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ISOLATED INFUNDIBULAR STENOSIS
ISOLATED I N F U N D I B U L A R STENOSIS P. R. Slade, Ch.M., F.R.C.S., London,
D
England
the past 18 months, 13 patients with isolated infundibular stenosis have been operated upon in Brompton and St. Bartholomew's Hospitals in London. As this is a relatively uncommon condition, Abbott quotes only 2 examples in 1,000 autopsies and Campbell only 2 cases in his series of 1,130 patients with congenital heart disease, a review of a recent series may be of interest. The clinical features are summarized in Table I. There were 7 female and 6 male patients. Twelve were of European and one of Indian nationality. URING
CLINICAL FINDINGS
Symptoms.—Effort dyspnea was the only symptom and all patients complained of this to some degree. A heart murmur had always been noted a long time prior to the onset of dyspnea. Many patients with very high resting right ventricular pressure had only slight dyspnea; but even moderately severe symptoms, being of late onset, probably indicate an advanced stage of the disease. Three patients had had attacks of subacute bacterial endocarditis due to Streptococcus viridans and all had been successfully treated with penicillin. Physical Signs.—All patients had a normal physique. The jugular venous pulse showed a dominant " a " wave and there was some correlation between the height of the " a " wave and the severity of the stenosis. There was a pulmonary ejection systolic murmur usually accompanied by a thrill, with the second pulmonic sound soft and delayed. Fig. 1 shows a typical phonocardiogram. Vogelpoel and Schrire 3 have pointed out that the length of the murmur and degree of delay in P 2 may be a guide to the severity of the stenosis. The only case (No. 8) with right ventricular pressure less than 100 mm. Hg systolic had a relatively short murmur with P 2 well heard without much delay. Electrocardiogram.—Table I I shows the electrocardiographic changes related to the right ventricular pressures found at catheterization. In pure pulmonary valve stenosis, Engle and his associates4 have shown that the electrocardiographic changes are a good guide to the severity of the stenosis and this was the usual finding in this series. The electrocardiogram of a patient with a Prom the Brompton and St. Bartholomew's Hospitals, London, England. Received for publication Nov. 5, 1962. 775
SLADE
776
J. Thoracic and Cardiovas. Surg. TABLE I .
SEX
AGE (YEARS)
AGE WHEN MURMUR FIRST NOTED (YEARS)
1 M.B.
M
26
13
Moderate
1
Sinus
2 S. M.
F .
28
3
Moderate
IV2
Sinus
3 J . C.
F
36
3
Moderate
IV2
Sinus
4 J.F.
F
33
5
Slight
10
Sinus
5 G. S.
F
32
18
Slight
2
Sinus
6 E. P.
M
10
5
Slight
5
Sinus
7 K. E.
F
28
1
Severe
IV2
Sinus
8 P. G.
M
14
3
Slight
9 F. C.
M
12
10
10 T. Y.
M
9
11 M. D.
F
12 M. H. 13 G. 0 .
CASE NO.
DEGREE OF EFFORT DYSPNEA
DURATION OF EFFORT DYSPNEA (YEARS)
10
PULSE RHYTHM
SUMMARY off
H E I G H T OF " a " WAVE IN JUGULAR VENOUS P U L S E ABOVE STERNAL ANGLE W I T H PATIENT ( C M . ) AT 3 0 DEGREES
Sinus
Moderate
1%
Sinus
1
Slight
3
Sinus
10
1
Moderate
2
Sinus
F
29
8
Slight
4
Sinus
M
46
23
Moderate
l¥i
Sinus
severe case is shown in Fig. 2. However, 2 patients with resting right ventricular pressures greater than 100 mm. Hg systolic had only minor electrocardiographic changes of right ventricular hypertrophy. Chest X-Ray Examination.—The vascularity of the lung fields was reduced. The pulmonary artery was not dilated. The right atrium was prominent and the left border of the heart straight or slightly convex, due to the presence of an infundibular chamber (Fig. 3). In advanced cases, enlargement of the transverse diameter of the heart was seen (Fig. 4). Cardiac Catheterization.—The findings are given in Table III. An infundibular chamber was demonstrated in all except 2 cases. But in these cases, Nos. 1 and 5, the diagnosis was suspected because the pressure change occurred at a low level. At operation in these 2 cases the pulmonary ring was so greatly dilated that a second pressure change across the pulmonary valve could not
Vol.45. No. 6 June, 1963
ISOLATED I N F U N D I B U L A R STENOSIS
777
CLINICAL FEATURES
TYPE OP CARDIAC IMPULSE
CHARACTER OF SYSTOLIC MURMUR AND SITE OF MAXIMUM INTENSITY
NATURE OF P 2 AND T I M I N G ON PHONOCARDIOGRAM
EJECTION CLICK
RV PRESSURE AT CATHETERIZATION ( M M . HG)
RV++
Very long 2nd left space
Soft Delayed 0.07 sec.
