An intensive interactive course for 3D echocardiography: is crop till you drop an effective learning strategy?

Transcription

1 European Journal of Echocardiography (2008) 9, doi: /j.euje An intensive interactive course for 3D echocardiography: is crop till you drop an effective learning strategy? Carly Jenkins 1, Mark Monaghan 2, Girish Shirali 3, Raj Guraraja 4, and Thomas H. Marwick 1 * 1 University of Queensland, Department of Medicine, Princess Alexandra Hospital, Ipswich Road, Brisbane, Q4102, Australia; 2 King s College Hospital, London, UK; 3 Children s Heart Program, Charleston, SC, USA; and 4 Philips Medical Systems, USA Received 13 March 2007; accepted after revision 2 June 2007; online publish-ahead-of-print 15 August 2007 KEYWORDS Three-dimensional echocardiography; Two-dimensional echocardiography Three-dimensional echocardiography (3DE) has recently become more accessible for clinical use because of the feasibility of live 3D acquisition. 1 This technique adds value to the standard 2D examination by improving quantitation for example, in the measurement of LV volumes, 2 6 and providing more effective visualization through the additional dimension 7 for example, in evaluation of mitral valve disease 8 and congenital abnormalities. 8,9 However, despite these potential benefits, the uptake of 3DE as a clinical tool has been slow. There are many potential reasons for this, including the cost and availability of * Corresponding author. Tel: þ ; fax: þ address: t.marwick@uq.edu.au (T.H. Marwick) Background Three-dimensional echocardiography (3DE) appears to show incremental benefit over twodimensional echocardiography (2DE), but it s uptake has been slow. We tested attendees before and after an intensive interactive training course to identify its efficacy. Methods Attendees (n ¼ 35, 23 cardiologists, 12 sonographers) were shown how to use 3DE review software and asked to identify the pathology of five patients (wall motion abnormality, peri-prosthetic mitral regurgitation, subaortic membrane, small ventricular septal defect, submitral stenosis) on 2D and 3D images. In the following one and a half-day interactive teaching course, brief presentations on application of 3DE for assessment of wall motion, valve and congenital abnormalities were followed by review of 3D datasets, during which the attendees made their own interpretations before being shown the optimal viewing strategy. Test cases were not discussed and the test was repeated at the end of the course. Results Most attendees (57%) had access but with little or no use of a 3DE system. Three-dimensional echocardiography had no incremental value before training. After training, overall correct responses significantly improved compared with baseline interpretation, although improvement was not the same for all diagnoses. All groups (cardiologists vs. sonographers, inexperienced vs. moderately experienced reviewers) improved similarly. Conclusions Incorporation of 3DE into standard practice may be limited by inexperience. An interactive teaching course with rehearsal and direct mentoring appears to overcome this limitation and may improve the uptake of this technique. new equipment, but one that could be easily rectified is unfamiliarity with the new technology. We therefore sought to test attendees before and after a brief interactive training course in order to define its efficacy. Methods Study design Attendees (n ¼ 35) at a 3DE training course were shown how to use 3D review software and asked to identify the pathology on 2D and 3D images of five patients (wall motion abnormality, periprosthetic mitral regurgitation, subaortic membrane, small ventricular septal defect, submitral stenosis). In a one and a half-day interactive teaching course, brief presentations on application of 3DE for Published on behalf of the European Society of Cardiology. All rights reserved. & The Author For permissions please journals.permissions@oxfordjournals.org.

