediatric patients after cardiac transplantation, without evidence of microscopic rejection, and in 31 pediatric control subjects. RESULTS: MPI in the transplantation group (0.41 +/- 0.12) was higher than in the control group (0.31 +/- 0.09; P =.0003). Isovolumic relaxation time and isovolumic relaxation time/ejection time were higher in the transplant group (55 +/- 20 milliseconds and 0.22 +/- 0.07, respectively) compared with the control group (41 +/- 10 milliseconds and 0.16 +/- 0.06, respectively; P =.0002). Isovolumic contraction time and isovolumic contraction time/ejection time were similar in the transplant group (48 +/- 23 milliseconds and 0.19 +/- 0.09, respectively) and control group (43 +/- 21 milliseconds and 0.16 +/- 0.08, respectively; P = not significant). CONCLUSIONS: Pediatric patients after cardiac transplantation without endomyocardial rejection have a higher MPI compared with a normative pediatric control population. The difference appears to be related to abnormal diastolic function.     

Effect of the isolated left bundle branch block on systolic and diastolic functions of left ventricle.

BACKGROUND: We planned this study to evaluate the effects of left bundle branch block (LBBB) on systolic and diastolic functions of left ventricle (LV) that have not previously been investigated in detail. MATERIAL AND METHODS: Forty-five cases diagnosed as isolated LBBB according to the standard electrocardiographic criteria (group I, mean age: 60 +/- 12 years) were taken as the case group and 65 cases with normal conduction system (group II, mean age 58 +/- 14 years) were taken as the control group. Echocardiography was performed to all patients and coronary angiography was performed to 21 patients in group I and 35 patients in group II. In addition to standard systolic and diastolic function parameters, isovolumetric relaxation time (IRT), isovolumetric contraction time (ICT), and ejection time (ET) were measured by echocardiography, and the myocardial performance index (MPI) [(IRT+ICT)/ET] was calculated. LV end-diastolic pressure was calculated for the patients undergoing coronary angiography. RESULTS: In group I, LV end-systolic diameter was greater (3.1 +/- 0.4 cm vs 2.8 +/- 0.4 cm, P <.001) and ejection fraction was lower (64% +/- 6% vs 68% +/- 6%, P <.001) than those of group II. Rapid filling deceleration time and rate was markedly different in group I (respectively, 133 +/- 50 ms vs 166 +/- 24 ms, P <.001; 608 +/- 291 cm/s(2) vs 383 +/- 116 cm/s(2), P <.001). In addition, it was found that LBBB caused shortening of LV diastolic period and ET markedly (respectively, 347 +/- 116 ms vs 394 +/- 106 ms, P =.03; 255 +/- 40 ms vs 294 +/- 21 ms, P <.001) and prolongation of IRT and ICT (respectively; 124 +/- 36 ms vs 91 +/- 16 ms, 96 +/- 35 ms vs 38 +/- 9 ms, P <.001). The MPI was predominantly higher in group I (0.89 +/- 0.29 vs 0.40 +/- 0.06, P <.001). Invasively determined LV end-diastolic pressure was found higher in group I (14 +/- 3 mm Hg vs 10 +/- 3 mm Hg, P <.001). CONCLUSION: A marked elevation of the LV MPI and end-diastolic pressure, parallel to changes of conventional echocardiographic parameters, in patients with isolated LBBB points out that LBBB causes marked deterioration on LV systolic and diastolic functions.     

定量组织速度成像技术测定心肌功能指数对心衰患者左心功能的评价

目的 应用定量组织速度成像技术(QTVI)研究心力衰竭(CHF)患者时间间期并计算心肌功能指数( MPI),以探讨其应用价值.方法 选择心衰患者(心衰组)及健康者(正常组)各30例,在QTVI条件下,分别显示二尖瓣瓣环处室间隔及左室各壁6个位点运动曲线 .分别测算6个位点的时间间期及局部MPI,并取6个位点局部MPI的均值作为左心室整体MPI .结果 与正常组比较,心衰组二尖瓣环处室间隔及左室各壁6个位点的等容收缩时间(ICT)和等容舒张时间(IRT)延长(P＜0.01),射血时间(ET)缩短(P＜ 0.05).心衰组整体及局部MPI均明显延长(P＜0.01).结论 应用时间间期及MPI可以快速、无创、敏感地评价心衰患者的左心功能.     

