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PubMed1995

Hemodynamic changes in HH stage 34 chick embryos after treatment with all-trans-retinoic acid.

To obtain insight into the hemodynamics of abnormal cardiac development, a chick embryo model was recently developed in which a spectrum of double outlet right ventricle was induced with all-trans-retinoic acid. In Hamburger and Hamilton (HH) stage 34 white Leghorn chick embryos, we simultaneously measured dorsal aortic flow velocities with a 20 MHz pulsed Doppler velocity meter and vitelline artery blood pressures with a servonull system. These measurements were performed in embryos treated at HH stage 15 with 1 microgram of all-trans-retinoic acid (n = 47), or with the solvent DMSO (n = 15), and in control embryos (n = 21). After the wave form recordings were collected, all embryos were examined histologically. Embryos treated with all-trans-retinoic acid showed in 15 cases hearts with a rightward positioned aorta with an additional subaortic ventricular septal defect and 32 cases without septation abnormalities of the heart. The hemodynamic data were correlated with the morphology. Statistical comparison was performed between control and experimental values. There was no significant discrepancy in hemodynamics of sham-operated and control embryos. Heart rate, peak systolic and mean velocities, peak systolic and mean blood flows, and peak acceleration and stroke volume were reduced in embryos treated with all-trans-retinoic acid (p < 0.01). Furthermore, in the presence of a subaortic ventricular septal defect the diameter of the dorsal aorta was reduced. Pressure readings were not statistically significant. Our findings suggest that the hemodynamic changes are the result of a decrease in cardiac contraction force.

Animals↗
PubMed2001

Mood states and impedance cardiography-derived hemodynamics.

OBJECTIVE: This exploratory study investigated the relation between psychological mood states and hemodynamic variables obtained at rest. METHODS: We measured resting hemodynamic variables using impedance cardiography, blood pressure, heart rate, and the Profile of Mood States (POMS) in 71 participants. RESULTS: Mood states were not significantly associated with heart rate, systolic, diastolic, or mean arterial pressure. In comparison with these basic measures of physiology, a number of impedance derived measures of hemodynamics were associated with mood states. Log stroke volume was negatively correlated with POMS tension-anxiety (r = -.319, p = .009) and fatigue-inertia (r = -. 316, p = .009). Log cardiac output was negatively associated with fatigue-inertia (r = -.346, p < .01). Log total peripheral vascular resistance was positively correlated with POMS fatigue-inertia (r = .276, p = .024). CONCLUSIONS: Our findings suggest that mood states are associated with hemodynamic variables underlying blood pressure.

Adult↗
PubMed2001

GATA4 mediates activation of the B-type natriuretic peptide gene expression in response to hemodynamic stress.

To identify the mechanisms that couple hemodynamic stress to alterations in cardiac gene expression, DNA constructs containing the rat B-type natriuretic peptide (BNP) promoter were injected into the myocardium of rats, which underwent bilateral nephrectomy or were sham-operated. Ventricular BNP mRNA levels were induced about 4-fold; and the BNP reporter construct containing the proximal 2200 bp, 5-fold, in response to 1-d nephrectomy. Deletion of sequences between bp -2200 and -114 did not affect basal or inducible activity of the BNP promoter. An activator protein-1-like site and two tandem GATA elements are located within this 114-bp sequence. Both deletion and mutation of the AP-1-like motif decreased basal activity but did not abolish the response to nephrectomy. In contrast, mutation or deletion of -90 bp GATA-sites abrogated the response to hemodynamic stress. The importance of these GATA elements to BNP promoter activation was further confirmed by the corresponding 38-bp oligonucleotide conferring hemodynamic stress responsiveness to a minimal BNP promoter. In gel mobility shift assays, nephrectomy increased left ventricular BNP GATA4 binding activity significantly. In conclusion, GATA elements are necessary and sufficient to confer transcriptional activation of BNP gene in response to hemodynamic stress.

Amino Acid Motifs↗
PubMed2000

Recurrent ischemia in symptomatic carotid occlusion: prognostic value of hemodynamic factors.

