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Background: The aim of this study was to estimate geometric errors made by the two-dimensional (2D) transthoracic echocardiographic (TTE) pulsed-wave Doppler flow (PWDF) method in calculating regurgitant volume (RVol) and effective regurgitant orifice area (EROA) in degenerative mitral regurgitation (MR) by comparison with the three-dimensional (3D) transesophageal echocardiographic (TEE) PWDF method., Methods: RVol and EROA were calculated in 22 patients with degenerative MR using the conventional 2D TTE PWDF method on the basis of monoplanar dimensions and a circular geometric assumption of the cross-sectional areas (CSAs) of the mitral annulus (MA) and the left ventricular outflow tract (LVOT) and the 3D TEE PWDF method, in which the CSAs of the MA and LVOT were measured directly in "en face" views. Diameters of the MA and LVOT were also measured in similar views as with TTE imaging in 3D TEE data sets., Results: Both the MA and LVOT were oval. Mean MA diameters were 41 ± 4 mm (3D TEE major axis), 31 ± 4 mm (3D TEE minor axis), 39 ± 5 mm (2D TTE imaging), and 38 ± 5 mm (2D TEE imaging). Mean LVOT diameters were 29 ± 4 mm (3D TEE major axis), 21 ± 2 mm (3D TEE minor axis), 22 ± 2 mm (2D TTE imaging), and 23 ± 2 mm (2D TEE imaging). Compared with 3D TEE measurements, mitral annular CSA was overestimated by 13 ± 12% on 2D TTE imaging and by 7 ± 14% on 2D TEE imaging, while LVOT CSA was underestimated by 23 ± 10% and 17 ± 10%, respectively. Mean values of RVol were 95 ± 43 mL (3D TEE PWDF), 137 ± 56 mL (2D TTE PWDF), 120 ± 45 mL (2D TEE PWDF), and 111 ± 49 mL (flow convergence). Mean EROAs were 69 ± 34 mm2 (3D TEE PWDF), 98 ± 45 mm2 (2D TTE PWDF), 88 ± 42 mm2 (2D TEE PWDF), and 79 ± 36 mm2 (flow convergence). Observer variability for 3D TEE imaging was better than for 2D imaging., Conclusions: The 2D TTE PWDF method overestimates mitral RVol and EROA significantly because monoplanar 2D measurements represent mitral annular major-axis diameter and LVOT minor-axis diameter, and assumed circular CSAs of the MA and LVOT are oval., (Copyright © 2013 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.)

Background: The diagnosis of noncompaction cardiomyopathy (NCCM) remains subject to controversy. Because NCCM is probably caused by an intrauterine arrest of the myocardial fiber compaction during embryogenesis, it may be anticipated that the myocardial fiber helices, normally causing left ventricular (LV) twist, will also not develop properly. The resultant LV rigid body rotation (RBR) may strengthen the diagnosis of NCCM. The purpose of the current study was to explore the diagnostic value of RBR in a large group of patients with prominent trabeculations., Methods: The study comprised 15 patients with dilated cardiomyopathy, 52 healthy subjects, and 52 patients with prominent trabeculations, of whom a clinical expert in NCCM defined 34 as having NCCM. LV rotation patterns were determined by speckle-tracking echocardiography and defined as follows: pattern 1A, completely normal rotation (initial counterclockwise basal and clockwise apical rotation, followed by end-systolic clockwise basal and counterclockwise apical rotation); pattern 1B, partly normal rotation (normal end-systolic rotation but absence of initial rotation in the other direction); and pattern 2, RBR (rotation at the basal and apical level predominantly in the same direction)., Results: The majority of normal subjects had LV rotation pattern 1A (98%), whereas the 18 subjects with hypertrabeculation not fulfilling diagnostic criteria for NCCM predominantly had pattern 1B (71%), and the 34 patients with NCCM predominantly had pattern 2 (88%). None of the patients with dilated cardiomyopathy showed RBR. Sensitivity and specificity of RBR for differentiating NCCM from "hypertrabeculation" were 88% and 78%, respectively., Conclusions: RBR is an objective, quantitative, and reproducible functional criterion with good predictive value for the diagnosis of NCCM as determined by expert opinion., (Copyright © 2011 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.)

