Additional methods of examination

X-ray examination: smoothed of the left border due to protrusion of the left atrium auricle, moderate enlarging of the pulmonary trunk, protrusion of the left low arch, narrowing of the retrocardial space in the second oblique position, declining of the esophagus on the radius, signs of pulmonary venous hypertension.

ECG: signs of hypertrophy of the left atrium and left ventricle.

Phonocardiogram taken at the apex shows diminished amplitudes of the first sound; the amplitude of the second sound over the pulmonary artery increases compared with that over the aorta; decreasing systole murmur at the heart apex it synchronous with the first heart sound.

Echo-CG: dilatation of the left parts of heart, excursion of the atrioventricular partition and back wall of the left ventricle, different direction of the diastolic motion of mitral valve, unclosing them during systole. Four degrees of mitral regurgitation are distinguished (from 2 up to 5 cm and above).

Mitral stenosis

Mitral stenosis develops due to narrowing of left atrioventricular orifice.

Etiology

- Rheumatic heart disease;

- Bacterial (infectious) endocarditis.

Disorders of hemodynamics

Disorders of hemodynamics: due to pathological process, the adhesion of the mitral cusps, it consolidation, thickening and shortening narrow the left atrioventricular orifice. In patient with mitral stenosis orifice becomes 1.5 sm² and less instead of normal 4-6 sm². Narrowing of an orifice is a mechanical obstacle for a flow of blood from the left atrium to the left ventricle during diastole. The part of blood remains in the left atrium. Besides blood from pulmonary veins comes into the left atrium. In the left atrium the volume of blood is increased (in norm 50-60 ml, at narrowing 100-2000 ml), pressure raises (in norm - 5-7 mm Hg, at narrowing - 20-25 mm Hg). So the left atrium hypertrophies. However the muscle of a hypertrophied left atrium weak, therefore its contractile function reduces soon. It leads to dilation of the left atrium and increasing of venous pressure in pulmonary veins and capillaries. Increased pressure elevates in the pulmonary veins leads to irritation of baroreceptors, and causes reflex contraction of the arterioles in the lesser circulation (Kitaev's reflex), so pressure in the pulmonary trunk considerably rises, so called pulmonary hypertention. Pulmonary hypertension leads to a hypertrophy of the right ventricle, and subsequently and to its dilation. The left ventricle receives less blood in diastole, its size a little decreases and diastolic dysfunction develops.

Clinical features

The specific complaints of the patients with mitral stenosis: exertional and nocturnal dyspnea, cough, palpitation, pain in the heart. Symptoms secondary to arterial/venous emboli are hemoptysis, chest pain. Symptoms of diminished cardiac output are fatigue, tiredness.

Objective examination. In general inspection patient looks younger his age, the mitral face is observed. The characteristic of face: the cyanotic blush on the cheecks.

Examination of the respiratory system reveals the congestion in lesser circulation - moist rales in low lobes of lungs.

Examination of the cardiovascular system In inspection of heart region the spread pulsation in the III-IV intercostals space along left edge of sternum with synchronous pulsation in the epigastric region are detected. During palpation apex beat is of normal location, area, height and strength. Cat's purr symptom is characteristic for mitral stenosis. Diastolic thrill is palpated at the apex.

In percussion relative cardiac dullness is displaced to the right and upward, protrusion of the upper part of the left contour, indistinct waist of the heart, increasing of absolute cardiac dullness area.

In auscultation the first heart sound at the apex becomes loud and snapping, because the left ventricle receives little amount of blood and fast closing of fibrous cusps of the mitral valve. An additional sound due to the opening of the mitral valve, which would be explained by sclerosed and connected among themselves cusps. The loud first heart sound, second sound with the sound of opening of the mitral valve give a specific melody of mitral stenosis so called triple rhythm at the apex. The second sound becomes accentuated and splitted over pulmonary artery. At some patients with mitral stenosis cardiac rhythm is irregular, because mitral stenosis is often complicated with atrial fibrillation.

Diastolic murmur at the apex is sign of the mitral stenosis because the orifice from the left atrium to the ventricle during diastole is narrowed. This murmur can be heard to follow the mitral valve opening sound in early diastole (protodiastolic murmur - noise of filling) because the velocity of the flow in early diastole is higher due to the decreased pressure difference in the atrium and the ventricle. The murmur can be heard at the end of diastole, immediately before systole (presistolic). It arises during acceleration of the blood flow at the end of ventricular diastole.

Pulse on the radial arteries may be asymmetrical (p. differens) because the left subclavia artery is compressed by considerable hypertrophy of the left atrium. Blood pressure usually remains normal.

Complications of mitral stenosis: atrial fibrillation, flutter, arterial or venous emboli with massive pulmonary, cerebral, peripheral thromboembolism, acute pulmonary edema, chronic left atrial heart failure, right ventricle heart failure.