Evaluation of the Clinical Utility of Transesophageal Echocardiography and Invasive Monitoring to Assess Right Ventricular Function During and After Pulmonary Endarterectomy.

OBJECTIVE: Patients undergoing pulmonary endarterectomy (PEA) have impaired right ventricular function. The authors sought to assess the clinical utility of commonly used perioperative echocardiographic and right heart catheter measurements in patients undergoing PEA. DESIGN: A single-center prospective observational study. SETTING: The study was conducted in a quaternary care cardiac surgical center in the United Kingdom. PARTICIPANTS: Patients undergoing PEA between April 2015 and January 2016. INTERVENTIONS: Thermodilution cardiac index and echocardiography variables were measured at 3 time points: before sternotomy (T1), after pericardial incision (T2), and after sternal closure (T3). Six-month follow-up echocardiography and 6-minute walk (6-MWT) test were performed. MEASUREMENTS AND MAIN RESULTS: Fifty patients were recruited and complete data sets were available for 41 patients. Tricuspid annular plane systolic excursion declined after pericardial incision and cardiopulmonary bypass (T1: 15 ± 4 mm, T2: 13 ± 4 mm, T3: 7 ± 2 mm; p < 0.0001), returning to baseline 6 months postoperatively. Cardiac index (T1: 2.5 ± 0.7 L/min/m2, T2: 2.6 ± 0.6 L/min/m2, T3: 2.3 ± 0.5 L/min/m2; p = 0.07) and right ventricular fractional area change (T1: 36 ± 11%, T2: 40 ± 12%, T3: 40 ± 9%; p = 0.12) were preserved perioperatively. 6-MWT improved from baseline (294 ± 111 m) to follow-up (357 ± 107 m) (p < 0.001). Pulmonary vascular resistance at T3 correlated moderately with follow-up 6-MWT (R = -0.60). CONCLUSIONS: In patients undergoing PEA, invasive measurements and echocardiography assessment of right ventricular function are not interchangeable. Tricuspid annular plane systolic excursion is not a reliable measure of right ventricular function perioperatively. Pulmonary vascular resistance shows moderate correlation with postoperative functional capacity.

Echocardiographic evaluation of systolic and diastolic function: a preoperative study of correlation with serum NT-proBNP.

OBJECTIVE: The authors hypothesized that preoperative N-terminal probrain natriuretic peptide (NT-proBNP) correlates well with longitudinal strain measurements and with Doppler measurements of diastolic function. DESIGN: Prospective observational study. SETTING: University teaching hospital. PARTICIPANTS: Forty patients undergoing elective cardiac surgery. INTERVENTIONS: Aortic valve replacement, coronary artery bypass grafting, or a combination of these procedures. MEASUREMENTS AND MAIN RESULTS: Plasma NT-proBNP concentration was obtained by analyzing blood samples with a commercially available kit. Left ventricular systolic function was assessed by speckle tracking ultrasound strain measurements and left ventricular diastolic function was assessed by 2 Doppler methods: E/A ratio and E/E' ratio. Tissue Doppler imaging velocities (E' and A') were measured in the basal septum (annular) and pulse-wave Doppler was used to measure mitral in-flow profile (E and A). The correlation between global strain data from the speckle tracking ultrasound measurement and NT-proBNP levels was ρ = 0.35 (p = 0.026). With a cutoff value of -15% in global strain measurements, there was a significant difference in NT-proBNP levels (117 v 57 pg/mL, p = 0.048). E/E' values correlated with NT-proBNP levels (ρ = 0.46, p = 0.011). With a cutoff of 15 in E/E' values, there were significant differences in corresponding NT-proBNP levels (33 v 113 pg/mL, p = 0.004). CONCLUSIONS: A correlation was found between plasma levels of NT-proBNP and speckle tracking ultrasound strain measurements by an easily employed method applicable in the anesthesia and preoperative settings. In addition, the well-established marker of diastolic function, E/E', correlated well with NT-proBNP, whereas the E/A ratio failed to show any association.

