定量组织速度成像测量二尖瓣环运动速度

目的　应用定量组织速度成像测量二尖瓣环运动速度评价扩张型心肌病患者左室舒张功能。方法　定量组织速度成像测量 14例正常人和 14例扩张型心肌病患者二尖瓣环 6个节段 (后间隔和侧壁、前间隔和后壁、前壁和下壁 )舒张早期峰值速度Ve、左房收缩期峰值速度Va ,计算Ve Va ;多普勒超声心动图测量二尖瓣口血流快速充盈速度E峰、左房收缩充盈速度A峰 ,计算E A值。结果　正常人和扩张型心肌病患者两组间E A无显著统计学差异 ,而扩张型心肌病组二尖瓣环平均Ve Va、平均Ve较正常组显著减低 (Ve Va :0 .89± 0 .11vs 1.76± 0 .76,P =0 .0 0 1;Ve :-4 .79± 2 .2 2vs -8.42± 2 .2 7,P<0 .0 0 0 1) ;正常组中二尖瓣环平均Ve Va与E A显著相关 (r =0 .63 ,P =0 .0 0 8) ,而扩张型心肌病组二尖瓣环平均Ve Va与E A无显著相关。结论　扩张型心肌病患者二尖瓣口血流频谱表现为假性正常化 ,定量组织速度成像测量二尖瓣环运动速度可准确评价其左室舒张功能。     

Tortuosity of coronary arteries: an indicator for impaired left ventricular relaxation?

Objective To investigate the relationship between coronary tortuosity and impaired left ventricular relaxation. Methods One hundred and four subjects who underwent coronary angiography were included in the study. Left anterior descending, left circumflex, and right coronary arteries were traced. Tortuosity was identified by the finding of ≥3 bends (defined as ≥45° change in vessel direction) along main trunk of at least one artery. Study population were divided into tortuosity (n = 54) and no tortuosity (n = 50) groups. Subjects were all submitted to pulsed-wave Doppler and two-dimensional echocardiographic examination to assess left ventricular functions. Results For subjects with tortuosity, early transmitral inflow (E) velocity was lower, late transmitral inflow (A) velocity was higher, E/A ratio was smaller compared with subjects without tortuosity (P < 0.001). Subjects with tortuosity had longer deceleration time of E velocity (DT) and isovolumic relaxation time (IVRT) than did subjects without tortuosity (P < 0.001). End-diastolic interventricular septal and left ventricular posterior wall thicknesses were greater in subjects with tortuosity than those without tortuosity (P = 0.01 and P = 0.005). There was an inverse correlation between total number of arteries with tortuosity and E/A ratio (r = −0.750, P < 0.001). Total number of arteries with tortuosity displayed correlations with DT (r = 0.723, P < 0.001) and IVRT (r = 0.703, P < 0.001). Conclusions This study depicts that coronary tortuosity is associated with impaired left ventricular relaxation.Thus, coronary tortuosity might be an indicator of impaired left ventricular relaxation.     

Significance of echocardiographic atrioventricular plane displacement for the evaluation of left ventricular filling and end-diastolic pressure in patients with coronary artery disease

The aim of this study is to assess the left ventricular filling and estimate the end-diastolic pressure of the left ventricle in patients with coronary artery disease (CAD) by echocardiographic measurement of the atrioventricular plane displacement (AVPD). In 101 patients (mean age 59 ±12 years) with CAD, a complete transthoracic echocardiographic study was performed, just prior to cardiac catheterization. The AVPD was recorded by Mmode echocardiography, from apical four and two chamber views. The recordings were obtained at four sites, corresponding to the septal, lateral, anterior and inferior walls of the left ventricle. The mean AVPD resulting from atrial systole (At), the mean total (T) diastolic AVPD, the ratio At/T(%) and the ratio of mitral annulus excursion during early and late diastole [(T-At)/At] were calculated. Firty-two age-matched healthy subjects served as control group. Both At and At/T were significantly greater in patients with CAD than in the controls (6.06 ±0.94 vs 5.53 ±0.55 mm, p<0.01 and 43.4 ±5.9% vs 33.49 ±4.45%, p<0.001 respectively). The ratio [(T-At)/At] correlated with the E/A ratio of transmitral flow, both in healthy subjects (r=0.850, p<0.001) and in patients with CAD (r = 0.722, p<0.001). Correlation also existed both in patients with segmental wall motion abnormality (SWMA) (r = 0.691, p<0.001) and in patients with SWMA (r=0.818, p<0.001). In patients with CAD, At/T further correlated with the left ventricular end-diastolic pressure (r=0.517, p<0.001). In patients with SWMA and in patients without, a correlation was also found (r=0.516, p<0.001 and r=0.566, p<0.001 respectively). In conclusion, AVPD measured by echocardiography can be used as a simple noninvasive parameter to evaluate left ventricular filling in patients with CAD and for the gross estimation of end-diastolic pressure of left ventricle.     

