[Intraventricular blood flows and myocardial contractility in impairments of coronary circulation]. / Vnutrizheludochkovye potoki krovi i sokrashchenie miokarda pri narusheniiakh koronarnogo krovoobrashcheniia.

We examined a total of 106 patients with ischaemic heart disease (mean age - 59±7 years) and 30 apparently healthy people (mean age - 36±4 years). Myocardial revascularization was performed with the help of stenting and coronary artery bypass grafting. The patients with ischaemic heart disease were divided into 2 groups: Group 1 with postinfarction cardiosclerosis and Group 2 without Q-forming myocardial infarction. Echocardiography was performed using the Vivid E9 machine prior to operation, intraoperatively, and 10-14 after the intervention. We registered the end-systolic volume and end-diastolic volume of the left ventricle, ejection fraction, cardiac index. Alterations of velocity were assessed in relation to of the volume of the left ventricle (dVol/dt), length of the ventricle (dL/dt) in systole and diastole, as well as myocardial shift velocity in 3 endocardial regions - basal (V1), middle (V2), apical portions (V3) and interrelationship with intraventricular blood flows. It was determined that myocardial dysfunction leads to impairment of the structure of the flow, change of acceleration, which is accompanied by a decrease in the cardiac productivity. Impairment of segmental contractility of the left ventricle is manifested by a decrease of vectors of myocardial motion velocity by more than 20%. Intraventricular flows in cardiac chambers may serve as predictors of adequacy of correction of coronary pathology.

[Vector mapping of deformation and blood flows in patients with ascending aortic aneurysm]. / Vektornoe kartirovanie deformatsii i potokov krovi u patsientov s anevrizmoi voskhodiashchei aorty.

The authors performed clinical studies based on modelling of an ascending aortic aneurysm in 37 patients and 10 apparently healthy subjects. Echocardiography was carried out in the B-mode using the Vivid E9 device (USA, GE). The linear dimensions of the aorta were assessed at three points - in the immediate vicinity of the valves, in the area of the maximum dilatation and in the area of decreased dilatation with registration of blood flow velocity in the aorta. The aortic walls were contoured with the division of equal intervals into 4 portions in order to obtain longitudinal shear deformation velocity during the cardiac cycle. We worked out a system of assessing the velocity vector fields with the help of transthoracic echocardiography in patients with an ascending aortic aneurysm, based on registration of blood flows, which made it possible to obtain the components of velocity. We also determined an optimal method of assessing turbulence in the aorta taking into account the direction of the vectors. Obtained were the numerical data of aortic wall deformation velocity in the longitudinal direction and calculation of the weighting function with the distinction between pathology and the norm. Based on the deformation, the distance between the registered points, and the movement of the vascular wall, we determined the reference values of blood flow velocity inside the aorta and immediately close to its walls.

[Noninvasive registration of turbulent flows in the left ventricle].

Observation results of 133 patients with chronic heart insufficiency and 29 healthy people, all aged 41 ± 6 years were analyzed. 51 patients had ischemic heart disease, 53 had various valvular diseases and 30 patients had dilated cardiomyopathy. Echocardiography was performed together with ECG. Blood flows in left ventricle, myocardium shift velocity and pressure gradients during the heart cycle were measured. The study showed that systole leads to the directional change of blood flows within the heart cycle, accompanied by turbulence phenomenon with extremely high flow velocities. Detection of vortex flows and velocity vector characterizes changes of flow direction. All patients of the main group were operated on with the use of modern methods of heart remodeling. The principally novel method of surgical treatment, allowing to preserve the patient's heart, was worked out.

[Cardiorespiratory exercise tolerance tests: a preoperative surgical risks assessment in elderly patients].

This study focuses on the most topical issue: non-cardiac surgery safety in elderly patients. According to different authors data, the mortality rate due to cardiovascular pathology %, and postoperative cardiac events incidence -from 2 to 4.4 %. For this reason we decided to conduct prospective risk assessment in the most dificult elderly patients group. Within the framework of this study we performed cardiorespiratory exercise testing (KAREN-test) in 17 elderly patients with various located colon cancer Concomitant diseases were: ischemic heart disease (12 patients), postinfarction cardiosclerosis (4 patients), arterial hypertension (12 patients), rhythm disturbances of varying degrees (11 patients), CHF (2 patients), and others. Patients were aged from 58 to 94 years. Subsequently, 14 of 17 patients were operated on, 11 of them underwent radical intervention. Cardiorespiratory exercise tolerance test was carried out according to moderate treadmill-test protocol for elderly patients developed in our clinic. Test duration was more than 4 minutes in all patients. During exercise stress peak, submaximal heart rate was observed in all patients, the peak oxygen consumption to a maximum current oxygen consumption ratio amounted to 94% on the average in a group, the oxygen consumption at the aerobic threshold level exceeded 11 mI/min/kg in all patients. There was no acute myocardial infarction and cerebrovascular events during perioperative period; the hospital mortality rate was 0%. Actual age by itself is not a contraindication for surgery. KAREN tests should become one of the key components for the assessment and treatment tactics choice.

