Background <p>This study aimed to assess the effectiveness of an interactive avatar application in enhancing self-care behaviors and improving recognition and response to heart attack symptoms among patients with Acute Coronary Syndrome (ACS).</p> Methods <p>A non-blinded, two-arm, randomized controlled trial was conducted with 78 ACS patients randomly allocated to either an intervention group or a control group. The control group received conventional education, while the intervention group received conventional education supplemented with training via an interactive avatar application. The application provided guidance on self-care practices, recognition of heart attack symptoms, and appropriate responses. Data were collected at baseline, 1 month, and 3 months post-discharge using demographic questionnaires, the Self-Care of Coronary Heart Disease Inventory, and the ACS Response Index. Statistical analyses included chi-square tests, independent samples t-tests, and Mann-Whitney U tests.</p> Results <p>At the 3-month follow-up, participants in the intervention group exhibited significantly higher scores on both the Self-Care of Coronary Heart Disease Inventory and ACS Response Index compared to the control group (<i>P</i> &lt; 0.05). Furthermore, during the 3-month follow-up period, all patients in the intervention group (100%) ceased activity and took sublingual nitroglycerin upon experiencing heart attack symptoms, compared to 80% in the control group.</p> Conclusions <p>The interactive avatar application proved effective in improving knowledge, attitudes, beliefs, and self-care behaviors among ACS patients. This innovative educational tool holds promise for enhancing patient outcomes in ACS management.</p> Trial registration <p> <?tk 2?>This study was registered at the Iranian Registration Clinical Trial Center (Code: IRCT20220920056001N1, Date: 2023-01-03).</p>