The spectrum of left ventricular filling in severe aortic stenosis

To assess left ventricular diastolic filling in valvular aortic stenosis, pulsed Doppler echocardiography was used prospectively in 35 patients with severe aortic stenosis (valve area < 1 cm²) and in 38 age-matched normal subjects. Twenty-seven patients had a normal left ventricular systolic function at rest (ejection fraction > 0.50) and a normal or only slightly increased mean pulmonary capillary wedge pressure (mean 11±4 mm Hg). Eight patients had a poor left ventricular systolic function (ejection fraction: 0.28±0.10) and an elevated mean pulmonary capillary wedge pressure (mean: 36±9 mm Hg). The Doppler derived filling parameters were correlated with hemodynamic data, left ventricular wall thickness derived from M-mode echocardiograms, heart rate and atrio-ventricular (A-V) conduction delay using stepwise multiple correlation. The data of this study suggest that left ventricular filling is significantly impaired in patients with severe aortic stenosis and left ventricular hypertrophy with an increase in late diastolic (A-wave) velocity, an increase in the A/E ratio, a decrease in the first one-half filling fraction and a prolongation of early diastolic deceleration time. These changes in filling hemodynamics are associated with alterations in mean pulmonary capillary wedge pressure, left ventricular wall thickness, heart rate and A-V conduction delay. When heart failure develops as a result of impaired left ventricular systolic function, an increase in left atrial filling pressure is associated with a shift of left ventricular filling towards early diastole with a ‘normalisation’ of the transmitral flow velocity curve. In extreme cases, a progression towards a ‘restrictive’ filling pattern is found with a marked shortening of the left ventricular early diastolic deceleration time. In the presence of high filling pressures, increased left atrial driving pressure (derived from the mean pulmonary capillary wedge pressure) is associated with changes in the left ventricular filling pattern irrespective of the presence and the degree of myocardial hypertrophy.     

Assessment of left ventricular diastolic function from mitral annulus motion,a comparison with pulsed Doppler measurements in patients with heart failure

Summary. Mitral and pulmonary venous flow velocity recordings are often used for the assessment of left ventricular diastolic function. These curves are, however, also influenced by other factors. To investigate whether mitral annulus motion carries additional information in this context, mitral annulus motion was compared to Doppler registrations of mitral and pulmonary flow velocities in 38 patients with heart failure (NYHA II—III) after myocardial infarction. Patients with an increased atrial contribution to mitral annulus motion (> 57%, n= 12) had a higher mitral late-to-early flow velocity ratio (A/E) and pulmonary systolic to diastolic filling ratio (<0–01). Patients with atrial displacement above average for the group (? 5.1 mm, n= 19) had a higher mitral AVE ratio and pulmonary systolic to diastolic filling ratio than patients with a lower than average atrial component (P < 0.05). There was a significant correlation between a/T ratio and A/E ratio (r= 0.61, P < 0.001) and between pulmonary flow and transmitral flow (= 0.76, P < 0.001). We conclude that an increased atrial displacement of the mitral annulus is a frequent finding in patients with signs of left ventricular relaxation abnormality. There is a significant correlation between a/T ratio and A/E ratio but the information contained in the two indices are not identical.     

