A selective approach to coronary revascularization among patients undergoing transcatheter aortic valve replacement
Transcatheter aortic valve replacement (TAVR) for severe aortic stenosis (AS) is now approved in the USA for extreme, high, and intermediate surgical-risk patients, with nearly 25 000 procedures performed in 2015 1. Coronary revascularization protocols used in the landmark trials that served as the basis for Food and Drug Administration approval of both the Edwards and Medtronic systems are implicitly incorporated into Food and Drug Administration labeling and subsequent coverage decisions 2. It is important to recall that the prevalent use of TAVR has come to bear by rigorous comparison with surgical aortic valve replacement (SAVR) as a gold standard. In the surgical setting, concomitant angiographic coronary artery disease (CAD) is treated with coronary artery bypass grafting (CABG) at the time of SAVR. Despite limitations surrounding lesion assessment using coronary angiography alone, stenoses with angiographic severity more than 50% have historically been treated with CABG. In more contemporary practice, functional assessment of intermediate lesions (50–70% angiographic stenosis) using fractional flow reserve (FFR) has been shown to improve outcomes among patients undergoing percutaneous coronary intervention (PCI) 3. Furthermore, studies have confirmed that complete FFR assessment among patients with multivessel disease leads to reclassification and often downgrading of the extent of disease 4. Despite the advantage of functional coronary lesion assessment, evaluation with vasodilator therapy as required with FFR comes with a risk in patients with severe AS. Although the use of physiological indices that do not require induction of hyperemia such as instantaneous wave-free ratio could be considered, to date, operator-driven selective PCI on the basis of angiography alone before TAVR has become the de facto modus operandi, but remains a prospectively untested strategy.
The Interventional Section of the American College of Cardiology recently published a position statement on this topic, advocating a strategy of pre-TAVR coronary angiography and selective PCI of proximal epicardial or left main vessels 2. The statement appropriately left the arena open for clinician judgment and supports a more selective approach to coronary revascularization among patients undergoing TAVR (Fig. 1).