• Journal of Chest Surgery
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• v.18 no.4
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• pp.759-770
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• 1985

This study was experimentally undertaken to evaluate the effect of hypothermic oxygenated cardioplegic solution on myocardial protection during prolonged aortic cross clamping under cardiopulmonary bypass. Dogs were divided into two groups control group [received hypothermic unoxygenated cardioplegic solution] and experimental group [received hypothermic oxygenated cardioplegic solution]. Coronary sinus effluent was obtained at once and 30, 60, 90 minutes after cross-clamping for the determination of pH, PCO2,PO2 and lactate level during the infusion of cardioplegic solution and myocardial biopsies were obtained after cessation of 90 minutes of aortic cross-clamping. The results obtained were as follows: 1. There was no significant differences in the pH and PCO2 between the oxygenated and unoxygenated cardioplegic solution but the PO2 of the oxygenated solution was 4 times greater than unoxygenated solution, and also the oxygenated solution had a significantly greater oxygen content [2.020.05 ml 02/min] and had much more oxygen delivery than unoxygenated solution. 2. The myocardial oxygen consumption and the myocardial oxygen extraction in oxygenated group were 1.63 ml 02/100 ml and 67.32% respectively, which was greater than those in unoxygenated group. 3. Regarding to pH and PCO2 of coronary sinus effluent, there was no significant differences between two groups in early period of infusion of cardioplegic solution, but the pH shifted to acidosis from 60 minutes, PCO2 increased from 90 minutes of aortic cross-clamping, and PO2 markedly decreased from 90 minutes of aortic cross-clamping in unoxygenated group. 4. The lactate concentration of coronary sinus effluent revealed relatively normal in both groups, but showed slight increase up to 27.54.56 mg/100 ml at 90 minutes of aortic cross-clamping in unoxygenated group. 5. On electron microscopic study, the ultrastructural integrity of myocardial cells in oxygenated group was well preserved within 90 minutes. Slight swelling and deformity of mitochondria, interfibrillar widening, and disarrangement of myofibrils were observed at 90 minutes after aortic cross-clamping in unoxygenated group. From these results, the use of hypothermic oxygenated cardioplegic solution seemed to be effective and better method for the preservation of ischemic myocardium during the prolonged aortic cross-clamping.

• Journal of Nutrition and Health
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• v.25 no.7
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• pp.597-607
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• 1992

The present study examined effects of caffeine on coronary circulation myocardial oxygen me-tabolism and calcium release in isolated perfused guinea pig hearts. Intracoronary caffeine({{{{ {10 }^{-5 } }}}}∼{{{{ { 10}^{-3 } }}}}M) was employed for 10 minutes to measure coronary perfusate flow(CF) and coronary vascular sresistance(CVR) at a constant coronary perfusion pressure of 80 cmH2O Perfusate myocardial oxygen consumption(MVO2) and percent oxygen extraction(%EC2) were calcula-ted. In addition calcium contents in both perfusate samples were measured to calculate calcium release in coronary venous effluent. Caffeine significantly decreased CF and increased CVR during 10 minutes of caffeine perfusion regardless of dose of caffeine perfused exhibiting time-response. While % EO2 was significantly enhanced with caffeine MVO2 was markedly reduced. The coronary venous perfusate pH dcreased during the perfusion with caffeine. These changes were consistent with caffeine-induced metabolic acidosis. Calcium release appeared to be dose-dependent and high dose of caffeine greatly increased venous calcium release even 2 minutes after perfusion with carffeine. These finding in dicate that caffeine produced coronary vasoconst-riction with increased calcium release in isolated perfused guinea pig hearts. Additionaly this vasoconstrictor response mignt be due tin part to the direct actions of caffeine.