Relationship between the tricuspid annular plane systolic excursion and right and left ventricular function in critically ill patients

Objective Echocardiographic recording of the tricuspid annular plane systolic excursion (TAPSE) has been recommended for assessing right ventricular function in cardiac patients. The ability of TAPSE to reflect right ventricular function at baseline and to monitor acute changes in right ventricular function was tested in critically ill patients. Design Prospective study. Setting A 24-bed medical intensive care unit. Patients Eighty-six patients admitted for acute respiratory failure, circulatory failure, or coma. Interventions In 40 patients, the examination was repeated after volume expansion (n = 15), passive leg raising (n = 5), or dobutamine infusion (n = 20). Measurements and results The right ventricular fractional area change, TAPSE, the left ventricular ejection fraction, and the ratio of right to left ventricular end-diastolic area were measured using Doppler echocardiography. In the overall population, TAPSE (19 ± 5 mm) was positively related to left ventricular ejection fraction (r ² = 0.31, p < 0.001) and right ventricular fractional area change and was negatively related to age and to the ratio of right to left ventricular end-diastolic area. Multivariate analysis indicated that only left ventricular ejection fraction and agewere independently related toTAPSE (multiple r ² = 0.36, p < 0.001). Following dynamic interventions, the changes in TAPSE were linearly related to changes in left ventricular ejection fraction (r ² = 0.65, p < 0.01) but notto changes in the right ventricular fractional area change. Conclusions Unexpectedly, TAPSE was more strongly related to left ventricular ejection fraction than to indices of right ventricular function in critically ill patients. The potential interest of TAPSE as a dynamic marker of left ventricular systolic function deserves further study.     

Systolic heart failure and cardiac resynchronization therapy: a focus on diastole

Conflicting data exist about the effects of cardiac resynchronization therapy (CRT) on diastolic function (DF). Aim of the study was to assess if and how CRT affects DF in systolic heart failure patients. We also investigated potential relations between CRT-induced left ventricular changes and the composite clinical endpoint of progressive heart failure and cardiac death over 3 years follow-up. 119 CRT patients underwent clinical evaluation and echocardiography before CRT and 4 months later. DF was quantified by transmitral velocities [E/A waves, deceleration time (DT), E/DT], early diastolic mitral annulus velocity (E′), E/E′ ratio and 2-D speckle tracking strain rate during isovolumetric relaxation (IVR, SRivr). End-diastolic pressure–volume relationship (EDPVR) was also assessed noninvasively using a single-beat method. Overall stiffness was quantified by ventricular stiffness (K_lv) normalized to end-diastolic volume (EDV). New York Heart Association class improved at 4 months (from 2.7 ± 0.7 to 1.9 ± 0.6, p < 0.001) as did ventricular filling (E/DT from 0.48 ± 0.29 to 0.39 ± 0.31 cm/s², p = 0.01). In contrast, relaxation (E′, SRivr) and filling pressures (E/E′, E/SRivr) did not change. Slope of EDPVR did not change with CRT. Such finding, together with an unmodified Klv/EDV and a 7 ± 18 % reduction in EDV (p = 0.001), suggested reverse remodelling towards a smaller equilibrium volume. Finally, end-systolic LV volume decreased from 147 ± 59 to 125 ± 52 ml and ejection fraction increased from 0.26 ± 0.07 to 0.32 ± 0.09 (both p < 0.001). Using a Cox regression model we found that only changes (Δ) in diastolic, but not systolic indexes, correlated with the composite clinical endpoint, with increments in ΔEDV20 and ΔE/DT, single or combined, greatly increasing risk of heart failure and/or cardiac death (p = 0.003). Ventricular reverse remodelling, together with improvement in ventricular filling, rather than improvements of systolic function, predict clinical prognosis long-term post-CRT.     

心肌功能综合指数评价慢性肺心病患者右室功能的临床研究

目的探讨心肌功能综合指数(MPI)评价慢性肺心病患者右心功能的临床价值.方法慢性肺心病患者40例,正常对照组50例,应用多普勒超声心动图检查,记录三尖瓣舒张期和右心室流出道收缩期脉冲多普勒血流频谱,测量MPI.结果①慢性肺心病患者等容舒张期时间及等容收缩期时间明显延长、射血时间明显缩短,导致MPI明显升高(0.94±0.33 vs 0.30±0.06,P<0.0001);②慢性肺心病组MPI与年龄、肺动脉收缩压呈正相关.结论 MPI是评价慢性肺心病患者右心功能的简便而准确的多普勒超声新指标.     