OBJECTIVE: To identify hemodynamic factors that predict recurrence of ipsilateral cerebral ischemic events in patients with symptomatic carotid artery occlusion (CAO). PATIENTS AND METHODS: The authors studied 117 consecutive patients with CAO and corresponding recent (</=6 months) ischemic symptoms of the brain or eye that were transient or at most mildly disabling. They determined, using Cox proportional hazards analysis, the prognostic value for recurrence of ipsilateral cerebral ischemic events of 1) clinical features believed to indicate hemodynamic compromise, 2) collateral blood flow pattern, and 3) transcranial Doppler CO(2)-reactivity. RESULTS: None of the 24 patients with symptoms of retinal ischemia alone had a recurrent cerebral ischemic event. In the 93 patients with cerebral ischemic symptoms on entry, recurrence of these symptoms was independently predicted by 1) the nature of the initial symptoms being of purported hemodynamic origin (limb-shaking, precipitation of symptoms by rising, exercise or low blood pressure, retinal claudication) (hazard ratio [HR] 3.8, 95% CI 1.5 to 9.5), 2) continuing symptoms after the CAO had been documented, but before inclusion in the study (HR 5.9, 95% CI 2.2 to 16.1), and 3) the presence of collateral blood flow via leptomeningeal vessels (HR 4.1, 95% CI 1.3 to 13.1). CO(2)-reactivity did not predict recurrence of cerebral ischemic events. CONCLUSIONS: Having cerebral in contrast to retinal ischemia, clinical features suggestive of hemodynamic compromise, continuing symptoms after demonstration of the CAO, and presence of leptomeningeal collaterals may help to identify patients with symptomatic CAO at high risk of future cerebral ischemia.

Aged↗
PubMed1990

Hemodynamic effects of rapid vancomycin infusion in critically ill patients.

The rapid infusion of vancomycin produces histamine release resulting in rash ("red-man's" syndrome) and hypotension. Because this phenomenon has been described primarily in healthy subjects, we prospectively studied the rapid infusion of vancomycin in 16 critically ill patients after open heart surgery in an attempt to document histamine release with resulting hemodynamic changes, and to see if there is any correlation with vancomycin levels. After establishing baseline hemodynamic stability and histamine levels, 1 g vancomycin diluted in 50 mL of 5% dextrose was infused over 30 min. Cardiac index, heart rate, blood pressure, pulmonary venous pressures, and systemic and pulmonary vascular resistances remained unchanged during the infusion. Although the mean plasma vancomycin level increased to a peak of 69 +/- 20 micrograms/mL after 20 min of the infusion before declining, mean plasma histamine levels in 15 of the 16 patients remained within the normal range during the infusion. In one patient a baseline histamine level (2.8 ng/mL) more than three times the normal before the vancomycin infusion increased further during the infusion (3.0, 4.9, and 5.0 ng/mL at t = 10, 20, and 30 min, respectively), and remained elevated (2.9 ng/mL) 30 min after the infusion. This patient developed the red-man's syndrome, although there were no hemodynamic changes. There was no evidence of myocardial depression in any of the patients. In conclusion, we safely infused a concentrated solution of vancomycin into critically ill patients over 30 min without any adverse hemodynamic changes. One patient developed the red-man's syndrome. There was no correlation between peak vancomycin levels and the release of histamine in this patient population.

Adult↗
PubMed2003

Hemodynamic responses among three tracheal intubation devices in normotensive and hypertensive patients.

