IJCS | Volume 32, Nº1, January/ February 2019

73 Figure 2 - “Regional wall motion abnormality and functional recovery in the long-term course. The wall motion abnormality early after AMI and at follow-up as well as the resulting functional recovery of the 95 dysfunctional segments were evaluated regarding different patterns of LGE transmurality and FDG uptake [LGE transmurality (A and D), FDG uptake (B and E), combination of LGE transmurality and FDG uptake (C and F)] “- With permission from Rischpler et al, Eur Heart J Cardiovasc Imaging. 30 AMI: acute myocardial infarction; LGE: late gadolinium enhancement; PET: positron emission tomography; MR: magnetic resonance imaging. Erthal et al. Myocardial viability: from PARR-2 to IMAGE HF - current evidence and future directions Int J Cardiovasc Sci. 2019;32(1)70-83 Review Article with ischemic HF. 9,31–34 Allman et al. 9 have conducted a meta-analysis with 24 studies, and their analysis has shown the benefit of revascularization only in patients with viable myocardium as opposed to scar. 9 More recently, a meta-analysis including 29 studies by Inaba et al. has documented the benefit of revascularization over medical therapy in patients with dysfunctional viable myocardium. 31 To date, there have been two major prospective randomized trials comparing outcome in patients with ischemic HF who underwent viability assessment: PARR-2 (Positron emission tomography And Recovery following Revascularization phase 2) 6 and STICH (Surgical Treatment for Ischemic Heart Failure) viability substudy 35 trials. PARR-2 has randomized 430 patients from 9 centers, to have either viability assessment with 18 FDG PET or standard care without 18 FDG PET, before decisions regarding revascularization. 6 A trend toward benefit for the primary outcome (cardiac death, MI and cardiac hospitalization at 1 year) has been observed in the arm that underwent FDG PET to assist with clinical decision- making [36% of events in the standard care arm and 30% in the PET arm, relative risk 0.82; p = 0.16 and hazard ratio (HR) 0.78; p = 0.15]. 6 However, not all patients in the study followed the imaging recommendation. When analyzing only the patients who adhered to the recommendations from the imaging report, a significant reduction in outcome was observed in the PET arm versus standard care (HR 0.62; p = 0.019), indicating that