Coarctation of the Abdominal Aorta

Coarctation of the Abdominal Aorta* Report of a Case and Review of the Literature RoNALD

J.

BAlllD, M.o.,** Cut:oF.

J.

LABROSSF., I\I.D.,t AND JoHN R . EvANS, M.o.tt

Toronto, Ontario, Canada

C

tion, aortic valve closure was accentuated and a soft protodiastolic filling sound was followed hy a loud presystolic gallop. Thrre was a Grade II out of I\' ejection systolic murmur heard along tht> ll'ft st<"mal hordf'r and o\'er thr carotid and subclavian vessels. In the epigastrium, a palpablt> systolic thrill and continuous murmur were pressent. The continuous murrnur was also heard in the back at the level of the lOth to 12th thoracic \'l'rtebrae. Intercostal \'t>ssels were felt at tht> lowt>r borders of the fifth to tt>nth ribs and dilated pulsating arteries wert' palpahlr at the lower costal margin anteriorly. The legs appeared normally developed with good nutrition of the skin, hut the arterial pulses wt>re absent distal to tht> femoral level as noted. The remaindl'r of thf' physical examination was negati\·e. Electrocardiograms showed ll'ft ,·entricular hypt>rtrophy by voltage without T wave inwrsion in the left precordial leads at rest or after exertion. Chest ro«.>ntgenograms showed notching of the inferior borders of the fifth to ninth ribs. The ascending aorta was prominent to thl' right,

OARCTATIO:o-: USUAI.I.Y OCCURS l!li THE

thoracic rather than the abdominal aorta. \\1 hen the coarctation occurs in the abdominal aorta, it may be congenital or acquired, localized or difful'e, involve the aorta alone, or also narrow the gastrointestinal or renal arteries. In this article, the literature on coarctation of the abdominal aorta is re\·iewed and a cal'e successfullv treated by surgery is reported. The patient had three separate coarctations of the abdominal aorta, stenosis of the origins of both renal arteries, thrombosis of the superior mesenteric artery, and an abdominal aortic aneurysm. CASE

REPORT

The patient. L.M .. a 19-yrar-old white man. was referred for consultation in November. JI)6J when a routine pre-t>mployrnent examination rrvealed hypertrnsion, an abdominal bruit. and reduced femoral artrrial pulsations. Familv history was non-contributor.·. Th.-rr ,,·as no hit !rver. Hr was no.t limitt>d hy symptoms, hut on direct qurstioning admitted weakness and fatigue in thl' legs with strenuous exercise and nausea aftrr largr mrals. The patil'nt was well drwloped. 69 i~chl's tall. and weight•d 140 pounds. Th.- optic fundi wrrr hypt>remic and the rt'tinal vessels more tortuous and morl' prominl'nt than usual. Blood pri'SSllrl' was 210/ 110 in the right arm. 200/ 105 in th<' lt"ft arm and 110/ 90-95 in both legs. Femoral pulses were barely perceptible and no distal pulses were detected. The heart was slightly enlarged with marked lf'ft ventricular thrust and palpable presystolic filling impulse at the apex. On auscula•From the Department of Medicine and Surgery, Vni,·enity of Toronto, Toronto General Hospital and Toronto Westem Hospital. ••Attending Surgeon, Toronto Westem Hospital: Clinical Teacher, Department of Surgery, L'nivenity of Toronto. tAssistant Resident , Cardiovascular Surgery. Toronto G.-n.,ral Hospital. ttPhysician, Toronto General Hospital : Associate, Department of Medicine, Cnivenity of Toronto.

I : X-ray film of chest showing notching of the fifth to t~nth ribs.

