Intraventricular blood pressures in the chicken

1960 ◽  
Vol 198 (1) ◽  
pp. 153-154 ◽  
Author(s):  
H. E. Bredeck

Direct heart punctures were made in two groups of unanesthetized chickens to determine the left and right intraventricular blood pressures. One group was composed of nonlaying birds 28–30 weeks old and the other of laying hens 65–67 weeks of age. Heart rates and the respiratory influence on pressure were also measured. Average pressures obtained were 144/0 and 21/ - 1 mm Hg for the left and right ventricle, respectively. Respiratory efforts caused a mean fluctuation in systolic pressure of approximately 8 mm Hg in the left ventricle and 4 mm Hg in the right. With the exception of the right ventricular diastolic blood pressure, there were no significant pressure or pulse rate differences between the two groups. The heart rate and left ventricular pressure were found to be significantly correlated ( P < .01) in both groups of birds.

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Naoki Fujimoto ◽  
Keishi Moriwaki ◽  
Issei Kameda ◽  
Masaki Ishiyama ◽  
Taku Omori ◽  
...  

Introduction: Isometric handgrip (IHG) training at 30% maximal voluntary contraction (MVC) lowers blood pressure in hypertensive patients. Impacts of IHG exercise and post-exercise circulatory arrest (PECA), which isolates metaboreflex control, have been unclear in heart failure (HF). Purpose: To investigate the impacts of IHG exercise and PECA on ventricular-arterial stiffness and left ventricular (LV) relaxation in HF with preserved (HFpEF) and reduced ejection fraction (HFrEF). Methods: We invasively obtained LV pressure-volume (PV) loops in 20 patients (10 HFpEF, 10 HFrEF) using conductance catheter with microtip-manometer during 3 minutes of IHG at 30%MVC and 3 minutes of PECA. Hemodynamics and LV-arterial function including LV end-systolic elastance (Ees) by the single-beat method, effective arterial elastance (Ea), and time constant of LV relaxation (Tau) were evaluated every minute. Results: At rest, HFpEF had higher LV end-systolic pressure (ESP) and lower heart rate than HFrEF with similar LV end-diastolic pressure (EDP). The coupling ratio (Ees/Ea) was greater in HFpEF than HFrEF (1.0±0.3 vs. 0.6±0.3, p<0.01). IHG for 3minutes similarly increased heart rate in HFpEF (by 10±8 bpm) and HFrEF (by 14±6 bpm). IHG also increased end-diastolic and LVESP (134±21 vs. 158±30 mmHg and 113±25 vs. 139±25 mmHg) in both groups (groupхtime effect p≥0.25). In HFpEF, Ees, Ea and Ees/Ea (1.0±0.3 vs. 1.1±0.4) were unaffected during IHG. In HFrEF, IHG induced variable increases in Ea. LV end-systolic volume and the ESPV volume-axis intercept were larger, and Ees at IHG 3 rd min was greater (1.30±0.7 vs. 3.1±2.1 mmHg/ml, p<0.01) than baseline, resulting in unchanged Ees/Ea at IHG 3 rd min (0.6±0.3 vs. 0.8±0.4, p≥0.37). Tau was prolonged only in HFrEF during IHG and was returned to the baseline value during PECA. During the first 2 minutes of PECA, LVESP was lower than that at IHG 3 rd min only in HFpEF, suggesting less metaboreflex control of blood pressure in HFpEF during IHG. Conclusions: IHG exercise at 30%MVC induced modest increases in LV end-systolic and end-diastolic pressures in HFpEF and HFrEF. Although the prolongation of LV relaxation was observed only in HFrEF, the ventricular and arterial coupling was maintained throughout the IHG exercise in both groups.


1988 ◽  
Vol 255 (3) ◽  
pp. H503-H513 ◽  
Author(s):  
R. B. Schuessler ◽  
T. E. Canavan ◽  
J. P. Boineau ◽  
J. L. Cox

In open-chest dogs, blood pressure was regulated by titrating doses of phenylephrine and nitroprusside to determine its effect on heart rate and pacemaker location. Changes in blood pressure correlated with changes in heart rate (r = 0.86). Activation time mapping demonstrated multicentric atrial activation, with a site of origin-rate relationship. The fastest pacemakers were located in the most cranial regions and slowest in the most caudal areas. In this chloralose-morphine anesthetized model, autonomic blockade with atropine and propranolol suggests that acute baroreflex-induced changes in heart rate were mediated exclusively by either increased sympathetic or parasympathetic tone and were not associated with inhibition of the opposite system. Division of right and left thoracic cardiac nerves indicated the left sympathetics participated in the baroreflex in 50% of the animals and the left parasympathetics in 90% of the animals. Both the right sympathetics and parasympathetics were active in the baroreflex in all animals. The data demonstrate that physiological heart rate response is regulated through an extensive system of right atrial pacemakers modulated by both left and right efferent cardiac nerves.


