REPAIR
OF
VENTRICULAR
SEPTAL
DEFECT
IN INFANCY
961
John W. Kirklin, M.D., and James W. DuShane, M.D.
Sections of Surgery (J.K.) and Pediatrics (J.D.), Mayo Clinic and Mayo Foundation
E
ABLY in the experience with openintra-cardiac surgery at the Mayo Clinic the
hospital mortality was high following
surgi-cal treatment of ventricular septal defect in
infants. In the last 2 years the mortality has
been markedly reduced. Therefore, it is at
present the policy in this institution to
operate upon sick, small babies with yen-tricular septal defect when it is thought that
they will fail to thrive or not survive until
the age of 3 to 4 years.
This paper presents the details of this
cx-perience. Factors important in securing high survival rates are emphasized.
MATERIAL
All 65 infants, 2 years of age or less,
operated upon by one of us for repair of
ventricular septal defect prior to October
1, 1960, are included in this study. Those
patients operated upon between April 1,
1955, and April 1, 1960, are also described
in less detail in a previous paper1 on the
surgical treatment of ventricular septal
de-feet in general during that period.
The patients operated upon constitute
ap-proximately 20% of all infants with
ventricu-tar septal defect seen at the Mayo Clinic
during this period. Operation in infancy was
considered indicated only when the infant
was in intractable or recurrent congestive
heart failure or when it was thought that
the baby would show severe failure of
growth. A few of the infants in the second
year of life were operated upon at this early
age because of the severity of their
pul-monary hypertension and the fear that
severe elevation of pulmonary vascular
re-sistance might otherwise develop.
Nearly all infants 1 year of age or less
were critically ill, with either intractable
or oft-repeated congestive heart failure
(Fig. 1). The degree of pulmonary
hyper-ADDRESS: Mayo Clinic, Rochester, Minnesota.
tension is indicated in Table I. Patients were
categorized as having mild pulmonary
hypertension when pulmonary-artery
sys-tolic pressure was 45% or less of
systemic-artery systolic pressure, moderate
pul-monary hypertension when it was between
45% and 75% of systemic-artery pressure, and
severe pulmonary hypertension when it was
75% or more of systemic-artery pressure
(Fig. 2). With one exception the patients
with mild pulmonary hypertension were
nearly 2 years of age and were operated
upon because of the cardiomegaly that was
present in spite of the mildness of the
dc-vation of pressure in the pulmonary artery.
METHODS AND SURGICAL TECHNIQUE
The technique employed in these infants
was in all ways similar to that used for older
patients and has recenfly been described in
detail.1 A Gibbon-Mayo pump-oxygenator
of the stationary vertical-film
type
wasem-ployed. The rate of blood flow was about
2.4
lit/min/m2. For the most part,tempera-ture was maintained at 37#{176}Cby the use of a
Brown-Emmons heat exchanger.2 In a few
cases hypothermic perfusions were
em-ployed. In the last 2 years halothane
(
Fluothane) has been used as the anestheticagent.
A
median sternotomy incision hasTABLE I
DISTRIBUTION OF PATIENTS BY AGE AND DEGREE OF PULMONARY HYPERTENSION
Age
(tao)
Pulmonary-Artery
Hypertension Total Patients Mild MOderate Severe
-1
18-4
1 10 S
6* 7 18
84 81
aOne patient had pulmonic stenosis and severe right
ventricular systolic hypertension.
FIG. 2. Roentgenogram of 1 1-month-old infant with in-tractable heart failure and severe pulmonary hypertension.
This child survived operation and remained well.
E?IG. 1. Preoperative roentgenogram of 6-month-old infant operated upon in 1958. In addition to striking cardiac
en-largement, there are partial atelectasis of the left lung and pneumonitis in the right upper lobe. This patient died 12 (lays after operation because of continuing bilateral
pneumonitis.
been uniformly employed since October,
1958. Cardiac asystole has been regularly
used since August, 1956, and for the last 2
years this has been induced by simple ischemia.
Although in the early years a number of
techniques with and without a prosthesis were employed for repair of ventricular
Years
Patients -13 Months Old Patients 13-4 Months Old All Patients
Total Hospital Deaths No.
%
Total Hospital Deaths No. % Total Hospital Deaths-No. % 1955 1956 1957 1958 1959 1960t 6 7 0 10 8 S 4 5 4 1 0 67 72 18 0 2 5 7 7 10 0 1 .50 S 60 0 0 2 29 0 0
* In this table and in the text the period designated by a year extends from April 1 of that year to April 1 of
the following year.
t April to October.
