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Aneurysms of the Descending Thoracic Aorta
Aneurysms of the Descending Thoracic Aorta Marcus L. Dillon, M.D., W. Glenn Young, M.D., and Will C. Sealy, M.D.
D
uring the past eight years, we have operated on 34 patients with aneurysms of the descending thoracic aorta. These lesions can be successfully removed by providing protection from ischemic injury to the spinal cord and distal organs and by avoiding inordinate resistance to cardiac output during cross-clamping [2, 51. T h e etiology in our 34 patients was: arteriosclerosis, 16; trauma, 8; syphilis, 5 ; with coarctation, 2; with pseudocoarctation, 2; and following patent ductus ligation, 1. Partial pump oxygenator bypass from femoral vein to femoral artery was performed in 21, whereas 1 had pump bypass from left atrium to femoral artery. Nine patients had hypothermia between 30°C. and 33°C. Three did not require crossclamping of the aorta. ARTERIOSCLEROTIC ANEURYSMS
The 16 patients with arteriosclerotic aneurysms of the descending thoracic aorta ranged in age from 47 to 69 years. Investigation was initiated because of chest pain in 6, findings on routine chest film in 5, hemoptysis in 4, and cough with hoarseness in 1. Thirteen aneurysms were resected with Teflon grafts inserted in 12 and a Dacron graft in 1. Three had closure of the neck of the aneurysm. One operative death was due to hemorrhage, and 1 death eighteen days after operation was due to pneumonia with septicemia. Two late deaths occurred; 1 two months later from a pulmonary embolus and 1 three years after operation from coronary occlusion. Twelve patients are living; 6 between four and six years after operation and 6 between six months to two years after operation. Emphasis is placed on the 4 patients who presented with hemoptysis: All had the relatively uncommon finding of a false aneurysm into the parenchyma of the adjacent lung. From the Division of Thoracic Surgery, Veterans Administration Hospital, and Duke University Medical Center, Durham, N.C. Supported in part by a grant from the National Institutes of Health, US. Public Health Service Grant NO. HE 0782-13. presented at the Third Annual Meeting of The Society of Thoracic Surgeons, Kansas City, Mo., Jan. 23-25, 1967.
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Aneurysms of Descending Aorta
F I G . 1. Case 2, L. E . ( A ) Posteroanterior view of the chest gives the impression of a left hilar carcinoma; however, o n the lateral ( B ) view, the arrow points t o a displaced rim of calcium. ( C ) Angiogram outlines a saccular aneurysm with a small
false aneurysm into the lung parenchyma.
Case 1. L. S., a 60-year-old male, was admitted because of coughing up streaks of blood for two weeks. Chest films showed a 4 cm. mass at the hilum of the left lung. He was explored with extracorporeal pum standby. A saccular aneurysm of the midthoracic aorta with a 3 cm. base was c osed with interrupted sutures. The superior segment of the left lower lobe with the ruptured saccular aneurysm was removed. He did well for three years and died suddenly of a coronary thrombosis. Case 2. L. E., a 69-year-old woman, was admitted after five weeks of coughing up streaks and clots of blood. Chest films showed a density in the left posterior lung field, and no pulsation was seen on fluoroscopy. An intravenous angiogram showed a saccular midthoracic aneurysm (Fig. 1). At operation bloody fluid was found in the left chest associated with a saccular midthoracic aneurysm which had ruptured into the superior segment of the left lower lobe. The superior segment and aneurysm were resected and a Teflon graft was inserted under 34°C. hypothermia during 26 minutes of aortic occlusion. Excessive bleeding occurred during resection, and hypotension followed release of the aortic clamps. As the chest wound was being closed, the heart stopped: resuscitation was unsuccessful. Case 3. C. J., a 58-year-old male, was explored in 1954 at another hospital following an episode of hemoptysis of large quantities of bright red blood asso-
r
FIG. 2. Case 3, C . J . Superimposed drawings of the angiogram in ( A ) and ( B ) show that a large part of the mass is left upper lobe involvement. VOL.
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DILLON, YOUNG, AND SEALY ciated with shock. An aortic aneurysm was lound, and he was closed without resection. Following this he had intermittent episodes of hemoptysis, occasionally so severe as to cause shock and require blood transfusions. O n admission i n 1960, his chest films showed a density occupying the medial aspect of the left upper lung field. An angiogram showed saccular dilatation of the descending thoracic aorta with a dense, well-circumscribed mass around it (Fig. 2). T h e saccular aneurysm and left upper lobe with a false aneurysm were resected and the n'eck of the aneurysm sac was over-sewn using moderate hypothermia of 32°C. H e has remained well and working for six years. Case 4 . 13. H., a 68-year-old woman, was admitted i n March, 1966, with ii history of mild hemoptysis 16 clays previously. Chest films showed a hilar mass and vertebral erosion. At thoracotomy with 33°C. hypothermia, a ialse aneurysm was found in the adjacent lung. This was locally resected and the base ol the aneurysm was closed with mattress sutures. T h e patient has done well for six months. SYPHILITIC ANEURYSMS
Five patients aged 38 to 57 years had syphilitic aneurysnis (Fig. 3) resected and grafted. Two had marked hypertension of 180/110 mni. Hg. Two had Teflon tube grafts after resection, 1 had aneurysmorrhaphy with Teflon reinforcement, and 1 had excision of a saccular aneurysm with a Teflon patch graft. One hypertensive patient died a few hours after operation of progressive heart failure, and the other patient with hypertension died suddenly 32 months after operation of a coronary occlusion. Two patients died of hemorrhage at operation. and 1 is living and well seven months after operation. TRAUMATIC ANEURYSMS
Eight patients had traumatic aortic aneurysnis following deceleration injuries. All were located at the level of the ligamentum arterio-
F I G . 3 . T . K., a 57-year-old male with chest pain and a syphilitic aneurysm outlined by barium and demonstrating bone erosion in (C).