Absent
120/0
RV +
Long 2nd left space
Soft Delayed
Absent
140/0
RV +
Long 3rd left space
Inaudible
Absent
106/0
RV +
Very long 2nd left space
Soft Delayed 0.06 sec.
Absent
125/0
RV +
Long 2nd left space
Soft Delayed 0.08 sec.
Absent
100/10
RV +
Long 2nd left space
Soft Delayed 0.06 sec.
Absent
155/0
RV++
Long 3rd left space
Inaudible Not seen on phonocardiogram
Absent
175/0
RV +
Only up to A, 2nd left space
P . slightly delayed only
Absent
82/5
RV +
Long 3rd left space
Very soft and long delay
Absent
160/0
RV++
Long 2nd left space
Inaudible
Absent
125/2
RV +
Long 2nd left space
Soft Delayed 0.07 sec.
Absent
170/0
RV++
Long 2nd left space
Soft Delayed 0.06 sec.
Absent
165/5
RV +
Long 3rd left space
Inaudible
Absent
120/0
be expected. As can be seen from Fig. 5, an intracardiac electrocardiograph electrode may be helpful in showing that the low pressure zone is within the heart. The height of the right ventricular pressure is probably the most important single factor in deciding on the need for treatment. Symptoms, roentgenographic, and electrocardiographic changes all occur late in the disease. DIFFERENTIATION FROM PULMONARY VALVE STENOSIS
The points which may be helpful in distinguishing pure valvar from pure infundibular stenosis follow. 1. Site of maximum intensity of the murmur. Opinions vary; Blount and his colleagues5 state that it was a very good indication of the site of the stenosis but Vogelpoel and Schrire 3 have not found it to be helpful. In this series the site of maximum intensity was lower in only 4 cases.
20 9 5 5 50 30 15 12 15 45 35
Bight
Eight
Eight
Eight
Eight
Eight
Bight
Eight
Bight
Bight
Bight
Bight
Bight
26
28
36
33
32
10
28
14
12
9
10
29
46
1 M.B.
2 S.M.
3 J. C
4 J.F.
5 G. S.
6 B. P .
7 K.B.
8 P . G.
9 F . C.
10 T. Y.
11 M. D.
12 M. H.
13 G.O.
4
10
AXIS
CASE NO.
AGE (YEARS)
FEATURES COMPARED W I T H BV
Absent
Absent
Absent
Absent
Absent
Absent
Present
Absent
Present
Absent
Absent
Present
Present
P PULMONALE
2
0
8
0
3
3
0
0
2
0
3
0
4
DEPTH S WAVE I N V„ (MM.)
ELECTROCARDIOOBAPHIC CHANGES
ECG
HEIGHT R WAVE I N V t (MM.)
TABLE I I .
