Aims: The administration of echocardiographic contrast agents has been shown to improve accuracy and be cost-effective in patients with suboptimal endocardial definition. We sought to investigate the implementation of contrast agents in clinical practice.
Methods and results: An electronic questionnaire was devised to determine the use of contrast ultrasound agents in clinical practice and sent electronically to echocardiography departments at each national health service hospital within the UK. Out of 198, 107 departments responded (54%). Out of 673,121 echocardiograms, 25,834 (3.8%) were performed with contrast. Out of 551 echocardiography machines, 358 (65%) were suitable for contrast use. Of the sonographers, out of 711, 112 (15.8%) could perform i.v. cannulation and 42 (5.9%) could administer contrast independently. The median time for an echocardiographic examination was 30 min (inter-quartile range 30-45 min). Significant predictors of contrast use were the presence of a consultant cardiologist with subspecialty training in echocardiography (odds ratio 8.7, P = 0.004), the presence of a stress echocardiography service (odds ratio 2.3, P = 0.004), and the presence of a physician during the day (odds ratio 3.0, P = 0.04). Reasons for impediment in administering contrast were staff training (34.6%), extra time required for a contrast study (29.9%), and the expense of contrast (18.7%).
Conclusion: The use of echocardiographic contrast agents within routine echocardiographic practice in the UK is limited to <4% of all transthoracic echocardiographic studies. Major barriers to the implementation of contrast use are the absence of cardiac imaging specialists directly supervising echocardiography departments and the training of sonographers to independently administer contrast.
Keywords: Contrast; Echocardiography.