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Aneti ysms of Descending Aorta TABLE 1. TRAUMATIC DESCENDING THORACIC AORTIC ANEURYSMS
Pt.
Accident
Age
D. W.
Automobile Motorcycle Automobile Automobile Automobile Automobile Automobile Automobile
19 25 62 45
c. s.
R. S. T. K. P. D. A. T. J. s. H. M.
22
29 18 25
Injury to Op. Interval
7 yr. 2 yr.
Follow-up Living & well at 6 mo. Living & well at 3 mo. Living & well at 3% yr. Living &well at 6 yr. Living & well at 2 yr. Living & well at 4 yr. Living & well at 2?5 yr. Living & well at 7?4 yr.
3 yr. 8 yr. 3 yr. 13 yr. 1 mo. 9 mo.
sum. No operative or postoperative mortality occurred in this group, and they have all done well from three months to seven and one-half years (Table 1). Two patients demonstrated findings of aortic constriction. One of these presented as a problem of hypertension and suspected coarctation of the aorta two years after injury [3, 41. Case 5. C. S., a 19-year-old male, was referred for evaluation for hypertension with the history of an automobile accident two years previously. He was found to have a blood pressure of 160/100 mm. Hg in his arms and 140/100 mm. Hg in his legs. Routine chest films were not diagnostic for aortic deformity, and no rib notching was seen. Retrograde aortic catheterization revealed a gradient of 30 mm. Hg distal to the left subclavian artery, and a diagnosis of coarctation of the aorta was made. He was explored using partial extracorporeal bypass, and a false aneurysm was iound with a 5 cm. separation of the aortic lumen. The proximal and distal openings of the aneurysm were 1.5 cm. in diameter. Sections of the wall showed partly-organized thrombotic atheromatous material with no evidence of arterial wall. Three months after operation, he was well and his blood pressure was 135/70 mm. Hg. Case 6. H. M., a 25-year-old male, was injured in an automobile accident. On admission to the first hospital, he was paraplegic with a sensory level at T10 without a subarachnoid block. He had fullness of the episternal notch and bilaterally absent femoral pulses. Left femoral exploration the next day revealed no proximal or distal block to passage of a catheter. The femoral pulses gradually returned. Three weeks after injury, the blood pressure in the right arm was 210/170 mm. Hg and in the left arm 120/90 mm. Hg. Routine chest films demonstrated widening of the mediastinum. Two months after injury an aortogram was done in a second hospital which demonstrated an aneurysm in the region of the ligamentum arteriosum. The blood pressure in the arms was essentially equal at that time, 125/80 mm. Hg. The aneurysm was resected and grafted nine months after injury using left atrium-to-femoral artery bypass. He has had no difficulty since operation seven and one-half years ago other than residual paraplegia. FALSE ANEURYSM FOLLOWING LIGATION OF PATENT DUCTUS ARTERIOSUS
Case 7 . A. B., a 28-year-old white female, had a ligation of a patent ductus with umbilical tape in 1946 after receiving 6,050 units of penicillin over five weeks for subacute bacterial endocarditis. She did well for twelve years, when she developed anterior chest pain, shortness of breath, and swollen ankles. Chest films showed a 2.5 cm. mass in the left hilum with a rim of calcium. At VOL.
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DILLON, YOUNG, AND SEALY
operation under hypothermia of 32°C. a false aneurysm of the aorta at the site of ligation was plicated with interrupted sutures. The aortic pressure was reduced during the repair by cross-clamping the pulmonary artery for 2% minutes. She has continued to do well eight years following repair of the false aneurysm and twenty years following ligation of a patent ductus.
ANEURYSMS ASSOCIATED WITH COARCTATION AND PSEUDOCOARCTATION OF THE AORTA
Two patients with hypertension and absent and diminished leg pressure were found to have saccular aneurysms proximal to the coarctation. One patient was resected and a Teflon graft inserted six years ago under hypothermia to 34"C. and has remained normotensive with return of previously absent femoral pulses. The second patient had an aneurysm resected under hypothermia to 32°C.eight years ago with end-to-end anastomosis. She remained hypertensive for seven years and developed another aneurysm. She was reoperated using femoral vein-tofemoral artery partial bypass and was found to have a coarctation with poststenotic dilatation. This was resected, and a Teflon graft was inserted. She has done well for nine months and has remained normotensive (Fig. 4). Two patients with pseudocoarctation of the aorta with aneurysms of the aorta proximal to the ligamentum arteriosum presented with deformity of the aorta which resembled coarctation [6]. There was no gradient across these deformities at resection of the aneurysms, and division of the ligamentum arteriosum restored the normal anatomical configuration of the aorta. Table 2 gives the follow-up information on these patients.
FIG. 4. ( A ) Posteroanterior film of chest shows a saccular aneurysm of the aorta
between the left subclavian and ligamentum arteriosum in a 20-year-old female with hypertension. ( B ) Venous angiogram outlines the aneurysm but does not demonstrate a coarctation. (C)Aortogram done seven years after resection of the aneurysm shows kinking and coarctation of the aorta. Resection of the coarctation cured her hypertension. T h i s is similar to the kinking seen with pseudocoarctation.
