SAFE-HEaRt: A pilot study assessing the cardiac safety of HER2 targeted therapy in patients with HER2 positive breast cancer and reduced left ventricular function.

1038Background: HER2 targeted therapies have substantially improved the prognosis of patients with BC however they can be associated with cardiac toxicity. SAFE-HEaRt is the first investigator-initiated trial that prospectively tests whether HER2 therapies may be safely administered in patients with reduced LV function in the setting of ongoing cardiac treatment and monitoring. Methods: Eligibility criteria: stage I-IV HER2 positive BC candidates for non-lapatinib therapy; LV ejection fraction (LVEF) ≥40% and < 50% and no symptoms of heart failure (HF). All patients had cardiology visits and echocardiograms at baseline, during treatment and 6 months after treatment, and received beta blockers (BB) and ACE inhibitors (ACEi) unless contraindicated. Primary endpoint was completion of planned oncologic HER2 therapy without development of a cardiac event (CE), defined as HF symptoms or asymptomatic decline in LVEF ≥10% points from baseline and/or to LVEF ≤35%. Results: Of 31 enrolled patients, 30 were evaluabl...