Effect of increase in heart rate after anthracycline chemotherapy on subsequent left ventricular dysfunction

Anthracycline chemotherapy-related cardiac dysfunction is believed to be refractory to conventional pharmacological therapy and is associated with a poor prognosis. Increased heart rate (HR) is a known marker of cardiovascular outcomes for various categories of heart failure (HF). However, little interest has been expressed regarding increased HR after anthracycline chemotherapy. Aim of this study was to investigate the effect of increased HR soon after completion of anthracycline chemotherapy on subsequent left ventricular (LV) ejection fraction (LVEF) in cancer patients.

We studied 172 patients with breast cancer and malignant lymphoma with preserved LVEF (≥ 50 %) and sinus rhythm treated with anthracyclines. Electrocardiography was performed before and soon after completion of anthracycline chemotherapy (2.3 months), and echocardiography before and late after completion of anthracycline chemotherapy (10.5 months).

HR significantly increased from 74.2 ± 14.2 bpm to 75.9 ± 13.2 bpm (P = 0.05) soon after completion of anthracycline chemotherapy, while LVEF subsequently significantly decreased from 65.3 ± 5.5 % to 62.4 ± 6.1 % (P < 0.01) late after completion of anthracycline chemotherapy. Patients whose HR increased ≥10 bpm subsequently showed a significantly greater decrease in LVEF than those whose HR increased <10 bpm [-4.9 % (-32.7 % - 10.8 %) vs. -2.2 % (-21.2 % - 12.9 %), p = 0.04]. Multivariable logistic regression analysis showed that an increase in HR soon after completion of anthracycline chemotherapy was independently associated with a subsequent decrease in LVEF (odds ratio: 1.022, 95 % confidential interval; 1.008-1.037, P = 0.002).

Our findings may have a novel effect on the management of cancer patients scheduled for anthracycline chemotherapy.