Early diastolic motion of the posterior aortic root as an index of left ventricular filling

Aortic root motion on M-mode echocardiography is related to left atrial volume change. Early diastolic motion of the aortic root has been quantified by the atrial emptying index. This index has been shown by some investigators to assess early diastolic left ventricular filling, while other investigators report conflicting findings. To evaluate further early diastolic motion of the posterior aortic root, we describe a new echocardiographic parameter—the slope of early diastolic posterior aortic root motion. This parameter appears superior to the atrial emptying index in assessing early diastolic left ventricular filling. Forty-one patients were studied by M-mode echocardiography and were divided into group I (17 patients) with diminished E to F mitral value slopes (<70 mm/sec) and group II (24 patients) with normal E to F mitral valve slopes (≥70 mm/sec). Patients in group I and group II had comparable left atrial sizes and left ventricular dimensions. The aortic root slope and normalized aortic root slope (normalized for left atrial dimension) in group I (3.7 ± 1.4 cm/sec and 1.0 ± 0.4 sec^?1, respectively) were significantly less than in group II (6.4 ± 1.4 cm/sec and 1.9 ± 0.6 sec^?1, respectively). The atrial emptying index and atrial emptying index normalized for heart rate were not different between the two groups. When the 41 patients were analyzed according to the presence or absence of left ventricular hypertrophy by echocardiography, only the normalized aortic root slope was significantly different in patients with or without left ventricular hypertrophy. A significant linear correlation (r = 0.84, P < 0.0005) was found between the aortic root slope or normalized aortic root slope and the E to F slope of the mitral valve. Significant correlations also existed between the aortic root slope and the slope of early diastolic left ventricular rapid filling. Therefore, the slope of early diastolic motion of the posterior aortic root appears to be a useful and easily obtainable echocardiographic parameter to assess early diastolic left ventricular filling.     

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.     

The relationship between tissue Doppler imaging and seric NTproBNP levels in sinus rhythm patients: a prospective study

N-terminal pro-brain natriuretic peptide (NTproBNP) correlates with left ventricular (LV) filling pressure. The ratio between early diastolic transmitral velocity and early mitral annular diastolic velocity (E/Ea) reflects LV filling pressure in a variety of cardiac diseases. However this relationship was not validated in some categories of patients. Our aim was to evaluate the correlation between tissue Doppler velocities of the mitral annulus and NTproBNP levels in sinus rhythm patients. Methods Echocardiography was performed in 111 consecutive patients simultaneously with NTproBNP measurement. E/Ea and E/(Ea × Sa) were calculated (Sa is the maximal systolic velocity of mitral annulus); the average of the velocities of septal and lateral mitral annulus was used. Results Simple regression analysis demonstrated a significant linear correlation between E/(Ea × Sa) and NTproBNP (r = 0.71, P < 0.0001), superior to E/Ea correlation (r = 0.58, P < 0.0001). Significant but weaker correlations were found between NTproBNP and Sa, pulmonary artery systolic pressure, Ea, mitral E/A (early/late diastolic transmitral velocity), E wave, mitral E deceleration time and LV ejection fraction (LVEF). The optimal E/(Ea × Sa) cut-off for prediction of NTproBNP levels > 900 pg/ml was 1.5 (sensitivity = 81%, specificity = 70%). Among analyzed parameters, E/(Ea × Sa) was best correlated with NTproBNP levels in patients with LVEF ≥ 50% (r = 0.80, P < 0.0001), with depressed LVEF (<50%) (r = 0.66, P < 0.0001), with regional wall motion abnormalities (r = 0.75, P < 0.0001), and with E/Ea 8 to 15 (r = 0.58, P < 0.0001). Conclusions E/(Ea × Sa) strongly correlates with NTproBNP, regardless of LVEF, and can be a simple and accurate echocardiographic index in patients in sinus rhythm, particularly in those with regional wall motion abnormalities or intermediate E/Ea.     

