The hibernating myocardium: current concepts, diagnostic dilemmas, and clinical challenges in the post-STICH era

A very large body of evidence--predominantly retrospective--suggests that revascularization is superior to optimal medical therapy in patients with a significant amount of 'hibernating' myocardium. Contemporary cardiological practice has embraced this standard of practice, as many centres worldwide place great emphasis upon the results of viability testing by non-invasive imaging techniques in determining the need for coronary revascularization. This practice has been challenged by the recent results of the Surgical Treatment for Ischaemic Heart Failure (STICH) trial, which suggested both lack of mortality benefit from revascularization and also from viability testing. In this review article, we have summarized the pathophysiology of hibernating myocardium, briefly discussed each of the non-invasive imaging modalities used in contemporary practice for detecting myocardial hibernation before critically appraising the prospective studies in this field, most importantly the main STICH trial and viability sub-study. STICH was clearly a complex trial but has not ended the question over the benefit of revascularization in ischaemic heart failure. Finally, we have suggested a possible methodology for an 'ideal trial' designed to evaluate the role of revascularization in such patients and also explored how viability testing should be used in clinical practice in the post-STICH era.