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Aneurysms of Descending Aorta TABLE 2. ANEURYSMS ASSOCIATED WITH COARCTATION AND PSEUDOCOARCTATION OF THE AORTA
Pt./Age I Sex
Initial B.P.8
Final B.P.8
Follow-up
L. A., 24, M H. L., 20, F C. D., 51, F J. F., 37, F
160/100 1801100 130196 140/75
150180 120170 150190 140185
Living & well at 6 yr. Living &well at 8 yr. Living & well at 5 yr. Living &well at 1 yr.
"Blood pressure, mm. Hg.
DISCUSSION
Several interesting features of aneurysms of the descending thoracic aorta are illustrated by this series of patients. Four patients had arteriosclerotic aneurysms which ruptured into the adjacent lung, producing atelectasis, hemoptysis, and x-ray findings simulating carcinoma of the lung. Two patients with traumatic aneurysms presented with findings of stenosis of the aorta, and 1 of these developed an ischemic cord injury at the time of his accident. T h e patients with coarctation and pseudocoarctation all had aneurysms proximal to the ligamentum arteriosum.
;loo 50
FIG. 5. P u m p oxygenator and monitor systems with additional inflow lines t o he used if necessary for carotid perfusion.
DILLON, YOUNG, AND SEALY
We feel that the poor prognosis of an untreated aneurysm is an adequate indication for surgery. At operation, after obtaining proximal and distal control, we have often opened the aneurysm and inserted a graft leaving the posterior wall in place as described by 0. J. Creech in 1966 [l]. We prefer to use femoral vein-to-femoral artery partial bypass with a pump oxygenator with the capability of using hypothermia and additional inflow lines if the carotid vessels need perfusion to allow a more extensive resection [Z] (Fig. 5). Furthermore, we have the pump lines away from the operative field, a standard extracorporeal system to fit all occasions, and we avoid myocardial manipulation, atrial injury, or air embolization which is possible with left atrial-to-femoral artery bypass. T h e conduct of the perfusion is controlled by maintaining the blood pressure at normal levels in the proximal aorta by monitoring the blood pressure in the right arm. This results in a pump flow rate of about 2,000 ml. per minute and a resulting distal aortic blood pressure of about 50 to 70 mm. Hg [51. T h e mortality and morbidity is influenced by the etiology of the aneurysm. The group with traumatic aneurysms does best and represents the younger patients with relatively normal proximal and distal aortic tissue. Those with such destructive vascular disease as syphilis and hypertension do less well. REFERENCES 1. Creech, 0. J. Endo-aneurysmorrhaphy and treatment of aortic aneurysms. A n n . Surg. 164:935, 1966. 2. Hume, D. M., and Porter, R. R. Acute dissecting aortic aneurysms. Surgery 53: 122, 1963. 3. Laforet, E. G. Acute hypertension as a diagnostic clue in traumatic rupture of the thoracic aorta. Amer. J . Surg. 110:948, 1965. 4. Malm, J. R., and Deterling, R. A., Jr. Traumatic aneurysm of the thoracic aorta simulating coarctation. J . Thoruc. Curdiov. Surg. 40:271, 1960. 5. Morris, G. C., Jr., Witt, R. R., Cooley, D. A., Moyer, J. H., and De Bakey, M. E. Alterations in renal hemodynamics during controlled extracorporeal circulation in the surgical treatment oE aortic aneurysm. J. Thorac. Surg. 34:590, 1957. 6. Nasser, W. K., and Helmen, C. Kinking of the aortic arch (pseudocoarctation). Ann. Intern. M e d . 64:971, 1966. DZSCUSSZON
DR. WILLIAME. NEVILLE (Hines, Ill.): Unfortunately, after listening to Dr. Dillon’s excellent paper, I can find nothing to argue with him about. I certainly enjoyed his presentation, and although our experience with descending thoracic aneurysm is less than his, the pathological entities have been similar except for the traumatic group. I rise mainly to emphasize the use of partial bypass through the groin. We have tried left atrial bypass, hypothermia, and circumventing shunts, and we have abandoned all of these because of the inherent inadequacies of each. Although a left atrial bypass is relatively simple to perform, too much blood can 436
THE ANNALS OF THORACIC SURGERY
Aneurysms of Descending Aorta be removed from this side of the heart, thus lowering the cardiac output. Shunts are cumbersome, and certainly external hypothermia in this day and age probably should be abandoned for most of these patients. By far the easiest and simplest technique is cannulation of the femoral artery and vein in the groin with interposition of a small pump oxygenator. I n the event of hemorrhage, rapid replenishment of the circulating blood volume can be accomplished. The tubes are out of the operating field, and the perfusion is managed entirely from below while the operation proceeds in the chest. We have employed gravity drainage into the disc oxygenator or the Travenol bag filled with Ringer’s lactate solution. The venous drainage is controlled by a screw clamp on the venous line, so that the output of the heart maintains perfusion of the upper part of the body and the pump oxygenator supplies the kidneys and the spinal cord with blood. If properly managed, the desired quantities of blood can be removed and reinfused to sustain viability below the clamp. As a rule, the arterial pump flow is set to deliver 1,500 ml. per minute, and the cardiac output is monitored with the clamp on the venous line. The other point to which Dr. Dillon alluded is that it is not necessary to resect the aneurysm. I t is our policy to isolate the aorta above and below the lesion and, with the onset of perfusion, to apply the clamps, open the aneurysm longitudinally, and suture the intercostal vessels inside the aorta. In this manner, large areas of the mediastinum which subsequently may bleed after the perfusion are not opened. I think this has been a very valid argument in the past against the use of partial bypass, since heparinization was needed and the postoperative bleeding from the mediastinum was difficult to control. This is obviated when large areas of the mediastinum are not opened.
