420ORole of cardioprotective therapies for prevention of cardiotoxicity in breast cancer: A systematic review and meta-analysis

Abstract Background Cardiotoxicity is a well-recognized adverse outcome following adjuvant breast cancer treatment including anthracyclines, trastuzumab, and chest radiation. Its prevention remains an important challenge in clinical practice. We aimed to determine the effectiveness of prophylactic cardioprotective agents in preventing treatment-related cardiotoxicity in women with breast cancer. Methods A systematic review of published literature was conducted by searching PubMed, EMBASE and EBSCO host databases. Studies where prophylactic intervention was given to breast cancer patients without a prior history of heart disease were included. The outcomes of interest were preservation of left ventricular ejection fraction (LVEF), or development of cardiac events. Mean differences (MD) in LVEF, and relative risks (RR) of cardiac events, were evaluated using random-effects models. Results Thirteen randomized controlled trials (RCTs), which used prophylactic beta-blockers, dexrazoxane, angiotensin receptor blockers, angiotensin converting enzyme (ACE) inhibitors or other pharmacologic agents were included. Overall, the use of prophylactic cardioprotective agents resulted in a statistically significant smaller LVEF decline compared to use of placebo (MD = 2.42%, 95% confidence interval (CI): 0.59%-4.24%). While there were 52 cardiac events in the intervention arm (n = 405) compared to 79 in the control arm (n = 396), use of prophylactic cardioprotective agents did not significantly protect against incident cardiac events (RR = 0.63, 95%CI: 0.33-1.22). Conclusions In breast cancer patients without a history of heart disease, use of cardioprotective agents appear to confer only a very marginal protection against LVEF decline, falling below the ideal 10% cardioprotection. However, given the sample number of RCTs in this area, more studies are needed to substantiate the effectiveness of prophylactic cardioprotective agents in prevention of cardiotoxicity in women with breast cancer. Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest.