RESUMO
"Four in one" is a research idea of identifying the classic prescriptions from the following four dimensions： "nature， location， tendency， and syndrome". The multi-dimensional analysis of the mechanism of classic prescription Zhigancao Tang in treating coronary heart disease helps to understand the syndrome differentiation and treatment thoughts of ZHANG Zhong-jing. The coronary heart disease results from deficiency. The efficacy of Zhigancao Tang in treating coronary heart disease can be elucidated from the "nature，location，tendency， and syndrome". In terms of nature， Zhigancao Tang is pungent and sweet in flavor and warm in property， with the sweet responsible for tonifying deficiency， the pungent for dispersing Yang， resolving Yin， and eliminating surplus pathogen， and the warm for moving Yangqi， nourishing blood， and promoting blood circulation. In terms of location， Zhigancao Tang mainly acts on vessels for restoring the normal circulation of blood in the vessels and improving coronary artery stenosis and the resulting ischemia and anoxia. In terms of tendency， Zhigancao Tang tends to affect the upper and inner parts of the body to tonify deficiency in Zangfu organs， promote fluid production， nourish nutrient blood， and dissipate cold simultaneously， thus alleviating chest impediment. In terms of syndrome， Zhigancao Tang is applicable to fluid exhaustion with blood dryness and Yin-yang-qi-blood deficiency syndrome， manifested as regularly or irregularly intermittent pulse and severe palpitation. Zhigancao Tang has been widely used for the treatment of over 70 diseases classified into 10 systems， especially the cardiovascular diseases， in traditional Chinese medicine （TCM） and western medicine. As the “one” of “four in one”， Zhigancao Tang is composed of multiple Chinese herbs and its therapeutic effect is superior to the sum of its parts. It ameliorates the coronary heart disease by resisting inflammation， protecting against ischemia-reperfusion injury， adjusting the ion channels of myocardial cells， and participating in atrial remodeling and hematopoiesis. Its mechanism and clinical efficacy in the treatment of coronary heart disease have been verified by clinical and experimental studies. The utilization of the thought of "four in one" to analyze classical prescriptions enables the combination of prescriptions with syndromes， which is of great significance to the clinical application and modern development of classical prescriptions.