ABSTRACT
Bioresorbable vascular scaffolds (BRSs) are an emerging and novel treatment for coronary artery disease. Similar to but essentially differing from conventional metallic stents, they provide the short-term scaffolding required to prevent acute vessel closure during percutaneous coronary intervention (PCI), deliver antiproliferative drug in the same way as drug-eluting stent (DES). The first report of the pivotal ABSORB II randomized trial also hinted at patient benefits outside of conventional hard clinical outcome measures—a significant observed reduction in the rate of recurrent or worsening angina. Coronary microvascular dysfunction has been identified as a mechanism of myocardial ischemia that may operate both in and without the presence of conventional obstructive coronary artery disease. In contrast to epicardial responses, visualized angiographically, coronary microcirculatory function is tested indirectly, and may be assessed invasively or noninvasively. Epicardial coronary arteries are essentially conduit vessels with little resistance and therefore contribute minimally to overall coronary flow reserve (CFR).
