轻型心肌梗塞,一般心排出量正常,不出现心衰;中度心肌梗塞,心排出量可不减少,但左室舒张末期压可轻或中度升高,出现呼吸困难等心衰症状,经适当休息和治疗,心功可逐渐恢复;重度心肌梗塞,常使左室舒张末期压明显升高,心排出量大减,患者几乎均难免出现肺郁血、肺水肿等左心衰竭 Light myocardial infarction, normal cardiac output is normal, no heart failure; moderate myocardial infarction, cardiac output may not reduce, but left ventricular end diastolic pressure may be mild or moderate increase, dyspnea and other heart failure symptoms, appropriate Rest and treatment, heart function can be gradually restored; severe myocardial infarction, often left ventricular end-diastolic pressure was significantly increased cardiac output significantly reduced, almost all of patients almost inevitable pulmonary depression, pulmonary edema and other left heart failure