[Correction of mitral valve insufficiency in the incomplete form of atrioventricular canal]. / Korrektsiia nedostatochnosti mitral'nogo klapana pri nepol'noi forme atrioventriculiarnogo kanala.

Correction of the incomplete atrioventricular canal is considered to be a routine operation leading to mortality no more than 5%. Significant insufficiency of the atrioventricular (AV) valve worsens prognosis and increases mortality up to 30%. From 1989 to 1999 the Research Center of Cardiovascular Surgery performed 151 operations for this defect in patients aged 3 months to 50 years, which showed general mortality rates of 8.6%. The latter were largely related to the baseline insufficiency of the left AV-ostium, to the patientsT age of patients and the year of an operation. A combination of reparative valvuloplasties permits one to restore obturative mitral function more completely and to improve the outcomes of defect correction. Significant insufficiency of the AV-valve (over ++) is a risk factor of its preservation after surgery and may lead to death. Consideration of adequate indications for primary valve prosthesis may substantially reduce mortality rates.

[Embryologic and pathogenetic aspects of the common atrioventricular canal development]. / Embriologicheskie i patogeneticheskie aspekty razvitiia obshchego atrioventrikuliarnogo kanala.

Atrioventricular canal (AVC) is an inherited defect the embryological basis of which is deficiency of the affluent part of the interventricular septum (IVS). Folds of the atrioventricular (AV) valves are formed from the myocardium and not from the endocardial thickening but much later than the IVS formation. Under the conditions of the affluent part of IVS the mode of connection of the anterior fold of the left AV valve creates the narrowing of the left ventricular effluent part. Endocardial thickenings play a role of a glue fixing corresponding structural components of AV valves and primary heart partitions. The degree of sticking together determines great variants of the defect anatomy. Important deficiency of the affluent part of IVS is possible this making the function difficult due to space change of the endocardial thickenings. The common valve ring with freely floating bridge-like folds is frequently revealed in such case. The notion "deficiency of the endocardial thickenings" has the only manifestation as an isolated splitting of the anterior fold of the mitral valve and exhibits main features of AVC.

[Effects of the Blalock-Taussig operation on the development of the pulmonary artery in patients with tetralogy of Fallot]. / Vliianie operatsii Bleloka--Taussiga na razvitie legochnoi arterii u bol'nykh s tetradoi Fallo.

The effect of the Blalock-Taussig operation on the growth of the pulmonary arteries (PA) in infants with tetralogy of Fallot (TF) was studied in late-term periods. Thirty-eight patients were examined, angiography and study of hemodynamics were conducted 31 to 144 months after the Blalock-Taussig operation. The obtained data provide evidence that as the result of the operation all segments of the hypoplastic PA grew to such a size that radical correction of the anomaly could be accomplished. In patients with an initially normal size of the PA growth of the vessel was not encountered. Iatrogenic complications and deformities of the PA occurred in 13.2% of cases. These complications developed most frequently (7.9%) in patients in whom the anastomosis was established in the first year of life. The degree of severity of the infundibular stenosis grew in all patients. Severe obstruction of outflow from the right ventricle developed in 10.5% of patients; in 7.9% of children it was completely obstructed. In view of that prolonged delay of the second stage of surgical treatment is inexpedient.