Learning curve for Doppler measurement of fetal modified myocardial performance index.

OBJECTIVE: To assess the learning curve for measurement of the fetal modified myocardial performance index (MPI). METHODS: Three trainees with the theoretical knowledge of but without prior experience in performing MPI measurement were selected. Each trainee and one experienced examiner measured MPI in a cohort of 90 consecutive fetuses. The average difference between the three trainees and the expert in the MPI measurements was calculated; a difference below 10% was considered to indicate an accurate measurement. Individual and averaged learning curves were delineated using cumulative sum analysis (CUSUM). RESULTS: The gestational age at evaluation ranged from 20 + 4 to 41 + 4 (mean, 33 + 3) weeks. The CUSUM plots demonstrated that, on average, competence in performing fetal MPI measurement was achieved by 65 cases. The average number of attempts to achieve competence were 42, 77 and 83 for the ejection time, isovolumetric contraction time and isovolumetric relaxation time, respectively. CONCLUSIONS: Evaluation of fetal MPI by an inexperienced trainee requires on average 65 measurements to achieve competence.

Current and evolving echocardiographic techniques for the quantitative evaluation of cardiac mechanics: ASE/EAE consensus statement on methodology and indications endorsed by the Japanese Society of Echocardiography.

Echocardiographic imaging is ideally suited for the evaluation of cardiac mechanics because of its intrinsically dynamic nature. Because for decades, echocardiography has been the only imaging modality that allows dynamic imaging of the heart, it is only natural that new, increasingly automated techniques for sophisticated analysis of cardiac mechanics have been driven by researchers and manufacturers of ultrasound imaging equipment. Several such techniques have emerged over the past decades to address the issue of reader's experience and inter-measurement variability in interpretation. Some were widely embraced by echocardiographers around the world and became part of the clinical routine, whereas others remained limited to research and exploration of new clinical applications. Two such techniques have dominated the research arena of echocardiography: (1) Doppler-based tissue velocity measurements, frequently referred to as tissue Doppler or myocardial Doppler, and (2) speckle tracking on the basis of displacement measurements. Both types of measurements lend themselves to the derivation of multiple parameters of myocardial function. The goal of this document is to focus on the currently available techniques that allow quantitative assessment of myocardial function via image-based analysis of local myocardial dynamics, including Doppler tissue imaging and speckle-tracking echocardiography, as well as integrated back- scatter analysis. This document describes the current and potential clinical applications of these techniques and their strengths and weaknesses, briefly surveys a selection of the relevant published literature while highlighting normal and abnormal findings in the context of different cardiovascular pathologies, and summarizes the unresolved issues, future research priorities, and recommended indications for clinical use.

A novel approach to standard techniques in the assessment and quantification of the interventricular systolic relationship.

BACKGROUND: Blood flow between the right and left ventricles is subject to the continuity equation and systolic ventricular interdependence. Quantification of this relationship might aid in understanding inter-ventricular function. The purpose of this study was to evaluate and quantify ventricular interdependence by directly comparing right and left ventricular systolic function though echocardiographic surrogates of right and left ventricular systolic function such as MAPSE, TAPSE, RV TVI and LV TVI. METHODS: This study prospectively evaluated 51 healthy participants (mean age, 41 ± 17 years) by resting echocardiography. In addition to standard measurements, tricuspid annular plane of systolic excursion, (TAPSE), mitral annular plane of systolic excursion (MAPSE), and the peak annulus systolic velocity of the right ventricular (RVs) and left ventricular (LVs) free walls were measured by M-mode and pulsed wave Doppler tissue echocardiography and further evaluated for variance across age, gender, and body surface area. RESULTS: TAPSE (22.1 ± 2.9 mm) was over 54.5% greater than MAPSE (14.3 ± 2.6 mm) and RVs was 64.4% greater than LVs. The LV to RV systolic relationship measured by MAPSE/TAPSE and LVs/RVs ratios were 0.66 ± 0.14 and 0.76 ± 0.21 respectively. These values were not significantly affected by age, gender or body surface area (BSA). CONCLUSION: MAPSE/TAPSE and LVs/RVs ratios appear stable across age, gender, and BSA potentially making them good surrogates of systolic ventricular relationship and interdependence.

