Rapamycin (RAPA) and related mTOR-inhibitors have been shown to enhance healthy aging in animal models (2–10) and to be generally safe and tolerable in older people (11–13). However, studies to assess their effects on specific age-related pathologies in humans are limited. Since improvements in cardiovascular function with RAPA treatment have been reported in preclinical studies (5, 9, 10, 14–17), we posited that RAPA could be...