Abstract
2603
Objectives Our institution practice a two day stress-first protocol for myocardial perfusion imaging (MPI) where only equivocal or abnormal stress studies are followed up by rest imaging. This approach helps to reduce unnecessary radiation exposure for patients and decreases overall cost. In the last few years technologists have noticed an increased referral for rest imaging studies. It was hypothesised that junior physicians were more likely to refer patients for rest imaging. Therefore our aim was to evaluate the trend in patients referred for rest imaging. The aim was to assess whether junior physicians are more likely to refer patients for rest imaging and need more training.
Methods A retrospective analysis of patients from 2008 to 2015 referred for SPECT MPI was undertaken. We examined the frequency of patients who were referred for a follow-up rest imaging study. MPIs are performed without attenuation correction in our institution.
Results 6,334 patients were referred in the period from 2008 to 2015 and 2,986 (46.5%; range per year 34.9-53.6%) were brought back for rest imaging. The number of patients referred for MPI has increased markedly and almost doubled since 2011 (2011: 570; 2015: 1131). Both consultants and junior physicians experienced over time a growing need for more rest imaging studies (Total 2008: 34.9 % to 2015: 53.6%, p<0.001). The increase in patients and need for more rest studies indicated a change in referrals for MPI and might represent a change in prevalence of ischemic heart disease in the patients. In the last year it turned out that it was the specialists who required more rest scans compared with junior physicians (2015: 56.5 % vs. 50.0% (p=0.03). Junior physicians showed large variations in the usage of rest imaging (range: 22.2-72.8%) compared to specialists (range: 38.6-51.7%). The observer dependency seen in our data could be reduced by use of attenuation correction.
Conclusions The number of patients referred for MPI and the fraction who need rest imaging has increased significantly from 2008 to 2015. This may represent a changed practice in the usage of MPI as diagnostic tool in the evaluation of ischemic heart disease. Interestingly, physicians under training perform a slightly lower fraction of patients for rest imaging studies. However, a huge variation in usage of rest imaging among young physicians indicate that more training is needed.