FRINK Linked Data Fragments server

Matches in SemOpenAlex for { <https://semopenalex.org/work/W1992984188> ?p ?o ?g. }

• W1992984188 endingPage "556" @default.
• W1992984188 startingPage "555" @default.
• W1992984188 abstract "In a setting where ischemic heart disease is the number one cause of death nationally, the subendocardium of the left ventricle is the weakest link in the chain of survival. Fully 60 percent of myocardial infarctions are subendocardial in nature,1Edwards JE: Personal communicationGoogle Scholar with the vast preponderance of these unassociated with recent coronary arterial occlusion.2Miller RD Burchell HD Edwards JE Myocardial infarchon with and without acute coronary occlusion.AMA Arch Int Med. 1951; 88: 597Crossref PubMed Scopus (68) Google Scholar Granted, almost all of these victims exhibited varying degrees of coronary atherosclerosis, but the fact that subendocardial infarction need not be preceded by occlusive phenomena is further documented by its occurrence in carbon monoxide toxicity,3Ehrich WE Bellet S Lewey FH Cardiac changes from carbon monoxide poisoning.Amer J Med Sci. 1944; 208: 511Crossref Google Scholar sickle cell trait,4Fleischer RA Primary cardiomyapathy in nonanemic patients. Association with sickle ell halt.Amer J Cardiol. 1968; 22: 532Abstract Full Text PDF PubMed Scopus (15) Google Scholar norepinephrine infusion,5Szakacs JE Mehlman B Pathologic chages induced by l-norepinephrine: quantitative aspects.Amer J Cardiol. 1960; 5: 619Abstract Full Text PDF PubMed Scopus (108) Google Scholar and profound hypotension, all in the presence of predominantly patent coronary arteries. The description in 1966 of a group of pre-menopausal women with normal coronary arteriograms and objective evidence of myocardial ischemia and necrosis,6Eliot RS Mizukami H Oxygen affinity in persons with acute myocardial infarction and m smokers.Circulation. 1966; 34: 331Crossref Google Scholar usually subendocardial, has been followed by reports of similar patients of both sexes by other investigators.7Likoff W Segal BS Kasparian H Paradox of normal selective coronary arteriograms in patients considered to have unmistakable coronary heart disease.New Eng J Med. 1967; 276: 1063Crossref PubMed Scopus (290) Google Scholar, 8Kemp HG Elliot WC Gorlin R The angtnal syndrome with normal coronary arteriograph.Tr Asroc Amer Physicians. 1967; 80: 59PubMed Google Scholar, 9Neill WA Kassebaum DG Judkins MP Myocardial hypoxia as the basis for angina pectoris in a patient with normal coronary arteriograms.New Eng J Med. 1968; 279: 789Crossref PubMed Scopus (48) Google Scholar, 10Campeau L Myocardial infarction without obstructive disease at coronary arteriography.Canad Med Assoc J. 1968; 99: 837PubMed Google Scholar, 11Eliot RS Bratt G The paradox of myocardial ischemia and necrosis in young women with normal coronary arteriograms.Amer J Cardiol. 1969; 22: 633Abstract Full Text PDF Scopus (114) Google Scholar, 12Dwyer Jr, EM Weiner L Cox JW Angina pectoris in patients with normal and abnormal coronary arteriograms.Hemodynamic and clinical aspects. Amer J Cardiol. 1969; 23: 639Abstract Full Text PDF PubMed Scopus (69) Google Scholar The above observations point to an inescapable conclusion: the subendocardium of the left ventricle is inordinately predisposed to ischemic insult and necrosis. A closer look at the architecture and demands peculiar to this region support this conclusion. Anatomically, the blood supply to the deep myocardial layers appears to be more than adequate, as a distinct and extensive anastomotic arterial plexus has been well demonstrated in this area.13Fulton WFM Arterial anastomoses in the coronary circulation.Scot Med J. 1963; 8: 420Crossref PubMed Scopus (62) Google Scholar, 14Estes EH Entman ML Dixon HB II et al.The vascular supply of the left ventricular wall.Amer Heart J. 1966; 71: 58Abstract Full Text PDF PubMed Scopus (103) Google Scholar, 15Farrer-Brown G Normal and diseased vascular pattern of myocardium of human heart: I. Normal pattern in the left ventricular free wall.Brit Heart J. 1968; 30: 527Crossref PubMed Scopus (26) Google Scholar Radioisotopic studies16Myers WW Honig CR Number and distribution of myocardial capillaries as determinants of myocardial oxygen tension.Amer J Physiol. 1964; 207: 653PubMed Google Scholar imply an increased capillary density and decreased intercapillary distance in the subendocardium. Indeed, the work of some investigators has suggested an augmentation of blood flow to the deeper regions,17Becker L Fortuin NJ Pitt B Regional myocardial blood flow in the conscious dog.Circulation. 