Women at medium CV profile presented a trend with a consequent significant increase in hospitalizations for heart failure in the aromatase inhibitors group during the 5-year period of treatment (HR = 1.63 (1.21–2.20), p < 0.001) and thereafter (HR = 1.42 (1.12–1.81), p = 0.004). This evidence concerns the gene CYP19A1 and heart failure.