Reproducibility and comparison of cardiac output measurement by transthoracic bioimpedance and thermodilution methods in critically ill patients.

The short-term reproducibility in cardiac output (CO) and stroke volume (SV) measurements by transthoracic electrical bioimpedance (TEB) and thermodilution (TH) and their agreement were studied in 31 consecutive patients in the Intensive Care Unit (ICU). For comparison of changes in CO and SV, six patients were studied separately. TEB data were not obtainable in four patients due to interference with impedance signals or heart rate detection. Both methods were reproducible. For TEB, the mean difference of duplicate measurements was 0.03 (SD 0.3) l/min for CO and 0.3 (SD 3.2) ml for SV. For TH, it was -0.04 (SD 0.5) l/min for CO and 0.6 (SD 6.6) ml for SV. The coefficient of reproducibility for CO was thus 0.6 l/min for TEB and 1.0 l/min for TH and that for SV was 6.4 ml for TEB and 13.2 ml for TH. There was no agreement in absolute CO or SV between the methods; TEB giving lower absolute readings. The mean difference (TH-TEB) was 1.4 (SD 1.4) l/min for CO and 14 (SD 13.4) ml for SV. There was, however, good correlation between the two methods. For CO, the regression equation was TEB=0.623+0.739 (TH); (p less than 0.0005, r=0.87). For SV, the regression equation was TEB=-0.23+0.823 (TH); (p less than 0.0005, r=0.86). When only changes were considered, the mean difference (TH-TEB) was -0.5 (SD 0.9) l/min for CO and -4 (SD 8) ml for SV. There was significant correlation in the changes detected by each method.(ABSTRACT TRUNCATED AT 250 WORDS)     

胸阻抗无创血流动力学监测在危重患者的应用研究

目的评价胸阻抗（TEB）无创血流动力学监测在危重患者的应用价值。方法选取2006年10月至2007年8月入住本院综合ICU住院时间超过24h的危重患者48例,所有病例在常规监护基础上进行TEB监测,并在此期间行超声心动图检查,对两种方法同时测得的心输出量（CO）、心脏指数（CI）、每搏播出量（SV）、每搏指数（SI）等结果进行相关性分析。结果TEB法与超声心动图法所测得的CO、CI、SV和SI均具有很好的相关性。结论 TEB法与超声心动图法监测结果有很好的相关性;TEB法可用于危重患者的血流动力学监测。     

Bioimpedance Cardiac Output Measurements in Patients with Presumed Congestive Heart Failure

Objective: To describe preliminary ED experience with thoracic electrical bioimpedance (TEB) for evaluation of patients with complaints suggestive of congestive heart failure (CHF).
Methods: A 6-month, prospective, observational study was performed using a convenience sample of patients with signs and symptoms consistent with CHF. Patients were excluded if they had received medication prior to arrival in the ED, if they were obese, and if they had unstable vital signs. They also were excluded if they were combative, refused to sign consent, or had invasive lines that did not allow for TEB lead placement. Patients also were excluded if the study could not be completed because the patient was taken from the department for a diagnostic test, or if there were no good follow-up records available 6–12 months after the patient's visit. The patient's physician was blinded to the output of the TEB monitor. Cardiac output (CO), stroke volume (SV), end-diastolic volume (EDV), thoracic fluid index (TFI), and acceleration index (ACI) were recorded at 5-minute intervals. Results were evaluated for the time intervals 0–5 minutes, 30–35 minutes, and 60–65 minutes.
Results: Seven patients were included in the study. The echocardiographic diagnoses were hypertrophic car-diomyopathy (2 cases), dilated cardiomyopathy (2 cases), ischemic cardiomyopathy (1 case), right ventricular hypertrophy (1 case), and pericardial effusion (1 case). Significant changes were seen in all cardiac parameters, with variance from individual to individual.
Conclusions: Significant differences in TEB variables exist between patients who appear similar on initial examination in the ED. Changes noted on TEB may help to further elucidate physiologic differences. The clinical use of TEB-based hemodynamic measurements to guide presumed CHF patient management remains speculative.     

