Effectiveness of Bokeria-Boldyrev ACH Solution in Surgerical Treatment of Adult Patients with Obstructive Hypertrophic Cardiomyopathy.

The study examined effectiveness of pharmaco-cold cardioplegia employing solutions of enhanced buffer capacity during surgery of obstructive hypertrophic cardiomyopathy in adult patients (N=51) operated during 2013-2018. In group 1 (N=28), the cardioplegia was performed with HTK (Custodiol) solution, whereas in group 2 (N=23), it was carried out with Bokeria-Boldyrev ACH solution. The mean, minimum, and maximum ages in group 1 were 46, 21, and 64 years, respectively; in group 2 - 42, 14, and 70 years, respectively. In both groups, the patients were subjected to myoectomy of exit pathway in the left ventricle according to Bokeria-Morrow operation and annuloplasty of tricuspid valve accompanied by reconstructive surgery (or replacement) of mitral valve. Atrial fibrillation (if any) was suppressed with cryoablation (-60°Ð¡) of the openings of the right and left pulmonary veins. The surgery was carried out in hypothermic mode at 28°C. The significant intergroup differences were observed in the asystole latent period after the onset of antegrade or retrograde injection of cardioplegic solution. In group 1, the asystole latent periods determined after antegrade or retrograde injection were 53±7 or 170±30 sec, respectively; in group 2 - 32±6 and 97±11 sec (p<0.0001), respectively. The mean times of aortic cross-clumping in groups 1 and 2 were 66±8 and 64±6 min, respectively; the electromechanical action of the heart restored after aortic unclamping in 35±7 and 30±6 sec, respectively. The biochemical and clinical data revealed no significant intergroup differences. Overall, novel Bokeria-Boldyrev ACH cardioplegic solution secured effective protection of the myocardium against intraoperative ischemia in adult patients with obstructive hypertrophic cardiomyopathy and significantly decreased the asystole latent period.

Peculiarities of Histological Structure of Pulmonary Veins in Patients with Total Anomalous Pulmonary Venous Drainage as Morphological Substrates Relating to Formation of Postoperative Pulmonary Venous Obstruction.

The histological and immunohistochemical methods were employed to examine the peculiarities of histological structure of pulmonary veins and left atrium of the heart in norm and in various types of total anomalous drainage of pulmonary veins. In contrast to normal pulmonary vein covered with external multiple muscle layers (myocardial sleeve), such sleeve is absent in veins that have no connection with the left atrium irrespective of the type of the defect. In patients with total anomalous pulmonary venous drainage, the structure of left atrium was heterogeneous featuring either the presence or absence of inner angiomural lining in this atrium. The structural peculiarities are important for insight into etiology of the development of postoperative pulmonary venous obstruction in patients with total anomalous pulmonary venous drainage.

[CLOSING OF INTERVENTRICULAR SEPTUM DEFECT IN ONE-STEP AND STEPWISE SURGICAL TREATMENT IN PATIENTS WITH PULMONARY ATRESIA AND AORTO-PULMONARY COLLATERALS].

Pulmonary atresia with defect of interventricular septum and collateral pulmonary blood flow refers to complicated congenital malformation of the heart. Surgical treatment represents itself as very difficult task because of anatomical variability of this abnormality. The main problem of surgery is a definitive repair of the defect including correction of maldistributions of pulmonary arterial bed (unifocalization of pulmonary blood flow), reconstruction of outflow tract of the right ventricle and closing of interventricular septum defect. The performance of closing interventricular septum defect could be successful in patients with pulmonary atresia and collateral pulmonary blood flow in case of stepwise and one-step surgical treatment. The combination of maximal number of pulmonary segments and sufficient development of central pulmonary arteries facilitates to progress of assigned task. Patients with the level of pulmonary-arterial index more than 170 mm/m2 and integrity of pulmonary arterial bed, centralization of pulmonary segments (minimum 15) could be considered as a candidate for definite repair of the defect.

Markers of myocardial damage in children of the first year of life with congenital heart disease in the early period after surgery with cardioplegic anoxia.

We measured the level of cardiac markers (high-sensitivity troponin T and MB fraction of creatine kinase) in children of the first year of life with congenital heart disease in the perioperative period. After cardiac surgery, plasma levels of the above markers exceed the reference limits in the examined children. The diagnosis of myocardial ischemia using biochemical markers in the postoperative period is possible only by dynamic monitoring of the cardiac marker level. The preoperative concentration of high-sensitivity troponin T in children of the first year of life with congenital heart disease can be regarded as a predictor of postoperative complications.

Experimental study of the effects of sodium ion concentrations on the function of the myocardium exposed to cardioplegic ischemia.

A new cardioplegic solution based on three natural dipeptides was developed and introduced at the Laboratory of Cardioplegia, A. N. Bakulev Research Center of Cardiovascular Surgery. The electrolyte composition of the solution corresponded to the category of intracellular cardioplegic solutions. The results of 60 experiments on isolated rat hearts were analyzed for choosing the optimal concentration of sodium ions (35, 60, or 80 mmol/liter). The composition of the studied cardioplegic solutions was selected by ion concentrations in the intra- and extracellular fluid. Earlier and most effective recovery of cardiac function with minimum rhythm and conductivity disorders was observed in the group treated with cardioplegic solution with sodium ion concentration of 60 mmol/liter.

Cardioprotective effect of histidine-containing dipeptides in pharmacological cold cardioplegia.

The cardioprotective effect of cardioplegic solution based on histidine-containing dipeptides was evaluated on isolated rat heart under conditions of hyporthermia and long ischemia. The use of natural dipeptides in cardioplegic solutions promoted an increase in the buffer capacity of myocardial cells and creation of an additional anti-ischemic effect under conditions of long ischemia and hypothermia.

Bioelectric impedancemetry of the myocardium during cardiac surgery with artificial circulation.

We analyzed changes in bioelectric impedance of the myocardium during cardiac surgery under conditions of cardioplegy. The results suggest the possibility of using bioelectric impedancemetry for evaluation of the state of the myocardium during surgery. Bioelectric impedancemetry allows evaluation of interstitium filling during infusion of the cardioplegic solution and reperfusion damage to cardiomyocytes.

Autoantibodies to myosin light chains in the blood as early marker of myocardial injury after aortocoronary bypass surgery.

Serum concentration of autoantibodies to myosin light chains was measured after resumption of the bloodflow recovery in patients who underwent hypothermic aortocoronary bypass surgery. The patients were divided into 3 groups according to postoperative hemodynamic parameters and degree of myocardial injury. The studies showed significant differences in the concentrations of autoantibodies to myosin light chains between the groups. High correlation was shown between the duration of aorta clamping and concentration of autoantibodies to myosin light chains. Some factors characterizing initial severity of the disease can modulate blood concentration of autoantibodies to myosin light chains.

Feasibility of myocardial pH-monitoring during heart surgery under conditions of cardioplegic ischemia.

The first results of the use of pH-monitoring of the myocardium with a Khuri monitor (Terumo Cardiovascular Systems Corporation) are presented. Before aorta clamping, the pH changes depended on the initial degree of damage to the examined myocardial segment. The cardioplegia protocol was urgently modified due to pH-monitoring, which helped to normalize pH and to prevent severe postoperative complications. The thermometric and pH-metric data were compared with the results of clinical and morphological studies. pH-monitoring made it possible to control myocardial vitality during the surgical intervention.