ABC | Volume 112, Nº3, March 2019

Review Article Jorge et al Imaging for chemotherapy-related ventricular dysfunction Arq Bras Cardiol. 2019; 112(3):309-316 Subclinical detection of left ventricular dysfunction To date, there is no evidence regarding the treatment of asymptomatic patients with preserved LVEF and alterations exclusively in strain. However, the rationale for measuring strain is based on the possibility of frequently monitoring patients at risk and, as soon as a decrease in LVEF is detected, initiating therapy and obtaining reverse remodeling. For the purpose of detecting subclinical dysfunction, baseline LVGLS is the marker for comparison of post-CT measurements. A relative reduction of more than 15% can confirm the dysfunction. This altered value should be confirmed by a new exam 2 or 3 weeks later. Elevated TnI with or without alterations in LVGLS is also considered a marker of myocardial injury; there are, however, multiple causes of elevations in TnI, as well as doubts regarding its prognostic value for ventricular dysfunction. Whenever the need for suspending CT is considered in asymptomatic patients, it is necessary to measure LVEF using a more accurate method, such as RNV or CMRI. 8 There are no studies with safe levels of evidence demon s t r a t i ng t he bene f i t s o f pha rmaco l og i ca l “cardioprotective” treatment in patients undergoing CT. When considering the hypothesis of continuing CT notwithstanding alternations in LV function, echocardiographic re-evaluation is necessary before the new cycle, with the awareness that the risk of CTX will progressively increase. Additional imaging exams are not necessary for patients who have concomitant risk factors, in the presence of normal GLS or troponins during CT and 6 months after the last CT with ANT. Following completion of the therapeutic regimen, there should be annual clinical cardiovascular examination and the use of cardiac imaging in accordance with the services available. 8 Conclusions Monitoring LVEF by 2D ECHO is the most executable strategy for detecting CT-related cardiovascular disease in large groups of patients; this method should, however, be considered in the context of its numerous limitations. 3D ECHO is the method of choice when considering accuracy together with availability, limitations regarding repetition, and ease of execution. When this is not available, the addition of contrast to 2D ECHO should be encouraged, seeing that this increases accuracy. LVGLS is the best parameter of myocardial deformation for subclinical detection of LV dysfunction; however, there is no solid evidence showing the benefits of initiating early “cardioprotective” therapy based on its results. RNV has a high diagnostic accuracy for ventricular dysfunction and may be an alternative in the event of doubts regarding echocardiography. CMRI assists in differential diagnoses with other causes of cardiomyopathies. The decision to interrupt or continue a chemotherapeutic regimen is clinical, joint, and multidisciplinary, and it is based on the risk-benefit ratio for each patient. Randomized controlled clinical trials with long-term follow-up are necessary to determine whether early detection of cardiac dysfunction is a predictor of LVEF reduction and, above all, HF and major cardiovascular events. Author contributions Conception and design of the research: Ribeiro ML, Martins WA; acquisition of data and analysis and interpretation of the data: Ribeiro ML; writing of the manuscript and critical revision of the manuscript for intellectual content: Jorge AJL, Ribeiro ML, Nacif MS, Martins WA. 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 Doctoral submitted byMário Luiz Ribeiro, from Universidade Federal Fluminense. 314