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Background:Determining infectious cross-transmission events in healthcare settings involves manual surveillance of case clusters by infection control personnel, followed by strain typing of clinical/environmental isolates suspected in said clusters. Recent advances in genomic sequencing and cloud computing now allow for the rapid molecular typing of infecting isolates.Objective:To facilitate rapid recognition of transmission clusters, we aimed to assess infection control surveillance using whole-genome sequencing (WGS) of microbial pathogens to identify cross-transmission events for epidemiologic review.Methods:Clinical isolates ofStaphylococcus aureus,Enterococcus faecium,Pseudomonas aeruginosa, andKlebsiella pneumoniaewere obtained prospectively at an academic medical center, from September 1, 2016, to September 30, 2017. Isolate genomes were sequenced, followed by single-nucleotide variant analysis; a cloud-computing platform was used for whole-genome sequence analysis and cluster identification.Results:Most strains of the 4 studied pathogens were unrelated, and 34 potential transmission clusters were present. The characteristics of the potential clusters were complex and likely not identifiable by traditional surveillance alone. Notably, only 1 cluster had been suspected by routine manual surveillance.Conclusions:Our work supports the assertion that integration of genomic and clinical epidemiologic data can augment infection control surveillance for both the identification of cross-transmission events and the inclusion of missed and exclusion of misidentified outbreaks (ie, false alarms). The integration of clinical data is essential to prioritize suspect clusters for investigation, and for existing infections, a timely review of both the clinical and WGS results can hold promise to reduce HAIs. A richer understanding of cross-transmission events within healthcare settings will require the expansion of current surveillance approaches.

Accurate localization of mitral valve prolapse (MVP) is crucial for surgical planning. Despite improved visualization of the mitral valve by three-dimensional transesophageal echocardiography, image interpretation remains expertise dependent. Manual construction of mitral valve topographic maps improves diagnostic accuracy but is time-consuming and requires substantial manual input. A novel computer-learning technique called Anatomical Intelligence in ultrasound (AIUS) semiautomatically tracks the annulus and leaflet anatomy for parametric analysis. The aims of this study were to examine whether AIUS could improve accuracy and efficiency in localizing MVP among operators with different levels of experience.Two experts and four intermediate-level echocardiographers (nonexperts) retrospectively performed analysis of three-dimensional transesophageal echocardiographic images to generate topographic mitral valve models in 90 patients with degenerative MVP. All echocardiographers performed both AIUS and manual segmentation in sequential weekly sessions. The results were compared with surgical findings.Manual segmentation by nonexperts had significantly lower sensitivity (60% vs 90%, P .001), specificity (91% vs 97%, P = .001), and accuracy (83% vs 95%, P .001) compared with experts. AIUS significantly improved the accuracy of nonexperts (from 83% to 89%, P = .003), particularly for lesions involving the A3 (from 81% to 94%, P = .006) and P1 (from 78% to 88%, P = .001) segments, presumably related to anatomic variants of the annulus that made tracking more challenging. AIUS required significantly less time for image analysis by both experts (1.9 ± 0.7 vs 9.9 ± 3.5 min, P .0001) and nonexperts (5.0 ± 0.5 vs 13 ± 1.5 min, P .0001), especially for complex lesions.Anatomic assessment of mitral valve pathology by three-dimensional transesophageal echocardiography is experience dependent. A semiautomated algorithm using AIUS improves accuracy and efficiency in localizing MVP by less experienced operators.

Background 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. Methods 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. Results 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 (5 min) was significantly less compared with the manual method (27 min) ( P r = 0.94–0.99), and test-retest variability of left chamber parameters was low (3.5%–4.8%). Conclusions 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.

Objectives The goal of this study was to test the feasibility and accuracy of an automated algorithm that simultaneously quantifies 3-dimensional (3D) transthoracic echocardiography (TTE)-derived left atrial (LA) and left ventricular (LV) volumes and left ventricular ejection fraction (LVEF). Conventional manual 3D TTE tracings and cardiac magnetic resonance (CMR) images were used as a reference for comparison. Background Cardiac chamber quantification from 3D TTE is superior to 2D TTE measurements. However, integration of 3D quantification into clinical practice has been limited by time-consuming workflow and the need for 3D expertise. A novel automated software was developed that provides LV and LA volumetric quantification from 3D TTE datasets that reflect real-life manual 3-dimensional echocardiography measurements and values comparable to CMR. Methods A total of 159 patients were studied in 2 separate protocols. In protocol 1, 94 patients underwent 3D TTE imaging (EPIQ, iE33, X5-1, Philips Healthcare, Andover, Massachusetts) covering the left atrium and left ventricle. LA and LV volumes and LVEF were obtained using the automated software (HeartModel, Philips Healthcare) with and without contour correction, and compared with the averaged manual 3D volumetric measurements from 3 readers. In protocol 2, automated measurements from 65 patients were compared with a CMR reference. The Pearson correlation coefficient, Bland-Altman analysis, and paired Student t tests were used to assess inter-technique agreement. Results Correlations between the automated and manual 3D TTE measurements were strong (r = 0.87 to 0.96). LVEF was underestimated and automated LV end-diastolic, LV end-systolic, and LA volumes were overestimated compared with manual measurements. Agreement between the automated analysis and CMR was also strong (r = 0.84 to 0.95). Test–retest variability was low. Conclusions Automated simultaneous quantification of LA and LV volumes and LVEF is feasible and requires minimal 3D software analysis training. The automated measurements are not only comparable to manual measurements but also to CMR. This technique is highly reproducible and timesaving, and it therefore promises to facilitate the integration of 3D TTE-based left-heart chamber quantification into clinical practice.