FtGt.:RE

517

BAIRD, LABROSSE A!'ID

EVA~S

Diseases of the Chest

FtGt:RE 2 : Antero-posterior and lateral views of abdomen showing calcified aneurysm in front of the second lumbar vertebra. but no enlargement of the aortic knuckle or descending thoracic aorta was noted. There wa s a round arl'a of eggshell cakification situalt•d anteriorly to the second lumbar vertebra ; it mea-

sured 3 em . in diametl'r ( Fig. I ). Aortography indicated that the thoracic aorta distal to the left subclavian artery was moderately hypoplastic. Both internal mammary arteries werr greatly

FtGURE 3: Aortogram showing hypoplastic lower thoracic aorta, enlarged intercostal arteries, and the lint coarctation just above the ca:liac axis.

Volum< 48, No. ' No,·
COARCTATIOj'; OF THE ABOOMI:-JAL AORTA

dila1ed, as were 1he six1h 10 1en1h imercoslal arleries.. The aorta narrowed al a poim immedialely above lhl' caliac ar1ery and 1he ~plenic and hepalic branches of 1he caliac ar1ery were large. No superior mesemeric ariCI)' wa~ \'isible. A localized area of s1enosis al 1he origin of 1he righl renal anery was apparen1, bu1 lhl' lef1 renal arlery was of normal calibre. The calcified ma~~ situalcd imnwdialt'l\' dis1al lo 1ht' ori~in of 1he right renal artery did no1 fill wi1h co~lra~l mrdia ( Fig. 2 ) . The inferior ml'~meric ariel)· was huge and blood passed in rt>lrograde fashion lhrough 1he left and middle colic aneries 10 lhe gas1ro-duodt>nal artet~· and rrmaining ccrliac branches. The abdominal aona below 1he inferior mesenleric anery was hypoplastic as were lhe iliac arterit>s. :\ sys1olic prc~surc gradit>nt of 110 mm.Hg existed between 1hc 1horacic and abdominal aorta and 1he major change in pres~ure occurred at the level of 1he renal aneries ( Fig. 3). No diff<'ren•·e he1wecn 1hr 1wn kidneys was found on split renal function 1es1s. An 1'11 -Hippuran scan demonslrated slighlly less uptake of radioae~ivi1y ovt>r the lefl kidnt>y. The pa1iem was placed on a I ,000 mg. sodium diet and antihypenensive drugs. During tht> subsequ<'nl six momhs he receiwd rcs<'rpine, chlorolhiazide, hydralazine and guane1hidine, bu1 the blood pressure was no1 consis1emly controlled, rising as high as 260/ 180 mm.Hg afler exertion

and falling lo 150/ 100 mm.Hg when slanding al res1. Wi1h lower blood pressures 1he pa1ien1 de\'eloped episodes of orthoslalic hypo1ension, parlicularly in 1he morning. The physical signs and the eleclrocardiographic evidence of lefl ventricular hypertrophy were nol altered by 1his course of treatmenl and it was felt thai in view of the age of the pa1icn1, and 1he difficulty in obtaining effeclive regula1ion of blood pressure, surgery should be performed. Opera1ion was performt>d on June 29, 1962 using an intrapleural, retroperitoneal approach through !he lefl side. The descending !boracic aorla was hypoplaslic from !he left subclavian artery dis1ally. h measured approximalely 1.5 em. in diame1er. Enlarged inlercoslal vr~st'ls were presem below 1he sixlh 10 lenth ribs. The aona narrowed sharply just above 1he level of the ccrliac axis. The ccrliac artel-y itself was small bu1 immediately 'expanded ·to a large hepatic and splenic artery. The aona, in 1he area in which the ccrliac artel)· arose, was

BP 130/80---+...

BP ZI0/110

Iaroe int.mommory a rower i ntercosto I arteries moderate hyperplasia

BP

hypoplos1ic

Ftot'RE

~:

£.'B.

in f. mesenteric o.

Drawing of the preo!M'rative anatomy.

FioURE

cedure.

