Congenital Aneurysm of The Left Ventricle

Julio C. Davila, M.D., Francisco Enriquez, M.D., Stephen Bergoglio, M.D., Gerard0 Voci, M.D., and C. Robert E. Wells, M.D.

ongenital aneurysms of the left ventricle are rare. Sporadic cases have been reported since 1834, when O'Bryan [l 11 described a C pathological specimen of a diverticulum of the left ventricle

which passed through the diaphragm into the anterior abdominal wall in a 3-month-old infant. Skapinker [15] in 1951 and Potts et al. [14] in 1953 reviewed the world literature and presented their experiences. Surgical excision by closed techniques has been reported in seven cases. See Table 1 which also lists all published cases.

The purpose of this article is to present the first case in which resection of a saccular aneurysm was accomplished using cardiopulmo- nary bypass, to bring up to date the tabulation of reported cases, and, finally, to suggest that these lesions are of two distinct types. Five cases of ectopia cordis reported by Cantrell et al . [4], Crittenden et al. [5a], and Mulder et al. [6] have been excluded from our study, because aneurysm of the left ventricle is only a small part of a syndrome which includes multiple, noncardiac, congenital abnormalities.

CASE R E P O R T

Patient T. F. was first referred to St. Christopher's Hospital at the age of 6 months for evaluation of her cardiac status. On the second day of her life, both her father and the pediatrician had noted rapid respiration. X-rays were taken and these revealed marked cardiac enlargement. The family history was negative. After that episode, the patient remained asymptomatic.

At the time of subsequent admission for special studies, the physical exami- nation revealed an adequately nourished and developed 9-month-old girl, weigh- ing 16 pounds 8 ounces. Temperature was 99"F., pulse 152, respirations 52. Blood pressure readings were: right arm, 110/85; left arm, 115/75; right leg, 105; and left leg 110 mm. Hg by the flush method. Good femoral pulses were present. There was no cyanosis or clubbing. There was no thrill. There was a grade 2 short,

From the Thoracic and Cardiac Surgical Section of Temple University Medical Center and the Department of Pediatric Cardiology of St. Christopher's Hospital for Children, Phila- delphia, Pa.

Received for publication Mar. 24, 1965.

VOL. 1, NO. 6, NOV., 1965 697

DAVILA ET A L .

A B FIG. 1. ( A ) Preoperatiue chest x - m y . There is marked cardiac enlargement of the left ventricle. The intrapulnionary uasculature is normal in appearance. (B) Post- operative (18 months) chest x - m y reuealed the heart to be smaller and more normal in contour.

rough, grating, apical systolic murmur. Diastole was clear, and the second sound at the pulmonic area was normal. The liver edge was 1 cm. below the right costal margin. The rest of the physical examination was within normal limits.

X-ray (Fig. 1A) revealed 3+ to 4+ cardiac enlargement of the left ventricular type with a peculiar bulbous form. T h e pulmonary vasculature appeared normal.

ECG (Fig. 2) revealed marked left ventricular hypertrophy with strain. There was a reversal of the T waves across the precordium and inverted T waves in leads I, 11, antl AVF.

At cardiac catheterization, the O2 study failed to reveal intracarcliac shunting of blood. Arterial 0, saturation was within normal limits.

Retrograde catheterization of the left ventricle via the aorta was carried out for cineangiography (Fig. 3A, H , C). The left ventricle seemed to be partitioned into a normal-sized proximal contractile portion antl a relatively noncontractile distal portion, almost as large, which filled secondarily from a small stream from the proximal portion. Sluggish contractility raised the possibility of fibroelastosis. An injection in the root of the aorta revealed normal origin, caliber, and coiirse of the coronary arteries. Pressures within the piilmonary circiilation were at the upper limits of normal. The pulmonary artery wedge pressure was slightly elevated, as was the left ventricular end-diastolic pressure.

When the patient was 14 months old, surgery was performed. The patient was placed in the dorsal decubitus position and the chest was entered through a mitl- line, sternum-splitting incision. The pericardium was opened in the midline and the aneurysm was visualized (Fig. 1A). I t was located on the lateral wall of the left ventricle and measured about 6 cm. in diameter, 2.5 cm. in height; it had a broad base. The wall was very thin and even transparent in several areas. The patient was placed on total bypass using the superior and inferior venae cavae for venous return and the right external iliac artery for the arterial line. The aneurysm was opened, revealing two chambers, one measuring 2.4 cm. and the other 1.5 cm. in diameter (Fig. 4B). There was a communication between the larger chamber and the left ventricle. The smaller chamber communicated with the larger one through a 1.0 cm. hole in the septum between the two. The com- munication with the left ventricle was 1 cm. in diameter. The inner surface of the aneurysm was white and glistening, suggesting the possibility of endocardial fibroelastosis. T h e endocardial surface of the ventricular cavity could be partially

698 1 H E ANNALS 01; lHORACI<; SURGERY

Congetiital b'entrirwlar Aneurysms

FIG. 2 . (Above) Preoperative ECG. Marked left ventricular hypertrophy with strain. There is reversal of the T waves across the precordium and in- verted T waves in leads I , 11, and AVF.