Reference values of tissue Doppler imaging and pulsed Doppler echocardiography for analysis of left ventricular diastolic function in healthy adults.

To determine reference values for tissue Doppler imaging (TDI) and pulsed Doppler echocardiography for left ventricular diastolic function analysis in a healthy Brazilian adult population. Observations were based on a randomly selected healthy population from the city of Vitória, Espírito Santo, Brazil. Healthy volunteers (n = 275, 61.7% women) without prior histories of cardiovascular disease underwent transthoracic echocardiography. We analyzed 175 individuals by TDI and evaluated mitral annulus E'- and A'-waves from the septum (S) and lateral wall (L) to calculate E'/A' ratios. Using pulsed Doppler echocardiography, we further analyzed the mitral E- and A-waves, E/A ratios, isovolumetric relaxation times (IRTs), and deceleration times (DTs) of 275 individuals. Pulsed Doppler mitral inflow mean values for men were as follows: E-wave: 71 ± 16 cm/sec, A-wave: 68 ± 15 cm/sec, IRT: 74.8 ± 9.2 ms, DT: 206 ± 32.3 ms, E/A ratio: 1.1 ± 0.3. Pulsed Doppler mitral inflow mean values for women were as follows: E-wave: 76 ± 17, A-wave: 69 ± 14 cm/sec, IRT: 71.2 ± 10.5 ms, DT: 197 ± 33.3 ms, E/A ratio: 1.1 ± 0.3. IRT and DT values were higher in men than in women (P = 0.04 and P = 0.007, respectively). TDI values in men were as follows: E'S: 11± 3 cm/sec, A'S: 13 ± 2 cm/sec, E'S/A'S: 0.89 ± 0.2, E'L: 14 ± 3 cm/sec, A'L: 14 ± 2 cm/sec, E'L/A'L: 1.1± 0.4. E-wave/ E'S ratio: 6.9 ± 2.2; E-wave / E'L ratio: 4.9 ± 1.7. In this study, we determined pulsed Doppler and TDI derived parameters for left ventricular diastolic function in a large sample of healthy Brazilian adults.

Pulsed-wave tissue Doppler and color tissue Doppler echocardiography: calibration with M-mode, agreement, and reproducibility in a clinical setting.

BACKGROUND: Myocardial velocities can be measured with both pulsed-wave tissue Doppler (PWTD) and color tissue Doppler (CTD) echocardiography. We aimed to (A) to explore which of the two methods better approximates true tissue motion and (B) to examine the agreement and the reproducibility of the two methods in a routine clinical setting. METHODS: For Study A, the displacements of 63 basal myocardial segments from 13 patients were examined with M-mode and compared with the velocity-time integral of PWTD and CTD velocities. For Study B, the basal lateral segments from 58 patients were examined with PWTD and CTD, and the peak myocardial velocities during systole (Sm), early diastole (Em), and late diastole (Am) were measured. RESULTS: Study A: CTD-based measurements of displacement were 12% lower than M-mode measurements (95% CI: -18%; -6%). PWTD velocity-time integrals measured at the outer edge of the spectral band were 40% higher (33%; 46%) than M-mode measurements. Study B: PWTD measurements of myocardial velocity were systematically higher than CTD measurements: Sm 7.51 versus 5.54, difference 1.97 +/- 1.41 cm/sec; Em 8.74 versus 6.86, difference 1.88 +/- 1.70 cm/sec; Am 7.46 versus 5.17, difference 2.29 +/- 1.82 cm/sec; P < 0.001 for all. Intraobserver coefficient of variation for Sm, Em, and Am were 6%, 12%, and 12% for PWTD, 14%, 13%, and 20% for CTD. CONCLUSIONS: CTD measures numerically smaller tissue velocities than PWTD, mostly due to an overestimation of true tissue motion by PWTD. The methods have good agreement and comparable reproducibility.

