Three-dimensional Transthoracic Echocardiography Research Articles

Prognostic value of three-dimensional echocardiographic right ventricular ejection fraction in patients with pulmonary arterial hypertension.

BackgroundRight ventricular (RV) function is an independent predictor of clinical outcomes in patients with pulmonary arterial hypertension (PAH). However, it remains controversial which RV parameter should be measured as an appropriate index for the treatment of PAH. The aim of this study was to identify the most useful parameter that correlates with hemodynamics and predicts clinical outcomes in PAH.ResultsMost of the clinical and echocardiographic RV parameters were significantly correlated with pulmonary vascular resistance (PVR) as well as mean pulmonary arterial pressure (mPAP). Among these, three dimensional right ventricular ejection fraction (3DRVEF) showed the strongest hemodynamic correlation, followed by 6-minute walk distance. Receiver operating characteristic analysis of association with cardiac events including death, hospitalization, and intervention revealed a greater area under the curve for 3DRVEF than for mPAP (0.78 vs. 0.74). Kaplan-Meier analysis showed that patients with 3DRVEF less than 38% had significantly shorter event-free survival than those with greater than 38% (P = 0.0007). Finally, the Cox proportional hazards analysis revealed that 3DRVEF, but not mPAP, was an independent predictor of clinical events in PAH.Materials and MethodsEighty-six consecutive patients were enrolled in this study. RV hemodynamic parameters were measured by right heart catheterization (RHC). RV function was assessed using two-dimensional speckle-tracking echocardiography and three-dimensional transthoracic echocardiography (3DTTE) to evaluate RV free wall global strain (RVFS) and RVEF.ConclusionsRVEF measured by 3DTTE could be a useful parameter for noninvasively assessing RV hemodynamics and predicting the clinical outcomes in PAH patients.

Clinical utility of three-dimensional echocardiography in the evaluation of tricuspid regurgitation induced by implantable device leads.

Implantable device leads could cause tricuspid regurgitation (TR) by interfering with leaflet motion. This study evaluated the feasibility of using three-dimensional transthoracic echocardiography (3DTTE) to identify lead-induced tricuspid regurgitation (LITR). 3DTTE full-volume images of the right ventricle (RV) and zoomed images of the tricuspid valve were obtained in 207 patients with implanted devices, and the images were analyzed. TR severity was estimated based on measurements of the proximal isovelocity surface area (PISA) radius. 3DTTE clearly identified the course and position of the leads in 74% of the patients. The lead tips were located in the RV apex or outflow tract in 95% of patients and in the interventricular septum (IVS) in 5% of patients. At the tricuspid annular level, 25% of leads were impinging on a leaflet, 41% were located in the commissure of two leaflets, and 34% were in the middle of the tricuspid orifice. 3D images revealed that when the lead tip was in the IVS or the lead was impinging on a leaflet, the device lead was more likely to interfere with leaflet mobility (P<.05). Interfering leads were associated with more significant TR than noninterfering leads (P<.05). 3DTTE showed a clear association between lead interference and TR worsening after lead placement. 3DTTE guidance should be considered for the placement of leads.

Three-Dimensional Echocardiographic Assessment of Left Heart Chamber Size and Function with Fully Automated Quantification Software in Patients with Atrial Fibrillation

Echocardiographic determination of left heart chamber volumetric parameters by using manual tracings during multiple beats is tedious in atrial fibrillation (AF). The aim of this study was to determine the usefulness of fully automated left chamber quantification software with single-beat three-dimensional transthoracic echocardiographic data sets in patients with AF. Single-beat full-volume three-dimensional transthoracic echocardiographic data sets were prospectively acquired during consecutive multiple cardiac beats (≥10 beats) in 88 patients with AF. In protocol 1, left ventricular volumes, left ventricular ejection fraction, and maximal left atrial volume were validated using automated quantification against the manual tracing method in identical beats in 10 patients. In protocol 2, automated quantification-derived averaged values from multiple beats were compared with the corresponding values obtained from the indexed beat in all patients. Excellent correlations of left chamber parameters between automated quantification and the manual method were observed (r=0.88-0.98) in protocol 1. The time required for the analysis with the automated quantification method (5min) was significantly less compared with the manual method (27min) (P<.0001). In protocol 2, there were excellent linear correlations between the averaged left chamber parameters and the corresponding values obtained from the indexed beat (r=0.94-0.99), and test-retest variability of left chamber parameters was low (3.5%-4.8%). Three-dimensional transthoracic echocardiography with fully automated quantification software is a rapid and reliable way to measure averaged values of left heart chamber parameters during multiple consecutive beats. Thus, it is a potential new approach for left chamber quantification in patients with AF in daily routine practice.