(Left) Postoperative (18 months) ECG. Less left ventricular hypertrophy, but the strain is persistent.

VOL. I , NO. 6, NOV., 1965 Ggg

DAVILA E T AL.

FIG. 3. T h e angiocardiogram rmealed progressiue filling (left to right) of n large aneurysm-like structure arising from the left ventrick. T h e nnrirrysm is noncontractile; the main body of the ventricle does not contract as vigorously ns cxpected. Both coronaries originate from the aorta and appear to ha-oc a norrnnl distribution. Blood gas studies show n o evidence of shun!s.

visualized through the small opening, and it appeared to be normal. The opened aneurysm was resected at its base, and the myocardial defect was closed with five heavy silk mattress sutures and reinforced with a continuous row (Fig. 4C). The bypass was discontinued, and the heart beat was of good quality. The pericardium was closed with a few interrupted stitches, a chest tube was inserted into the pericardial cavity, and the chest was closed.

The postoperative course was uneventful as far as her cardiac condition was concerned. It was complicated, however, by a bout of pneumonia which subsided promptly with antibiotic therapy. Digitalization was started on the first post- operative clay, and the patient was discharged on a maintenance dosage. At this writing, she is 20 months postoperative, in excellent condition, and off medica- tions.

The pathological specimen consisted of a bowl-shaped structure 4.0 cm. in its greatest diameter and 2.0 cm. in height. The convex or external surface was smooth and exhibited scattered petechiae. The concave aspect was incompletely divided into a smaller and a larger compartment, lined by thick, opaque endo- cardium. At the site of resection the wall was composed of thin myocardium which varied from 0.2 cm. to 0.7 cm. in thickness. Near the vertex, however, there were two areas where the wall was extremely attenuated, being less than 0.1 cm. in thickness.

Sections were stained with hematoxylin and eosin, Masson’s trichrome, and Verhoeff’s elastic tissue stain. The endocardium consisted of a thick layer of elastic tissue fibers and somewhat smaller amounts of collagen. The elastic was more concentrated toward the luminal aspect of the specimen. Peripherally, bundles of collagen devoid of elastic tissue extended into the myocardium. Coarse trabeculae of collagen also extended from the epicardium into the subjacent myocardium. The thin, apical portions of the specimen consisted almost entirely of fibroelastic tissue with only islands and isolated strands of myocardial fibers; here the tissue was predominantly collagenous, with scant elastic tissue fibers being largely con- fined to the luminal aspect. The arrangement of elastic tissue fibers was somewhat different from that usually encountered in endocardial sclerosis, in which the fibers tend to be located predominantly toward the myocardium rather than luminally as in the present specimen. There was no inflammatory reaction.

T h e lesion is probably best interpreted as simple failure of development of myocardial fibers in a localiied area of the heart, with endocardial sc1erosi.s secondary to the muscular defect.

700 THE ANNALS OF THORACIC SURGERY

A

B

C

FIG. 4. Drawings of the operatiue steps, and photographs of pathological speci- mens. (A) Af ter opening the pericardizim. Pathological specimen: The conilex or serosal surface was smooth and contained sctlttered petechiae. ( B ) T h e aneurysm open, revealing 2 chambers, one measuring 2.4 cm. and t h e other 1.5 cm. i n diameter. Pathological specimen: T h e concaue surface, which is incompletely divided into a smaller and larger compar tment , is lined by thick, opaque endocardium. (C) T h e opened aneurysm was resected at its base and the myocardial defect was closed wi th five heavy silk mattress sutures and reinforced w i th a cont inuous suture. Pathological specimen: T h e thinned-out areas are shown by transillumina- tion.

VOI.. I , NO. 6, NOV., 1965 7 0 1

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regu

lar

stra

nds

of

fibr

ous

tissu

e sc

at-

tere

d th

roug

h th

e m

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lar

budl

es

and

som

ewha

t th

ick-

en

ed f

ibro

us e

ndoc

ardi

a1 la

yer

wit

h no

rmal

pr

opor

tion

of

el

astic

tis

sue

Prop

osed

C

lass

ific

atio

n of

A

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ysm

Fa

tea

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ertic

uloi

d;

Die

d mu

1 tip

le

hear

t de

fect

s

Div

ertic

uloi

d

Div

ertic

uloi

d

Clo

sed-

hear

t su

rger

y;

base

cla

mpe

d,

tran

- se

cted

, an

d m

argi

ns

over

sew

n

Clo

sed-

hear

t su

rger

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base

cl

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d, t

ran-

se

cted

, an

d m

argi

ns

over

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n

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se o

f D

eath

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rt f

ailu

re

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fol

low

-up

NO

fol

low

-up

TA

BL

E 1

(C

onti

nued

) Prop

osed

C

lass

ific

atio

n R

epor

ter

Yea

r A

ge

Sex

Ana

tom

ical

Det

ail

of A

neur

ysm

Fa

tea

Cau

se o

f D

eath

Paro

nett

o [1

21

1963

8

mo.