Present
Absent
Absent
Absent
Absent
Absent
Present
Absent
Absent
Absent
Absent
Absent
Absent
QR I N Vj
PRESSURES
v,,,
v,.,
v,_«
V,
None
None
^ - 5
v,, 2
None
None
None
v.-,
v,.4
T-WAVE INVERSION
120/0
165/5
170/0
125/2
160/0
82/5
175/0
155/0
100/10
125/0
106/0
140/0
120/0
RV
135/68
100/60
135/85
125/80
95/65
110/70
125/75
80/55
100/80
98/60
95/45
90/60
110/64
BRACHIAL ARTERY
PRESSURES AT CATHETERIZATION (MM. HG)
25/6
11 M. D. 12 M. H. 13 G. 0 .
120/0
125/80
10 T. Y.
135/68
160/0
95/65
60/5
_
82/1
120/75
165/5
20/6
175/0
125/75
100/60
10/0
155/0
80/55
80/0
14/2
100/10
100/80
5 G. S. 6 B. P . 7 K. E. 8 P. G. 9 F . C.
170/0
13/3
125/0
98/66
135/85
37/2
106/0
95/42
35/2
17/0
140/0
90/60
2 S. M. 3 J.C. 4 J. F.
125/2
20/0
120/0
110/64
1 M.B.
25/5
12/3
12/6
12/7
12/6
24/8
8/0
13/5
15/3
16/6
17/3
7/3
13/4
-
RV PRESSURE (MM. HG)
CASE NO.
PA PRESSURE (MM. HG)
INFUNDIBULUM PRESSURE (MM. HG)
96
95
95
92
5
-
3.9
5.3
4.8
-
5.2
98
4.5
3.4
-
3.0
4.7
CARDIAC OUTPUT (L./MIN.)
96
95
-
-
98
(%)
BRACHIAL ARTERY SATURATION
No shunt
No shunt
RV
VSD
None
None
Present
Present
Present
Present
Present
Present
-
None
None
125/5
80/45
125/5 Present
125/0
_
120/0 None
120/0
None
|
-
75/40
No shunt No shunt
-
No shunt
-
No shunt
80/60
No shunt
-
_
No shunt
No shunt
52/21
No shunt
-
-
No shunt
No shunt
90/50
BA
PRESSURES AFTER AMYL NITRTTIT (MM. HG)
No shunt
0 2 SATURATION AND DYE CURVES
FINDINGS AT CARDIAC CATHETERIZATION
BRACHIAL ARTERY PRESSURE (MM. HG)
TABLE I I I .
REMARKS
Withdrawal tracing does show a double change of pressure 0 2 saturation fell from 95 to 9 3 % on exercise
0 2 saturation fell from 95 to 9 2 % on exercise 0 2 saturation; no fall on exercise
Single change of pressure at low level 0 2 saturation did not fall on exercise
780
SLADE
J. Thoracic and Cardiovas. Surg.
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Fig. 2.—Electrocardiogram of Case 7 shows severe changes of right ventricular hypertrophy.
Vol. 45, No. 6 June. 1963
ISOLATED I N F U N D I B U L A R STENOSIS
781
Fig. 3.—Chest roentgenogram of case of moderate severity.
Fig. 4.—Chest roentgenogram of an advanced case shows much right ventricular enlargement
782
SLADE
J. Thoracic and Cardiovas. Surg.
2. Absence of an ejection click. No click was heard in any of the cases reported here but, of course, a click is not heard in many cases of severe pulmonary valvular stenosis. 3. Absence of post-stenotic dilatation of the pulmonary artery on the chest roentgenogram. In none of these cases was there any post-stenotic dilatation shown on the chest films. But again post-stenotic dilatation is not an invariable finding with valvular stenosis. 4. A selective angiocardiogram will show the level of stenosis accurately (Fig. 6). The information obtained is also useful in planning the incision in the heart. 5. Cardiac catheterization. This is usually reliable but difficulty may be experienced if there is a very high infundibular stenosis with dilatation of the valve ring.
Fig. 5.—Catheter withdrawal tracing with intracardiac electrocardiographic electrode shows ventricular complexes in the infundibular zone.