Assessment of Ventricular Septal Defect Size and Morphology by Three-Dimensional Transthoracic Echocardiography

Morphologic description of ventricular septal defect (VSD) is mandatory before performing the newly developed transcatheter closure procedure. Inaccurate estimation of defect size has been reported using conventional two-dimensional (2D) transthoracic echocardiography (TTE). The aim of this study was to assess VSD morphology and size using three-dimensional (3D) TTE compared with 2D TTE and surgery. Forty-eight children aged 21.4±29.3months with isolated muscular (n=11 [22.9%]) and membranous (n=37 [77.1%]) VSDs were prospectively included. Three-dimensional images were acquired using full-volume single-beat mode. Minimal diameter, maximal diameter, and systolic and diastolic VSD areas were measured from 3D data sets using multiplanar reconstruction mode (QLAB 9). Maximal-to-minimal VSD diameter ratio was used to assess VSD geometry. Linear regression analysis and the Bland-Altman method were used to compare 3D measurements with 2D and surgical measurements in a subgroup of 15 patients who underwent surgical VSD closure. VSD 3D diameters and areas were measured in all patients (100%; 95% CI, 92.6%-100%). Maximal diameter was lower on 2D TTE compared with 3D TTE (7.3 vs 11.3mm, P<.0001). Mean bias was 4mm, with 95% of values ranging from -1.76 to 9.75mm. Correlation between 3D maximal diameter and surgical diameter was strong (r(2)=0.97, P<.0001), while correlation between maximal 2D diameter and surgical diameter was moderate (r(2)=0.63, P<.0001). VSDs had an oval shape when assessed by 3D TTE. Maximal-to-minimal diameter ratio assessed by 3D TTE was significantly higher in muscular VSDs compared with membranous VSDs (3.20±1.51 vs 2.13±1.28, respectively, P=.01). VSD area variation throughout the cardiac cycle was 32% and was higher in muscular compared with membranous VSDs (49% vs 26%, P=.0001). Three-dimensional TTE allows better VSD morphologic and maximal diameter assessment compared with 2D TTE. VSD shape and its changes during the cardiac cycle can be visually and quantitatively displayed. Three-dimensional echocardiography may thus be particularly useful before and during percutaneous VSD closure.

3D transthoracic echocardiography to assess pulmonary valve morphology and annulus size in patients with Tetralogy of Fallot

Accurate evaluation of the pulmonary valve (PV) is crucial before surgical repair of Tetralogy of Fallot (TOF). To assess PV and pulmonary annulus (PA) morphology using three-dimensional (3D) transthoracic echocardiography (TTE) in infants referred for surgical repair of TOF. Also, to compare PA measurements obtained by 3D TTE with those from other imaging modalities, including two-dimensional (2D) TTE and computed tomography (CT), with reference to surgical measurements. 3D zoom mode was used to assess PV morphology. 2D TTE and CT PA diameters were compared to both vertical and horizontal diameters obtained from 3D datasets. Surgical PA diameters were measured using Hegar's dilators. A total of 29 patients with TOF (median [range] age 6 [3-24] months) were included and all successfully underwent 2D and 3D TTE; 22 also underwent CT. The number of pulmonary leaflets could be visualized in 24 patients (82.8%), with complete concordance with surgical findings. Vertical diameter was significantly longer than horizontal diameter (P<0.001)-underlying PA eccentricity-and was more important in bicuspid than tricuspid valves. Correlations between 2D and 3D TTE diameters were good. Surgical diameter was better correlated with 2D and 3D diameters than with CT diameter. 3D minimum, 2D and CT diameters were significantly lower than surgical diameters, but 3D mean and maximum diameters were not. 3D TTE is accurate to assess PV morphology and PA size in patients with TOF. 2D TTE and CT underestimate PA diameter with reference to surgical diameter, however 3D mean and maximum diameters did not differ significantly.