S 12 7 17 18 S 5 S 0 6 1 0 68 67 0 3.5 6 0 TABLE II
HOSPITAL MORTALITY AFrER REPAIR OF VENTRICULAR SEPTAL DEFECT
the bundle of His and yet to produce
com-plete and permanent repair.1
Postoperative management has been by
the methods generally used in this
institu-tion following open intracardiac
opera-tions.3
Hospital Mortality
RESULTS
The hospital mortality is indicated in
Table II. Total hospital mortality among
infants was high in 1955 and 1956, and for
this reason in the year 1957 no infants less
than 1 year of age were operated upon.
However, in that year seven patients
be-tween the ages of 1 and 2 years were
oper-ated upon without a death; for the same age
group the mortality had been 50% in 1955
and 60% in 1956.
The hospital mortality in the year 1959
and so far in 1960 has been 5%, there
hay-ing been one death among 21 infants
op-crated upon. This death occurred among the
11 infants less than 1 year of age.
Causes of Death (Table Ill)
In the years 1955 and 1956 most deaths
were from syndromes that are now
con-sidered to be the result of imperfect
per-fusion.
It
is the near absence of these corn-plications in the years 1958, 1959 and 1960that has allowed a significant reduction in
hospital mortality in these patients.
Incomplete repair of a ventricular septal
defect and complete heart block each
con-tributed to a death. These are the result of
imperfect surgical technique. Their
occur-rence has been minimized in the last 2 years
by the adoption of direct suture done in a
specffic way as previously described.1
Two deaths were related to low cardiac
output in the early postoperative period,
which was inadequately managed. It is
be-lieved that proper management might have
saved these patients. In addition, three
deaths followed severe and progressing
tachycardia in the first 6 to 12 hours after
operation. These patients likewise by
pres-ent standards were inadequately managed.
The two patients dying from late chronic pulmonary complications died on the tenth
and twelfth postoperative days. Both of
these infants had had severe and repeated
respiratory infections prior to operation, and
these infections continued into the
post-operative period and ultimately caused
death.
COMMENT
The concepts and techniques for open
intracardiac operations in the small infant
are identical with those employed in larger
patients. Deviations from ideal therapy,
while often tolerated by large patients, in
the infant usually result in death. All
Group 1955 1956 1957 1958 1959
1960
(Apr.-Oct.)
Considered to be the result of perfusion Acute early pulmonary complications
Unexpected sudden death Respiratory failure (apnea)
2 S 2 3 2 .. .. .. .
.
I .. .. .. ..Inadequate surgical procedures or improper postoperative care
Incomplete repair of ventricular septal defect
Low cardiac output, poorly treated
It
1 1
Disturbances of rhythm Complete heart block
Severe tachycardia early postoperatively
It 1
Other
Late, chronic pulmonary complications 2
* Operation done with profound hypothermia and circulatory arrest.
t Additional cause.
§One patient had resistant staphylococcal pneumonia and intractable heart failure preoperatively. Pneumonia
persisted, causing death on twelfth postoperative day. The other patient had recurrent pneumonia preoperatively.
TABLE III
CAUSES OF DEATH FOLLOWING REPAIR OF VENTRICULAR SEPTAL DEFECT
postoperative management must therefore
be more nearly perfect to ensure a high rate of survival in infants.
Considerable can be done in preparing
these infants for the operative procedure.
If possible the operation should be done
at a time when respiratory infections are
at a minimum. It is nearly always necessary
to achieve optimal digitalization and to
maintain it up to the time of operation. At
times, however, the cardiac failure and
pul-monary problems are refractory to therapy
and operation must be proceeded with in
spite of these (Fig. 3).
The management of the infant in the
operating room must be precise. The use of
an inhalation agent, halothane, has seemed
ideal for maintenance of anesthesia. The
patient is awake and breathing well
im-mediately after operation. Median
ster-notomy incision allows the operative
pro-cedure to be done with minimal mechanical
interference with ventilation in the
post-operative period. A totally adequate
whole-body perfusion seems essential in these sick,
small babies. The arterial cannula should be
placed in the common iliac artery rather
than in the external iliac or femoral artery
in order that high flow rates can be
main-tamed without a severe pressure gradient
across the cannula. Particular care must be
taken in the positioning of the venous
cannulas lest they become kinked or
ob-struct the delicate hepatic or innominate
veins. The sick, small heart must be handled
gently, and this is greatly facilitated by the
use of cardiac asystole. There continues to
be little if any clinical evidence that cardiac
asystole induced by ischemia is deleterious
to these patients. A small right
ventricu-lotomy produces minimal reduction of
cardiac output in the postoperative period.
