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SPLEEN GRAFTS UPON THE HEART: EFFECT UPON INTERCORONARY BLOOD FLOW
SPLEEN GRAFTS U P O N THE HEART: EFFECT U P O N INTERCORONARY BLOOD FLOW David S. Leighninger,
M.D., Claude S. Beck,
M.D.,
Raimund Rueger, M.D., and Shoji Eguchi, M.D., Cleveland,
Ohio
T
HE value of intercoronary arterial communications in the presence of coronary artery disease scarcely needs discussion. These vascular channels protect against anginal pain. They also reduce electrical disturbances in the heart when the blood supply through a larger vessel is reduced or obstructed. They also reduce the size of the infarct if and when an artery becomes blocked off subsequent to the production of these channels. The ways and means of producing these communications has been and continues to be an important area for research in our laboratory. Grafts of spleen were placed upon the heart to determine their effect upon intercoronary blood flow. In humans, particles of spleen have seeded themselves in the abdomen and elsewhere when the spleen was ruptured and fragmented and the organ was removed at operation. 1 These particles of spleen developed their own blood supply. This subject of spleen growing elsewhere has been investigated in experimental animals.2"4 According to Manley and Marine, homotransplants in rabbits did not take after 2 or 3 weeks and only one out of six autographs was a long-term take. Garamella and Hay 5 placed fragments of spleen in the pericardium of 7 dogs and after one to 5 weeks reported that the grafts had taken and that vascular channels or bridges were found between coronary arteries in 6 of these specimens. This was a preliminary report and the authors have not made a subsequent report. Seltzer and Maddock6 removed three fourths of the spleen and transplanted the remainder with its blood supply upon the surface of the heart in 30 dogs. The epicardium and the capsule of the spleen were thoroughly abraded so that these structures would not be a barrier to the growth of blood vessels from spleen to heart. Mortality tests were carried out later. These consisted of placing a ligature around a coronary artery. The descending ramus of the left coronary artery was ligated in 30 dogs and the mortality was-0. One month later the right coronary artery was ligated in 12 of these dogs and the mortality again was 0. The circumflex artery was ligated in 4 of the original group and the mortality again was 0. Thus a From the Western Reserve University, Cleveland, Ohio. This work was supported by grants from the TT. S. Public Health Service and the Cleveland Area Heart Society. Received for publication May 21, 1962. 412
Vol. 45. No. 3 March, 1963
S P L E E N GRAFTS U P O N HEART
413
second artery was ligated in 16 of the 30 dogs without mortality. It is obvious that this subject should receive further investigation because it might have practical application to humans with coronary artery disease. METHOD OF STUDY
The baekflow method of study was used. This method was described by Anrep and Ilausler 7 in 1928, by Mautz and Gregg8 in 1937, and also by Leighninger in 1959." The method involves ligation of the circumflex coronary artery at its origin. This artery is cut across distal to the ligature. The blood that escapes from the open end of the artery is the baekflow. It comes from the other patent coronary arteries by way of intercoronary anastomoses. This blood is available to the area of muscle that was made ischemic by the ligature on the artery. It escapes from the cut artery without going through the high-resistant capillary bed. If some of this blood did escape through the capillary bed it would be lost to the measurements. The amount of baekflow varies with aortic pressure. This was kept at a constant level of 100 mm. Hg. The pressure was reduced to this level by bleeding or was brought up to this level by a screw-clamp on the aorta. Three to six determinations for 30 seconds each were made at 5 minute intervals and the average figure became the baekflow. It was expressed in terms of cubic centimeters for one minute. Between determinations, the circumflex artery was perfused from the carotid artery to prevent ischemic changes in the muscle and also to prevent ventricular fibrillation. Average baekflow measurements in various groups of normal dogs showed some variations. Thus Leighninger 10 found the average to be 3.8 c.c. per minute on 67 normal dogs of which Eckstein did 41. One high measurement was 21.0 c.c. per minute. He also found the baekflow after the Beck operation was 8.5 c.c. per minute in 41 dogs.10 One high measurement in this group was 26.0 e.c. per minute. The conclusion was made that operation increased backflow by 4.7 c.c. per minute. In the study on nitroglycerin, the average baekflow in 21 normal dogs was 4.49 c.c. per minute and nitroglycerin increased this by 0.88 c.c. per minute. 9 The variation in the two groups of normal dogs was 0.7 c.c. (4.49 versus 3.8). These measurements on normal dogs are the basis for comparison with those in which spleen grafts were used. Leighninger and Eckstein11 reported average baekflow determinations of 6.9 c.c. per minute in 10 dogs in which a sham Beck 2 operation was done. This procedure consisted in placing a vein graft between aorta and coronary sinus and immediate ligation of the graft so that no blood flowed through the shunt. These authors also reported average baekflow of 4.3 c.c. per minute in 9 dogs whose hearts had been fibrillated by an outside current and then defibrillated by the open-chest method. The conclusion was made that trauma on the surface of the heart, such as that produced by surgical exposure and manipulation, produced an inflammatory reaction which in turn increased baekflow. It is not possible to make serial determinations on the same dog before and after placing spleen grafts on the heart because the manipulation in the artery and on the heart would augment baekflow for the second series of determinations. It is necessary to deal with
L E I G H N I N G E K ET AL.