Background— Few data exist on the relation of the 3-dimensional morphology of mitral valve and degree of mitral regurgitation (MR) in mitral valve prolapse. Methods and Results— Real-time 3-dimensional transesophageal echocardiography of the mitral valve was acquired in 112 subjects, including 36 patients with mitral valve prolapse and significant MR (≥3+; MR+ group), 32 patients with mitral valve prolapse but no or mild MR (≤2+; MR− group), 12 patients with significant MR resulting from nonprolapse pathologies (nonprolapse group), and 32 control subjects. The 3-dimensional geometry of mitral valve apparatus was measured with dedicated quantification software. Compared with the normal and MR− groups, the MR+ group had more dilated mitral annulus ( P P P P P P P 20%, 15%–20%, and P =0.004). Leaflet billow volume increased exponentially with decreasing AHCWR in patients without chordal rupture ( r 2 =0.66, P r 2 =0.74, P r 2 =0.44, P P =0.0004) was strongly associated with significant MR in mitral valve prolapse. Conclusion— Flattening of the annular saddle shape is associated with progressive leaflet billowing and increased frequencies of chordal rupture and may be important in the pathogenesis of MR in mitral valve prolapse.

Background: Assessment of right ventricular (RV) function is difficult due to the complex shape of this chamber. Tricuspid annular plane systolic excursion (TAPSE) measured with M-mode echocardiography is frequently used as an index of RV function. However, its accuracy may be limited by ultrasound beam misalignment. We hypothesized that two-dimensional (2D) speckle tracking echocardiography (STE) could provide more accurate estimates of RV function. Accordingly, STE was used to quantify tricuspid annular displacement (TAD), from which RV longitudinal shortening fraction (LSF) was calculated. These STE derived indices were compared side-by-side with M-mode TAPSE measurements against cardiac magnetic resonance (CMR) derived RV ejection fraction (EF). Methods: Echocardiography (Philips iE33, four-chamber view) and CMR (Siemens, 1.5 T) were performed on the same day in 63 patients with a wide range of RV EF (23–70% by CMR). TAPSE was measured using M-mode echocardiography. TAD and RV LSF were obtained using STE analysis (QLAB CMQ, Philips). TAPSE, TAD and RV LSF values were compared with RV EF obtained from CMR short axis stacks. Results: STE analysis required

Background Left ventricular (LV) ejection fraction (EF) by transthoracic two-dimensional echocardiography is time-intensive and highly dependent on image quality. Mitral annular displacement (MAD) qualitatively correlates with EF and can be measured in patients with poor image quality and dropout. The authors hypothesized that speckle-tracking echocardiography (STE)–derived MAD could quantify EF accurately and tested this hypothesis using cardiac magnetic resonance (CMR) as a reference. Methods One hundred eighteen patients undergoing clinical transthoracic echocardiography were screened, and 110 whose mitral annuli was sufficiently well-defined irrespective of LV endocardial visualization underwent CMR within 6 days (85 of 110 in 1 day). Reference CMR EF values were obtained using standard methodology. STE was used to track annular motion throughout the cardiac cycle in the apical 2-chamber and 4-chamber views. To establish the relationship between MAD and CMR EF and to obtain a formula to estimate EF from MAD, regression analysis was performed in a study group of 60 patients with a wide range of EFs. This formula was then used in an independent test group of 50 patients by comparing estimated MAD EF against CMR EF values using Pearson's correlation and Bland-Altman analyses. Results In the study group, STE MAD correlated highly with CMR EF and resulted in a formula relating MAD to EF. In the test group, estimated EF correlated well with CMR EF (4-chamber, R 2 = 0.64; 2-chamber, R 2 = 0.55), with near-zero bias and acceptable limits of agreement. Intraobserver and interobserver variability were between 5.8% and 12.7%. Conclusions STE MAD is a clinically useful tool for quick, easy, robust, and accurate estimates of EF irrespective of LV endocardial definition.

Background Aging affects left atrial (LA) function, which can be assessed by two-dimensional (2D) speckle tracking echocardiography (STE). The aim of this study was to determine (1) the feasibility and accuracy of measuring LA volume with 2DSTE and (2) the effects of aging on LA function. Methods 2DSTE of the LA was acquired from the apical 4-chamber view (frame rate: 63 ± 11 /sec, iE33) using prototype speckle tracking software (QLAB, Philips Medical Systems, Andover, MA) in 140 healthy volunteers (3-79 years, 74 men). LA wall was tracked on a frame-by-frame basis, and LA volume waveforms were generated. Maximum LA volume (LAVmax) and minimal LA volume (LAVmin), and the LA volume before atrial contraction (LAVpre-a) were measured. Passive emptying percent of total emptying (LA conduit function) and active emptying percent of total emptying (booster function) were calculated as ([LAVmax-LAVpre-a]/[LAVmax-LAVmin]) × 100 and ([LAVa-LAVmin]/[LAVmax-LAVmin]) × 100. Results Adequate LA volume waveforms were obtained in all subjects. A good correlation was obtained between speckle tracking-derived LA volume measurements and manually traced LA volume measurements of the identical 2D image (LAVmax: r = 0.93, P .001, LAVmin: r = 0.88, P .001, LAVpre-a: r = 0.92, P .001). Passive and active emptying indices had a significant age dependency ( r = 0.80, P .001). Overall, passive emptying accounted for 67% of the total LA emptying ranging from 83% in the youngest to 42% in the oldest decade. Conclusion Aging significantly affects LA conduit and booster function. 2DSTE can effectively and easily measure LA volume and has a potential for the noninvasive assessment of LA function.

The aim of this study was to test the ability of a new algorithm to accurately measure point-to-point Lagrangian strain (LS) and local rotation (ROT). Change in distance between 2 separate regions of interest (ROIs) can theoretically be computed with speckle tracking (SpT) and used to calculate LS in any tissue location with angle independence and high spatial resolution. Similarly, tracking an ROI relative to a fixed point should provide an estimate of ROT.Two dynamic phantoms (60 beats/min) were scanned in short axis at frame rates of 30, 60, and 90 Hz. To estimate LS, 2 ROIs were positioned immediately beneath the inner and outer borders of the superior wall of the first phantom and tracked using SpT. LS derived from SpT (SpT-LS) was compared with LS measured by sonomicrometers placed on the inner and outer walls of the phantom (SN-LS). To estimate ROT, the rotational vectors around the centroid of a second phantom were calculated for 3 epicardial bead targets imaged with gated computed tomography (CT) and compared with measurements derived from SpT.There was a significant correlation between SpT-LS and SN-LS at 30 Hz (R(2) = 0.99; P.0001), 60 Hz (R(2) = 0.98; P.0001), and 90 Hz (R(2) = 0.99; P.0001). There was also a significant correlation between ROT derived from SpT and ROT derived from CT: R(2) = 0.97 (P.0001) at 30 Hz, R(2) = 0.95 (P.0001) at 60 Hz, and R(2) = 0.98 (P.0001) at 90 Hz.Point-to-point SpT permits the determination of LS between 2 distinct tissue regions as well as ROT measurement of specific tissue regions without the need for border detection.

