Background: Anthracycline related cardiac toxicity (CT) is a concern in treating women with breast cancer. The prevalence of heart failure (HF) affects 2% of the population, less so in women. Patients receiving anthracycline based therapy (ABT) have a dose-dependent risk of reduction in ejection fraction. Recent work by Dr. Verma suggests that BRCA-deficient mice manifest increased levels of cardiac failure. We sought to explore the risk for CT and evaluate the association between ABT and HF in female BRCA mutation carriers. Methods: An online survey was developed to collect information about breast cancer treatment (including HF) in BRCA mutation carriers through the national BRCA patient advocacy organization FORCE via their 2011 conference and their website as well as the Moffitt-based Inherited Cancer Registry (ICARE). The prevalence of CT and HF was calculated in both BRCA 1 and 2 breast cancer patients and compared to general population risks. Data from those that received ABT was compared to published HF rates from ABT. Results: Our sample included 227 BRCA1 carriers and 164 BRCA2 carriers in whom 6.4% reported cardiac toxicity (i.e., either HF and/or CT). This included similar proportions in BRCA1 vs BRCA2 carriers (i.e., 6.6% and 6.1%, respectively). These proportions are significantly higher than the published rate of 2% (all p-values < 0.001). Specifically regarding ABT, 112 mutation carriers had doxorubicin (Adriamycin) for treatment of whom 8% reported HF, similar to the 11 who had Epirubicin (11 patients), of whom 9% reported HF. Conclusions: Our data suggests that BRCA mutation carriers may have an increased risk of CT compared to the general population. In particular, women with BRCA mutations treated with ABT also appear to have a higher risk of developing CT and/or HF. This exploratory study provides the basis upon which larger retrospective and prospective studies are currently being planned. The high percentage of CT observed in this study requires confirmation as they could inform recommendation for cardiac screening and review of the current standard for ABT use in this population.