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.

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.

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.

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.

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.

Guidance for accurate and consistent tissue Doppler velocity measurement: comparison of echocardiographic methods using a simple vendor-independent method for local validation.

BACKGROUND: Variability has been described between different echo machines and different modalities when measuring tissue velocities. We assessed the consistency of tissue velocity measurements across different modalities and different manufacturers in an in vitro model and in patients. Furthermore, we present freely available software tools to repeat these evaluations. METHODS AND RESULTS: We constructed a simple setup to generate reproducible motion and used it to compare velocities measured using three echocardiographic modalities: M-mode, speckle tracking, and tissue Doppler, with a straightforward, non-ultrasound, optical gold standard. In the clinical phase, 25 patients underwent M-mode, speckle tracking, and tissue Doppler measurements of s', e', and a' velocities. In vitro, the M-mode and speckle tracking velocities agreed with optical assessment. Of the three possible tissue Doppler measurement conventions (outer, middle, and inner edge) only the middle agreed with optical assessment (discrepancy -0.20 (95% CI -0.44 to 0.03) cm/s, P = 0.11, outer +5.19 (4.65 to 5.73) cm/s, P < 0.0001, inner -6.26 (-6.87 to -5.65) cm/s, P < 0.0001). A similar pattern occurred across all four studied manufacturers. M-mode was therefore chosen as the in vivo gold standard. Clinical measurements of s' velocities by speckle tracking and the middle line of the tissue Doppler showed concordance with M-mode, while the outer line overestimated significantly (+1.27(0.96 to 1.59) cm/s, P < 0.0001) and the inner line underestimated (-1.82 (-2.11 to -1.52) cm/s, P < 0.0001). CONCLUSIONS: Echocardiographic velocity measurements can be more consistent than previously suspected. The statistically modal velocity, found at the centre of the spectral pulsed wave tissue Doppler envelope, most closely represents true tissue velocity. This article includes downloadable, vendor-independent software enabling calibration of echocardiographic machines using a simple, inexpensive in vitro setup.

Echocardiographic assessment of coronary artery flow in normal canines and model dogs with myocardial infarction.

This study was conducted to evaluate the usefulness of coronary arterial profiles from normal dogs (11 animals) and canines (six dogs) with experimental myocardial infarction (MI) induced by ligation of the left coronary artery (LCA). Blood velocity of the LCA and right coronary artery (RCA) were evaluated following transthoracic pulsed-wave Doppler echocardiography. The LCA was observed as an infundibular shape, located adjacent to the sinus of Valsalva. The RCA appeared as a tubular structure located 12 o'clock relative to the aorta. In normal dogs, the LCA and RCA mean peak diastolic velocities were 20.84 ± 3.24 and 19.47 ± 2.67 cm/sec, respectively. The LCA and RCA mean diastolic deceleration times were 0.91 ± 0.14 sec and 1.13 ± 0.20 sec, respectively. In dogs with MI, the LCA had significantly (p < 0.01) lower peak velocities (14.82 ± 1.61 cm/sec) than the RCA (31.61 ± 2.34 cm/sec). The RCA had a significantly (p < 0.01) rapid diastolic deceleration time (0.71 ± 0.06 sec) than that found in the LCA (1.02 ± 0.22 sec) of MI dogs. In conclusion, these profiles may serve as a differential factor for evaluating cardiomyopathy in dogs.

Echocardiographic assessment of coronary artery flow in normal canines and model dogs with myocardial infarction

This study was conducted to evaluate the usefulness of coronary arterial profiles from normal dogs (11 animals) and canines (six dogs) with experimental myocardial infarction (MI) induced by ligation of the left coronary artery (LCA). Blood velocity of the LCA and right coronary artery (RCA) were evaluated following transthoracic pulsed-wave Doppler echocardiography. The LCA was observed as an infundibular shape, located adjacent to the sinus of Valsalva. The RCA appeared as a tubular structure located 12 o'clock relative to the aorta. In normal dogs, the LCA and RCA mean peak diastolic velocities were 20.84 +/- 3.24 and 19.47 +/- 2.67 cm/sec, respectively. The LCA and RCA mean diastolic deceleration times were 0.91 +/- 0.14 sec and 1.13 +/- 0.20 sec, respectively. In dogs with MI, the LCA had significantly (p < 0.01) lower peak velocities (14.82 +/- 1.61 cm/sec) than the RCA (31.61 +/- 2.34 cm/sec). The RCA had a significantly (p < 0.01) rapid diastolic deceleration time (0.71 +/- 0.06 sec) than that found in the LCA (1.02 +/- 0.22 sec) of MI dogs. In conclusion, these profiles may serve as a differential factor for evaluating cardiomyopathy in dogs.

Age- and sex-based reference limits and clinical correlates of myocardial strain and synchrony: the Framingham Heart Study.