Transesophageal Doppler echocardiographic assessment of pulmonary venous flow pattern in subjects without cardiovascular disease

This study was designed to assess pulmonary venous flow dynamics using transesophageal Doppler echocardiography. Under general anesthesia, we studied 54 surgical patients with no history or physical evidence of cardiac disorders. In all patients pulmonary venous flow was easily identified by transesophageal color flow mapping. Pulmonary venous flow pattern, which was obtained clearly in 85% (4654) of patients by transesophageal pulsed Doppler echocardiography, was tri- or quadriphasic. The first wave, which was often biphasic in elderly patients, occurred during ventricular systole (S wave). The second wave occurred in diastole during the early ventricular filling phase of mitral flow (D wave). The third wave was reverse flow toward the pulmonary vein during atrial contraction (A wave). The following variables were measured: the peak flow velocities of each wave (PFVs, PFVd, PFVa), and the ratio of PFVs to PFVd (PFV(S/D)). The PFVd correlated with age (r=?0.56, P<0.001), indicating age-related decrease. The PFV(S/D) correlated with age (r=0.61, p<0.001), indicating age-related increase. These results would indicate that the contribution of pulmonary venous flow during diastole to total pulmonary venous flow decreases with age. Our data suggest that age-related diastolic dysfunction of the left ventricle would affect pulmonary venous flow dynamics and that left atrial storage volume during ventricular systole would increase with age.     

超声心动图评价血管紧张素受体拮抗剂对高血压病患者 左室舒张功能的影响

目的应用多普勒超声心动图评价血管紧张素II1型受体(AT1)拮抗剂对高血压病患者左室舒张功能的影响.方法分别于AT1拮抗剂(Losartan)服用前和服用12周后,对26例轻至中度原发性高血压病患者进行超声心动图检查.在心尖左心长轴切面上,用多普勒超声心动图测量二尖瓣口舒张早期峰值速度E、舒张晚期峰值速度A和E峰减速时间,并计算E/A比值;在左室长轴切面上,在二维超声心动图引导下用M型超声心动图测量舒张末期左室内径、室间隔和左室后壁厚度,并计算左室重量.结果服用Losartan 12周后,E/A比值(1.20±0.32)明显高于服用前(1.07±0.31,P＜0.0001),E峰减速时间从185±32 ms下降到164±29 ms(P=0.002);左室重量从220±53g减低为194±53g(P=0.003).结论AT1拮抗剂losartan具有改善高血压病患者左室舒张功能的作用.     

Association of carotid arterial distensibility with Doppler indices of left ventricular filling in 50-year-old subjects

Doppler indices of left ventricular diastolic filling are associated with various cardiac and extracardiac factors. Afterload is one of the extracardiac factors influencing left ventricular diastolic filling. The distensibility of the great arteries is one of the components of afterload. In this study, the relation between Doppler indices of left ventricular filling and the distensibility of the common carotid arteries was investigated. We studied 237 subjects at 50 years of age with Doppler echocardiography and ultrasound examination of the common carotid arteries. The following Doppler indices of left ventricular filling were studied: peak early diastolic velocity E-wave, peak atrial diastolic velocity A-wave and early to atrial peak velocity ratio, E/A. Carotid arterial characteristics were: distensibility coefficient, carotid arterial diameter change in systole and fractional change in the carotid arterial diameter. The relation between Doppler indices of left ventricular filling and carotid arterial characteristics was assessed by univariate and multivariate regression analysis. There was a significant univariate, positive association between E/A ratio and carotid arterial distensibility (r = 0·27, P<0·001), carotid arterial systolic diameter change (r = 0·19, P<0·005) and fractional change of the carotid arterial diameter (r = 0·20, P<0·005). In multivariate analysis, E/A ratio was independently associated with carotid arterial distensibility (P<0·005), after adjusting for heart rate, body mass index and gender. Decreased carotid arterial distensibility was associated with a reduction in E/A ratio, suggesting that arterial distensibility may have an effect on left ventricular diastolic filling or that changes in the arterial elastic properties are associated with corresponding structural changes in the left ventricle.     