2 374 C. Jenkins et al. assessment of wall motion, valve and congenital abnormalities were followed by more than 50 different 3D datasets from three different hospitals, on which the attendees made their own interpretations before being shown the optimal viewing strategy. The test cases were not discussed in the course. Finally, a second test was performed, involving 3D analysis of the same five baseline test cases after 3D training. Image acquisition Two- and three-dimensional echocardiographic images were obtained for both the test and training cases. An experienced sonographer acquired standard 2D echocardiographic views using harmonic imaging with a transthoracic 3 MHz phased array transducer (ie33, Philips Medical Systems, Andover, MA). Images were stored in digital format and then the most relevant were selected for viewing; 3DE were obtained in the same manner as 2DE. Live (one cardiac cycle) and full volume without colour (over four cardiac cycles) and with colour (over eight cardiac cycles) 3DE images (Figure 1A) were also gathered using a matrix array transducer (4 transducer, Philips ie33 system). Three-dimensional echocardigraphs were reviewed using commercially available software (QLab 4.2, Philips Medical Systems, Andover, MA) (Figure 1B). Case 1: prosthetic mitral regurgitation In this patient with a mitral valve replacement, 2DE showed significant mitral regurgitation with one valvular and one peri-valvular regurgitant jet (Figure 2A). In an apical colour full volume 3DE, Figure 1 (A) Live 3DE (right panel), colour full volume (centre panel) and full volume (right panel); 3DE imaging. (B) Three-dimensional echocardiography cropping and reviewing software; QLab 4.2, Philips Medical Systems.

3 Interactive course for 3D echo 375 Figure 2 (A) Prosthetic mitral regurgitation 2DE images. Apical four chamber with colour showing mitral regurgitation (left panel). Zoomed image of the mitral valve from the apical four chamber view (centre panel). Parasternal long axis view with colour showing mitral regurgitation (right panel). (B) Uncropped colour full volume acquisition (left panel); 3DE imaging. Cropped colour 3DE viewing from left atrium into left ventricle, green arrows show peri-valvular mitral regurgitation and red arrow showing valvular regurgitation (right panel). viewing the mitral valve through the left atrium showed three perivalvular jets and one valvular jet of mitral regurgitation (Figure 2B). Case 2: wall motion abnormality In this stress echocardiogram, five views and one full volume 3DE were taken before and immediately after exercise. Foreshortening of the apex at peak stress prevented the detection of wall motion abnormalities (Figure 3A), but use of 3DE to open up the apex demonstrated an apical wall motion abnormality at peak stress (Figure 3B). Case 3: ventricular septal defect Increased pulmonary flowwas detected on 2DE, with no cause identified (Figure 4A). Cropping into the 3DE acquisition from a parasternal long axis-equivalent view revealed a small membranous VSD (Figure 4B). Case 4: left ventricular outflow tract mass Two-dimensional echocardiography showed a large echogenic mass in the left ventricular outflow tract. The nature of the mass was unclear and the point of attachment could not be shown (Figure 5A). Cropping from an apical long axis-equivalent plane into 3DE acquisition showed the point of attachment to be in the intra-ventricular septum (Figure 5B). Case 5: subvalvular mitral stenosis Despite an increased Doppler gradient (10 mmhg) across the mitral valve, grey scale 2DE showed the valve to open well (Figure 6B). On the full volume 3DE, cropping from the parasternal long axis equivalent view showed the increased Doppler gradient to arise from the thickened chordae and not the valve itself (Figure 6B).

4 376 C. Jenkins et al. Figure 3 (A) Stress echocardiogram 2DE apical four chamber (top panels) and two chamber (bottom panels) views with rest (left panels) and stress (right panels) images. Green arrows show apical foreshortening on peak imaging. (B) Views of 3DE imaging of rest full volume (left panel) and peak full volume (right panel). Using the 3DE cropping tool and elongating the left ventricle, an apical wall motion abnormality is shown (green arrow). Statistical analysis Results are represented as percentage of correct answers, with comparisons using the chi-square test a P value of,0.05 was considered to be significant. 10,11 Data analyses were performed using SPSS statistical software (SPSS v10, Chicago, IL). Results Course attendees Of the attendees (n ¼ 35), 23 were cardiologists and 12 sonographers, from both adult and paediatric backgrounds. Most attendees had access to a 3DE system before the course, but had used it little or not at all (n ¼ 57%). Incremental value of 3DE Table 1 shows that 3DE had little incremental value on baseline testing. After training, the overall number of correct responses significantly improved compared with baseline 2DE and 3DE interpretations. All groups (cardiologists vs. sonographers, inexperienced vs. moderately experienced reviewers) improved similarly (Figure 7).

