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The Coronary Circulation in Patients with Severe Emphysema, Cor Pulmonale, Cyanotic Congenital Heart Disease, and Severe Anemia
The Coronary Circulation in Patients with Severe Emphysema, Cor Pulmonale, Cyanotic Congenital Heart Disease, and Severe Anemia * HENRY A. ZIMMERMAN, M.D. Cleveland, Ohio In a recent publication we have described a method of injection of the coronary artertes.! That work, a study of coronary artery patterns and their normal variations, utilized a modification of the Schlesinger injection technique. The injection mass used was a barium latex compound in which the particle size of the injection material had been standardized by screening viscosity determinations and ocular micrometer examination at 14 micra. The present study has to do with a particular phase of coronary artery circulation as demonstrated by the injection technique; namely the development of collateral or anastomotic circulation in patients with severe emphysema, cor pulmonale, cyanotic congenital heart disease, and severe anemia. From the pathological physiology it can be seen that these four disease states have one thing in common and that is anoxia. In severe emphysema the oxygen saturation of the arterial blood may and does run, as low as 70 per cent. In our laboratory, studies of the arterial 02 saturation in severe anemias, have been in the normal range, however, the 02 carrying capacity may be reduced to below a third normal which results in a local 02 want at the cell level, since only one-third of the normal amount of 02 is being delivered into the cells. In cyanosis with polycythemia there is enough circulatory hemoglobin but once more , it is not carrying its full quota of 02 so again there is a deficit in oxygen at the cell level. Although it has been taught since the days of Conheim, that the coronary arteries were end arteries, it has gradually become accepted that an anastomotic circulation exists within the normal heart. That such an anastomotic circulation normally connects the capillaries and other finer vessels is indeed well established, and Gross, Spalteholz and Campbell, as a result of their studies,
-From the Cardio-pulmonary Laboratory, st. Vincent's Charity Hospital, Cleveland,Ohio. A portion of this work was done while the author was Director of the Cardiovascular Research Laboratory, City Hospital, Cleveland, Ohio. The author Is indebted to A. F. Young, M.D., who aided in the routine injections during this period. 269
270
HENRY A. ZIMMERMAN
Bept., 1852
believed that with increasing age, an anastomotic circulation was also developed within pre-capillary vessels .2 •3 In 1940 Blumgart and his associates reported an investigative work which was not entirely in accord with this view.1I They were unable to demonstrate any evidence of an anastomotic connection between the right and left coronary arteries in the hearts of patients in the seventh and eighth decades of life who had shown no evidence of cardiovascular disease and had only minimal coronary artery sclerosis. The injection material used for this study rarely penetrated the vessels of smaller caliber than 40 micra, however, and it is well known, that watery solutions injected into the right coronary arteries are regularly recovered in the branches of the left coronary artery and vice versa in normal hearts. It can be concluded, therefore, that the diameter of the connecting vessels is less than 40 micra. It seemed to us that the barium latex injection mass with a standardized particle size of 14 micra was ideally suited to the investigation of this problem, because while readily penetrating to vessels of pre-capillary diameter, the capillary beds themselves were not fUled or visualized. It has been shown by Blumgart and his associates that anastomotic circulation invariably exists in relation to considerable narrowing or old com-
FIGURE 1: Shows a normal coronary injection with a right sided predominance.
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plete occlusions of the coronary arteries and that anastomotic circulation is also found in the presence of rheumatic valvular disease or arterial hypertension with little or no coronary artery narrowing or occlusion. We have, therefore, largely confined the present investigation to a study of the coronary circulation in patients with cor pulmonale, cyanotic congenital heart disease, and severe anemia. In the review of material from our first 165 cases, we have found 13 cases with a very significant increase in the small ramifications of the coronary arteries, which were visualized by x-ray examination after injection of the barium latex mixture by the previously described technique. Of these 13 cases, six are of cor pulmonale, three are of chronic severe pulmonary emphysema, one is of aplastic anemia, two are of untreated pernicious anemia and one is of congenital heart disease with cyanosis and polycythemia. Figure 1 reveals the coronary circulation in a normal heart which has been prepared by the injection technique. Figure 2 shows the heart of a patient with cyanosis and polycythemia. A comparison of these two figures readily demonstrates a marked increase in the number of small coronary branches visualized in the right and left ventricles of the injected specimen, so much so in the right ventricle as to approach in
FIGURE 2: The coronary circulation in a heart from a case of congenital cyanotic heart disease, note marked increase in development of anastomotic vessels.
