ZH-LF in isolated perfused Langendorff isolated heart perfusion system, the system is suitable for in vitro mammalian heart perfusion (langendorff's method) and in vitro determination of coronary flow (coronaryfilw.cf) of. Constant perfusion can be directly coupled peristaltic pump can be constant perfusion. Experimental procedure: A. preparation 37 ℃ KH solution (1.25 CaCl2,130 NaCl, 5.4 KCl, 11 glucose, 0.5 MgCl2,0.5 NaH2PO4 and 25 NaHCO3), KH solution to pass into the 95% O2-5% CO2 gas, buffer PH value of 7.4, and take part of the KH solution in the refrigerator, so that the temperature dropped to 4 ℃. B. Clean Langendorff pipes, each with a 1000ml before use distilled water, open water bath cycle, then KH solution to wash the entire pipeline system. C. Animals were anesthetized by intraperitoneal injection of sodium Rumi (100mg / kg), and to the hepatic vein injection 100IU heparin, carotid animals were sacrificed, while rapid separation of heart, into 4 ℃ KH solution, squeeze the net blood and weighed. D. The heart Langendorff perfusion system quickly fixed by retrograde aortic perfusion pressure to 85cmH2O catheters inserted through the pulmonary veins to the left atrium. E. after cardiac resuscitation, a balloon inserted into the left ventricle, the balloon and a pressure transducer connected to the computer records in left ventricular pressure, left ventricular internal diastolic pressure adjustment (LVEDP) between 4 ~ 10mmHg. To be left ventricular systolic pressure (LVESP) after stabilization and greater than 80mmHg, heart rate greater than 200 beats / min, can continue to experiment and record the electrocardiogram (ECG), aortic flow (AF), coronary flow (CF), left ventricular systolic end pressure (LVESP) and other indicators. F. ischemia-reperfusion solution: close perfusate, irrigation heart stopped after 45min, open perfusate reperfusion 90min (15min reperfusion via the pulmonary veins start to give some pressure assisted), while recording relevant indicators. G. After the end of the experiment, the entire piping system with distilled water to prevent KH liquid remaining in the pipeline.