Value of assessment of tricuspid annulus: real-time three-dimensional echocardiography and magnetic resonance imaging

Aim To detect the accuracy of real-time three-dimensional echocardiography (RT3DE) and two-dimensional echocardiography (2DE) for tricuspid annulus (TA) assessment compared with magnetic resonance imaging (MRI). Methods Thirty patients (mean age 34 ± 13 years, 60% males) in sinus rhythm were examined by MRI, RT3DE, and 2DE for TA assessment. End-diastolic and end-systolic TA diameter (TAD) and TA fractional shortening (TAFS) were measured by RT3DE, 2DE, and MRI. End-diastolic and end-systolic TA area (TAA) and TA fractional area changes (TAFAC) were measured by RT3DE and MRI. End-diastolic and end-systolic right ventricular (RV) volumes and ejection fraction (RV-EF) were measured by MRI. Results The TA was clearly delineated in all patients and visualized as an oval-shaped by RT3DE and MRI. There was a good correlation between TAD_MRI and TAD_3D (r = 0.75, P = 0.001), while TAD_2D was fairly correlated with TAD_3D and TAD_MRI (r = 0.5, P = 0.01 for both). There were no significant differences between RT3DE and MRI in TAD, TAA, TAFS, and TAFAC measurements, while TAD_2D and TAFS_2D were significantly underestimated (P < 0.001). TAFS_2D was not correlated with RV-EF, while TAFS_3D and TAFAC_3D were fairly correlated with RV-EF (r = 0.49, P = 0.01, and r = 0.47, P = 0.02 respectively). Conclusion RT3DE helps in accurate assessment of TA comparable to MRI and may have an important implication in the TV surgical decision-making processes. RT3DE analysis of TA function could be used as a marker of RV function.     

实时三维超声心动图评估射血分数减低的左心力衰竭患者的右心室重构

目的 采用单心动周期实时三维超声心动图(sRT-3DE)结合传统二维超声心动图探讨左心室射血分数(LVEF)减低的左心力衰竭患者肺高压(PH)对右心室重构的影响。方法 对sRT-3DE检查LVEF<50%的60例患者(病例组)根据肺动脉收缩压(PASP)及肺血管阻力(PVR)不同分为3个亚组:HF-NPH亚组15例,HF-PPH亚组15例,HF-RPH亚组30例,正常健康人35名为对照组。对两组行常规二维超声及sRT-3DE检查,分析获得三维、二维及多普勒超声参数,进行组间对比分析和相关性分析。结果 与对照组比较:病例组右心室舒张末期容积指数(EDVI)、收缩末期容积指数(ESVI)、基底部横径(D1)、长径(LD)、D1/中间横部径(D2)、射血分数(EF)减小。与HF-NPH亚组比较,HF-PPH亚组右心室ESVI、D1/D2、LD/D2增大。与HF-PPH亚组比较,HF-RPH亚组右心室EDVI、ESVI、D2增大,右心室EF、LD/D2减低。PVR与PASP、右心室EF与左心室EF、右心室LD与左心室LD呈正相关性(r=0.765、0.628、0.725;P均<0.01),PVR与右心室EF呈负相关(r=-0.715,P<0.01),且高于与PASP的相关性(r=-0.623,P<0.01)。结论 sRT-3DE结合传统二维及多普勒超声可准确评估左心力衰竭患者的右心室重构,有助于判断右心室结构和功能状态。     