Association With a Small Ventricular Septal Defect.—Before the condition was frequently operated upon under cardiopulmonary bypass, an associated ventricular septal defect (VSD) was not often reported. Thus Glover7 quoted 4 cases of patients treated by closed operation with no VSD. Brock6 had 12 patients, 6 treated by closed resection and 6 by resection under conventional hypothermia. A VSD was only noted in one of the fatal cases which came to post mortem. Swan and his co-workers12 reported cases of 8 patients operated upon under conventional hypothermia who had no evidence of any VSD. However, apart from "Williams and his associates16 who quote cases of 3 patients without VSD, all authors who have performed operations with cardiopulmonary bypass have found a high incidence of associated VSD. McGoon and Kirklin 8 found a VSD in 2 of their 3 cases. Vogelpoel and Schrire 3 found a VSD in 2 of 8 cases—Gerbode9 found a VSD in one of 2 cases, and Hoffman and his colleagues 1 ' one in both of their cases. In this series, a VSD was present in 7 of the 13 cases. The association of a small VSD with pulmonary valvular stenosis seems to be much less frequent. Gerbode9 noted only one small VSD in 29 cases of pulmonary valvular stenosis. In all reported cases, the VSD has been small, not more than 8 mm. in
Vol. 45, No. 6 June, 1963
ISOLATED I N F U N D I B U L A R STENOSIS
783
Pig. 6.—Angiocardiogram of Case 3 shows a large infundibular chamber.
Fig. 7.- -Heart of Case 7. The arrow shows the site of the small ventricular septal defect. The hypertrophy of the right ventricular muscle is also demonstrated.
SLADE
784
J. Thoracic and Cardiovas. Surg. TABLE
CASE NO.
SIZE OF INFUNDIBULAR STENOSIS
SITE OF S T E N O S I S AND SIZE OF I N FUNDIBULAR CHAMBER
SIZE OF VSD (MM.) —
POSITION OF VSD
IV.
P R E S S U R E S BEFORE OPERATION ( M M . H G ) PA
INF.
17/12
16/11
-
20/10
20/10 200/10
-
22/11
28/9
78/8
High Infra-CSV*
20/0
50/0
80/0
7x6
Under tricuspid valve
20/5
25/0
60/0
Low Large
3x3
Infra-CSV
20/2
50/0
170/0
0.75 cm. dia.
Fairly high Small
7x7
High Infra-CSV
12/0
12/0
158/0
8 P . G.
0.8 cm. dia.
Low Large
5x3
Under tricuspid valve
28/10
38/2
78/2
9 F . C.
0.6 cm. dia.
High Small
6x2
High Infra-CSV
24/8
-
172/6
10 T.Y.
0.5 cm. x 1.0 cm.
High Small
5x5
High Infra-CSV
5/0
75/0
100/0
11 M. D.
0.5 cm. dia.
High Very small
-
-
25/10
30/0
200/0
12 M. H.
0.6 cm. dia.
Medium Fairly large, 2 x 2 cm.
-
-
25/10
25/10 130/10
13 G. 0 .
1.0 cm. dia.
30/10
30/5
1 M.B.
0.5 cm. dia.
Low Fairly large
2 S. M.
0.6 cm. dia.
Low Large, 3 x 3 cm.
-
3 J . C.
0.75 cm. dia.
Low Very large
-
4 J. F .
0.75 cm. dia.
Medium Moderate size
3x4
5 G. S.
0.75 cm. dia.
Medium Moderate
6 R. P .
1.0 cm. dia.
7 K. E.
•CSV
High (2 cm. below valve ) Small Crista supraventricularis.
|
RV
80/10
120/5
diameter, and the infundibular stenosis is the important factor. As Hoffman and co-workers17 have suggested, it is probable that these small defects are not functional. In this series, two of the defects lay under the septal cusp of the tricuspid valve, the others were in the thickened muscle just under the crista supraventricularis and appeared to be at least partially closed during ventricular systole. Fig. 7 shows the heart of a patient of one of the fatal cases with the small VSD sutured. It is possible that shunting will occur as the right ventricular pressure falls and it is, therefore, advisable to close the VSD at operation.
785
ISOLATED I N F U N D I B U L A R STENOSIS
Vol. 45, N o . 6 June. 1963 OPERATIVE FINDINGS
PRESSURES AFTER OPERATION ( M M . H G ) INF.
