Cardiogenic respiratory distress is defined as cardiogenic dyspnea caused by factors such as increased hydrostatic pressure and is commonly associated with cardiogenic pulmonary edema due to left heart insufficiency, which in turn leads to respiratory failure. Cardiogenic dyspnea is mainly caused by left and/or right heart failure, and the two occur by different mechanisms, with dyspnea due to left heart failure being more severe. So, what tests should be done for patients with cardiogenic respiratory distress? The following is a brief introduction: 1. ECG: In each cardiac cycle, the heart is excited by the pacing point, atria, and ventricles one after another, accompanied by bioelectric changes, and the graphs of various forms of potential changes are elicited from the body surface through the electrocardiographic tracer is called electrocardiogram (ECG for short). ECG is an objective indicator of the process of occurrence, propagation and recovery of cardiac excitation. ECG is an important tool to help determine whether the electrical activity of the heart is normal, and is the earliest, most commonly used and most basic diagnostic method in the diagnosis of coronary heart disease. 3.Doppler echocardiography: There are many red blood cells within the blood, which can reflect and scatter the ultrasound and can be considered as a tiny sound source. The probe is placed in the rib cage without moving and emits ultrasound. When red blood cells flow in the heart or large blood vessels, the sound frequency scattered by the red blood cells changes. As the red blood cells move toward the probe, the reflected sound frequency increases, and vice versa, decreases. This difference in sound frequency between the red blood cells and the probe in relative motion is called the Doppler shift. It shows the speed, direction and nature of the blood flow.