414
J. Thoracic and Cardiovas. Surg.
average figures for the normal and compare these with average figures after the grafts were placed. EXPERIMENTS
1. Autogenous Splenic Pulp.—The left chest was opened. The diaphragm was incised and the spleen was removed. Part of the spleen was macerated into a pulp. The pericardium was incised for several centimeters and the pericardial cavity was filled with splenic pulp. The pericardium was closed with sutures. Backflow measurements were done 23 to 29 days later. The average backflow in 10 dogs was 7.4 c.c. per minute, with a range of 2.4 to 15.6. None of these grafts were successful " t a k e s . " Viable graft was not found. The reaction between heart and pericardium was mild; only a few adhesions were found between heart and pericardium. 2. Autogenous Slices of Spleen.—The left chest was opened. The diaphragm was opened. The spleen was delivered into the chest. About one fourth of the spleen was removed for grafting. The incised surface of the spleen was closed by sutures and returned to the abdomen. The incision in the diaphragm was closed. This portion of spleen was cut into thin slices and sutures were placed between these slices of spleen and pericardium so that a large area of pericardium was covered by these slices of spleen. The pericardium was then closed and the grafts were in contact with the heart. Positive " t a k e s " in 9: One or more slices of spleen appeared to be viable in 9 experiments. These positive takes were confirmed by microscopic sections. The average backflow in these experiments was 7.4 c.c. per minute, with a range of 2.4 to 16.4. The average period of time after grafting was 96 days, with a range of 66 and 125 days. The surface of the graft bled when the pericardium was separated from the graft. The graft was about one fourth the original size of the transplant. No " t a k e s " in 9: There were 9 experiments in which viable spleen was not found. These specimens were examined on an average of 75 days after they were placed, with a range of 60 to 88. In most of the specimens, adhesions were found between heart and pericardium. With several exceptions these were easily broken with the finger and the surface did not bleed. Dense adhesions were found in three experiments. The average backflow was 7.6 c.c. per minute, with a range of 3.8 to 13.8. 3. Autogenous Spleen Grafts With Intact Vascular Pedicle.—The left diaphragm was opened for about 3 to 4 cm. and the spleen was brought up through this opening. Approximately three fourths of the spleen was removed. The remaining portion of spleen was used as a graft with its blood supply intact. The graft was fashioned so as to get the longest possible pedicle. The opening in the diaphragm was made as small as possible and in some experiments sutures were placed between diaphragm and pedicle. The capsule of the graft which was to come into contact with the heart was abraded. The epieardium was abraded over the area of contact. Time was taken to stop the oozing of blood
Vol. 45, No. 3
March, 1963
S P L E E N GRAFTS U P O N H E A R T
415 *.*."