5 Interactive course for 3D echo 377 Figure 4 (A) Colour 2DE images from a zoomed parasternal long axis view (left panel), zoomed parasternal short axis view of the aortic valve and a subcostal four chamber view. (B) Images of 3DE from the parasternal long axis view using live imaging (left panel) and colour full volume (right panel). Green arrows show membranous ventricular septal defect. IVS intra-ventricular septum; Ao aorta; AV aortic valve; RV right ventricle; LV left ventricle; LVOT left ventricle outflow tract. Improvement was not the same for all diagnoses (Table 1). The recognition of apical wall motion abnormality from the 3DE (case study 2), recognition of the membranous VSD and recognition of subvalvular mitral stenosis improved after training. However, assessment of the number of regurgitant jets in the case of prosthetic mitral regurgitation and recognition of the subaortic membrane did not significantly improve from pre- to post-3de. Discussion The introduction of new technology mandates the acquisition of new skills, and the learning curve needed to apply 3DE viewing and cropping techniques is so far undefined. The results of this study indicate that a shortcourseincludingdirectinteractionwith3ddatasets can improve the interpretation of complicated echocardiograms. Defining the learning curve in echocardiography Current training guidelines propose various numbers of reviewed studies for different levels of echocardiographic training, based on expert opinion. 12 A limited literature shows that short courses and other training strategies are of value for teaching the requisite skills to noncardiologists. 13,14 The strongest evidence base for defining the learning curve is for stress echocardiography. 15 Current guidelines do not address the training required to use new technologies such as 3DE, but they do acknowledge that there is a certain procedure-specific learning curve for advanced studies. They also suggest that special procedures are best learnt under a qualified expert and that performing and interpreting a certain number of cases is required to reach certain levels in training. 16 Limitations Although workstations were provided for attendees to interact with the datasets, the circumstances of reviewing the case studies in a classroom setting do not correspond to real life. In the interests of time, the studies were shown in the course of an hour, necessitating significant editing to a handful of clips. Review of a complete study under more usual circumstances might have improved accuracy, which (although improved) was still suboptimal at the end

6 378 C. Jenkins et al. Figure 5 (A) Grey scale and colour 2DE images from a zoomed apical long axis views (left panel), zoomed apical five chamber colour view of the aortic valve (right panel). Green arrow shows the LVOT mass and colour Doppler showing flow acceleration. (B) Images of 3DE showing LVOT (blue arrow) echo density point of attachment (green arrow) noted to be on the septum (subaortic membrane red arrow). Ao aorta; LV left ventricle; LA left atrium; LVOT left ventricle outflow tract. of the course. This increment in accuracy of 3D interpretation might be further improved by a longer or more intensive training course. Alternative study designs to define the efficacy of the course were considered, for example, application of the test to independent groups at baseline and after training. However, the use of the same test cases has the advantage of permitting paired comparisons, and we sought to minimize bias based on earlier viewing of the cases by not discussing them during the course. Conclusions The incorporation of 3DE into the standard practice of clinical laboratories has been slow, and may be limited by inexperience. An interactive teaching course with rehearsal

7 Interactive course for 3D echo 379 Figure 6 (A) Zoomed 2DE image of mitral valve from the parasternal long axis window (left panel). A four chamber colour image showing a Doppler gradient across (green arrow) the mitral valve (centre panel). Parasternal short axis view of the mitral valve opening in systole (right panel). LV left ventricle; LA left atrium; MV mitral valve. (B) Parasternal 3DE images showing mitral chordae thickening and normal mitral valve area (1.8 cm 2 ). Table 1 Percentage of correct answers with correlations between interpretations for case studies pre-2de, pre- and post-3de Overall Prosthetic MR Wall motion VSD LVOT mass Submitral stenosis Pre-2DE interpretation (%) Pre-3DE interpretation (%) Post-3DE interpretation (%) Pre-2DE vs. pre-3de (P values) Pre-2DE vs. post-3de (P values) Pre-3DE vs. post-3de (P values)

