Objective To observe the effects of dagliflozin combined with levosimendan on soluble growth-stimulated expressed gene 2 protein （sST2）， angiopoietin Ⅱ （Ang-Ⅱ） and cardiac function in elderly patients with heart failure after percutaneous coronary intervention （PCI）. Methods Eighty patients with acute myocardial infarction （AMI） admitted to the Department of Cardiology of the Affiliated Hospital of Jiangnan University from January 2021 to October 2023 were selected and divided into two groups using the lottery method. Both groups were treated with conventional therapy. The conventional group was treated with levosimendan， and the combination group with dagliflozin combined with levosimendan. Cardiac function indexes， sST2， amino-terminal brain natriuretic peptide precursor （NT-pro BNP）， renin-angiotensin-aldosterone system indexes， cardiac myosin-binding protein-C （cMyBP-C）， cardiac troponin I （cTnI）， myoglobin （MyO）， 6-minute walking distance， heart failure scoring system （Lee） score， and the Seattle Angina Scale （SAQ） score were compared between the two groups. The cumulative major adverse cardiovascular event （MACE） rate at 6-month follow-up was counted in both groups. Results The comparison of cardiac function indexes， sST2， NT-proBNP， cMyBP-C， cTnI， MyO， and renin-angiotensin-aldosterone system indexes before treatment between the two groups showed no statistical significance （P > 0.05）. Left ventricular ejection fraction （LVEF） of the two groups was higher than that before treatment， and the indexes of the renin-angiotensin-aldosterone system， end-systolic left intraventricular diameter （LVEDD）， sST2， NT-proBNP， end-diastolic left intraventricular diameter （LVESD）， cMyBP-C， cTnI， MyO， and left ventricular mass index （LVMI） were lower （P< 0.05）. LVEF was higher in the combination group than that in the conventional group after treatment， and the indexes of the renin-angiotensin-aldosterone system， sST2， cMyBP-C， LVEDD， NT-proBNP， LVESD， cTnI， MyO， and LVMI were lower than those in the conventional group （P < 0.05）. There was no statistically significant difference between the two groups in terms of 6-minute walking distance， Lee score， and SAQ score before treatment （P > 0.05）. The 6-minute walking distance and SAQ score after treatment in both groups were longer and higher than those before treatment， and the Lee score was lower （P < 0.05）. The 6-minute walking distance and SAQ score after treatment in the combination group were longer and higher， and Lee score was lower than those in the conventional group （P < 0.05）. The cumulative incidence of MACE at 6-month follow-up in the combination group was lower than that in the conventional group， and the difference was statistically significant （P < 0.05）. Two cases of gastrointestinal reactions were found in the conventional group， and one case of hypotension and three cases of gastrointestinal reactions in the combination group. Conclusion Dagliflozin combined with levosimendan improves cardiac function， modulates the renin-angiotensin-aldosterone system， and improves exercise tolerance and quality of life in patients with heart failure after PCI.