VEGFB and cardiac hypertrophy: While VEGFB demonstrates its ability in rescue cardiac function, it concurrently triggers cardiac hypertrophy, a finding previously observed in young adult and diseased mice.20,23,36 To assess whether VEGFB induces physiological or pathological cardiac hypertrophy in aged mice, we investigated the cardiomyocyte length-to-width ratio, which reflects a suitable measure to discriminate between physiological and pathological hypertrophy.