A perspective on atrioventricular delay optimization in patients with a dual chamber pacemaker

Atrioventricular delay (AVD) is critical in patients with DDD pacemakers (PM). Echo/Doppler evaluation of AVD providing the longest left ventricular filling time (FT) or the highest cardiac output (CO) is used for AVD optimization. Recently myocardial performance index (MPI) has been shown to improve by optimizing AVD. The aim was to compare the CO, FT, MPI derived optimal AVD, and to analyze systolic and diastolic performance at every optimal AVD. Twenty-five patients, 16 men 68 +/- 11 years, ejection fraction >or= 50%, with a DDD PM for third-degree AV block, without other major cardiomyopathies, underwent echo/Doppler AVD optimization. CO, FT, and MPI derived optimal AVDs were identified as the AVDs providing the highest CO, the longest FT, and the minimum MPI, respectively. Isovolumic contraction and relaxation time (ICT, IRT), ejection time (ET), ICT/ET, and IRT/ET ratios were also evaluated at every optimal AVD. CO, FT, and MPI derived optimal AVDs were significantly different (148 +/- 36 ms, 116 +/- 34 ms, and 127 +/- 33 ms, respectively). ICT/ET was similar at CO, FT, and MPI derived optimal AVD (0.22 +/- 0.10, 0.23 +/- 0.11, and 0.21 +/- 0.10, respectively). IRT/ET ratio was similar at FT and MPI derived optimal AVDs (0.34 +/- 0.15 and 0.33 +/- 0.15, respectively) and significantly shorter (P < 0.02) than at CO derived optimal AVD (0.40 +/- 0.15). Different methods indicate different optimal AVDs. However analysis of systolic and diastolic performance shows that different AVDs result in similar systolic or diastolic performance. At MPI optimized AVD, a high CO combined with the most advantageous conditions of both isovolumic contraction and relaxation phases is achieved.     

Gestational-age-adjusted reference values for the modified myocardial performance index for evaluation of fetal left cardiac function.

OBJECTIVE: It has been shown that the modified myocardial performance index (Mod-MPI) is associated with higher reproducibility than conventional MPI because it uses mitral and aortic valve 'clicks' to calculate each time period. We aimed to construct normal reference values for the Mod-MPI after 19 weeks' gestation. METHODS: The Mod-MPI was calculated in the left ventricle of 557 normal fetuses at 19-39 weeks' gestation. The isovolumetric contraction time (ICT), isovolumetric relaxation time (IRT) and ejection time (ET) were measured using the Doppler signals (clicks) of the opening and closing of the mitral and aortic valves as landmarks. Mod-MPI was calculated as (ICT + IRT)/ET. RESULTS: Throughout gestation, there was a small increase in the Mod-MPI (at 19 weeks it was 0.35 +/- 0.027 (mean +/- SD); at 39 weeks, 0.37 +/- 0.029; Mod-MPI = 0.33 + 0.001x gestational age (GA) (weeks), r(2) = 0.017). Of the three components, ICT remained constant, IRT increased (IRT = 0.028 + 2.52 x GA (weeks)), and ET slightly decreased (ET = 0.184 - 3.65 x GA (weeks)). Fetal heart rate (FHR) had no effect on the Mod-MPI, but the duration of IRT, ICT and ET decreased by 13-15% when FHR increased from 130 to 160 beats per minute. CONCLUSION: The GA-adjusted reference values for the Mod-MPI and the three time periods used for its calculation can be applied to fetal cardiac evaluation in the presence of pregnancy-associated complications.     