5:

Drawing of the reconstructive pro-

520

BAIRD, LABROSSE AND EVANS

somewhat larger than that immediately distal. The superior mesenteric anery was present, but was completely thrombosed. The tissue in this area of the abdominal aona was exceedingly hard and fibrotic and difficult to dissect. As the aona in the region of the renal vessels was cleared of this fibrotic tissue, the amplitude of pulsation in the right renal vessel increased notably; when it was completely dissected free of fibrotic tissue, the stenotic area at the origin of the right renal vessel had disappeared. The left renal anery remained small despite removal of the perianerial fibrous tissue. The calcified mass below the right renal anery was an aneurysm arising from the aona immediately below the renal aneries and constricting the aortic lumen at this level. The inferior mesenteric anery was very large (I em. ). The aona continued distally with a diameter of approximately I em. The iliac vessels were very small. Pressures were 205 / 110 mm.Hg in the thoracic aona and 100/ 70 mm.Hg in the aorta at the level of the inferior mesenteric artery. The pressure in the left renal artery was identical to that in the distal ponion of the abdominal aona. The lesion. therefore, consistrd of a hypoplastic thoracic aona from the level of the subclavian anery distally, and a complete, or almost complete, coarctation above the level of the ccrliac anery with a second complete or almost complete coarctation distal to the ccrliac artery. The aorta from the second warctation to the renal aneries was severely hypoplastic, became moderately hypoplastic at the level of the renal aneries, and immediately distal to them was constricted again by the aneurysm. Thus, the abdominal aona was hypoplastic and contained three separate coarctations. The left renal artery was small. The right renal anrry had been narrowed by a perianerial fibrous constricting process. The superior mesenteric artery was occluded. The c~liac anery was small at its origin from the aona, but immediately enlarged. The inferior mesenteric artery was huge and was the major blood supply to the gastro-intestinal tract, liver and spleen (Fig. 3) . The aona betwt"en the renal aneries and the inferior mesenteric anery was excised. This area of the aona included the aneurysm, which was in communication with the aona through a small orificr and had a smooth rndothelial lined wall which was heavily calcified. The resected area of aorta was replaced with a ~-inch knitted Teflon graft. A second Teflon graft (diameter ~ inch) was then placed from the thoracic aona at the level of T9 to the previous Teflon graft. The anastomosis was end-to-side at both ends. On opening this graft, the aona and all its branches but the left renal anery were ~n to pulsate normally. The left renal anery remained pulseless. A third Teflon graft ( l4 inch in diameter) was

Dionta ol I~ Cbftt

then insened hetween the left renal artery and the thoraco-abdominal bypass graft. This produced exceiient pulsations in the left renal anery. At the completion of the procedure the patient's blood pressure was 130 / 80 and normal pulsations were present in all palpable abdominal and leg aneries (Fig. 4) . On histologic examination, the wail of the aona, in the area of the aneurysm, had normal layers but was surrounded by an increased zone of dense fibrous tissue. The wall of the aneurysm itself was composed mainly of fibrous tissue and there were no anerial elastic fibers present. Organized and calcified thrombus lined the interior of the aneurysm. In the sections of the aneurysm wail there was no evidence of a pre-existing inflammatory lesion. The patient's postoperative course was complicated with many minor crises. On the evening following surgery, a repeat laparotomy was necessary to evaluate a flank hematoma. Continuous oozing from many points was seen, but no large bleeding vessels were found. In the first postoperative week, he had episodes of bleeding from both tht" gastrointt"stinal tract and the urinary tract. A recurring left pleural effusion required thoracenteses on three occasions. Persistent fever, anemia and leukocytosis associated with abdominal pain and right lower quadrant tenderness raised diagnostic considerations of appendicitis, retroperitoneal hemorrhage or infection, or aneritis of vessels previously protected from hypertension by the coarctation. It was considered possible that the crampy abdominal pain, nausea and episodic vomiting which followed eating were related to removal of c~liac and superior mesenteric ganglia during surgical dissection. At operation, both adrenal veins were ligated, but postoperative evaluation of adrenocortical function revealed no impairment. The patient returned to normal activity six weeks after surgery. At that time, blood pressure in the arms measured 190/ 100 mm.Hg and in the legs 170/ 90 mm.Hg. The femoral pulses were readily palpable and faint pulsations were detected in the dorsalis pedis aneries. Hean size was unchanged and the systolic murmur and atrial gallop rhythm were present. Evaluation six months and one year after surgery revealed persistent hypenension of mild to moderate degree with values in the upper limbs ranging from 140/70 to 200/110. Blood pressure in the lower limbs was approximately 140/ 80. The pulsations in the lower extremities and the cardiac findings remained as noted six weeks after operation. The electrocardiogram continued to show evidence of left ventricular hypenrophy. An aonogram showed excellent function of the bypass graft with filling of both renal aneries (Fig. 5) .