Background: Almost all patients with hypertrophic cardiomyopathy (HCM) have some degree of left ventricular (LV) diastolic dysfunction. Nevertheless, the pathophysiology remains incompletely characterized. Conceptually, an ideal therapeutic agent should target the underlying mechanisms that cause LV diastolic dysfunction. Assessment of diastolic LV untwisting could potentially be helpful to gain insight into the mechanism of diastolic dysfunction. The purpose of this study was to investigate LV untwisting in patients with HCM and control subjects., Methods: LV untwisting parameters were assessed using speckle-tracking echocardiography in 75 consecutive patients with HCM and compared with those from 75 healthy control subjects., Results: Untwisting at 5%, 10%, and 15% of diastole was lower in patients with HCM (all P values < .001) compared with control subjects. Peak diastolic untwisting velocity (-92 +/- 32 degrees/s vs -104 +/- 39 degrees/s, P < .05) and untwisting rate from peak systolic twist to mitral valve opening (MVO) (-37 +/- 20 degrees/s vs -46 +/- 22 degrees/s, P < .01) were lower, while the for diastolic duration normalized time-to-peak diastolic untwisting velocity (17 +/- 9% vs 13 +/- 9%, P < .05) was higher in patients with HCM. Untwisting rate from peak systolic twist to MVO was negatively correlated with the E/A ratio (R(2) = 0.15, P < .01). Peak diastolic untwisting velocity and untwisting rate from peak systolic twist to MVO were increased in mild but decreased in moderate and severe diastolic dysfunction compared with control subjects., Conclusion: LV untwisting is delayed in HCM, which probably significantly contributes to diastolic dysfunction.

Background: Mitral annular velocity may be measured angle independently by speckle tracking echocardiography (STE), in contrast with tissue Doppler imaging (TDI). The purpose of the current study was to compare STE and TDI, with respect to 1) the accuracy of velocity measurements in a moving phantom, 2) the feasibility and reproducibility of measurement of mitral annular velocities in a clinical setting, and 3) the estimation of left ventricular filling pressures using mitral annular velocities., Methods: The velocity of a moving phantom, using different angles of insonation, and mitral annular velocities of 80 nonselected patients and 50 healthy volunteers were determined using TDI and STE. A subgroup of 20 patients was studied during right-sided heart catheterization., Results: When the motion direction of the phantom was parallel to the ultrasound beam, both TDI and STE determined velocities accurately. With increasing angle of insonation, TDI-derived velocity decreased, whereas STE-derived velocity remained unchanged. The feasibility of mitral annular velocities measured by TDI and STE was comparable (98% vs 95%, P = not significant). Although for both techniques correlations between measured mitral annular velocities at repeated examinations were good, the test-retest variability of mitral annular velocities by TDI was higher. E/Em ratio by STE correlated better to pulmonary capillary wedge pressure (R(2) = 0.51, P < .001) compared with E/Em ratio derived from TDI (R(2) = 0.35, P < .01), although the difference in correlation was not statistically significant because of the limited sample size., Conclusion: Tissue velocities can be accurately determined by STE in a moving phantom and are angle independent, in contrast with TDI measurements. Furthermore, STE is a feasible and better reproducible method for the assessment of mitral annular velocities in a clinical setting.

Objective: To assess real-time 3-dimensional echocardiography (RT3DE)-derived left ventricular (LV) systolic dyssynchrony parameters: (1) normal values, (2) characteristics in patients with heart failure (HF) and a wide or narrow QRS complex, (3) interobserver and intraobserver variability with current state of the art RT3DE hardware and software technology, and (4) incremental value in patients with HF who receive cardiac resynchronization therapy (CRT)., Methods: The study involved 84 patients with HF (mean age 54 +/- 15 years, 50 men) and 60 healthy volunteers (mean age 41 +/- 15 years, 36 men). Semiautomated LV endocardial border tracking was used to calculate regional time-to-minimum systolic volume and to generate parametric maps and the systolic dyssynchrony index (SDI), defined as the standard deviation of time-to-minimum systolic volume of the 16 LV segments expressed in percentage of R-R duration., Results: The volume rate of the RT3DE datasets in patients with HF was 31 +/- 9 Hz (range 15-42 Hz). The normal value of the SDI was 4.1% +/- 2.2% (range <1.0%-8.9%). Patients with HF had a larger SDI (13.4% +/- 8.1%, P < .001). There was only a weak correlation (r2 = 0.07, P < .05) between the QRS duration and the SDI. Interobserver interclass correlation and variability of the SDI depended on image quality (good: 0.993 and 9%, moderate: 0.907 and 16%, respectively). Interobserver agreement for the identification of the most delayed LV segment depended on image quality (good: 90%, moderate: 76%). Thirty-nine patients underwent CRT. At the 12-month follow-up, LV volumetric responders had a significant reduction in the SDI (16.3% +/- 3.3% to 7.7% +/- 2.4%, P < .001)., Conclusion: With state of the art technology, RT3DE allows reproducible assessment of LV systolic dyssynchrony, which may be useful to identify potential responders to CRT.

