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Anterior left ventricular wall echoes in coronary artery disease. Linear scanning with a single element transducer. Am J Cardiol 1974; 34:652-7. [PMID: 4423832 DOI: 10.1016/0002-9149(74)90152-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Abstract
A multidiscipline group was established at The Pennsylvania State University to design and evaluate mechanical circulatory assist devices and the artificial heart. The group has designed a left ventricular to aortic assist system which consists of a sac-type pump, a synchronization unit, a pneumatic power unit, and appropriate monitoring apparatus. The assist system has been evaluated for long-term circulatory assistance in a series of ten calves. The assist pump was placed in the paracorporeal position. The longest period of continuous pumping was over eight months. The last four calves have had synchronized assist pumping which has permitted prolonged ventricular decompression and assist pump flow rates as high as 10 L/min. Three of these four calves had no evidence of thromboemboli. Additional animal studies will be required before clinical use of such an assist pump system can be safely undertaken.
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4
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Pathogenesis of subendocardial ischemia. Am J Med Sci 1974; 268:3-13. [PMID: 4606889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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6
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[Changes in local myocardial blood circulation following oral administration of a Crataegus extract in non-narcotized dogs]. ARZNEIMITTEL-FORSCHUNG 1974; 24:783-5. [PMID: 4408035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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7
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Nitroglycerin and chromonar on small-vessel blood content of the ventricular walls. THE AMERICAN JOURNAL OF PHYSIOLOGY 1974; 226:838-43. [PMID: 4207222 DOI: 10.1152/ajplegacy.1974.226.4.838] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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8
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Abstract
Phasic red cell velocity and diameters of coronary arterioles, capillaries, and venules were measured in the beating turtle and dog heart using high-speed cinematography with transillumination of the left ventricle. In the turtle, arteriolar red cell velocity was diminished during systole, but during diastole arteriolar inflow increased, especially during the rapid and the slow filling period. Capillary and venule red cell velocity was increased during systole, particularly at the time of ejection; however, during diastole red cell velocity declined and the lowest values occurred during isovolumic relaxation. In dog arterioles, capillaries, and venules, the pattern of red cell velocity was similar. Thus, in the turtle and dog, the peak arteriolar red cell velocity occurred in unison with left coronary artery inflow, and the capillary and venule flow pattern followed that of the coronary sinus. The diameters of arterioles, capillaries, and venules in the turtle ventricle all declined about 34% during systole; similar results were obtained in the dog. Capillary arrangement appeared to be predominantly parallel and cocurrent; however, capillary loops with countercurrent flow were occasionally observed. The data on microvascular phasic red cell velocity are consistent with the macroobservations of reduced coronary artery inflow and enhanced coronary sinus outflow during ventricular contraction. The results demonstrate that the shift in the flow pattern occurs at the transition from arterioles to capillaries.
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9
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Total and regional myocardial blood flow measurements with 25 micron, 15 micron, 9 micron, and filtered 1-10 micron diameter microspheres and antipyrine in dogs and sheep. Circ Res 1974; 34:391-405. [PMID: 4818762 DOI: 10.1161/01.res.34.3.391] [Citation(s) in RCA: 192] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The accuracy of regional myocardial blood flow measurements made with microspheres of different sizes is uncertain. Therefore, we simultaneously injected radioactive microspheres of different sizes into the left atria of dogs and sheep; the microsphere diameters were 25µ, 15µ, 9µ, 1-l0µ, and filtered 1-10µ (most > 7µ). Antipyrine was sometimes simultaneously infused for 15-60 seconds. Myocardial blood flow was altered by hemorrhage, tachycardia, supravalvar aortic constriction, or infusion of methoxamine or adenosine triphosphate; left coronary artery branches were occluded on two occasions. Sometimes the percent of untrapped microspheres was estimated. All sizes of microspheres measured similar total myocardial blood flows when the percent of untrapped microspheres was known. All indicators were distributed identically to the right and left ventricular free walls and septum; ischemic areas had a 1% excess of antipyrine. With any pair of microspheres, the larger had a subendocardial excess except for 25µ microspheres, which were in excess compared with 15µ microspheres in the higher flow layer whether it was subendocardial or subepicardial. The greatest difference for any pair of microspheres was 10.53% of flow in a layer. Antipyrine did not define which size of microspheres measured true regional blood flow, since many previously unemphasized limitations were discovered. Nevertheless, we believe that microspheres 9µ in diameter are probably the best for measuring regional myocardial blood flow.