F

Lar

ge

circ

umsc

ribe

d an

eury

sm

Div

ertic

uloi

d D

ied

of

the

left

ven

tric

le a

ssoc

iate

d w

ith

endo

card

ial

fibr

oela

stos

is

conf

ined

to

th

e no

nane

urys

- m

a1 p

art

of

the

vent

ricl

e

Dav

ila e

t al

. [p

rese

nt

repo

rt1

Hea

rt f

ailu

re

1964

9

mo.

F

Sacc

ular

an

eury

sm

mea

suri

ng

Sacc

ular

O

pen-

hear

t su

rger

y;

Liv

ing

and

wel

l, ne

arly

6

X

2.5

cm.

bilo

cula

ted;

con

- tr

anse

cted

at

its

neck

tw

o ye

ars

post

oper

ativ

e si

sted

of

epic

ardi

um,

myo

car-

an

d th

e m

argi

ns

dium

, an

d th

icke

ned

opaq

ue

over

sew

n w

hite

end

ocar

dium

; ev

iden

ce

of

endo

card

ial

scle

rosi

s th

roug

hout

al

l la

yers

'Pat

ient

s in

whi

ch n

o re

fere

nce

to s

urge

ry i

s m

ade

wer

e no

t op

erat

ed o

n. W

here

que

stio

n m

ark

appe

ars,

no

info

rmat

ion

is av

aila

ble.

DAVILA ET AZ..

TYPES OF ANEURYSMS

All reported cases are listed in Table 1. T h e anomalies have been labeled congenital diverticulum by some and congenital aneurysm by others. Perusal of these cases reveals that these lesions are aneurysms of two distinct types. T h e term aneurysm, derived from the Greek aneurynein, to dilate, seems more appropriate for both types than diverticulum, from the Latin devertere, to turn aside.

DIVERTICULOID ANEURYSM

Diverticuloid aneurysms are found in the majority of the cases; they arise in the region of the ventricular apex. In most instances the “diverticulum” then descends through a defect in the diaphragm to present as a pulsatile mass in the epigastrium or is contained in an umbilical hernia. T h e deverticuloid aneurysm is commonly associated with other anomalies. T h e wall consists of a thinned-out portion of normal-appearing ventricular myocardium lined by endocardium and covered by epicardium. T h e sac may be completely or partially enclosed by pericardium. --

Embryologically the ventral pCdtion of the septum transversum- gives rise to the diaphragmatic, ventral portion of the pericardium, the leaf of the diaphragm, and, by fibrous proliferation, the ventral portion of the abdominal wall [3]. Thus it would appear that the congenital “diverticulum” is closely associated with defective development of the septum transversum. T h e left ventricular cavity is formed from the greatest convexity of the cardiac loop. As the cardiac loop is being formed this portion comes into close proximity with the ventral portion of the septum transversum. At this point the epimyocardiuin of the loop fuses with the mesenchyme of the septum transversum, and, as the latter descends, the apical myocardium is pulled ventrally and caudally.

Normally the myocardium is thinnest at the apex in the region of the whorl formed by the spiraling muscle fibers. It is probable that posi- tion as well as traction contributes to formation of these anomalies.

SACCULAR ANEURYSM

Saccular aneurysm is not associated with anomalies of the dia- phragm or of the abdominal wall and has been discovered at necropsy in both adult [2, 71 and child [17]. These appear to be related to defects in development of the ventricular wall in other than the apical region. They are usually asymptomatic and discovered as an accidental roent- genological finding or at necropsy. T h e wall consists of endocardium, scanty or absent myocardium, and epicardium. T h e sac is contained within the pericardium and may be uni- or multiloculated, and its wall is often translucent as in the case presented above.

708 1 H E ANNALS OF THORACIC SURGERY

Congenital Ventricular Aneurysms

These may be the result of abnormal myocardial sinusoids as suggested by Lovitt et al . [7] or simply of excessively thin myocardium in the region of a deep groove between trabeculae carneae. Pulsion would appear to be a significant factor, whereas traction does not play a role. It is not clear whether endocardia1 fibroelastosis plays a primary part or is a secondary or incidental factor in either type of anomaly.