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HENRY A. ZIMMERMAN
Sept., 1952
number the ramifications of the left ventricle. These findings were consistently shown in all of the 13 cases mentioned above. The myriad ramifications of the coronary tree are readily seen even in the reproductions. The experimental studies to date do not afford an explanation of the various factors involved in the development of this anastomotic circulation. The only reference to collateral coronary circulation in anemia which we have found in that of Amadeo" who hypothecated on purely clinical grounds that anemia may effect a beneficial effect on the heart by compelling it to develop a special compensatory mechanism to offset the attendant myocardial anoxia. He further hypothecated that this mechanism might well be the reduced blood viscosity of anemia which could open up existing but nonfunctioning coronary artery connections. This theory would not explain the increase in number of anastomotic channels found in cases of cor pulmonale, many of which have polycythemia and increased blood viscosity. Patients with cor pulmonale do show anoxemia and a low oxygen saturation of arterial blood may be the initiating factor in the development of the collateral circulation. We submit, therefore, that it is the increased local cardiac need or perhaps myocardial anoxia which is the primary factor in the development of such circulation, regardless of whether that need is occasioned by increased work of a part of the myocardium, coronary artery insufficiency, or decrease in the amount of circulating oxygenized hemoglobin from any cause whatsoever. SUMMARY
This paper deals with the coronary circulation in patients with severe emphysema, cor pulmonale, cyanotic congenital heart disease and severe anemia. RESUMEN
Este trabajo se refiere a la circulaci6n coronaria en los enfermos con enfisema severo, cor pulmonale, enfermedad congenita cianotica cardiaca y anemia severa. RESUME
Cette communication a trait a. la circulation coronarienne chez les malades atteints d'emphyseme severe, de coeur pulmonaire, de cyanose congenltale et d'anemie grave. REFERENCES 1 Scott, R. W., Young, A. F., Zimmerman, H. A. and Kroh, Ileen, B. S.: "An Improved Method for VIsualiz1ng the Coronary Arteries at Post Mortem," Am. Heart Journal, 38:881, 1949.
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2 Gross, L.: "The Blood Supply to the Heart in the Anatomical and Clinical Aspects," New York, 1921. Paul B. Hoeber. 3 Spalteholz, W.: "Die Arterien Der Herzward," Leipzig, 1924. S. Hirzel. 4 Campbell, J. S.: "stereoscopic Radiography of the Coronary System," Quart. J. Meet., 22:247, 1929. 5 Blumgart, H. L., Schlesinger, M. D~ and Davis, David: "Studies on the Relation of the Clinical Manifestations of Angina Pectoris, Coronary Thrombosis and Myocardial Infarction to the Pathologic Findings," Am . Heart Journal, 19:1, 1940. 6 Amadeo, J. A.: "The Suggestion for Improving Structure of the Cardiac Coronary Circulation System Without Surgical Intervention," Am. Heart Journal, 28:699, 1944.
-From the Cardio-pulmonary Laboratory, st. Vincent's Charity Hospital, Cleveland,Ohio. A portion of this work was done while the author was Director of the Cardiovascular Research Laboratory, City Hospital, Cleveland, Ohio. The author Is indebted to A. F. Young, M.D., who aided in the routine injections during this period. 269
270
HENRY A. ZIMMERMAN
Bept., 1852
believed that with increasing age, an anastomotic circulation was also developed within pre-capillary vessels .2 •3 In 1940 Blumgart and his associates reported an investigative work which was not entirely in accord with this view.1I They were unable to demonstrate any evidence of an anastomotic connection between the right and left coronary arteries in the hearts of patients in the seventh and eighth decades of life who had shown no evidence of cardiovascular disease and had only minimal coronary artery sclerosis. The injection material used for this study rarely penetrated the vessels of smaller caliber than 40 micra, however, and it is well known, that watery solutions injected into the right coronary arteries are regularly recovered in the branches of the left coronary artery and vice versa in normal hearts. It can be concluded, therefore, that the diameter of the connecting vessels is less than 40 micra. It seemed to us that the barium latex injection mass with a standardized particle size of 14 micra was ideally suited to the investigation of this problem, because while readily penetrating to vessels of pre-capillary diameter, the capillary beds themselves were not fUled or visualized. It has been shown by Blumgart and his associates that anastomotic circulation invariably exists in relation to considerable narrowing or old com-
FIGURE 1: Shows a normal coronary injection with a right sided predominance.
