Особенности работы с минимизированной системой для кардиоплегии у детей. Стендовое испытание

It is very important to observe all the parameters of cardioplegia when protecting myocardium during cardiac surgery. To perform this task, it is necessary to have clear understanding of properties of the elements of the extracorporeal circuit of cardiopulmonary bypass.The objective: to develop a test model and using it to evaluate technical capabilities of blood cardioplegic system reducing the filling volume of the heat exchange chamber and the system supplying solution to the myocardium.Subjects and methods. A model of a neonatal cardiopulmonary bypass circuit was tested, it included an oxygenator and the cardioplegic system with a 7-ml heat exchange chamber; changes in the pressure and temperature in key nodes of the extracorporeal and cardioplegic circuits were assessed when the pump velocity, ambient temperature and fluid temperature in the main circuit were changed.Results. This modification provides a wide range of liquid volumetric velocities. Maintaining the selected variant of blood cardioplegia and safe pressure within the cardioplegic circuit is ensured at the perfusion rate of up to 350 ml/min. With normothermal circulation and air temperature in the operating room of 23°C, parameters of the cardioplegic circuit and solution delivery system allows maintaining the solution temperature within the range from 16 to 19°C. When the solution is cooled in a heat exchanger down to 4°C, the temperature of the final cardioplegic solution is maintained within 12-17°C; and with normothermal perfusion, air temperature in the operating room of 15°C and the solution temperature in the heat exchange chamber of 4°C, the temperature of the final cardioplegic solution can be within 6‒13°C. With perfusion in the mode of moderate hypothermia (32°C), air temperature in the operating room 15°C and temperature in the heat exchange chamber 4°C, the final cardioplegic solution can be delivered at the temperature from 5 to 9°C.Conclusions. The proposed test model allows investigating aimed to find out additional characteristics of the cardioplegic circuit.Ambient air temperature, cardioplegic pump velocity and main circuit fluid temperature are the main factors influencing the final cardioplegic solution temperature.When using the studied variant of the cardioplegic circuit assembly, the maintenance of the selected variant of blood cardioplegia and safe pressure inside the cardioplegic circuit are ensured at a perfusion rate of up to 350 ml/min.При обеспечении защиты миокарда во время операций на сердце принципиально важно четко соблюдать параметры проведения кардиоплегии. Эта задача реализуется посредством точного представления о свойствах компонентов экстракорпорального контура искусственного кровообращения.Цель: разработать тестовую модель и с ее помощью оценить технические возможности кровяной кардиоплегической системы с уменьшенным объемом заполнения камеры теплообмена и системы доставки раствора к миокарду.Материал и методы. Исследована тестовая модель неонатального контура искусственного кровообращения с использованием оксигенатора и кардиоплегической системы с объемом заполнения камеры теплообмена 7 мл с оценкой динамики давления и температуры в ключевых узлах экстракорпорального и кардиоплегического контура при изменении скорости работы насоса, температуры окружающей среды и жидкости в основном контуре.Результаты. Данная модификация полностью обеспечивает широкий диапазон объемных скоростей жидкости. Поддержание избранного варианта кровяной кардиоплегии и безопасного давления внутри кардиоплегического контура обеспечивается при скорости перфузии до 350 мл/мин. Возможности кардиоплегического контура и системы доставки раствора при нормотермической циркуляции и температуре воздуха в операционной 23°С позволяют обеспечивать поддержание температуры раствора в пределах от 16 до 19°С. При охлаждении раствора в теплообменном устройстве до 4°С температура конечного кардиоплегического раствора обеспечивается в пределах 12‒17°С, а при нормотермической перфузии, температуре воздуха в операционной 15°С и температуре раствора в камере теплообмена 4°С ‒ в пределах 6‒13°С. При перфузии в режиме умеренной гипотермии (32°С), температуре воздуха в операционной 15°С и температуре в камере теплообмена 4°С подача готового кардиоплегического раствора возможна с t от 5 до 9°С.Выводы. Предложенная тестовая модель позволяет проводить исследования с целью получения дополнительных характеристик кардиоплегического контура.Температура окружающего воздуха, скорость работы кардиоплегического насоса и температура жидкости в основном контуре являются основными факторами, влияющими на температуру конечного кардиоплегического раствора.При использовании исследованного варианта сборки кардиоплегического контура поддержание избранного варианта кровяной кардиоплегии и безопасного давления внутри кардиоплегического контура обеспечивается при скорости перфузии до 350 мл/мин