before the graft was placed. The pericardium was opened and pericardium and graft were sutured so that the abraded surface of the graft was in contact with the heart. The area of contact was about 5 cm. in each direction. Satisfactory backnow determinations were made in 13 experiments. The average determination was 8.3 c.c. per minute, with a range of 1.2 to 46.8. The average backnow without this one high determination was 5.3. The average duration of the experiment was 37 days, with a range of 32 to 41. All grafts were viable. In some of the experiments the spleen was not adherent to the heart. In most of the specimens the contact between graft and heart was slight and adhesions were easily broken. Dense adhesions were present in 3 specimens. The highest and the lowest backflows were in this small group. A mixture of barium sulfate and gelatin was injected into the coronary arteries in 9 specimens. This injection mass was thicker than blood and did not enter arteries less than 40 microns in diameter. These specimens were cleared.12 Injection-mass was found in 4 grafts which indicated the presence of vascular channels between heart and grafts. Intercoronary communications were present in 7 specimens. These were greater than normal and the conclusion is that they were produced by the operation. The mortality in these experiments was the significant figure of 30 per cent. Herniation was the usual cause of death. 4. Homologous Grafts.—The spleen of a dog was removed aseptically and cut into four parts. Each of these pieces was cut into thin slices and placed in normal sodium chloride solution or in Tyrode's solution containing penicillin. Each container was sealed and placed in the refrigerator. This material was used as graft within a period of 10 days. I t was applied as in Group 2 of the experiments. Backflow measurements were made 25 to 69 days later. The average backflow in 31 dogs was 9.0 c.c. per minute, with a range of 1.6 to 39.7. None of the grafts was viable. The grafted tissue disappeared leaving localized adhesions between heart and pericardium at the site of the grafts. In most of the specimens the reaction produced by these grafts was not severe. In several specimens dense adhesions were present. The surfaces did not bleed when separated by the finger. The coronary arteries were injected in 23 specimens. These were cleared. The site of the grafts was examined for injection-mass. Injection-mass was present at the site of the grafts in 2 specimens. It was not found in 21 specimens. The specimens were examined for intercoronary channels. These were estimated to be within the range of normal in 9 specimens. They were greater than normal in 14 specimens. The conclusion was that the presence of the homologous spleen grafts plus the reaction brought about by the operative procedure produced these intercoronary channels. These channels also explained the high backflow measurements. It is significant that this correlation existed between the amount of backflow and the demonstration of channels that transported this blood. The amount of backflow varies directly with the capacity of the intercoronary channels. DISCUSSION
Grafts of spleen placed on the surface of the heart increased backflow measurements over normal values. The average backflow in one series of normal dogs
L E I G H N I N G E R E T AL.
416
J. Thoracic and Cardiovas. Surg.
was 3.8 c.c. per minute; in another series of normal dogs it was 4.49 c.c. per minute. 1 0 ' J 1 Autogenous splenic pulp was placed in the pericardial cavity and backflow determinations were done several weeks later. These were increased by about 3 c.c. per minute to 7.4 c.c. Autogenous splenic pulp did not produce a single viable graft. Autogenous slices of spleen were placed on the heart in 18 experiments. Nine of these were positive takes confirmed by microscopic examination. Backflow was increased by about 3 c.c. per minute to 7.4 c.c. The size of the positive takes was about one fourth of the original graft. They became smaller and the development of new blood vessels was not significant. In 9 experiments, splenic tissue was not found at the site where grafts were placed. Splenic tissue had disappeared. The effect upon backflow was about the same as in the experiments in which splenic tissue was found. Autogenous spleen grafts with intact vascular pedicle were placed in 13 experiments. In these experiments the backflow was 8.3 c.c. which is an increase of 4.5 c.c. over normal average levels. Homologous grafts of spleen were placed in 31 experiments. None of these were positive takes. Backflow determinations were 9.0 c.c. The coronary arteries were injected in 23 of these experiments and the specimens were cleared. In 14 of these specimens, transport channels between coronary arteries were well above the average normal appearance. These channels accounted for the increased backflow. This correlation between anatomy and function is related to the genesis of anginal pain and fibrillating electricity (fatal heart attack) in the human because both of these are due to uneven distribution of blood in the heart muscle. CONCLUSIONS
Transplants of spleen were placed upon the surface of the heart. Backflow determinations in these experiments were 7.4 c.c. in one series of experiments and 9.0 c.c. in another series of experiments. In the presence of coronary artery occlusion these values give some measure of coronary collateral circulation. These backflow values are not higher than those produced by the Beck 1 operation. Spleen grafts have limited power of viability and no power for growth and the development of an independent blood supply, such as was occasionally found in the human when the spleen was fragmented by injury and particles seeded themselves and developed an independent blood supply. REFERENCES 1. Storsteen, K. A., and EeMine, W. H . : Rupture of the Spleen With Splenic Implants: Splenosis. Review of Literature and Report of a Case, Ann. Surg. 137: 551, 1953. 2. Marine, D., and Manley, 0 . T . : Influence of Age on the Permanence of Subcutaneous Autografts of the Spleen in Rabbits, Proc. Soc. Exper. Biol. & Med. 14: 123, 19161917. 3. Manley, O. T., and Marine, D . : The Transplantation of Splenic Tissue Into the Subcutaneous Fascia of the Abdomen in Rabbits, J . Exper. Med. 25: 619, 1917. 4. Perla, D . : The Regeneration of Autoplastic Splenic Transplants, Am. J . Path. 12: 665, 1936.
