Publications

BACKGROUND: Transesophageal echocardiography (TEE) is a complex endeavor involving both motor and cognitive skills. Current training requires extended time in the clinical setting. Application of an integrated approach for TEE training including simulation could facilitate acquisition of skills and knowledge.

METHODS: Echo-naive nonattending anesthesia physicians were offered Web-based echo didactics and biweekly hands-on sessions with a TEE simulator for 4 weeks. Manual skills were assessed weekly with kinematic analysis of TEE probe motion and compared with that of experts. Simulator-acquired skills were assessed clinically with the performance of intraoperative TEE examinations after training. Data were presented as median (interquartile range).

RESULTS: The manual skills of 18 trainees were evaluated with kinematic analysis. Peak movements and path length were found to be independent predictors of proficiency (P < 0.01) by multiple regression analysis. Week 1 trainees had longer path length (637 mm [312 to 1,210]) than that of experts (349 mm [179 to 516]); P < 0.01. Week 1 trainees also had more peak movements (17 [9 to 29]) than that of experts (8 [2 to 12]); P < 0.01. Skills acquired from simulator training were assessed clinically with eight additional trainees during intraoperative TEE examinations. Compared with the experts, novice trainees required more time (199 s [193 to 208] vs. 87 s [83 to 16]; P = 0.002) and performed more transitions throughout the examination (43 [36 to 53] vs. 21 [20 to 23]; P = 0.004).

CONCLUSIONS: A simulation-based TEE curriculum can teach knowledge and technical skills to echo-naive learners. Kinematic measures can objectively evaluate the progression of manual TEE skills.

OBJECTIVES: Web and simulation technology may help in creating a transesophageal echocardiography (TEE) curriculum. The authors discuss the educational principles applied to developing and implementing a multimodal TEE curriculum.

DESIGN AND SETTING: The authors modified a pilot course based on principles for effective simulation-based education. Key curricular elements were consistent with principles for effective simulation-based education: (1) clear goals and carefully structured objectives, (2) conveniently accessed, graduated, longitudinal instruction, (3) a protected and optimal learning environment, (4) repetition of concepts and technical skills, (5) progressive expectations for understanding and skill development, (6) introduction of abnormalities after understanding of normal anatomy and probe manipulation is achieved, (7) live learning sessions that are customizable to meet learner needs and individualized proctoring in skill sessions, (8) use of multiple approaches to teaching, (9) regular and relevant feedback, and (10) application of performance and compliance measures.

PARTICIPANTS: Fifty-five learners participated in a curriculum with web-based modules, live teaching, and simulation practice between August 2011 and May 2013.

CONCLUSION: It is possible to develop and implement an integrated, multimodal TEE curriculum supported by educational theory. The authors will explore the transferability of this approach to intraoperative TEE on live patients.

PURPOSE: The purpose of this review was to evaluate new computer software available for 3-dimensional right ventricular (RV) volume estimation.

DESCRIPTION: Based on 2-dimensional echocardiography, various algorithms have been used for RV volume estimation. These are complex, time-consuming techniques and are prone to significant error. The current clinical paradigm of RV volume assessment is based on the visual quantitative assessment of chamber size and the use of tricuspid annular and RV internal diameters as a surrogate measure of RV volume. Hence, there is a need for a practical method for the intraoperative assessment of RV volume.

EVALUATION: The evaluation consists of an objective review of the capabilities of this software and its potential application in the operating room. The authors also performed a detailed review of the potential limitations and possible improvements.

CONCLUSIONS: This new software has the potential to be incorporated into the existing workflow environment of the ultrasound systems in the future, making it clinically feasible to perform perioperative RV volume analysis.

