Determination of left ventricular wall thickness and muscle mass by intravenous digital subtractionangiocardiography: validation of the method

Left ventricular (LV) wall thickness and muscle mass are importantmeasures of LV hypertrophy. In 24 patients LV end-diastolicwall thickness and muscle mass were determined (two observers)by digital subtraction angiocardiography (DSA) and conventionalLV angiocardiography (LVA). Wall thickness was determined overthe anterolateral wall of the left ventricle according to thetechnique of Rackley (method 1) or by planimetry (method 2).Seventeen patients were studied at rest and seven during dynamicexercise. Wall thickness correlated well between LVA and DSA;the best correlations were obtained by a combined subtractionmode using either method 1 or 2 (method 1, r0–80; method2,r0. 75). The standard error of estimate of the mean (SEE) wasslightly lower for method 2 ( 10%) than for method 1 ( 13%).DSA significantly overestimated wall thickness by 5–7%with method 1 and underestimated by 12–14% with method2. Muscle mass correlated well between LVA and DSA; the SEEwas 15% for method 1 and 12% for method 2. Overestimation ofmuscle mass by DSA was 7–11% with method 1 and underestimationwas 13–15% with method 2.It is concluded that LV wallthickness can be determined accurately by DSA with an SEE rangingbetween 10 and 13%. Determination of LV muscle mass is slightlyless accurate and the SEE is slightly larger ranging between13 to 17%. With method 1, wall thickness and muscle mass wereover estimated and with method 2 underestimated.     

Left ventricular wall thickness measurements by magnetic resonance: a validation study

Summary Left ventricular (LV) wall thickness was determined by magnetic resonance (MR) in 15 patients (7 controls and 8 patients with coronary artery disease). End-diastolic (ed) and end-systolic (es) wall thickness were measured in a short axis view perpendicular to the LV long axis. Wall thickness measurements were compared to data obtained by digital subtraction angiography (DSA) and M-mode echocardiography (Echo).End-diastolic and end-systolic wall thickness were significantly overestimated by MR (34% and 37%, respectively) when compared to DSA. In contrast, LV end-diastolic and end-systolic chamber diameter were significantly underestimated by MR (25% and 30%, respectively) when compared to DSA. However, fractioned shortening was similar (all NS) for MR (48±22%), DSA (54±15%) and Echo (44±10%), respectively.The mean difference (= accuracy) and the standard deviation of difference (= precision) for LV wall thickness was 0.4±0.2 cm between MR and DSA, 0.4±0.3 cm between MR and ECHO and 0.03±0.1 cm between DSA and ECHO. The correlation of wall thickness between MR and DSA (correlation coefficient r=0.74, p<0.001) and between MR and Echo (r=0.70, p<0.001) was good although the standard error of estimate (SEE) was 17% for MR vs. DSA and 21% for MR vs. Echo. The corresponding SEE for chamber diameter was 16% between MR and DSA and 19% between MR and Echo, respectively. Intraobserver variability for wall thickness determination by MR was excellent (correlation coefficient r=0.99, p<0.001) SEE of 4%. Interobserver variability was also good (correlation coefficient r=0.90, p<0.001) with a SEE of 12%.It is concluded that LV wall thickness and chamber diameter (short axis plane) can be determined by MR with good precision but only satisfactory accuracy. LV wall thickness is significantly overestimated probably due to signals from static blood which might be indistinguishable from the subendocardium.     

Left ventricular function during transient coronary occlusion: digital subtraction left ventriculograms during coronary angioplasty

The impact of transient myocardial ischemia on left ventricular function was examined by digital subtraction left ventricular angiography. Contrast medium was injected into the right pulmonary artery before, at 60 seconds of balloon inflation, and 10 minutes after balloon deflation. A total of 69 patients completed the study. In 52 patients, the left anterior descending artery (LAD) was involved, and in 17, the right coronary artery (RCA) was the focus. Ejection fraction (EF) declined by balloon inflation and returned to baseline value after deflation of the balloon. There was tendency toward a lower EF and wider akinetic area for LAD dilatation. The linear correlation between resting EF and EF during balloon inflation suggested that the effect of momentary coronary occlusion on left ventricular function appears to be additive to pre-existing left ventricular dysfunction, and resting ejection fraction is an important parameter for estimating the degree of diminished left ventricular function during myocardial ischemia.     