Z-score reference ranges for pulsed-wave Doppler indices of the cardiac outflow tracts in normal fetuses.

To determine Z-score equations and reference ranges for Doppler flow velocity indices of cardiac outflow tracts in normal fetuses. A prospective cross-sectional echocardiographic study was performed in 506 normal singleton fetuses from 18 to 40 weeks. Twelve pulsed-wave Doppler (PWD) measurements were derived from fetal echocardiography. The regression analysis of the mean and the standard deviation (SD) for each parameter were performed against estimated fetal weight (EFW) and gestational age (GA), in order to construct Z-score models. The correlation between these variables and fetal heart rate were also investigated. Strong positive correlations were found between the twelve PWD indices and the independent variables. A linear-quadratic regression model was the best description of the mean and SD of most parameters, with the exception of the velocity time interval (VTI) of ascending aorta against EFW, which was best fitted by a fractional polynomial. Z-score equations and reference values for PWD indices of fetal cardiac outflow tracts were proposed against GA and EFW, which may be useful for quantitative assessment of potential hemodynamic alternations, particularly in cases of intrauterine growth retardation and structural cardiac defects.

Comprehensive echocardiographic assessment of biventricular function in the rabbit, animal model in cardiovascular research: feasibility and normal values.

Quantification of cardiac structure and function is central in cardiovascular research. Rabbits are valuable research models of cardiovascular human disease; however, there is little normal data available. The aim of this study was to investigate feasibility and provide normal values for comprehensive echocardiographic assessment of biventricular function in rabbits. New Zealand white rabbits underwent trans-thoracic echocardiography using a general electric (GE) Vivid 7/E9 system with a 10 MHz transducer, under light sedation, to evaluate biventricular function and dimensions. Images for two-dimensional, M-mode, tissue Doppler imaging (TDI) and speckle-tracking strain echocardiography were acquired and analysed. 55 male rabbits (sized matched with a newborn human baby) were studied, mean weight was 2.9 ± 0.23 kg. Adequate images were obtained in 90% for the left ventricle (LV) and 80% for the right ventricle (RV). Two-dimensional speckle-tracking strain was feasible in 60%. Average heart rate was 248 ± 36 beats per minute; LV ejection faction 72 ± 8.0; RV fractional area change 45.9 ± 9.0%; RV myocardial performance index 0.39 ± 0.35; tricuspid annular planar systolic excursion 0.60 ± 0.24 cm. LV TDI parameters were S' 8.6 ± 3.1 cm/s; E' 12.0 ± 4.46 cm/s. RV TDI parameters were S' 10.49 ± 3.18; E' 14.95 ± 4.64 cm/s. LV and RV global peak systolic longitudinal strain were -17 ± 5 and -22 ± 8%, respectively. Comprehensive investigation of biventricular dimensions and function by echocardiography is feasible in the rabbit. Apical views and strain imaging have lower feasibility. Normal values of LV and RV functional parameters are with comparable values to human children. Animal cardiovascular research is key to develop new goals in clinical practice.

Reported normal values and weighted means for commonly used echocardiography pulsed Doppler and tissue Doppler measurements.

Pulsed Doppler (PW) and tissue Doppler imaging (TDI) measurements are part of every echocardiography examination for evaluation of left ventricular (LV) diastolic function and filling pressure. The purpose of this study was to summarize published data on normal values for PW and TDI measurements. A PubMed search was performed on the 10th of October 2016 to identify relevant articles. Studies were considered relevant if they included more than 200 healthy individuals. A total of 13 studies were identified. Of these, 13 studies with 7777 subjects reported PW measurement over the mitral valve, six studies with 4082 subjects reported PW measurement in the pulmonary vein and 10 studies with 5988 subjects reported TDI. We also report weighted mean values for 14 different variables. As expected, measurements varied with age. There were no major differences between men and women. In contrast, there was a large difference in reported values between studies, in corresponding age groups. This review therefore raises caution about relying on normal values from just one study.