UNLABELLED: We compare hemodynamic responses in normotensive and hypertensive anesthetized paralyzed patients among three intubation devices: the Macintosh laryngoscope (LS), the Trachlight lightwand (LW), and the intubating laryngeal mask airway Fastrach (ILM). Seventy-five normotensive and 75 hypertensive patients were randomly assigned to each intubation device (n = 25). Noninvasive systolic blood pressure (SBP) and diastolic blood pressure (DBP) and heart rate (HR) were recorded immediately preinduction, immediately preintubation, and every minute for the first 5 min after the successful intubation. The number of intubation attempts, the time to successful intubation, and any airway injuries were recorded. Pharyngolaryngeal morbidity was assessed 18-24 h after surgery by a blinded investigator. In all groups, there was a reduction in SBP and DBP but no change in HR immediately preintubation compared with baseline values. In all groups, HR increased, but there were no increases in SBP and DBP other than in DBP in the LS/hypertensive group after intubation compared with baseline values. In normotensive patients, there were no differences in any hemodynamic variables among the three devices. In hypertensive patients, SBP and DBP in the LS group were significantly higher than the ILM and LW groups for 2 min after intubation, but there were no differences in HR among the devices. The number of intubation attempts was similar among groups, but intubation time was longer for the ILM group. The incidence of airway injury was more frequent for the ILM than the LS and LW groups (16% versus 0% versus 0%). There were no differences in pharyngolaryngeal morbidity among groups. We conclude that both the ILM and the LW attenuated the hemodynamic stress response to tracheal intubation compared with the LS in hypertensive, but not in normotensive, anesthetized paralyzed patients. IMPLICATIONS: Both the intubating laryngeal mask airway Fastrach and the Trachlight lightwand attenuate the hemodynamic stress response to tracheal intubation compared with the Macintosh laryngoscope in hypertensive, but not in normotensive, anesthetized paralyzed patients.

Aged↗
PubMed2003

Hemodynamic interactions of propofol and dantrolene in chronically instrumented dogs.

UNLABELLED: The hemodynamic interaction of dantrolene, a specific drug for malignant hyperthermia, and propofol which appears to be safe in malignant hyperthermia-susceptible patients, has not been investigated. We performed this study to examine the hemodynamic actions of dantrolene at a therapeutic dose during propofol anesthesia. Ten dogs were chronically instrumented for the measurements of systemic and coronary hemodynamics. The dogs were assigned to receive propofol with vehicle or dantrolene in a random manner on separate experimental days. Propofol significantly decreased mean arterial blood pressure, left ventricular systolic and end-diastolic pressure, the maximal rate of increase in left ventricular pressure, and left ventricular regional segment shortening. Coronary blood flow (CBF) was unchanged but coronary vascular resistance (CVR) decreased. Dantrolene reversed the decrease in mean arterial blood pressure and left ventricular systolic pressure caused by propofol, and significantly increased heart rate. However, left ventricular end-diastolic pressure, cardiac output, maximal rate of increase in left ventricular pressure, and segment shortening were unchanged. CBF was significantly increased with a decrease in CVR. These results suggest that dantrolene reverses the hypotensive action produced by propofol and causes an increase in CBF with a decrease in CVR, but does not significantly change the negative inotropic effects. Thus, dantrolene exerts favorable hemodynamic effects during propofol anesthesia. IMPLICATIONS: Our study suggests that dantrolene reverses the hypotensive action produced by propofol and causes an increase in coronary blood flow with a decrease in coronary vascular resistance, but does not significantly change the negative inotropic effects.

Anesthetics, Intravenous↗
PubMed2005

Hemodynamic responses to etomidate on induction of anesthesia in pediatric patients.

Etomidate is often used for inducing anesthesia in patients who have limited hemodynamic reserve. Using invasive hemodynamic monitoring, we studied the acute effects of a bolus of etomidate during induction of anesthesia in children. Twelve children undergoing cardiac catheterization were studied (mean age, 9.2 +/- 4.8 yr; mean weight, 33.4 +/- 15.4 kg); catheterization procedures included device closure of secundum atrial septal defects (n = 7) and radiofrequency catheter ablation procedures for supraventricular tachycardia (n = 5). Using IV sedation, a balloon-tipped pulmonary artery catheter was placed to measure intracardiac and pulmonary artery pressures and oxygen saturations. Baseline measurements were recorded and then repeated after a bolus of IV etomidate (0.3 mg/kg). For the entire group, no significant changes in right atrial, aortic, or pulmonary artery pressure, oxygen saturations, calculated Qp:Qs ratio or systemic or pulmonary vascular resistance were detected after the bolus dose of etomidate. The lack of clinically significant hemodynamic changes after etomidate administration supports the clinical impression that etomidate is safe in children. Further research is needed to determine the hemodynamic profile of etomidate in neonates and in pediatric patients with severe ventricular dysfunction and pulmonary hypertension.