应用胸腔阻抗法评估手术和麻醉对患者血流动力学的影响

目的　通过无创心排血量监测仪 ,评价手术和麻醉对腹部择期手术患者血流动力学的影响。方法　应用 He Mo 6 0 1生物阻抗系统 ,分别于术前 1d、术后 4～ 6 h和 2 4 h对 32例腹部择期手术患者进行血流动力学监测 ,并比较心排血量 (CO)、心排指数 (CI)、每搏心排血量 (SV)、每搏心脏做功 (SW)、心脏每分做功(CW、)左室舒张末压 (L VEDP)和心率 (HR)的变化。结果　 CO、CI、CW和 L VEDP在术后 2 4 h内的改变与术前比较均无显著性差异 (P均 >0 .0 5 )。术后 4～ 6 h的 SV和 SW比术前有明显降低 (P均 <0 .0 5 ) ,而术后 2 4 h的 SV和 SW与术前相比则无显著性差异 (P均 >0 .0 5 )。术后 4～ 6 h HR明显快于术前 (P<0 .0 5 ) ,但术后 2 4h HR与术前相比无显著性差异 (P>0 .0 5 )。结论　术后 4～ 6 h SV和 SW值的降低可能与麻醉使心肌收缩力减弱有关 ,HR明显增快则是 SV和 SW降低后机体产生代偿机制的结果。最大程度地保证术中及术后充足的输液量 ,对维持 CO、CI以及维护组织血液灌注具有重要意义。     

Noninvasive Cardiac Output Measurement by Transthoracic Electrical Bioimpedence: Influence of Age and Gender

Background  Thoracic electrical bioimpedance (TEB) as a method of measuring cardiac output (CO) is being explored increasingly over the last two decades, as a non-invasive alternative to the pulmonary artery catheter. The objective of this study was to establish normative data for measurement of CO by TEB and define the effect of age and gender on CO. Method  Stroke volume (SV) of 397 normal individuals (203 men, 194 women) in the age range of 10–77 years was determined using Kubisek and Bernstein formulae by TEB method. Derived cardiac parameters including CO, cardiac index (CI), systemic vascular resistance and resistance index were calculated and analyzed. Results  We found significant difference in CO among age groups and between gender. CO between Kubicek formula and Bernstein formula correlated well, but their means differed significantly. Cardiac indices peak in the third and seventh decade and were comparable between genders. Conclusion  A comprehensive data set of normalized values expressed as 95% confidence interval and mean ± SD in different age groups and different gender was possible for cardiac parameters using TEB. Sathyaprabha TN, Pradhan C, Rashmi G, Thennarasu K, Raju TR. Noninvasive cardiac output measurement by transthoracic electrical bioimpedence: influence of age and gender.     

Continuous noninvasive real-time monitoring of stroke volume and cardiac output by thoracic electrical bioimpedance

Thoracic electrical bioimpedance (TEB) is a noninvasive method for the estimation of left ventricular stroke volume (SV). Objections to TEB in the past have included systematic overestimation of SV and cardiac output in normals, poor correlation in absolute terms with standard cardiac output reference techniques, motion and ventilation artifacts which distorted recorded waveforms except when patients remained in apnea during measurements, and lack of a computer to yield rapid heat-to-beat quantitation of SV and cardiac output. The present study entails real-time, beat-to-beat cardiac output determinations using TEB and assessing its agreement via a digital computer against a reference standard, thermodilution. A correlation coefficient of 0.88 is reported with 85% of data points falling within 20% confidence limits on either side of the line of identity.     