Vol.
xxn
CORONARY CIRCULATION
271
plete occlusions of the coronary arteries and that anastomotic circulation is also found in the presence of rheumatic valvular disease or arterial hypertension with little or no coronary artery narrowing or occlusion. We have, therefore, largely confined the present investigation to a study of the coronary circulation in patients with cor pulmonale, cyanotic congenital heart disease, and severe anemia. In the review of material from our first 165 cases, we have found 13 cases with a very significant increase in the small ramifications of the coronary arteries, which were visualized by x-ray examination after injection of the barium latex mixture by the previously described technique. Of these 13 cases, six are of cor pulmonale, three are of chronic severe pulmonary emphysema, one is of aplastic anemia, two are of untreated pernicious anemia and one is of congenital heart disease with cyanosis and polycythemia. Figure 1 reveals the coronary circulation in a normal heart which has been prepared by the injection technique. Figure 2 shows the heart of a patient with cyanosis and polycythemia. A comparison of these two figures readily demonstrates a marked increase in the number of small coronary branches visualized in the right and left ventricles of the injected specimen, so much so in the right ventricle as to approach in
FIGURE 2: The coronary circulation in a heart from a case of congenital cyanotic heart disease, note marked increase in development of anastomotic vessels.
272
HENRY A. ZIMMERMAN
Sept., 1952
number the ramifications of the left ventricle. These findings were consistently shown in all of the 13 cases mentioned above. The myriad ramifications of the coronary tree are readily seen even in the reproductions. The experimental studies to date do not afford an explanation of the various factors involved in the development of this anastomotic circulation. The only reference to collateral coronary circulation in anemia which we have found in that of Amadeo" who hypothecated on purely clinical grounds that anemia may effect a beneficial effect on the heart by compelling it to develop a special compensatory mechanism to offset the attendant myocardial anoxia. He further hypothecated that this mechanism might well be the reduced blood viscosity of anemia which could open up existing but nonfunctioning coronary artery connections. This theory would not explain the increase in number of anastomotic channels found in cases of cor pulmonale, many of which have polycythemia and increased blood viscosity. Patients with cor pulmonale do show anoxemia and a low oxygen saturation of arterial blood may be the initiating factor in the development of the collateral circulation. We submit, therefore, that it is the increased local cardiac need or perhaps myocardial anoxia which is the primary factor in the development of such circulation, regardless of whether that need is occasioned by increased work of a part of the myocardium, coronary artery insufficiency, or decrease in the amount of circulating oxygenized hemoglobin from any cause whatsoever. SUMMARY
This paper deals with the coronary circulation in patients with severe emphysema, cor pulmonale, cyanotic congenital heart disease and severe anemia. RESUMEN
Este trabajo se refiere a la circulaci6n coronaria en los enfermos con enfisema severo, cor pulmonale, enfermedad congenita cianotica cardiaca y anemia severa. RESUME
Cette communication a trait a. la circulation coronarienne chez les malades atteints d'emphyseme severe, de coeur pulmonaire, de cyanose congenltale et d'anemie grave. REFERENCES 1 Scott, R. W., Young, A. F., Zimmerman, H. A. and Kroh, Ileen, B. S.: "An Improved Method for VIsualiz1ng the Coronary Arteries at Post Mortem," Am. Heart Journal, 38:881, 1949.
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2 Gross, L.: "The Blood Supply to the Heart in the Anatomical and Clinical Aspects," New York, 1921. Paul B. Hoeber. 3 Spalteholz, W.: "Die Arterien Der Herzward," Leipzig, 1924. S. Hirzel. 4 Campbell, J. S.: "stereoscopic Radiography of the Coronary System," Quart. J. Meet., 22:247, 1929. 5 Blumgart, H. L., Schlesinger, M. D~ and Davis, David: "Studies on the Relation of the Clinical Manifestations of Angina Pectoris, Coronary Thrombosis and Myocardial Infarction to the Pathologic Findings," Am . Heart Journal, 19:1, 1940. 6 Amadeo, J. A.: "The Suggestion for Improving Structure of the Cardiac Coronary Circulation System Without Surgical Intervention," Am. Heart Journal, 28:699, 1944.