BACKGROUND: There is rapidly growing interest in applying measures of myocardial strain and synchrony in clinical investigations and in practice; data are limited regarding their reference ranges in healthy individuals. METHODS AND RESULTS: We performed speckle-tracking-based echocardiographic measures of left ventricular myocardial strain and synchrony in healthy adults (n=739, mean age 63 years, 64% women) without cardiovascular disease. Reference values were estimated using quantile regression. Age- and sex-based upper (97.5th quantile) limits were: -14.4% to -17.1% (women) and -14.4 to -15.2% (men) for longitudinal strain; -22.3% to -24.7% (women) and -17.9% to -23.7% (men) for circumferential strain; 121 to 165 ms (women) and 143 to 230 ms (men) for longitudinal segmental synchrony (SD of regional time-to-peak strains); and 200 to 222 ms (women) and 216 to 303 ms (men) for transverse segmental synchrony. In multivariable analyses, women had ≈1.7% greater longitudinal strain, ≈2.2% greater transverse strain, and ≈3.2% greater circumferential strain (P<0.0001 for all) compared with men. Older age and higher diastolic blood pressure, even within the normal range, were associated with worse transverse segmental synchrony (P<0.001). Overall, covariates contributed to ≤12% of the variation in myocardial strain or synchrony in this healthy sample. CONCLUSIONS: We estimated age- and sex-specific reference limits for measures of left ventricular strain and synchrony in a healthy community-based sample, wherein clinical covariates contributed to only a modest proportion of the variation. These data may facilitate the interpretation of left ventricular strain-based measures obtained in future clinical research and practice.

Noninvasive LV pressure estimation using subharmonic emissions from microbubbles.

To develop a new noninvasive approach to quantify left ventricular (LV) pressures using subharmonic emissions from microbubbles, an ultrasound scanner was used in pulse inversion grayscale mode; unprocessed radiofrequency data were obtained with pulsed wave Doppler from the aorta and/or LV during Sonazoid infusion. Subharmonic data (in dB) were extracted and processed. Calibration factor (mm Hg/dB) from the aortic pressure was used to estimate LV pressures. Errors ranged from 0.19 to 2.50 mm Hg when estimating pressures using the aortic calibration factor, and were higher (0.64 to 8.98 mm Hg) using a mean aortic calibration factor. Subharmonic emissions from ultrasound contrast agents have the potential to noninvasively monitor LV pressures.

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.

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.

Improvement in the assessment of diastolic function in a clinical echocardiography laboratory following implementation of a quality improvement initiative.

BACKGROUND: The aim of this study was to demonstrate improvement in the characterization of diastolic function in the routine practice of a clinical echocardiography laboratory after the implementation of a quality improvement initiative. The echocardiographic analysis of left ventricular (LV) diastolic dysfunction is an inherently complex process involving the integration of multiple indices for accurate assessment. METHODS: A baseline survey of 50 randomly chosen echocardiographic studies was reviewed for the accuracy of diastolic function assessment. A four-step quality improvement protocol was then initiated: (1) sonographer and physician education; (2) the implementation of data acquisition protocol changes using LV inflow, tissue Doppler velocity of the mitral annulus in early diastole (e'), flow propagation velocity of LV inflow (Vp), and left atrial volume index (LAVI), along with the establishment of uniform criteria for diagnostic interpretation; (3) peer review of performance; and (4) focused interactive case review sessions. RESULTS: At baseline, measurements of LV inflow were most often correct (100% accurate), while measurements of e' (82% accurate), Vp (12% accurate), and LAVI (12% accurate) and the proper classification of diastolic function (44% accurate) were significantly limited. After the quality improvement initiative, there were significant increases in the accuracy of all recorded measurements, with e' 92% accurate (a 10% improvement; P < .10), Vp 67% accurate (a 55% improvement; P < .001), LAVI 80% accurate (a 68% improvement, P < .001), and proper characterization of diastolic function 76% accurate (a 32% improvement, P < .001). CONCLUSIONS: A multifaceted quality improvement protocol including staff education, systematic support with enhanced infrastructure, and peer review with feedback can be effective for improving the clinical performance of a nonacademic echocardiography laboratory in the characterization of diastolic function.

Effect of recommendations on interobserver consistency of diastolic function evaluation.

OBJECTIVES: We sought the impact of recent recommendations on observer concordance on interpretation of diastolic stage and assessment of filling pressure. BACKGROUND: Worsening stages of diastolic dysfunction are associated with worsening outcome. However, the echocardiographic classification of diastolic function is complex, and parameters may be discordant. The interobserver agreement of diastolic assessment is undefined. METHODS: A complete diastolic evaluation (transmitral flow, left atrial volume, tissue Doppler, pulmonary venous flow, mitral flow propagation, and left ventricular images) was obtained in 20 patients and interpreted by 14 experts in 8 countries (280 case reads). Each investigator was asked to interpret diastolic class and left ventricular filling pressure. Brain natriuretic peptide level was drawn on the same day of the echocardiogram to corroborate filling pressures obtained by the echocardiogram. Concordance was assessed as kappa, and accuracy was compared with specific application of the recommendations by 2 investigators. RESULTS: For recognition of raised filling pressure, the sensitivity and specificity of readers for raised filling pressure defined by the reference read were 66 ± 37% and 88 ± 26%, respectively. Complete agreement among all readers was obtained in 10 of 20 cases. Diagnosis of normal and categories of abnormal filling was correct in 71% to 95%, with the lowest values obtained for normal and pseudonormal filling. There was no difference between U.S. and international readers. Not all patients in each diastolic stage showed all of the changes that are typical of that stage, and variations appeared to be attributable to differences in weighting of conflicting observations. Overall, kappa values for filling pressure and diastolic class were 0.71 (range 0.60 to 0.80) and 0.68 (range 0.54 to 0.86). CONCLUSIONS: Correct results for estimation of filling pressure were obtained by a high proportion of readers. Classification of diastolic stages continues to be variable and might be addressed by provision of a uniform hierarchy of observations.