Specific parameters of operation of the minimized system for cardioplegia in children. Bench test

It is very important to observe all the parameters of cardioplegia when protecting myocardium during cardiac surgery. To perform this task, it is necessary to have clear understanding of properties of the elements of the extracorporeal circuit of cardiopulmonary bypass.The objective: to develop a test model and using it to evaluate technical capabilities of blood cardioplegic system reducing the filling volume of the heat exchange chamber and the system supplying solution to the myocardium.Subjects and methods. A model of a neonatal cardiopulmonary bypass circuit was tested, it included an oxygenator and the cardioplegic system with a 7-ml heat exchange chamber; changes in the pressure and temperature in key nodes of the extracorporeal and cardioplegic circuits were assessed when the pump velocity, ambient temperature and fluid temperature in the main circuit were changed.Results. This modification provides a wide range of liquid volumetric velocities. Maintaining the selected variant of blood cardioplegia and safe pressure within the cardioplegic circuit is ensured at the perfusion rate of up to 350 ml/min. With normothermal circulation and air temperature in the operating room of 23°C, parameters of the cardioplegic circuit and solution delivery system allows maintaining the solution temperature within the range from 16 to 19°C. When the solution is cooled in a heat exchanger down to 4°C, the temperature of the final cardioplegic solution is maintained within 12-17°C; and with normothermal perfusion, air temperature in the operating room of 15°C and the solution temperature in the heat exchange chamber of 4°C, the temperature of the final cardioplegic solution can be within 6‒13°C. With perfusion in the mode of moderate hypothermia (32°C), air temperature in the operating room 15°C and temperature in the heat exchange chamber 4°C, the final cardioplegic solution can be delivered at the temperature from 5 to 9°C.Conclusions. The proposed test model allows investigating aimed to find out additional characteristics of the cardioplegic circuit.Ambient air temperature, cardioplegic pump velocity and main circuit fluid temperature are the main factors influencing the final cardioplegic solution temperature.When using the studied variant of the cardioplegic circuit assembly, the maintenance of the selected variant of blood cardioplegia and safe pressure inside the cardioplegic circuit are ensured at a perfusion rate of up to 350 ml/min

Peculiarities of hemodynamic status of healthy newborns in early neonatal period

The study is devoted to the assessment of hemodynamic parameters in healthy newborns in the early neonatal period. The authors examined 76 healthy newborns aged up to 7 days. 12 (15.7%) of 76 children were diagnosed with intrauterine growth retardation of hypotrophic type and 14 children (18.49%) were premature. The authors evaluated the diameter of the outgoing tract of the left ventricle, pulmonary artery trunk, mitral and tricuspid valve rings. The disc method was used to determine the final diastolic volume of the left ventricle. The pulse Doppler was used to determine the integrated flow rate in the outflow tract of the left ventricle, the pulmonary artery trunk, on the mitral and tricuspid valves. After US there were calculated the stroke volume index, cardiac index, total peripheral vascular resistance and oxygen delivery index.The results. It integral flow rate was found to be a key indicator of central hemodynamics, which determines the magnitude of the stroke volume. Body weight and the presence of functioning fetal communications do not have a significant impact on the indexed systemic blood flow in healthy newborns. There is a direct correlation between the integral blood flow velocity and the stroke volume index, which is characteristic of all intracardiac anatomical structures