Accurate visualization of the defect and its
complete and accurate repair without the
production of heart block offer the infant
the most favorable circumstances for
sur-vival.
Extremely close attention to the infant in
the early hours after operation is
manda-tory.
If
progressing tachycardia develops,prompt use of digitalis to control it is
FIG. 3. Left) Preoperative roentgenogram of 9-month-old infant with intractable cardiac failure and persistent severe atelectasis of the left lung. It was necessary to proceed with operation in the face of this severe atelectasis. Right) Six months after operation. The heart has returned to its proper position
with re-expansion of the left lung. There is emphysema of this lung.
965
monitoring the electrocardiogram as small
doses of digitalis are injected intravenously until the desired effect is obtained.
Tracheotomy has been employed in none
of these patients treated in the last 3 years,
save in one infant who died 12 days after
operation of continuing chronic pulmonary infection. On about the tenth postoperative day, tracheotomy was done in this patient in
the hope that it would permit better
aspira-tion of the tracheobronchial tree.
The late results in infants operated upon
are excellent. Without exception the
pa-tients have been relieved of cardiac failure,
respiratory infections have cleared, and
gain in weight has been striking. The in-fants appear to be cured when seen 6 to 12 months after operation.
In view of these surgical results,
com-ment is indicated upon the fate of surgically
untreated infants. Those with large
yen-tricular septal defects frequently thrive in
the neonatal period but develop cardiac
failure at about the age of 2 to 3 months.
This course of events is presumably related
to pulmonary vascular resistance present in
the fetus and the normal involution of these
fetal characteristics in the small pulmonary
arteries with consequent reduced
pulmo-nary vascular resistance and increased
pul-monary blood flow. Untreated, such infants
may die as a result of pulmonary
conges-tion alone or in combination with
super-imposed pulmonary 5 The
mor-tality has been estimated to approach 50 to
60%. With vigorous medical measures to
combat cardiac failure, a substantial
num-her of such infants develop a favorable
balance between the abnormal
hemody-namics associated with the large
ventricu-lar septal defect and the ability of the heart
to adjust to these events. This favorable
response may result in resumption of weight gain and general good health. On the other hand the response may be minimal,
allow-ing survival of the infant but with failure to thrive and increased susceptibility to the
hazards of intercurrent pulmonary
infec-tions. In this latter group of infants the
mortality may approach 15 to 25%. Of equal
importance as to the ultimate prognosis is
the fact that gain in weight is slow, and
frequently such babies weigh only 14 or 15
lb (6,350 to 6,800 gm) at the age of 2 years.
Also, some are prone to develop high
SEPTAL DEFECT
in life with reduced pulmonary blood flow,
a situation producing an unfavorable
hemo-dynamic response to surgical closure of the
ventricular septal defect.
It is difficult to predict whether an
mdi-vidual infant first seen in cardiac failure
will respond promptly and satisfactorily to
medical treatment or will follow the
in-dolent course described above. Therefore,
an intensive medical regimen should be in-stituted. If the child thrives, surgical treat-ment is postponed until about 4 years of
age. If the infant does poorly after a fair
trial of an anticardiac-failure regimen,
prompt surgical treatment is recommended.
SUMMARY
Data on 65 infants treated surgically for
ventricular septal defect by open
intra-cardiac repair are presented, and important
features of the preoperative, operative and
postoperative care are discussed. The low
hospital mortality following surgical repair
during a 2-year period and the excellent
results support the present policy of
recom-mending operation
.
for infants who fail tothrive under medical management.
REFERENCES
1. Kirklin, J. W., McCoon, D. C., and DuShane,
J. W. : Surgical treatment of ventricular septal
defect. J. Thor. Surg., 40:763, 1960. 2. Brown, I. W., Jr., Smith, W. W., and Emmons,
W. 0. : An efficient blood heat exchanger for
use with extracorporeal circulation. Surgery, 44:372, 1958.
3. Lyons, W. S., DuShane,
J.
W., and Kirklin,J.
W. : Postoperative care after whole-body perfusion and open intracardiac operations: use of Mayo-Gibbon pump-oxygenator and Brown-Emmons heat exchanger. J.A.M.A., 173:625, 1960.4. Dawson, B., Theye, R. A., and Kirklin, J. W.: Halothane in open cardiac operations : A
tech-nic for use with extracorporeal circulation.
Anesth. & Analg., 39:59, 1960.
5. Morgan, B. C., Grifliths, S. P., and Blumenthal, S.: Ventricular septal defect: I. Congestive
heart failure in infancy. Pviwrmcs, 25:54,