声学定量技术对肥厚型心肌病患者左室舒张功能的评价

目的：应用声学定量（AQ）技术评价肥厚型心肌病（HCM）患者的左室舒张功能。方法：17例HCM患者和13例正常人进行了AQ检测。结果：与正常组相比,HCM患者左室心搏量和峰值排空率无显著性差异（P＞0. 05),左室快速充盈容量、快速充盈分、快速充盈期左室充盈容量与心房收缩期左室充盈容量的比值、峰值心房充盈率明显增高（P均＜0.05-0.001）;17例HCM患者中,二尖瓣血流频谱E／A＜1者占6例,左室舒张功能异常检出率为35.29％;而以AQ珠峰值快速 盈率与峰值心房充盈率比较即PRFR／PAFR＜1为标准,则左室佶功能异常检出率为58.82％（10／17）,二者联合对左室舒张功能异常检出率为82.35%（14／17）。结论：AQ技术为定量评价HCM患者的左室舒张功能提供了新的途径。     

Tissue Doppler echocardiography in evaluation of cardiac effects of subclinical hypothyroidism

Objective: Subclinical hypothyroidism (SH) is a mild form of thyroid failure, associated with initial signs of cardiovascular hypothyroidism. Tissue Doppler echocardiography (TDE) is a new and powerful method in evaluation of both regional and global systolic or diastolic ventricular function. We aimed to investigate the use of TDE in evaluation of cardiac effects of SH and affect of thyroid hormone replacement therapy (TRT) on tissue Doppler parameters of SH patients. Methods: Twenty-two patients who were diagnosed as SH and 22 healthy, age and sex-matched cases were included in the study. Conventional echocardiography and TDE were performed in all individuals. TRT was started in SH group. On the achievement of euthyroid state echocardiography were repeated. Results: Septal annulus relaxation time was significantly higher in SH group (82±21, 98±11 ms, p=0.024). Lateral annulus and myocardial relaxation times, precontraction/contraction ratios and precontraction times were also slightly higher. Septal lateral annulus and lateral myocardial relaxation times were decreased after TRT (98±11 vs. 81±12, p<0.001, 89±14 vs. 78±11, p=0.022, 90±16 vs. 80±14 ms, p=0.008, respectively). Precontraction times and precontraction/contraction ratios decreased after TRT but did not reach the significance level. There was a positive correlation between TSH and TDE relaxation times. Conclusions: TDE is a powerful tool in diagnosis and follow-up of SH patients and TRT inhibits adverse affects of SH on myocardium. Septal myocardium is the most affected region of left ventricle in SH. The relaxation time is the best criteria of cardiac involvement and monitoring the effect of TRT.     

Evaluation of cardiac function by echo-Doppler studies in critically ill patients

Measurements of stroke volume (SV) by echo-Doppler techniques (2D-echocardiography, continuous and pulsed Doppler) were compared to those obtained by thermodilution in 116 critically ill patients. The best correlation was obtained with pulsed Doppler positioned in the left ventricular (LV) outflow (r=0,78, p<0.001). In a subgroup of 12 patients who had LV ejection fraction < 60% and LV end-diastolic pressure > 15 mmHg, we also measured the peak aortic blood velocity (PABV) and acceleration (PABA) by continuous and pulsed Doppler as indexes of myocardial contractility before coronary artery bypass graft. When compared to healthy volunteers, these patients had decreased PABV and PABA, measured by continuous Doppler (91±16 vs 79±9 cm/s, p<0.05 and 913±202 vs 660±149 cm/s/s, p<0.05, respectively). These data therefore indicate that in critically ill patients pulsed Doppler placed in the LV outflow is an adequate echo-Doppler technique to measure SV, while continuous Doppler placed in the suprasternal notch can be used to assess LV performance.     

Strain and strain rate echocardiography for evaluation of right ventricular dysfunction in patients with idiopathic pulmonary arterial hypertension

Optimizing the non-invasive imaging of right ventricular (RV) function is of increasing interest for therapy monitoring and risk stratification in patients with idiopathic pulmonary hypertension (IPAH). Therefore, this study evaluated strain and strain rate echocardiography as a tool for comprehensive assessment of RV function and disease severity in IPAH patients. In 30 IPAH patients [WHO functional classes II–IV; mean pulmonary artery pressure (mPAP) 48.8 ± 12.5 mmHg; pulmonary vascular resistance (PVR) 7.9 ± 5.3 Wood units] and in 10 matched healthy control subjects’ two-dimensional echocardiography, 6-MWD and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels were obtained. In IPAH patients when compared with controls, RV systolic strain (−18.8 ± 4.3 vs. −34.5 ± 3.8%, p = 0.0016) and strain rate (−1.6 ± 0.6 vs. −2.7 ± 0.5 s⁻¹, p = 0.018) were significantly altered and correlated significantly with elevated NT-proBNP levels (r = 0.73 and r = 0.62; p < 0.001, respectively) and reduced 6-MWD (r = −0.76 and r = −0.81; p < 0.001). In IPAH patients, reduced strain correlated with both mPAP (r = 0.61, p = 0.01 for strain; and r = 0.55, p = 0.04 for strain rate, respectively), and PVR (r = 0.84, p < 0.001 for strain; and r = 0.67, p < 0.001 for strain rate, respectively). This study gives first comprehensive evidence that strain echocardiography allows accurate non-invasive assessment of RV function and disease severity in patients with IPAH.     

