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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 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.

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

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.

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