PubMed Health⌕ Search

Biomedical subjects

V I Shumakov

Publications and source records attributed to V I Shumakov.

At least 127 records · Page 7Linked to original sources
PubMed1978

[Comparative evaluation of membrane, bubble and foam-film oxygenators in artificial circulation during heart surgery].

Single-use membraneous oxygenators "Teflo" (TMO) and bubble oxygenator "Variflow" (VF-1) issued by "Travenol" firm were used on 30 patients in open-heart operations with extracorporal circulation. A comparative assessment of working, technical and functional performances of these devices against the foam-membraneous oxygenator (FMO) of "AIK-5m" apparatus proved the reliability, safety, feasibility and high effectiveness of the single-use oxygenating systems, membraneous oxygenator in particular, which is the most promising one for the use in extracorporal circulation.

Adolescent↗
PubMed1978

[Contractile reaction of the myocardium of patients with heart diseases to chemical scarification of cell membranes].

Strips of the myocardium from the auricula atria of patients suffering from mitral stenosis (MS) and septal defects of the heart (SDH) removed during the operation were treated with ethylenediaminetetraacetic acid (DETA)--3mM--to increase the cell membrane permeability (scarification). The mechanical response of the contractile proteins to the change in the Ca2+ was recorded in the ethylene-hexaaminetetraacetic acid (EHTA)--3mM--against the background of increased membrane permeability to the Ca-EHTA complex permitting to regulate Ca2+ concentration in myofibrillae from 10(-9) to 10(-4)M. As shown, with the same threshold concentrations (5.10(-8)M) and saturation concentrations (10(-4)M) of Ca2+ the strips from the patients with MS developed the maximal tension per cross section unit of the strip half as great as the preparations from patients with SDH, this indicating a possible affection of the contractile proteins in the hearts of patients with MS. The ratio between the tension amplitudes under conditions of a complete calcium activation of the contractile proteins and a single isometric contraction for the preparations obtained from the patients with MS was 8 to 10, and with SDH--from 4 to 5. It is supposed that this was the result of more pronounced changes in the apparatus of electromechanical conjugation of the myocardium of patients suffering from MS.

Calcium↗
PubMed1977

[Effect of adrenaline on the contractility of different portions of the myocardium of homeotherms].

The contractility of myocardial strips from the atrium and ventricle of rabbit heart had some differences in the parameters of single contraction, interval--tension relationship, and transitional process. These differences were eliminated by increasing the concentration of epinephrine in bath solution. Epinephrine changed the mode of time--force relation of contraction and induced appearance of extremum in all the parts of the heart. The linear relation between the force of atrium contraction and that of ventricle contraction (homochromity) during change of contraction frequency in normal solution, was shown. The homochromity of atrium and ventricle was broken by high epinphrine concentrations. The level of endogenous catecholamines which modulate the excitation--contraction relations, is believed to determine the differences in the physiological reactions of atrial and ventricular strips. The use of atrium of the heart as a transducer for management of artificial heart is proposed.

Animals↗
PubMed1976

[Myocardial ultrastructure in the presence of assisted circulation].

Experiments were conducted on dogs; a study was made of the influence of a method of assisted circulation--contrapulsation, on the myocardial ultrastructure. A sharp glycogen accumulation in the muscle cells of the heart, the presence of mitochondria with a marked osmophilic microgranular matrix, and also a high pinocytic activity of the capillary endothelial cells were revealed by electron microscopy. The data obtained pointed to the metabolic reconstruction in the myocardium, and primarily to the reduction of the energy level of the myocardial muscle cell function. The changes in the myocardial ultrastructure revealed apparently provided the positive therapeutic effect.

Animals↗