Vol. 45, No. 3 March, 1963
S P L E E N GRAFTS U P O N H E A E T
417
5. Garamella, J . J . , a n d Hay, L . J . : Autotransplantation of Spleen: Splenosis—Case Report and Preliminary Report of a n Experimental Study in Revascularization of the Heart, Ann. Surg. 140: 107, 1954. 6. Seltzer, E . I., and Maddock, S. J . : Technique for Supplementing Coronary Circulation by Means of a Splenic Graft, Rhode Island M. J . 39: 195, 1956. 7. Anrep, G. V., and Hausler, H . : The Coronary Circulation. I . The Effect of Changes of the Blood Pressure and of the Output of the Heart, J . Physiol. 6 6 : 357, 1928. 8. Mautz, F . R., and Gregg, D. E . : The Dynamics of Collateral Circulation Following Chronic Occlusion of Coronary Arteries, Proe. Soc. Exper. Biol. & Med. 3 6 : 797, 1937. 9. Leighninger, D. S., Rueger, R., and Beck, C. S.: Effect of Glyceryl Trinitrate (Nitroglycerin) on Arterial Blood Supply t o Ischemic Myocardium, Am. J . Cardiol. 3 : 638, 1959. 10. Leighninger, D. S.: A Laboratory and Clinical Evaluation of Operations for Coronary Artery Disease, J . THORACIC SURG. 30: 397, 1955.
11. Leighninger, D. S., and Eckstein, R. W . : Further Observations on Aorta to Coronary Sinus Anastomosis of Beck in Dogs, Proc. Soc. Exper. Biol. & Med. 87: 564, 1954. 12. Wolfe, K . : Plastic Embedded Hearts—Cleared and Corroded Specimens, A. M. A. Arch. Path. 6 1 : 153, 1956.
M.D., Claude S. Beck,
M.D.,
Raimund Rueger, M.D., and Shoji Eguchi, M.D., Cleveland,
Ohio
T
HE value of intercoronary arterial communications in the presence of coronary artery disease scarcely needs discussion. These vascular channels protect against anginal pain. They also reduce electrical disturbances in the heart when the blood supply through a larger vessel is reduced or obstructed. They also reduce the size of the infarct if and when an artery becomes blocked off subsequent to the production of these channels. The ways and means of producing these communications has been and continues to be an important area for research in our laboratory. Grafts of spleen were placed upon the heart to determine their effect upon intercoronary blood flow. In humans, particles of spleen have seeded themselves in the abdomen and elsewhere when the spleen was ruptured and fragmented and the organ was removed at operation. 1 These particles of spleen developed their own blood supply. This subject of spleen growing elsewhere has been investigated in experimental animals.2"4 According to Manley and Marine, homotransplants in rabbits did not take after 2 or 3 weeks and only one out of six autographs was a long-term take. Garamella and Hay 5 placed fragments of spleen in the pericardium of 7 dogs and after one to 5 weeks reported that the grafts had taken and that vascular channels or bridges were found between coronary arteries in 6 of these specimens. This was a preliminary report and the authors have not made a subsequent report. Seltzer and Maddock6 removed three fourths of the spleen and transplanted the remainder with its blood supply upon the surface of the heart in 30 dogs. The epicardium and the capsule of the spleen were thoroughly abraded so that these structures would not be a barrier to the growth of blood vessels from spleen to heart. Mortality tests were carried out later. These consisted of placing a ligature around a coronary artery. The descending ramus of the left coronary artery was ligated in 30 dogs and the mortality was-0. One month later the right coronary artery was ligated in 12 of these dogs and the mortality again was 0. The circumflex artery was ligated in 4 of the original group and the mortality again was 0. Thus a From the Western Reserve University, Cleveland, Ohio. This work was supported by grants from the TT. S. Public Health Service and the Cleveland Area Heart Society. Received for publication May 21, 1962. 412
