Evaluating cardiovascular risk factors in breast cancer survivors: The role of echocardiography and cardiopulmonary exercise testing in the Munich Cardio-Oncology-Exercise retrospective Registry

Background: Breast cancer survivors (BCS) have an increased risk of developing cardiovascular disease risk factors (CVDRF). However, the role of cardiopulmonary fitness, echocardiography and treatment regimen e.g. anthracycline, HER2-targeted therapy (AC/H) or endocrine therapy (ET) are uncertain. Methods: This single-center, retrospective study included BCS without visceral metastases, who had been treated with either AC/H or ET and assessed by echocardiography, cardio-pulmonary exercise testing (CPET) and the H₂FPEF score at baseline. We included BCS with a left ventricular ejection fraction ≥50 % and absence of CVDRF at baseline. The primary outcome was the incidence of CVDRF. Results: A total of 112 BCS were included (mean age of 54.6 ± 9.9 years, BC stage I-III). After a median follow-up of 21 months new-onset arterial hypertension was the most common CVDRF observed (n = 17). New onset hypertension was related to higher baseline resting systolic blood pressure (127.4 ± 9.2 mmHg vs. 117.3 ± 13.1 mmHg, p = 0.002) and H₂FPEF scores (1.2 ± 0.8 vs. 0.8 ± 1.1, p = 0.043). Echocardiographic and CPET findings associated with new-onset arterial hypertension included greater left ventricular mass index (77.3 ± 24.2 g/m² vs. 65.6 ± 15.5 g/m², p = 0.007), higher peak systolic blood pressure (193.1 ± 19.5 mmHg vs. 173.3 ± 21.2 mmHg, p = 0.017) and ventilatory power (6.4 ± 1.3 mmHg vs. 5.7 ± 1.2 mmHg, p = 0.022). Treatment regimen had no influence on the development of CVDRF. Conclusions: The most common CVDRF among BCS is hypertension, underscoring the importance of monitoring this outcome irrespective of breast cancer treatment regimens. The H₂FPEF score, CPET and echocardiography may help identify BCS at risk of developing hypertension. Strain and biomarkers were not available, impeding detection of cardiotoxicity.