While percutaneous intervention is an alternative for patients who are not surgical candidates, the rate of morbidity and mortality is comparable to open repair. Appending the reported complications associated with percutaneous intervention (device mal-positioning, dislodgement, and entrapment in the sub-valvular apparatus), we report mechanical damage to the tricuspid valve (TV). Percutaneous closure with an Amplatzer septal occluder device was attempted on three patients who developed a ventricular septal defects (VSD) after myocardial infarction. In all three cases, damage to the tricuspid leaflet was noted post-procedure. The accompanying severe tricuspid regurgitation led to right ventricular failure, even in the patients where the VSD was considered successfully occluded. Despite successful deployment of the Amplatzer device, complications with catheter manipulation may still arise. Damage to the TV can occur during percutaneous VSD closure with Amplatzer device. Periprocedure TEE monitoring can detect damage to the tricuspid leaflets.

BACKGROUND: Mitral valve (MV) annular dynamics have been well described in animal models of functional mitral regurgitation (FMR). Despite this, little if any data exist regarding the dynamic MV annular geometry in humans with FMR. In the current study we hypothesized that 3-dimensional (3D) echocardiography, in conjunction with commercially available software, could be used to quantify the dynamic changes in MV annular geometry associated with FMR.

METHODS: Intraoperative 3D transesophageal echocardiographic data obtained from 34 patients with FMR and 15 controls undergoing cardiac operations were dynamically analyzed for differences in mitral annular geometry with TomTec 4D MV Assessment 2.0 software (TomTec Imaging Systems GmbH, Munich, Germany).

RESULTS: In patients with FMR, the mean mitral annular area (14.6 cm(2) versus 9.6 cm(2)), circumference (14.1 cm versus 11.4 cm), anteroposterior (4.0 cm versus 3.0 cm) and anterolateral-posteromedial (4.3 cm versus 3.6 cm) diameters, tenting volume (6.2 mm(3) versus 3.5 mm(3)) and nonplanarity angle (NPA) (154 degrees ± 15 versus 136 degrees ± 11) were greater at all points during systole compared with controls (p < 0.01). Vertical mitral annular displacement (5.8 mm versus 8.3 mm) was reduced in FMR compared with controls (p < 0.01).

CONCLUSIONS: There are significant differences in dynamic mitral annular geometry between patients with FMR and those without. We were able to analyze these changes in a clinically feasible fashion. Ready availability of this information has the potential to aid comprehensive quantification of mitral annular function and possibly assist in both clinical decision making and annuloplasty ring selection.

BACKGROUND: Owing to its elliptical shape, the left ventricle outflow tract (LVOT) area is underestimated by two-dimensional (2D) diameter-based calculations which assume a circular shape. This results in overestimation of aortic stenosis (AS) by the continuity equation. In cases of moderate to severe AS, this overestimation can affect intraoperative clinical decision making (expectant management versus replacement). The purpose of this intraoperative study was to compare the aortic valve area calculated by 2D diameter based and three-dimensional (3D) derived LVOT area via transesophageal echocardiography (TEE) and its impact on severity of AS.

METHODS: The LVOT area was calculated using intraoperative 2D and 3D TEE data from patients undergoing aortic valve replacement (AVR) and coronary artery bypass graft (CABG) surgery using the 2D diameter (RADIUS), 3D planimetry (PLANE), and 3D biplane (π·x·y) measurement (ELLIPSE) methods. For each method, the LVOT area was used to determine the aortic valve area by the continuity equation and the severity of AS categorized as mild, moderate, or severe.

RESULTS: A total of 66 patients completed the study. The RADIUS method (3.5 ± 0.9 cm(2)) underestimated LVOT area by 21% (p < 0.05) compared with the PLANE method (4.1 ± 0.1 cm(2)) and by 18% (p < 0.05) compared with the ELLIPSE method (4.0 ± 0.9 cm(2)). There was no significant difference between the two 3D methods, namely, PLANE and ELLIPSE. Seven AVR patients (18%) and 1 CABG surgery patient (6%) who had originally been classified as severe AS by the 2D method were reclassified as moderate AS by the 3D methods (p < 0.001).

CONCLUSIONS: Three-dimensional echocardiography has the potential to impact surgical decision making in cases of moderate to severe AS.