Assessment of mitral valve morphology using three-dimensional echocardiography. Feasibility and reference values

ObjectivesTo evaluate the feasibility of real time transthoracic three-dimensional echocardiography (RT3DE) for evaluation of normal canine mitral valves (MVs), and to provide reference values for this technique. AnimalsForty-three cardiologically healthy, not sedated dogs. MethodsTransthoracic RT3DE mitral datasets were acquired during two consecutive 6-month periods. The datasets were analyzed using commercially available software. An MV model was drawn using a semiautomated procedure and MV variables were obtained and calculated. The ratio between annulus height and commissural diameter was used as an index of the annulus' saddle-shaped non-planarity. After evaluation of associations between measured variables and body size, the datasets were used to generate reference intervals. Coefficients of variation (CVs), variance components, and repeatability coefficients were calculated for the evaluation of intra-observer, inter-observer, and day-to-day variability. ResultsDatasets could be analyzed in 34 of 43 (79%) dogs. 68 percent of datasets obtained during the first 6-month period could be analyzed and 90% obtained during the second period could be analyzed. An allometric relationship was identified for most MV variables. The MV annulus appeared elliptical and saddle-shaped. Inter- and intra-observer CVs were less than 20%. Coefficient of variation greater than 20% was calculated for the inter-day variation for some variables. Operator and observer were primarily responsible for the variation of most of the variables. ConclusionsEvaluation of canine mitral valves by transthoracic RT3DE is feasible. Canine MVs of healthy dogs analyzed using RT3DE are elliptical and saddle-shaped. Reference intervals for the measured MV variables are proposed.

0443: 3D transthoracic echocardiography assessment of the pulmonary valve in patients with TOF

Accurate evaluation of pulmonary valve (PV) morphology and pulmonary annulus (PA) diameter is crucial before surgical correction of tetralogy of Fallot (TOF). Our aim was to assess PV morphology using three-dimensional transthoracic echocardiography (3D-TTE) in infants with TOF before surgical correction. And to compare PA diameter obtained by different imaging modalities. 30 patients with TOF were prospectively included. All patients underwent 2D and 3D-TTE, 23 patients underwent CT-Scan and 7 cardiac catheterization. PA diameter was measured using 2D-TTE in parasternal short axis view as recommended. 3D dataset was acquired using zoom mode at PV. Both vertical (Dv) and horizontal (Dh) diameters of PA were measured. Mean 3D diameter (3DD) was calculated as (Dv+Dh/2). Eccentricity index (EI) of PA was calculated (Dv—Dh/Dv). These measurements were compared to CT-Scan and angiography when available and to perioperative measurements. Mean age 7.4 months (3-24 months), mean weight 6.6kg (4.5-13.5kg). PV was described as bicuspid in 15/30 patients by 3D-TTE from en face view, with 75% agreement between 3D-TTE and perioperative finding (20/30 patients). PA geometry was slightly asymmetric by 3D-TTE. Dv was significantly larger than Dh (8.4mm vs 7.4mm, p=0.001), and mean EI of PA was (10%). PA was more asymmetric in bicuspid valves rather than in tricuspid valves (EI 14% vs 7%, p=0.002). PA diameter didn’t differ significantly between 2D-TTE, Dh, CT scan and angiography, and were significantly lower than mean 3DD and Dv. There was a very strong correlation between 3DD and perioperative measurement. PA was conserved in 53.3% without significant residual stenosis immediately and after a 20 month of follow-up (except 1 patient requiring balloon dilatation). 3D-TTE in patients with TOF is an accurate method to describe PV, and to measure PA size. Thus could help the surgical repair and the preservation of PV function.

