Patient perspectives on cardioprotective medication during breast cancer treatment

Background: Cardiotoxicity remains a key concern of HER2-directed therapies, with no proven prevention strategies. The success of cardioprotective interventions will depend not only on efficacy, but on patient acceptability, an underexplored determinant of trial participation and clinical implementation. Objectives: To evaluate willingness to take cardioprotective medication and identify factors influencing decision-making among individuals with HER2-positive breast cancer. Methods: We conducted a cross-sectional online survey of adults with HER2-positive breast cancer in Australia and the United States. The survey assessed willingness, beliefs regarding benefits and risks, and treatment preferences. Multivariable logistic regression examined associations between clinical and demographic characteristics and willingness. Results: Among 74 respondents (Australia n=24; United States n=50), 74.3% reported being likely or very likely to take cardioprotective medication. Physician recommendation emerged as a dominant driver (79.1%). While most participants valued long-term cardiovascular health (72.9%), uncertainty regarding benefit was common (60.4%). Cancer-related outcomes were prioritized over cardiovascular outcomes. Participants demonstrated flexibility regarding treatment burden, including willingness to take multiple medications and continue therapy long term. No demographic or clinical predictors of willingness were identified. Perceived acceptability, appropriateness, and feasibility were consistently high. Conclusions: Willingness to adopt cardioprotective strategies is high but conditional, shaped by cancer priorities, clinician endorsement, and uncertainty regarding benefit. These findings highlight patient acceptability as a critical, and often overlooked, determinant of successful trial participation and downstream clinical implementation in cardio-oncology.