Image quality to estimate ventricular ejection fraction by last year medical students improves after short courses of training

Abstract

Background: Transthoracic echocardiography is the primary imaging modality for diagnosing cardiac conditions but medical education in this field is limited. We tested the hypothesis that a structured theoretical and supervised practical course of training in focused echocardiography in last year medical students results in a more accurate assessment and more precise calculation of left ventricular ejection fraction after ten patient examinations. Methods: After a theoretical introduction course 25 last year medical students performed ten transthoracic echocardiographic examination blocks in postsurgical patients. Left ventricular function was evaluated both with an eye-balling method and with the calculated ejection fraction using diameter and area of left ventricles. Each examination block was controlled by a certified and blinded tutor. Bias and precision of measurements were assessed with Bland and Altman method. Results: Using the eye-balling method students agreed with the tutor’s findings both at the beginning (88%) but more at the end of the course (95.7%). The variation between student and tutor for calculation of area, diameter and ejection fraction, respectively, was significantly lower in examination block 10 than in examination block 1 (each p < 0.001). Students underestimated both the length and the area of the left ventricle at the outset, as complete imaging of the left heart in the ultrasound sector was initially unsuccessful. Conclusions: A structured theoretical and practical transthoracic echocardiography course of training for last year medical students provides a clear and measurable learning experience in assessing and measuring left ventricular function. At least 14 examination blocks are necessary to achieve 90% agreement of correct determination of the ejection fraction.