April 10, 2013 – Pamela Douglas, MD, Director of the DCRI Imaging Group, served as first author of the analysis of imaging in the PARTNER I trial.
The use of quality assurance measures in echocardiography can ensure a high degree of measurability and reproducibility, according to a recent study led by Pamela Douglas, MD, director of the DCRI Imaging Program.
Results of the study appear in the most recent issue of the Journal of the American Society of Echocardiography. The DCRI’s Robert A. Waugh, MD, Gerald Bloomfield, MD, Gary Dunn, MBA, and LaGia Davis, MS, CCRP, were co-authors, along with colleagues from across the United States and Canada.
Large, multi-center clinical trials make frequent use of echocardiographic core laboratories (ECLs) to ensure quality and consistency in the assessment of imaging eligibility. Echocardiography’s relatively low cost and unique ability to capture heart functions account for its popularity as a data collection tool, but varying methods of interpretation mean it is less often used for trial end points. Guidelines exist regarding best practices in ECLs, but until now there has been little research into their implementation.
For this study, Douglas and her colleagues developed a set of processes to optimize the acquisition and analysis of echocardiograms for the Placement of Aortic Transcatheter Valves (PARTNER) I trial of percutaneous aortic valve replacement for aortic stenosis. PARTNER I was the first randomized clinical trial to study valve implants and enrolled 1,055 patients with severe aortic stenosis at 26 sites across the United States.
Douglas and her research team created processes related to PARTNER I’s ECL work flow, reproducibility testing, image acquisition, quality assurance, image transfer and management, study interpretation, and final data checks. They then compared the baseline findings in the operative and nonoperative cohorts of PARTNER I and performed reproducibility analyses.
Upon reviewing the images gathered during PARTNER I, the researchers found that ECL reproducibility was excellent, with intra-class correlation coefficients ranging from 0.92 to 0.99 and k statistics from 0.58 to 0.85 for key variables. The image acquisition quality improvement process brought measurability to greater than 85 percent, which was maintained until the completion of the study.
Douglas and her colleagues concluded that it is possible to implement stringent quality control measures in clinical trials to ensure high image measurability and reproducibility. By adhering closely to a set of rigorously defined criteria, they noted, researchers can obtain reliable and reproducible images. Given that these images play an outsized role in trials where the results are based directly on echocardiographic data, such as PARTNER I, the existing protocols and processes should be widely adopted for future studies.