Log in to MyACC
Randomized Trials in Cardiac Surgery
Study Questions:
What are some of the challenges in conducting randomized controlled trials (RCTs) in cardiac surgery?
Methods:
This review article identifies challenges in conducting high-quality RCTs in cardiac surgery. The authors highlight issues with equipoise, blinding, influence of surgeon expertise and volume-outcome relationships, incompletely defined intervention or outcomes, funding, recruitment/retention, and data analysis.
The authors illustrate some of these challenges with examination of data. They conducted three separate searches of RCTs. The first used a set of cardiac surgery-related search terms to search Ovid MEDLINE for all cardiac surgical studies published from 2000-2019 in 10 notable journals (Annals of Thoracic Surgery, British Medical Journal, Circulation, European Heart Journal, European Journal of Cardio-thoracic Surgery, Journal of the American College of Cardiology, Journal of the American Medical Association, Journal of Thoracic and Cardiovascular Surgery, Lancet, and New England Journal of Medicine).
The second was a comprehensive literature search to identify coronary, vascular, structural heart and interventional cardiology, vascular, and cardiac surgery trials performed from 2000-2019. The authors determined whether the trials were industry-sponsored, industry-initiated and sponsored, or investigator-initiated, and further determined whether the trials investigated an intervention or a device.
The third was a search in clinicaltrials.gov to determine the number of registered trials, registered and completed trials, and those specific to cardiac surgery from 2000-2019. Statistical analysis was performed with linear regression for temporal trends. Chi-square test of proportions was used to compare groups.
Results:
From Ovid MEDLINE, 27,934 cardiac surgery studies were retrieved, of which 302 RCTs written in English were analyzed. While there was no significant difference in the number of all types of cardiac surgical studies published over the time period (p for trend = 0.44), there was a significant decrease in the number of cardiac surgical RCTs (p for trend < 0.001).
Of 6,564 possible cardiovascular and interventional trials, 216 RCTs were eligible for analysis. The authors found that the number of interventional trials was >2 times higher than the number of surgery trials. Also, significantly more cardiac surgery trials were investigator initiated (37 of 64, 58%), whereas 100 of 175 (57%) interventional trials were industry-sponsored (p = 0.04).
Last, there was a significant difference in the number of total completed and total registered interventional trials compared to completed and registered cardiac surgical trials (p for trend < 0.001).
Conclusions:
Conducting RCTs in cardiac surgery is associated with unique challenges that should be acknowledged and addressed in order to improve the quality of data that results from RCTs in this specialty.
Perspective:
In the setting of controversy surrounding the EXCEL trial and some of the transcatheter aortic valve trials, Gaudino et al.’s review is timely and spot on. They point out issues that all of us—physicians, surgeons, experts in clinical trial design, statisticians, and epidemiologists—need to honestly address so that cardiac surgery RCTs can best answer the questions posed, and their results are considered valid and appropriate to use to benefit our patients. The authors’ recommendations for trial design, implementation, and analysis should be considered by all who plan to conduct an RCT in cardiac surgery.
Clinical Topics: Cardiac Surgery, Invasive Cardiovascular Angiography and Intervention
Keywords: Cardiac Surgical Procedures, Cardiology Interventions, Clinical Trials as Topic, Outcome Assessment, Health Care, Transcatheter Aortic Valve Replacement, Vascular Diseases
< Back to Listings