心肌存活性对状动脉旁路移植术左心整体功能的影响

探讨行冠状动脉旁路移植术的冠心病患者术前运动异常心肌的收缩功能储备对术后左心整体功能的影响。方法超声心动图连续观察６５例冠心病患者术前静脉态、小剂量多巴酚丁胺「５－１０μ／（ｋｇ．ｍｉｎ）」和术后的左心功能改变。结果有收缩功能储备组（Ⅱ组）的ＥＤＶ、ＥＤＶＩ、ＥＳＶ、ＥＳＶＩ明显高于无收缩功能储备组（Ⅰ组）（Ｐ〈０．０,１ＥＦ明显低于Ⅰ组。ＬＤＤＳＥ时Ⅰ组的ＥＳＶ、ＥＳＶＩ明显减少,ＥＦ、ＳＶ、Ｃ     

Non-invasive Cardiac Output by Transthoracic Electrical Bioimpedence in Post-cardiac Surgery Patients: Comparison with Thermodilution Method

OBJECTIVE: Thoracic electrical bioimpedance (TEB) cardiac output (CO) is being explored increasingly as a non-invasive alternative to the pulmonary artery catheter (PAC). This study compared TEB-CO measured using a new instrument - NICOMON (Larsen & Toubro Ltd. India) with thermodilution (Td) CO in post-cardiac surgery patients. METHODS: Postoperative cardiac surgical patients requiring a PAC for their management were studied. TEB-CO was measured by passing a 4 mA RMS alternating current across the chest and measuring the analog bioimpedence across the thorax. Kubicek equation was used to estimate TEB-CO. Td-CO was measured using a PAC. Bland-Altman analysis was used to compare paired data. RESULTS: One hundred and ninety-seven pairs of CO measurements were made by the two methods among 35 patients. Mean TEB-CO was 5.15 +/- 1.27 l/min and mean Td-CO was 5.22 +/- 1.28 l/min. Pearson correlation coefficient (r) for these measurements was 0.856 (P < 0.01), with bias -0.0651 l and precision: +/-1.37 l/min. The percentage error of measurement of this precision was 26.44%. Cardiac index also correlated among the two methods (r = 0.789; P = 0.01). CONCLUSIONS: Thoracic electrical bioimpedance cardiac output compares favorably with thermodilution method among post-cardiac surgery patients. Further studies are indi- cated with this instrument to validate its efficacy in various clinical situations and utility in monitoring hemodynamic interventions.     

Comparison of measurements of cardiac output by bioimpedance and thermodilution in severely ill surgical patients

In order to evaluate a new thoracic electrical bioimpedance (TEB) system for measurement of stroke volume based on the Sramek-Bernstein equation, 391 paired values of cardiac output were measured simultaneously with the standard thermodilution method. These values were obtained from 16 patients selected for having the most severe illness during a 6-month period; the intent was to evaluate the bioimpedance method in the worst possible situations. The correlation coefficient (r) was 0.83, slope was 0.87, intercept was 1.53, and the mean difference between the two methods was 16.2 +/- 11.8 (SD)% in the total series. In 285 paired samples where satisfactory conditions were met, r was 0.90, slope was 0.98, intercept was 0.34, and the mean difference was 11.8 +/- 8.9%. The data indicate satisfactory correlations between these two methods. When the TEB waveform is satisfactory, the agreement between TEB and thermodilution is as good as the agreement between serial thermodilution methods. Difficulties may arise with dysrhythmias, tachycardia (heart rate greater than 150 beat/min), metal in the chest or chest wall, sepsis, hypertension, and extremely oily skin. Mechanical ventilation did not appear to be a problem.     

Changes in blood pressure and cardiac output during maximal isokinetic exercise.

