Heart Failure with Breast Cancer Chemotherapy: A Risk Worth Taking Seriously

Findings from a large database suggest that trastuzumab is associated with higher rates of HF or cardiomyopathy in clinical practice than it was in clinical trials.

The anthracyclines, often used in adjuvant chemotherapy for breast cancer, are known to cause potentially permanent left ventricular systolic dysfunction. Newer breast cancer therapies, including the monoclonal antibody trastuzumab, have also been implicated in incident cardiomyopathy. The clinical trials of trastuzumab that exposed this adverse effect were generally conducted in younger women and may substantially underestimate the risk in older women, who constitute a sizeable proportion of breast cancer patients receiving adjuvant chemotherapy.

Investigators used the Surveillance, Epidemiology, and End Results Medicare database to assemble a cohort of 45,537 women aged 67 to 94 (mean age, 76) with early-stage breast cancer and no recorded history of heart failure (HF). New-onset HF or cardiomyopathy was defined as a single inpatient claim or two outpatient claims more than 30 days apart after chemotherapy. Only about 2% of the cohort received trastuzumab, alone or with an anthracycline; an additional 12% received an anthracycline without trastuzumab. After multivariable adjustment, the 3-year incidence of HF or cardiomyopathy (per 100 patient-years) was 32.1 in the trastuzumab-only group, 41.9 in the trastuzumab–anthracycline group, and 20.2 in the anthracycline-only group, compared with 18.1 in patients receiving no adjuvant chemotherapy.

CITATION(S):

Chen J et al. Incidence of heart failure or cardiomyopathy after adjuvant trastuzumab therapy for breast cancer. J Am Coll Cardiol 2012 Dec 18; 60:2504.

Lenihan DJ. Progression of heart failure from AHA/ACC stage A to stage B or even C: Can we all agree we should try to prevent this from happening? J Am Coll Cardiol 2012 Dec 18; 60:2513.