scholarly journals THE INFLUENCE OF EPINEPHRIN UPON THE CORONARY CIRCULATION OF THE MONKEY

1915 ◽  
Vol 21 (4) ◽  
pp. 330-336 ◽  
Author(s):  
Henry G. Barbour ◽  
Alexander L. Prince

Decrease in coronary flow was the constant response of freshly isolated monkey hearts to epinephrin. These hearts were perfused with autogenous hirudinized blood diluted with Locke solution. The results were constant at high or low perfusion pressures, in beating or resting hearts, and with all adequate doses. Increased coronary flow was obtained constantly in rabbit hearts under identical conditions. In the light of previous work upon isolated human coronary arteries, the general conclusion is drawn that, while actively dilating the coronary vessels in the dog, cat, rabbit, ox, sheep, and pig, epinephrin constricts the coronary vessels in man and the monkey. The coronary arteries of the last two species are presumably supplied with constrictor nerves of true sympathetic (thoracicolumbar) origin.

1987 ◽  
Vol 129 (1) ◽  
pp. 107-123 ◽  
Author(s):  
A. P. Farrell

A preparation was developed to perfuse the coronary circulation in working hearts from rainbow trout (Salmo gairdneri Richardson). The preparation was used to examine pressure-flow relationships for the coronary circulation as the heart generated physiological and subphysiological work loads. Coronary vascular resistance increased exponentially as coronary flow rate decreased. Coronary resistance was also influenced by cardiac metabolism and acclimation temperature. When heart rate was increased, extravascular compression increased in coronary resistance. Direct vasoconstriction of the coronary vessels, produced by injections of adrenaline into the coronary circulation, was temperature-dependent.


1969 ◽  
Vol 47 (5) ◽  
pp. 421-425 ◽  
Author(s):  
Edilberto C. Torres ◽  
Giorgio Brandi

A method is described by which it is possible to study the selective effects of vasoactive drugs on the small vessels of the coronary circulation of the dog. We incorporated xenon-133 with different drugs and derived the flow/volume ratios from the rate of fall of radioactivity at the injection site. Ratios were consistently reduced by angiotensin (−37%), pitressin (−40%), and propranolol (−13%), and were increased by dipyridamole (+23%), nitroglycerine (+14%), isoproterenol (+30%), adrenaline (+30%), and noradrenaline (+25%), indicating that these agents have an effect on the small coronary vessels. Ratios were unaltered by phenylephrine and by combinations of propranolol with adrenaline or noradrenaline, suggesting that alpha receptor sites may be absent from the small vessel bed under study.


1962 ◽  
Vol 202 (4) ◽  
pp. 616-618 ◽  
Author(s):  
Cecil E. Cross ◽  
Robert W. Oblath

The atherogenic regimen imposed upon the animals studied here resulted in several distinct abnormalities of the coronary circulation. The structure of the coronary arteries was modified by extensive atheromatous deposits. During control states before the administration of vasoactive drugs, coronary flow per unit of net propulsive force and heart weight was unvaried or increased. The ability of the atheromatous coronary tree to increase or decrease its vasomotor tonus was markedly curtailed. The abnormalities mentioned here were proportional with the severity of the atherogenic regimen.


2006 ◽  
Vol 29 (5) ◽  
pp. 211-214 ◽  
Author(s):  
Haruhiko Date ◽  
Takuroh Imamura ◽  
Takeshi Ideguchi ◽  
Junji Kawagoe ◽  
Takahiro Sumi ◽  
...  