This study was undertaken to determine the blood pressure (BP) and cardiac output (Qc) responses to maximal isokinetic exercise. The subjects (n = 5) performed unilateral knee extension/flexion exercise (knee exercise) and unilateral elbow extension/flexion exercise (elbow exercise) at 0.52, 1.57, and 2.62 rads.sec-1. The BP was monitored using a cannula placed in the radial artery. Heart rate (HR), stroke volume (SV), and Qc were measured by impedance cardiography. In response to isokinetic exercise, HR and Qc increased significantly (p less than .01), while the SV did not. The BP response was characterized by significant increases in systolic, diastolic, and mean arterial pressure (MAP) (p less than .01). The Qc and MAP, responses were not influenced by the exercise velocity. The adjustments in HR, MAP, and rate pressure product (RPP) to the elbow exercise were qualitatively similar to those seen during the knee exercise, but the absolute values achieved were smaller (p less than .05). Compared with maximal dynamic exercise, the HR and SV responses to the knee exercises were lower. The MAP response to isokinetic exercise equaled the highest value achieved during dynamic exercise. Findings from the present study suggest that the cardiovascular stress (the increase in HR, MAP, and RPP) associated with isokinetic exercise is independent of the velocity of movement and is proportional to the active muscle mass.     

不同运动时长易筋经锻炼对健康老年人心脏功能的影响

目的:观察不同运动时长易筋经锻炼对健康老年人心脏形态结构、左心室泵血功能、左心室收缩功能的影响.方法:健康老年人58例分为A组30例和B组28例,A组和B组成员每次分别练习10min和20min的易筋经十二式.锻炼前后检测心脏功能,包括左心室收缩末期内径(ESD)、左心室舒张末期内径(EDD)、左心室舒张末期容量(EDV)、每搏输出量(SV)、每分输出量(CO)、心脏指数(CI)、射血分数(EF)以及短轴收缩率(FS).结果:锻炼12周后,心脏功能检测显示,2组EDV、EDD、SV、CI、EF、FS等各项指标均较锻炼前增加,而ESD有一定程度的下降,其中B组SV、CI、EF锻炼前后差异具有统计学意义(P＜0.05);锻炼后2组间各项指标比较差异无统计学意义.结论:2组运动时长均对心脏的形态结构产生一定的变化趋势,20min运动时长可使左心室的泵血功能显著改善,但收缩功能无显著变化.从改善心脏功能方面考虑,20min运动时长值得推荐.     

Electrophysiologic principles and theory of stroke volume determination by thoracic electrical bioimpedance

Thoracic electrical bioimpedance (TEB) is a harmless, noninvasive, user-friendly technology with wide patient acceptance. Stroke volume (SV) determination is important because it helps to define oxygen transport. Measurement of SV by TEB is rooted in concrete, basic electrical theory, as well as in theoretical models of electrical behavior of the human thorax and great thoracic vessels. This article is concerned with basic electrical theory as applied to TEB, signal acquisition, and the origin of the thoracic cardiogenic impedance pulse (delta Z). The appendix of the chapter features a more extensive overview of alternating current theory as applied to electrical bioimpedance.     

Methods of estimating cardiac output in the field

Simultaneous estimation of cardiac output (CO) by thoracic electrical bioimpedance (TEB) and thermodilution (TD) confirmed the results of a previous study which showed good agreement between these methods in selected, principally non-septic, patients. Poor agreement was found between simultaneous TEB and oesophageal Doppler monitoring (ODM) estimates of baseline and acute changes in CO. Taken with the results of previous studies, this implies that although isolated ODM estimates of CO, which tend to underestimate, are less reliable, ODM is the preferred method to monitor acute changes in CO. For many reasons, not least the speed with which a large number of seriously injured soldiers could be assessed, ODM is probably the better method if a non-invasive estimate of CO is required in field hospitals.      

Balloon pulmonary angioplasty improves interventricular dyssynchrony in patients with inoperable chronic thromboembolic pulmonary hypertension: a cardiac MR imaging study

