Publications

BACKGROUND: Proficiency in transthoracic echocardiography (TTE) requires an integration of cognitive knowledge and psychomotor skills. Whereas cognitive knowledge can be quantified, psychomotor skills are implied after repetitive task performance. We applied motion analyses to evaluate psychomotor skill acquisition during simulator-based TTE training.

METHODS AND RESULTS: During the first month of their fellowship training, 16 cardiology fellows underwent a multimodal TTE training program for 4 weeks (8 sessions). The program consisted of online and live didactics as well as simulator training. Kinematic metrics (path length, time, probe accelerations) were obtained at the start and end of the course for 8 standard TTE views using a simulator. At the end of the course TTE image acquisition skills were tested on human models. After completion of the training program the trainees reported improved self-perceived comfort with TTE imaging. There was also an increase of 8.7% in post-test knowledge scores. There was a reduction in the number of probe accelerations [median decrease 49.5, 95% CI = 29-73, adjusted P < 0.01], total time [median decrease 10.6 s, 95% CI = 6.6-15.5, adjusted P < 0.01] and path length [median decrease 8.8 cm, 95% CI = 2.2-17.7, adjusted P < 0.01] from the start to the end of the course. During evaluation on human models, the trainees were able to obtain all the required TTE views without instructor assistance.

CONCLUSION: Simulator-derived motion analyses can be used to objectively quantify acquisition of psychomotor skills during TTE training. Such an approach could be used to assess readiness for clinical practice of TTE.

OBJECTIVES: Contrary to the rest of the mitral annulus, inter-trigonal distance is known to be relatively less dynamic during the cardiac cycle. Therefore, intertrigonal distance is considered a suitable benchmark for annuloplasty ring sizing during mitral valve (MV) surgery. The entire mitral annulus dilates and flattens in patients with ischemic mitral regurgitation (IMR). It is assumed that the fibrous trigone of the heart and the intertrigonal distance does not dilate. In this study, we sought to demonstrate the changes in mitral annular geometry in patients with IMR and specifically analyze the changes in intertrigonal distance during the cardiac cycle.

METHODS: Intraoperative three-dimensional transesophageal echocardiographic data obtained from 26 patients with normal MVs undergoing nonvalvular cardiac surgery and 36 patients with IMR undergoing valve repair were dynamically analyzed using Philips Qlab ® software.

RESULTS: Overall, regurgitant valves were larger in area and less dynamic than normal valves. Both normal and regurgitant groups displayed a significant change in annular area (AA) during the cardiac cycle (P < 0.01 and P < 0.05, respectively). Anteroposterior and anterolateral-posteromedial diameters and inter-trigonal distance increased through systole (P < 0.05 for all) in accordance with the AAs in both groups. However, inter-trigonal distance showed the least percentage change across the cardiac cycle and its reduced dynamism was validated in both cohorts (P > 0.05).

CONCLUSIONS: Annular dimensions in regurgitant valves are dynamic and can be measured feasibly and accurately using echocardiography. The echocardiographically identified inter-trigonal distance does not change significantly during the cardiac cycle.

BACKGROUND: Traditional two-dimensional (2D) echocardiographic evaluation of tricuspid annulus (TA) dilation is based on single-frame measurements of the septolateral (S-L) dimension. This may not represent either the axis or the extent of dynamism through the entire cardiac cycle. In this study, we used real-time 3D transesophageal echocardiography (TEE) to analyze geometric changes in multiple axes of the TA throughout the cardiac cycle in patients without right ventricular abnormalities.

MATERIALS AND METHODS: R-wave-gated 3D TEE images of the TA were acquired in 39 patients undergoing cardiovascular surgery. The patients with abnormal right ventricular/tricuspid structure or function were excluded from the study. For each patient, eight points along the TA were traced in the 3D dataset and used to reconstruct the TA at four stages of the cardiac cycle (end- and mid-systole, end- and mid-diastole). Statistical analyses were applied to determine whether TA area, perimeter, axes, and planarity changed significantly over each stage of the cardiac cycle.

RESULTS: TA area (P = 0.012) and perimeter (P = 0.024) both changed significantly over the cardiac cycle. Of all the axes, only the posterolateral-anteroseptal demonstrated significant dynamism (P < 0.001). There was also a significant displacement in the vertical axis between the points and the regression plane in end-systole (P < 0.001), mid-diastole (P = 0.014), and mid-systole (P < 0.001).

