Strange times indeed: the evolving significance of myocardial ischaemia and the dwindling importance of functional imaging

Adrian Ionescu

doi:10.47803/rjc.2021.31.1.3

Abstract

The ISCHEMIA trial is only the latest and most compelling link in a chain of evidence that suggests that myocardial ischaemia per se is not an appropriate treatment target for patients with stable coronary artery disease. This review is trying to make sense of the momentous and sometimes contradictory recent developments in the space of imaging for myocardial ischaemia.

Highlights

Myocardial revascularisation is arguably the most dynamic, revolutionary area of cardiology and perhaps of clinical medicine
Are we about to see its demise in the few years? And, as imaging specialists, how can we find our way in the rapidly-evolving field of ischaemia imaging?
The ISCHEMIA-CKD24 study showed no reduction in cardiac events with an invasive strategy and no improvement in symptoms or quality of life in patients with chronic renal failure. Both ORBITA25 and ISCHEMIA26 have been criticised on multiple fronts but, notwithstanding their imperfections, there is no doubt that, jointly, they have dealt a severe blow to the conventional paradigm of ischaemia in stable coronary artery disease (CAD), by suggesting that inducible myocardial ischaemia is not, after all, an appropriate target for treatment and for imaging, as relieving ischaemia does not appear to improve outcomes or symptoms in the era of aggressive medical treatment

Summary

INTRODUCTION

Myocardial revascularisation is arguably the most dynamic, revolutionary area of cardiology and perhaps of clinical medicine. The ISCHEMIA-CKD24 study showed no reduction in cardiac events with an invasive strategy and no improvement in symptoms or quality of life in patients with chronic renal failure Both ORBITA25 and ISCHEMIA26 have been criticised on multiple fronts but, notwithstanding their imperfections, there is no doubt that, jointly, they have dealt a severe blow to the conventional paradigm of ischaemia in stable CAD, by suggesting that inducible myocardial ischaemia is not, after all, an appropriate target for treatment and for imaging, as relieving ischaemia does not appear to improve outcomes or symptoms in the era of aggressive medical treatment. There is the option to continue as before, i.e. only perform invasive angiography if pre-test evidence of ischaemia has been obtained non-invasively This approach is, unlikely to prevail, both because the results of ISCHEMIA reduce the pressure to perform functional imaging, and, more importantly, because FFR and especially the much-simpler-to-perform iFR allow immediate diagnosis of functionally significant coronary stenoses in the cath lab, where immediate revascularisation can be carried out seamlessly in the same procedure. Over a followup of 2 years, the CTCA-first strategy offered no benefits over the functional testing strategy, with identical

Method Limitations

Findings

CONCLUSIONS