Impact of body mass index on markers of left ventricular thickness and mass calculation: results of a pilot analysis

Specific correlations between body mass index (BMI) and left ventricular (LV) thickness have been conflicting. Accordingly, we investigated if a particular correlation exists between BMI and echocardiographic markers of ventricular function. METHODS: A total of 122 patients, referred for routine transthoracic echocardiography, were included in this prospective pilot study using a 3:1 randomization approach. Patient demographics were obtained using a questionnaire. RESULTS: Group I consisted of 80 obese (BMI was >30 kg/m2), Group II of 16 overweight (BMI between 26 and 29 kg/m2), and Group III of 26 normal BMI (BMI < 25 kg/m2) individuals. No difference was found in left ventricular wall thickness, LV end-systolic cavity dimension, fractional shortening (FS), or pulmonary artery systolic pressure (PASP) among the groups. However, mean LV end-diastolic cavity dimension was greater in Group I (5.0 +/- 0.9 cm) than Group II (4.6 +/- 0.8 cm) or Group III (4.4 +/- 0.9 cm; P < 0.006). LV mass indexed to height(2.7) was also significantly larger in Group I (61 +/- 21) when compared to Group III (48 +/- 19; P < 0.001). Finally, left atrial diameter (4.3 +/- 0.7 cm) was also larger (3.8 +/- 0.6 and 3.6 +/- 0.7, respectively; P < 0.00001). DISCUSSION: We found no correlation between BMI and LV wall thickness, FS, or PASP despite the high prevalence of diabetes and hypertension in obese individuals. However, obese individuals had an increased LV end-diastolic cavity dimension, LV mass/height(2.7), and left atrial diameter. These findings could represent early markers in the sequence of cardiac events occurring with obesity. A larger prospective study is needed to further define the sequence of cardiac abnormalities occurring with increasing BMI.     

Determination of left ventricular mass by real-time three-dimensional echocardiography: in vitro validation

Twenty-one explanted fixed hearts (14 dogs and 7 pigs) were examined to validate newly developed real-time three-dimensional (RT3D) echocardiography for measurement of left ventricular (LV) mass in vitro and to compare its accuracy and variability with those of conventional echocardiographic measurements. There was an excellent correlation and high degree of agreement for the determination of LV mass between RT3D echocardiography and true mass measurement (r = 0.98; standard error of the estimate [SEE] = 7.3 g; absolute difference [AD] = 2.8 g; y = 1.00 x -4.0, interobserver variability; 5.0%). The conventional echocardiographic methods yielded weaker correlations, larger standard errors, and interobserver variability (area-length method: r = 0.90; SEE = 13.3 g; AD = 13.2 g; 13.3 % / truncated ellipsoid method: r = 0.91; SEE = 14.7 g; AD = 10.5 g; 7. 9% / M-mode: r = 0.91; SEE = 16.2 g; AD = 9.4 g; 15.3%). Determination of LV mass by RT3D echocardiography has a high degree of accuracy and is superior to conventional one- and two-dimensional echocardiographic methods.     

Left ventricular dual-energy digital subtraction angiography: a motion immune digital subtraction technique

Digital subtraction angiography (DSA) allows quantitative analysis of ventricular function via densitometric and parametric imaging techniques. However, DSA is limited by the artifacts in temporal subtraction images that result from patient and cardiac motion. Dual-energy subtraction imaging is insensitive to motion. This study evaluated the initial application of dual-energy subtraction in cardiac patients. The image quality of dual-energy subtraction left ventriculograms obtained from a pulmonary artery injection of contrast was assessed in 13 patients, ranging in weight from 54 to 100 kg. The dual-energy images were compared with left ventricular images obtained using standard left ventricular injection cine angiography. End-systolic and end-diastolic ventricular volumes calculated from the cine (C) and dual-energy (DE) images using the Area-Length method were compared. The resulting regression line was DE=0.98 C + 7.0 ml, and the r value was 0.987. Dual-energy subtraction provided good left ventricular visualization, free from misregistration artifacts, even during patient motion.     