多普勒超声Tei指数估测单心室患者心功能的研究

目的评价多普勒超声Tei指数估测单心室患者心功能的价值.方法 46例单心室患者及80例正常儿童为研究对象,应用多普勒超声测量房室瓣及半月瓣的血流频谱,计算单心室患者的Tei指数,并与正常儿童心室Tei指数对比.结果正常儿童左心室Tei指数为0.30±0.08,右心室Tei指数为0.26±0.08.与正常人对比,单心室患者的射血时间缩短、等容收缩时间间期和等容舒张时间间期延长(P<0.05),Tei指数明显增高(0.55±0.13,P<0.001).结论 Tei指数不依赖心室的几何形态,可以用来估测单心室患者的心功能变化.     

Effect of the Mueller manoeuvre at different lung volumes on left ventricular performance in normal subjects

Summary. The effect of reduced intrathoracic pressure at different lung volumes on cardiac function was assessed by echocardiographic measurements of left ventricular size in normal subjects who performed the Mueller manoeuvre at two preselected lung volumes. At functional residual capacity (FRC), both mean end-diastolic dimension and mean end-systolic dimension increased (5·1±0·4 to 5·4±0·5 cm; P<0.001 and 3·7± 0·4 to 3·9± 0·4 cm; P<0·025, respectively). At high lung volume (HLV), midway between FRC and total lung volume, mean end-diastolic dimension increased from 5·1±0·5 to 5·3±0·5 cm (P<0·001), less than the increase at FRC, and mean end-systolic dimension increased from 3–520.4 to 3·9±0·4 cm (P<0–001), similar to the increase at FRC. Thus, mean stroke dimension and shortening fraction were reduced at HLV (1·5 ± 0·2 to 1·3 ± 0·2 cm and30 ± 4to26 ± 2% respectively, P < 0·025). At FRC and HLV respectively, mean left ventricular transmural pressure increased from 111 to 129 Torr (P<0·001) and from 111 to 128 Torr (P<0·001) in response to the Mueller manoeuvre, although intraesophageal (intrathoracic) pressure was significantly lower (P < 0·001) during the Mueller manoeuvre at HLV. These results show that lung volume affects the left ventricular response to the Mueller manoeuvre. Furthermore, the changes in left ventricular dimensions induced by the Mueller manoeuvre are determined by the level of reduced intrathoracic pressure, through differing effects on left ventricular afterload and filling.     

Atrioventricular plane displacement correlates closely to circulatory dimensions but not to ejection fraction in normal young subjects

Aims Mitral atrioventricular plane displacement (AVPD) provides information about left ventricular systolic function. M‐mode of systolic annulus amplitude or tissue Doppler imaging of systolic annulus velocity are the current methods of evaluating AVPD. A correlation to ejection fraction (EF) has been demonstrated in patients with coronary artery disease and left ventricular dysfunction. Our aim was (i) to investigate the mitral AVPD of normal subjects with different physical work capacities and (ii) to further evaluate AVPD as an index of left ventricular systolic function. Methods and results Twenty‐eight healthy men mean age 28 years (20–39) were included: endurance trained (ET) (n=10), strength trained (ST) (n=9) and untrained (UT) (n=9). The systolic AVPD was recorded at four sites, septal, lateral, anterior and posterior, using M‐mode. Left ventricular volumes were calculated according to Simpson’s rule. Systolic AVPD was higher in endurance trained, 16·9 ± 1·5 mm, as compared with both strength trained, 13 ± 1·6 (P<0·001) and untrained, 14 ± 1·6 (P<0·001). Left ventricular systolic AVPD correlated strongly with end‐diastolic volume (r=0·82), stroke volume (r=0·80) and maximal oxygen consumption per body weight (r=0·72). The correlation between AVPD and EF was poor (r=0·22). Conclusion In the subjects studied, with a range of normal cardiac dimensions, AVPD correlated to stroke volume, end‐diastolic volume and maximal oxygen consumption per body weight, but not to EF. On theoretical grounds, it also seems reasonable that a dimension like AVPD is related to other cardiac dimensions and volumes, rather than to a fraction, like EF. AVPD is one parameter that is useful for evaluation of left ventricular systolic function but is not interchangeable with other measurements such as EF.     