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10
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Abstract
One of the main branches of the left main coronary artery of normally beating dog hearts was perfused with a silicone elastomer which solidified within the vasculature. Prolonged immersion in increasingly concentrated ethanol and in methyl salicylate rendered the tissue translucent and the vasculature clearly visible. Surfaces were photographed by reflected or transmitted light microscopy, showing large groups of capillaries running parallel to muscle fibers and extending for up to a few centimeters. The arrangement of arteriolar inflows to the capillary network and venular outflows (two to four times as frequent) suggested that functional capillary lengths were 500–1000 μm. Estimates of capillary diameters, presumably at maximal dilatation, were 5.6 ± 1.3 μm. Capillary densities within muscle groups were 3100–3800/mm2, giving intercapillary distances of 19–17.5 μm. With the lesser density value, the capillary surface area is estimated to be 500 cm2/g of myocardium. Inclusion of interfascial spaces lowered the average density to about 2500/mm2. Unbranched capillary lengths averaged 100 μm, with a strongly right-skewed distribution. The anatomic arrangement provides a basis mainly for concurrent flow in neighboring capillaries, and also for some diffusional exchange between inflow and outflow regions.
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11
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Effect of pentrinitrol, nitroglycerin and propranolol on small vessel blood content of the canine myocardium. J Pharmacol Exp Ther 1973; 187:465-74. [PMID: 4770393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
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13
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Beta adrenergic blockade on intramyocardial distribution of coronary blood flow. J Pharmacol Exp Ther 1973; 187:451-64. [PMID: 4149128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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14
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Abstract
Microspheres of different sizes, 125I-labeled antipyrine (I-Ap), and 42KCl or 86RbCl were injected into the aortic inflow of isolated, Langendorff, perfused, nonworking dogs hearts at blood flows of 1.3–4.8 ml/min g−1. After 15 seconds to 5 minutes, the left ventricle was sectioned into about 300 ordered pieces, and the amount of each tracer was determined. For all tracers, the relative density of deposition was generally higher in the endocardial region, except in one heart in which the aortic pressure and the total coronary flow were low. The deposition of 42K and that of I-Ap were essentially similar in three hearts over a large range of regional variation. This finding suggests either that both tracers were distributed in proportion to flow or that a small diminution in relative density of deposition of 42K in high-flow regions due to lower transcapillary extraction was quantitatively similar to a decrease in the residual fraction of I-Ap in these same regions due to faster washout in the first 15–30 seconds after injection. Large microspheres were deposited preferentially in regions of high flow, exaggerating the apparent heterogeneity of regional flows. The distribution of the smaller microspheres was closer to that for I-Ap or 42K.
