This study evaluates the cost-effectiveness of the MAR-HF-Titration telemedicine programme, implemented at Hospital del Mar for patients with heart failure with reduced ejection fraction (HFrEF). A pre-post retrospective cost-effectiveness analysis was conducted using data from 208 patients enrolled between 2021 and 2023. Effectiveness was estimated by constructing individual pre- and post-intervention QALYs based on literature-derived utility values. Cost data were obtained from hospital administrative records at the patient level. Paired t-tests were performed, and costs and QALYs were modelled using gamma and beta distributions for probabilistic sensitivity analysis. A sensitivity analysis excluding newly diagnosed patients was also conducted. The programme was associated with a 52% reduction in total healthcare costs (€4,771.79 per patient), mainly driven by a reduction of the heart failure-related intervention costs, which accounted for 88% of total costs and decreased by 58% in the post-intervention period (€4,384.97 per patient). This reduction was also associated with a substantial decrease in length of stay during the post-intervention period, with a 76.63% reduction in total hospitalisations and an 82.34% reduction in hospitalisations related to heart failure. The effectiveness analysis showed an increase of 0.0298 QALYs per patient during the six-month intervention period. Similar outcomes were observed for non-newly diagnosed patients.