Objectives Our study goals were to evaluate the 3-dimensional matrix array transesophageal echocardiographic (3D-MTEE) probe by assessing the image quality of native valves and other intracardiac structures. Background Because 3-dimensional transesophageal echocardiography with gated rotational acquisition is not used routinely as the result of artifacts, lengthy acquisition, and processing, a 3D-MTEE probe was developed (Philips Medical Systems, Andover, Massachusetts). Methods In 211 patients, 3D-MTEE zoom images of the mitral valve (MV), aortic valve, tricuspid valve, interatrial septum, and left atrial appendage were obtained, followed by a left ventricular wide-angled acquisition. Images were reviewed and graded off-line (Xcelera with QLAB software, Philips Medical Systems). Results Excellent visualization of the MV (85% to 91% for all scallops of both MV leaflets), interatrial septum (84%), left atrial appendage (86%), and left ventricle (77%) was observed. Native aortic and tricuspid valves were optimally visualized only in 18% and 11% of patients, respectively. Conclusions The use of 3D-MTEE imaging, which is feasible in most patients, provides superb imaging of native MVs, which makes this modality an excellent choice for MV surgical planning and guidance of percutaneous interventions. Optimal aortic and tricuspid valve imaging will depend on further technological developments. Fast acquisition and immediate online display will facilitate wider acceptance and routine use in clinical practice.

We studied the usefulness and reproducibility of real-time 3-dimensional (3D) echocardiography (RT3DE) for evaluating left ventricular (LV) dyssynchrony, and compared its results with Doppler tissue image (DTI) indices. Full-volume RT3DE data sets and 2-dimensional DTI from apical window were obtained in 122 participants. Using fast 3D border detection software, time to minimum systolic volume (Tmsv) was semiautomatically calculated in each region from a 17-segment model. Several dyssynchrony indices were then calculated: Tmsv-16SD, the SD of Tmsv in 16 of 17 segments, excluding the apical cap; Tmsv-12SD, the SD of Tmsv of 6 basal and 6 middle segments; and Tmsv-6SD, the SD of Tmsv of 6 basal segments. These dyssynchrony indices of RT3DE were then compared with two dyssynchrony indices measured by DTI: time to peak systolic velocity (TTPV)-12SD, the SD of time to peak systolic velocity of 12 LV segments; and time to cross over point of temporal axis (TTCO)-12SD, the SD of time to crossover point of temporal axis. RT3DE data was quantitatively analyzed in 117 of 122 patients. Tmsv-16SD (35 +/- 34 milliseconds) was significantly longer compared with Tmsv-12SD (27 +/- 30 milliseconds, P < .001) or Tmsv-6SD (23 +/- 28 milliseconds, P < .001). Tmsv-16SD increased significantly with the severity of LV systolic dysfunction. Fair correlation was noted among TTPV-12SD, TTCO-12SD, and Tmsv-16SD (r = 0.71, r = 0.73) and between Tmsv-16SD and LV ejection fraction (r = 0.80). Concordance rate between TTPV-12SD and Tmsv-16SD for detecting LV dyssynchrony was 79%. The corresponding value between TTCO-12SD and Tmsv-16SD was 80%. In conclusion, Tmsv-16SD correlated well with DTI-derived LV dyssynchrony indices. In addition to LV remodeling, fast border detection RT3DE provides useful parameters for evaluating LV dyssynchrony.

Clinical environments are rapidly changing to demand higher throughputs, lower cost, and more successful clinical outcomes. Echocardiography has, in turn, been forced to evolve. In addition to providing real-time imaging at a relatively low cost and risk to the patient, it now also provides rapid and robust measurements that aid in monitoring, diagnosis, and intervention. These advancements of measurements and analysis are achieved through automation afforded by Anatomical Intelligence, which is an automatic recognition and segmentation of anatomic structures within an echo image by a trained algorithm. Early versions of Anatomical Intelligence have focused on expediting the workflow of an expert sonographer, whereas, future versions will focus on enabling novice sonographers to perform tasks previously only achievable by experts.

Background Accurate diagnosis of mitral regurgitation (MR) severity is central to proper treatment. Although numerous approaches exist, an accurate, gold-standard clinical technique remains elusive. The authors previously reported on the initial development and demonstration of the automated three-dimensional (3D) field optimization method (FOM) algorithm, which exploits 3D color Doppler ultrasound imaging and builds on existing MR quantification techniques. The aim of the present study was to extensively validate 3D FOM in terms of accuracy, ease of use, and repeatability. Methods Three-dimensional FOM was applied to five explanted ovine mitral valves in a left heart simulator, which were systematically perturbed to yield a total of 29 unique regurgitant geometries. Three-dimensional FOM was compared with a gold-standard flow probe, as well as the most clinically prevalent MR volume quantification technique, the two-dimensional (2D) proximal isovelocity surface area (PISA) method. Results Overall, 3D FOM overestimated and 2D PISA underestimated MR volume, but 3D FOM error had smaller magnitude (5.2 ± 9.9 mL) than 2D PISA error (−6.9 ± 7.7 mL). Two-dimensional PISA remained superior in diagnosis for round orifices and especially mild MR, as predicted by ultrasound physics theory. For slit-type orifices and severe MR, 3D FOM showed significant improvement over 2D PISA. Three-dimensional FOM processing was technically simpler and significantly faster than 2D PISA and required fewer ultrasound acquisitions. Three-dimensional FOM did not show significant interuser variability, whereas 2D PISA did. Conclusions Three-dimensional FOM may provide increased clinical value compared with 2D PISA because of increased accuracy in the case of complex or severe regurgitant orifices as well as its greater repeatability and simpler work flow.