Ebstein’s Anomaly with Gerbode Defect: A Rare Association

Panel A: Two-dimensional and colour flow TTE from Apical four chamber view showing apically displaced STL and sail like ATL with a defect in ventriculoatrial septum (*) with LV to RA flow being simultaneously demonstrated. Panel B: Three-dimensional TTE showing the same defect. Panel C: Two-dimensional TTE from Parasternal long axis view demonstrating the defect (*) with colour flow image confirming the presence of highly turbulent jet from LV to RA. Panel D: Three-dimensional TTE which clearly depicts the defect. Panel E: Continuous Wave Doppler demonstrating a high peak instantaneous gradient of 113 mm Hg across the defect. A 7 year old boy underwent transthoracic echocardiography (TTE) for evaluation of effort intolerance and frequent palpitations with a harsh pansystolic murmur audible all over the precordium. TTE revealed the presence of Ebstein’s anomaly with apically displaced septal tricuspid leaflet (STL) and ‘sail like’ anterior tricuspid leaflet (ATL). There was a direct ventriculoatrial shunt from Left ventricle (LV) to Right atrium (RA) –Gerbode defect with a peak systolic gradient of 113 mm Hg. Ebstein’s anomaly is commonly associated with various other congenital heart defects but association of Ebstein’s with Gerbode defect is very rare (Panel A-E).

Abstract 13135: Association of Three-Dimensional Tricuspid Valve Deformation With Functional Tricuspid Regurgitation

Introduction: Background: Functional tricuspid regurgitation (FTR) is widely recognized as being associated with poor outcomes in patients with various cardiac diseases, and the tricuspid valve (TV) deformation is an important mechanism of FTR. However, the precise assessment of TV deformation by means of two-dimensional echocardiography is limited. Purpose: The purpose of this study was thus to investigate the association of TV deformation with FTR by using three-dimensional transthoracic echocardiography (3D-TTE). Methods: We studied 65 patients with FTR. Their mean age was 60±16 years and 36 patients (55%) were female. FTR was quantified by the ratio of the jet area and corresponding RA area, and more than moderate FTR was defined as significant. 3D-TTE was performed to analyze the tricuspid deformation. Tricuspid tenting height and area were analyzed at the time of maximal systolic closure. TV area index, anterior-posterior (A-P) and septal-lateral (S-L) TV annular diameters were analyzed at end-diastole. Right ventricular longitudinal length, end-diastolic and end-systolic area index (EDAI, ESAI) and right atrial area index (RAA) were also obtained from 3D data set. Results: Twenty-one patients were classified as having significant FTR. Tenting height (6.5±3.1 vs. 4.0±1.8 mm, p&lt;0.001), tenting area (1.3±0.8 vs. 0.7±0.4 cm2, p=0.003), TV area (6.9±1.7 vs. 5.0±1.4 cm2/m2, p&lt;0.001) and S-L (35±4 vs. 28±6 mm, p&lt;0.001) in patients with FTR were significantly larger than those in patients with non-significant FTR, but A-L was not (38±6 vs. 36±7mm). After adjusting for age, ESAI, RAA and tenting height, a multivariate logistic regression analysis showed that TV area (odds ratio 3.1, p=0.04) was independently associated with significant FTR. Conclusions: TV-related parameters were associated with FTR, and TV area was the most important factor for FTR. Our findings by means of 3D-TTE may well have clinical implications for better management of patients with FTR.

Normal Values of Left Ventricular Mass Index Assessed by Transthoracic Three-Dimensional Echocardiography

Pathologic left ventricular (LV) hypertrophy is closely coupled with adverse cardiovascular events. However, normal values of LV mass determined by three-dimensional echocardiography (3DE) have not been established in a large number of healthy subjects over a wide age range. The aims of this study were to (1) validate the accuracy of 3DE for LV mass measurements against cardiac magnetic resonance (CMR), (2) establish the normal range of LV mass index in healthy subjects, and (3) investigate the effects of age, gender, and ethnic diversity on LV mass index. In protocol 1, both transthoracic 3DE and CMR were performed on the same day in 57 patients who underwent clinically indicated CMR examinations. In protocol 2, full-volume data sets were acquired with 3DE in 390 healthy subjects. The LV endocardial and epicardial borders were semiautomatically determined at end-diastole using three-dimensional echocardiographic software. LV mass was calculated as (LV epicardial volume--LV endocardial volume) × 1.05. Excellent correlation was observed between three-dimensional echocardiographic and CMR measurements of LV mass (r = 0.96). Bland-Altman analysis revealed bias of -4.8 g (-3.9% of the mean), with 95% limits of agreement of ± 27.7 g. Normal values of LV mass indexed to body surface area were found to be 70 ± 9 g/m(2) in men and 61 ± 8 g/m(2) in women. Significant age and gender dependence, but no racial dependence, was observed for LV mass index. Three-dimensional echocardiography is an accurate method for measuring LV mass. Age and gender dependence, but no ethnic dependence, of LV mass index was observed in Japanese and American populations. The reported normal reference values of 3DE-determined LV mass index according to age and gender could potentially be useful for diagnosing LV hypertrophy with excellent accuracy.

