Isolated pulmonary stenosis accounts for 1.6–9% of all congenital heart defects.
Anatomical variants of the defect are reduced to narrowing the path of outflow from the right ventricle of the heart. Distinguish valve stenosis (fusion of valve commissures); infundibular ( subvalvular ) stenosis due to the presence of a muscle diaphragm with a small opening or muscle hypertrophy of the exit tract of the right ventricle; supravalvular stenosis of the pulmonary trunk and branches of the pulmonary artery ( coarctation ). Sometimes there are combinations of the above variants of the anomaly.
The hemodynamics of the disease boils down to systolic overload of the right ventricle, which increases with increasing degree of stenosis. In this case, there is a restriction of pulmonary blood flow, which determines the degree of cyanosis. Compensation of the defect is supported by hypertrophy of the right ventricle. Characteristically, dila – tation it usually does not happen. Thus, hypertrophic syndrome of the “small ventricle” develops. Due to the increase in the rate of its reductions, as a rule, due MOS is kept relatively long. Over time, ischemic contracture of the hypertrophied myocardium of the right ventricle develops and it ceases to cope with a high load. Decompensation sets in: cyanosis appears, venous pressure rises, hepatomegaly , peripheral edema develop and progress .
The clinic is determined by the severity of stenosis and the state of compensatory mechanisms. Clinical manifestations range from asymptomatic to severe forms (severe shortness of breath at the slightest exertion, anginal pain, cyanosis). Auscultation is characterized by gross systolic murmur with an epicenter in the second and third intercostal space on the left ( infundibular stenosis). In the late stages of the defect, cyanosis, venous hypertension (visible dilatation of the cervical veins), enlargement of the liver, and peripheral edema join.
Radiologically observed: a moderate increase in the right ventricle, narrow roots of the lungs, impoverishment of the pulmonary pattern. Valvular stenosis is characterized by suprastenotic expansion of the pulmonary artery due to hydrodynamic shock of a narrow stream of blood. On the ECG – a rightogram , signs of systolic overload of the right ventricle. FCG reveals a rhomboid systolic murmur in the pulmonary artery, a decrease in the amplitude of II tone in this zone. To determine the severity of stenosis and clarify indications, surgical treatment is resorted to sounding of the heart cavities. The main clinical criteria are the systolic pressure gradient between the right ventricle and the pulmonary artery, as well as the systolic pressure in the right ventricle. The latter criterion is more informative. It determines the clinical stages of the course of the disease: I – moderate stenosis (systolic pressure in the right ventricle below 60 mm Hg (8 kPa); II – severe stenosis (systolic pressure in the right ventricle 60 to 100 mm Hg (8 —13.3 kPa), III – severe stenosis (systolic pressure in the right ventricle is higher than 100 mmHg (13.3 kPa). With coarctation of the pulmonary trunk and its branches, angiopulmonography is most informative .
The remains of a hyaloid artery is an anomaly of development that occurs due to a violation of the reverse development of the hyaloid artery in the embryonic period. Usually found at a young age, with age, this artery resolves. The clinical picture and diagnosis. It manifests itself in the form of a strand (moorings) of the vitreous body, which goes from the optic disc to the lens. More often, the remains of an artery are detected in the anterior or posterior parts, and not along the entire length. In this case, the artery has the form of a corkscrew or rope, the end of which floats freely in the vitreous. Very rarely, the remains of the hyaloid artery are shrouded in a layer of connective tissue and can significantly impair vision.