Pulmonary congestion (pulmonarycongestion) is a localized blood pooling in the blood vessels of the lungs, usually caused by left heart failure, in which elevated pressure in the left heart cavity obstructs pulmonary venous return, resulting in pulmonary congestion. 1.Electrocardiogram: It can reveal information about previous myocardial infarction, left ventricular hypertrophy, extensive myocardial damage and arrhythmia. 2. Chest X-ray: it can show information of enlarged heart, pulmonary bruise, pulmonary edema and previous lung disease. 3.Echocardiography (1) Diagnose pericardial, myocardial or valvular diseases. (2) Distinguish diastolic insufficiency from systolic insufficiency. (3) Quantify or characterize atrial and ventricular internal diameters, cardiac geometry, ventricular wall thickness, ventricular wall motion, as well as pericardial, valvular, and vascular structures, quantify the degree of valvular stenosis and closure insufficiency, and measure the left ventricular ejection fraction (LVEF), and left ventricular end-diastolic and end-systolic volumes (LVEDV, LVESV). (4) Estimate pulmonary artery pressure. (5) Provide objective indicators for evaluating treatment effects. 4. Heart failure markers: B-type natriuretic peptide (BNP) and N-terminal B-type natriuretic peptide proximate (NT-proBNP) are markers for patients with heart failure, and the value can be decreased after improvement of the symptoms by treatment.