Echocardiographic Assessment of Mantle Radiation Mitral Stenosis

The long-term sequelae of mantle radiotherapy include lung disease and cardiac disorders. Dyspnea on exertion is a common complaint and can be due to one or more pathologies. We describe a case of mantle radiotherapy-induced mitral stenosis, characterized by aorto-mitral continuity calcification and absent commissural fusion which precludes balloon valvotomy. The latency period is long, and this patient presented 42 years after radiotherapy. Importantly, as previously described with radiation-induced valve disease, significant mitral stenosis developed 10 years after surgery for significant aortic stenosis. Two-dimensional and three-dimensional transthoracic and transesophageal echocardiography should be considered during assessment of symptomatic survivors of Hodgkin's disease where the index of suspicion for valvular stenosis increases over time. Given the natural history of mantle radiation valvular disease, a lower threshold for surgical intervention in radiation-induced mitral stenosis may need to be considered if cardiac surgery is planned for other reasons in order to avoid repeated sternotomy in patients with prior irradiation.

Mitral Annular Dynamics in Mitral Annular Calcification: A Three-Dimensional Imaging Study

The mitral annulus displays complex conformational changes during the cardiac cycle that can now be quantified by three-dimensional echocardiography. Mitral annular calcification (MAC) is increasingly encountered, but its structural and dynamic consequences are largely unexplored. The objective of this study was to describe alterations in mitral annular dimensions and dynamics in patients with MAC. Transthoracic three-dimensional echocardiography was performed in 43 subjects with MAC and 36 age- and sex-matched normal control subjects. Mitral annular dimensions were quantified, using dedicated software, at six time points (three diastolic, three systolic) during the cardiac cycle. In diastole, the calcified annulus was larger and flatter than normal, with increased anteroposterior diameter (29.4 ± 0.6 vs 27.8 ± 0.6 mm, P = .046), reduced height (2.8 ± 0.2 vs 3.6 ± 0.2 mm, P = .006), and decreased saddle shape (8.9 ± 0.6% vs 11.4 ± 0.6%, P = .005). In systole, patients with MAC had greater annular area at all time points (P < .05 for each) compared with control subjects, because of reduced contraction along the anteroposterior diameter (P < .001). Saddle shape increased in early systole (from 10.5% to 13.5%, P = .04) in control subjects but not in those with MAC (P = NS). Valvular alterations were also noted; although mitral valve tent length decreased during systole in both groups, decreases were less in patients with MAC (P < .05 for mid- and late systole). For certain parameters (e.g., annular area), changes were confined largely to those patients with moderate to severe MAC (P = .006 vs control subjects, but nonsignificant for patients with mild MAC). Quantitative three-dimensional echocardiography provides new insights into the dynamic consequences of MAC. This imaging technique demonstrates that the mitral annulus is not made smaller by calcification. However, there is loss of annular contraction, particularly along the anteroposterior diameter, and loss of early systolic folding along the intercommissural diameter. Associated valvular alterations include smaller than usual declines in tenting during systole. These quantitative three-dimensional echocardiographic data provide new insights into the dynamic physiology of the calcified mitral annulus.

Three-Dimensional Transthoracic Echocardiograpic Assessment of Pseudoaneurysm of Mitral Aortic Intervalvular Fibrosa: The Benefit of the Added Dimension

We report a case of 25-year-old female presenting to our department for evaluation of dyspnea on exertion. Two-dimensional transthoracic echocardiography showed a sac-like aneurysmal structure arising from the left ventricular outflow tract region protruding into left atrium. Three-dimensional transthoracic echocardiography clearly delineated the origin of the aneurysm from the region of mitral aortic intervalvular fibrosa, helping in confirmation of the diagnosis.

Successful device closure in a congenital Gerbode defect.