实时三维超声心动图定量评价原发性高血压患者右心室舒张功能

目的 探讨实时三维超声心动图(RT-3DE)定量评价原发性高血压(PH)患者右心室舒张功能的价值。方法 收集51例PH患者和51名健康志愿者(对照组),根据左心室质量指数将PH患者分为非左心室肥厚(NLVH)组和左心室肥厚(LVH)组。采用多普勒超声测量三尖瓣口舒张早期峰值血流速度(E)、舒张晚期峰值血流速度(A)、三尖瓣前瓣环处舒张早期心肌运动速度(Ea)、舒张晚期心肌运动速度(Aa),计算E/A、Ea/Aa和E/Ea;应用RT-3DE时间-容积曲线,计算右心室舒张期充盈1/4、1/3、1/2、3/4容积的时间比率(D_1/4、D_1/3、D_1/2、D_3/4),计算1/3充盈分数(1/3 FF)、峰值充盈率(PFR)。比较组间上述参数差异,分析PH患者上述参数间的相关性。结果 NLVH组16例、LVH组35例,其E/A、Ea/Aa均小于对照组(P均<0.05);NLVH组Ea、E/Ea与对照组比较差异均无统计学意义(P均>0.05),而LVH组Ea小于对照组、E/Ea大于对照组(P均<0.05);NLVH和LVH组D_1/4、D_1/3、D_1/2和D_3/4均高于对照组(P均<0.05),PFR和1/3 FF均低于对照组(P均<0.05);NLVH和LVH组上述参数差异均无统计学意义(P均>0.05)。PH患者D_1/4、D_1/3、D_1/2和D_3/4与E/Ea呈正相关,PFR、1/3 FF与E/Ea呈负相关(P均<0.05)。结论 应用RT-3DE能直接获得右心室容积随时间变化的相关参数,对评价PH患者右心室舒张功能有重要指导意义。     

Velocity vector imaging to quantify left atrial function

The aim of our study was to assess the feasibility of a new image analysis, velocity vector imaging (VVI), in the assessment of left atrial volumes (LAV) and left atrial ejection fraction (LAEF). We retrospectively analysed 100 transthoracic echocardiographic findings in 71 men, and 29 women (mean age 57 ± 19.8 years). Two subgroups of patients were defined: (1) with left ventricular (LV) EF > 50%, and (2) LV EF < 50%. For the VVI method of indexed LAV assessment we used the apical four-chamber view. From the displacement of LA endocardial pixels time–volume curves were extracted which provided automatically data regarding indexed maximum LAV (LAVImax), indexed minimum LAV (LAVImin), and LAEF. LAVs and LAEF by 2-dimensional echocardiograhy (2DE) were measured by Simpson’s biplane disc summation method. Comparing LAVImax, LAVImin, and LAEF by VVI versus 2DE in the total study population, we found significant correlations: r = 0.94, P < 0.0001, r = 0.94, P < 0.0001, r = 0.79, P < 0.0001, respectively. In addition, LAVImax ≥ 40 ml/m² was 94% sensitive and 72% specific, LAVImin ≥ 27 ml/m² was 90% sensitive and 86% specific, and LAEF < 30% was 80% sensitive and 96% specific for the detection of LV systolic dysfunction. There were highly significant inverse associations of LAVImax and LAVImin to LVEF. LAEF was also significantly related to LV systolic function. When comparing the time required for VVI and 2DE measurements, VVI led to 62% reduction in the measurement time. In conclusion, VVI is a feasible method for the assessment of LAVs and LAEF. It provides close agreement with that measured by conventional 2DE Simpson’s biplane method with significant time saved.     