Aims Determination of left ventricular (LV) volumes and ejection fraction (EF) from two-dimensional echocardiographic (2DE) images is subjective, time-consuming, and relatively inaccurate because of foreshortened views and the use of geometric assumptions. Our aims were (1) to validate a new method for rapid, online measurement of LV volumes from real-time three-dimensional echocardiographic (RT3DE) data using cardiac magnetic resonance (CMR) as the reference and (2) to compare its accuracy and reproducibility with standard 2DE measurements. Methods and results CMR, 2DE, and RT3DE datasets were obtained in 50 patients. End-systolic and end-diastolic volumes (ESV and EDV) were calculated from the 2DE images using biplane method of disks. ES and ED RT3DE datasets were analysed using prototype software designed to automatically detect the endocardial surface using a deformable shell model and calculate ESV and EDV from voxel counts. 2DE and RT3DE-derived volumes were compared with CMR (linear regression, Bland–Altman analysis). In most patients, analysis of RT3DE data required

BACKGROUND: There is no current acceptable approach for intracardiac beating-heart interventions. We have adapted real-time 3-dimensional echocardiography with specialized instrumentation to facilitate beating-heart repair of atrial septal defects and mitral valve plasty to investigate the feasibility of real-time 3-dimensional echocardiography-guided cardiac surgery. METHODS: In experiment I a modified real-time 3-dimensional echocardiography system with x4 matrix transducer was compared with 2-dimensional echocardiography in the performance of common surgical tasks. Completion times, deviation from an ideal trajectory, and an echogenic target were measured. In experiment II porcine atrial septal defects were closed with an original semiautomatic suturing device (n = 4) and with a 5-mm endoscopic stapler and a pericardial or polytetrafluoroethylene patch (n = 4). In experiment III a pulsatile porcine mitral valve model was developed, and suture placement through the anterior and posterior mitral leaflets was performed (n = 8). During all experiments, the operator was blinded to the target and operated on only with ultrasonic guidance. RESULTS: In experiment I, compared with 2-dimensional echocardiographic guidance, completion times improved by 21% ( P

Background— Left ventricular (LV) mass is an important predictor of morbidity and mortality, especially in patients with systemic hypertension. However, the accuracy of 2D echocardiographic LV mass measurements is limited because acquiring anatomically correct apical views is often difficult. We tested the hypothesis that LV mass could be measured more accurately from real-time 3D (RT3D) data sets, which allow offline selection of nonforeshortened apical views, by comparing 2D and RT3D measurements against cardiac MR (CMR) measurements. Methods and Results— Echocardiographic imaging was performed (Philips 7500) in 21 patients referred for CMR imaging (1.5 T, GE). Apical 2- and 4-chamber views and RT3D data sets were acquired and analyzed by 2 independent observers. The RT3D data sets were used to select nonforeshortened apical 2- and 4-chamber views (3DQ-QLAB, Philips). In both 2D and RT3D images, LV long axis was measured; endocardial and epicardial boundaries were traced, and mass was calculated by use of the biplane method of disks. CMR LV mass values were obtained through standard techniques (MASS Analysis, GE). The RT3D data resulted in significantly larger LV long-axis dimensions and measurements of LV mass that correlated with CMR better ( r =0.90) than 2D ( r =0.79). The 2D technique underestimated LV mass (bias, 39%), whereas RT3D measurements showed only minimal bias (3%). The 95% limits of agreement were significantly wider for 2D (52%) than RT3D (28%). Additionally, the RT3D technique reduced the interobserver variability (37% to 7%) and intraobserver variability (19% to 8%). Conclusions— RT3D imaging provides the basis for accurate and reliable measurement of LV mass.

After myocardial infarction (MI), the border zone expands chronically, causing ventricular dilatation and congestive heart failure (CHF). In an ovine model ( n = 4) of anteroapical MI that results in CHF, contrast echocardiography was used to image short-axis left ventricular (LV) cross sections and identify border zone myocardium before and after coronary artery ligation. In the border zone at end systole, the LV endocardial curvature ( K) decreased from 0.86 ± 0.33 cm−1 at baseline to 0.35 ± 0.19 cm−1 at 1 h ( P < 0.05), corresponding to a mean decrease of 55%. Also in the border zone, the wall thickness ( h) decreased from 1.14 ± 0.26 cm at baseline to 1.01 ± 0.25 cm at 1 h ( P < 0.05), corresponding to a mean decrease of 11%. By Laplace's law, wall stress is inversely proportional to the product K · h. Therefore, a 55% decrease in K results in a 122% increase in circumferential stress; a 11% decrease in h results in a 12% increase in circumferential stress. These findings indicate that after MI, geometric changes cause increased dynamic wall stress, which likely contributes to border zone expansion and remodeling.

As a stand-alone imaging modality, two-dimensional (2D) ultrasound (US) can only guide basic interventional tasks due to the limited spatial orientation information contained in these images. High-resolution real-time three-dimensional (3D) US can potentially overcome this limitation, thereby expanding the applications for US-guided procedures to include intracardiac surgery and fetal surgery, while potentially improving results of solid organ interventions such as image-guided breast, liver or prostate procedures. The following study examines the benefits of real-time 3D US for performing both basic and complex image-guided surgical tasks.Seven surgical trainees performed three tasks in an acoustic testing tank simulating an image-guided surgical environment using 2D US, biplanar 2D US, and 3D US for guidance. Surgeon-controlled US imaging was also tested. The evaluation tasks were (1) bead-in-hole navigation; (2) bead-to-bead navigation; and (3) clip fixation. Performance measures included completion time, tool tip trajectory, and error rates, with endoscope-guided performance serving as a gold-standard reference measure for each subject.Compared to 2D US guidance, completion times decreased significantly with 3D US for both bead-in-hole navigation (50%, p = 0.046) and bead-to-bead navigation (77%, p = 0.009). Furthermore, tool-tip tracking for bead-to-bead navigation demonstrated improved navigational accuracy using 3D US versus 2D US (46%, p = 0.040). Biplanar 2D imaging and surgeon-controlled 2D US did not significantly improve performance as compared to conventional 2D US. In real-time 3D mode, surgeon-controlled imaging and changes in 3D image presentation made by adjusting the perspective of the 3D image did not diminish performance. For clip fixation, completion times proved excessive with 2D US guidance (240 s). However, with real-time 3D US imaging, completion times and error rates were comparable to endoscope-guided performance.Real-time 3D US can guide basic surgical tasks more efficiently and accurately than 2D US imaging. Real-time 3D US can also guide more complex surgical tasks which may prove useful for procedures where optical imaging is suboptimal, as in fetal surgery or intracardiac interventions.