超声测量右室心肌功能指数评价急性肺栓塞治疗前后右室功能

目的应用超声心动图技术观察急性肺栓塞(APE)患者治疗前后右室舒缩功能的改变,探讨右室心肌功能指数(MPI)对APE患者右室功能的评估价值.方法利用超声对28例正常对照者及33例急性肺栓塞患者(其中大面积急性肺栓塞19例,非大面积急性肺栓塞14例)治疗前后的右室功能进行测定.结果急性肺栓塞患者三尖瓣E峰峰值速度(E)较对照组减低,右室等容收缩与等容舒张时间之和(ICT IRT)延长,右室心肌功能指数增高,大面积急性肺栓塞患者E峰减速时间(VEDT)延长,右室射血时间(ET)缩短;急性肺栓塞患者治疗后右室射血分数(EF)增高,(ICT IRT)缩短,右室心肌功能指数降低;大面积急性肺栓塞患者治疗后右心内径减小,肺动脉收缩压降低,VEDT缩短;非大面积急性肺栓塞患者治疗后右心内径、肺动脉收缩压及VEDT改变不明显.心肌功能指数与(ICT IRT)、EF、ET、VEDT、E间有相关关系(r分别为0.880、-0.513、-0.464、0.485、-0.462,P＜0.01).结论右室心肌功能指数是反映急性肺栓塞时右室功能变化的敏感指标.     

Evaluation of right ventricular dysfunction in patients with cardiac amyloidosis using Tei index.

BACKGROUND: Cardiac amyloidosis is an infiltrative disease causing predominant diastolic dysfunction and systolic dysfunction at its advanced stage. Right ventricular (RV) dysfunction is an independent predictor of poor prognosis in congestive heart failure and cardiomyopathies. However, the assessment of RV function is still technically difficult because of the complicated geometry of the RV. The recently proposed Tei index, obtained from the cardiac time interval analysis, allows noninvasive and quantitative estimation of global ventricular function without geometric evaluation. Therefore, this study was designed to assess RV function for patients with cardiac amyloidosis. METHODS: Study patients consisted of 30 consecutive patients with biopsy specimen-proven cardiac amyloidosis and 50 control subjects. Patients were classified as having early or advanced stage of cardiac amyloidosis on the basis of mean left ventricular wall thickness < 15 mm or >/= 15 mm. Tei index, defined as the sum of isovolumetric contraction and relaxation time divided by ejection time, was obtained from tricuspid and pulmonary Doppler flow velocity. RESULTS: RV Tei index was significantly increased for patients with cardiac amyloidosis (0.54 +/- 0.16 vs 0.28 +/- 0.05, amyloidosis vs control, P <.001). The incidences of abnormal RV isovolumetric contraction time, ejection time, isovolumetric relaxation time, and Tei index in all patients with cardiac amyloidosis were 63%, 43%, 73%, and 83%, respectively. The same incidences were 50%, 13%, 63%, and 75% in the early stage and 68%, 54%, 77%, and 86% in the advanced stage, respectively. CONCLUSION: Patients with cardiac amyloidosis frequently have RV dysfunction even in its early stage. Tei index allows simple, noninvasive, and nongeometric estimation of RV dysfunction in patients with cardiac amyloidosis.     

The influence of heart rate on the Doppler-derived myocardial performance index.

The Doppler-derived myocardial performance index (MPI), defined as the sum of isovolumetric contraction and relaxation durations divided by ejection time and reflecting both systolic and diastolic myocardial function, has been found to be related to morbidity and mortality in cardiac diseases. The MPI is easily obtained, reproducible, and has a narrow range in healthy subjects. The goal of this study was to study the influence of heart rate changes on the MPI. Thirty patients with sick sinus syndrome treated with a pacemaker with a right atrial lead were studied. The patients were paced at increasing rates from 50 to 100 bpm. The MPI increased on average 0.02 +/- 0.03 per 10-bpm increase in rate. The correlation between MPI and heart rate was weak (rho = 0.31, P <.01).     

A modified myocardial performance (Tei) index based on the use of valve clicks improves reproducibility of fetal left cardiac function assessment.