Changes in left ventricular function in shocked newborns

Objective: To assess whether the change in cardiac output after volume replacement is due to elevation of stroke volume or heart rate and to determine the effect of mechanical ventilation on the hemodynamic situation. Design: Prospective study. Setting: A ten-bed neonatal intensive care unit (level III) at a university hospital. Patients: 15 consecutive newborns with blood pressure below the 10^th percentile related to age and weight. Interventions: Volume replacement with Ringer's lactate 20 ml/kg body weight. Measurements and results. Before and after volume replacement, arterial pressure recordings, blood gas analysis, and an echocardiographic study were carried out. Left ventricular and aortic diameters were measured by the two-dimensional M-mode technique and velocity time integral of aortic flow by the pulsed color Doppler technique. From these data, stroke volume and cardiac output were calculated. Cardiac output (703 ± 204 vs 826 ± 166 ml/min, p < 0.005) and cardiac index (267 ± 69 vs 302 ± 55 ml/min per kg body weight, p < 0.01) changed significantly due to an appreciable elevation in stroke volume (5.2 ± 1.7 vs 5.8 ± 1.7 ml, p < 0.05), whereas heart rate was unaltered (140 ± 12 vs 142 ± 20 beats/min; NS). The change in blood pressure (32 ± 5 vs 38 ± 8 mm Hg, p < 0.01) was also significant. Cardiac index before and after volume replacement showed a significant inverse correlation with the severity of respiratory disease expressed as alveolar-arterial oxygen difference (A-aDO₂) (A-aDO₂ vs cardiac index before volume replacement: r = − 0.77, p < 0.001; after volume replacement: r = − 0.73, p < 0.005) or oxygenation index (oxygenation index vs cardiac index before volume replacement: r = − 0.73, p < 0.005; after volume replacement: r = − 0.73, p < 0.005). Changes in left ventricular diastolic diameter, left ventricular systolic diameter, and fractional shortening were not significant. Conclusions: These results indicate that the major regulator of left ventricular output in newborns with hypovolemic or cardiogenic shock is stroke volume and not heart rate and that cardiac output depends on the severity of the respiratory disease. Received: 21 March 1997 Accepted: 8 July 1997     

Comparison of strain doppler echocardiography and radiologic left ventriculography for quantitative assessment of regional myocardial function

Objective We aimed to study the comparison of strain and strain rate parameters with conventional left ventriculography derived regional function. Method Forty patients were included in the study. The study group was selected from patients who had undergone left ventriculography and coronary angiography for clinical indications. Regional myocardial function was assessed using the centerline method via ACOM PC Quantcor LVA measurement system. Patients were also evaluated with echocardiography. Strain and strain rate Doppler echocardiographic measurements were compared with conventional left ventriculography at anterobasal, anterolateral, inferior and posterobasal segments. Results Radiological left ventricular radial shortening was found to correlate with longitudinal strain shortening in all ventriculographic segments examined (anterobasal, r = 0.771, P < 0.0001; anterolateral, r = 0.790, P < 0.0001; posterobasal, r = 0.861, P < 0.0001; inferior, r = 0.815, P < 0.0001). Correlation was persistent both in patients with or without coronary artery disease. The sensitivity of a peak systolic longitudinal strain >12.5% for prediction of patients with radial shortening ≥20% was 75%, with a specificity of 100%. However, no relationship could be demonstrated between radiological left ventricular radial shortening and strain rate measurements. Conclusions In our study it was shown that regional wall motion can be measured quantitatively via strain Doppler echocardiography with the left ventriculography as reference.     

Age-dependency of left ventricular filling dynamics and relaxation as assessed by pulsed Doppler echocardiography

Summary. Left ventricular diastolic function was assessed from transmitral flow velocity curves as measured by Doppler echocardiography in healthy individuals aged 21–69 years, each decade comprising 12 subjects. By ageing, progressive changes in the various filling parameters were observed. When comparing the youngest and oldest age groups, the ratio between peak velocities in early and late diastole decreased from 2.0±0.3 to 1.2±0.3 (P<0.001). The filling fraction of first third of diastole decreased from 54 ± 5% to 45 ± 4% (P<0.001). Isovolumic relaxation time increased from 61 ± 11 ms to 77 ± 12 ms (P<0.01). Correlation coefficients of velocity ratio, filling fraction and isovolumic relaxation time vs. age were r= -0.71 (P<0.001), r= -0.56 (P<0.001) and r= 0.44 (P<0.001), respectively. When isovolumic relaxation time and age were used together in multivariate regression analysis, only age was an independent predictor of velocity ratio and filling fraction. Stroke volume, peak velocity in left ventricular outflow tract, heart rate and systolic blood pressure were similar in all age groups. Thus, velocity ratio and filling fraction indicated a relative filling shift towards late diastole by ageing and were more sensitive than s?ystolic parameters in reflecting age-related changes in cardiac function. The changes could be explained neither by delayed relaxation nor by change in systolic parameters. When using Doppler echocardiography for evaluation of left ventricular filling, agematching of reference groups is necessary.     