• Journal of Korean Physical Therapy Science
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• v.4 no.1
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• pp.243-253
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• 1997

The purpose of this study was to determine the effect of systolic blood pressure, heart rate and myocardial oxygen consumption on 3-point nonweight bearing ambulation with axillary wooden crutch according to age. The subjects were fifty healty volunteers(22 male, 28 female), ages from 20 to 69(mean age of 43.8 years) with no history of cardiovascular or respiratory disease, diabetes mellitus, arthritis and orthopedic disorder within the past three years. This study was carried out from May 10 to August 10, 1996. The data were analyzed by percentage, mean and standard deviation and ANOVA. The results were as follows : 1. In systolic blood pressure(SBP), there was no significantly change between before walk and after 20 m in crutch walking with age, however, there did differ significantly after 40 m and 60 m in crutch walking(p<0.01, p<0.001). 2. In heat rate(HR), there was no significantly change between before walk and after 20 m, 40 m in crutch walking with age, however, there did differ significantly after 60 m in crutch walking(p<0.05). 3. In myocardial oxygen consumption($MVO_{2}$), there was no significantly change between before walk and after 20m in crutch walking with age, however, there did differ significantly after 40 m and 60 m in crutch walking(p<0.01, p<0.001). These result showed that cardiovascular system had a great effect on the olderly when 3-point nonweight bearing ambulation with axillary wooden crutch. Therefore, when train for axillary crutch in the olderly, we needed suitably basis of walking distance.

• Journal of Biomedical Engineering Research
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• v.17 no.1
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• pp.43-48
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• 1996

We investigated the energistics of the physiological heart model by comparing predictive indexes of the myocardial oxygen consumption (MOC), such as tension-time index (R), tension-time or force-time inteual (FTI), rate-pressure product (RPP), pressure-work index, and systolic pressure-volume area (PVA) when using the electro-hydraulic left ventricular device (LVAD). We developed the model of LVAD incorporated the closed-loop cardiovascular system with a baroreceptor which can control heart rate and time-varying elastance of left and right ventricles. On considering the benefit of the LVAD, the effects of various operation modes, especially timing of assistance, were evaluated using this coupled computer model. Overall results of the computer simulation shows that our LVAD can unload the ischemic (less contractile) heart by decreasing the MU and increasing coronary flow. Because the pump ejection at the end diastolic phase of the natural heart may increase the afterload of the left ventricle, the control scheme of our LVAD must prohibit ejecting at this time. Since the increment of coronary flow is proportional to the peak aortic pressure after ventricle contraction, the LVAD must eject immediately following the closure of the aortic valve to increase oxygen availability.

• Journal of Korean Academy of Nursing
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• v.33 no.6
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• pp.693-704
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• 2003

Purpose: The purpose of this study was to determine whether a relaxing music was effective in reducing stress response of patients admitted to a coronary care unit with the diagnosis of acute myocardial infarction. Method: The research design was the chosen convenience sample of a randomized control group pre-posttest quasi-experimental design. Forty patients, 20 for an experimental group and another 20 for control group. The study was to provide the patients three different kinds of relaxing music. The experimental group listened to relaxing music for a 20-minute one time a day for 3days. The control group was just provided with a 20-minute period of rest. Test for hypothesis was done by repeated measured ANOV A. Result: The experimental group which received relaxing music showed a significantly lower level of electrodermal response, myocardial oxygen consumption and respiration rate, and a higher level of peripheral skin temperature than the control group. The experimental group which received relaxing music showed a significant reduction in state anxiety than the control group. Conclusion: The results showed that relaxing music is an effective nursing intervention for reducing physiologic and psychologic stress response of the patients with acute myocardial infarction in a critical intensive care unit.

• Journal of Chest Surgery
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• v.20 no.4
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• pp.643-654
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• 1987

