UNASSIGNED: Women treated for breast cancer are at risk for worsening health-related quality of life (QoL), cardiac function, and cardiorespiratory fitness.
UNASSIGNED: The aim of this study was to assess the associations of self-reported moderate to vigorous intensity physical activity (MVPA) during cancer treatment with concurrent measures of QoL and cardiac function and with post-treatment cardiorespiratory fitness in women with human epidermal growth factor receptor 2-positive breast cancer receiving sequential anthracyclines and trastuzumab.
UNASSIGNED: EMBRACE-MRI 1 (Evaluation of Myocardial Changes During Breast Adenocarcinoma Therapy to Detect Cardiotoxicity Earlier With MRI) study participants who completed questionnaires for MVPA (modified Godin Leisure Time Physical Activity Questionnaire) and QoL (EQ-5D-3L, Minnesota Living With Heart Failure Questionnaire) and cardiac imaging every 3 months during treatment and post-treatment cardiopulmonary exercise testing were included. Participants engaging in ≥90 minutes of MVPA each week were labeled \"active.\" Generalized estimation equations and linear regression analyses were used to assess concurrent and post-treatment associations with MVPA and activity status, respectively.
UNASSIGNED: Eighty-eight participants were included (mean age 51.4 ± 8.9 years). Mean MVPA minutes, QoL, and cardiac function (left ventricular ejection fraction, global longitudinal strain, E/A ratio, and E/e\' ratio) worsened by 6 months into trastuzumab therapy. Higher MVPA (per 30 minutes) during treatment was associated with better concurrent overall (β = -0.42) and physical (β = -0.24) Minnesota Living With Heart Failure Questionnaire scores, EQ-5D-3L index (β = 0.003), visual analogue scale score (β = 0.43), diastolic function (E/A ratio; β = 0.01), and global longitudinal strain (β = 0.04) at each time point (P ≤ 0.01 for all). Greater cumulative MVPA over the treatment period was associated with higher post-treatment cardiorespiratory fitness (peak oxygen consumption; β = 0.06 per 30 minutes; P < 0.001).
UNASSIGNED: Higher self-reported MVPA during treatment for human epidermal growth factor receptor 2-positive breast cancer was associated with better QoL and diastolic and systolic left ventricular function measures during treatment and better post-treatment cardiorespiratory fitness.

Cardiotoxicity is a relatively frequent and potentially serious side effect of traditional and targeted cancer therapies. Both general measures and specific pharmacologic cardioprotective interventions as well as imaging- and biomarker-based surveillance strategies to identify patients at high risk have been tested in randomized controlled trials to prevent or attenuate cancer therapy-related cardiotoxic effects. Although meta-analyses including early trials suggest an overall beneficial effect, there is substantial heterogeneity in results. Recent randomized controlled trials of neurohormonal inhibitors in patients receiving anthracyclines and/or human epidermal growth factor receptor 2-targeted therapies have shown a lower rate of cancer therapy-related cardiac dysfunction than previously reported and a modest or no sustained effect of the interventions. Data on preventive cardioprotective strategies for novel cancer drugs are lacking. Larger, prospective multicenter randomized clinical trials testing traditional and novel interventions are required to more accurately define the benefit of different cardioprotective strategies and to refine risk prediction and identify patients who are likely to benefit.

The objective of this study was to determine associations of paraoxonase-1 (PON-1) with development of cancer therapy-related cardiac dysfunction (CTRCD). PON-1 is a cardioprotective enzyme associated with high-density lipoprotein that prevents oxidized low-density lipoprotein formation. Given the role of oxidative stress in doxorubicin-induced cardiotoxicity, PON-1 activity may have relevance for the prediction of CTRCD. In 225 patients with breast cancer receiving doxorubicin with or without trastuzumab, we quantified PON-1 activity through its paraoxonase (Pon) and arylesterase (Aryl) enzymatic activity at baseline, during, and after doxorubicin completion. Echocardiograms were performed at baseline, during therapy, and annually. CTRCD was defined as a decrease in left ventricular ejection fraction by ≥10% from baseline to <50%. Associations between baseline biomarkers and clinical variables were determined using multivariable linear regression. Associations between changes in biomarker activity and time to CTRCD were evaluated using Cox regression. Pon was directly associated with Black race and inversely associated with Stage 2 cancer. Aryl was inversely associated with body mass index. After doxorubicin completion, activity levels of Pon and Aryl were significantly decreased (median ratio compared with baseline for Pon: 0.95 [Q1-Q3: 0.81-1.07, P < 0.001]; for Aryl: 0.97 [Q1-Q3: 0.85-1.08, P = 0.010]). A total of 184 patients had an available quantitated echocardiogram at baseline and at least 1 follow-up visit. Increases from baseline in Pon at doxorubicin completion were independently associated with increased CTRCD risk (per 10% increase: hazard ratio [HR]: 1.21; 95% confidence interval [CI]: 1.05-1.39; P = 0.007). Associations between increases in Aryl and CTRCD tended in the same direction but were of borderline statistical significance (HR: 1.17; 95% CI: 0.99-1.38; P = 0.071). In patients with breast cancer treated with doxorubicin with or without trastuzumab, increases in the Pon enzymatic activity level of PON-1 were associated with increased CTRCD risk. PON-1 activity may be relevant to mechanistic risk prediction of cardiotoxicity with anthracyclines.

