Anthracycline Cardiotoxicity: How Do We Move From Diagnosis to Prediction?

Regular voluntary running has favorable histological effects on doxorubicin-induced kidney toxicity in Wistar rats

Knowing the therapeutic effects of regular physical exercise on kidney toxicity induced by a single dose of doxorubicin (DOX) in animal models, the aim of this study is to verify the effectiveness of regular voluntary running on kidney histology after a prolonged DOX administration, mimicking a chemotherapy protocol. Thirty-four male Wistar rats were randomly divided into two clusters: DOX (n = 17) and SSS (sterile saline solution, n = 17), receiving a weekly intraperitoneal injection of DOX (2 mg/kg) or vehicle for 7 weeks, respectively. Two weeks after the last injection, five animals from each cluster (SSSG, n = 5; DOXG, n = 5) were euthanized, while the remaining ones were divided into sedentary (DOXsed, n = 6; SSSsed, n = 6) and active subgroups (DOXact, n = 6; SSSact, n = 6). Active animals were placed individually in cages with a running wheel for regular voluntary activity. After 2 months, the animals were euthanized and kidneys were histologically examined. Compared to SSSG, kidneys from DOXG revealed higher levels of damage, more collagen content and thickening of Bowman's capsule (p < .05). The levels of damage and thickness of Bowman's capsule increased in DOXsed as compared to DOXG (p < .05). Compared to DOXsed, the DOXact presented an overall improvement in kidney structure (p < .05), with a decrease in collagen content and of the thickness of Bowman's capsule. The results allow concluding that regular voluntary running attenuate the long-term harmful effects on kidney structure induced by a prolonged DOX treatment. These results, supporting the potential benefit of physical activity in patients under DOX treatment, need to be tested in humans.

Usefulness of Integrating Heart Failure Risk Factors Into Impairment of Global Longitudinal Strain to Predict Anthracycline-Related Cardiac Dysfunction

The prediction of cancer therapeutics-related cardiac dysfunction (CTRCD) is an essential aspect of care for individuals who receive potentially cardiotoxic oncologic treatments. Certain clinical risk factors have been described for incident CTRCD, and measurement of left ventricular (LV) longitudinal strain by speckle tracking 2-dimensional echocardiography (2DE) is the best-validated myocardial mechanical imaging assessment to detect subtle changes in LV function during cancer treatment. However, the direct integration of clinical and imaging risk factors to predict CTRCD has not yet been extensively examined. This was a retrospective study of 183 women with breast cancer aged 50.9 ± 10.8 years who received treatment with anthracyclines (doxorubicin dose of 422 ± 69 mg/m², with 41.2% of subjects also receiving trastuzumab) and underwent 2DE at clinically determined intervals. CTRCD was diagnosed when LV ejection fraction dropped ≥10% to a subnormal (<53%) value by 2DE. Left ventricular global longitudinal strain (LV-GLS) was assessed offline. The risk prediction tool based only on clinical factors previously described by Ezaz et al was applied to our cohort and accurately stratified these subjects into low-, intermediate-, and high-risk groups, with incident CTRCD in 7.4%, 26.9%, and 54.6%, respectively (chi-square = 20.7, p <0.0001). We developed novel multivariate models to predict CTRCD using (1) demographic variables only (c = 0.8674), (2) echocardiographic (peak LV-GLS) variables only (c = 0.8440), or (3) a combination of demographic and echocardiographic variables, with the combined model exhibiting superior receiver-operating characteristics (c = 0.9629). In conclusion, estimation of CTRCD risk should integrate all available data, including both clinical variables and an imaging assessment.