OBJECTIVE: To determine whether a modified myocardial performance index (Mod-MPI) involving assessment of the movements (clicks) of the mitral valve (MV) and aortic valve (AV), improves intra- and interobserver agreement as compared to the previously reported method for MPI estimation. METHODS: The Mod-MPI was recorded by two experienced operators in the left cardiac chambers of 25 normally grown fetuses using pulsed Doppler ultrasonography. The isovolumetric contraction time (ICT) was measured from the closure of the MV to the opening of the AV, the ejection time (ET) from the opening to the closure of the AV, and the isovolumetric relaxation time (IRT) from the closure of the AV to the opening of the MV. The Mod-MPI was calculated as (ICT + IRT)/ET. In addition, the MPI was estimated without using the valve clicks (F-MPI) as previously described. Intra- and interobserver agreement were then analyzed for both modalities. RESULTS: There was a significantly lower intra- and inter-observer variability in the estimation of all time periods with the Mod-MPI than with the F-MPI (ICT: intra-observer, 9.9% vs. 13.9%; interobserver 9.9% vs. 15.6%; IRT: intraobserver, 9.9% vs. 14.8%; interobserver 10.4% vs. 18.3%; and ET: intraobserver, 4.5% vs. 6.1%; interobserver 2.8% vs. 5.2%, respectively). Intraclass correlation coefficient (IntraCC) for the Mod-MPI was 0.8 (95% confidence interval (95% CI), 0.56-0.9) and for the F-MPI, the IntraCC was 0.62 (95% CI, 0.26-0.84); P = 0.01. Agreement between observers using the Mod-MPI showed a mean difference of 0.0 with 95% limits of agreement (LA) -0.09 (95% CI, -0.1 to -0.075) to 0.09 (95% CI, 0.075-0.1) and for the F-MPI the mean difference was -0.01 with 95% LA -0.26 (95% CI, -0.3 to -0.22) to 0.25 (95% CI, 0.21-0.29). CONCLUSION: Calculation of the Mod-MPI based on Doppler echoes of the MV and AV clicks is associated with a lower variation and better inter- and intraobserver agreement than the previously used method for fetal cardiac evaluation.     

Myocardial performance index in female rats with myocardial infarction: relationship with ventricular function parameters by Doppler echocardiography.

BACKGROUND: The aim of the study was to analyze the myocardial performance index (MPI), its relationship with the standard variables of systolic and diastolic functions, and the influence of time intervals in an experimental model of female rats with myocardial infarction (MI). METHODS: Forty-one Wistar female rats were submitted to surgery to induce MI. Six weeks later, Doppler echocardiography was performed to assess infarct size (IS,%), fractional area change (FAC,%), ejection fraction biplane Simpson (EF), E/A ratio of mitral inflow, MPI and its time intervals: isovolumetric contraction (IVCT, ms) and relaxation (IVRT, ms) times, and ejection time (ET, ms); MPI = IVCT + IVRT/ET. RESULTS: EF and FAC were progressively lower in rats with small, medium and large-size MI ( P < .001). E/A ratio was higher only in rats with large-size MI (6.25 +/- 2.69; P < .001). MPI was not different between control rats and small-size MI (0.37 +/- 0.03 vs 0.34 +/- 0.06, P = .87), but different between large and medium-size MI (0.69 +/- 0.08 vs 0.47 +/- 0.07; P < .001) and between these two compared to small-size MI. MPI correlated with IS (r = 0.85; P < .001), EF (r = -0.86; P < .001), FAC (r = -0.77; P < .001) and E/A ratio (r = 0.77; P < .001, non-linear). IVCT was longer in large size MI compared to medium-size MI (31.87 +/- 7.99 vs 15.92 +/- 5.88; P < .001) and correlated with IS (r = 0.85; P < .001) and MPI (r = 0.92; P < .001). ET was shorter only in large-size MI (81.07 +/- 7.23; P < .001), and correlated with IS (r = -0.70; P < .001) and MPI (r = -0.85; P < .001). IVRT was shorter only in large-size compared to medium-size MI (24.40 +/- 5.38 vs 29.69 +/- 5.92; P < .037), had borderline correlation with MPI (r = 0.34; P = .0534) and no correlation with IS (r = 0.26; p = 0.144). CONCLUSIONS: The MPI increased with IS, correlated inversely with systolic function parameters and had a non-linear relationship with diastolic function. These changes were due to the increase of IVCT and a decrease of ET, without significant influence of IVRT.     

Myocardial global performance index as a predictor of in-hospital cardiac events in patients with first myocardial infarction.

OBJECTIVE: We sought to assess the ability of a Doppler index of global myocardial performance (MPI), measured at entry, to predict inhospital cardiac events in a series of patients with first acute myocardial infarction (AMI). METHODS: A complete 2-dimensional and Doppler echocardiographic examination was performed within 24 hours of arrival at the coronary care department in 96 patients (81 men and 15 women; mean age 58 +/- 9 years) with first AMI. Patients were divided a posteriori into 2 groups according to their inhospital course: group 1 comprised 75 patients with an uneventful course and group 2 comprised 21 patients with a complicated inhospital course (death, heart failure, arrhythmias, or post-AMI angina). RESULTS: There were no significant differences between the 2 groups with regard to history of hypertension, diabetes mellitus, hypercholesterolemia, site and size of infarction, and conventional parameters of diastolic function. However, patients with complications were significantly older (63 +/- 10 vs 55 +/- 8 years, P =.005) and had higher wall-motion score index and left ventricular end-systolic volume compared with patients without events (1.84 +/- 0.27 vs 1.52 +/- 0.30, P =.001; and 66 +/- 29 vs 47 +/- 21 mL, P =.009, respectively), whereas the ejection fraction was reduced (40 +/- 10% vs 52 +/- 10%, P =.0001). The mean value of the MPI was significantly higher in patients with cardiac events than in those without events (0.65 +/- 0.20 vs 0.43 +/- 0.16, P =.0001). A MPI >/= 0.47 showed a sensitivity of 90% and specificity of 68% for identifying patients with events, on the basis of the receiver operator curve. In a multivariable model, the MPI at admission remained independently predictive of inhospital cardiac events (odds ratio 15.6, 95% confidence interval 2.4-99, P =.003). CONCLUSION: These data suggest that in the acute phase of AMI, the MPI measured at entry may be useful to predict which patients are at high risk for inhospital cardiac events.     

Evaluation of myocardial function using tissue Doppler imaging in children with moderate scorpion envenomation

Context. Scorpion envenomation is an important public health problem. It can cause life-threatening complications such as respiratory, neurological and cardiovascular compromise. Systemic envenoming signs and mortality rates are dramatically higher in children. Objective. The objective of this study was to evaluate myocardial function using pulsed tissue Doppler imaging in patients with moderate scorpion envenomation. Materials and methods. The study was conducted from July to October 2009 in the South-East Anatolia region of Turkey. The study population consisted of 30 children with moderate scorpion envenomation and 30 age- and sex-matched normal controls. Severe and mild envenomations were excluded. In addition to echocardiographic examination, pulsed tissue Doppler imaging was performed. Results. The average age was 7.6 ± 4.3 years in patients and 7.9 ± 3.2 years in controls (p value, 0.77). The mean heart rate was 114 ± 19 beats/min (range, 72–164) in patients and 95 ± 14 beats/min (range, 72–127) in controls (p < 0.01). Sinus tachycardia (> 120 beats/min in children) was detected in ten (33.3%) patients. Myocardial performance index (MPI) was obtained with tissue Doppler imaging. The ejection fraction, the fractional shortening, the MPI of the left ventricle, the MPI of the right ventricle, the left ventricular isovolumetric contraction time (ICT), the left ventricular isovolumetric relaxation time (IRT), the left ventricular ejection time, the right ventricular ICT, the right ventricular IRT and the right ventricular ejection were not statistically different between the patients and the controls (p > 0.05). Discussion. We did not detect any considerable myocardial involvement in the children presenting with moderate scorpion envenomation except for sinus tachycardia. If the patients are treated with antivenom within 4 h, patients with moderate scorpion envenomation may not develop cardiac dysfunction.     