Adolescent↗
PubMed2006

A comparison of dexmedetomidine versus conventional therapy for sedation and hemodynamic control during carotid endarterectomy performed under regional anesthesia.

The properties of dexmedetomidine (DEX) that result in titratable sedation and sympathetic modulation suggest that it would be suitable for use during carotid endarterectomy (CEA) performed under regional anesthesia. We performed a randomized, double-blind study in 56 patients having CEA under regional anesthesia and compared hemodynamic control using DEX versus a conventional sedation technique using midazolam and fentanyl standard (STD). Sedation was titrated to a Ramsay Sedation Score of 2-4 in both groups. The primary outcome was the number of pharmacological interventions required to treat deviations of arterial blood pressure and heart rate outside of predetermined limits. We also compared recovery hemodynamic profiles, patient satisfaction, and adverse cardiac and neurological events. There was no difference in the overall rate of hemodynamic interventions (DEX 80% versus STD 79%; P = 1.0). However, the nature of interventions differed in that patients in the DEX group were less likely to require treatment for hypertension and/or tachycardia (DEX 40% versus STD 72%; P = 0.03). The number of interventions per patient for hypertension and/or tachycardia was also lesser in the DEX group (P = 0.02). There were no significant differences in the numbers of patients needing intraoperative treatment for hypotension or bradycardia or in the need for intraarterial shunting. In the postanesthesia care unit, more patients in the DEX group required hemodynamic drug interventions (DEX 11, 44%, versus STD 4, 14%; P = 0.03). These were primarily for hypotension (DEX 7, 28% versus STD 3, 11%; P = 0.16). The number of patients requiring no additional pain relief in the postanesthesia care unit was significantly larger for patients in the DEX group (DEX 18, 72% versus STD 11, 38%; P = 0.027). DEX provides an acceptable alternative, without superiority to standard techniques for sedation during awake CEA.

Aged↗
PubMed1995

Blood pressure monitoring in feeding arteries of cerebral arteriovenous malformations during embolization: a preventive role in hemodynamic complications.

To study the hemodynamics of arteriovenous malformations and to avoid hemodynamic complications during and after artificial embolization, we measured arterial blood pressures in 21 feeders in 14 patients through a microcatheter system. Before embolization, the pressures were significantly low in feeders with branches terminating in the malformation (terminal divided branches) and comparatively low in arteriovenous malformations with rapid blood flow through the malformation. The pressures in feeders with brain-nutrifying branches distal to the nidus (transient branches) were significantly high. Therefore, transient branches might be distinguishable from terminal divided branches with the use of feeder pressure monitoring. A hemorrhagic complication occurred in one patient. The feeder pressure in this patient was low before embolization and showed the maximum change among the patients after embolization. It seems that the lower the feeder pressure, the more likely complications are to occur, owing to remarkable hemodynamic alterations. Feeder pressure monitoring may be useful for preventing hemodynamic complications, especially when angiographic findings show feeding arteries giving off terminal divided or transient branches or rapid blood flow through the malformation.

Adolescent↗
PubMed2004

Pretreatment and posttreatment evaluation of hemodynamic and metabolic parameters in intracranial dural arteriovenous fistulae with cortical venous reflux.

OBJECTIVE: Retrograde drainage into the cortical veins results in poor outcome in patients with an intracranial dural arteriovenous fistula. However, the pathophysiological features of dural arteriovenous fistulae remain obscure. This study aimed to clarify hemodynamic and metabolic conditions in these patients using positron emission tomography. METHODS: This study included eight patients with an intracranial dural arteriovenous fistula. All patients had cortical venous reflux, as demonstrated by angiography. Regional cerebral blood flow (rCBF), regional cerebral blood volume (rCBV), regional cerebral metabolic rate for oxygen, and regional oxygen extraction fraction (rOEF) were measured before and after surgical or endovascular treatment using positron emission tomography. RESULTS: Pretreatment positron emission tomographic studies revealed that all patients had abnormal hemodynamic and metabolic parameters in the area that was drained by the involved cortical veins. A severe increase in rCBV was noted in seven of the eight patients. A significant decrease in rCBF also was observed in all eight patients. A negative correlation was observed between rCBF and rCBV. Three patients had an elevated rOEF. Oxygen metabolism was impaired in seven patients. All patients underwent successful treatment. Follow-up studies demonstrated significant improvements in rCBF, rCBV, and regional cerebral metabolic rate for oxygen. The improvement in regional cerebral metabolic rate for oxygen varied among the patients. Normalization of rOEF also was confirmed in three patients who had increased rOEF before the treatment. CONCLUSION: The present results suggest that hemodynamic and metabolic characteristics vary widely among patients with cortical venous reflux. It is essential to precisely evaluate hemodynamic and metabolic conditions to predict their outcomes and therapeutic effects.