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15
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Influence of beta blockade and chemical sympathectomy on myocardial function and arrhythmias in acute ischaemia. Cardiovasc Res 1973; 7:740-7. [PMID: 4785547 DOI: 10.1093/cvr/7.6.740] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
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16
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The vascular pattern of the myocardium of the right ventricle and interventricular septum of normal hearts from East Africans in Uganda. THE AFRICAN JOURNAL OF MEDICAL SCIENCES 1973; 4:435-45. [PMID: 4600211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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17
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18
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Relationship between organ weight and blood flow in rats adapted to simulated high altitude. AEROSPACE MEDICINE 1973; 44:1036-9. [PMID: 4744248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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19
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20
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Abstract
A new method to determine myocardial blood distribution was used to study a patient with a recent large transmural anterior myocardial infarct. The method consisted of injecting
43
potassium into a peripheral arm vein and recording the radioactivity over the chest with a scintillation (Anger) camera. Elimination of noncardiac radioactivity in the analysis of data was accomplished by recording the rapid passage of injected
99m
technetium through the heart. The cardiac deposition of the potassium was visualized by identifying the contour of the heart from the technetium scan. In this patient deposition of
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potassium was markedly reduced in the septal region of the myocardium. This correlated well with the ischemic area suggested by coronary angiography, which demonstrated proximal occlusion of the left anterior descending coronary artery and absence of obstructive disease in the other coronary arteries. Intracoronary artery injection of
43
K gave confirmation of decreased deposition in the same area. This method should prove helpful in the study of certain clinical problems, such as the evaluation of the patency of coronary artery bypass grafts.
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Postnatal development of coronary arteries in the rat. ZEITSCHRIFT FUR ANATOMIE UND ENTWICKLUNGSGESCHICHTE 1973; 141:89-101. [PMID: 4746512 DOI: 10.1007/bf00523367] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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22
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Cineangiographic estimation of the left ventricular volume during acute myocardial ischaemia in dogs. ACTA RADIOLOGICA: DIAGNOSIS 1973; 14:43-55. [PMID: 4578838 DOI: 10.1177/028418517301400107] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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23
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Factors determining the distribution and adequacy of left ventricular myocardial blood flow. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1973; 39:95-113. [PMID: 4766905 DOI: 10.1007/978-1-4615-9020-0_7] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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24
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Effect of pentaerythritol-tetranitrate on blood flow through the ischemic and non-ischemic myocardium. JAPANESE HEART JOURNAL 1972; 13:502-11. [PMID: 4539939 DOI: 10.1536/ihj.13.502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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25
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Abstract
Evidence is presented supporting the hypothesis that the positive inotropic effect after an abrupt increase in systolic pressure (Anrep effect) is the recovery from subendocardial ischemia induced by the increase and subsequently corrected by vascular autoregulation of the coronary bed. Major evidence consists of data obtained from an isolated heart preparation showing that the Anrep effect can be abolished with coronary vasodilation, and that with an abrupt increase in systolic pressure there is a significant reduction in the distribution of coronary flow to subendocardial layers of the ventricle. Furthermore, the intracardiac electrocardiogram shows S-T segment and T wave changes after an abrupt increase in ventricular pressure similar to that noted after coronary constriction. Major implications are that normally there may be ischemia of the subendocardial layers tending to reduce myocardial contractility which may account, in part, for the positive inotropic effect of various coronary vasodilators; that with an abrupt increase in ventricular pressure the subendocardium is rendered temporarily ischemic, placing the heart in jeopardy from arrhythmias until this is corrected; and that end-diastolic pressure and the intracardiac electrocardiogram may provide a means of evaluating the adequacy of circulation to subendocardial layers in diseased ventricles when systolic pressure is abruptly increased.