Evaluation of traditional and novel echocardiographic methods of cardiac diastolic dysfunction post radiotherapy in breast cancer.

BACKGROUND: To investigate alterations in left ventricular (LV) diastolic function using traditional and novel echocardiographic parameters, following radiation therapy (RT) in breast cancer patients in the acute setting. METHODS: 40 chemotherapy-naïve women with left-sided breast cancer undergoing RT were prospectively recruited. A comprehensive transthoracic echocardiogram (TTE) was performed at baseline, during RT and 6weeks post-RT. Traditional echocardiographic diastolic parameters and diastolic strain rate were measured and analysed. The relationship between alterations in diastolic parameters, changes in global longitudinal systolic strain (GLS) and radiation dose were investigated. RESULTS: Traditional diastolic parameters remained largely unchanged; however diastolic strain parameters, E-Sr and A-Sr were significantly reduced 6weeks post-RT [Longitudinal E-Sr (s-1) 1.47+/-0.32 vs 1.29+/-0.27*; Longitudinal A-Sr (s-1) 1.19+/-0.31 vs 1.03+/-0.24*; *p<0.05 vs baseline]. When patients were divided by a reduction ≥10% versus <10% in GLS post-RT, a greater reduction in both traditional diastolic and diastolic strain parameters was observed in the group with >10% reduction in systolic function as evaluated by GLS. When patients were divided by mean v30 dose, a greater % change in E-Sr was noted in those receiving more than mean V30 dose. CONCLUSION: Diastolic dysfunction was only evident acutely, post-RT with the use of newer methods like strain analysis. A significant reduction in diastolic function was seen in the patient subgroup with ≥10% reduction in systolic function, enhancing the notion of diastolic function as a potential indicator for systolic dysfunction. Future longitudinal studies are required to determine the specific prognostic value of these observations.

Reference Values and Z Scores for Pulsed-Wave Doppler and M-Mode Measurements in Fetal Echocardiography.

BACKGROUND: Fetal echocardiography is now the standard approach for detailed investigations of fetal cardiac anatomy and function. Available studies proposing reference values for pulsed-wave Doppler (PWD) measurements are often focused on few parameters. Furthermore, the methodology used for validating these proposed reference values is sometimes insufficiently described, and parameters necessary to compute Z scores are not always available. Improved definition of reference values with adequate statistical validation is needed for proper interpretation of PWD measurements in a clinical setting. In this study, the authors propose a comprehensive set of reference values and Z score equations for fetal PWD and M-mode measurements with thorough assessment of Z score quality and validity. METHODS: Women with normal singleton pregnancies between 18 and 39 weeks of gestational age were included. A set of 57 measurements was performed, including PWD, M-mode measurements, and calculation of systolic, diastolic, and global function indices. Several parametric regressions were tested to model each measurement against gestational age. The SD was also modeled to account for heteroscedasticity. Z score equations were computed, and the proposed reference values were tested for residual association, residual heteroscedasticity, and departure from the normal distribution. RESULTS: One hundred four uncomplicated singleton pregnancies with normal fetal hearts were included. Nonlinear relationships with gestational age were found for most measurements. Parametric normalization was successful for most measurements analyzed, and it was possible to compute Z score equations with minimal residual association with gestational age, no residual heteroscedasticity, and no significant departure from the normal distribution. CONCLUSIONS: The authors propose a comprehensive set of Z score equations for 57 fetal functional measurements, some of which do not have any published reference values. These Z score equations will allow echocardiographers to more accurately identify measurements that diverge from normal and thus detect earlier potential alterations in fetal heart function.

Reference values for pulse wave Doppler and tissue Doppler imaging in pediatric echocardiography.

