Is severe mitral regurgitation serious?

The mitral valve belongs to a tissue on the ventricle side of our human body, but our mitral valve often has many problems, including severe mitral valve regurgitation. This situation can be caused by many reasons, and the consequences and side effects caused by this situation are also relatively serious. So is severe mitral valve regurgitation serious?

The main pathophysiological change of mitral regurgitation is that mitral regurgitation increases the left atrial load and left ventricular diastolic load. When the left ventricle contracts, blood flows from the left ventricle into the aorta and the left atrium with less resistance. The backflow volume flowing into the left atrium can reach more than 50% of the left ventricular output.

In addition to receiving blood returning from the pulmonary veins, the left atrium also receives blood refluxed from the left ventricle. Therefore, an increase in left atrial pressure can cause an increase in pressure in the pulmonary veins and pulmonary capillaries, leading to dilation and congestion. At the same time, the left ventricular diastolic volume load increases and the left ventricle enlarges. In acute mitral regurgitation, a large amount of blood suddenly flows back into the left atrium, causing a sharp increase in left atrium and pulmonary vein pressure, leading to acute pulmonary edema.

The clinical diagnosis is mainly based on the typical blowing-like systolic murmur in the apical area and enlargement of the left atrium and left ventricle. Echocardiography can confirm the diagnosis.

The murmur of mitral regurgitation should be differentiated from the apical systolic murmur of:

1. Relative mitral regurgitation

It can occur in hypertensive heart disease, aortic valve insufficiency or myocarditis caused by various reasons, dilated cardiomyopathy, anemic heart disease, etc. Due to the significant enlargement of the left ventricle or mitral valve ring, the mitral valve is relatively incomplete and a systolic murmur occurs in the apical area.

2. Functional apical systolic murmur

About half of normal children and adolescents can hear a systolic murmur in the precordial area, which is loudness ranging from 1 to 2/6, short, soft in nature, does not mask the first heart sound, and does not cause enlargement of the atria and ventricles. It can also be seen in high-dynamic circulatory states such as fever, anemia, and hyperthyroidism. The murmur will disappear once the cause is eliminated.

3. Ventricular septal defect

A rough holosystolic murmur can be heard between the 3rd and 4th intercostal spaces on the left side of the sternum, often accompanied by a systolic thrill. The murmur is transmitted to the apex area, and the apex beat appears to be lifted. Electrocardiogram and X-ray examination showed enlargement of the left and right ventricles. Echocardiography showed a continuous interruption of the ventricular septum, and echocardiography could confirm the presence of left-to-right shunt at the ventricular level.

(IV) Tricuspid regurgitation

A localized, blowing-like, total systolic murmur is heard at the lower left edge of the sternum. The murmur increases during inspiration due to increased venous return and decreases during exhalation. In pulmonary hypertension, the pulmonary valve second heart sound is hyperactive and the jugular venous V wave is enlarged. The liver may pulsate and swell. Electrocardiogram and X-ray examination showed right ventricular hypertrophy. Echocardiography can confirm the diagnosis.

5. Aortic valve stenosis

A loud, rough systolic murmur may be heard in the aortic valve area at the base of the heart or in the apex, traveling toward the neck and accompanied by a systolic thrill. There may be an early systolic click and the apex beat may appear to be lifted. Electrocardiogram and X-ray examinations showed left ventricular hypertrophy and enlargement. Echocardiography can confirm the diagnosis.