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[Coronary circulation. 3. Blood flow of the various parts of the myocardium. (1)]. MASUI. THE JAPANESE JOURNAL OF ANESTHESIOLOGY 1972; 21:1160-7. [PMID: 4566339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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28
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Angiographic demonstration of important anatomic variations of the posterior descending coronary artery. THE AMERICAN JOURNAL OF ROENTGENOLOGY, RADIUM THERAPY, AND NUCLEAR MEDICINE 1972; 116:41-9. [PMID: 5055646 DOI: 10.2214/ajr.116.1.41] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Effects of intraaortic ballon counterpulsation (IABCP) on the distribution of coronary blood flow in experimental ischemic left ventricular failure. THE JOURNAL OF CARDIOVASCULAR SURGERY 1972; 13:305-12. [PMID: 5046064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Effects of intraaortic balloon counterpulsation on the severity of myocardial ischemic injury following acute coronary occlusion. Counterpulsation and myocardial injury. Circulation 1972; 45:1150-9. [PMID: 5032815 DOI: 10.1161/01.cir.45.6.1150] [Citation(s) in RCA: 139] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The effects of intraaortic balloon counterpulsation (IABC) on the magnitude and severity of myocardial ischemic injury were studied in 19 dogs following acute coronary occlusion and in two patients with cardiogenic shock. In the experimental group, epicardial electrocardiograms were taken from 10-14 sites on the anterior surface of the left ventricle following occlusion of the left anterior descending coronary artery or its apical branch. The average S-T-segment elevation ([see Equation in PDF File]) was used as an index of the magnitude of myocardial ischemic injury. In six dogs, two successive 20-min occlusions were performed, and IABC was started prior to the second occlusion. [see Equation in PDF File] 15 min following occlusion decreased from 3.3 ± 0.9 mv after the control occlusion to 1.4 ± 0.4 mv (
P
< 0.01) after the occlusion with IABC. In three dogs in which the occlusion was maintained and IABC initiated 30 min later, [see Equation in PDF File] decreased from 1.2 to 0.6 mv. In six dogs in which IABC was started 3 hours after occlusion, it induced a reduction of [see Equation in PDF File] from 4.2 ± 1.1 to 2.8 ± 1.0 mv (
P
< 0.01). In four dogs, ischemic injury was augmented by isoproterenol infusion (0.25 µg/kg/min), and while continuing the infusion IABC was initiated. It reduced [see Equation in PDF File] from 8.0 ± 1.9 to 5.7 ± 1.8 mv (
P
< 0.05). Thus, IABC reduced the magnitude and extent of myocardial ischemic injury after experimental coronary occlusion, both when IABC was employed prior to, and 3 hours following, coronary occlusion. IABC was also effective in reducing myocardial ischemic injury which had been increased by isoproterenol infusion. Employing a noninvasive technic, which utilizes 35 electrodes on the thorax, the effects of IABC were examined in two patients with cardiogenic shock associated with acute myocardial infarction. Preliminary observations in these patients confirmed the experimental results indicating that IABC reduced myocardial ischemic injury.
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The blood supply of the heart in different monkey species. On the types of myocardial blood supply. Folia Primatol (Basel) 1971; 16:231-47. [PMID: 5004212 DOI: 10.1159/000155405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Blood supply of the posterior wall of the left ventricle in monkeys most often originates from the left coronary artery, having however more variants than in man. Seven types of blood supply of the posterior wall of the left ventricle were determined. Interspecific differences in the frequency of certain types of cardiac blood supply in monkeys were also established. Data on the type of blood supply of the auricle and septum are given.
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[Grandjean's microcatheterization for right heart sounding]. MEDIZINISCHE KLINIK 1971; 66:1558-64. [PMID: 4109593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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34
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[Utilization of the oxygenated blood in the left ventricle by the heart muscle--on surgical therapy of ischemic heart disease]. KYOBU GEKA. THE JAPANESE JOURNAL OF THORACIC SURGERY 1971; 24:803-8. [PMID: 5169398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Intercoronary anastomoses and the right ventricle in dogs. Indian Heart J 1971; 23:288-91. [PMID: 5146623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
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Experimental revascularisation of the myocardium. THE JOURNAL OF CARDIOVASCULAR SURGERY 1971; 12:251-3. [PMID: 5091654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Continuous determination of platelet aggregation during acute hemorrhage in the arterial and venous system of dogs. Pflugers Arch 1971; 328:185-92. [PMID: 5106875 DOI: 10.1007/bf00587729] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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38
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Postmortem angiographic studies on the intercoronary arterial anastomoses. II. Intercoronary arterial anastomoses in occlusive coronary artery disease. JAPANESE CIRCULATION JOURNAL 1970; 34:1221-30. [PMID: 5537986 DOI: 10.1253/jcj.34.1221] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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39