Adult↗
PubMed2003

Hemodynamic and hormonal effects of beraprost sodium, an orally active prostacyclin analogue, in patients with secondary precapillary pulmonary hypertension.

Earlier studies have shown that administration of beraprost sodium (BPS), an orally active prostacyclin analogue, improves hemodynamics in patients with primary pulmonary hypertension (PH), but it is not known whether BPS has beneficial effects in secondary precapillary PH. The present study investigated the hemodynamic and hormonal parameters of 18 patients with secondary precapillary PH (8 patients with chronic thromboembolic PH, 7 with collagen vascular disease, and 3 with residual PH after surgery for atrial septal defect). Hemodynamics were repeatedly measured by right heart catheterization. Treatment with BPS improved New York Heart Association (NYHA) functional class in 10 of the 18 patients and significantly decreased pulmonary vascular resistance by 17% (12.9+/-1.1 to 10.7+/-1.2 Wood units, p<0.01). Circulating brain natriuretic peptide and uric acid significantly decreased from 246+/-61 to 215+/-65 pg/ml and from 6.5+/-0.6 to 5.3+/-0.3 mg/dl, respectively. In summary, BPS therapy improved NYHA functional class, hemodynamics, and hormonal parameters in patients with secondary precapillary PH. Thus, oral administration of BPS may be a new therapeutic strategy for the treatment of secondary precapillary PH.

Administration, Oral↗
PubMed2006

Hemodynamic and clinical correlates of endothelin-1 in chronic thromboembolic pulmonary hypertension.

BACKGROUND: In non-thromboembolic pulmonary hypertension, endothelin (ET)-1 levels are increased and correlate with the hemodynamic severity of the disease. Whether such correlations exist in chronic thromboembolic pulmonary hypertension (CTEPH) is unknown, nor whether ET-1 levels correlate with hemodynamic outcome after pulmonary endarterectomy (PEA). METHODS AND RESULTS: ET-1 levels were determined by ELISA. ET-levels were increased in 35 CTEPH patients (1.62+/-0.21 pg/ml) compared with healthy controls (n=11: 0.75+/-0.06 pg/ml, p<0.02). ET-1 levels correlated (all p<0.0001) with mean pulmonary artery pressure (mPAP) (r=0.70), cardiac index (r=-0.76), total pulmonary resistance (r=0.72), mixed venous oxygen saturation (r=-0.87), and the distance walked in the 6-min walk test (r=-0.59; p<0.005; n=23). Three months after PEA, ET-1 levels had decreased (p<0.002), and were similar between patients with and without residual pulmonary hypertension (p=0.4). Preoperative ET-1 levels, however, were higher in patients with bad postoperative outcome; that is, patients who either died because of persistent pulmonary hypertension or had residual pulmonary hypertension after PEA (2.68+/-0.48 pg/ml, and 1.13+/-0.15 pg/ml, respectively; p<0.002). The levels also correlated with hemodynamic outcome after PEA (mPAP: r=0.67, p<0.0001). By receiver-operator characteristic curve analysis, ET-1>1.77 pg/ml detected a bad postoperative outcome with a sensitivity and specificity of 79% and 85%, respectively, and a likelihood ratio of 5.2. CONCLUSION: ET-1 levels in CTEPH closely correlated with the hemodynamic and clinical severity of disease in a large cohort of patients. Preoperative ET-1 levels may be useful for better identification of patients at risk for persistent pulmonary hypertension after PEA.

Adolescent↗
PubMed1983

Hemodynamic correlates of vectorcardiographic QRS loops in pure mitral stenosis.