Repeat determination of left ventricular wall thickness from mass and volume during one cardiac cycle for the calculation of left ventricular wall stress parameters

Left ventricular end-diastolic wall stress, end-systolic wall stress, and systolic stress-time integral are important parameters to characterize left ventricular load and function. To obtain these parameters, left ventricular pressure, volume, and wall thickness data must be determined at short time intervals throughout one cardiac cycle. However, the measurement of wall thickness at short intervals (i.e., 20 ms) throughout a cardiac cycle is tedious. Furthermore, measurements of wall thickness are less accurate at end-systole compared with end-diastole. For these reasons we developed a computer program for calculating wall thickness at short intervals (20 ms) throughout the cardiac cycle from one single determination of left ventricular wall mass and repetitive measurements of left ventricular (LV) volume.     

数字减影血管造影对原发性肝癌的术前评价

目的评价数字减影血管造影（DSA）对我国原发性肝癌术前的意义。方法回顾分析1998年5月～2007年5月1000例原发性肝癌术前的DSA影像与多层螺旋CT（MSCT）及彩超检查结果。结果三种方法发现肝癌1000例,直径3em以上的700例肝癌中,DSA发现670例;240例小肝癌中DSA发现202例;30例弥漫性肝癌中,DSA发现28例;900个子灶中,DSA发现890个;440例门脉癌栓中,DSA发现362例;490例动静脉瘘、动门脉瘘中,DSA发现482例。结论DSA检查对原发性肝癌的术前评价具有不可替代的作用。     

Estimation of left ventricular systolic function by nonvolumetric echocardiographic analysis in subjects with poor left ventricular visualization: A pilot study

Background: Accurate assessment of left ventricular (LV) systolic function is an essential requirement in clinical cardiology. Several echocardiographic methods provide quantitative analysis of LV volumes and ejection fraction (EF) based on the precise tracing of endocardial borders. Often, however, technically limited studies prohibit such direct analysis, and alternative techniques must be applied. Hypothesis: Nonvolumetric echocardiographic methods which do not require endocardial edge definition and tracing may accurately provide quantitative LV systolic function data. Methods: A pilot study was conducted to validate and compare two recently described indirect echocardiographic methods of LV systolic function analysis, with LVEF by radionu-clear cardiac angiography (RNCA). Thirty-two consecutive patients undergoing RNCA for clinical indications also underwent echocardiography within 24 h, with LV analysis performed by the techniques of (1) atrioventricular plane displacement (AVPD) and (2) mitral valve leaflet coaptation point to interventricular septum distance at end-systole (MVC-IVS). Results: Thirteen patients had an echocardiogram with poor two-dimensional visualization of LV endocardial borders. One patient could not be evaluated by the MVC-IVS method and two others by the AVPD method because of technical limitations. Chi-square analysis to compare how each method could discriminate between an RNCA LVEF of < or ≥ 50% demonstrated high correlations for the AVPD method (r = 0.6530, p < 0.0005) and the MVC-IVS method (r = –0.7029, p < 0.0001). Sensitivity, specificity, positive and negative predictive values, and test accuracy for the AVPD and MVC-IVS methods were 85 and 80%, 88 and 94%, 85 and 92%, 82 and 83%, and 83 and 87%, respectively. Conclusion: This pilot study demonstrates that both alternative echocardiographic methods may be useful in the assessment of LV systolic performance, even in the setting of poor LV endocardial border visualization. A larger study is warranted to apply and contrast these methods in different patient subsets.     