CONCLUSIONS: The TA demonstrates selective dynamism over the cardiac cycle, and its axis of maximal dynamism is different from the axis (S-L) that is routinely measured with 2D TEE.

OBJECTIVE: To evaluate the feasibility of obtaining hemodynamic metrics of echocardiographically derived 3-dimensional printed mitral valve models deployed in a pulse-duplicator chamber.

DESIGN: Exploratory study.

SETTING: Tertiary-care university hospital.

PARTICIPANTS: Percutaneous MitraClip procedure patient.

INTERVENTIONS: Three-dimensional R-wave gated, full-volume transesophageal echocardiography images were obtained after deployment of the MitraClip device. A high-quality diastolic frame of the mitral valve was segmented using Mimics Innovation Suite and merged with a flange. The data were exported as a stereolithography (.stl) file, and a rigid 3-dimensional model was printed using a MakerBot Replicator 2 printer. A flexible silicone cast then was created and deployed in the pulse-duplicator chamber filled with a blood-mimicking fluid.

MEASUREMENTS AND MAIN RESULTS: The authors were able to obtain continuous-wave Doppler tracings of the valve inflow with a transesophageal echocardiography transducer. They also were able to generate diastolic ventricular and atrial pressure tracings. Pressure half-time and mitral valve area were computed from these measurements.

CONCLUSION: This pulse duplicator shows promising applications in hemodynamic testing of patient-specific anatomy. Future modifications to the system may allow for visualization and data collection of gradients across the aortic valve.

Three-dimensional (3D) printing is a rapidly evolving technology with several potential applications in the diagnosis and management of cardiac disease. Recently, 3D printing (i.e. rapid prototyping) derived from 3D transesophageal echocardiography (TEE) has become possible. Due to the multiple steps involved and the specific equipment required for each step, it might be difficult to start implementing echocardiography-derived 3D printing in a clinical setting. In this review, we provide an overview of this process, including its logistics and organization of tools and materials, 3D TEE image acquisition strategies, data export, format conversion, segmentation, and printing. Generation of patient-specific models of cardiac anatomy from echocardiographic data is a feasible, practical application of 3D printing technology.

BACKGROUND: Proficiency in transthoracic echocardiography (TTE) requires an integration of cognitive knowledge and psychomotor skills. Whereas cognitive knowledge can be quantified, psychomotor skills are implied after repetitive task performance. We applied motion analyses to evaluate psychomotor skill acquisition during simulator-based TTE training.

METHODS AND RESULTS: During the first month of their fellowship training, 16 cardiology fellows underwent a multimodal TTE training program for 4 weeks (8 sessions). The program consisted of online and live didactics as well as simulator training. Kinematic metrics (path length, time, probe accelerations) were obtained at the start and end of the course for 8 standard TTE views using a simulator. At the end of the course TTE image acquisition skills were tested on human models. After completion of the training program the trainees reported improved self-perceived comfort with TTE imaging. There was also an increase of 8.7% in post-test knowledge scores. There was a reduction in the number of probe accelerations [median decrease 49.5, 95% CI = 29-73, adjusted P < 0.01], total time [median decrease 10.6 s, 95% CI = 6.6-15.5, adjusted P < 0.01] and path length [median decrease 8.8 cm, 95% CI = 2.2-17.7, adjusted P < 0.01] from the start to the end of the course. During evaluation on human models, the trainees were able to obtain all the required TTE views without instructor assistance.

CONCLUSION: Simulator-derived motion analyses can be used to objectively quantify acquisition of psychomotor skills during TTE training. Such an approach could be used to assess readiness for clinical practice of TTE.

Despite the high impact of lapses in communication skills on patient care, these skills are often not explicitly taught in residency training programs. We implemented a simulation and web-based curriculum in communication for anesthesia residents and used a patient survey adapted from the Four Habits Coding Scheme to detect changes in patient feedback on residents' communication skills after the curricular intervention. Postintervention mean ratings of residents for the overall survey were higher than preintervention mean ratings. Future research will focus on assessing the curriculum's effectiveness and exploring the generalizability of the survey and curriculum.