ObjectiveThrough multimodal research methods including medication rule mining， network pharmacology， molecular docking and dynamics simulation， and in vivo animal experiments， this study aims to speculate and verify the core composition （Ginseng Radix et Rhizoma Rubra-Salviae Miltiorrhizae Radix et Rhizoma-Notoginseng Radix et Rhizoma） and efficacy （Qi-invigorating and blood-activating） of the drug combination in Yitangkang Compound for improving diabetic cardiomyopathy （DCM）， investigate the interaction relationship and binding strength between core active ingredients of the drug combination and key signaling pathway targets， and further explore the mechanism by which the Qi-invigorating and blood-activating drug combination regulates the calcium signaling pathway to improve cardiac function in DCM rats.MethodsThe Ancient and Modern Medical Cases Cloud Platform was used to construct a DCM prescription database， and the "Analysis Method" module of the platform was applied to mine and summarize medication rules， thereby determining the core composition of the Qi-invigorating and blood-activating drug combination in Yitangkang. Drug-active ingredient-signaling pathway-core target-disease analysis and visualization were conducted by combining network pharmacology with the Traditional Chinese Medicine System Pharmacology Platform （TCMSP） database， Swiss Target Prediction platform， Gene Cards database， Metascape database， Cytoscape software， etc. Then， molecular docking was performed via the CB-Dock2 platform， and molecular dynamics simulation of the high-binding-strength docking complexes was carried out by Gromacs software. Finally， in vivo animal experiments were carried out. Twenty-eight Sprague Dawley （SD） rats meeting the research criteria were divided into a normal group， a model group， a drug combination group （3.3 g·kg^-1）， and a Yitangkang group （20 g·kg^-1）. A type 2 diabetes mellitus （T2DM） rat model was established by high-fat diet feeding combined with intraperitoneal injection of streptozotocin （STZ）， followed by continuous feeding for eight weeks until the DCM model was successfully established. During this period， the traditional Chinese medicine （TCM） compound and drug combination were administered for prevention and treatment intervention. Meanwhile， changes in blood glucose， body weight， and heart index of each group were monitored. Cardiac function was assessed by echocardiography， and electrophysiological signals were detected by an electrocardiogram. The heart tissue was observed for pathological changes by hematoxylin-eosin （HE） and Masson staining， and the expression of L-type calcium channel （CACNA1C）， calmodulin （CALM1）， calcium/calmodulin-dependent protein kinase Ⅱδ （CAMK2D）， and neuronal nitric oxide synthase （NOS1） proteins in the calcium signaling pathway of myocardial tissue was detected by Western blot.ResultsIn 62 DCM prescriptions， Ginseng Radix et Rhizoma Rubra， Salviae Miltiorrhizae Radix et Rhizoma， and Notoginseng Radix et Rhizoma were used most frequently. Their meridian tropism mainly involved the spleen， heart， and lung， and their sweet and warm properties were prominent. The drugs for tonifying or blood-activating and stasis-resolving ranked top. In association rule analysis， （Ginseng Radix et Rhizoma Rubra， Salviae Miltiorrhizae Radix et Rhizoma）-Notoginseng Radix et Rhizoma had the highest lift. Network pharmacology obtained 75 active ingredients of the drug combination， 714 drug combination action targets， 2 702 disease targets， and 286 intersection targets. Protein-protein interaction （PPI） network predicted nine interaction component–targets （nine active ingredients and four calcium signaling pathway target genes）. Molecular docking showed the four complexes with the lowest binding energy were 2f3z-ginsenoside Re， 1cll-quercetin， 9blh-（6S）-6-（hydroxymethyl）-1，6-dimethyl-8，9-dihydro-7H-naphtho［8，7-g］benzofuran-10，11-dione， and 5vv0-miltionone Ⅱ. Dynamics simulation showed the CALM1-quercetin complex had the strongest binding affinity. The animal experiment results revealed that compared with the normal group， the model group showed significant changes in blood glucose， body weight， myocardial tissue morphology， heart index， cardiac function， electrophysiological indexes， and the expression levels of CACNA1C， CALM1， CAMK2D， and NOS1 proteins （P<0.05， P<0.01）. Compared with the model group， the Yitangkang group had a certain improvement effect on the above indexes （P<0.05， P<0.01）. Compared with the Yitangkang group， the drug combination group showed no significant difference in improving myocardial tissue morphology， heart index， cardiac function， electrophysiological indexes， and the expression of CACNA1C， CALM1， CAMK2D， and NOS1 proteins， except for blood glucose and body weight.ConclusionGinseng Radix et Rhizoma Rubra， Salviae Miltiorrhizae Radix et Rhizoma， and Notoginseng Radix et Rhizoma are the core Qi-invigorating and blood-activating drug combination in Yitangkang Compound. They have a good preventive and therapeutic effect on STZ-induced DCM in rats， and their mechanism of action may be related to the regulation of the calcium signaling pathway.

diabetic cardiomyopathy;Yitangkang Compound;Ginseng Radix et Rhizoma Rubra-Salviae Miltiorrhizae Radix et Rhizoma-Notoginseng Radix et Rhizoma;medication rule mining;network pharmacology;molecular docking and dynamics simulation;calcium signaling pathway