Adverse Vascular Functional and Structural Changes Secondary to Breast Cancer and its Treatments with Adjuvant Therapy: a Systematic Review

Cardiovascular disease (CVD) is a leading cause of death in people with breast cancer (BCa). Vascular dysfunction and adverse arterial remodelling are important contributors to the development of CVD. Antineoplastic (chemotherapy, targeted therapies, hormonal therapies) and radiation therapies may lead to adverse vascular structural and functional remodelling in BCa survivors. This systematic review will summarize the current evidence on the effects of breast cancer and its treatments on vascular function and structure in BCa survivors. The MEDLINE, PsycINFO, CINAHL, EMBASE and EBM databases were searched. The PICO-guided search strategy included (1) Population: human studies of BCa survivors; (2) Intervention: chemotherapy, targeted therapies, radiation and hormonal therapies; (3) Comparison: healthy controls, multiple time points or BCa survivors with naive treatment status; (4) Outcomes: predefined vascular structure and function measures. Sixteen studies were identified involving participants treated with hormonal therapies, radiation, targeted therapies, anthracyclines and other chemotherapies. With the exception of tamoxifen, therapies were consistently associated with maladaptive changes in vascular structure (increases in arterial stiffness and increases in intima-media thickness) and function (endothelial dependant brachial-artery flow-mediated dilation) up to 12 months post initiating therapy. Long-term changes (>12 months) in vascular health remains equivocal, with the exception of radiation which lead to long-term deficits in vascular structure. Cytotoxic chemotherapy, targeted therapies and radiation elicit negative changes in vascular health, which may contribute to increased CVD risk in BCa survivors. Closer cardiac monitoring and optimizing cardiac risk factors through cardiac (exercise) rehabilitation is suggested to offset the CVD burden following a BCa diagnosis.