Ischemic burden or anatomic burden: which non-invasive testing in stable patients with suspected coronary artery disease?

Abstract

Guidance on the diagnostic approach to coronary artery disease has diverged as the increasing complexity of atherosclerotic clinicopathologic correlations has been revealed. Foundational concepts linking stenosis, the ischaemic cascade and prognosis have been re-evaluated in light of the underwhelming results from the percutaneous revascularization of stenotic vessels. These studies have revealed ischaemia to be an important marker for cardiovascular outcomes, but likely separate from the causal pathway of hard clinical events. Instead, observations from non-invasive anatomical imaging have redefined risk, shifting the focus away from discrete lesions towards total atherosclerotic burden, and with it elevating the role of computed tomography in contemporary diagnostic pathways. As it currently stands, functional and anatomical approaches provide complementary information; stress testing continues to provide guidance for potential revascularization in current guidelines, yet anatomical testing may additionally identify individuals likely to benefit from preventive therapy. While guidelines attempt to keep pace with the advancing technology and expanding literature, clinicians are left to apply clinical acumen to decide on a vast and confusing array of investigative options. This review will deal with strenghts and limitations of the current approach to the diagnosis of coronary artery disease, providing the rationale for both functional and anatomical approaches.