A 22-year-old man was admitted to our department due to mild exertional dyspnea for 2 months. He had no other cardiac symptoms and his medical history was unremarkable. 4/6 systolic murmur was heard at the left sternal border and at the apex. Electrocardiogram revealed sinus rhythm with negative T waves in leads V1 to V4. Two-dimensional transthoracic echocardiography (2D TTE) revealed a clear systolic jet across a defect (7 mm) between the left ventricular outflow tract (LVOT) and right atrium (RA) consistent with a Gerbode type defect located above the tricuspid septal leaflet (Figure 1A). Qp/Qs ratio, maximal velocity (Vmax) and trans-shunt pressure gradient were 2.1, 5.1 m/s and 103 mm Hg, respectively. Right ventricular systolic pressure (RVSP) was estimated at 51 mm Hg assuming a right atrial pressure of 15 mm Hg. The direction of the Doppler signal confirmed our diagnosis (Figure 1B). Furthermore, three-dimensional transthoracic echocardiography (3D TTE) also demonstrated a supravalvular connection between these chambers in detail. Due to the proximity of the defect to the septal tricuspid valve leaflet, the Amplatzer duct occluder (AGA Medical Corporation; Golden Valley, USA) provided a reasonable fit because it has no right-sided disk that might interfere with tricuspid valve motion. The defect size and trans-shunt pressure gradient were compatible with echocardiographic evaluation. The patient refused the surgery; therefore we suggested device closure. After the patient's consent, the defect was successfully closed percutaneously with an Amplatzer Duct Occluder (size: 10-8 mm) (Figure 1C). After the successful implantation, no complications or residual shunt were found. Figure 1 A – 2D TTE revealed tunnel-like appearance of Gerbode defect between LVOT and RA in parasternal short-axis view (see arrow). B – Color Doppler echocardiography demonstrated clear systolic jet directed from the LVOT to the RA (see arrow). ... The Gerbode defect is a rare form of ventricular septal defect (VSD) that allows for communication between the left ventricle (LV) and RA. The congenital form of the LV-RA shunt is uncommon and the incidence is 0.08% of all catheterized congenital defects. Anatomically, two types of Gerbode defect are defined, supravalvular (less common) and subvalvular, depending on whether the defect in the membranous septum is above or below the tricuspid valve. Shunting from the LV to the RA mainly occurs in systole, resulting in a high-velocity jet by spectral Doppler between these chambers [1–3]. The LV-RA shunt is traditionally corrected surgically, but device closure is more comfortable new method. Six case reports of successful transcatheter closure in adults have been reported in the literature. Five patients were over 60 years old, and one patient was 22 years old. Five of these cases were performed after mitral valve surgery, and one was performed after VSD repair. Three communications were closed with Amplatzer duct occluders (ADO), one with VSD, and two with atrial septal defect occluders. Residual shunt of only trivial to mild degree was noted in four of those 6 cases. There were no major complications. All reported cases of catheter-based closure seemed to have 100% survival based on reviewing these case reports [4].

Abstract 12891: Mitral Valve Analysis Adding a Virtual Semi-Transparent Annulus Plane for Improved Visualization of Prolapsing Segments

Introduction: Three-dimensional echocardiography has improved the preoperative evaluation of mitral valve disease. Though, better tools to quantify the amount of prolapsing tissue is warranted. A novel 3D holographic display (Setred AS, Oslo, Norway) offer a 3-dimensional echocardiographic presentation without the need for stereo glasses. We have developed a semi-transparent annulus plane presentation that may better quantitate the prolapsing tissue. Hypothesis: We assessed the hypothesis that it is feasible to create a semi-automatic, semi-transparent annulus plane visualized on the holographic display, demonstrating the prolapsed segment that crosses the virtual mitral valve plane. Methods: Eight patients with degenerative mitral valve disease were analysed. Three-dimensional transthoracic echocardiography was obtained from an apical view and data was converted to the holographic display for further analysis. Findings were compared with visual inspection during surgery. A semi-automated tool was used to detect the annulus; placement of annulus points was done by clicking out points at small rotation intervals around a rotation center point while rotating around the long axis. After a full rotation, the plane was triangulated using a delaunay triangulation process and the annulus plane was visualized as a semi transparent blue surface. The dataset could then be shown from surgeons view in order to see where the valve crosses the visualized valve plane. Results: A total of 48 segments were analysed. We were able to obtain an annulus plane in all and by adding the annulus mitral valve plane, the prolapsing segments could be reproduced in all cases. Figure 1 shows representative recordings (surgeons view) demonstrating a P2 prolapse in the upper panel and a large A2 prolapse in the lower panel. Conclusion: In conclusion, the presentation of a semi-transparent annulus plane was feasible and the findings correlated well with that observed during surgery.

