Self-guided teaching designed to strengthen the ability to more precisely estimate left ventricular ejection fraction (LVEF) led to decreased interobserver variability (IOV) and more accurate EF measurements among a group of sonographers and cardiologists. These findings were published online Aug. 30 in the Journal of the American Society of Echocardiography.
The societies of echocardiography in the U.S. and Europe recommend visual estimation of EF as a way to confirm quantitative EF, though it is not suggested for use in isolation.
“[I]nterobserver variability for EF estimation has been reported to be as high as 14 percent,” wrote the study researchers, led by Paaladinesh Thavendiranathan, MD, of the Cleveland Clinic in Cleveland. “The aim of this study was to determine whether self-directed education could improve the accuracy and interobserver variability of visual estimation of EF and whether a multireader estimate improves measurement precision.”
A group of 31 full-time staff members—11 sonographers and 20 cardiologists—who performed an average of 8 to 10 echocardiographic studies daily and provided reports that included LVEF estimation participated in the study. They each gave single-point EF estimates for 30 echocardiograms in patients who underwent cardiac magnetic resonance (CMR) within 48 hours.
The group then got together for a one-hour session and discussed the 10 cases with the most variability among the readers. During the educational session, there was a review of the cases and a discussion about the discrepancies and how to improve accuracy and lower IOV.
After the session, the participants received the 30 original cases and asked for another set of readings within two weeks to confirm review. A month later, the participants received 20 new cases that were similar in pathology and EF range as the previous set.
At the start of the study, IOV was ±0.120, and after the education session it improved to ±0.97. EF misclassification, which the authors defined as ±0.05 of CMR EF decreased from 56 percent to 47 percent. The intervention especially benefitted the readers who were the least accurate at the outset. Additionally, the analysis revealed more precise EF when sonographers and cardiologists both made estimates.
While quality control programs may be logistically challenging for some facilities, the authors argued that a self-directed intervention such as the one in their study is quite feasible.
“Although we found only modest improvements in IOV and accuracy, the process of continuous quality improvement that was used in this study is transportable to other practices, where outcomes may be different, “ they wrote.