急性心肌梗死患者Tei指数与左心室充盈模式及预后的关系

目的：探讨首次急性心肌梗死（AMI）患者Tei指数与左心室充盈模式及预后的关系。方法：对165例AMI患者的超声心动图参数进行检测。由二尖瓣及左心室流出道多普勒血流频谱曲线测定左心室等容舒张时间（IRT）、等容收缩时间（ICT）及左心室射血时间（ET）。左心室Tei指数＝（ICT+IRT）/ET。依据二尖瓣E波减速时间（EDT）和左心室舒张早期血流传播速度（Vp）将165例AMI患者分为正常充盈组、松弛性减低组、假性正常化组、限制性充盈组。应用Cox比例风险模型分析患者远期存活的风险预测。结果：165例AMI患者中,正常充盈43例、松弛性减低55例、假性正常化35例、限制性充盈32例。与正常充盈组比较,松弛性减低组、假性正常化组、限制性充盈组的Tei指数增大（P<0.05～0.01）;限制性充盈组的左心室舒张末期容积指数（EDVI）和收缩末期容积指数（ESVI）增加（P<0.05～0.01）。平均随访12（0～17）个月时,22例患者死亡。死亡组的Tei指数与生存组的Tei指数比较,差异有显著性意义（P<0.01）。Cox模型生存分析显示Tei指数≥0.6为死亡的独立危险因子（相对危险系数为3.997,P=0.028）。结论：AMI患者Tei指数与左心室充盈模式有关,能够反映左心室功能障碍的严重程度,是AMI后患者死亡的独立预测因子。     

Comparison of myocardial tissue Doppler with transmitral flow Doppler in left ventricular hypertrophy

We sought to determine the most useful echocardiographic measurements for assessment of diastolic function in patients with left ventricular hypertrophy (LVH) and normal systolic function. We compared myocardial Doppler velocities of the basal inferoposterior wall with mitral inflow pulsed wave Doppler velocities in 11 healthy volunteers (age, 36 +/- 6 years), 25 patients (age, 64 +/- 14 years) without LVH, and 37 patients (age, 67 +/- 14 years) with LVH and otherwise normal echocardiograms. The discriminatory measurements were myocardial A-wave duration (120 +/- 18 versus 98 +/- 20 and 92 +/- 12 ms, P <.0001), myocardial isovolumetric relaxation time (124 +/- 45 versus 95 +/- 48 and 78 +/- 25 ms, P =.0035), mitral A-wave velocity (0.98 +/- 0.37 versus 0.73 +/- 0.28 m/s and 0.61 +/- 0.22 m/s, P =.009), and mitral E-wave deceleration time (257 +/- 93 versus 201 +/- 85 ms and 184 +/- 83 ms, P =.015), which were significantly increased, and myocardial E-wave velocity (0.84 +/- 0.04 m/s versus 0.13 +/- 0.03 m/s and 0.14 +/- 0.03 m/s, P <.0001), which was significantly decreased, in patients with LVH compared with patients without LVH and normal volunteers, respectively. Left ventricular posterior wall thickness correlated with myocardial isovolumetric relaxation time (r = 0.52, P <.0001) and myocardial A-wave duration (r = 0.59, P <.0001), negatively with myocardial E wave (r = -0.43, P <.0001), and showed no correlation with mitral inflow parameters except mitral inflow A wave (r = 0.43, P =.002). On multivariate analysis using these variables, myocardial isovolumetric relaxation time (P =.0014) and A-wave duration (P =.001) were the only 2 variables that correlated with posterior wall thickness (multiple R = 0.71). In the presence of LVH and preserved left ventricular systolic function, myocardial relaxation time and velocities are more sensitive than mitral Doppler inflow parameters in detecting abnormal left ventricular relaxation.     

超声心动图评价缺血性心脏病左室功能

目的 采用心肌功能指数(myocardial performance index MPI)评估缺血性心脏病左心室功能的作用，探讨MPI的应用、影响因素及存在的不足。方法 缺血性心脏病患72例，健康40例，测量EF、E／A、IRT和MPI，并做比较分析。结果 缺血性心脏病患的E／A比值增高，IRT延长，EF明显下降，MPI明显增高。结论 MPI可以敏感地、全面地评估心脏的收缩和舒张功能。     

Index of myocardial performance is afterload dependent in the normal and abnormal left ventricle.