2021 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
E Kalinina ◽  
A Zagatina ◽  
N Zhuravskaya ◽  
D Shmatov

Abstract Funding Acknowledgements Type of funding sources: None. Background There is a high prevalence of coronary artery disease (CAD) in the elderly population. However, symptoms of CAD are often non-specific. Dyspnoe, non-anginal pains are among the main symptoms in older patients. Exercise tests are of limited feasibility in these patients, due to neuro-muscular weakness, physical deconditioning, and orthopaedic limitations. Pharmacological tests often are contraindicated in a substantial percentage of elderly patients. Some recent studies indicate using local flow acceleration during routine echocardiography has prognostic potential for coronary artery assessments without stress testing. The aim of the study was to define the prognostic value of coronary artery ultrasound assessment in patients ≥75 years old. Methods This is a prospective cohort study. Patients ≥ 75 years old who underwent routine echocardiography with additional scans for coronary arteries over a period of 24 months were included in the study. The study group consisted of 80 patients aged 75-90 years (56 women; mean age 79 ± 4). Initial exams were performed for other reasons, primarily for arterial hypertension. Fifteen patients had known CAD. Death, non-fatal myocardial infarction (MI), and revascularization were defined as major adverse cardiac events (MACE). All patients were followed up with at a median of 32 months. Results There were 34 patients with high local velocities in the left coronary artery. Eight deaths, two non-fatal myocardial infarctions occurred, and 13 revascularizations were performed. With a ROC analysis, a coronary flow velocity >110 cm/s was the best predictor for risk of death (area under curve 0.84 [95% CI 0.74–0.92]; sensitivity 75%; specificity 88%). Only the maximal velocity in proximal left-sided coronary arteries was independently associated with death (HR 1.03, 95% CI 1.01; 1.05; p < 0.002), or death/MI (HR 1.03, 95% CI 1.01; 1.04; p < 0.0001). The cut-off value of 66 cm/s was a predictor of all MACE (area under curve 0.87 [95% CI 0.77–0.94]; sensitivity 80%; specificity 86%). Any causes of death or MI occurred more frequently in patients with velocities of >66 cm/s (27% vs. 2%; p < 0.002). The rates of MACE were 58.0% vs. 2%; p < 0.0000001, respectively. Conclusion The analysis of coronary flow in the left coronary artery during echocardiography can be used as a predictor of outcomes in elderly patients. Maximal velocities in proximal left-sided coronary arteries is independently associated with further death or myocardial infarction.


2008 ◽  
Vol 295 (2) ◽  
pp. H482-H490 ◽  
Author(s):  
Christina Kolyva ◽  
Jos A. E. Spaan ◽  
Jan J. Piek ◽  
Maria Siebes

A novel single-point technique to calculate local arterial wave speed ( SPc) has recently been presented and applied in healthy human coronary arteries at baseline flow. We investigated its applicability for conditions commonly encountered in the catheterization laboratory. Intracoronary pressure (Pd) and Doppler velocity ( U) were recorded in 29 patients at rest and during adenosine-induced hyperemia in a distal segment of a normal reference vessel and downstream of a single stenosis before and after revascularization. Conduit vessel tone was minimized with nitroglycerin. Microvascular resistance (MR) and SPc were calculated from Pd and U. In the reference vessel, SPc decreased from 21.5 m/s (SD 8.0) to 10.5 m/s (SD 4.1) after microvascular dilation ( P < 0.0001). SPc was substantially higher in the presence of a proximal stenosis and decreased from 34.4 m/s (SD 18.2) at rest to 27.5 m/s (SD 13.4) during hyperemia ( P < 0.0001), with a concomitant reduction in Pd by 20 mmHg and MR by 55.4%. The stent placement further reduced hyperemic MR by 26% and increased Pd by 26 mmHg but paradoxically decreased SPc to 13.1 m/s (SD 7.7) ( P < 0.0001). Changes in SPc correlated strongly with changes in MR ( P < 0.001) but were inversely related to changes in Pd ( P < 0.01). In conclusion, the single-point method yielded erroneous predictions of changes in coronary wave speed induced by a proximal stenosis and distal vasodilation and is therefore not appropriate for estimating local wave speed in coronary vessels. Our findings are well described by a lumped reservoir model reflecting the “windkesselness” of the coronary arteries.


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