Association between clinical risk factors and left ventricular function in patients with breast cancer following chemotherapy.

The sequential or concurrent use of two different types of agents such as anthracyclines and trastuzumab may increase myocardial injury and cancer therapeutics-related cardiac dysfunction (CTRCD), which is often the result of the combined detrimental effect of the two therapies for breast cancer patients. However, the association between clinical risk factors and left ventricular (LV) function in such patients is currently unclear. We studied 86 breast cancer patients with preserved LV ejection fraction (LVEF) and treated with anthracyclines, trastuzumab, or both. Echocardiography was performed before and 16 days after chemotherapy. In accordance with the current position paper, clinical risk factors for CTRCD were defined as: cumulative dose of doxorubicin > 240 mg/m2, age > 65-year-old, body mass index > 30 kg/m2, previous radiation therapy, B-type natriuretic peptide > 100 pg/mL, previous history of cardiovascular disease, atrial fibrillation, hypertension, diabetes, and smoking. The relative decrease in LVEF after chemotherapy for patients with more than four risk factors was significantly greater than that for patients without (- 9.3 ± 10.8% vs. - 2.2 ± 10.2%; p = 0.02). However, this finding did not apply to patients with more than one, two or three risk factors. Patients with more than four risk factors also tended to show a higher prevalence of CTRCD than those without (14.3% vs. 2.8%; p = 0.12). Moreover, the relative decrease in LVEF became greater as the number of risk factors increased. This study found multiple risk factors were associated with LV dysfunction following chemotherapy. Our findings can thus be expected to have clinical implications for better management of patients with breast cancer referred for chemotherapy.