BACKGROUND: The index of myocardial performance (IMP) has been used as a prognostic systolic-diastolic index for patients with dilated cardiomyopathy and postmyocardial infarction. To date, systematic evaluation of afterload alteration (arterial pressure) on IMP has not been performed with normal or reduced left ventricular (LV) function. METHODS: We studied 15 mongrel dogs at baseline, after the induction of acute ischemic LV dysfunction, and with chronic LV dysfunction. Each dog was atrially paced, and the arterial pressure was reduced with nitroprusside (NTP) (>10 mm Hg) and increased with methoxamine (Methox) (>30 mm Hg) in random order. Hemodynamics and transmitral and transaortic pulsed Doppler were obtained. RESULTS: With normal LV function, there were no changes in IMP with NTP. Methox reduced IMP (0.51 +/- 0.12-0.45 +/- 0.12, P < .05) as a result of a shortened isovolumic contraction time (ICT). With acute LV dysfunction, IMP declined with NTP (0.74 +/- 0.19-0.65 +/- 0.17, P < .01) because of a shortened ICT and isovolumic relaxation time. Methox prolonged IMP (0.73 +/- 0.16-0.83 +/- 0.21, P < .05). With chronic LV dysfunction, NTP resulted in a reduced IMP (0.75 +/- 0.27-0.57 +/- 0.27, P < .01) as a result of a reduced ICT and isovolumic relaxation time and a prolonged LV ejection time associated with an increased LV ejection fraction. Methox increased IMP (0.72 +/- 0.26-1.31 +/- 0.43, P < .001) because of an increased ICT and isovolumic relaxation time and a reduced LV ejection time associated with a reduced LV ejection fraction. Forward stepwise regression indicated that both LV systolic pressure ( P = .0006) and LV ejection fraction ( P = .0222) were independent predictors of IMP. CONCLUSION: IMP is afterload dependent in the normal LV. IMP is afterload dependent with acute and chronic LV dysfunction by influencing the isovolumic indices and LV ejection time in opposite directions. Further systematic evaluation of IMP is needed if this index is to be useful as a prognostic indicator.     

Tei index 值与心功能不全程度之间的关系

我们用Ｄｏｐｐｌｅｒ法测得一种指标,即从房室瓣血流及心室身血血流频谱中,求得Ｔｅｉ ｉｎｄｅｘ值。并与临床心功能对比,讨论该指标的意义。结果该指数与心功能之间有一定关系,在人群间的重迭程度小,并且,指数与心率,二尖瓣返流程度无明显关系。     

肥厚型(左室)心肌病右室舒张功能的临床研究

目的：1．应用无创伤性频谱多普勒技术研究左室非对称性肥厚型心肌病(HCM)患者的右室舒张功能；2．探讨HCM患者右室舒张功能的可靠、准确的各项指标及其临床价值。方法：应用彩色多普勒超声诊断仪结合标I导心电图，对19例HCM患者及13例正常对照组人群的右室舒张功能进行研究。结果：1．HCM患者舒张早期E峰流速、E峰流速积分显著降低，舒张早期E峰减速时间明显延长，E峰减速度显著下降，E／A比值下降(P＜0．001)，舒张晚期A峰流速、A峰流速积分显著性增加（P＜0．01)；2．HCM思者的等容收缩时间(ICT)、等容舒张时间(IRT)均相对延长，右室射血时间(ET)明显缩短(P＜0．001)，二组的C指数之间亦存在显著性差异(P＜0．001)；3．C指数与ET、(IRT十ICT)间有显著性相关关系(r分别为0．81、0．66，P＜0．001)，C指数与IRT、ICT、ICT／ET间无相关关系。结论：1．HCM思考的右室舒张功能明显减退，右室等容舒张时间延长、舒张早期主动松弛和快速充盈速率降低、舒张晚期右房收缩功能增强，在频谱多普勒超声心动图上表现为IRT明显延长，E、ET、DC、E／A和EI／AI明显降低，A、AI和Td显著增高(P＜0．01～＜0．001)；2．HCM思考的右室收缩功能亦受到负面影响，在频谱多普勒超声心动图上表现为ICT显著延长，ET明显缩短(P＜0．001)；3．应用同时反映右室收缩和好张功能的Tei指数(C)的研究结果表明，正常对照组和HCM组间存在显著性差异(P＜0．001)。     