Mitral valve regurgitation (MR) is among the most prevalent and significant valve problems in the Western world. Echocardiography plays a significant role in the diagnosis of degenerative valve disease. However, a simple and accurate means of quantifying MR has eluded both the technical and clinical ultrasound communities. Perhaps the best clinically accepted method used today is the 2-D proximal isovelocity surface area (PISA) method. In this study, a new quantification method using 3-D color Doppler ultrasound, called the field optimization method (FOM), is described. For each 3-D color flow volume, this method iterates on a simple fluid dynamics model that, when processed by a model of ultrasound physics, attempts to agree with the observed velocities in a least-squares sense. The output of this model is an estimate of the regurgitant flow and the location of its associated orifice. To validate the new method, in vitro experiments were performed using a pulsatile flow loop and different geometric orifices. Measurements from the FOM and from 2-D PISA were compared with measurements made with a calibrated ultrasonic flow probe. Results show that the new method has a higher correlation to the truth data and has lower inter- and intra-observer variability than the 2-D PISA method.

p ROLONGED LIFE, improved quality of life, increased exercise tolerance, and relief of symptoms are the measures of outcome for cardiac surgery and need to be attained despite decreasing resources, increasing patient age and comorbidity, and increasing complexity of the operative procedure.1 The achievement of these benefits requires a coordinated and systematic approach to postoperative care under the medical direction of a staff physician. Historically, the postoperative care of cardiac patients was provided by the attending surgeon at the bedside or, unfortunately too often, by the attending surgeon from a distant location (ie, operating room or outpatient clinic). Consistent medical direction of critically ill patients via telephone calls, pager systems, or courier is fraught with difficulties and exposes the patient to unnecessary risks. In an era when the surgical team (ie, cardiac surgeon and cardiac anesthesiologist) must return to the operating room soon after the patient arrives to the intensive care unit (ICU), the presence of a physician dedicated to postoperative medical management becomes mandatory. This premise is increasingly evident as the scope of cardiac surgery increases and the complexity of the cardiac surgical patients requires hands-on physician involvement for the immediate and intermediate postoperative period.

A novel simple method of extraction, separation, identification and quantification of nicardipine in human plasma samples was completely studied. The human plasma samples were initially purified by solid-phase extraction (SPE) using a C 18 cartridge. The extracted samples were separated and nicardipine present in the samples was quantified by high-performance liquid chromatography (HPLC) on a reversed-phase C 18 column employing a mobile phase consisting of 60% (v/v) acetonitrile in 0.02 M NaH 2 PO 4 with pH of 6.3 and a variable wavelength UV detector set at 254 nm. The recovery of nicardipine from plasma samples using selective SPE was 91±6.0% and had less interfering compounds in the HPLC analysis compared to the use of liquid–liquid (L/L) extraction. In the HPLC analysis, examining the effect of pH values of the mobile phase on the capacity factor ( k ′) of nicardipine revealed a method for selecting a critical k ′ value of nicardipine to eliminate interfering peaks near the peak specific to the analyte. This method for quantification of nicardipine in human plasma samples was suitable for studying the pharmacokinetic profile of nicardipine administered as an intravenous bolus to cardiac surgical patients.

article i nfo Introduction:Infunctionalmitralregurgitation(FMR),effectiveregurgitantorificearea(EROA)displaysadynam- ic pattern. The impact of dynamic changes of annulus dysfunction and leaflets tenting on phasic EROA was ex- plored with real-time three-dimensional transesophageal echocardiography (RT3D-TEE). Methods: RT3D-TEE was performed in 52 FMR patients and 30 controls. Mitral annulus dimensions and leaflets tenting were measured throughout systole (TomTec, Germany). Phasic EROA was measured by proximal isovelocity surface area (PISA) method. Results: Mitral annulus had the minimal area and an oval shape with saddle configuration during early systole in controls, which enlarged and became round and flattened towards mid and late systole (P b 0.05). In contrast, annulus in FMR was significantly larger, rounder and flatter (P b 0.001), which further dilated and became more flattened at late systole (P b 0.05 vs control). Leaflet tenting height in FMR decreased in mid systole and remains unchanged towards late systole. The leaflet tenting volume peaked at early and late systole with a mid-systolic trough in both FMR and controls. But tenting volume of patients with FMR was significantly larger than that of controls (all P b 0.001 vs control in whole systole). Further analysis demonstrated that early tenting volume (β value = 0.053, P b 0.05) was a predictor of early EROA, whereas late tenting volume (β value = 0.031, P b 0.05) and late annular displacement velocity were predictors of late EROA. Conclusions: The early and late peak EROAs of FMR was primarily contributed by tenting volume at early systole and late systole respectively. These findings would beof value toconsiderin interventions aimed atreducing the severity of FMR.

Background Differentiating between mitral valve (MV) prolapse (MVP) and MV billowing (MVB) on two-dimensional echocardiography is challenging. The aim of this study was to test the hypothesis that color-coded models of maximal leaflet displacement from the annular plane into the atrium derived from three-dimensional transesophageal echocardiography would allow discrimination between these lesions. Methods Three-dimensional transesophageal echocardiographic imaging of the MV was performed in 50 patients with ( n = 38) and without ( n = 12) degenerative MV disease. Definitive diagnosis of MVP versus MVB was made using inspection of dynamic three-dimensional renderings and multiple two-dimensional cut planes extracted from three-dimensional data sets. This was used as a reference standard to test an alternative approach, wherein the color-coded parametric models were inspected for integrity of the coaptation line and location of the maximally displaced portion of the leaflet. Diagnostic interpretations of these models by two independent readers were compared with the reference standard. Results In all cases of MVP, the color-coded models depicted loss of integrity of the coaptation line and maximal leaflet displacement extending to the coaptation line. MVB was depicted by preserved leaflet apposition with maximal displacement away from the coaptation line. Interpretation of the 50 color-coded models by novice readers took 5 to 10 min and resulted in good agreement with the reference technique (κ = 0.81 and κ = 0.73 for the two readers). Conclusions Three-dimensional color-coded models provide a static display of MV leaflet displacement, allowing differentiation between MVP and MVB, without the need to inspect multiple planes and while taking into account the saddle shape of the mitral annulus.