SUMMARY

T h e first successful resection of a congenital saccular aneurysm of the left ventricle with the use of extracorporeal circulation has been reported. An attempt has been made to classify the 27 reported cases into two groups-diverticuloid and saccular aneurysms-in accordance with their embryological, anatomical, and pathological characteristics.

ACKNO IVLEDGMENTS

The authors wish to acknowledge the participation of Dr. J. Kirkpatrick in the radiological study, and Dr. J. Arey in the pathological study of the specimen of the case presented. Drs. A. Caruso and C. Fink contributed to this presenta- tion by their assistance in the operative management of the case presented and in reviewing the literature.

REFERENCES

1. Bailey, C. P. 2. Bertrantl, C. A., and Cooley, R. N. Congenital aneurysm of left ventricle:

Case report. Ann. Intern. Med. 43:426, 1955. 3. Bremer, J . L. Transposition of aorta and pulmonary artery: Embryologic

study of its cause. Arch. Path. 31:1016, 1942. 4. Cantrell, J. R., Haller, J. A., and Ravitch, M. M. A syndrome featuring

defects of the heart, sternum, diaphragm, pericardiiim and heart. Surg. Gynec. Obstrt. 107:602, 1958.

A syndrome featuring defects of the heart, sternum, diaphragm and anterior abdominal wall. Circiilation 20:396, 1959.

Surgery of the Heart. Philadelphia: Lea 8c Febiger, 1955.

5a. Crittenden, I. H., Atlanis, F. A., and Mulder, D. G.

5b. Formijne, P. 6. Galindo, L., Arean, V. M., Stevenson, S. D., and Rivera, C. Congenital

diverticulum of the heart. Amer. J. Clin. Path. 27:84, 1957. 7. Lovitt, W. V., Jr., and Lutz, S., Jr. Embryological aneurysm of the myo-

cardial vessels. Arch. Path. 57: 163, 1954. 8. Lowe, J. B., Williams, J. D. P., Robb, D., and Cole, D. Congenital diverticu-

lum of left ventricle. Brit. Heart J. 21: 101, 1959. 9. Mulcler, D. G., Crittenden, I. H., and Adams, F. A. Complete repair of a

syndrome of congenital defects involving the abdominal wall, sternum, diaphragm, pericardium and heart: Excision of left ventricular diverticulum. A n n . Siirg. 151:113, 1960.

10. Mustard, W. T., Duckworth, J. W. A., Rowe, R. D., and Dolan, F. G. Con- genital diverticulum of the left ventricle of the heart. Canad. J . Stirg. 50: 149, 1958.

11. O’Bryan in T. B. Peacock, (Ed.): On Malformations of the Human Heart (2nd ed.). London: J. Churchill and Sons, 1866.

Aangeboren hartebreken. Nederl. T . Geneesk 94:2704, 1950.

VOL. 1 , NO. 6, NOV., 1965 tog

DAVILA ET AL.

12. Paronetto, F., and Strauss, L. Aneurysm of the left ventricle due to con- genital muscle defect in an infant. Amer. J. Cardiol. 12:5, 1963.

13. Parsons, C. Ventricular extension into the abdominal wall. Brit. Heart J. 19:34, 1957.

14. Potts, W. J., DeBoer, A., and Johnson, F. R. Congenital diverticulum of the left ventricle. Surgery 33:301, 1953.

15. Skapinker, S. Diverticulum of left ventricle of the heart. Arch. Surg. 63:629, 1951.

16. Snellen, H. A., Dankmeijer, J., Briums, C., and Collister, R. M. Saccular elongation of the left ventricle into the abdominal wall with persistence of the anterior mesocardium and ventricular septa1 defect. Cardiologia 21 :562, 1952.

Cardiac aneurysm in a child seven years old. Amer. J. Dis. Child. 75:92, 1948.

17. Vivas-Salas, E.

The Editor and members of the Editorial Board are grateful for the assistance given in the review of certain manuscripts during the past year by the following:

BRUCE ARMSTRONG, M.D., Los Angeles, Calif. DAVID L. DEAN, M.D., Sun Fernando, Calif. JOHN H. EDMONDS, JR., M.D., Augusta, Ga. DONALD R. KAHN, M.D., Ann Arbor, Mich. ROBERT I. KATZ, M.D., Sun Fernando, Calif .

AVERILL A. LIEBOW, M.D., New Haven, Conn. EDWARD E. MASON, M.D., Iowa Ci t y , Iowa DONALD L. PAULSO", M.D., Dallas, Tex.

PAUL C. SAMSON, M.D., Oakland, Calif. GERALD WHIPPLE, M.D., Boston, Mass.

THOMAS YEH, M.D., Augusta, Ga.

710 THE ANNALS OF THORACIC SURGERY