Volume 48, No. Novombor 19M

~

COARCTATION OF THE ABDO:O.U:-:AL AORTA

Eight months after operation, th!' patient not-

ed enlargement of a pigmented nevus on the right calf. This was widely resected and histologic !'xamination r!"ve;~led a malignam nwlanoma without extension to the margin of the specimen. Shortly after, a large, firm node was detected in the groin, whkh was resected and demonstrated secondary deposits. One year after rt'constructive vascular surge!)·, the patient had e\·idence of widespread m<'tastases. DISCUSSION

Nature of the Lesion: Whether coarctation of the abdominal aorta is congenital or acquired is controversial. l\fayock' proposed that it arose from unequal fusion of the two embryonic dorsal aortz (omphalomesenteric arteries) with subsequent obliteration of one of them. Syphilis, rheumatic fever, non-rheumatic inflammation, and neoplasia have been proposed by those who fa,·or an acquired etiology: and the recent reports of Inada• suggest a possible a-;sociation with "pulseless diseao;;e." Like "pulseless di~easc'' and renal fibromuscular hyperplasia, this lesion is more common in women, wherea~ coarctation of the aortic isthmus is more common in men.•·• The dense fibrotic tissue surrounding the area of coarctation is

521

frequently interpreted as evidence of an acquired etiology. Pathologic evidence of neurofibromatosis (Von Recklinghausen's diseao;;e) was found both in tissue removed from the site of coarctation and elsewhere in two patients with this disorder.'·' Since there is no conformity to the pathologic picture, it seems rea<;onable to speculate that cases with long segments of hypoplasia of the abdominal aorta are congenital in origin, whereas cases with more localized lesions rna,· be caused by a non-specific aortitis characterized by the production of dense periaortic fibrous tis.-;ue. Pyoraia,' using the classification of D'Abreu,' reviewed 27 cases of abdominal coarctation. He noted that 17 were segmenta~· ( 63 per cent) and ten invoh·ed a considerable length of hypoplastic aorta ( 37 per cent). Both segmenta~· and hypoplastic varieties could be suprarenal, at the level of the renal arteries, or infrarenal. In some instances, the hypoplasia began in the lower thoracic aorta or continued distally beyond the iliac ves.o;;els; any or all of the branches of the abdominal aorta could be involved by the proces.'i. With occlusion or narrowing of the ccdiac and superior mes-

FIGURE 6: Angiogram six months after surgery showing patent grafts from thoracic to abdominal aorta and to left renal artery.

