Cardiac function and coronary plaque development following masculinizing gender‐affirming hormone therapy: A prospective cohort study

INTRODUCTION: Myocardial dysfunction and the presence of calcified and non-calcified coronary plaques are predictors of cardiovascular disease. Masculinizing gender-affirming hormone therapy may increase cardiovascular risk, highlighting the need for prospective studies to evaluate cardiovascular outcomes during gender-affirming hormone therapy. OBJECTIVES: To evaluate changes in cardiac morphology, systolic and diastolic function, and development of coronary plaques after masculinizing gender-affirming hormone therapy. METHODS: Prospective study including 47 transmasculine persons (gender-affirming hormone therapy-naïve, TransMTN, n = 15 and gender-affirming hormone therapy-ongoing, TransMTO, n = 32). Included persons were evaluated at study inclusion and after one year of masculinizing gender-affirming hormone therapy. At baseline, the median age of TransMTN was 22 years (interquartile range 19-28 years) and TransMTO 26 years (interquartile range 24-37 years) with a median gender-affirming hormone therapy duration of 4 years (interquartile range 2-5 years). Cardiac morphology including left ventricular wall thickness, volume, and mass, as well as left ventricular systolic and diastolic function was evaluated using echocardiography. Coronary artery calcifications and non-calcified coronary plaque were assessed using coronary computed tomography angiography. Paired and unpaired statistical analyses were performed within and between TransMTN and TransMTO groups. RESULTS: In TransMTN, diastolic function decreased during follow-up with decreased septal and lateral left ventricular relaxation (14-11 cm/s, p = 0. 04 and 18-15 cm/s, p = 0. 02, respectively). No significant changes were observed in cardiac morphology, systolic function, or formation of coronary artery calcifications and non-calcified coronary plaque in TransMTN or TransMTO groups. At baseline, left ventricular end-diastolic internal diameter was significantly higher in TransMTO compared to TransMTN, 4. 6 cm (interquartile range 4. 3-5. 0 cm) versus 4. 4 cm (interquartile range 4. 2-4. 6 cm), p < 0. 05. Other baseline cardiac outcomes were comparable between TransMTN and TransMTO. CONCLUSION: Diastolic function declined after the initiation of masculinizing gender-affirming hormone therapy and individuals on long-term masculinizing gender-affirming hormone therapy had larger left ventricular dimensions compared to individuals before gender-affirming hormone therapy initiation. Cardiac morphology, systolic function, and coronary plaque formation remained stable during masculinizing gender-affirming hormone therapy.