DR.JURO WADA(Sapporo, Japan): The speaker is to be congratulated for his nice presentation. Electrically induced fibrillation has been used by us routinely in more than 700 open-heart operations. We also have found that it is very useful in controlling hemorrhage. Six cases of uncontrollable hemorrhage which took place during operations were well controlled by the use of the induced fibrillation. Electrically induced fibrillation can be used in surgically treating aortic aneurysms without use of hypothermia or of a pump oxygenator. I wish to present 2 such cases. The first case was a 50-year-old male showing a large massive shadow in the right upper posterior thoracic cage; the possible diagnosis was mediastinal tumor surrounded by esophagus, trachea, and aortic arch. Right anterior thoracotomy through the third intercostal space was done. A huge, pulsating mass was found originating from the left thorax. We then opened the left chest through the left fourth intercostal space and found that the aneurysm originated from the aorta just distal to the left subclavian artery and extended into the right thorax behind the aortic arch. The aortic arch proximal to it and the descending aorta distal to it were freed. Electrical fibrillation was induced. Immediately occluding clamps were placed proximal to and distal to the aneurysm. The aneurysm was incised. The clot inside the aneurysm and aorta was removed and the aneurysm amputated. The aorta was reconstituted temporarily by closing the bowl-shaped opening with the use of a dozen Allis forceps. At this point the two occluding forceps on the aorta were removed, and direct current shock was given. Sinus rhythm and good pressure were instantly recovered. Then Allis forceps were replaced leisurely with stitches; that is, an aortorrhaphy was completed. The aneurysmal sac was left behind. I t is now over one year after the surgery, and the patient is in good shape. The second case, a male 55 years of age, was diagnosed as having a huge aortic arch aneurysm invading the right innominate artery. A soft, pulsating tumor was palpable at the left sternoclavicular junction. X-rays showed an erosion defect of the left side of sternal manubrium. When approached through the right fourth anterior intercostal space, the aneurysm was found to be densely adherent, and so a left fourth intercostal incision was
DILLON, YOUNG, AND SEALY added and the sternum was transected. The skin was freed from the bony chest up to the neck. Using a wire saw, the fourth, third, second, and first ribs and clavicles were cut bilaterally. The sternal notch was dissected. This left us with a floating, square-shaped bony plate which was attached to the aneurysm. The aneurysm extended to the root of the left common carotid artery. Fibrillation was induced, and the ascending aorta, the aortic arch just proximal to the left common carotid artery, and the innominate artery were cross-clamped. The bony plate was removed by amputating the aneurysm. A large clot inside was scraped out. Using the remaining aortic wall, the aortic arch was temporarily reconstituted with a dozen Allis forceps. Sinus rhythm and preoperative blood pressure were quickly restored. The Allis forceps were then replaced by multiple interrupted sutures. A prosthetic vascular graft was placed between the distal end of the innominate artery and the newly reconstructed aortic arch. The anterior chest wall was reconstructed by placing the bony plate in its original site. Clavicles were sutured with wire. The patient made a nice recovery. These two clinical cases clearly indicate that electrically induced fibrillation can be used safely in aortic aneurysm surgery instead of using general hypothermia or a pump oxygenator. There is no report in the literature of this new technique. DR. VINCENT L. GOTT(Baltimore, Md.): Dr. Neville suggested that probably the simplest way to resect and replace descending thoracic aortic aneurysms is by cannulating both the femoral artery and femoral vein with a pump bypass, and I would like to suggest that it would be even simpler to eliminate the pump and eliminate heparinization by using a graphite- and heparin-coated shunt. We became interested in this technique a little over a year ago, and the technique was worked out in our research laboratory by Dr. Sankaran Valiathan in 15 animals. In the technique worked out in the research laboratory, a graphitebenzalkonium-heparin (GBH) coated polyvinyl catheter was placed in the left subclavian artery, and a similar catheter was placed in the descending thoracic aorta through a purse-string suture just above the diaphragm. These two cannulas were joined together with a GBH-coated stainless-steel connector. Then the descending thoracic aorta was doubly clamped for one hour and the aorta divided and reanastomosed during this time. With this technique, satisfactory pressures were maintained above and below the aortic clamps. We recently had a 78-year-old woman with a gigantic aneurysm of the descending thoracic aorta that was pressing on the sixth and seventh ribs; we felt that the above technique would be suitable for resection of this aneurysm. We cannulated the subclavian artery with a GBH-coated Bard catheter and similarly cannulated the left femoral artery with a catheter. A %-inch length of GBH-coated polyvinyl tubing was interposed between these catheters, and the connections were made with GBH-coated stainless-steel connectors. I n this patient the aneurysm extended all the way from the subclavian artery to the diaphragm, and we had to incise the diaphragm to get adequate exposure distally. In this particular case we were able to cannulate the subclavian artery and place our proximal clamp across the aorta just distal to the subclavian artery. For aneurysms extending proximal to the subclavian artery, we would place our proximal cannula through a purse-string in the transverse arch of the aorta. We believe that the operative procedure in this patient was greatly simplified in that heparinization was not required and in that we had a very dry operative field even though there was very extensive mediastinal dissection. Similarly, the elimination of a blood pump greatly simplified the procedure. This patient is now approximately six months postoperative and is doing very well. We plan to use this technique routinely for descending thoracic aortic aneurysms. DR. DILLON:I would like to thank those who have discussed the paper. Certainly there are times when it stretches one’s ingenuity to find ways to handle these problems.