Relationship between hyperglycaemia and aerobic power in men with newly diagnosed type 2 (non insulin-dependent) diabetes

Summary. The aim of the study described here was to evaluate aerobic function during exercise and its determinants in middle-aged men with newly diagnosed Type 2 (non insulin-dependent) diabetes. Using breath-by-breath technique, we measured O₂ uptake at anaerobic (ventilatory) threshold and at peak exercise in a group of diabetic men (n= 19; fasting blood glucose 8.6 ± 0.7 mmol l^-1, mean ± SEM) without any disease or medication that could have had an influence on exercise performance, and compared the results to those observed in non-diabetic healthy control men (n= 18). There were no differences in physical activity or smoking habits between the groups. Oxygen uptake was lower in the diabetic men than in the control men both at anaerobic threshold (15.0 ± 0.8 vs. 18.8 ± 1.0 ml min^-1 kg^-1, P< 0.01) and at peak exercise (25.3 ± 1.5 vs. 31.1 ± 1.4 ml min^-1 kg^-1, P<0.01). In the diabetic men peak O₂ uptake showed an inverse linear correlation with age (r= -0.71, P≤0.001), fasting blood glucose (r= -0.49, P<0.05) and glucose response in an oral glucose tolerance test (r=-0.43, P<0.05). In addition, long-term smoking was associated with impaired peak O₂ uptake. In a stepwise multiple regression procedure 75% of the total variance of peak O₂ uptake in the diabetic men was explained by age, post-load blood glucose response and smoking history. Thus, in addition to ageing and smoking, hyperglycaemia is correlated with impaired aerobic power in men with newly diagnosed Type 2 diabetes.     

早期新生儿脉冲组织多普勒超声心动图的研究

目的 探讨脉冲组织多普勒技术评价早期新生儿心功能并了解心动周期中各时间间期及其随心率的变化规律.方法 86例出生2天、3天、4天新生儿,采用TDI技术检测早期新生儿二、三尖瓣环运动,测量收缩期峰值速度(Sa),舒张早期峰值速度(Ea)与舒张晚期峰值速度(Aa)比值(Ea/Aa),E与Ea比值(E/Ea),以及TDI频谱各时间间期.分别以日龄和性别分组,比较组间以及左右室之间上述各指标差异性,并进行时间间期与心率的相关性分析.结果 Sa、Ea/Aa及E/Ea在不同H龄间差异均无显著性(P＞0.05).男性新生儿与女性二尖瓣环左室侧Ea/Aa(0.89±0.31 vs 1.09±0.29,P=0.005)及E/Ea(10.98±2.24 vs 9.38±2.62,P=0.008)、三尖瓣环与二尖瓣环Sa(5.74±0.10 vs 4.30±0.93,P=0.000)、Ea/Aa(0.85±0.25 vs 1.00±0.32,P=0.003)及E/Ea(7.22±2.42 vs 10.09±2.57,P=0.000)差异均有显著性.各时间间期在不同口龄组间差异无显著性;男性新生儿与女性左室总舒张时间(207.14±34.70 vs 230.00±48.16,P=0.013)差异具有显著性;除外舒张后期时间,所有时间间期指标左右室间差异均有显著性(P＜0.01).新生儿收缩时间与舒张时间之比约0.54/0.46.心率与舒张早期时间、舒张后期时间强负相关(r=-0.547,-0.687).与心房收缩时间无相关关系,而与等容收缩时间,射血时间均弱负柑关(r=-0.280,-0.374).结论 早期新生儿心功能日龄间无差异;女性新生儿的心室舒张功能优于男性,而收缩功能无性别差异.左室舒张时间男性新生儿短于女性;右室的收缩早于左室,并且右室的收缩时间比左室长.心率增快主要影响舒张后期时间和舒张早期时间,与心房收缩时间无相关关系.