BACKGROUND: In pediatric echocardiography, pulse wave Doppler, and tissue Doppler imaging velocities are widely used to assess cardiac function. Current reference values and Z scores, allowing adjustment for growth are limited by inconsistent methodologies and small sample size. Using a standardized approach for parametric modeling and Z score quality assessment, we propose new pediatric reference values and Z score equations for most left ventricular pulse wave Doppler and tissue Doppler imaging measurements. METHODS AND RESULTS: Two hundred thirty-three healthy pediatric subjects 1 to 18 years of age were prospectively recruited. Thirteen pulse wave Doppler and 14 tissue Doppler imaging measurements were recorded. Normalization for growth was done via a complete and standardized approach for parametric nonlinear regression modeling. Several analyses were performed to ensure adequate Z score distribution and to detect potential residual associations with growth or residual heteroscedasticity. Most measurements adopted a nonlinear relationship with growth and displayed significant heteroscedasticity. Compared with age, height, and weight, normalization for body surface area was most efficient in removing the effect of growth. Generally, polynomial and allometric models yielded adequate goodness-of-fit. Residual values for several measurements had significant departure from the normal distribution, which could be corrected using logarithmic or reciprocal transformation. Overall, weighted parametric nonlinear models allowed us to compute Z score equations with adequate normal distribution and without residual association with growth. CONCLUSIONS: We present Z scores for normalized pulse wave Doppler and tissue Doppler imaging in pediatric echocardiography. Further studies are needed to define the threshold beyond which health becomes a disease by integrating other important factors such as ventricular morphology, loading conditions, and heart rate.

The prognostic value of standardized reference values for speckle-tracking global longitudinal strain in hypertrophic cardiomyopathy.

Speckle-tracking left ventricular global longitudinal strain (GLS) assessment may provide substantial prognostic information for hypertrophic cardiomyopathy (HCM) patients. Reference values for GLS have been recently published. We aimed to evaluate the prognostic value of standardized reference values for GLS in HCM patients. An analysis of HCM clinic patients who underwent GLS was performed. GLS was defined as normal (more negative or equal to -16%) and abnormal (less negative than -16%) based on recently published reference values. Patients were followed for a composite of events including heart failure hospitalization, sustained ventricular arrhythmia, and all-cause death. The power of GLS to predict outcomes was assessed relative to traditional clinical and echocardiographic variables present in HCM. 79 HCM patients were followed for a median of 22 months (interquartile range 9-30 months) after imaging. During follow-up, 15 patients (19%) met the primary outcome. Abnormal GLS was the only echocardiographic variable independently predictive of the primary outcome [multivariate Hazard ratio 5.05 (95% confidence interval 1.09-23.4, p = 0.038)]. When combined with traditional clinical variables, abnormal GLS remained independently predictive of the primary outcome [multivariate Hazard ratio 5.31 (95 % confidence interval 1.18-24, p = 0.030)]. In a model including the strongest clinical and echocardiographic predictors of the primary outcome, abnormal GLS demonstrated significant incremental benefit for risk stratification [net reclassification improvement 0.75 (95 % confidence interval 0.21-1.23, p < 0.0001)]. Abnormal GLS is an independent predictor of adverse outcomes in HCM patients. Standardized use of GLS may provide significant incremental value over traditional variables for risk stratification.

Doppler-derived left ventricular end-diastolic pressure prediction model using the combined analysis of mitral and pulmonary A waves in patients with coronary artery disease and preserved left ventricular systolic function.