Vol. 45. No. 3 March, 1963
S P L E E N GRAFTS U P O N HEART
413
second artery was ligated in 16 of the 30 dogs without mortality. It is obvious that this subject should receive further investigation because it might have practical application to humans with coronary artery disease. METHOD OF STUDY
The baekflow method of study was used. This method was described by Anrep and Ilausler 7 in 1928, by Mautz and Gregg8 in 1937, and also by Leighninger in 1959." The method involves ligation of the circumflex coronary artery at its origin. This artery is cut across distal to the ligature. The blood that escapes from the open end of the artery is the baekflow. It comes from the other patent coronary arteries by way of intercoronary anastomoses. This blood is available to the area of muscle that was made ischemic by the ligature on the artery. It escapes from the cut artery without going through the high-resistant capillary bed. If some of this blood did escape through the capillary bed it would be lost to the measurements. The amount of baekflow varies with aortic pressure. This was kept at a constant level of 100 mm. Hg. The pressure was reduced to this level by bleeding or was brought up to this level by a screw-clamp on the aorta. Three to six determinations for 30 seconds each were made at 5 minute intervals and the average figure became the baekflow. It was expressed in terms of cubic centimeters for one minute. Between determinations, the circumflex artery was perfused from the carotid artery to prevent ischemic changes in the muscle and also to prevent ventricular fibrillation. Average baekflow measurements in various groups of normal dogs showed some variations. Thus Leighninger 10 found the average to be 3.8 c.c. per minute on 67 normal dogs of which Eckstein did 41. One high measurement was 21.0 c.c. per minute. He also found the baekflow after the Beck operation was 8.5 c.c. per minute in 41 dogs.10 One high measurement in this group was 26.0 e.c. per minute. The conclusion was made that operation increased backflow by 4.7 c.c. per minute. In the study on nitroglycerin, the average baekflow in 21 normal dogs was 4.49 c.c. per minute and nitroglycerin increased this by 0.88 c.c. per minute. 9 The variation in the two groups of normal dogs was 0.7 c.c. (4.49 versus 3.8). These measurements on normal dogs are the basis for comparison with those in which spleen grafts were used. Leighninger and Eckstein11 reported average baekflow determinations of 6.9 c.c. per minute in 10 dogs in which a sham Beck 2 operation was done. This procedure consisted in placing a vein graft between aorta and coronary sinus and immediate ligation of the graft so that no blood flowed through the shunt. These authors also reported average baekflow of 4.3 c.c. per minute in 9 dogs whose hearts had been fibrillated by an outside current and then defibrillated by the open-chest method. The conclusion was made that trauma on the surface of the heart, such as that produced by surgical exposure and manipulation, produced an inflammatory reaction which in turn increased baekflow. It is not possible to make serial determinations on the same dog before and after placing spleen grafts on the heart because the manipulation in the artery and on the heart would augment baekflow for the second series of determinations. It is necessary to deal with
L E I G H N I N G E K ET AL.