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Postmortem angiographic studies on the intercoronary arterial anastomoses. I. Studies on intercoronary arterial anastomoses in adult human hearts and the influence on the anastomoses of strictures of the coronary arteries. JAPANESE CIRCULATION JOURNAL 1970; 34:1213-20. [PMID: 5537985 DOI: 10.1253/jcj.34.1213] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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40
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[Regulation problems in circulation relieving pumps]. THORAXCHIRURGIE, VASKULARE CHIRURGIE 1970; 18:370-6. [PMID: 5275529 DOI: 10.1055/s-0028-1099234] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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41
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[Effect of intra-aortic balloon pulsation on the hemodynamics and coronary circulation of the competent left ventricle]. THORAXCHIRURGIE, VASKULARE CHIRURGIE 1970; 18:361-9. [PMID: 5275528 DOI: 10.1055/s-0028-1099233] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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42
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Increased vascularity of brain, heart, and skeletal muscle of polycythemic rats. THE AMERICAN JOURNAL OF PHYSIOLOGY 1970; 219:702-4. [PMID: 5450874 DOI: 10.1152/ajplegacy.1970.219.3.702] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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44
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Increased blood supply of the heart muscle after sustained action-nitroglycerin. ARZNEIMITTEL-FORSCHUNG 1970; 20:808-11. [PMID: 4989741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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45
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The continuity of right and left ventricular myocardial sinusoidal spaces and its relation to right ventricular implants. CANADIAN MEDICAL ASSOCIATION JOURNAL 1970; 102:823-8. [PMID: 5445044 PMCID: PMC1946669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Evidence is presented which indicates that blood leaving side branches of an internal mammary artery implanted into the anterior wall of the right ventricle flows from the tunnel in which it lies through myocardial sinusoidal spaces of the anterior right ventricular wall across the midline to fill corresponding spaces in the anterior wall of the left ventricle and thence is carried to the left coronary sinus. The myocardial sinusoidal spaces of right and left ventricles have been well outlined, using injections of polyvinyl acetate and the technique of digestion casts. We have been able to show that there is no barrier between the myocardial sinusoids of the right circulation and those related to the anterior descending branch of the left coronary artery. In structure, these myocardial sinusoidal spaces are quite different from the intramyocardial coronary arteriolar zones which, in 93% of human hearts, are separated from one another without collateral communication.The continuity of the right and left ventricular myocardial sinusoids explains why implantation of a right internal mammary artery into the anterior wall of the right ventricle combined with a corresponding left implant, epicardiectomy and free omental graft, has been so effective in our hands in the treatment of far-advanced human coronary artery insufficiency.
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Abstract
Total and regional coronary blood flow were measured in dogs by left atrial injection of carbonized microspheres labeled with different radioactive isotopes (mean diameter 14 to 61µ). Simultaneously blood was collected at 20 ml/min from a catheter tied into a peripheral artery. The ratios of flow to radioactivity in myocardium and arterial blood should be equal if microspheres are well mixed in the aortic root and are distributed regionally in proportion to flow. This was proved in seven right heart by-pass experiments where coronary venous drainage was measured directly. Also, less than 0.1% of total myocardial radioactivity appeared in coronary venous blood, even with hypoxemia and small microspheres.
Total coronary flow in seven conscious dogs averaged 95 to 150 ml/min/100 g heart; and flow to the left ventricle was 111 to 169 ml/100 g. Although not validated independently, there was evidence that values for flow to each ventricle, the atria and the septum were correct.
The radioactivity per gram of left ventricular subendocardial muscle was 2.5 times that of subepicardial muscle using microspheres 51 to 61µ in diameter, but the ratios were 1.4 and 1.3 using microspheres of mean diameters 20 to 23µ and 14µ, respectively. It is unlikely that any of these microspheres measure blood flow to small portions of the ventricle.
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50
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[Sclerosis of papillary muscles and of the left ventricular heart wall compared in normal and hypertensive patients]. ARCHIVIO "DE VECCHI" PER L'ANATOMIA PATOLOGICA E LA MEDICINA CLINICA 1968; 53:229-39. [PMID: 5740347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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