Normal value of left ventricular systolic function

Ordinary people should have a certain biological knowledge of the human heart. The human heart is mainly divided into the left ventricle and the right ventricle. Moreover, the functions of the left ventricle and the right ventricle are also different, but the left ventricle and the right ventricle are contracting all the time. When you find that there is a problem with your left ventricle, you can do a left ventricular systolic function test, but what is the normal value of the left ventricular systolic function test?

What are the indicators of left ventricular diastolic function?

Left ventricular diastole includes two phases: isovolumetric relaxation and filling. The latter is also divided into rapid filling phase, slow filling phase and left atrial contraction phase; it is a complex physiological process involving multiple factors, and there is currently no recognized indicator for comprehensive evaluation of left ventricular diastolic function.

(1) During the isovolumetric relaxation period, the main factor affecting the left ventricular diastolic function is the relaxation of the left ventricular myocardium. The indicators that can quantitatively reflect this performance mainly include: the maximum rate of decrease of left ventricular pressure (-dp/dt^) and the left ventricular relaxation time constant (T). The normal values ​​of these indicators are: dp/dt^: (243±34.8)~(389±100)kPa/s[ (1825±261) ~ (2922±750)mmHg/s]. Constant T:

(2) Among the indicators of the left ventricular filling phase, there is currently no indicator that can directly measure the relaxation and stiffness of the left ventricular myocardium. It can only reflect the filling changes of the left ventricle during diastole. When measuring, the influence of cardiac load status, heart rate and myocardial contractility should be excluded as much as possible. Commonly used indicators are: 1) Left ventricular isovolumetric relaxation time (IVRT): refers to the time required from the closure of the aortic valve to the opening of the mitral valve. Normal value: (69±12) ms for those under 40 years old, (76±13) m/s for those over 40 years old. (2) Maximum velocity of mitral blood flow in early diastole (EV): Normal value: (0.86±0.16) m/s.

Can people in their twenties also have left ventricular diastolic dysfunction?

Left ventricular diastolic dysfunction generally occurs in older people (over 60 years old), but in recent years, many young and middle-aged people have also been found to have left ventricular diastolic dysfunction during physical examinations. These people are under great work pressure and are prone to fatigue. According to investigation, the occurrence of left ventricular diastolic dysfunction in young and middle-aged people is closely related to factors such as lifestyle habits, work pressure, and high blood lipids.

Is the reduced left ventricular diastolic function serious? Is treatment necessary?

Many diseases can lead to reduced left ventricular diastolic function, the most common of which are hypertension, coronary heart disease and diabetes. Long-term hypertension leads to myocardial remodeling, left ventricular hypertrophy, and decreased diastolic function; long-term coronary heart disease leads to myocardial ischemia and hypoxia, myocardial remodeling, and decreased diastolic function; long-term hyperglycemia leads to myocardial metabolic disorders, causing myocardial fibrosis, and may also cause decreased diastolic function.

In addition to the decreased left ventricular diastolic function caused by the above-mentioned diseases, there is another situation that occurs in middle-aged and elderly people without obvious diseases. As people age, the relaxation function of the left ventricle decreases compared to when they were young, which manifests as a slight decrease in diastolic function on echocardiogram.

Whether decreased left ventricular diastolic function requires treatment depends mainly on the cause of the decreased diastolic function.

If it is caused by hypertension, it means that the blood pressure has been poorly controlled for a long time and has led to myocardial remodeling. At this time, it is necessary to actively lower blood pressure to control blood pressure to the standard, and give priority to antihypertensive drugs that can reverse left ventricular hypertrophy and improve myocardial diastolic function under the guidance of a doctor;

If it is caused by coronary heart disease, standard coronary heart disease medication should be adopted, and interventional treatment should be performed if necessary;

If it is caused by diabetes, blood sugar should be brought to the standard through diet management, drug treatment, etc.