1969; 41: 39-40Google Scholar but this has been a tenuous augmentation, becoming less apparent under the conditions of large coronary artery constriction and ischemia. In fact, this region is most poorly perfused at a time when its needs are greatest, as during systole. Peak tissue pressures in the inner half of the left ventricular wall have been shown to exceed coronary perfusion pressures for one-third of the cardiac cycle.18Kirk ES Honig CR An experimental and theoretical analysis of myocardial tissue pressure.Amer J Physiol. 1964; 207: 361PubMed Google Scholar This increase in the extravascular component of coronary resistance is sufficient to cause cessation of blood flow through this area. Radioisotope clearance19Honig CR Kirk ES Myers WW Transmural distributions of blood flow, oxygen tension, and metabolism in myocardium: mechanism and adaptations.in: Int Symp on the Coronary Circulation and Energetics of the Myocardium (Milan 1966.). Karger, Basel/New York1967Crossref Google Scholar and dye20Hirshorn S The effect of changes in transmural pressure on the distribution of coronary flow to the left ventricular myocardium.Amer J Cardiol. 1969; 23: 308Abstract Full Text PDF Google Scholar studies have supported this regional reduction in flow, as has the demonstration of redistribution of flow to the deeper myocardial layers following induced asystole,21Kirk ES Honig CF Nonuniform distribution of blood flow and gradients of oxygen tension within the heart.Amer J Physiol. 1964; 207: 661PubMed Google Scholar when tissue pressures are equalized throughout the myocardium. Yet, the muscle fibers of the subendocardium are the longest in the ventricular wall.22Spotnitz HM Sonnenblick EH Spiro D Relation of ultrastructure to function in the intact heart: sarcomere structure relative to pressure volume curves of intact left ventricles of dog and cat.Circ Res. 1966; 38: 49Crossref Scopus (160) Google Scholar From the geometry and mechanics of ventricular contraction, they perform the greatest work in the development of tension,18Kirk ES Honig CR An experimental and theoretical analysis of myocardial tissue pressure.Amer J Physiol. 1964; 207: 361PubMed Google Scholar and can be expected to consume correspondingly increased amounts of oxygen. It is not surprising, then, that the lowest partial pressures of oxygen in the myocardium are in this area,21Kirk ES Honig CF Nonuniform distribution of blood flow and gradients of oxygen tension within the heart.Amer J Physiol. 1964; 207: 661PubMed Google Scholar along with increased amounts of lactate. AMP, ADP,23Leunissen RLA Piatrek-Leunissen DA Nakamura Y et al.Regional metabolism of the heart during reduced coronary flow.Circulation. 1966; 155: 33-34Google Scholar glycogen, and phosphorylase,24Jedeikin LA Glycogen and phosphorylase distribution throughout the walls of the rabbit heart.Fed Proc. 1961; 20: 302Google Scholar implying a metabolic response and adaptation to hypoxia. The role of myoglobin in myocardial oxygenation remains speculative, and the existence of regional variation in myocardial myoglobin content controversial.19Honig CR Kirk ES Myers WW Transmural distributions of blood flow, oxygen tension, and metabolism in myocardium: mechanism and adaptations.in: Int Symp on the Coronary Circulation and Energetics of the Myocardium (Milan 1966.). Karger, Basel/New York1967Crossref Google Scholar, 25Rakusan K Radl J Poupa O The distribution and content of myoglobin in the heart of the rat during postnatal development.Physiol Bohemoslov. 1965; 14: 317PubMed Google Scholar, 26Anderson NM Brandi G Regional myoglobin concentration in the myocardium of the dog.Canad J Physiol Pharmacol. 1968; 46: 908Crossref PubMed Scopus (0) Google Scholar The subendocardium is richly endowed with Purkinje fibers, which, despite their relatively large size, are supplied by a capillary bed only 40 percent as dense as the surrounding muscle fibers.27Wearn JT The extent of the capillary bed of the heart.J Exp Med. 1928; 47: 273Crossref PubMed Scopus (64) Google Scholar This is in keeping with the lower oxygen requirements of the conducting tissues of the heart. However, the predisposition of the Purkinje-rich subendocardium to ischemia suggests a mechanism for the explanation of ventricular arrhythmias and sudden death unattended by overt myocardial infarction. It is no challenge to the imagination to speculate on the real and potential threats to the tenuous balance of subendocardial oxygenation, either singly or in concert. In our society the ubiquitous process of atherosclerosis provides the ominous base upon which a multitude of stresses may be grafted. Hypoxia, hypotension, tachycardia, inotropic agents, anemia, abnormal oxygen transport, and other deleterious factors may well interact in the face of a still patent coronary vasculature to produce subendocardial ischemia and necrosis. Per milliliter of blood flow, the heart is man's most oxygen-hungry organ; how ironic it is that its most needy area is its least nourished." @default.