522

BAIRD, LABROSSE AND EVANS

enteric arteries, as in the present case and that reported by Bayliss," the major blood supply to the intestines, liver and spleen was derived from the inferior mesenteric artery. The renal arteries may be normal, hypoplastic, narrowed at the origin, or occluded by thrombosis. The present example of coarctation of the abdominal aorta appears to represent a combination of two areas of segmental coarctation, one above, and one below the ca:liac axis. A third area of narrowing was present at the site of the calcified aneurysm. .-\ calcified aneurysm distal to the coarctation was. also noted in the case of Bayliss and aneurysms of the right renal artery were reported in the cases of Glenn• and Senning.' The mechanism of aneurysm formation distal to coarctation of the aortic isthmus has been studied by Skandalakis," and Dun hill," and it is reasonable to speculate that any congenital weakness of the aortic wall would be aggravated by the turbulence, cavitation and increased lateral pressure beyond the coarctation. The possibilitv of superimposed mycotic infection, as noted by Kieffer'" in 19 cases of thoracic coarctation, was favored by the youth of the patient, the localized nature of the aneurysmal bulge, and the calcification in the wall, but there was no history to indicate infection and no pathologic evidence of a specific inflammatory process. Clinical Features : The symptoms of coarctation of the abdominal aorta vary with the location and severity of the lesion. When the coarctation is above the renal arteries, the symptoms resemble those of classic coarctation and are related chiefly to hypertension. Leg weakness and intermittent claudication are rare. \\'hen coarctation involves the renal vessels, the hypertension may be particularlv severe, and heart failure and uremia mav ~ccur." When the coarctation is infrarenai, hypertension is usually mild, and intermittent claudication of the buttock or calf is usually the presenting symptom." The physical signs of hypertension in the upper extremities, and diminished or absent pulsa-

Diseases of the Chest

tions in the legs permit the diagnosis of coarctation, but the abdominal site of narrowing is indicated by the presence of a thrill and murmur in the epigastrium, and by the prominent collateral arterial circulation over the lower portion of the chest. On radiologic examination, the aortic knob appears normal, and notching is seen on the lower rather than the upper ribs. The precise location of the coarctation and the extent of involvement of other vessels can be established with aortography. Renal function studies may demonstrate impaired function not suspected from the aortagrams. Senning' proposed that the natural historv of this disorder was similar to that of co~ctation at the aortic asthmus. He noted that ten of 32 patients with this disorder died before the age of 34. It might be expected that lesions above or involving the renal arteries would constitute a more serious risk. Surgical Treatment: Prior to the era of reconstructive vascular surgery, the treatment of this type of coarctation was either impossible or completely unsatisfactory. Several attempts at sympathectomy and nephrectomy are recorded. • The first case operated upon with reconstructive vascular technique was that of Beattie'• in I951 . Since then, there have been 20 reported ca<;es (Table I) . From perusal of the case reports, several lessons may be learned: ( I ) exact knowledge of the site and extent of the coarctation must be obtained by angiography prior to surgery; ( 2) renal function tests may be necessary to demonstrate if renal blood flow or function is impaired; ( 3) dense fibrous tissue surrounding the aorta, when removed, often leads to marked enlargement of the aorta and its branches; ( 4) when the renal arteries are not involved, either bypass grafting, patch grafting, or local excision of the coarcted area are equally successful ; ( 5) involvement of the renal arteries makes surgery more difficult and the prognosis less favorable; ( 6) and extra peritoneal approach through the left side has

TABLE I-REPORTED CAllES OF RECONSTRUCTIVE SURGERY FOR COARCTATION OF THE ABDOMINAL AORTA Renals Repair Aneurysm Location Fibrosis Type* Sex Age Year Involved Reported

Author

s

1 Beattie" et al. 2 Albanese" et al. 3 Glenn• et al.

1951 1952 1952

19 12 19

F F F

Above renals Below renals Ahovr r~nals

H

4 Guastavino 11 tt al.

1956

II

F

Ahm·r renals

s

1958 1959 1959 1959

II

40 58 12

F M F F

9 Milloy4 tt al.

1959

18

M

Above renals Above renals B~low renals Above and at renals Above, at & below rcnals

I 0 Senning" et al.

1960

25

M

5 6 7 8

Gerbasi" D' Abreu• D'Abreu1 Hanson10

et et tt tt

al. al. al. al.

II Senning" et al. 12 Stokea11 It al.

13 Morria et al 14 Morria 11 et al. 15 Morris 11 et al. 11

1960 1960

1960 1960 1960

25 12

12 20 16

M F

F F F

s s

No No Yes-Neurofibromatosis Yes

Yes- R R~nal

No

H

Yes Yes Nn Yes

No No No No

H

No

No

Above and at renals Below renals Above and below rcnala

H

Yes-Neurofibromatosis No No

rena1s renala and renals

s

Above Above Above below

H

s

H H

H H

Yea Yes No

16 Morria 11 tt al.

1960

I

M

Above and at renals

H

No

17 Morria 11 tt al. 18 I ndana1 et al. 19 Bjork11 tt al.

1960 1962 1964

35 43 18

F M M

Above renala Above reoals Above, at & below renals

H H

s

No No No

20 Baird11 et al.

1964

19

M

Above, at & below renals

H

Yea

*S=segmental, H=hypoplastic.