Cardiac chamber quantification from 3D transthoracic echocardiography (3D TTE) has been shown to be superior to measurements obtained from 2D studies. However, integration of 3D TTE into routine clinical practice has been limited by the time-consuming workflow and need for 3D expertise. We assessed

Coarctation of aorta (CoA) is a critical congenital heart defect (CCHD) that requires accurate and immediate diagnosis and treatment. Current newborn screening methods to detect CoA lack both in sensitivity and specificity, and when suspected in a newborn, it must be confirmed using specialized imaging and expert diagnosis, both of which are usually unavailable at tertiary birthing centers. We explore the feasibility of applying machine learning methods to reliably determine the presence of this difficult-to-diagnose cardiac abnormality from ultrasound image data. We propose a framework that uses deep learning-based machine learning methods for fully automated detection of CoA from two-dimensional ultrasound clinical data acquired in the parasternal long axis view, the apical four chamber view, and the suprasternal notch view. On a validation set consisting of 26 CoA and 64 normal patients our algorithm achieved a total error rate of 12.9% (11.5% false-negative error and 13.6% false-positive error) when combining decisions of classifiers over three standard echocardiographic view planes. This compares favorably with published results that combine clinical assessments with pulse oximetry to detect CoA (71% sensitivity).

FUNDAMENTO: A alta e crescente prevalência de Cardiomiopatia Dilatada (CMD) representa sério problema de saúde pública. Novas tecnologias vêm sendo utilizadas objetivando diagnósticos mais sofisticados, que melhorem a abordagem terapêutica. Nesse cenário, o Speckle Tracking (STE) utiliza marcadores miocárdicos naturais para analisar a deformação sistólica do Ventrículo Esquerdo (VE). OBJETIVO: Mensurar o strain transmural longitudinal global (SG) do VE através do STE em pacientes com CMD grave, comparando os resultados com indivíduos normais e com parâmetros ecocardiográficos consagrados para análise da função sistólica do VE, validando o método nessa população. MÉTODOS: Foram estudados 71 pacientes com CMD grave, (53 ± 12a, 72% homens) e 20 controles (30 ± 8a, 45% homens). Foram obtidos os volumes e a FEVE pela ecocardiografia bi e tridimensional, parâmetros do Doppler, Doppler tecidual e o SG pelo STE. RESULTADOS: Comparados ao grupo controle, os volumes do VE foram maiores no grupo CMD; entretanto, a FEVE e velocidade de pico da onda E foram menores neste último. O índice de performance miocárdica foi maior entre os pacientes. As velocidades do miocárdio pelo Doppler tecidual (S', e', a') foram consideravelmente menores e a relação E/e' foi maior no grupo CMD. O SG apresentou-se diminuído no grupo CMD (-5,5% ± 2,3%), em relação aos controles (-14,0% ± 1,8%). CONCLUSÃO: No presente estudo, o SG foi significativamente menor nos pacientes com CMD grave, abrindo novas perspectivas para abordagens terapêuticas nessa população específica. BACKGROUND: The high and increasing prevalence of Dilated Cardiomyopathy (DCM) represents a serious public health problem. New technologies are being used aiming at more accurate diagnoses in order to improve therapeutic approach. In this scenario, speckle tracking echocardiography (STE) uses natural myocardial markers to analyze the systolic deformation of the left ventricle (LV). OBJECTIVE: To measure the longitudinal transmural global strain (GS) of the LV through STE in patients with severe DCM, comparing the results with normal individuals and with echocardiographic parameters established for the analysis of LV systolic function, validating the method in this population. METHODS: We studied 71 patients with severe DCM (53 ± 12 years, 72% men) and 20 controls (30 ± 8 years, 45% men). We obtained LV volumes and ejection fraction by two and three-dimensional echocardiography, Doppler parameters, tissue Doppler and GS was obtained by STE. RESULTS: Compared to controls, LV volumes were higher in the DCM group; however, LVEF and peak velocity of E wave were lower in the latter. The myocardial performance index was higher among patients. Myocardial velocities at the tissue Doppler (S', e', a') were significantly lower and E/e' ratio was higher in the DCM group. The GS was decreased in the DCM group (-5.5% ± 2.3%) when compared to controls (-14.0% ± 1.8%). CONCLUSION: In this study, GS was significantly lower in patients with severe DCM, bringing new perspectives for therapeutic approaches in this specific population.

Assessment of right ventricular (RV) function is difficult due to the complex shape of this chamber. Tricuspid annular plane systolic excursion (TAPSE) measured with M-mode echocardiography is frequently used as an index of RV function. However, its accuracy may be limited by ultrasound beam misalignment. We hypothesized that two-dimensional (2D) speckle tracking echocardiography (STE) could provide more accurate estimates of RV function. Accordingly, STE was used to quantify tricuspid annular displacement (TAD), from which RV longitudinal shortening fraction (LSF) was calculated. These STE derived indices were compared side-by-side with M-mode TAPSE measurements against cardiac magnetic resonance (CMR) derived RV ejection fraction (EF).Echocardiography (Philips iE33, four-chamber view) and CMR (Siemens, 1.5 T) were performed on the same day in 63 patients with a wide range of RV EF (23-70% by CMR). TAPSE was measured using M-mode echocardiography. TAD and RV LSF were obtained using STE analysis (QLAB CMQ, Philips). TAPSE, TAD and RV LSF values were compared with RV EF obtained from CMR short axis stacks.STE analysis required15 seconds and was able to track tricuspid annular motion in all patients as verified visually. Correlation between RV EF and TAD (0.61 free-wall, 0.65 septal) was similar to that with M-mode TAPSE (0.63). However, STE-derived RV LSF showed a higher correlation with CMR EF (r = 0.78).RV LSF measurement by STE is fast and easy to obtain and provides more accurate evaluation of RV EF than the traditional M-mode TAPSE technique, when compared to CMR reference. (Echocardiography 2012;29:19-24).