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THE ANNAIS
OF THORACIC SURGERY
D
uring the past eight years, we have operated on 34 patients with aneurysms of the descending thoracic aorta. These lesions can be successfully removed by providing protection from ischemic injury to the spinal cord and distal organs and by avoiding inordinate resistance to cardiac output during cross-clamping [2, 51. T h e etiology in our 34 patients was: arteriosclerosis, 16; trauma, 8; syphilis, 5 ; with coarctation, 2; with pseudocoarctation, 2; and following patent ductus ligation, 1. Partial pump oxygenator bypass from femoral vein to femoral artery was performed in 21, whereas 1 had pump bypass from left atrium to femoral artery. Nine patients had hypothermia between 30°C. and 33°C. Three did not require crossclamping of the aorta. ARTERIOSCLEROTIC ANEURYSMS
The 16 patients with arteriosclerotic aneurysms of the descending thoracic aorta ranged in age from 47 to 69 years. Investigation was initiated because of chest pain in 6, findings on routine chest film in 5, hemoptysis in 4, and cough with hoarseness in 1. Thirteen aneurysms were resected with Teflon grafts inserted in 12 and a Dacron graft in 1. Three had closure of the neck of the aneurysm. One operative death was due to hemorrhage, and 1 death eighteen days after operation was due to pneumonia with septicemia. Two late deaths occurred; 1 two months later from a pulmonary embolus and 1 three years after operation from coronary occlusion. Twelve patients are living; 6 between four and six years after operation and 6 between six months to two years after operation. Emphasis is placed on the 4 patients who presented with hemoptysis: All had the relatively uncommon finding of a false aneurysm into the parenchyma of the adjacent lung. From the Division of Thoracic Surgery, Veterans Administration Hospital, and Duke University Medical Center, Durham, N.C. Supported in part by a grant from the National Institutes of Health, US. Public Health Service Grant NO. HE 0782-13. presented at the Third Annual Meeting of The Society of Thoracic Surgeons, Kansas City, Mo., Jan. 23-25, 1967.
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Aneurysms of Descending Aorta
F I G . 1. Case 2, L. E . ( A ) Posteroanterior view of the chest gives the impression of a left hilar carcinoma; however, o n the lateral ( B ) view, the arrow points t o a displaced rim of calcium. ( C ) Angiogram outlines a saccular aneurysm with a small
false aneurysm into the lung parenchyma.
Case 1. L. S., a 60-year-old male, was admitted because of coughing up streaks of blood for two weeks. Chest films showed a 4 cm. mass at the hilum of the left lung. He was explored with extracorporeal pum standby. A saccular aneurysm of the midthoracic aorta with a 3 cm. base was c osed with interrupted sutures. The superior segment of the left lower lobe with the ruptured saccular aneurysm was removed. He did well for three years and died suddenly of a coronary thrombosis. Case 2. L. E., a 69-year-old woman, was admitted after five weeks of coughing up streaks and clots of blood. Chest films showed a density in the left posterior lung field, and no pulsation was seen on fluoroscopy. An intravenous angiogram showed a saccular midthoracic aneurysm (Fig. 1). At operation bloody fluid was found in the left chest associated with a saccular midthoracic aneurysm which had ruptured into the superior segment of the left lower lobe. The superior segment and aneurysm were resected and a Teflon graft was inserted under 34°C. hypothermia during 26 minutes of aortic occlusion. Excessive bleeding occurred during resection, and hypotension followed release of the aortic clamps. As the chest wound was being closed, the heart stopped: resuscitation was unsuccessful. Case 3. C. J., a 58-year-old male, was explored in 1954 at another hospital following an episode of hemoptysis of large quantities of bright red blood asso-
r
FIG. 2. Case 3, C . J . Superimposed drawings of the angiogram in ( A ) and ( B ) show that a large part of the mass is left upper lobe involvement. VOL.
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DILLON, YOUNG, AND SEALY ciated with shock. An aortic aneurysm was lound, and he was closed without resection. Following this he had intermittent episodes of hemoptysis, occasionally so severe as to cause shock and require blood transfusions. O n admission i n 1960, his chest films showed a density occupying the medial aspect of the left upper lung field. An angiogram showed saccular dilatation of the descending thoracic aorta with a dense, well-circumscribed mass around it (Fig. 2). T h e saccular aneurysm and left upper lobe with a false aneurysm were resected and the n'eck of the aneurysm sac was over-sewn using moderate hypothermia of 32°C. H e has remained well and working for six years. Case 4 . 13. H., a 68-year-old woman, was admitted i n March, 1966, with ii history of mild hemoptysis 16 clays previously. Chest films showed a hilar mass and vertebral erosion. At thoracotomy with 33°C. hypothermia, a ialse aneurysm was found in the adjacent lung. This was locally resected and the base ol the aneurysm was closed with mattress sutures. T h e patient has done well for six months. SYPHILITIC ANEURYSMS
Five patients aged 38 to 57 years had syphilitic aneurysnis (Fig. 3) resected and grafted. Two had marked hypertension of 180/110 mni. Hg. Two had Teflon tube grafts after resection, 1 had aneurysmorrhaphy with Teflon reinforcement, and 1 had excision of a saccular aneurysm with a Teflon patch graft. One hypertensive patient died a few hours after operation of progressive heart failure, and the other patient with hypertension died suddenly 32 months after operation of a coronary occlusion. Two patients died of hemorrhage at operation. and 1 is living and well seven months after operation. TRAUMATIC ANEURYSMS
Eight patients had traumatic aortic aneurysnis following deceleration injuries. All were located at the level of the ligamentum arterio-
F I G . 3 . T . K., a 57-year-old male with chest pain and a syphilitic aneurysm outlined by barium and demonstrating bone erosion in (C).