Background: Speckle tracking echocardiography is increasingly used to quantify left ventricular (LV) twist. However, one of the limitations of the assessment of LV twist by speckle tracking echocardiography is the crucial dependence on correct acquisition of a LV apical short-axis. This study sought to assess the influence of transducer position on LV apical rotation measurements., Methods: The study population consisted of 58 consecutive healthy volunteers (mean age 38 +/- 13 years, 25 men). To obtain parasternal short-axis images at the LV apical level, the following protocol was used. From the standard parasternal position (LV and aorta most inline, with the mitral valve tips in the middle of the sector) an as-circular-as-possible short-axis image of the LV apex, just proximal to the level with end-systolic LV luminal obliteration, was obtained by angulation of the transducer (position 1). From this position, the position of the transducer was changed to one (position 2) and two (position 3) intercostal spaces more caudal with subsequent similar transducer adaptations., Results: In 8 volunteers (14%) parasternal image quality was insufficient for speckle tracking echocardiography. In 13 volunteers (22%) the LV apical short-axis could only be obtained from one transducer position. In the remaining volunteers with two (n = 27) or three (n = 10) available transducer positions, a more caudal transducer position was associated with increased measured LV apical rotation. Mean measured LV apical rotation was 5.2 +/- 1.8 degrees at position 1, 7.3 +/- 2.6 degrees at position 2 (P < .001), and 8.7 +/- 2.2 degrees at position 3 (P < .001 vs position 1 and P < .05 vs position 2)., Conclusion: A more caudal transducer position is associated with increased measured LV apical rotation.

Objective: We evaluated two different commercially available real-time 3-dimensional echocardiographic semiautomated border detection algorithms for left ventricular (LV) volume analysis in patients with cardiomyopathy and distorted LV geometry., Methods: A total of 53 patients in sinus rhythm with various types of cardiomyopathy (mean age 56 +/- 11 years, 28 men) and adequate 2-dimensional image quality were included. The real-time 3-dimensional echocardiographic multiplane interpolation (MI) and full volume reconstruction (FVR) methods were used for LV volume analysis. Magnetic resonance imaging was used as the reference method., Results: A strong correlation (R(2) > 0.95) was found for all LV volume and ejection fraction measurements by either real-time 3-dimensional echocardiographic method. Analysis time was shorter with the FVR method (6 +/- 2 vs 15 +/- 4 minutes, P < .01) as compared with the MI method. Bland-Altman analysis showed greater underestimation of end-diastolic and end-systolic volumes by MI compared with FVR. For the MI method a bias of -24.0 mL (-15.0% of the mean) for end-diastolic volume and -11.3 mL (-18.0% of the mean) for end-systolic volume was found. For FVR analysis these values were -9.9 mL (-6.0% of the mean) and -5.0 mL (-9.0% of the mean), respectively. Ejection fraction was similar for the MI and FVR method with a mean difference compared with magnetic resonance imaging of 0.6 (1.0%) and 0.8 (1.3%), respectively., Conclusion: In patients with cardiomyopathy, distorted LV geometry, and good 2-dimensional image quality, the FVR method is faster and more accurate than the MI method in assessment of LV volumes.

The study included 30 patients with hypertrophic cardiomyopathy (HCM) (obstructive and nonobstructive) and 15 control subjects. End-diastolic mitral annulus area (MAA(3D)) and mitral valve area (MVA(3D)) were measured by real-time 3-dimensional (3D) echocardiography. MVA(2D) and peak mitral inflow A wave velocity (V) were measured by 2-dimensional (2D) echocardiography. Left atrial ejection force (LA-EF) was calculated by 2D echocardiography and real-time 3D echocardiography using the formula: 0.5 x 1.06 x (MAA or MVA) x V2, where (1.06) is blood viscosity. LA-EF(2D-MVA), LA-EF(3D-MVA), LA-EF(3D-MAA), and V were significantly higher in patients with HCM than control subjects (P < .001). LA-EF(2D-MVA) and LA-EF(3D-MVA) were lower than LA-EF(3D-MAA) in HCM only (P < .001). In obstructive HCM, LA-EF(2D-MVA), LA-EF(3D-MVA), LA-EF(3D-MAA), and V were significantly higher than in nonobstructive HCM (P < .05). Left ventricular outflow tract gradient contributed independently to high LA-EF in obstructive HCM. We concluded that HCM is associated with higher LA-EF than normal, and higher in obstructive HCM than nonobstructive indicating a higher atrial workload that is reflected by LA-EF(3D-MAA).