Author(s):  
W.J. Du Plooy ◽  
P.J. Schutte ◽  
J. Still ◽  
L. Hay ◽  
C.P. Kahler

The stability of cardiodynamic and some blood parameters during a slow, continuous infusion of a combination of ketamine and diazepam is reported. Contractility (dP/dt), myocardial relaxation (Tln), left ventricular end-diastolic pressure (LVEDP), left ventricular systolic pressure (LVSP), arterial blood pressure and certain blood parameters were assessed in 3 male and 3 female juvenile baboons (Papio ursinus). Anaesthesia was induced with 15 mg/kg ketamine IM and maintained with a continuous IV infusion (40-60 mℓ/h) of ketamine and diazepam. The mixture consisted of 2 mℓ ketamine (100 mg/mℓ), 2 mℓ diazepam (5 mg/mℓ) and 50 mℓ saline. A period of 75 + 10 min was allowed for preparation of the animals, after which lead II of the ECG, femoral artery blood pressure and left ventricular pressure were recorded at 15-min intervals for a period of 2 h: the total duration of anaesthesia was 195 min. Arterial blood samples were analysed at 30-min intervals for blood gases, electrolytes, glucose and insulin. Left ventricular parameters were derived from the left ventricular pressure curve. Tln, LVSP and LVEDP showed small fluctuations. Contractility decreased (p < 0.037) at the 195-min interval. No arrhythmias or ECG changes were seen, while blood pressure decreased gradually. Serum calcium concentration decreased and blood glucose levels increased gradually over time. Anaesthesia and analgesia were sufficient and no other drugs were necessary. The animals appeared sedated and dazed 60-80 min after the procedure. A continuous infusion of a combination of ketamine and diazepam for a duration of 150 min can provide stable anaesthesia for cardiodynamic measurements.


Author(s):  
G.F. Stegmann

Anaesthesia of 2 five-year-old femaleAfrican elephants (Loxodonta africana) was required for dental surgery. The animals were each premedicated with 120 mg of azaperone 60 min before transportation to the hospital. Before offloading, 1 mg etorphine was administered intramuscularly (i.m.) to each elephant to facilitate walking them to the equine induction / recovery room. For induction, 2 mg etorphine was administered i.m. to each animal. Induction was complete within 6 min. Surgical anaesthesia was induced with halothane-in-oxygen after intubation of the trunk. During surgery the mean heart rate was 61 and 45 beats / min respectively. Systolic blood pressures increased to 27.5 and 25.6 kPa respectively, and were treated with intravenous azaperone. Blood pressure decreased thereafter to a mean systolic pressure of 18.1 and 19.8 kPa, respectively. Rectal temperature was 35.6 and 33.9 oC at the onset of surgery, and decreased to 35.3 and 33.5 oC, respectively, at the end of anaesthesia. Etorphine anaesthesia was reversed with 5mg diprenorphine at the completion of 90 min of surgery.


1946 ◽  
Vol 84 (6) ◽  
pp. 549-558 ◽  
Author(s):  
S. C. Wang ◽  
E. E. Painter ◽  
R. R. Overman

Repeated determinations of the circulation time by the fluorescein method were made in normal and shocked dogs. In normal animals the circulation time ranges from 9 to 16 seconds with an average of 12.6 seconds. In traumatic shock the circulation time is invariably prolonged. For prognosis in the traumatized animal two determinations of fluorescein circulation time separated by an interval of 1 hour are essential. If the second circulation time is longer than the first and both are over 30 seconds, the animal will not survive without therapy. On the other hand, if the second circulation time is below 25 seconds or is considerably shorter than the first, the prognosis is good. In many of these experiments the change in circulation time appeared to be the earliest index of eventual recovery or death. It gave a clue to the fate of the animal when no decisive judgment could be made from the blood pressure and heart rate. In three dogs the cyanide and fluorescein circulation times were compared during shock. It was found that the cyanide circulation time, though increased in shock, remained at a fairly constant value while over the same period the fluorescein circulation time showed progressive changes. This discrepancy between the cyanide and fluorescein methods may be explained by the fact that the former does not include the minute peripheral systemic circulation. Since the study of shock is concerned with tissue anoxia and is primarily a phenomenon of the failure of the peripheral circulation, it is important to choose procedures such as the fluorescein method as a measure of the condition of the peripheral vascular system.