The effect of prostacyclin[PGI, ] on myocardial preservation during global ischemia was studied in the isolating working rabbit heart model. Forty hearts underwent a 15 minute period of retrograde nonworking perfusion with Krebs-Henseleit buffer solution [37*C] and were switched over to the working mode for 15 minutes. After baseline measurement of heart rate, peak aortic pressure, aortic flow, and coronary flow, all hearts were subjected to 60 minutes of ischemic arrest at 10*C induced with St. Thomas Hospital cardioplegic solution: Group I had single dose cardioplegia, Croup II double dose, Croup III oxygenated double dose, and Group IV single dose with PCI, infusion [10ng/min./gm heart weight]. Hearts were then revived with 15 minute period of nonworking reperfusion at normothermia, followed by 30 minutes of working perfusion. Repeat measurements of cardiac function were obtained and expressed as a percent of the preischemic baseline values. Oxygen content of arterial perfusate and coronary effluent was measured by designed time interval. Leakage of creatine kinase was determined during post-ischemic reperfusion period. Finally wet hearts were weighed and placed in 120*C oven for 36 hours for measurement of dry weight. In the PGI, treated group [IV], heart rate increased consistently throughout the period of reperfusion from 100*5.0% [p<0.001] to 107*6.2% [p<0.001]. The percent recovery of aortic flow showed 95*5.7% [p<0.001] at the first 3 minute and full recovery through the subsequent time. Coronary flow was augmented significantly in the 3 minute [96*6.2%, p<0.001] and then sustained above baseline values. Among the Croup I, II, and III, all hemodynamic values were significantly below preischemic levels. PGI2 relatively increased oxygen delivery [1.22*0.19ml/min, p<0.001] and myocardial oxygen consumption [0.90*0.13ml/min, p<0.001] during reperfusion period. Leakage of creatine kinase in the PGI2 group was 9.3*1.58IU/15min [p<0.001]. This was significantly lower than Group I [33.0*2.68 IU/15min]. The water content of PCI2 treated hearts [81*0.9%, p<0.001] was also lower than the other groups.

• Journal of Nutrition and Health
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• v.28 no.2
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• pp.115-126
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• 1995

The effects of energy-yielding substrates on coronary circulation, myocardial oxygen metabolism, and intramyocytic adenylates of perfused Wistar control rat(WC) and spontaneously hypertensive rat(SHR) hearts were examined under basal and $\beta$-adrenergic stimulation conditions. The perfusion medium (1.0mM Ca2+) contained 5mM glucose (+5U/l insulin) in combination with 5mM pyruvate, 5mM lacate, 5mM acetate, or 5mM octanoate as energy substrates. Hearts were perfused with each substrate buffer for 20min under basal conditions. Coronary functinal hyperemia was induced by infusing for 20min isoproterenol (ISO, 1uM), a $\beta$-receptor agonist. Cardiac adenylates, glycolytic intermediates, and coronary venous lactate were measured by using an enzymatic analysis technique. Under basal conditions, acetate and octanoate significantly increased coronary flow(CF) of WC in parallel with myocardial oxygen consumption. However, CF of SHR was partly attenuated by coronary vasoconstriction despite metabolic acidosis. In addition, pyruvate and lactate depressd ISO-induced coronary functional hyperemia in SHR. It should be noted that octanoate exhibited coronary dysfunction under ISO conditions. On the other hand, fat substrates depleted myocardial high energy phosphate pool and accumulated breakdown intermediates. In SHR with coronary vasoconstriction under basal conditions, and with depressed coronary functional hyperemia, high energy phosphates were greatly depleted. These results suggest that energy substrates in the myocardium and coronary smooth muscle alter remarkably coronary circulation, and that coronary circulatory function is associated with a reserve of high energy phosphates and a balance between breakdown and nono synthesis of energy phosphates. These findings could be explained by alterations in the cytosolic redox state manipulated by LDH and hence in the cytosolic phosphorylation potential, which might be involved in hypertension of SHR.

• Journal of Chest Surgery
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• v.27 no.7
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• pp.571-575
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• 1994

The hemodynamic effects of thyroid hormone are well established, and this hormone affects myocardial contractility, heart rate, and myocardial oxygen consumption. But the role of cardiopulmonary bypass on the thyroid function is not yet fully understood. We have studied twelve patients [male and female patients were equal in number] who were performed open heart surgery under cardiopulmonary bypass. The results are followed. 1] The serum level of T3 began to fall after cardiopulmonary bypass and sustained significantly till 24 hours after operation[p<0.05] 2] The concentrations of T4, Free T4, and TSH were slightly decreased after cardiopulmonary bypass but was maintained within normal range. 3] This above findings are similar to the "sick sinus syndrome" that is seen in severely ill patient. 4] We can propose that T3 would be effective in postoperative low cardiac output syndrome. syndrome.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.213-220
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• 1994