[Effect of propofol-based combined anesthesia on the development of adaptive mechanisms to the prolonged one-lung artificial ventilation].

The paper deals with the assessment of the adequacy and safety of multicomponent anesthesia based on propofol at lung surgery requiring one-lung ventilation (OLV) in patients with chronic respiratory diseases and with the evaluation of the effect of propofol on the development of adaptive mechanisms in various ventilation modalities in thoracic surgery. The pressor, resistive, and volume characteristics of pulmonary blood flow, systemic and intracardiac hemodynamics under artificial ventilation (AV) and OLV of a duration of up to 1.5 hours by a combination of pulmonal and transpulmonal thermodilution on a PiCCO plus device with a VOLEF attachment were compared. Multicomponent balanced anesthesia based on continuous graduated propofol infusion provides adequate protection of patients during thoracic operations, including those with concomitant respiratory abnormality.

[Myocardial biomechanics in patients with coronary circulatory insufficiency].

The paper analyzes a new approach to evaluating myocardial systolic and diastolic function, which is based on recording of the rate of myocardial displacement in different phases of a cardiac cycle. Changes in the rate of vector movements in a period of isovolumic contraction and relaxation are shown on ample clinical materials in both healthy individuals and patients with coronary heart disease. There is evidence for a significant difference in the performance of a stress test by healthy individuals and patients with a low coronary circulatory reserve.

[Use of loading test to predict intraoperative heart failure in cardiosurgical patients].

The paper deals with the development of a procedure for using loading tests to predict the development of intraoperative heart failure in cardiosurgical patients. A volumetric loading test (limb elevation) was carried out to assess the mechanisms of responsible for the regulation of performance of the heart and the efficiency of its work. Cardiac output, end diastolic volume index, and ejection fraction were recorded and a hemodynamic response was assessed from their changes. Loading tests enabled the authors to identify 3 types of a hemodynamic response to a volumetric load. The incidence of postperfusion heart failure may be predicted depending on the identified type of a hemodynamic response to the volumetric load given at the very beginning of surgery.

[Sevoflurane and isoflurane during thoracic operations under artificial one-lung ventilation in patients at a high surgical and anesthesiological risk].

The specific features of balanced anesthesia utilizing sevoflurane (versus isoflurane) during thoracic operations under artificial one-lung ventilation (AOL ) have been studied in patients at high operative and anesthetic risks. Unlike isoflurane, sevflurane fails to cause vasodilatation in both the greater and lesser circulation (including in the gas-exchange part ofpulmonary circulation). The difference of the anesthetics in their vasodilating capacity in the vessels of pulmonary and systemic circulation determines various mechanisms of pathophysiological and adaptive circulatory changes in pulmonary collapse and under AOL V Under sevoflurane anesthesia, compensatory blood flow limitation along the collaborated lung due to permanently vasohypertension in gas-exchange microcirculation is accompanied by a systemic circulatory response that is aimed at reducing right ventricular load. Termination of hypoxic pulmonary vasoconstriction in the collaborated lung occurs not early than 80-125 min of AOLV, fails to lead to recovery of impaired gas exchange due to vasohypertension and high shunt in the ventilated lung, and is attended by right ventricular overload. The latter differentiates sevoflurane anesthesia from isoflurane one wherein completion of pulmonary hypoxic vasoconstriction upon 80-125-min exposure to AOL V results in the recovery of gas exchange to the baseline levels. The pattern of reperfusion changes in ventilation emergence in the operated lung under anesthesia using both sevoflurane and isoflurane is of no significant pathological tinge and it is followed by no pulmonary and systemic metabolic disturbances. Isoflurane should be recognized to be preferable component at the stage of anesthesia maintenance in patients with cardiopulmonary diseases during thoracic operations under prolonged AOL V (more than 2 hours).

[Impact of combined anesthesia using isoflurane on the development of adaptation mechanisms on changing ventilation conditions in thoracic surgery].

The paper deals with the effect of isoflurane (IF) as a component of combined anesthesia during thoracic interventions in the lateral position on the development of adaptation mechanisms to a change in artificial ventilation (AV) modes--from ventilation of both lungs to that of one lung (unilateral ventilation, ULV), long exposure to ULV and to a change from ULV to ventilation of both lungs. Eighteen patients at a high operation-anesthetic risk were examined. Measurements were made in 6 steps, including conditions in AV, exposure to ULV for 15-30, 55-60, and 80-120 minutes, AV after 20-min exposure to ULV, and at the end of surgery in the supine position. While analyzing the results, the authors made an important observation that IF has a property of preventing capillary formation in the ventilated portions, without impairing the mechanism of pulmonary hypoxic vasoconstriction in the area of atelectized alveoles. This contributed to the optimization of a ventilation-perfusion relationship and creates conditions for adequate oxygenation. The use of IF as a component of combined anesthesia during thoracic operations associated with a need for artificial unilateral ventilation in patients at a high operation-anesthetic risk created conditions for optimizing gas exchange and blood circulation at all stages of an operation and anesthesia.