Female children and adolescents with type 1 diabetes have more pronounced early echocardiographic signs of diabetic cardiomyopathy

OBJECTIVE: This study was designed to assess whether children and adolescents with type 1 diabetes have early echocardiographic signs of subclinical cardiac dysfunction and whether sex, state of metabolic control, and diabetes duration are of influence. RESEARCH DESIGN AND METHODS: Systolic and diastolic blood pressure in supine and upright positions and echocardiographic parameters, including tissue Doppler measurements of the septal mitral annulus, were evaluated in 80 children and adolescents with stable type 1 diabetes and 52 age- and sex-matched control subjects. A possible correlation was examined for age, sex, HbA(1c), and diabetes duration with univariate and multivariate regression analysis. RESULTS: Female diabetic patients showed significantly larger left ventricular wall dimensions (left ventricular posterior wall in diastole 0.54 +/- 0.08 vs. 0.48 +/- 0.11 cm) and signs of significant diastolic filling abnormalities on conventional and tissue Doppler echocardiography (mitral valve-atrial contraction velocity 0.47 +/- 0.12 vs. 0.40 +/- 0.09 m/s; tricuspid valve-atrial contraction velocity 0.35 +/- 0.09 vs. 0.30 +/- 0.07 m/s; early filling velocity/myocardial velocity during early filling 7.15 +/- 1.47 vs. 6.17 +/- 1.07; isovolumetric relaxation time [IVRT] 66 +/- 8 vs. 58 +/- 8 ms) compared with female control subjects, suggesting delayed myocardial relaxation. Male diabetic patients only differed significantly from their control subjects for IVRT (66 +/- 9 vs. 59 +/- 8 ms). The measured parameters showed an expected correlation with age and BMI standard deviation scores in the control group. This correlation was significantly weaker in the diabetic population; only a weak influence was found for diabetes duration and glycosylated hemoglobin levels. CONCLUSIONS: Young diabetic patients already have significant changes in left ventricular dimensions and myocardial relaxation, with the girls clearly being more affected. Tissue Doppler proved to have additional value in the evaluation of ventricular filling in this population. Almost no correlation was found for diabetes duration and HbA(1c) with the cardiovascular changes.     

Serial Doppler echocardiographic assessment of left and right ventricular performance after a first myocardial infarction.

We sought to investigate the relation between left ventricular (LV) and right ventricular (RV) function assessed with the Doppler-derived myocardial performance index (MPI), to assess serial changes, and to investigate the prognostic value of biventricular assessment of cardiac function after a first myocardial infarction (MI). To do so, serial Doppler echocardiography was performed in 77 consecutive patients with a first MI. Right ventricular MPI correlated significantly with LV MPI (r = 0.51, P <.0001). In patients with echocardiographic signs of RV MI, the RV MPI was significantly higher (0.59 +/- 0.18 versus 0.44 +/- 0.19, P =.001), whereas no difference in LV MPI was seen (0.55 +/- 0.19 versus 0.56 +/- 0.13, P = not significant). Right ventricular MPI showed a rapid normalization during follow-up, whereas LV MPI did not decrease. During follow-up, 23 patients died of cardiac causes or were readmitted because of worsening heart failure. Multivariate Cox analysis indicated LV MPI (relative risk 4.9 [95% CI 1.8-13.5], P =.002) and RV MPI (relative risk 3.8 [1.3-17.0], P =.01) to be predictors of cardiac events. Thus the RV MPI is frequently abnormal after a first MI but normalizes rapidly on follow-up, and biventricular assessment of cardiac function may improve the prognostic accuracy compared with LV assessment alone.