414
J. Thoracic and Cardiovas. Surg.
average figures for the normal and compare these with average figures after the grafts were placed. EXPERIMENTS
1. Autogenous Splenic Pulp.—The left chest was opened. The diaphragm was incised and the spleen was removed. Part of the spleen was macerated into a pulp. The pericardium was incised for several centimeters and the pericardial cavity was filled with splenic pulp. The pericardium was closed with sutures. Backflow measurements were done 23 to 29 days later. The average backflow in 10 dogs was 7.4 c.c. per minute, with a range of 2.4 to 15.6. None of these grafts were successful " t a k e s . " Viable graft was not found. The reaction between heart and pericardium was mild; only a few adhesions were found between heart and pericardium. 2. Autogenous Slices of Spleen.—The left chest was opened. The diaphragm was opened. The spleen was delivered into the chest. About one fourth of the spleen was removed for grafting. The incised surface of the spleen was closed by sutures and returned to the abdomen. The incision in the diaphragm was closed. This portion of spleen was cut into thin slices and sutures were placed between these slices of spleen and pericardium so that a large area of pericardium was covered by these slices of spleen. The pericardium was then closed and the grafts were in contact with the heart. Positive " t a k e s " in 9: One or more slices of spleen appeared to be viable in 9 experiments. These positive takes were confirmed by microscopic sections. The average backflow in these experiments was 7.4 c.c. per minute, with a range of 2.4 to 16.4. The average period of time after grafting was 96 days, with a range of 66 and 125 days. The surface of the graft bled when the pericardium was separated from the graft. The graft was about one fourth the original size of the transplant. No " t a k e s " in 9: There were 9 experiments in which viable spleen was not found. These specimens were examined on an average of 75 days after they were placed, with a range of 60 to 88. In most of the specimens, adhesions were found between heart and pericardium. With several exceptions these were easily broken with the finger and the surface did not bleed. Dense adhesions were found in three experiments. The average backflow was 7.6 c.c. per minute, with a range of 3.8 to 13.8. 3. Autogenous Spleen Grafts With Intact Vascular Pedicle.—The left diaphragm was opened for about 3 to 4 cm. and the spleen was brought up through this opening. Approximately three fourths of the spleen was removed. The remaining portion of spleen was used as a graft with its blood supply intact. The graft was fashioned so as to get the longest possible pedicle. The opening in the diaphragm was made as small as possible and in some experiments sutures were placed between diaphragm and pedicle. The capsule of the graft which was to come into contact with the heart was abraded. The epieardium was abraded over the area of contact. Time was taken to stop the oozing of blood
Vol. 45, No. 3
March, 1963
S P L E E N GRAFTS U P O N H E A R T
415 *.*."
before the graft was placed. The pericardium was opened and pericardium and graft were sutured so that the abraded surface of the graft was in contact with the heart. The area of contact was about 5 cm. in each direction. Satisfactory backnow determinations were made in 13 experiments. The average determination was 8.3 c.c. per minute, with a range of 1.2 to 46.8. The average backnow without this one high determination was 5.3. The average duration of the experiment was 37 days, with a range of 32 to 41. All grafts were viable. In some of the experiments the spleen was not adherent to the heart. In most of the specimens the contact between graft and heart was slight and adhesions were easily broken. Dense adhesions were present in 3 specimens. The highest and the lowest backflows were in this small group. A mixture of barium sulfate and gelatin was injected into the coronary arteries in 9 specimens. This injection mass was thicker than blood and did not enter arteries less than 40 microns in diameter. These specimens were cleared.12 Injection-mass was found in 4 grafts which indicated the presence of vascular channels between heart and grafts. Intercoronary communications were present in 7 specimens. These were greater than normal and the conclusion is that they were produced by the operation. The mortality in these experiments was the significant figure of 30 per cent. Herniation was the usual cause of death. 4. Homologous Grafts.—The spleen of a dog was removed aseptically and cut into four parts. Each of these pieces was cut into thin slices and placed in normal sodium chloride solution or in Tyrode's solution containing penicillin. Each container was sealed and placed in the refrigerator. This material was used as graft within a period of 10 days. I t was applied as in Group 2 of the experiments. Backflow measurements were made 25 to 69 days later. The average backflow in 31 dogs was 9.0 c.c. per minute, with a range of 1.6 to 39.7. None of the grafts was viable. The grafted tissue disappeared leaving localized adhesions between heart and pericardium at the site of the grafts. In most of the specimens the reaction produced by these grafts was not severe. In several specimens dense adhesions were present. The surfaces did not bleed when separated by the finger. The coronary arteries were injected in 23 specimens. These were cleared. The site of the grafts was examined for injection-mass. Injection-mass was present at the site of the grafts in 2 specimens. It was not found in 21 specimens. The specimens were examined for intercoronary channels. These were estimated to be within the range of normal in 9 specimens. They were greater than normal in 14 specimens. The conclusion was that the presence of the homologous spleen grafts plus the reaction brought about by the operative procedure produced these intercoronary channels. These channels also explained the high backflow measurements. It is significant that this correlation existed between the amount of backflow and the demonstration of channels that transported this blood. The amount of backflow varies directly with the capacity of the intercoronary channels. DISCUSSION
Grafts of spleen placed on the surface of the heart increased backflow measurements over normal values. The average backflow in one series of normal dogs
L E I G H N I N G E R E T AL.
