Why is there discussion on social media about CABG in the ISCHEMIA trial?

The ACC/AHA (and other societies) 2021 guideline writing committee for revascularization of patients with stable coronary disease revised the recommendation for CABG to improve overall survival in patients with 3-vessel disease and preserved ejection fraction from Class 1 to Class 2b. This significant change in guidelines sparked a controversy. AATS and STS withdrew their support of the guidelines.

According to the process for development of guideline recommendations, the totality of evidence is considered when a recommendation is created or revised. ISCHEMIA was included as evidence cited to support the revised recommendation for CABG.

Understandably, controversy surrounding the guidelines has led to more intensive scrutiny of ISCHEMIA data. Questions have been raised online about data accuracy across ISCHEMIA manuscripts. We communicated with investigators about this separately. That communication, and additional details addressing concerns raised about concordance of results between the primary report and secondary analyses are available here on the ISCHEMIA website.

Is it true that one of the ISCHEMIA Steering Committee members recently resigned?

Yes. Dr. Bruce Ferguson, who served on the Leadership and Steering Committees and chaired the CABG Subcommittee of the ISCHEMIA Optimal Revascularization Planning Committee from trial inception, announced his resignation.

What was the process for developing CABG site certification and selecting sites to perform CABG for trial participants?

Comments were made online about the quality of CABG in the trial. The process was rigorous. The site and operator selection criteria were developed by the CABG Subcommittee of the ISCHEMIA Optimal Revascularization Planning Committee. The ISCHEMIA Optimal Revascularization Planning Committee, the Steering Committee and the Leadership Committee approved site qualification criteria for performance of revascularization procedures, including requirements for cardiac surgeon participation and site selection with respect to CABG performance. The same committee defined optimal anatomic and functional revascularization with CABG for the trial.  They may be found in Table S2 of the ISCHEMIA design paper, here. The membership of ISCHEMIA committees appears here.

Who serves as the Statistical and Data Coordinating Center for ISCHEMIA?

The Duke Clinical Research Institute (DCRI) has served as the Statistical and Data Coordinating Center. DCRI has done a remarkable job ensuring data integrity. Academic statisticians at Duke, NYU and Mid-America Heart Institute have analyzed study data and have performed sophisticated statistical analyses. These analyses are undertaken after thorough discussion of a statistical analysis plan with the ISCHEMIA Publications Committee. Manuscripts are approved by the ISCHEMIA Publications Committee. This process helps assure the integrity of the data and analyses.

We are steadfast in our commitment to analyze and publish ISCHEMIA data while adhering to the highest scientific standards, whether the results are consistent with or are counter to our hypothesis and expectations.

Can other research groups verify ISCHEMIA data reports?

Yes. The data sharing platform is NHLBI BioData Catalyst. It is open to all researchers. The process of making ISCHEMIA data, including data on coronary vessel disease severity, available within BioData Catalyst is underway.