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Aneti ysms of Descending Aorta TABLE 1. TRAUMATIC DESCENDING THORACIC AORTIC ANEURYSMS
Pt.
Accident
Age
D. W.
Automobile Motorcycle Automobile Automobile Automobile Automobile Automobile Automobile
19 25 62 45
c. s.
R. S. T. K. P. D. A. T. J. s. H. M.
22
29 18 25
Injury to Op. Interval
7 yr. 2 yr.
Follow-up Living & well at 6 mo. Living & well at 3 mo. Living & well at 3% yr. Living &well at 6 yr. Living & well at 2 yr. Living & well at 4 yr. Living & well at 2?5 yr. Living & well at 7?4 yr.
3 yr. 8 yr. 3 yr. 13 yr. 1 mo. 9 mo.
sum. No operative or postoperative mortality occurred in this group, and they have all done well from three months to seven and one-half years (Table 1). Two patients demonstrated findings of aortic constriction. One of these presented as a problem of hypertension and suspected coarctation of the aorta two years after injury [3, 41. Case 5. C. S., a 19-year-old male, was referred for evaluation for hypertension with the history of an automobile accident two years previously. He was found to have a blood pressure of 160/100 mm. Hg in his arms and 140/100 mm. Hg in his legs. Routine chest films were not diagnostic for aortic deformity, and no rib notching was seen. Retrograde aortic catheterization revealed a gradient of 30 mm. Hg distal to the left subclavian artery, and a diagnosis of coarctation of the aorta was made. He was explored using partial extracorporeal bypass, and a false aneurysm was iound with a 5 cm. separation of the aortic lumen. The proximal and distal openings of the aneurysm were 1.5 cm. in diameter. Sections of the wall showed partly-organized thrombotic atheromatous material with no evidence of arterial wall. Three months after operation, he was well and his blood pressure was 135/70 mm. Hg. Case 6. H. M., a 25-year-old male, was injured in an automobile accident. On admission to the first hospital, he was paraplegic with a sensory level at T10 without a subarachnoid block. He had fullness of the episternal notch and bilaterally absent femoral pulses. Left femoral exploration the next day revealed no proximal or distal block to passage of a catheter. The femoral pulses gradually returned. Three weeks after injury, the blood pressure in the right arm was 210/170 mm. Hg and in the left arm 120/90 mm. Hg. Routine chest films demonstrated widening of the mediastinum. Two months after injury an aortogram was done in a second hospital which demonstrated an aneurysm in the region of the ligamentum arteriosum. The blood pressure in the arms was essentially equal at that time, 125/80 mm. Hg. The aneurysm was resected and grafted nine months after injury using left atrium-to-femoral artery bypass. He has had no difficulty since operation seven and one-half years ago other than residual paraplegia. FALSE ANEURYSM FOLLOWING LIGATION OF PATENT DUCTUS ARTERIOSUS
Case 7 . A. B., a 28-year-old white female, had a ligation of a patent ductus with umbilical tape in 1946 after receiving 6,050 units of penicillin over five weeks for subacute bacterial endocarditis. She did well for twelve years, when she developed anterior chest pain, shortness of breath, and swollen ankles. Chest films showed a 2.5 cm. mass in the left hilum with a rim of calcium. At VOL.
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operation under hypothermia of 32°C. a false aneurysm of the aorta at the site of ligation was plicated with interrupted sutures. The aortic pressure was reduced during the repair by cross-clamping the pulmonary artery for 2% minutes. She has continued to do well eight years following repair of the false aneurysm and twenty years following ligation of a patent ductus.
ANEURYSMS ASSOCIATED WITH COARCTATION AND PSEUDOCOARCTATION OF THE AORTA
Two patients with hypertension and absent and diminished leg pressure were found to have saccular aneurysms proximal to the coarctation. One patient was resected and a Teflon graft inserted six years ago under hypothermia to 34"C. and has remained normotensive with return of previously absent femoral pulses. The second patient had an aneurysm resected under hypothermia to 32°C.eight years ago with end-to-end anastomosis. She remained hypertensive for seven years and developed another aneurysm. She was reoperated using femoral vein-tofemoral artery partial bypass and was found to have a coarctation with poststenotic dilatation. This was resected, and a Teflon graft was inserted. She has done well for nine months and has remained normotensive (Fig. 4). Two patients with pseudocoarctation of the aorta with aneurysms of the aorta proximal to the ligamentum arteriosum presented with deformity of the aorta which resembled coarctation [6]. There was no gradient across these deformities at resection of the aneurysms, and division of the ligamentum arteriosum restored the normal anatomical configuration of the aorta. Table 2 gives the follow-up information on these patients.
FIG. 4. ( A ) Posteroanterior film of chest shows a saccular aneurysm of the aorta
between the left subclavian and ligamentum arteriosum in a 20-year-old female with hypertension. ( B ) Venous angiogram outlines the aneurysm but does not demonstrate a coarctation. (C)Aortogram done seven years after resection of the aneurysm shows kinking and coarctation of the aorta. Resection of the coarctation cured her hypertension. T h i s is similar to the kinking seen with pseudocoarctation.
