ABC | Volume 110, Nº3, March 2018

Review Article Ket et al Practical Implications of Myocardial Viability Studies Arq Bras Cardiol. 2018; 110(3):278-288 Despite its limitations and biases, the STICH trial is, so far, the largest study on the influence of myocardial viability on clinical outcomes in patients with ischemic heart disease. Also, it is the first study to evaluate differential results of revascularization and pharmacological therapy. 67 PARR-2 Trial Study designed to evaluate the efficacy of 18 F-FDG PET in patients with left ventricular dysfunction, by risk stratification and identification of those who would benefit frommyocardial revascularization. A total of 430 patients with LVEF < 35% and CAD were allocated into two groups – standard care (n = 212) and treatment assisted by 18 F-FDG PET (n = 218). 68 At one year, the PARR-2 trial did not show a significant difference between the groups in the primary outcomes that included death for cardiac causes, acute myocardial infarction or hospital stays for cardiac cause (30% vs. 36% p = 0.15). In PET group, however, there was a significant decrease in primary outcome over the follow-up period (relative risk 0.62; 95% CI 0.42 – 0.93; p = 0.019). 68 Perspectives Myocardial viability is still a subject of clinical importance and a focus of clinical trials and translational science. Pathophysiological basis of left ventricular ischemic dysfunction seems to be correlated with myocardial stunning, hibernation or myocardial necrosis. Imaging methods used for assessment of viable muscular tissue have their own operational characteristics and should be appropriate to the patient’s individual characteristics. The detection of myocardial viability may be a valuable predictor of the response to revascularization and long-term prognostic and, thereby, contribute to the decision-making in the medical practice. 18 F-FDG PET and CMR are considered first-choice methods for detection of viability due to their high sensitivity and specificity rates, whereas both echocardiography and myocardial scintigraphy considered acceptable methods for their wide availability and accessibility. With respect to the impact on medical practice, there are no definite studies showing the benefits of myocardial viability assessment on patients’ prognosis, which reinforce the necessity of larger studies, considering the great relevance of the theme. Author contributions Conception and design of the research, Acquisition of data, Analysis and interpretation of the data, Writing of themanuscript and Critical revision of the manuscript for intellectual content: Ker WS, Nunes THP, Nacif MS, Mesquita CT; Obtaining financing: Ker WS, Nacif MS, Mesquita CT Potential Conflict of Interest No potential conflict of interest relevant to this article was reported. Sources of Funding There were no external funding sources for this study. Study Association This article is part of the thesis of master submitted by Wilter dos Santos Ker, fromUniversidade Federal Fluminense. Ethics approval and consent to participate This article does not contain any studies with human participants or animals performed by any of the authors. 1. Anavekar NS, Chareonthaitawee P, Narula J, Gersh BJ. Revascularization in patients with severe left ventricular dysfunction. is the assessment of viability still viable? J Am Coll Cardiol. 2016;67(24):2874-87. 2. 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