416
J. Thoracic and Cardiovas. Surg.
was 3.8 c.c. per minute; in another series of normal dogs it was 4.49 c.c. per minute. 1 0 ' J 1 Autogenous splenic pulp was placed in the pericardial cavity and backflow determinations were done several weeks later. These were increased by about 3 c.c. per minute to 7.4 c.c. Autogenous splenic pulp did not produce a single viable graft. Autogenous slices of spleen were placed on the heart in 18 experiments. Nine of these were positive takes confirmed by microscopic examination. Backflow was increased by about 3 c.c. per minute to 7.4 c.c. The size of the positive takes was about one fourth of the original graft. They became smaller and the development of new blood vessels was not significant. In 9 experiments, splenic tissue was not found at the site where grafts were placed. Splenic tissue had disappeared. The effect upon backflow was about the same as in the experiments in which splenic tissue was found. Autogenous spleen grafts with intact vascular pedicle were placed in 13 experiments. In these experiments the backflow was 8.3 c.c. which is an increase of 4.5 c.c. over normal average levels. Homologous grafts of spleen were placed in 31 experiments. None of these were positive takes. Backflow determinations were 9.0 c.c. The coronary arteries were injected in 23 of these experiments and the specimens were cleared. In 14 of these specimens, transport channels between coronary arteries were well above the average normal appearance. These channels accounted for the increased backflow. This correlation between anatomy and function is related to the genesis of anginal pain and fibrillating electricity (fatal heart attack) in the human because both of these are due to uneven distribution of blood in the heart muscle. CONCLUSIONS
Transplants of spleen were placed upon the surface of the heart. Backflow determinations in these experiments were 7.4 c.c. in one series of experiments and 9.0 c.c. in another series of experiments. In the presence of coronary artery occlusion these values give some measure of coronary collateral circulation. These backflow values are not higher than those produced by the Beck 1 operation. Spleen grafts have limited power of viability and no power for growth and the development of an independent blood supply, such as was occasionally found in the human when the spleen was fragmented by injury and particles seeded themselves and developed an independent blood supply. REFERENCES 1. Storsteen, K. A., and EeMine, W. H . : Rupture of the Spleen With Splenic Implants: Splenosis. Review of Literature and Report of a Case, Ann. Surg. 137: 551, 1953. 2. Marine, D., and Manley, 0 . T . : Influence of Age on the Permanence of Subcutaneous Autografts of the Spleen in Rabbits, Proc. Soc. Exper. Biol. & Med. 14: 123, 19161917. 3. Manley, O. T., and Marine, D . : The Transplantation of Splenic Tissue Into the Subcutaneous Fascia of the Abdomen in Rabbits, J . Exper. Med. 25: 619, 1917. 4. Perla, D . : The Regeneration of Autoplastic Splenic Transplants, Am. J . Path. 12: 665, 1936.
Vol. 45, No. 3 March, 1963
S P L E E N GRAFTS U P O N H E A E T
417
5. Garamella, J . J . , a n d Hay, L . J . : Autotransplantation of Spleen: Splenosis—Case Report and Preliminary Report of a n Experimental Study in Revascularization of the Heart, Ann. Surg. 140: 107, 1954. 6. Seltzer, E . I., and Maddock, S. J . : Technique for Supplementing Coronary Circulation by Means of a Splenic Graft, Rhode Island M. J . 39: 195, 1956. 7. Anrep, G. V., and Hausler, H . : The Coronary Circulation. I . The Effect of Changes of the Blood Pressure and of the Output of the Heart, J . Physiol. 6 6 : 357, 1928. 8. Mautz, F . R., and Gregg, D. E . : The Dynamics of Collateral Circulation Following Chronic Occlusion of Coronary Arteries, Proe. Soc. Exper. Biol. & Med. 3 6 : 797, 1937. 9. Leighninger, D. S., Rueger, R., and Beck, C. S.: Effect of Glyceryl Trinitrate (Nitroglycerin) on Arterial Blood Supply t o Ischemic Myocardium, Am. J . Cardiol. 3 : 638, 1959. 10. Leighninger, D. S.: A Laboratory and Clinical Evaluation of Operations for Coronary Artery Disease, J . THORACIC SURG. 30: 397, 1955.
11. Leighninger, D. S., and Eckstein, R. W . : Further Observations on Aorta to Coronary Sinus Anastomosis of Beck in Dogs, Proc. Soc. Exper. Biol. & Med. 87: 564, 1954. 12. Wolfe, K . : Plastic Embedded Hearts—Cleared and Corroded Specimens, A. M. A. Arch. Path. 6 1 : 153, 1956.