1993 ◽  
Vol 265 (6) ◽  
pp. H2099-H2109 ◽  
Author(s):  
R. Krams ◽  
L. K. Soei ◽  
E. O. McFalls ◽  
E. A. Winkler Prins ◽  
L. M. Sassen ◽  
...  

Regional end-systolic pressure-segment length relationships (ESPSLR) were used to compare the degree of right and left ventricular stunning induced by a 10-min occlusion of the left anterior descending coronary artery and the response to subsequent atrial pacing (50 beats/min above intrinsic heart rate) without and with dobutamine (2 micrograms.kg-1.min-1) in nine anesthetized open-chest pigs. From the ESPSLR, the slope (Ees) (at 100 mmHg for the left and 25 mmHg for the right ventricle) and the total area of the pressure-length relationship (PLA) were determined. From the latter, the distribution into external work (EW) and potential energy (PE) as well as the efficiency of energy transfer (EET = EW/PLA) were calculated. In both the stunned left and right ventricular myocardium Ees and EW were reduced according to the same linear regression equations (delta Ees = 0.7 Ees,baseline - 11.4, r2 = 0.86 and delta EW = 0.4 EWbaseline + 2.3, r2 = 0.67), where Ees,baseline and EWbaseline are Ees and EW at baseline, respectively. EET of the stunned left and right ventricular segments decreased as PLA remained unchanged, due to an increase in PE. EET decreased from 0.84 +/- 0.02 to 0.71 +/- 0.03 (P < 0.05) in the stunned right ventricular segment and from 0.71 +/- 0.02 to 0.44 +/- 0.03 (P < 0.05) in the stunned left ventricular segment. Atrial pacing did not affect EET with respect to stunning levels, whereas the additional infusion of dobutamine restored Ees, EW, and PE and consequently EET to baseline values. In conclusion, the right ventricle is susceptible to stunning. During atrial pacing the EET was lower than expected from the Ees, which could, in agreement with the time-varying elastance concept, be explained by an increase in afterload (a consequence of the decrease in stroke volume). Dobutamine not only increased Ees, EW, and EET but also restored the relationship between Ees and EET in both ventricular stunned segments.


Author(s):  
Nasibeh Yousefzadeh ◽  
Sajad Jeddi ◽  
Asghar Ghasemi

Background and Objective: All three isoforms of nitric oxide (NO) synthase (NOS) are targets for thyroid hormones in cardiovascular system. The aim of this study was to assess effects of hypoand hyperthyroidism on inducible (iNOS), endothelial (eNOS), and neural (nNOS) NOS levels in aorta and heart tissues of male rats. Methods: Rats were divided into control, hypothyroid, and hyperthyroid groups; hypo- and hyperthyroidism were induced by adding propylthiouracil (500 mg/L) and L-thyroxine (12 mg/L) to drinking water for a period of 21 days, respectively. At day 21, systolic blood pressure, heart rate, left ventricular developed pressure (LVDP), peak rate of positive and negative (±dp/dt) changes in left ventricular pressure as well as NO metabolites (NOx) and iNOS, eNOS, and nNOS protein levels in aorta and heart were measured. Results: Compared to controls, LVDP and ±dp/dt were lower in both hypo- and hyperthyroid rats. Compared to controls, heart rate and systolic blood pressure were lower in hypothyroid and higher in hyperthyroid rats. NOx levels in the heart of hypothyroid rats were lower (53%) whereas in the heart and aorta of hyperthyroid rats were higher (56% and 40%) than controls. Compared to controls, hypothyroid rats had lower levels of eNOS, iNOS, and nNOS in aorta (16%, 34%, and 15%, respectively) and lower iNOS and higher nNOS in heart tissue (27% and 46%). In hyperthyroid rats, eNOS levels were lower (54% and 30%) and iNOS were higher (63%, and 35%) in the aorta and heart while nNOS was lower in the aorta (18%). Conclusion: Hypothyroidism increased while hyperthyroidism decreased ratio of eNOS/iNOS in aorta and heart; these changes of NOS levels were associated with impaired cardiovascular function.