The hemodynamic correlates of the vectorcardiographic types of right ventricular hypertrophy (RVH) according to Chou and Helm and those with normal QRS loop in the horizontal plane of Frank system were analyzed in 100 patients with pure mitral stenosis. All underwent right and left heart catheterization. Additionally, coronary arteriography was done on 16 whose ages were above 40. Type A RVH was associated with the most severe hemodynamic alterations with markedly elevated total pulmonary vascular resistance (TPVR), mean pulmonary artery pressure (MPAP), peak right ventricular pressure (RRVP) and the smallest mitral valve area (MVA). The severity of these parameters were to a lesser degree obtainable in type C but with no significant difference from type A (p greater than 0.05). However, types A and C were clearly separated from type B and normal QRS loop (p less than 0.05). Type B RVH and normal QRS loop showed milder hemodynamic changes and were not significantly different (p greater than 0.05). Our results indicate that in pure mitral stenosis the development of RVH is from a normal loop into type B, C and A reflecting an increasing severity of hemodynamic changes which affect the right ventricle. This order of development is different from the traditional view.

Adolescent↗
PubMed1983

Effects of high salt intake on hemodynamic responses to isometric exercise in normotensive subjects and in patients with essential hypertension.

Hemodynamic responses to isometric exercise were compared between 9 normotensive subjects (NT) and 16 patients with essential hypertension (EH) before and during high salt intake. The subjects were hospitalized and placed on a diet containing 6g of salt per day. Baseline hemodynamic studies were carried out on supine subjects before and 3 min after isometric exercise (30% of the maximal voluntary handgrip). Plasma concentration of norepinephrine (PNE) was also measured. Brachial arterial pressure was directly recorded and cardiac output (CO) was measured by the dye-dilution technique using a cuvette. The hemodynamic studies were repeated on the 5th day of a high salt diet (16g of salt per day). Retention of sodium was calculated on a daily basis by measuring the actual intake of sodium and 24-hour urinary excretion of sodium. Pressor responses to isometric exercise were significantly greater in the EH than in the NT group. Patterns of hemodynamic responses were different in the 2 groups, i.e., the elevation of arterial pressure was maintained by an increase in CO in the NTs, while it was maintained by increases in CO and total peripheral vascular resistance (TPR) in the EHs. The increase in CO was significantly greater in the NT than in the EH group [15 +/- 3 (mean +/- SE) vs 7 +/- 1%, p less than 0.05]. Although the salt loading reduced heart rate similarly in both groups (-9.0 +/- 2.1, p less than 0.01, in the NTs and -11.9 +/- 2.9%, p less than 0.01, in the EHs), the high salt diet did not significantly alter mean arterial pressure (MAP), CO or TPR in either group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1983

Hemodynamics and the baroreflex function in borderline hypertension.

The hemodynamics and the baroreflex function were studied and compared between patients with borderline and established hypertension. 1) As compared to patients with established hypertension, the heart rate, the cardiac output and the left ventricular ejection fraction were higher in patients with borderline hypertension in the young group, but these characteristics were not found in the patients of the middle-aged group. 2) In regard to the cardiac output and the total peripheral resistance, patients with borderline hypertension predominantly showed a high cardiac output, especially in the young group, while patients with established hypertension predominantly showed a high total peripheral resistance, especially in the middle-aged group. 3) At higher and lower blood pressure levels during one day, no difference of hemodynamic pattern was observed in the same subjects. 4) The hemodynamic response to exercise, isoproterenol and noradrenaline was greatest in the borderline hypertensives of the young group. 5) The baroreceptor slope decreased in the order of normal subjects, borderline hypertensives and established hypertensives. It decreased with age in each group. The hemodynamics and the baroreflex function in borderline hypertensives differed slightly between the young and the middle-aged groups. Although the borderline hypertension in the middle-aged group is considered to be a pre-stage of established hypertension, detailed analysis of case histories may be required to assess how borderline hypertension develops into established hypertension in the young group.

Adult↗
PubMed1989

[Effects of levocarnitine chloride (LC-80) on hemodynamics and myocardial metabolism in anesthetized open-chest dogs under normoxic or hypoxic conditions].