RV
26/11
27/12
30/7
Transverse, through infundibulum
Good Still has pulmonary insufficiency
20/10
20/5
30/0
Transverse, through infundibulum
Good
25/15
27/9
27/9
Transverse, through infundibulum
Good
30/10
25/10
25/10
Vertical in RV
Good
Murmur abolished
16/5
16/5
20/4
Vertical in RV
Died 7th day
Abnormal coronary artery pattern
30/7
35/7
60/7
Transverse, in inf undibulum
Good
18/5
18/5
25/5
Vertical
Died
Muscle hypertrophy ++ Difficulty in suturing RV
24/13
30/4
34/5
Transverse, in infundibulum
Good
Murmur abolished
48/6
Transverse in RV
Good
Abnormal coronary artery pattern
18/6
OPERATIVE APPROACH
RESULTS
REMARKS
Pulmonary ring greatly dilated
15/0
25/0
50/0
Vertical in RV
Died 48 hr. postop.
Cardiac output in postop. poor; some possible cerebral complication
25/10
35/0
50/0
Vertical in RV
Died 30 hr. postop.
Cardiac output poor first few hours after operation
25/20
25/10
30/15
Vertical through RV & infundibulum
Good
30/5
Vertical in RV only
Good
30/15
Murmur abolished
Dye curves and oxygen saturations at cardiac catheterization have not proved helpful in showing up the VSD. Right ventricular and systemic pressures were separated by inhalations of amyl nitrite, whether a VSD was present or not. In 2 patients with an associated VSD, the oxygen saturation fell on exercise and, in one of these cases, amyl nitrite inhalations produced cyanosis, but these tests were not positive in other cases of associated VSD. In both of these cases, although the VSD was small it was less tucked away under the muscle mass of the crista supraventricularis than in the other cases reported here. Angiocardiograms taken at 6 frames a second did not shown up the defects, but in Case 9 a cine-angiocardiogram showed the VSD very nicely.
SLADE
786
J. Thoracic and Cardiovas. Surg.
TREATMENT
Operations were performed in 12 cases with the use of a Melrose type heart-lung machine and, in one case, with profound hypothermia by the Drew technique. Swan and his co-workers12 have obtained good results using conventional hypothermia but, with this method, operating time is limited and it may be argued that patients such as these, with greatly thickened ventricles, benefit from the support given by an extracorporeal circulation. In this series the deaths were due to cardiac failure in the early postoperative period. In all the cases reported here there was a localized stenosis of thick, white, fibro-endocardial tissue occurring at varying levels. The long stenotic infundibulum described by Lev11 was not encountered. As Blount and his associates5 have pointed out, the crista supraventricularis and its bands are usually abnormal and division of some part of the hypertrophied bands is often required as well as resection of the actual stenotic area. Grant and his co-workers,13 in their study of the architecture of the right ventricular muscle, suggest that defects in the inner layer give abnormal cristal bands and localized stenoses, whereas defects of the outer layer are likely to result in a VSD. Hence the association of the two conditions is theoretically a strong possibility and infundibular stenosis is only at one end of the spectrum of developmental abnormality of the musculature of the right ventricle which is represented in the most severe form by the tetralogy of Pallot. Brock10 has drawn attention to the fact that the hypertrophied muscle in this type of heart is unhealthy. Histological examination of the myocardium in a fatal case (No. 7) showed much fibrosis and hydropic degeneration of the sarcoplasm. A ventriculotomy will further impair the efficiency of the heart, and incisions in this type of heart muscle are often difficult to close. In Case 7 in this series, the ventriculotomy could only be closed after prolonged efforts and the use of Teflon patches. Where a good-sized infundibular chamber has been present, a transverse incision through the chamber has given good access, both for relief of the stenosis and repair of any VSD that is present. This incision was used in 5 cases and was always easy to close; it appeared to interfere very little with the action of the heart. However, when the stenosis is at a higher level, an approach through the right ventricle is necessary. A very real problem in these cases appears to be failure of cardiac output in the immediate postoperative period. Both March14 and Sanger 15 and their colleagues have demonstrated that transverse incisions interfere less with the function of the right ventricle than vertical incisions. In this series, in all the fatal cases there had been a vertical incision in the right ventricle. A further argument for the use of a transverse incision is that abnormally large branches of the right coronary artery are often crossing the outflow part of the right ventricle and may possibly be spared by a transverse ventriculotomy. Such arteries were present in 3 of the cases in this series. In all 7 cases, the small VSD was easily closed by direct suture.