2021 ◽  
Vol 5 (3) ◽  
pp. 306
Author(s):  
Vicky Agnes Arundy ◽  
Iskandar Fitri ◽  
Eri Mardiani

Heart disease is a condition when the heart is experiencing a disorder. The forms of disturbance that are experienced are usually various. Usually there is a disturbance in the blood vessels of the heart, heart rate, heart cover, or congenital problems. The heart itself is a muscle consisting of four chambers. That is, the first two rooms are located at the top, the atrium (foyer) to the left and right. Then the other two rooms are at the bottom, namely the right and left ventricles. To provide information on how to diagnose the type of disease and how to control heart disease, an application of an expert system that can represent someone who is an expert in their field is needed to provide solutions to this disease problem using the Case-Based Reasoning method with the Sorensen Coeffient approach. The result of this research is the creation of an expert system for diagnosing heart disease using the Case-Based Reasoning method with the Sorensen Coeffient approach which is able to provide solutions to heart disease.Keywords:CBR, Expert system, Heart Disease, Method Sorensen Coeffient.


1979 ◽  
Vol 47 (2) ◽  
pp. 312-318 ◽  
Author(s):  
D. R. Kostreva ◽  
F. A. Hopp ◽  
E. J. Zuperku ◽  
J. P. Kampine

The reflex effects of right and left ventricular distension, mediated by vagal afferents, were studied in mongrel dogs anesthetized with halothane or pentobarbital sodium on heart-lung bypass. Diaphragm electromyogram (D-EMG), systemic blood pressure, and left ventricular cardiogram were all measured during ventricular distension. After bilateral section of the stellate ganglia, distension of the left ventricle produced an apnea, or slowing of respiration and systemic hypotension, without a change in heart rate. A reflex decrease in the amplitude of the D-EMG occurred if the initial breathing rate was high; a decrease in frequency of the D-EMG bursts occurred if the initial rate was low. The left ventricular vagal afferents altering respiration had conduction velocities between 22 and 70 m/s, whereas those causing hypotension had conduction velocities less than 22 m/s. Distension of the right ventricle resulted in a significant tachypnea and systemic hypotension without a change in heart rate. The conduction velocities of the right ventricular vagal afferents causing both tachypnea and hypotension were less than 9 m/s. These reflex changes in respiration and blood pressure elicited by both right and left ventricular distension were eliminated with vagotomy.


1990 ◽  
Vol 69 (1) ◽  
pp. 305-312 ◽  
Author(s):  
D. P. Fitzsimons ◽  
P. W. Bodell ◽  
R. E. Herrick ◽  
K. M. Baldwin

Cardiac myosin P-light chain phosphorylation [P-LC(P)] has been proposed to augment myocardial force production. This study was undertaken to examine the potential for cardiac myosin P-LC(P) for both equivalent heart rate and work load in exercising endurance-trained and nontrained rodents. A 10-wk training protocol elicited a significant reduction in submaximal running O2 uptake while enhancing peak O2 uptake (-17 and 10%, respectively, P less than 0.05). Left ventricular functional index during submaximal exercise, obtained with a high-fidelity Millar ultraminiature pressure transducer, indicated that the trained animals were able to maintain peak left ventricular pressure (LVP) in comparison to their sedentary counterparts, even though both heart rate and rate of LVP development were significantly reduced (P less than 0.05). When expressed on the basis of equivalent submaximal heart rate, peak LVP was augmented in the trained animals. Cardiac myosin P-LC(P) was examined under two conditions known to produce disparate responses in trained vs. sedentary animals. For an equivalent work load, we observed parallel increases in P-LC(P) (20%) and systolic pressure (17%) in both groups, even though the trained animals exhibited significantly lower heart rates (P less than 0.05). For an equivalent heart rate, training evoked a significant increase in systolic pressure (26%, P less than 0.05) and caused a slight increase in P-LC(P) relative to the nontrained controls. Cardiac myosin adenosinetriphosphatase was reduced approximately 10% in the trained animals (P less than 0.05), commensurate with a 2.0-fold increase in the V3 (low adenosinetriphosphatase) isomyosin.(ABSTRACT TRUNCATED AT 250 WORDS)


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