Cardiac structure and function in a mouse model of uraemia without hypertension

Kidney dysfunction is often associated with cardiac left ventricular hypertrophy and increased cardiovascular mortality. Objective. The aim of this study was to find out whether this reflects direct effects of uraemia on the heart or is dependent on accompanying hypertension. Material and methods. Apolipoprotein‐E (apoE)‐deficient C57BL/6 mice are resistant to development of hypertension after renal mass reduction. To evaluate the impact of uraemia without hypertension on the heart, apoE‐deficient mice underwent 5/6 nephrectomy (NX) or sham operation (Sh) and were randomized to treatment with the angiotensin converting enzyme inhibitor enalapril (12?mg?kg^?1?d^?1) or no medication. Results. NX did not affect systolic blood pressure (BP), but reduced mean creatinine clearance, body weight and blood haemoglobin to 27?% (p<0.01), 82?% (p<0.0001) and 73?% (p<0.0001), respectively, of the values in Sh mice. Thirty‐six weeks after NX, heart wet weight, echocardiographic estimates of left ventricular mass and left ventricular diastolic and systolic functions were similar in NX and Sh mice. NX did not increase cardiac fibrosis or cardiac mRNA expression of biglycan, whereas it decreased the mRNA expression of procollagen (p<0.01). Enalapril reduced BP (p<0.001), heart wet weight and estimated left ventricular mass in both NX (p<0.01) and Sh mice (p<0.05), but did not affect cardiac diastolic or systolic function. Conclusions. The results suggest that uraemia does not impair cardiac structure or function in apoE‐deficient mice. Since NX has no effect on BP in apoE‐deficient mice, the results may indicate that hypertension is important for development of left ventricular disease in uraemia.     

Echocardiographic Tissue Characterization Demonstrates Differences in the Left and Right Sides of the Ventricular Septum

The left and right ventricular function of the heart are influenced by the complex structure of the ventricular septum. The cyclic variation of ultrasonic backscatter over the cardiac cycle is known to be sensitive to both structural and functional characteristics of the myocardium. The objective of this study was to investigate differences in the measured magnitude and normalized delay of cyclic variation between the left and right sides of the ventricular septum in normal adult subjects (N = 31). The measured mean magnitudes of cyclic variation were found to be 4.9 ± 0.4 dB and 2.4 ± 0.3 dB (mean ± SE; p < 0.0001) and the corresponding normalized delay values were found to be 0.94 ± 0.05 and 1.59 ± 0.12 (mean ± SE; p < 0.0001) for the left and right sides, respectively. These results show significant differences in the measured magnitude and normalized delay of cyclic variation between the left and right sides of the ventricular septum in normal subjects that appear consistent with predictions based on previously described models of cyclic variation of backscatter and reported measurements of transmural differences in strain properties of the septum. (E-mail: mrh@wuphys.wustl.edu)     

Myocardial viability by contrast-enhanced cardiovascular magnetic resonance in patients with coronary artery disease: comparison with gated single-photon emission tomography and FDG position emission tomography