Vol. 45, No. 6 June, 1963
ISOLATED I N F U N D I B U L A R STENOSIS
787 l o '
RESULTS
Four patients died as a result of the operation. In 3 of these cases the cardiac output was never well maintained from the time of operation and death occurred within the first 48 hours. The fourth patient lived for 7 days and the course was complicated by severe postoperative hemorrhage, so that right ventricular failure cannot be held so directly responsible for the fatal outcome. The gradient across the stenosis was abolished at operation in 2 cases with fatal outcome and in the other cases a residual gradient of 15 and 25 mm. Hg remained. In the surviving cases the gradient was abolished in 4 cases and in the others remained from 10 to 30 mm. Hg. Inadequate relief of the stenosis does not appear to have played any part in the fatal outcome. The preoperative right ventricular pressures in the fatal instances were 100 mm. Hg, 125 mm. Hg, 170 mm. Hg, and 175 mm. Hg, so that this group contained 2 patients with the highest right ventricular pressures in the series. Long-standing obstruction undoubtedly causes severe damage to the right heart and surgical treatment may not be well tolerated. All the surviving patients have been followed up for a minimum of 6 months. None have any symptoms. In 3 cases the murmur has been abolished, and, in the remainder, the systolic murmur is short with the pulmonary element of the second heart sound audible although usually showing some delay. In all cases, the electrocardiogram has shown some regression of the changes of right ventricular hypertrophy. SUMMARY
Thirteen cases of isolated infundibular stenosis are reported. The physical signs and investigations are discussed. A small ventricular septal defect was present in 7 cases. Surgical treatment gave good results but there were 4 deaths. My thanks are due the physicians and surgeons under whose care these patients were treated—Drs. E. V. Gibson, 6 . W. Hayward, W. Oliver, and P . Wood, Sir B. C. Brock, Mr. W. P. Cleland, Mr. M. Paneth, and Mr. O. S. Tubbs. REFERENCES 1. Abbott, M.: Atlas of Congenital Heart Disease, New York, 1936, American Heart Association. 2. Campbell, M.: Simple Pulmonary Stenosis, Brit. Heart J . 16: 273, 1954. 3. Vogelpoel, L., and Schrire, V.: Auscultatory and Phonocardiographic Assessment of Pulmonary Stenosis, Circulation 22: 55, 1960. 4. Engle, M. A., Ito, T., Lucas, O. S., and Goldberg, H. P . : Electrocardiogram in Pulmonary Stenosis, J . Pediatrics 57: 171, 1960. 5. Blount, S. G., Vigoda, P . S., and Swan, H . : Isolated Infundibular Stenosis, Am. Heart ' J . 57: 684, 1959. 6. Brock, E. C.: Isolated Infundibular Stenosis in Advances in Cardiology, Basel/New York, 1959, S. Karger, vol. 2, p. 44. 7. Glover, B. P., O'Neill, T. J . E., Goantigo, H., McAuliffe, T. C , and Wells, C. E. E . : Surgery of Infundibular Pulmonary Stenosis, J . THORACIC SURG. 28: 481, 1954. 8. McGoon, D. C , and Kirklin, J . W . : Pulmonic Stenosis With Intact Ventricular Septum, Circulation 17: 180, 1958. 9. Gerbode, F., Eoss, J . K., Harkins, G. A., and Osborn, J . J . : Surgical Treatment of Pulmonic Stenosis Using Extracorporeal Circulation, Surgery 48: 58, 1960. 10. Brock, E. C : Surgical Treatment of Pulmonary Stenosis, Brit. Heart J . 23: 337, 1961.