Improved densitometric measurement of left ventricular ejection fraction using dual-energy digital subtraction angiography

The effects of misregistration artifacts and background corrections on the densitometric measurement of left ventricular ejection fraction (EF) from digital subtraction angiography (DSA) images were studied in 20 patients. Densitometric ejection fraction measurements were performed on both conventional time subtraction images and on dual-energy subtraction images. Dual-energy subtraction is not sensitive to the motion induced artifacts which often mar time subtraction images. While the time subtraction images had varying degrees of misregistration artifacts, none of the dual-energy studies contained significant misregistration artifacts. Densitometrically determined ejection fractions measured with and without correction for background signals were compared. Poor agreement between time subtraction ejection fractions determined with and without background correction (EF _NO-BKG =0.88 EF _BKG –6.0%, SEE=8.1%, r=0.83) demonstrated the sensitivity of time subtraction EFs to the performance of a background correction procedure. Conversely, densitometric measurement of ejection fraction using dual-energy subtraction was significantly less sensitive to the performance of a background correction (EP _NO-BKG =0.99 EF _BKG –5.3%, SEE=4.3%, r=0.96). Since background correction requires accurate definition of ventricular borders, but motion artifacts often preclude accurate border definition, it is concluded that dual-energy subtraction is a significantly more robust method for measuring left ventricular ejection fraction using densitometry. It is further concluded that identification of the systolic endocardial border is not required when performing densitometric EF measurements on dual-energy images. Drawing of the end-diastolic border alone is sufficient to produce an accurate ejection fraction measurement.This work was supported in part by Grant R01 HL38409 from the National Heart, Lung, and Blood Institute, Bethesda, Maryland.     

Use of intravenous digital subtraction ventriculography in the evaluation of left ventricle volumes and ejection fraction

Although intravenous digital subtraction ventriculography (IDSV) is increasingly used to estimate end-diastolic left ventricular volume (EDV), end-systolic left ventricular volume (ESV) and left ventricular ejection fraction (EF), its ability to reproduce the precise estimates provided by left ventricle cineangiography (LVCA) and its role in clinical cardiology have not been unequivocally established. In 32 patients subjected to cardiac catheterization for a variety of cardiac disorders and a normal or reduced left ventricular function the EDV, ESV and EF provided by a 30 degrees right anterior oblique LVCA were compared with those provided by a 30 degrees right anterior oblique IDSV. The mean EDV, ESV and EF obtained by IDSV in the 32 patients were superimposable on those obtained by LVCA. The individual EDV, ESV and EF values provided by the two methods were all related in a close linear fashion. For EF the correlation coefficient was 0.98 and the 90% confidence interval of the mean difference between the two series of values was +/- 6.1%, i.e. +/- 10% error compared to the mean EF provided by LVCA. Thus IDSV is a reliable and not too invasive method for estimating left ventricle volumes and ejection fraction. It might provide serial estimations with a better assessment of the evolution of a patient's disease and the effect of treatment.     

Diverging effects of postextrasystolic potentiation on left ventricular segmental wall motion in coronary heart disease

The effects of postextrasystolic potentiation (PESP) on regional left ventricular (LV) wall motion were evaluated in 40 coronary artery disease (CAD) patients. Of the 40 CAD patients, 20 had a prior myocardial infarction and 20 had a history of angina pectoris. PESP was obtained by applying programmed atrial stimulation during LV angiography, in a way that basal cycle length, premature beat, and postextrasystolic pause were almost identical in all patients. Segmental wall motion was evaluated by calculating regional ejection fraction (EF) of 5 different areas with a computerized method before and after the premature beat. The results were compared to those obtained in a group of 8 normal subjects. LV areas were classified as normokinetic, mildly hypokinetic, severely hypokinetic, and hyperkinetic, on the basis of their regional EF in respect to normals, and classified as "responder" (R) and "nonresponder" on the basis of the magnitude of the increase of regional EF with PESP. Of a total of 200 areas 129 were normokinetic (68% R), 45 were mildly hypokinetic (78% R), 17 severely hypokinetic (76% R), and 9 were hyperkinetic (78% R). Infarcted patients had a higher percentage of hypokinetic areas in basal conditions (p less than 0.001), however, the percentage of hypokinetic areas that responded to PESP was not significantly different from noninfarcted patients. In CAD patients, as a whole, a significant direct correlation was found between basal regional EF and regional EF after PESP (r = 0.88, p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

A comparison of conventional contrast ventriculography and digital subtraction ventriculography