Normal mitral annulus dynamics and its relationships with left ventricular and left atrial function.

Mitral annulus (MA) geometry and dynamics are crucial for preserving normal mitral valve (MV) function. Static reference values for MA parameters have been reported, but the normal MA dynamics during the entire cardiac cycle remains controversial. MV full-volume datasets were obtained by three-dimensional transthoracic echocardiography from 50 healthy volunteers (18-74 years; 31 men) to assess MA changes in size and shape during entire cardiac cycle. Using simultaneous multiplanar review, projected MA area (MAA) and circumference (MAC), antero-posterior (AP) and anterolateral-posteromedial (ALPM) diameters, and sphericity index (SphI) were obtained at: mitral valve closure (MVC), mid- and end-systole (ES), early- (EDF) and late-diastolic filling, and end-diastole. MAA and AP diameter were the most "active" parameters, changing in all reference frames (p < 0.001). MAA and AP diameter started to contract before MVC (during the left atrial contraction), reaching their minimum at MVC. Maximum MAA occurred at ES, while maximum AP diameter and SphI occurred at EDF. MAA fractional shortening was 35 ± 10 %. AP diameter change was 25 ± 10 %. MAC, ALPM and SphI showed similar patterns during left ventricular (LV) systole, and remained unchanged during diastole. Fractional change was 35 ± 10 % for MAC, and 13 ± 8 % for ALPM diameter. Our study provides the normal dynamics of the MA during the entire cardiac cycle. It reveals "pre-systolic" contraction of the MA, related to left atrial (LA) contraction, and minimal MAA during early LV systole. Therefore, the normal MA dynamics relates to a "physiologic LA-LV coupling", and a complete MA contraction requires both and properly timed LA and LV systole.

Accuracy and precision of the ultrasound cardiac output monitor (USCOM 1A) in pregnancy: comparison with three-dimensional transthoracic echocardiography

Cardiac output (CO) monitoring is helpful in the assessment of critically ill pregnant women, but invasive monitors are often unsuitable for use. We aimed to measure agreement between the non-invasive ultrasound cardiac output monitor (USCOM) and three-dimensional transthoracic echocardiography (3D-TTE) in pregnant women. Healthy pregnant women from 25 weeks gestation onwards participated. In the left lateral position at rest, CO was measured with the USCOM and 3D-TTE. A single operator performed all USCOM measurements, with a different operator performing all echocardiography. Both were blinded to results from the other device. Each USCOM trace was analysed using two modes: flowtrace (FT) and touchpoint (TP). A second, blinded USCOM reading was taken to assess reproducibility. USCOM readings were obtained in 92, and 3D-TTE images in 85 participants. The mean CO was 5.7, 7.7, and 6.2 litre min(-1) measured by 3D-TTE, USCOM FT, and USCOM TP, respectively. USCOM bias was +2.0 litre min(-1) (FT) and +0.4 litre min(-1) (TP). Limits of agreement were -0.2 to +4.2 litre min(-1) (FT) and -1.4 to +2.3 litre min(-1) (TP). The mean percentage difference was 32.6% (FT) and 31.4% (TP) for CO and 27.0% (FT) and 27.5% (TP) for stroke volume. Intraclass correlation between repeated USCOM readings was 0.9 (FT) and 0.86 (TP). USCOM has acceptable agreement with 3D-TTE for the measurement of CO in pregnancy. The positive bias of the USCOM, particularly in the FT mode, may be due to the hyperdynamic cardiovascular state in pregnancy. We suggest using the TP mode in this patient population.

Left atrial function in patients with mitral valve regurgitation.