No

Yea- R Renal No No

No No No No

Bypass Grah NoResection and Grah Splenic Art. to Thoracic Aorta Resection and Anastomosis Bypass Grah Bypass Graft Bypass Grah Posterior patch graft Bypass and aubsequent leh nephrecto my Posterior patch graft Bypass grah Bypass grah with aide arm to renals subsequent right nephrectomy. Bypass graft Enderectomy Bypass grah Bypass graft

Bypass graft Bypass graft Bypa.ss graft with aidearme to right renal, subsequent right nephrectomy Bypass graft with Yea (aortic} aide arm to renal a No No No

Z<

0 0

R~ault

No Yes No

Good Died- Anuria Good

No

Good

No No No Yes

Good Good Good Good

Yes

Good

Yes

Good

No Yes

Good Good

No No

Yea

Good Good DiedHeart Failure Died -·

No No Yea

Good Good Good

Yea

Good

Y~•

H L __.. ~z ~0

(l

~

"' >

(l

-i

-i

0 z

..,0 -i

::t:

til

> til

8f:(

z

> r

~

"' > -i

H~art Failur~

<.1\ ~

w

BAIRD, LABROSSE AND EVANS

many advantages in this type of surgery since it allows the entire abdominal aorta to be visualized and gives adequate exposure for angioplastic procedures on both renal arteries. Postoperative complications may arise from adrenal insufficiency due to ligation of adrenal veins, mesenteric vasculitis, or gastr~intestinal disturbances due to denervation of the small bowel."·" Hence, the convalescent period following operation may be prolonged and troublesome.

6

7

8

9 10

SUMMARY

Successful surgical correction of abdominal aortic coarctation is reported . The structural abnormalities present included three sites of narrowing of the abdominal aorta, hypoplasia of the thoracic and abdominal aorta, thrombosis of the superior mesenteric artery, narrowing of the right renal artery, and a calcified aneurysm distal to the coarctation. The patient presented with severe hypertension which was not effectively controlled by medical measures. Following reconstructive vascular surgery, the blood pressure in the upper extremities was reduced, and improved arterial pulsations were present in the legs. The anatomic and clinical features of patients with coarctation of the abdominal aorta are briefly reviewed and problems related to surgical treatment discussed. ACKNOWLEDGEMENTS : The authors express their thanks to Dr. George Tucker, and Dr. W. B. Spaulding for referring the patient for investigation and treatment, to Dn. E. R . Yendt and R. Volpe for the renal function studies.

2

3

4 5

REFERENCES MAYOCK, W. D'A. : "Congenital Stenosis of the Abdominal Aorta," Am. Heart ]., 13 :633, 1937. BAHNSON, H . T ., CooLEY R . N . AND SLOA N, R. D .: "Coarctation of the Aorta at Unusual Sites: A Report of 2 Cases with Angiographic and Operative Fndings," Am. Heart ]., 38 : 905, 1949. INADA, K ., SHnuzu, H . AND YoKOYAMA, T . : "Pulseleu Disease and Atypical Coarctation of the Aorta with Special Reference to their Genesis," Surgery , 52 : 443 , 1962. MlLLOY, F. AND FELL, E. H. : "Elongate Coarctation of Aorta," Arch Surg., 78 : 759, 1959. GLENN, F., KEEFER. E. B., SPEER, D . s. AND DoTTER, C . T .: "Coarctation of the Lower