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Aneurysms of Descending Aorta TABLE 2. ANEURYSMS ASSOCIATED WITH COARCTATION AND PSEUDOCOARCTATION OF THE AORTA
Pt./Age I Sex
Initial B.P.8
Final B.P.8
Follow-up
L. A., 24, M H. L., 20, F C. D., 51, F J. F., 37, F
160/100 1801100 130196 140/75
150180 120170 150190 140185
Living & well at 6 yr. Living &well at 8 yr. Living & well at 5 yr. Living &well at 1 yr.
"Blood pressure, mm. Hg.
DISCUSSION
Several interesting features of aneurysms of the descending thoracic aorta are illustrated by this series of patients. Four patients had arteriosclerotic aneurysms which ruptured into the adjacent lung, producing atelectasis, hemoptysis, and x-ray findings simulating carcinoma of the lung. Two patients with traumatic aneurysms presented with findings of stenosis of the aorta, and 1 of these developed an ischemic cord injury at the time of his accident. T h e patients with coarctation and pseudocoarctation all had aneurysms proximal to the ligamentum arteriosum.
;loo 50
FIG. 5. P u m p oxygenator and monitor systems with additional inflow lines t o he used if necessary for carotid perfusion.
DILLON, YOUNG, AND SEALY
We feel that the poor prognosis of an untreated aneurysm is an adequate indication for surgery. At operation, after obtaining proximal and distal control, we have often opened the aneurysm and inserted a graft leaving the posterior wall in place as described by 0. J. Creech in 1966 [l]. We prefer to use femoral vein-to-femoral artery partial bypass with a pump oxygenator with the capability of using hypothermia and additional inflow lines if the carotid vessels need perfusion to allow a more extensive resection [Z] (Fig. 5). Furthermore, we have the pump lines away from the operative field, a standard extracorporeal system to fit all occasions, and we avoid myocardial manipulation, atrial injury, or air embolization which is possible with left atrial-to-femoral artery bypass. T h e conduct of the perfusion is controlled by maintaining the blood pressure at normal levels in the proximal aorta by monitoring the blood pressure in the right arm. This results in a pump flow rate of about 2,000 ml. per minute and a resulting distal aortic blood pressure of about 50 to 70 mm. Hg [51. T h e mortality and morbidity is influenced by the etiology of the aneurysm. The group with traumatic aneurysms does best and represents the younger patients with relatively normal proximal and distal aortic tissue. Those with such destructive vascular disease as syphilis and hypertension do less well. REFERENCES 1. Creech, 0. J. Endo-aneurysmorrhaphy and treatment of aortic aneurysms. A n n . Surg. 164:935, 1966. 2. Hume, D. M., and Porter, R. R. Acute dissecting aortic aneurysms. Surgery 53: 122, 1963. 3. Laforet, E. G. Acute hypertension as a diagnostic clue in traumatic rupture of the thoracic aorta. Amer. J . Surg. 110:948, 1965. 4. Malm, J. R., and Deterling, R. A., Jr. Traumatic aneurysm of the thoracic aorta simulating coarctation. J . Thoruc. Curdiov. Surg. 40:271, 1960. 5. Morris, G. C., Jr., Witt, R. R., Cooley, D. A., Moyer, J. H., and De Bakey, M. E. Alterations in renal hemodynamics during controlled extracorporeal circulation in the surgical treatment oE aortic aneurysm. J. Thorac. Surg. 34:590, 1957. 6. Nasser, W. K., and Helmen, C. Kinking of the aortic arch (pseudocoarctation). Ann. Intern. M e d . 64:971, 1966. DZSCUSSZON
DR. WILLIAME. NEVILLE (Hines, Ill.): Unfortunately, after listening to Dr. Dillon’s excellent paper, I can find nothing to argue with him about. I certainly enjoyed his presentation, and although our experience with descending thoracic aneurysm is less than his, the pathological entities have been similar except for the traumatic group. I rise mainly to emphasize the use of partial bypass through the groin. We have tried left atrial bypass, hypothermia, and circumventing shunts, and we have abandoned all of these because of the inherent inadequacies of each. Although a left atrial bypass is relatively simple to perform, too much blood can 436
THE ANNALS OF THORACIC SURGERY
Aneurysms of Descending Aorta be removed from this side of the heart, thus lowering the cardiac output. Shunts are cumbersome, and certainly external hypothermia in this day and age probably should be abandoned for most of these patients. By far the easiest and simplest technique is cannulation of the femoral artery and vein in the groin with interposition of a small pump oxygenator. I n the event of hemorrhage, rapid replenishment of the circulating blood volume can be accomplished. The tubes are out of the operating field, and the perfusion is managed entirely from below while the operation proceeds in the chest. We have employed gravity drainage into the disc oxygenator or the Travenol bag filled with Ringer’s lactate solution. The venous drainage is controlled by a screw clamp on the venous line, so that the output of the heart maintains perfusion of the upper part of the body and the pump oxygenator supplies the kidneys and the spinal cord with blood. If properly managed, the desired quantities of blood can be removed and reinfused to sustain viability below the clamp. As a rule, the arterial pump flow is set to deliver 1,500 ml. per minute, and the cardiac output is monitored with the clamp on the venous line. The other point to which Dr. Dillon alluded is that it is not necessary to resect the aneurysm. I t is our policy to isolate the aorta above and below the lesion and, with the onset of perfusion, to apply the clamps, open the aneurysm longitudinally, and suture the intercostal vessels inside the aorta. In this manner, large areas of the mediastinum which subsequently may bleed after the perfusion are not opened. I think this has been a very valid argument in the past against the use of partial bypass, since heparinization was needed and the postoperative bleeding from the mediastinum was difficult to control. This is obviated when large areas of the mediastinum are not opened.