Background The aim of this study was to assess the value of contrast-enhanced cardiovascular magnetic resonance (CMR) in viability for patients with coronary artery disease and left ventricular (LV) dysfunction (ejection fraction [EF] ≤50%), comparing to gated thallium-201 (²⁰¹Tl) single photon emission computed tomography (SPECT) and ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET). Methods and Results One hundred sixteen patients (EF 37.8 ± 16.2%) underwent stress-reinjection or rest-redistribution gated-SPECT and CMR (46 FDG-PET) within 1 month. All images were analyzed in a 17-segment and 0–4 scales system. Of 1972 segments, delayed enhancement (DE) on CMR correlated well with ²⁰¹Tl reduction (r = 0.90, p < 0.0001). The agreement of SPECT (≥50% maximal ²⁰¹Tl activity) and CMR (≤50% DE) was 96.8% (κ = 0.62). CMR detected more subendocardial scars in 18 subjects (60 segments). Reduced ²⁰¹Tl activity but none DE were observed in 19 subjects (76 segments; more inferior) who had lower EF and larger end-systolic volume (p < 0.05). Of 411 dysfunctional segments from 46 patients, FDG-PET (≥50% of maximal FDG uptake) detected more viability (9%). Conclusion The extent of DE correlated ²⁰¹Tl activity well. CMR could detect more small infarcts, while FDG-PET could detect more viability. CMR could distinguish between artifacts or infarction on SPECT, especially in poor LV function.     

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.     

实时三维超声心动图估测左心室容量的实验研究

目的初探实时三维超声心动图(3DE)估测心室容量的可行性和准确性.方法应用Philips公司实时3DE系统采集19只离体猪心金字塔形数据库,结合相应测量软件用心尖长轴系列平面法分别测量左室容量,并与二维双平面Simpson法和猪心左室排水法实测值比较.结果从方差分析、SNK检验及直线相关分析看:实时3DE 16平面法(23.31±14.29)ml、8平面法(23.42±14.56)ml估测左室容量值与猪心左室排水法实测值(23.79±14.78)ml差异无统计学意义(P＞0.05),实时3DE 2平面法(17.94±10.46)ml和二维超声双平面Simpson法(19.67±13.46)m1测值与排水法实测值差异则有统计学意义(P＜0.05).而且实时3DE 16平面和8平面法测值与排水法实测值高度相关(r=0.98,P＜0.0001),二维超声双平面Simpson法则较逊(r=0.89).结论实时3DE是心室容量准确估测的又一可靠手段.     

Transthoracic electrical impedance as an index of extracellular fluid volume in man

Findings in 76 subjects without cardiac failure were analyzed to detect relationships between observed changes in transthoracic electrical impedance (TEI) and total body extracellular fluid volume (ECFV) during various manoeuvres and between absolute TEI and ECFV values. TEI was normalized to electrode distance (Z₀/gDel) and ECFV to lean body mass (ECFV/LBM). A distircet relation was found between percent changes of TEI and ECFV (r=-0.76, p<0.0001) and between absolute Z₀/el and ECFV/LBM values (r=-0.66, p<0.0001 for men; r=-0.61, p<0.0001 for women). It is concluded that in the same subject a change in TEI is possibly a sensitive index for a change in ECFV and that a single measurement of TEI, normalized to electrode distance, gives information about the state of hydration (ECFV) of patients without cardiac failure.     

Predictive value of the echocardiographic left atrial dimension in isolated ventricular septal defect

Echocardiographic left atrial dimension has been reported to correlate with left-to-right shunt (Qp/Qs) in children with isolated ventricular septal defect (VSD) or patent ductus arteriosus (PDA). In 17 children with isolated VSD, we prospectively compared Qp/Qs with the ratio of echocardiographic left atrial dimension to aortic root diameter (LAD/Ao) and with the left atrial dimension corrected for body surface area (LAD/M²). The correlation between LAD/Ao and Qp/Qs was not statistically significant (r = 0.49, p > 0.05). The LAD/M² correlated significantly with Qp/Qs (r = 0.66, p < 0.01); however, prediction intervals were excessively wide. Our findings indicate that it is inappropriate to predict Qp/Qs in these patients from echocardiographic LAD.     

