Acute left heart insufficiency is also known as acute left heart failure, and such a patient should be placed in a sitting position with legs down to reduce venous return blood flow, as acute left heart failure, hypoxia, and high levels of dyspnea can lead to fatal risks. Immediate symptomatic relief is essential, so sitting can reduce the volume of blood returning to the heart, reduce the burden on the heart, and provide oxygen, high-flow nasal cannula oxygen, and in severe cases, consider oxygen delivery by face mask ventilator. Morphine injection can reduce the burden on the patient’s heart, and can play a sedative, reduce the agitation brought about by the increased burden on the heart, and rapid diuresis, reduce pulmonary edema, the application of vasodilators, including sodium nitroprusside or nitroglycerin, and recombinant human brain natriuretic peptide, positive inotropic drugs, including dopamine, dopa-phenol butyramide, milrinone, these drugs can increase the myocardial contraction force, increase the output of the heart. Digitalis drugs have cardiotonic effects, but they cannot be used in acute left heart failure caused by acute infarction within 24 h. Pulmonary edema caused by mitral stenosis is also ineffective, and if conditions permit, mechanical adjuvant therapy can be applied, such as IABP and temporary cardiopulmonary adjuvant systems.