To use cardiac magnetic resonance imaging (MRI) to investigate the effect of balloon pulmonary angioplasty (BPA) on interventricular dyssynchrony and its associations with ventricular interaction, which impairs LV function in patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH). This prospective observational study was approved by our institutional review board. Cardiac MRI and right heart catheterization were conducted before BPA sessions and at the follow up after BPA in 20 patients with CTEPH. We measured right ventricular (RV) and left ventricular (LV) end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), and ejection fraction (EF) using MRI. For the LV and RV free walls, the time to peak (T_peak) of circumferential strain was calculated as a parameter for interventricular dyssynchrony. Following BPA, the RV-EDV and -ESV were significantly decreased, and the RVEF was significantly increased. Conversely, BPA led to significantly increased LV EDV and SV without changing LVESV. The left-to-right free wall delay (L–R delay) in T_peak strain decreased from 105?±?44 ms to 47?±?67 ms (p?<?0.001). Increased LV EDV (r?=?0.65, p?<?0.01), SV (r?=?0.74, p?<?0.001) and 6-minute walk distance (6MWD) (r?=?0.54, p?<?0.05) were correlated to the reduction in L–R delay. In patients with inoperable CPEPH, BPA improved interventricular dyssynchrony, which was strongly associated with increased SV and 6MWD. The assessment of interventricular dyssynchrony using cardiac MRI has an important role in evaluating ventricular interaction, which reduces LVSV and exercise tolerance.     

Determination of cardiac output during positive end-expiratory pressure--noninvasive electrical bioimpedance compared with standard thermodilution

Many investigators have demonstrated the accuracy and reliability of thoracic electrical bioimpedance (TEB) in spontaneously breathing patients and under mechanical intermittent positive-pressure ventilation. Most of these studies showed a good correlation between TEB and invasive methods, such as thermodilution (TD) or the Fick method. But during PEEP, contrary results occur when comparing TEB and TD. In six patients undergoing neurosurgical interventions, TEB cardiac output measurements were compared during zero end-expiratory pressure (ZEEP) and during PEEP at 8 cm H2O with a low respiratory rate. The data revealed a good correlation during ZEEP (r = .93) and during PEEP (r = .91). There was no significant statistical difference when measuring cardiac output by TEB during ventilation with PEEP. During normal or decreased cardiac output, TEB overestimated cardiac output compared with TD, whereas TEB underestimated cardiac output compared with TD during increased cardiac output, especially during PEEP.     

Effect of hemodialysis on left ventricular function. Dissociation of changes in filling volume and in contractile state

Prior studies of the effect of hemodialysis on left ventricular function have not distinguished between the removal of uremic toxins and the change in cardiac filling volume. To separate these effects, left ventricular function was examined by serial echocardiography in five stable hemodialysis patients before and after three different dialysis procedures: (a) hemodialysis with volume Loss, (b) ultrafiltration (volume loss only), and (c) hemodialysis without volume loss. The patients were similarly studied under control conditions and after increased (5 degrees of head-down tilt for 90 min) and decreased (lower body negative pressure) cardiac filling volume. After hemodialysis with volume loss, end-diastolic volume (EDV) decreased from 167 to 128 ml (P less than 0.001) and end-systolic volume (ESV) decreased from 97 to 51 ml (P less than 0.001) without a change in stroke volume (SV). Ejection fraction increased from 42 to 52% (P less than 0.001) and mean velocity of circumferential fiber shortening (VCF) increased from 0.61 to 1.04 circumferences (circ)/s (P less than 0.001). After ultrafiltration, EDV decreased from 167 ml to 124 ml (P less than 0.001) and SV from 73 ml to 39 ml (P less than 0.001), without significant changes in ESV or VCF. In contrast to the maneuvers in which volume loss occurred, after hemodialysis without volume loss ESV decreased from 95 to 66 ml (P less than 0.001) and SV increased from 74 ml to 97 ml (P less than 0.001) without changes in EDV. EF increased from 44 to 59% (P less than 0.001) and VCF increased from 0.64 to 1.26 circ/s (P less than 0.001). Ventricular function curves plotted from data obtained under conditions of altered cardiac filling volume before and after the three dialysis maneuvers demonstrate that ultrafiltration produced a pure Frank-Starling effect, while hemodialysis with or without volume loss produced a shift in the ventricular function curves, which demonstrated an increase in the contractile state of the left ventricle. The changes in left ventricular function produced by regular hemodialysis are the combined effects of a decrease in EDV and an increase in the contractile state of the left ventricle.     