• W1992984188 created "2016-06-24" @default.
• W1992984188 creator A5063458266 @default.
• W1992984188 creator A5091104630 @default.
• W1992984188 date "1970-12-01" @default.
• W1992984188 modified "2023-09-26" @default.
• W1992984188 title "The Subendocardium of the Left Ventricle, A Physiologic Enigma" @default.
• W1992984188 cites W1591137397 @default.
• W1992984188 cites W1595694382 @default.
• W1992984188 cites W1601996212 @default.
• W1992984188 cites W1974818827 @default.
• W1992984188 cites W2027716525 @default.
• W1992984188 cites W2030322059 @default.
• W1992984188 cites W2034288210 @default.
• W1992984188 cites W2047956773 @default.
• W1992984188 cites W2054458370 @default.
• W1992984188 cites W2061444712 @default.
• W1992984188 cites W2093227971 @default.
• W1992984188 cites W2336279028 @default.
• W1992984188 cites W2341028909 @default.
• W1992984188 cites W2397647993 @default.
• W1992984188 cites W2401481029 @default.
• W1992984188 cites W2410739540 @default.
• W1992984188 cites W2413685787 @default.
• W1992984188 cites W4247964405 @default.
• W1992984188 doi "https://doi.org/10.1378/chest.58.6.555" @default.
• W1992984188 hasPubMedId "https://pubmed.ncbi.nlm.nih.gov/5486545" @default.
• W1992984188 hasPublicationYear "1970" @default.
• W1992984188 type Work @default.
• W1992984188 sameAs 1992984188 @default.
• W1992984188 citedByCount "26" @default.
• W1992984188 countsByYear W19929841882022 @default.
• W1992984188 crossrefType "journal-article" @default.
• W1992984188 hasAuthorship W1992984188A5063458266 @default.
• W1992984188 hasAuthorship W1992984188A5091104630 @default.
• W1992984188 hasBestOaLocation W19929841881 @default.
• W1992984188 hasConcept C126322002 @default.
• W1992984188 hasConcept C164705383 @default.
• W1992984188 hasConcept C2778921608 @default.
• W1992984188 hasConcept C71924100 @default.
• W1992984188 hasConcept C85378888 @default.
• W1992984188 hasConceptScore W1992984188C126322002 @default.
• W1992984188 hasConceptScore W1992984188C164705383 @default.
• W1992984188 hasConceptScore W1992984188C2778921608 @default.
• W1992984188 hasConceptScore W1992984188C71924100 @default.
• W1992984188 hasConceptScore W1992984188C85378888 @default.
• W1992984188 hasIssue "6" @default.
• W1992984188 hasLocation W19929841881 @default.
• W1992984188 hasLocation W19929841882 @default.
• W1992984188 hasOpenAccess W1992984188 @default.
• W1992984188 hasPrimaryLocation W19929841881 @default.
• W1992984188 hasRelatedWork W2032356666 @default.
• W1992984188 hasRelatedWork W2040291984 @default.
• W1992984188 hasRelatedWork W2075010150 @default.
• W1992984188 hasRelatedWork W2078545226 @default.
• W1992984188 hasRelatedWork W2103683515 @default.
• W1992984188 hasRelatedWork W2387494991 @default.
• W1992984188 hasRelatedWork W2412762768 @default.
• W1992984188 hasRelatedWork W2416155686 @default.
• W1992984188 hasRelatedWork W2606815792 @default.
• W1992984188 hasRelatedWork W3018544310 @default.
• W1992984188 hasVolume "58" @default.
• W1992984188 isParatext "false" @default.
• W1992984188 isRetracted "false" @default.
• W1992984188 magId "1992984188" @default.
• W1992984188 workType "article" @default.