We studied 46 patients with a history of transmural myocardial infarction or angiographic evidence of coronary artery stenosis with both conventional contrast ventriculography and digital subtraction ventriculography from May to September 1982. Urografin 76, 30 ml, was administered at a flow rate of 18 ml/s, by means of a catheter in the superior vena cava during digital subtraction ventriculography (DSV). Results of the latter were compared with conventional contrast ventriculograms. The correlation coefficient was r =0.938 (p less than 0.001) for determination of ejection fraction with both methods. The data in individual cases suggest that DSV is more sensitive than conventional contrast ventriculography in determination of severely reduced ejection fractions. The methods are practically identical in qualitative evaluation of disorders of regional wall motion in the anterolateral region, while DSV is more sensitive than conventional ventriculography in evaluating the apical region. Sensitivity was 85.7% when the two methods were compared in evaluation of the inferior region of the left ventricle. Both methods are identical in demonstration of severely deformed ventricles. Digital subtraction ventriculography may replace conventional contrast ventriculography in some of the situations discussed above.     

Diagnosis of left atrial tumors by coronary angiography and left ventriculography

The left ventriculograms and pulmonary and coronary angiograms of eight patients with left atrial (LA) tumors were reviewed. The patients' ages ranged from 52 to 65 years. In each case the tumor was outlined during left ventriculography. Coronary arteriography allowed visualization of tumor vessels in six cases (six of seven myxomas). Two of the patients had significant coronary obstructions. It is concluded that a left ventriculogram is a sensitive diagnostic test for the presence of LA tumors. Coronary arteriography is indicated in patients with LA tumors in this age group and is likely to provide independent evidence of the presence of an LA tumor.     

Comparison of radionuclide angiography with three echocardiographic parameters of left ventricular function in patients after myocardial infarction

Aims. Left ventricular function is an important outcome measure in patients with coronary artery disease, in particular in patients after myocardial infarction. It is reliably assessed by radionuclide angiography, but echocardiographic wall motion scoring might be an attractive alternative. Methods. Four days after reperfusion therapy for acute myocardial infarction both radionuclide angiography and echocardiography were performed in 90 patients. Segmental wall motion scoring (WMSI) and visual estimation of the left ventricular ejection fraction (LVEF) was done by 2 independent observers. Repeated analysis was performed 1 month after the first reading. In 41 patients the LVEF was assessed quantitatively by tracing of endocardial outlines of the left ventricle. Results. Both correlation with radionuclide angiography (estimated LVEF: r = 0.71, WMSI: r = – 0.68, Tracing: r = 0.59) and inter- and intra-observer variability (estimated LVEF: 19% and 15%, WMSI: 65% and 59%) were in favour of the LVEF estimation method. Correlation with radionuclide angiography measurements was related to the quality of the echocardiogram and to the extent of coronary artery disease. Conclusion. Simple echocardiographic estimation of left ventricular ejection fraction in patients after reperfusion therapy for acute myocardial infarction proved to be superior to quantitative assessment of ejection fraction and to segmental wall motion scoring in comparison with radionuclide angiography.     

Left ventricular function and wall thickness in long-term insulin-dependent diabetes mellitus: an echocardiographic study

Left ventricular function and wall thickness were evaluated in 111 type I diabetic subjects (mean age 25.5 +/- 9 years, mean duration of diabetes 13.4 +/- 6.2 years), using 2-D-derived M-mode echocardiography. Patients were carefully selected for the absence of major coronary risk factors or manifest cardiac disorders, and compared with 91 age- and sex-matched control subjects. Fractional shortening and the maximal velocity of cirumferential fibre shortening did not differ significantly between the two groups. Furthermore, no differences were found in the diastolic functional parameter of velocity of circumferential fibre extension. Posterior wall thickness was significantly increased in the diabetic patients compared to the controls (9.5 +/- 1.8 mm vs. 8.4 +/- 1.3 mm. P less than 0.01). As the thickness of the interventricular septum was also moderately increased (9.2 +/- 2.2 mm vs. 8.9 +/- 1.7 mm, NS), these findings provide evidence for an early structural change of the myocardium in young diabetic patients without clinically relevant functional consequences.     