BACKGROUND: Cardiorespiratory fitness (CRF) is reduced in cancer survivors and predicts cardiovascular disease (CVD)-related and all-cause mortality. However, routine measurement of CRF is not always feasible.
OBJECTIVE: The purpose of this study was to identify clinical, cardiac biomarker, and imaging measures associated with reduced peak oxygen consumption (VO2peak) (measure of CRF) early post-breast cancer therapy to help inform CVD risk.
METHODS: Consecutive women with early-stage HER2+ breast cancer receiving anthracyclines and trastuzumab were recruited prospectively. Within 6 ± 2 weeks of trastuzumab completion, we collected clinical information, systolic/diastolic echocardiographic measures, high-sensitivity troponin I, B-type natriuretic peptide, and VO2peak using a cycle ergometer. Regression models were used to examine the association between VO2peak and clinical, imaging, and cardiac biomarkers individually and in combination.
RESULTS: Among 147 patients (age 52.2 ± 9.3 years), the mean VO2peak was 19.1 ± 5.0 mL O2·kg-1·min-1 (84.2% ± 18.7% of predicted); 44% had a VO2peak below threshold for functional independence (<18 mL O2·kg-1·min-1). In multivariable analysis, absolute global longitudinal strain (GLS) (β = 0.58; P = 0.007), age per 10 years (β: -1.61; P = 0.001), and E/e\' (measure of diastolic filling pressures) (β = -0.45; P = 0.038) were associated with VO2peak. GLS added incremental value in explaining the variability in VO2peak. The combination of age ≥50 years, E/e\' ≥7.8, and GLS <18% identified a high probability (85.7%) of compromised functional independence, whereas age <50 years, E/e\' <7.8, and GLS ≥18% identified a low probability (0%). High-sensitivity troponin I and B-type natriuretic peptide were not associated with VO2peak.
CONCLUSIONS: Readily available clinical measures were associated with VO2peak early post-breast cancer therapy. A combination of these parameters had good discrimination to identify patients with compromised functional independence and potentially increased future CVD risk.

The subspecialty of cardio-oncology aims to reduce cardiovascular morbidity and mortality in patients with cancer or following cancer treatment. Cancer therapy can lead to a variety of cardiovascular complications, including left ventricular systolic dysfunction, pericardial disease, and valvular heart disease. Echocardiography is a key diagnostic imaging tool in the diagnosis and surveillance for many of these complications. The baseline assessment and subsequent surveillance of patients undergoing treatment with anthracyclines and/or human epidermal growth factor receptor (HER) 2-positive targeted treatment (e.g., trastuzumab and pertuzumab) form a significant proportion of cardio-oncology patients undergoing echocardiography. This guideline from the British Society of Echocardiography and British Cardio-Oncology Society outlines a protocol for baseline and surveillance echocardiography of patients undergoing treatment with anthracyclines and/or trastuzumab. The methodology for acquisition of images and the advantages and disadvantages of techniques are discussed. Echocardiographic definitions for considering cancer therapeutics-related cardiac dysfunction are also presented.

Cancer therapy-related cardiac dysfunction (CTRCD) is one of the most concerning cardiovascular side effects of cancer treatment. Important reviews within the field of cardio-oncology have described various agents to be associated with a high risk of CTRCD, including mitomycin C, ifosfamide, vincristine, cyclophosphamide, and clofarabine. The aim of this study was to provide insight into the data on which these incidence rates are based. We observed that the reported cardiotoxicity of mitomycin C and ifosfamide is based on studies in which most patients received anthracyclines, complicating the interpretation of their association with CTRCD. The high incidence of vincristine-induced cardiotoxicity is based on an incorrect interpretation of a single study. Incidence rates of clofarabine remain uncertain due to a lack of cardiac screening in clinical trials. The administration of high-dose cyclophosphamide (>1.5 g/m2/day) is associated with a high incidence of CTRCD. Based on our findings, a critical re-evaluation of the cardiotoxicity of these agents is warranted.