Background Left ventricular (LV) volumes and ejection fraction derived from two-dimensional echocardiography are two measures of adverse LV remodeling, which predict survival in patients with systolic heart failure. However, the geometric assumptions and image foreshortening that can occur with two-dimensional echocardiography reduces measurement accuracy and thus predictive value. By its nature, three-dimensional (3D) echocardiography allows the entire LV shape to be studied, providing a methodology to examine LV remodeling through LV curvature on a global and regional scale. The aim of this study was to correlate changes in global and regional LV shape to LV ejection fraction. Methods Full-volume, 3D transthoracic echocardiographic studies of the left ventricle were performed in 106 consecutive patients with either normal left ventricles ( n = 59) or cardiomyopathies ( n = 47). Customized software (QLAB) was used to extract segmented 3D LV endocardial shells at end-systole and end-diastole and to analyze these shells to determine global and regional LV shape analysis. Independent t tests were used for intergroup comparisons, and linear regression was used to correlate regional shape changes with systolic performance. Results Derivation and analysis of the 3D LV shells was possible in all patients. Patients with dilated cardiomyopathy had significantly smaller curvature values, indicating rounder global LV shape throughout the cardiac cycle. Regional analysis identified a loss of septal and apical curvatures in these patients. Systolic apical mean curvature was well correlated with LV ejection fraction ( r = 0.89). Conclusions This is the first study to demonstrate that regional remodeling measured by regional 3D LV curvature correlates well with LV function. As well, this methodology is independent of the geometric assumptions that limit the predictive value of two-dimensional echocardiographic measures of LV remodeling. Overall, this is a novel tool that may have applications in the assessment and prediction of outcomes of different forms of dilated cardiomyopathy.

Seeing is believing. A dramatic evolution in medical imaging has occurred within the past half century. Echocardiography is no exception. The basic, physical nature of ultrasound as a wave propagation phenomenon was well understood for most of the twentieth century. However the ability to control the transmission and reception of sound waves with extraordinary precision has advanced significantly. This coupled with the ability to process, display and quantify enormous amounts of data has progressed echocardiography into modality that will change cardiac intervention. For decades, interpreting ultrasound images was the domain of highly specialized experts. Today, 3D transesophageal echocardiography (3D TEE) has generated near optical cardiac images. The realm of understanding cardiac mechanical motion in all of its spatial and temporal dimensions is elucidating hidden pearls of general physiologic insight for echocardiography as well as precise diagnoses for patients.

The recent development of 3-dimensional (3D) surface detection algorithm of the endocardial and epicardial surfaces from real-time 3D echocardiographic (RT3DE) datasets allows direct semiautomated quantification of left ventricular mass (LVM). Our aims were to (1) evaluate the accuracy of RT3DE measurements of LVM using this algorithm against cardiac magnetic resonance (CMR) reference and (2) compare RT3DE LVM with conventional M-mode, 2-dimensional (2D), and RT3DE-guided biplane measurements.A total of 205 patients were studied in 2 protocols: (1) RT3DE and CMR imaging was performed on the same day in 55 subjects; (2) in an additional 150 subjects, RT3DE, 2D, and M-mode images were acquired. In both protocols, RT3DE endocardial and epicardial surfaces were semiautomatically identified at end diastole (QLab, Philips Medical Systems, Andover, MA) to calculate LVM. CMR, 2D, and M-mode-derived LVM were obtained using standard techniques.A significant correlation (r = 0.95) was noted between RT3DE and CMR-derived LVM with a small bias of -2 g. M-mode-derived LVM measurements (175 +/- 64 g) were significantly larger than RT3DE LVM (123 +/- 39 g, bias: 52 g) with moderate correlation (r = 0.76). No significant differences in LVM were noted between 2D (125 +/- 42 g) and RT3DE values (bias: 1.2 g) with good correlation (r = 0.91, P.001). However, the best correlation was noted between RT3DE and RT3DE-guided biplane LVM values (r = 0.95, P.001, bias: -4.6 g). Intraobserver, interobserver variability, and test-retest variability of the RT3DE measurements were 9%, 12%, and 6%, respectively.RT3DE imaging using the 3D surface detection algorithm allows accurate and reproducible measurements of LVM. RT3DE-guided biplane technique can be used as an accurate time-saving alternative in clinical practice.

SummaryBackgroundRecent developments in 2D speckle tracking imaging allow not only measurements of regional myocardial strain, but also velocities of the mitral annulus. The aim of this study was to determine the accuracy of speckle tracking derived mitral annulus velocity compared with conventional pulsed wave Doppler measurements.Methods2D speckle tracking was acquired from the apical 4-chamber view (QLab, Speckle SQ, Philips, Andover, MA) in 169 subjects. While using texture tracking, two small regions of interest (ROIs) were placed in the septal (IVS) and lateral corners (LAT) of the mitral annulus. The software automatically tracked the ROIs frame-by-frame, yielding regional mean velocity curves of the mitral annulus throughout the cardiac cycle (synthetic pulsed wave Doppler; SPW). From these curves, peak systolic, early- and late-diastolic velocities of the mitral annulus (S′-SPW, E′-SPW, and A′-SPW) were measured. Peak systolic, early- and late-diastolic velocity in the mitral annulus (S′, E′, and A′) by conventional pulsed wave tissue Doppler tracing were also obtained.ResultsAdequate ROI tracking was observed in 150/169 subjects in IVS and 139/169 subjects in LAT of the mitral annulus. All annular velocities derived from SPW were significantly lower than corresponding velocities obtained from conventional method in both IVS and LAT regions of the mitral annulus. However, significant correlation between S′ (E′, A′)-SPW and S′ (E′, A′) was observed. In particular, a good correlation between E′-SPW and E′ was noted in both IVS (r=0.89, P26 for predicting E/E′ in IVS>15, sensitivity, specificity, and accuracy were 83%, 97%, and 94%, respectively. E/E′-SPW in LAT>13 had a 94% sensitivity, 92% specificity, and 93% accuracy for predicting E/E′ in LAT>10.ConclusionsThe values of annular velocities by SPW were significantly lower compared to those assessed by traditional tissue velocities. However, new cut-off values of E/E′-SPW for predicting elevated LV filling pressure highly correlated with traditional parameters. 2D speckle tracking imaging provides another strategy for evaluating LV filling pressures.