急性心肌梗死患者室壁运动及心功能损害与发病-超声检查时间的关系

目的 探索急性心肌梗死患者室壁运动及心功能损害与发病-超声检查时间的关系.方法 收集初发急性心肌梗死患者219例,均已排除陈旧性心肌梗死、早期心肌再梗死、严重的瓣膜性心脏病、先天性心脏病、心肌病等影响室壁运动及心功能的疾病.所有患者均在予冠状动脉介入干预前行经胸超声心动图检查,采用二维超声等方法测量或（和）计算左心室舒张末期内径（left ventricular diameters in diastasis,LVDd）、收缩末期内径（left ventricular diameters in systole,LVDs）、左心室射血分数（left ventricular ejection fraction,LVEF）、室壁运动计分指数（wall motion index,WMI）及运动正常节段（fragments with normal wall motion,FM）百分比等参数,并精确记录发病-超声检查时间.结果 WMI、LVDd、LVDs、LVEF、FM百分比与发病-超声检查时间的相关关系均有统计学意义（P＜0.05）,相关系数分别为0.167,0.235,0.258,-0.196,-0.144.在WMI的多重线性回归分析结果显示,变量FM百分比、LVEF、左回旋支和（或）右冠状动脉进入方程（R2=0.878,justed R2=0.876）,偏回归系数分别为-1.103,-0.030,-0.001.结论 对于未予冠状动脉介入干预的急性心肌梗死患者,其室壁运动及心功能均随发病-超声检查时间的增加而减弱.     

Giant pedunculated thrombus with normal left ventricular systolic function mimicking myxoma

A 74-year-old woman with a history of essential thrombocythemia was admitted to the Coronary Care Unit because of atypical chest pain. The transthoracic echocardiogram showed normal left ventricular (LV) diameter and preserved regional and global systolic function. A pedunculated mobile mass measuring 25 mm × 14 mm was visualized in the LV cavity, attached to the midanterior wall. Because of the typical echocardiographic appearance, a myxoma was suspected. The patient evolved with left hemiparesis and negative T-waves in the electrocardiogram. Left ventriculotomy with excision of the ventricular mass was performed. Histopathological examination revealed an organized thrombus.     

Noninvasive assessment of systolic and diastolic left ventricular function in female runners

Nine female runners and 9 matched control subjects were investigatedwith echocardiography and Doppler velocimetry to assess cardiacstructure and systolic and diastolic left ventricular (LV) functionat rest. LV mass was considerably larger in the athletes (171vs 123 g; P <001). Minute distance, the Doppler index cardiacoutput, was similar in runners and controls; the lower heartrate (P<0.01) of the athletes was associated with a higherstroke distance (P<0.05). The latter could be attributedto a larger end-diastolic LV internal diameter (46 vs 43 mm;P<0.05); wall stress and the various indices of systolicLV function were not different between runners and controls.Early diastolic LV function, estimated from the velocity ofLV relaxation and the LV inflow pattern, and late diastolicfunction, assessed by Doppler velocimetry, were similar in runnersand controls. The unchanged ratio of the peak velocities ofLV filling during atrial contraction and early filling (0.49vs 0.44; NS) indicates that LV distensibility is unaltered inthe athletes.In conclusion, the higher left ventricular massof female runners is not associated with changes of systolicand diastolic LV function.     

Noninvasive assessment of systolic and diastolic left ventricular function in female runners

Nine female runners and 9 matched control subjects were investigatedwith echocardiography and Doppler velocimetry to assess cardiacstructure and systolic and diastolic left ventricular (LV) functionat rest. LV mass was considerably larger in the athletes (171vs 123 g; P <001). Minute distance, the Doppler index cardiacoutput, was similar in runners and controls; the lower heartrate (P<0.01) of the athletes was associated with a higherstroke distance (P<0.05). The latter could be attributedto a larger end-diastolic LV internal diameter (46 vs 43 mm;P<0.05); wall stress and the various indices of systolicLV function were not different between runners and controls.Early diastolic LV function, estimated from the velocity ofLV relaxation and the LV inflow pattern, and late diastolicfunction, assessed by Doppler velocimetry, were similar in runnersand controls. The unchanged ratio of the peak velocities ofLV filling during atrial contraction and early filling (0.49vs 0.44; NS) indicates that LV distensibility is unaltered inthe athletes.In conclusion, the higher left ventricular massof female runners is not associated with changes of systolicand diastolic LV function.