Is there a role for fractional flow reserve in coronary artery bypass graft (CABG) planning?

Abstract

The concept of significant lesions has substantially evolved over the last decade. With growing evidence for use of fractional flow reserve (FFR) as a determinant of lesion-specific ischemia and its superiority to angiography-guided revascularization and medical therapy, the field of percutaneous revascularization has shifted to rely exclusively on FFR instead of luminal stenosis alone in guiding revascularization. This transition to physiological assessment has not yet made it to the realm of surgical revascularization. FFR-guided therapy has been shown to be superior to angiography-guided therapy mainly by safe deferral of about 1/3rd of lesions, leading to less periprocedural events and better outcomes. Is it possible that utilization of FFR-guided CABG would lead to less complicated procedures, shorter operating times, more frequent off pump CABG procedures and more hybrid procedures? Can FFR-guided CABG improve the cardiovascular outcomes as compared to current standard of practice? In the following paragraphs we review the concept of FFR, the evidence behind FFR-guided therapy, the emerging data regarding use FFR-guided CABG and discuss where the revascularization field is headed.

The new role of diagnostic angiography in coronary physiological assessment

“…The patients most deserving of physiological guidance are those with multivessel disease being considered for CABG. 17 However, very few receive pressure wire assessment prior to CABG, and often, referral for surgery is based on a CAG performed in a non-interventional CCL. Further guidance with FFR would require a second visit to a CCL, with associated delays, and is therefore rarely done.…”

What will surgical coronary revascularization look like in 25 years?

“…As such, suboptimal medical management in CABG as shown in many randomized trials needs further optimization by means of adopting recent guidelines recommendations [63,64]. To further improve outcomes in CABG, recent trends of preoperative conditioning by means of improving the functional capacity through multimodal prehabilitation (preoperative rehabilitation) programs need further attention [65].…”

Changes in surgical revascularization strategy after fractional flow reserve

“…In patients with stable coronary artery disease, an invasive haemodynamic evaluation such as fractional flow reserve (FFR) is recommended in the absence of documented ischemia at non‐invasive imaging testing in order to decide if a stenotic vessel needs to be revascularized or not 1,2 . In the field of percutaneous coronary intervention (PCI), randomized clinical trials demonstrated the benefit of FFR‐guidance 3‐9 but the level of evidence is not as high in the field of surgical revascularisation 10 . Retrospective data suggest that ‐ as compared to angiography‐guided coronary artery bypass graft (CABG) surgery ‐ FFR‐guided CABG surgery is associated with a simplified surgical intervention and with a higher graft patency rate at 6 years, 11 leading to a significantly lower rate of overall death and myocardial infarction 12 .…”

“…1,2 In the field of percutaneous coronary intervention (PCI), randomized clinical trials demonstrated the benefit of FFR-guidance [3][4][5][6][7][8][9] but the level of evidence is not as high in the field of surgical revascularisation. 10 Retrospective data suggest that -as compared to angiography-guided coronary artery bypass graft (CABG) surgery -FFR-guided CABG surgery is associated with a simplified surgical intervention and with a higher graft patency rate at 6 years, 11 leading to a significantly lower rate of overall death and myocardial infarction. 12 More recently, in the single-blinded prospective multicenter randomized controlled trial for FFR-guided versus angiography-guided CABG (GRAFFITI) trial, FFR-guided CABG was also associated with a significantly simplified surgical procedure without impact on 1-year graft patency.…”