8 380 C. Jenkins et al. Figure 7 Percentages of correct answers and comparisons between groups: pre-2de (purple), pre-3de (green) and post-3de (blue) (cardiologists vs. sonographers, inexperienced vs. moderately experienced reviewers). and direct mentoring appears to overcome this limitation and may improve the uptake of this technique. Supplementary material Supplementary data associated with this article can be found, in the online version, at doi: / j.euje References 1. Xie MX, Wang XF, Cheng TO, Lu Q, Yuan L, Liu X. Real-time 3-dimensional echocardiography: a review of the development of the technology and its clinical application. Prog Cardiovasc Dis 2005;48: Jacobs LD, Salgo IS, Goonewardena S, Weinert L, Coon P, Bardo D et al. Rapid online quantification of left ventricular volume from real-time three-dimensional echocardiographic data. Eur Heart J 2006;27: Jenkins C, Bricknell K, Hanekom L, Marwick TH. Reproducibility and accuracy of echocardiographic measurements of left ventricular parameters using real-time three-dimensional echocardiography. J Am Coll Cardiol 2004;44: Jenkins C, Chan J, Hanekom L, Marwick TH. Accuracy and feasibility of online 3-dimensional echocardiography for measurement of left ventricular parameters. J Am Soc Echocardiogr 2006;19: Corsi C, Lang RM, Veronesi F, Weinert L, Caiani EG, MacEneaney P et al. Volumetric quantification of global and regional left ventricular function from real-time three-dimensional echocardiographic images. Circulation 2005;112: Heusch A, Koch JA, Krogmann ON, Korbmacher B, Bourgeois M. Volumetric analysis of the right and left ventricle in a porcine heart model: comparison of three-dimensional echocardiography, magnetic resonance imaging and angiocardiography. Eur J Ultrasound 1999;9: Lang RM, Mor-Avi V, Sugeng L, Nieman PS, Sahn DJ. Three-dimensional echocardiography: the benefits of the additional dimension. J Am Coll Cardiol 2006;48: Delabays A, Jeanrenaud X, Chassot PG, Von Segesser LK, Kappenberger L. Localization and quantification of mitral valve prolapse using threedimensional echocardiography. Eur J Echocardiogr 2004;5: van den Bosch AE, Ten Harkel DJ, McGhie JS, Roos-Hesselink JW, Simoons ML, Bogers AJ et al. Characterization of atrial septal defect assessed by real-time 3-dimensional echocardiography. J Am Soc Echocardiogr 2006;19: Bland JM, Altman DG. Calculating correlation coefficients with repeated observations: Part 2 correlation between subjects. BMJ 1995; 310: Bland JM, Altman DG. Calculating correlation coefficients with repeated observations: Part 1 correlation within subjects. BMJ 1995;310: Beller GA, Bonow RO, Fuster V. ACC revised recommendations for training in adult cardiovascular medicine. Core cardiology training II (COCATS 2) (Revision of the 1995 COCATS training statement). J Am Coll Cardiol 2002;39: Ellis D. Handheld echocardiography core skill for emergency physicians or another expensive course? Emerg Med J 2006;23: Glas KE. Training in perioperative echocardiography. Curr Opin Anaesthesiol 2006;19: Picano E, Lattanzi F, Orlandini A, Marini C, L Abbate A. Stress echocardiography and the human factor: the importance of being expert. J Am Coll Cardiol 1991;17: Stewart WJ, Aurigemma GP, Bierman FZ, Gardin JM, Kisslo JA, Pearlman AS et al. Task Force 4: Training in Echocardiography.