Abstract The association between the dissemination of scientific articles on Twitter and online visibility (as assessed by the Altmetric Score) is still controversial, and the impact on citation rates has never been rigorously addressed for cardiovascular medicine journals using a randomized design. The ESC Journals Study randomized 695 papers published in the ESC Journal Family (March 2018–May 2019) for promotion on Twitter or to a control arm (with no active tweeting from ESC channels) and aimed to assess whether Twitter promotion was associated with an increase in citation rates (primary endpoint) and of the Altmetric Score. This is the final analysis including 694 articles (one paper excluded due to retraction). After a median follow-up of 994 days (interquartile range: 936–1063 days), Twitter promotion of articles was associated with a 1.12 (95% confidence interval: 1.08–1.15) higher rate of citations, and this effect was independent of the type of article. Altmetric Attention Score and number of users tweeting were positive predictors for the number of citations. A social media strategy of Twitter promotion for cardiovascular medicine papers seems to be associated with increased online visibility and higher numbers of citations.