Aims Two-dimensional speckle tracking echocardiography (2DSTE) allows measurements of left ventricular (LV) volumes and LV ejection fraction (LVEF) without manual tracings. Our goal was to determine the accuracy of 2DSTE against real-time 3D echocardiography (RT3DE) and against cardiac magnetic resonance (CMR) imaging. Methods and results In Protocol 1, 2DSTE data in the apical four-chamber view (iE33, Philips) and CMR images (Philips 1.5T scanner) were obtained in 20 patients. The 2DSTE data were analysed using custom software, which automatically performed speckle tracking analysis throughout the cardiac cycle. LV volume curves were generated using the single-plane Simpson’s formula, from which end-diastolic volume (LVEDV), end-systolic volume (LVESV), and LVEF were calculated. In Protocol 2, the 2DSTE and RT3DE data were acquired in 181 subjects. RT3DE data sets were acquired, and LV volumes and LVEF were measured using QLab software (Philips). In Protocol 1, excellent correlations were noted between the methods for LVEDV (r ¼ 0.95), ESV (r ¼ 0.95), and LVEF (r ¼ 0.88). In Protocol 2, LV volume waveforms suitable for analysis were obtained from 2DSTE images in all subjects. The time required for analysis was ,2 min per patient. Excellent correlations were noted between the methods for LVEDV (r ¼ 0.95), ESV (r ¼ 0.97), and LVEF (r ¼ 0.92). However, 2DSTE significantly underestimated LVEDV, resulting in a mean of 8% underestimation in LVEF. Intra- and inter-observer variabilities of 2DSTE were 7 and 9% in LV volume and 6 and 8% in LVEF, respectively. Conclusions Two-dimensional speckle tracking echocardiography measurements resulted in a small but significant underestimation of LVEDV and EF compared with RT3DE. However, the accuracy, low intraand inter-observer variabilities and speed of analysis make 2DSTE a potentially useful modality for LV functional assessment in the routine clinical setting.

We present and validate image-based speckle-tracking calipers for quantification of tissue deformation and rotation in dynamic cardiovascular phantom models. Lagrangian strain was computed from the change in distance between caliper regions-of-interest (ROIs) positioned within the wall of a pulsatile phantom and compared with reference measurements derived from cardiac CT imaging. In a torsion phantom, rotational tissue excursion in a 2D plane was estimated and compared with reference values from CT-scan data. Tissue deformation and rotation measurements correlated well with their respective reference measurements. Our algorithm is capable of estimating strain and rotation from distinct tissue regions without requiring explicit cardiac border detection, a step which can be especially challenging in patients with poor acoustic windows.

Three-dimensional echocardiography has emerged as an essential tool for visualizing cardiac anatomy and for making more accurate measurements of cardiac structure and function. Recently, improvements in 3D beam-forming and transducer technologies have allowed higher resolution imaging from a transesophageal echocardiographic probe. This is creating new avenues for real-time visualization of intracardiac procedures without the need for cardiopulmonary bypass or opening the beating heart. Evolutions in visualization will allow a wider array of reparative procedures to be performed minimally invasively within a beating heart.

Our study goals were to evaluate the 3-dimensional matrix array transesophageal echocardiographic (3D-MTEE) probe by assessing the image quality of native valves and other intracardiac structures.Because 3-dimensional transesophageal echocardiography with gated rotational acquisition is not used routinely as the result of artifacts, lengthy acquisition, and processing, a 3D-MTEE probe was developed (Philips Medical Systems, Andover, Massachusetts).In 211 patients, 3D-MTEE zoom images of the mitral valve (MV), aortic valve, tricuspid valve, interatrial septum, and left atrial appendage were obtained, followed by a left ventricular wide-angled acquisition. Images were reviewed and graded off-line (Xcelera with QLAB software, Philips Medical Systems).Excellent visualization of the MV (85% to 91% for all scallops of both MV leaflets), interatrial septum (84%), left atrial appendage (86%), and left ventricle (77%) was observed. Native aortic and tricuspid valves were optimally visualized only in 18% and 11% of patients, respectively.The use of 3D-MTEE imaging, which is feasible in most patients, provides superb imaging of native MVs, which makes this modality an excellent choice for MV surgical planning and guidance of percutaneous interventions. Optimal aortic and tricuspid valve imaging will depend on further technological developments. Fast acquisition and immediate online display will facilitate wider acceptance and routine use in clinical practice.

This article addresses the current state of the art of technology in three-dimensional echocardiography as it applies to transducer design, beam forming, display, and quantification. Because three-dimensional echocardiography encompasses many technical and clinical areas, this article reviews its strengths and limitations and concludes with an analysis of what to use when.

Background The recent advent of real-time 3D ultrasound (3DUS) imaging enables a variety of new surgical procedures. These procedures are hampered by the difficulty of manipulating tissue guided by the distorted, low-resolution 3DUS images. To lessen the effects of these limitations, we investigated stereo displays and surgical robots for 3DUS-guided procedures. Methods By integrating real-time stereo rendering of 3DUS with the binocular display of a surgical robot, we compared stereo-displayed 3DUS with normally displayed 3DUS. To test the efficacy of stereo-displayed 3DUS, eight surgeons and eight non-surgeons performed in vitro tasks with the surgical robot. Results Error rates dropped by 50% with a stereo display. In addition, subjects completed tasks faster with the stereo-displayed 3DUS as compared to normal-displayed 3DUS. A 28% decrease in task time was seen across all subjects. Conclusions The results highlight the importance of using a stereo display. By reducing errors and increasing speed, it is an important enhancement to 3DUS-guided robotics procedures. Copyright © 2006 John Wiley & Sons, Ltd.

Although three-dimensional (3D) echocardiography is still in its evolution, cutting edge advances that allow quantifiable images of cardiac structures to be created in real-time will begin to increase its use drastically. One of the most promising uses of the technology is in the planning, optimization, and postoperative surveillance of mitral valve repair techniques and devices. This article reviews the development of 3D echocardiography and presents illustrations of how it may be applied to improving mitral valve repair techniques. It is conceivable in the near future that mitral repair procedures will be designed and customized for each patient preoperatively using data obtained from 3D echo images and computerized virtual surgery techniques. Such tools will allow the surgeon to design operations that thoroughly analyze valve geometry and stress distribution before ever entering the operating room.