The purpose of this study was to assess left atrial (LA) function and myocardial mechanics in patients with degenerative mitral regurgitation (MR). Eighty patients with degenerative MR and twenty control subjects were included prospectively. LA volume (LAV) and right atrial (RA) volume (RAV) were measured with three-dimensional transthoracic echocardiography at three phases of the cardiac cycle as maximal volume (LAVmax and RAVmax), minimal volume (LAVmin and RAVmin), and volume before atrial contraction (LAVpre-A and RAVpre-A). From these volumes, active stroke volume (SV), distensibility, and emptying fraction were calculated. LA strain and strain rate were measured with vector velocity imaging on four- and two-chamber views. Left ventricular (LV) filling pressures were increased in patients with severe MR (E/E': 16 ± 4 vs. 10 ± 3 in control subjects). LAVmax, LAVmin, and LAVpre-A all increased with increasing MR volume. As LAVpre-A increased, both LA total SV (r = 0.68, P < 0.001) and passive filling volume (r = 0.76, P < 0.001) increased. LA active SV increased with LAVpre-A up to a certain point, upon which it decreased despite further increased LAVpre-A (r = 0.53, P < 0.001). LA late negative strain decreased with increasing MR volume. A positive correlation existed between LA late negative strain and LA active emptying fraction (r = 0.55, P < 0.001). In contrast, RA function was comparable between groups. In conclusion, LA contractility (active SV) increased in response to an increase in LA preload (LAVpre-A) up to a point beyond which LA contractility (active SV) decreased. Whether this is due to working of the LA at the descending limb of the Frank-Starling curve or mainly due to changes in afterload still remains unclear.

Quantitative Analysis of Mitral Annular Geometry and Function in Healthy Volunteers Using Transthoracic Three-Dimensional Echocardiography

Quantitative assessment of the mitral annulus provides information regarding the pathophysiology of mitral regurgitation and aids in the planning of reparative surgery. Three-dimensional (3D) transthoracic echocardiographic data sets acquired with current scanners have enough spatial and temporal resolution to allow the quantitative analysis of the mitral annulus. Accordingly, the authors performed (1) a validation study to assess the agreement of quantitative analysis of the mitral annulus performed on 3D transthoracic echocardiography (TTE) and 3D transesophageal echocardiography (TEE) and (2) a normative study to obtain the reference values of 3D transthoracic echocardiographic parameters for mitral annular (MA) geometry and dynamics. Mitral valve data sets were obtained by 3D TEE and 3D TTE in 30 consecutive patients with clinically indicated TEE (validation study) and 3D TTE in 224 healthy volunteers (aged 18-76 years) (normative study). In the validation study, MA measurements obtained by 3D TTE were similar to those obtained by 3D TEE (P = NS). In the normative study, MA analysis by 3D TTE was feasible (94.5%) and reproducible (intraclass correlation coefficient = 0.78-0.97). MA diameters, area, and circumference were correlated with body surface area (r > 0.50 for all) but not with age. Men had larger MA areas than women (4.9 ± 1.0 vs 4.5 ± 0.7 cm(2)/m(2), P = .004). During systole, MA area decreased by 29 ± 5%. This decrease was related mainly to anteroposterior diameter shortening (20 ± 7%). MA quantitative analysis by 3D TTE was accurate compared with 3D TEE in unselected patients with mitral valve disease. In healthy subjects, it was highly feasible and reproducible. The availability of reference values for MA geometry and dynamics may foster the implementation of MA quantitative analysis by 3D TTE in clinical settings.

Interventional Echocardiography

Echocardiography guidance for interventions in the catheterization laboratory allows for reduction in radiation exposure from fluoroscopy as well as superior anatomic definition and visualization. The additional information provided over fluoroscopy has translated into an increasing use during interventional procedures. Procedures such as transeptal puncture, percutaneous valvular interventions, myocardial biopsy, echo-guided pericardiocentesis and other interventions have evolved to a complexity level that requires combined echocardiographic and fluoroscopic guidance. Different imaging modalities are utilized in the catheterization laboratory including intracardiac echocardiography, two-dimensional (2D) or three-dimensional (3D) transthoracic echocardiography, and 2D or 3D transesophageal echocardiography. This review is intended to provide an overall summary of the impact echocardiography has had in the catheterization laboratory. We will describe how echocardiography is utilized to guide a diverse array of interventional procedures, emphasizing specific practical issues with respect to echocardiographic guidance of interventional procedures and also pointing out the limitations of echocardiography.