II

12

13

14 15

16 17 18

19

20

21

22 23

Distasts of the Chest

Thoracic and Abdominal Aorta Immediately Proximal to the Ca:liac Axis, " Surg., Gynu. and Obstet., 94 :561, 1952. SENSING, A. AND JoHANSSON, L. : "Coarctation of the Abdominal Aorta," ]. Thor. and Cardiovas. S11rg., 40 :517, 1960. PYORAIA, K ., HEINONEN, 0 ., KosELKO, P. AND HEIKEL, P. E.: "Coarctation of the Abdominal Aorta: Review of 27 Cases," Am. ]. Cardial., 6:650, 1960. D'ABREU , A. L. D., RoB, C. G. AND VALLMAR, I. F.: " Die Coarctatio Aorta! Abdominalis," Arch. Klin . Chir. , 290 :521, 1959. BAYLiss , G . J.: "Collateral Circulation Following an Obstruction of the Abdominal Aorta," Anal. Record. 75 : 405, 1939. SKANDALAKIS, J. E. , EDWAJtDS, B. F., GRAY , s. W., HOPKINS, w. A. AND DAVIS, B. M. : "Coarctation of the Aorta Complicated by the Formation of an Aneurysm," Surgery , 52:444, 1962. DuNHILL, M. S.: "Histology of the Aorta in Coarctation," ]. Path . and Bact ., 78 : 203, 1959. KIEFFER. S. A. LINDE , L. M ., KEGEL , s. M. AND LATIA, H. J. : "Mycotic Aneurysm Distal to Coarctation of the Aorta," f . Thor. and Cardiot·as. Surg., 42:507, 1961. MoRRis , G . C. DEBAKEY, M. E. , CooLEY, D . A. AND CRAWFORD, E. S.: "Subisthmic Aortic Stenosis and Occlusive Disease," Arch. Surg., 80 : 87 , 1960. INMON, T . W . AND PoLLOCK B. E.: "Coarctation of the Abdominal Aorta : Review of the Literature." Am. Heart] ., 52 : 314, 1956. BEATTIE, E. J. , CooKE, F . N .• PAuL, J. S. Al'."D OR BISON. J. A. : "Coarctation of the Aorta at the Level of the Diaphragm, Treated Succeufully with a Preserved Human Blood Vessel Graft," ]. Thor. Surg., 21 : 506, 1951. ALBANESE, A. R. AXD BAlLA, M . R .: "Coractation Congenita de Ia Aorta Abdominal," Bol. Acad. Argent., Circulation , 37 : 211 , 1953. AsHBY, W . B. : "Autotransplantation of the Small Intestines. The Effect of Denervation," Surgery. 52 : 151 , 1962. GuASTAVI NO, G . N . Al"D REcu, L. : "Coarctationes Aortices Ubicados por debajo del Sitio Habitue! ( Un Cas de Doble Coarctation. Resection y Homoinjecto) ," Ret•. Assoc. Med Argent ., 70:347, 1956. GERBASI. F. S., KIBLER, R . S. AND MARGILETH , A. M .: "Coarctation of the Abdominal Aorta. A Case Successfully Treated Surgically," ]. Pediatrics," 52 : 191, 1958. HANSON, J. . IKKOs , D ., JoHANssoN, L., RuDHE . U. AND SENSING, A.: "Coarctation of the Abdominal Aorta : Case Report and Description of Successful Surgical Treatment," Acta Chirurg. Scand.. 245 : 315, 1959. STOKES , J. M ., WOHLTMANN , H . Al'o-o CARLSON , E. : "Coarctation of the Abdominal Aorta and Renal Artery Stenosis Corrected by Surgical Treatment: The Importance of Individual Renal Function Tests in Selection and Proper Management," Ann. Surg., 152 :856, 1960. BJORK, V . 0 . AND ITosTI , F .: "Coarctation of Abdominal Aorta with Right Renal Artery Stenosis," Ann. Surg. , 168 :54, 1964. BAIRD, R . J., EvANs. J. R. AND LABROSSE , C . J.: "Coarctation of the Abdominal Aorta," Arch. Surg., 89:466, 1964.

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