The effects of LC-80, infused intravenously at a rate of 10 mg/kg/min for 30 min, on hemodynamics and myocardial metabolism were investigated in anesthetized open-chest dog preparations under a normal oxygen tension of arterial blood (PaO2) ranging from 100 to 120 mmHg or low PaO2 ranging from 40 to 50 mmHg. (1) Normal PaO2 + High free fatty acidemia (HFFA): HFFA was produced by the intravenous infusion of Intralipid at a rate of 0.1 ml/kg/min after the rapid intravenous injection of 500 U/kg of heparin. Under this experimental condition, no significant changes in hemodynamics and myocardial metabolism were observed in both the LC-80 treated group and control group. (2) Low PaO2 + HFFA: Under this condition, there was no significant difference in hemodynamics between the LC-80 treated group and the control group, and the myocardial function in both groups tended to decrease. However, the increase in the coronary flow of the LC-80 treated group tended to be slight as compared with that of the control group. On the other hand, the decrease in the arterio-coronary venous difference of lactate was significantly less in the LC-80 treated group as compared to that in the control group. Furthermore, the reduction in myocardial redox potential (delta Eh) of the LC-80 treated group tended to be slight as compared with that of the control group. (3) Low PaO2 + HFFA + stress load: The hemodynamic responses (heart rate, left ventricular pressure, max dP/dt and cardiac work) to isoproterenol-induced stress were slightly but not significantly better in the LC-80 treated group than in the control group. While myocardial lactate production and the reduction of delta Eh in both groups became more prominent under this experimental condition, their degrees were apparently less in the LC-80 treated group as compared to those in the control group. These results suggest that LC-80 may have an improving effect on the anaerobic myocardial metabolism under anaerobic conditions such as hypoxia or stress load.

Animals↗
PubMed1990

[Responses of plasma eicosanoids and hemodynamics to myocardial ischemia and the salutary effect of calcium entry blocker].

The responses of eicosanoids to acute myocardial ischemia induced by either exercise stress testing (EX) or percutaneous transluminal coronary angioplasty (PTCA) were investigated in 23 patients with effort angina pectoris (EAP). EX was useful procedure to determine the therapeutic plan in each cases, and PTCA is the novel therapeutic operation for EAP. The relations between these metabolites and either hemodynamics or coronary circulation were then evaluated. The effect of the calcium entry blocker nisoldipine (oral administration of 5 mg) was also studied in 10 patients with EAP. The plasma levels of thromboxane B2 (TXB2), 6-keto-prostaglandin F1 alpha (6KPGF1 alpha) and leukotriene C4 (LTC4) were determined by radioimmunoassay. in arterial and coronary sinus blood samples before and immediately after acute myocardial ischemia. The changes in hemodynamics and coronary circulation during exercise stress testing were assessed by measuring direct brachial artery pressure, cardiac output by the dye dilution method and coronary sinus flow by the thermodilution method. The TXB2/6KPGF1 alpha ratio in coronary sinus blood significantly increased after ischemia in both EX and PTCA, but there was no significant change in LTC4 levels of coronary sinus blood immediately after acute ischemia. The 6KPGF1 alpha levels in both arterial and coronary venous blood were significantly correlated to coronary perfusion pressure and mean brachial artery pressure. Arterial LTC4 levels tended to correlate to mean brachial artery pressure and coronary sinus flow. Nisoldipine improved the ischemic electrocardiography response to EX. Nisoldipine also significantly increased arterial 6KPGF1 alpha at peak exercise. It significantly decreased brachial artery pressure, pressure rate product (PRP), mean coronary sinus pressure and coronary vascular resistance both at rest and peak exercise. The response of PRP significantly correlated with the response of arterial 6KPGF1 alpha. These results suggest: 1 The imbalance of the TXB2/6KPGF1 alpha ratio may be induced more rapidly than LTC4. 2 PGI2 and LTC4 may have some role in the regulation of hemodynamics and coronary circulation during acute myocardial ischemia. 3 Nisoldipine may ameliorate myocardial ischemia through improvement of systemic hemodynamics and prostaglandin metabolism apart from through direct action on the heart.

6-Ketoprostaglandin F1 alpha↗