The aim of this study was to analyze the components of mitral and pulmonary A waves and to construct a Doppler-derived left ventricular (LV) end-diastolic pressure (EDP) prediction model based on the combined analysis of transmitral and pulmonary venous flow velocity curves. Combined analysis of transmitral and pulmonary venous flow velocity curves at atrial contraction is a reliable predictor of increased LV filling pressure. The duration of pulmonary and mitral A waves is determined by the sum of respective acceleration and deceleration time. Mitral flow and left upper pulmonary vein flow velocity curves were recorded simultaneously with LVEDP in 40 consecutive patients (aged 59 +/- 8 years) with coronary artery disease and preserved LV systolic function. Differences in all parameters represent values of pulmonary minus those of mitral A wave curve. The difference in deceleration time was the strongest candidate, being included in all models. After redundancy evaluation, we reached the following model: LVEDP = 20.61 + 0.229 x difference in deceleration time (r(2) = 0.80, p <0.001). In the entire study group, the difference in duration and in deceleration time of the A wave was highly correlated with LVEDP (r = 0.79, p <0.001, and r = 0.88, p <0.001, respectively). The entire study group was further divided according to whether LVEDP was above (group I, 20 patients) or below (group II, 20 patients) the median value (15.5 mm Hg). In group I, the difference in duration and in deceleration time correlated well (r = 0.62, p = 0.01, and r = 0.75, p = 0.001, respectively) with LVEDP, whereas in group II only the difference in deceleration time correlated well (r = 0.68, p = 0.005). In patients with coronary artery disease and preserved LV systolic function, the combined analysis of mitral and pulmonary A waves can predict LVEDP. The difference in deceleration time between pulmonary and mitral A waves can reliably evaluate high and normal LVEDP.

Comparison of cardiac output measured with echocardiographic volumes and aortic Doppler methods during mechanical ventilation.

OBJECTIVE: To compare two transesophageal echocardiographic methods of cardiac output and stroke volume measurement in mechanically ventilated patients. DESIGN: Prospective clinical study. SETTING: Operating room (group I) and intensive care unit (group II) in two university hospitals. PATIENTS: Fifteen deeply anesthetized patients undergoing gynecological laparoscopy for sterility (group I) and 40 patients with septic shock (group II). INTERVENTIONS: Transesophageal echocardiography with modification of hemodynamic conditions. MEASUREMENTS AND RESULTS: Left ventricular (LV) volumes, cardiac (CI) and stroke index (SI) were measured with two methods using either LV volumes or aortic Doppler. These values were significantly lower in group I compared to group II. Using ANOVA and paired t-tests, there were no significant differences between the two methods of measurement. Correlation between these methods was better in group II than in group I, although not significantly so. In group I, bias for CI measurements was low (0.05 l/min per m(2)), with a weak agreement in terms of the 95% confidence interval (-1.17; 1.06 l/min per m(2)) compared to the mean values obtained with both methods (1.3 l/min per m(2)). In group II, bias for CI measurements was lower (0.2 l/min per m(2)). Agreement was weak, regarding 95% confidence intervals (-1.7; 1.3 l/min per m(2)) compared to the mean values (3 l/min per m(2) with the LV volumes method and 3.2 l/min per m(2) and with the Doppler method). CONCLUSIONS: Cardiac output and stroke volume can be measured from LV volumes in mechanically ventilated patients, yielding relevant information. However, the accuracy of LV volume measurements is not excellent compared to the aortic Doppler method. Thus, this latter technique should still be considered as the gold standard.

Assessment of global left ventricular function in normal children and in children with dilated cardiomyopathy.

A Doppler index combining systolic and diastolic time intervals (Tei index) has been reported to be useful for assessing global left ventricular (LV) function and predicting clinical outcome in adult patients with LV dysfunction. However, normal values in children and age-related changes in the index have not yet been clarified. The aim of this study was to prospectively determine normal values of the Tei index and the effect of aging on the index in children and to assess the global cardiac function in patients with dilated cardiomyopathy with this index. The subjects included 161 consecutive normal children aged 30 days to 18 years and 5 patients with dilated cardiomyopathy. The Tei index was defined as the sum of the isovolumetric contraction time and the isovolumetric relaxation time divided by the ejection time and was measured from conventional LV outflow and inflow Doppler velocity profiles. The Tei index correlated significantly with the logarithm of age (r = 0.51, P <. 001). The index decreased with aging until 3 years and then did not change after age 3 years. The Tei index in children under age 3 years (0.40 +/- 0.09, n = 80) was significantly higher than that in children ranging in age from 3 to 18 years old (0.33 +/- 0.02, n = 81). The index in patients with dilated cardiomyopathy (0.78 +/- 0. 28) was markedly increased compared with that in normal subjects. Age-related changes in the Tei index may reflect maturational or developmental alterations in the LV properties in infants. The data in this study give basic information for further quantitative assessment of global cardiac function in children with congenital or acquired heart disease.