Gastrodia (G) Rhizoma has been used clinically as an oriental herbal medicine with sedative, anticonvulsive, and depressor effects. The present study tested effects of G. Rhizoma extracts on the coronary circulation and myocardial oxygen consumption in perfused rat hearts. Sprague Dawley rats (SD) and spontaneously hypertensive rats (SHR) were employed as experimental animals and nonworking Langendorff heart perfusion technique introduced for heart experiments. G. Rhizoma extracts were prepared from grinding G. Rhizoma into powder, extracting in water and 50% ethanol for 4 or 16 hr and diluting with Krebs-Henseleit bicarbonate perfusion buffer to be 70%. Hearts were perfused with bicarbonate buffer oxygenated with 95% $O_{2}:$ 5% $CO_{2}$ at constant coronary perfusion pressure of $90cmH_{2}O$. The diluted extracts were infused into coronary arteries in a concentration of $1{\sim}5\;{\mu}M$ for $7{\sim}8 min. While in SD water- or ethanol-extracts of G. Rhizoma extracted for 16 hr increased coronary perfusate flow (CPF) and decreased coronary vascular resistance (CVR), ethanol-extracts in SHR produced coronary vasoconstriction associated with enhanced CVR. G. Rhizoma extracts-induced increase in CPF reduced myocardial oxygen extraction, and thus myocardial oxygen consumption ($MVO_{2}$) remained at that observed prior to infusion of extracts. In SD and SHR 16 hr-water-extracts markedly altered coronary venous effluent pH and $Pco_{2}$ and evoked metabolic acidosis, which could be a coronary vasodilator mechanism decreasing CVR. In this study, the extracts decreasing CVR in SD and SHR did not augment the lactate production. Therefore, although the effects of the extracts on cardiac function and coronary circulation depended on solvents and duration for extraction, the 16hr-water-extracts, at least, exhibited coronary vasodilation in SD and SHR. Conversely, ethanol-extracts constricted coronary arteries in SHR. G. Rhizoma extracts-induced vasodilation might be due to the metabolic acidosis rather than due to the increased lactate production. The results indicate that G. Rhizoma extracts obtained from proper extracting procedures can be used as a safe and clinically applicable herbal medicine in the cardiovascular diseases such as coronary artery disease and hypertension for vasodilatory and antihypertensive actions.

• Journal of Ginseng Research
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• v.43 no.4
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• pp.517-526
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• 2019

Background: The root of Panax ginseng, a member of Araliaceae family, has been used as herbal medicine and functional food in Asia for thousands of years. According to Traditional Chinese medicine, ginseng is the most widely used "Qi-invigorating" herbs, which provides tonic and preventive effects by resisting oxidative stress, influencing energy metabolism, and improving mitochondrial function. Very few reports have systematically measured cell mitochondrial bioenergetics after ginseng treatment. Methods: Here, H9C2 cell line, a rat cardiomyoblast, was treated with ginseng extracts having extracted using solvents of different polarity, i.e., water, 50% ethanol, and 90% ethanol, and subsequently, the oxygen consumption rate in healthy and tert-butyl hydroperoxideetreated live cultures was determined by Seahorse extracellular flux analyzer. Results: The 90% ethanol extracts of ginseng possessed the strongest antioxidative and tonic activities to mitochondrial respiration and therefore provided the best protective effects to H9C2 cardiomyocytes. By increasing the spare respiratory capacity of stressed H9C2 cells up to three-folds of that of healthy cells, the 90% ethanol extracts of ginseng greatly improved the tolerance of myocardial cells to oxidative damage. Conclusion: These results demonstrated that the low polarity extracts of ginseng could be the best extract, as compared with others, in regulating the oxygen consumption rate of cultured cardiomyocytes during mitochondrial respiration.