Evolocumab and clinical outcomes in patients with cardiovascular disease

peer reviewedBACKGROUND Evolocumab is a monoclonal antibody that inhibits proprotein convertase subtilisin-kexin type 9 (PCSK9) and lowers low-density lipoprotein (LDL) cholesterol levels by approximately 60%. Whether it prevents cardiovascular events is uncertain. METHODS We conducted a randomized, double-blind, placebo-controlled trial involving 27,564 patients with atherosclerotic cardiovascular disease and LDL cholesterol levels of 70 mg per deciliter (1.8 mmol per liter) or higher who were receiving statin therapy. Patients were randomly assigned to receive evolocumab (either 140 mg every 2 weeks or 420 mg monthly) or matching placebo as subcutaneous injections. The primary efficacy end point was the composite of cardiovascular death, myocardial infarction, stroke, hospitalization for unstable angina, or coronary revascularization. The key secondary efficacy end point was the composite of cardiovascular death, myocardial infarction, or stroke. The median duration of follow-up was 2.2 years. RESULTS At 48 weeks, the least-squares mean percentage reduction in LDL cholesterol levels with evolocumab, as compared with placebo, was 59%, from a median baseline value of 92 mg per deciliter (2.4 mmol per liter) to 30 mg per deciliter (0.78 mmol per liter) (P<0.001). Relative to placebo, evolocumab treatment significantly reduced the risk of the primary end point (1344 patients [9.8%] vs. 1563 patients [11.3%]; hazard ratio, 0.85; 95% confidence interval [CI], 0.79 to 0.92; P<0.001) and the key secondary end point (816 [5.9%] vs. 1013 [7.4%]; hazard ratio, 0.80; 95% CI, 0.73 to 0.88; P<0.001). The results were consistent across key subgroups, including the subgroup of patients in the lowest quartile for baseline LDL cholesterol levels (median, 74 mg per deciliter [1.9 mmol per liter]). There was no significant difference between the study groups with regard to adverse events (including new-onset diabetes and neurocognitive events), with the exception of injection-site reactions, which were more common with evolocumab (2.1% vs. 1.6%). CONCLUSIONS In our trial, inhibition of PCSK9 with evolocumab on a background of statin therapy lowered LDL cholesterol levels to a median of 30 mg per deciliter (0.78 mmol per liter) and reduced the risk of cardiovascular events. These findings show that patients with atherosclerotic cardiovascular disease benefit from lowering of LDL cholesterol levels below current targets. © 2017 Massachusetts Medical Society

Edoxaban versus warfarin in patients with atrial fibrillation

Contains fulltext : 125374.pdf (publisher's version ) (Open Access)BACKGROUND: Edoxaban is a direct oral factor Xa inhibitor with proven antithrombotic effects. The long-term efficacy and safety of edoxaban as compared with warfarin in patients with atrial fibrillation is not known. METHODS: We conducted a randomized, double-blind, double-dummy trial comparing two once-daily regimens of edoxaban with warfarin in 21,105 patients with moderate-to-high-risk atrial fibrillation (median follow-up, 2.8 years). The primary efficacy end point was stroke or systemic embolism. Each edoxaban regimen was tested for noninferiority to warfarin during the treatment period. The principal safety end point was major bleeding. RESULTS: The annualized rate of the primary end point during treatment was 1.50% with warfarin (median time in the therapeutic range, 68.4%), as compared with 1.18% with high-dose edoxaban (hazard ratio, 0.79; 97.5% confidence interval [CI], 0.63 to 0.99; P<0.001 for noninferiority) and 1.61% with low-dose edoxaban (hazard ratio, 1.07; 97.5% CI, 0.87 to 1.31; P=0.005 for noninferiority). In the intention-to-treat analysis, there was a trend favoring high-dose edoxaban versus warfarin (hazard ratio, 0.87; 97.5% CI, 0.73 to 1.04; P=0.08) and an unfavorable trend with low-dose edoxaban versus warfarin (hazard ratio, 1.13; 97.5% CI, 0.96 to 1.34; P=0.10). The annualized rate of major bleeding was 3.43% with warfarin versus 2.75% with high-dose edoxaban (hazard ratio, 0.80; 95% CI, 0.71 to 0.91; P<0.001) and 1.61% with low-dose edoxaban (hazard ratio, 0.47; 95% CI, 0.41 to 0.55; P<0.001). The corresponding annualized rates of death from cardiovascular causes were 3.17% versus 2.74% (hazard ratio, 0.86; 95% CI, 0.77 to 0.97; P=0.01), and 2.71% (hazard ratio, 0.85; 95% CI, 0.76 to 0.96; P=0.008), and the corresponding rates of the key secondary end point (a composite of stroke, systemic embolism, or death from cardiovascular causes) were 4.43% versus 3.85% (hazard ratio, 0.87; 95% CI, 0.78 to 0.96; P=0.005), and 4.23% (hazard ratio, 0.95; 95% CI, 0.86 to 1.05; P=0.32). CONCLUSIONS: Both once-daily regimens of edoxaban were noninferior to warfarin with respect to the prevention of stroke or systemic embolism and were associated with significantly lower rates of bleeding and death from cardiovascular causes. (Funded by Daiichi Sankyo Pharma Development; ENGAGE AF-TIMI 48 ClinicalTrials.gov number, NCT00781391.)