Presence of mechanical dyssynchrony in duchenne muscular dystrophy

Background

There are physiological reasons for the effects of positioning on hemodynamic variables and cardiac dimensions related to altered intra-abdominal and intra-thoracic pressures. This problem is especially evident in pregnant women due to the additional aorto-caval compression by the enlarged uterus. The purpose of this study was to investigate the effect of postural changes on cardiac dimensions and function during mid and late pregnancy using cardiovascular magnetic resonance (CMR).

Methods

Healthy non-pregnant women, pregnant women at 20^th week of gestation and at 32^nd week of gestation without history of cardiac disease were recruited to the study and underwent CMR in supine and left lateral positions. Cardiac hemodynamic parameters and dimensions were measured and compared between both positions.

Results

Five non-pregnant women, 6 healthy pregnant women at mid pregnancy and 8 healthy pregnant women at late pregnancy were enrolled in the study. In the group of non-pregnant women left ventricular (LV) cardiac output (CO) significantly decreased by 9% (p = 0.043) and right ventricular (RV) end-diastolic volume (EDV) significantly increased by 5% (p = 0.043) from the supine to the left lateral position. During mid pregnancy LV ejection fraction (EF), stroke volume (SV), left atrium lateral diameter and left atrial supero-inferior diameter increased significantly from the supine position to the left lateral position: 8%, 27%, 5% and 11%, respectively (p < 0.05). RV EDV, SV and right atrium supero-inferior diameter significantly increased from the supine to the left lateral position: 25%, 31% and 13% (p < 0.05), respectively. During late pregnancy a significant increment of LV EF, EDV, SV and CO was observed in the left lateral position: 11%, 21%, 35% and 24% (p < 0.05), respectively. Left atrial diameters were significantly larger in the left lateral position compared to the supine position (p < 0.05). RV CO was significantly increased in the left lateral position compared to the supine position (p < 0.05).

Conclusions

During pregnancy positional changes affect significantly cardiac hemodynamic parameters and dimensions. Pregnant women who need serial studies by CMR should be imaged in a consistent position. From as early as 20 weeks the left lateral position should be preferred on the supine position because it positively affects venous return, SV and CO.     

MRI-derived left ventricular function parameters and mass in healthy young adults: Relation with gender and body size

Purpose: To obtain normal values of left ventricular (LV) end-diastolic volume (EDV), stroke volume (SV), cardiac output (CO) and LV mass, in relation to gender, weight (W), length (L) and body surface area (BSA). Methods: Sixty-one healthy volunteers (32 male, 22.4 ± 2.2?years) were examined, weight was 70.9 ± 12.2?kg, length was 1.78 ± 0.09?m, BSA was 1.88 ± 0.19 m². Segmented k-space breathhold cine MRI was used to obtain a stack of parallel short-axis images, from which LV volumes and end-diastolic mass were derived by slice summation. Four different body size indices were studied: W, L, L² and BSA. Results: After indexing for L, L² and BSA, the gender differences in all LV parameters are still persisting. After indexing for W, gender differences persist for EDV and EDM, but are no longer observed for SV and CO. Separate regression analyses for males and females were performed. EDV, SV, CO and EDM correlated significantly with each body size index, both in males and in females. L or BSA were in general better predictors for LV parameters than W. Linear regression equations of EDV (ml) vs. L(m) were for males: EDV = 275 × L ? 359 and for females: EDV = 190 × L ? 215. Equations of SV(ml) vs. L were for males: SV = 186 × L ? 237 and for females: SV = 118 × L ? 121. Equations of LV mass(g) vs. L were for males: Mass = 175 × L ? 179 and for females: Mass = 65.8 × L ? 10.9. Conclusion: Most gender differences in LV parameters remain even after correction for body size indices. Normal reference values for LV parameters are given in relation to body size indices, by calculating regression coefficients separately for males and females. These normal values serve to obtain more accurate reference values for a patient with given gender, weight and length, and thus to improve the differentiation between normal and abnormal LV parameters.     