四维自动左心室定量分析技术评价左心室功能与几何形态改变的关系

目的 应用四维自动左心室定量分析工具（4D Auto LVQ）与二维超声心动图（2DE）对比分析左心室扩大者心室几何形态及收缩功能,探讨左心室几何形态改变与收缩功能的关系。方法 以左心室球形指数作为反映左心室几何构型变化的指标,应用2DE及RT-3DE测量39名健康志愿者（正常组）和60例左心室扩大患者（左心室扩大组）的左心室舒张末期容积（LVEDV）、左心室收缩末期容积（LVESV）、左心室射血分数（LVEF）及二维舒张末期球形指数^-1（SId^-1）和三维球形指数（SPI）,并进行相关性分析。结果 与正常组比较,左心室扩大组LVEDV、LVESV及SPI增加,LVEF减小;2DE与RT-3DE所获得的LVEDV、LVESV、LVEF及球形指数值显著相关（P均<0.05）。左心室扩大组中,RT-3DE和2DE分别所测球形指数与LVEF呈负相关,球形指数与LVEDV、LVESV呈正相关（P<0.05）,SPI与LVEF的相关性高于SId^-1与LVEF（r=-0.553 vs r=-0.457,P<0.05）。结论 应用4D Auto LVQ技术可较简捷、直观显示并测量左心室几何形态及收缩功能;球形指数与LVEF、LVEDV、LVESV显著相关。     

Model for radionuclide evaluation of left-to-right ductal shunts

Summary. A model for radionuclide evaluation of left-to-right ductal shunts was designed. It was a generalization of the standard Maltz-Treves method, accounting for the possibility that distribution of the shunt flow between the two lungs differs from that in the right ventricular (RV) output (F_s). This yields a new formulation in which the ratio of ductal flow to pulmonary flow (F_d/F_p) equals a weighted average of F_d/F_p obtained separately for the right lung (RL) and the left lung (LL), i.e. F_d/F_p= R(F_d/F_pP)_RL+ (1-R) (F_d/F_p)_LL; where R is the fraction of the RV output going to the right lung. Separate shunt-flow ratios can be obtained by conventional analysis of the respective lung radiohistogram, while R can be determined from the upslopes of these curves. Formulas were derived rigorously from basic principles, so that the ultimate clinical validity of the method depends on radioangiographic assessment of R, (F^d/F^p)^RL and (F_d/F_p)_LL. Due to asymmetry of flows there is no true referent method for patients with ductal shunts. Therefore a simulation study, using quasi-real data, was utilized, yielding satisfactory performances of the algorithm: (F_p/F_s)_calculated= 0–92 (F_p/F_s)_simulated+ 015 (r= 0–878).,     

Echocardiographically estimated left ventricular end-diastolic and right ventricular systolic pressure in normotensive healthy individuals

Aim To study the effect of aging on and the relationship between echocardiographically estimated left ventricular (LV) filling pressure and estimated right ventricular (RV) systolic pressure among healthy normotensive individuals.Methods We analyzed 249 healthy individuals (aged 18–82 years, 52% men) with normal echocardiographic findings and reliably measurable tricuspid regurgitation gradients. Subjects with blood pressure >140/90 mmHg and/or LV hypertrophy were excluded. LV & RV dimensions and LV mass were measured with M-mode echocardiography. Atrial (A) volumes were determined with the area-length method. Diastolic function was assessed with transmitral Doppler and mitral annulus tissue Doppler. The ratio of transmitral early peak velocity to early diastolic mitral annulus velocity (E/E′) was used as estimation of LV filling pressure. The transtricuspid Doppler gradient was used to estimate RV end-systolic pressure.Results Even in normotensive individuals aging was accompanied by an increase in LV mass and LA dimensions and an increase in relaxation abnormalities. E/E′ increased with every decade: from 7.8 for age 18–35 years to 10.9 for age ≥75 years (p<0.0001) as did the transtricuspid gradient: from 18.3 mmHg for age 18–35 years to 25.8 mmHg for age ≥75 years (p<0.0001). Linear regression showed that estimated RV systolic pressure was independently predicted by age, LA volume, LV systolic function and E/E′.Conclusion Among normotensive healthy individuals both E/E′ and tricuspid regurgitation gradients increase significantly with aging. Moreover the E/E′ ratio was independently predicting the tricuspid regurgitation gradient. These findings support the need for further studies defining age specific normal values.