Objective: To explore the impact of optimized drug therapy after percutaneous coronary intervention (PCI) on cardiac function and quality of life in patients with coronary heart disease. Method: 244 patients with coronary heart disease admitted to our hospital from June 2023 to December 2024 were selected as the research subjects. Both groups of patients underwent PCI. The patients were divided into the control group and the observation group by random number table method, with 122 cases in each group. Both groups received PCI. The control group received conventional drug intervention after the operation. The observation group adopted postoperative optimized drug intervention. The cardiac functions [left ventricular ejection fraction (LVEF), left ventricular end-systolic diameter (LVESD), left ventricular end-diastolic diameter (LVEDD)], angina symptoms [Seattle Angina Questionnaire (SAQ)], quality of life (SF-36 score), and major adverse cardiovascular events (MACE) of the two groups were analyzed and compared. Results: After the intervention, the LVEF of both groups was significantly increased compared with that before the intervention, while the LVESD and LVEDD were significantly decreased. Moreover, the improvement amplitudes of various cardiac function indicators such as LVEF, LVESD, and LVEDD in the observation group were significantly greater than those in the control group (P < 0.05). After the intervention, the SAQ scores of angina pectoris stability, angina pectoris attack frequency, treatment satisfaction, and physical limitation in both groups were significantly higher than those before the intervention, and the SAQ scores of each dimension in the observation group were significantly higher than those in the control group (P < 0.05). After the intervention, the SF-36 scores of each dimension including physiological function, social function, physical pain and mental health in both groups were significantly improved compared with those before the intervention, and the SF-36 scores of each dimension in the observation group were significantly higher than those in the control group (P<0.05). The incidence of MACE in the observation group was significantly lower than that in the control group (P < 0.05). Conclusion: The implementation of optimized drug intervention after PCI can improve the cardiac function of patients with coronary heart disease, promote the relief of angina pectoris, enhance the quality of life, and reduce the incidence of MACE.