MRI对肥厚型心肌病左右心室整体功能变化的研究

目的利用磁共振电影成像技术探讨肥厚型心肌病患者左、右心室整体功能的变化。材料与方法连续收集自2013年2月至2014年2月在我院行心脏核磁共振检查的被拟诊为肥厚型心肌病的患者共26例,同期收集20例健康志愿者心脏核磁共振检查的图像。由两名放射科医师分别将26例肥厚型心肌病患者和20例健康志愿者的图像导入Report CARD3.6心脏功能分析软件进行相关数据测量,最终获得左、右心室的舒张末期容积(EDV)、收缩末期容积(ESV)、射血分数(EF)、每搏输出量(SV)以及左心室的短轴缩短率(FS)。肥厚型心肌病患者与健康志愿者之间左、右心室功能指标的比较采用独立样本t检验。结果肥厚型心肌病患者左心室整体功能的各项指标LVEDV、LVESV、LVEF、LVSV及FS分别为(88.94±13.29)ml、(24.75±7.31)ml、(71.70±7.60)%、(64.20±12.82)ml、(52.52±8.83)%,健康志愿者LVEDV、LVESV、LVEF、LVSV及FS分别为(107.93±12.62)ml、(34.18±3.6)ml、(67.25±4.48)%、(73.65±12.41)ml、(36.8±3.82)%,LVEDV、LVESV、LVSV数值较健康志愿者均减低,二者之间有显著性差异;LVEF较正常人增高,但没有显著性差异;FS较正常人显著增高,二者之间有显著性差异。肥厚型心肌病患者右心室整体功能各项指标RVEDV、RVESV、RVEF、RVSV分别为(88.48±17.67)ml、(29.84±7.50)ml、(6 4.6 5±1 0.2 7)%、(5 8.6 6±1 7.0 9)m l,健康志愿者RV E D V、RV E S V、RVEF、RVSV分别为(142.31±23.62)ml、(72.49±16.13)ml、(49.18±5.6)%、(69.82±13.43)ml,RVEDV、RVESV较正常人明显减低,二者之间有显著性差异;RVEF较正常人增高,二者之间有显著性差异;RVSV较正常人减低,二者之间没有显著性差异。结论在早期,肥厚型心肌病左心室舒张功能减低、收缩功能升高的同时,右心室的舒张功能也减低、收缩功能升高,左右心室的功能变化是一致的。     

实时三维超声心动图评价中晚孕期正常胎儿右心室功能

目的应用全容积实时三维超声心动图评价正常胎儿右心室功能。方法对109例孕妇的正常胎儿进行超声心动图检查．应用Shimazaki法、双平面Simpson法以及全容积实时三维超声心动图方法（RT-3DE）来评估胎儿右室舒张末期容积（EDV）、收缩末期容积（ESV）、每搏输出量（SV）、射血分数（EF）及心输出量（CO）,并比较三种方法获得的数值结果。结果三种方法比较,EDV、ESV、SV、CO值的差异均有统计学意义（F=31．22、23．30、31．67、32．61。P均〈0．05）,EF值的差异无统计学意义（F=1．56,P〉0．05）。RT-3DE法、双平面Simpson法与Shimazaki法比较,除EF值外,胎儿EDV、ESV、SV、CO值的差异均有统计学意义（t分别=6．57、5．64、6．66、6．76;7．10、6．25、7．11、7．21,P均〈0．05）;RT-3DE法与Simpson法比较,胎儿EDV、ESV、SV、CO的差异无统计学意义（t分别=0．53、0．61、0．44、0．45．P均〉0．05）。两个观察者一致性检验,RT-3DE法的Kappa值要高ff-Simpson法的Kappa值。结论全容积实时三维超声心动图能够全面、整体地评价胎儿右心室心功能。