Tissue Doppler, a fundamental tool for parametric imaging.

Tissue Doppler has been used for clinical applications since 1989. It has been developed from a pulsed Doppler acquisition tool towards a method where extraction of velocities can be performed from colour-coded images. This has introduced a further development into different forms of parametric images describing different myocardial functions as colour-coded information, like deformation imaging, motion imaging and phase imaging. The technical requirements have been established with temporal requirements of frame rates in acquisition exceeding 100 frames s(-1). The most powerful application of the tissue Doppler technique today is perhaps to quantify the myocardial functional reserve, during stress echocardiography, making the method applicable to diagnose the presence of coronary disease with an accuracy exceeding that of nuclear and other non-invasive techniques. The method has also great potential for future developments with introduction of more regional measuring variables.

[Evaluation of early alterations in transmitral diastolic flow and tissue Doppler findings of the Basal segments of both ventricles in early period after coronary angioplasty]. / Koroner anjiyoplasti sonrasi erken dönemde mitral diyastolik akim ve her iki ventrikül bazal bölge doku Doppler bulgularindaki degisikliklerin degerlendirilmesi.

OBJECTIVE: Diastolic dysfunction of the left ventricle (LV) appears to be the earliest manifestation of myocardial ischemia. Experimental and clinical studies have shown that both early and late improvements of diastolic function occur after percutaneous transluminal coronary angioplasty (PTCA). Because of the limited utility of transmitral flow profile in the evaluation of the LV diastolic function, recently, assessment of myocardial velocities by Doppler tissue imaging is gaining importance. The aim of this study was to determine the utility of pulsed wave tissue Doppler (PWTD) pattern from the mitral and tricuspid annulus motion in the evaluation of early alterations of the LV diastolic function after revascularization with PTCA in patients with coronary artery disease. METHODS: Pulsed wave tissue Doppler in combination with conventional pulsed-Doppler indices were used to evaluate LV diastolic function before and 24 hours after PTCA. Examinations were performed on 31 patients with chronic ischemic heart disease underwent elective first PTCA. As conventional Doppler indices, early diastolic mitral velocity (e), and its deceleration time (Edt), isovolumic relaxation time (IVRT), late diastolic mitral velocity (a) were measured. Using 2-dimensional echocardiography four chamber apical window, mitral annulus septal and lateral site and tricuspid annulus lateral site were viewed, and PWTD velocity profile were used to calculate; early diastolic maximum velocity and time, late diastolic maximum velocity and time, systolic maximum velocity and time, IVRT and isovolumic contraction time (IVCT) from each site. RESULTS: After PTCA only 2 transmitral conventional pulsed-Doppler indices were changed significantly (IVRT; from 139.7+/-22.2 msec to 120.0+/-15.9 msec, p=0.0001; Edt; from 279+/-11 msec to 248+/-36 msec, p=0.005). However, PWTD (mitral annulus lateral site) analyses showed significant improvement in most of the diastolic parameters: e/a ratio - from 0.80+/-0.26 to 0.89+/-0.22, p=0.012; s wave - from 11.6+/-3.1 cm/sec to 13.2+/-3.6 cm/sec, p=0.03; IVRT - from 130+/-37 msec to 108+/-29 msec, p=0,0001; IVCT - from 84.1+/-19.2 msec to 75.6+/-12.2 msec, p=0.02. Similar significant changes were also observed in the PWTD diastolic parameters of both the mitral annulus septal and tricuspid annulus sites. Peak systolic velocities that reflect the LV systolic functions, of three annular sites significantly improved early after PTCA, however ejection fraction was not changed as much as tissue Doppler parameters (s maximum velocity before PTCA: 11.7+/-3.1 cm/sec versus 13.2+/-3.6 cm/sec after PTCA, p=0.03). CONCLUSION: Tissue Doppler indices of the mitral annulus reflecting both the diastolic and systolic functions, improve early after successful PTCA in patients with coronary artery disease.