DR.JURO WADA(Sapporo, Japan): The speaker is to be congratulated for his nice presentation. Electrically induced fibrillation has been used by us routinely in more than 700 open-heart operations. We also have found that it is very useful in controlling hemorrhage. Six cases of uncontrollable hemorrhage which took place during operations were well controlled by the use of the induced fibrillation. Electrically induced fibrillation can be used in surgically treating aortic aneurysms without use of hypothermia or of a pump oxygenator. I wish to present 2 such cases. The first case was a 50-year-old male showing a large massive shadow in the right upper posterior thoracic cage; the possible diagnosis was mediastinal tumor surrounded by esophagus, trachea, and aortic arch. Right anterior thoracotomy through the third intercostal space was done. A huge, pulsating mass was found originating from the left thorax. We then opened the left chest through the left fourth intercostal space and found that the aneurysm originated from the aorta just distal to the left subclavian artery and extended into the right thorax behind the aortic arch. The aortic arch proximal to it and the descending aorta distal to it were freed. Electrical fibrillation was induced. Immediately occluding clamps were placed proximal to and distal to the aneurysm. The aneurysm was incised. The clot inside the aneurysm and aorta was removed and the aneurysm amputated. The aorta was reconstituted temporarily by closing the bowl-shaped opening with the use of a dozen Allis forceps. At this point the two occluding forceps on the aorta were removed, and direct current shock was given. Sinus rhythm and good pressure were instantly recovered. Then Allis forceps were replaced leisurely with stitches; that is, an aortorrhaphy was completed. The aneurysmal sac was left behind. I t is now over one year after the surgery, and the patient is in good shape. The second case, a male 55 years of age, was diagnosed as having a huge aortic arch aneurysm invading the right innominate artery. A soft, pulsating tumor was palpable at the left sternoclavicular junction. X-rays showed an erosion defect of the left side of sternal manubrium. When approached through the right fourth anterior intercostal space, the aneurysm was found to be densely adherent, and so a left fourth intercostal incision was
DILLON, YOUNG, AND SEALY added and the sternum was transected. The skin was freed from the bony chest up to the neck. Using a wire saw, the fourth, third, second, and first ribs and clavicles were cut bilaterally. The sternal notch was dissected. This left us with a floating, square-shaped bony plate which was attached to the aneurysm. The aneurysm extended to the root of the left common carotid artery. Fibrillation was induced, and the ascending aorta, the aortic arch just proximal to the left common carotid artery, and the innominate artery were cross-clamped. The bony plate was removed by amputating the aneurysm. A large clot inside was scraped out. Using the remaining aortic wall, the aortic arch was temporarily reconstituted with a dozen Allis forceps. Sinus rhythm and preoperative blood pressure were quickly restored. The Allis forceps were then replaced by multiple interrupted sutures. A prosthetic vascular graft was placed between the distal end of the innominate artery and the newly reconstructed aortic arch. The anterior chest wall was reconstructed by placing the bony plate in its original site. Clavicles were sutured with wire. The patient made a nice recovery. These two clinical cases clearly indicate that electrically induced fibrillation can be used safely in aortic aneurysm surgery instead of using general hypothermia or a pump oxygenator. There is no report in the literature of this new technique. DR. VINCENT L. GOTT(Baltimore, Md.): Dr. Neville suggested that probably the simplest way to resect and replace descending thoracic aortic aneurysms is by cannulating both the femoral artery and femoral vein with a pump bypass, and I would like to suggest that it would be even simpler to eliminate the pump and eliminate heparinization by using a graphite- and heparin-coated shunt. We became interested in this technique a little over a year ago, and the technique was worked out in our research laboratory by Dr. Sankaran Valiathan in 15 animals. In the technique worked out in the research laboratory, a graphitebenzalkonium-heparin (GBH) coated polyvinyl catheter was placed in the left subclavian artery, and a similar catheter was placed in the descending thoracic aorta through a purse-string suture just above the diaphragm. These two cannulas were joined together with a GBH-coated stainless-steel connector. Then the descending thoracic aorta was doubly clamped for one hour and the aorta divided and reanastomosed during this time. With this technique, satisfactory pressures were maintained above and below the aortic clamps. We recently had a 78-year-old woman with a gigantic aneurysm of the descending thoracic aorta that was pressing on the sixth and seventh ribs; we felt that the above technique would be suitable for resection of this aneurysm. We cannulated the subclavian artery with a GBH-coated Bard catheter and similarly cannulated the left femoral artery with a catheter. A %-inch length of GBH-coated polyvinyl tubing was interposed between these catheters, and the connections were made with GBH-coated stainless-steel connectors. I n this patient the aneurysm extended all the way from the subclavian artery to the diaphragm, and we had to incise the diaphragm to get adequate exposure distally. In this particular case we were able to cannulate the subclavian artery and place our proximal clamp across the aorta just distal to the subclavian artery. For aneurysms extending proximal to the subclavian artery, we would place our proximal cannula through a purse-string in the transverse arch of the aorta. We believe that the operative procedure in this patient was greatly simplified in that heparinization was not required and in that we had a very dry operative field even though there was very extensive mediastinal dissection. Similarly, the elimination of a blood pump greatly simplified the procedure. This patient is now approximately six months postoperative and is doing very well. We plan to use this technique routinely for descending thoracic aortic aneurysms. DR. DILLON:I would like to thank those who have discussed the paper. Certainly there are times when it stretches one’s ingenuity to find ways to handle these problems.
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OF THORACIC SURGERY