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11. Lev, M.: Autopsy Diagnosis of Congenitally Deformed Hearts, Springfield, 111., 1953, Charles C Thomas, Publisher. 12. Swan, H., Hederman, W. P., Vigoda, P . S., and Blount, S. G., J r . : Surgical Treatment of Isolated Infundibular Stenosis, J . THORACIC SURG. 38: 319, 1959. 13. Grant, E. P., Downey, F . M., and MacMahon, H . : Architecture of Bight Ventricular Outflow Tract, Circulation 24: 223, 1961. 14. March, H. W., Boss, K. J., Weirich, W. L., and Gerbode, F . : Influence of Ventriculotomy Site on Contraction and Function of Right Ventricle, Circulation 24: 572, 1961. 15. Sanger, P . W., Bobicsek, F., Taylor, F . H., and Davis, S. C.: Method of Preventing Myocardial Damage by Using Modified Ventriculotomy Incision, Ann. Surg. 156: 874, 1962. 16. Williams, G. R., Richardson, W. R., Cayler, G. C , and Campbell, G. C.: Infundibular Pulmonic Stenosis With Intact Ventricular Septum, Am. Surgeon 27: 307, 1961. 17. Hoffman, J . I. E., Rudolph, A. M., Nadas, A. S., and Gross, R. E.: Pulmonic Stenosis, Ventricular Septal Defect, and Right Ventricular Pressure Above Systemic Level, Circulation 22: 405, 1960.
D
England
the past 18 months, 13 patients with isolated infundibular stenosis have been operated upon in Brompton and St. Bartholomew's Hospitals in London. As this is a relatively uncommon condition, Abbott quotes only 2 examples in 1,000 autopsies and Campbell only 2 cases in his series of 1,130 patients with congenital heart disease, a review of a recent series may be of interest. The clinical features are summarized in Table I. There were 7 female and 6 male patients. Twelve were of European and one of Indian nationality. URING
CLINICAL FINDINGS
Symptoms.—Effort dyspnea was the only symptom and all patients complained of this to some degree. A heart murmur had always been noted a long time prior to the onset of dyspnea. Many patients with very high resting right ventricular pressure had only slight dyspnea; but even moderately severe symptoms, being of late onset, probably indicate an advanced stage of the disease. Three patients had had attacks of subacute bacterial endocarditis due to Streptococcus viridans and all had been successfully treated with penicillin. Physical Signs.—All patients had a normal physique. The jugular venous pulse showed a dominant " a " wave and there was some correlation between the height of the " a " wave and the severity of the stenosis. There was a pulmonary ejection systolic murmur usually accompanied by a thrill, with the second pulmonic sound soft and delayed. Fig. 1 shows a typical phonocardiogram. Vogelpoel and Schrire 3 have pointed out that the length of the murmur and degree of delay in P 2 may be a guide to the severity of the stenosis. The only case (No. 8) with right ventricular pressure less than 100 mm. Hg systolic had a relatively short murmur with P 2 well heard without much delay. Electrocardiogram.—Table I I shows the electrocardiographic changes related to the right ventricular pressures found at catheterization. In pure pulmonary valve stenosis, Engle and his associates4 have shown that the electrocardiographic changes are a good guide to the severity of the stenosis and this was the usual finding in this series. The electrocardiogram of a patient with a Prom the Brompton and St. Bartholomew's Hospitals, London, England. Received for publication Nov. 5, 1962. 775
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776
J. Thoracic and Cardiovas. Surg. TABLE I .
SEX
AGE (YEARS)
AGE WHEN MURMUR FIRST NOTED (YEARS)
1 M.B.
M
26
13
Moderate
1
Sinus
2 S. M.
F .
28
3
Moderate
IV2
Sinus
3 J . C.
F
36
3
Moderate
IV2
Sinus
4 J.F.
F
33
5
Slight
10
Sinus
5 G. S.
F
32
18
Slight
2
Sinus
6 E. P.
M
10
5
Slight
5
Sinus
7 K. E.
F
28
1
Severe
IV2
Sinus
8 P. G.
M
14
3
Slight
9 F. C.
M
12
10
10 T. Y.
M
9
11 M. D.
F
12 M. H. 13 G. 0 .
CASE NO.
DEGREE OF EFFORT DYSPNEA
DURATION OF EFFORT DYSPNEA (YEARS)
10
PULSE RHYTHM
SUMMARY off
H E I G H T OF " a " WAVE IN JUGULAR VENOUS P U L S E ABOVE STERNAL ANGLE W I T H PATIENT ( C M . ) AT 3 0 DEGREES
Sinus
Moderate
1%
Sinus
1
Slight
3
Sinus
10
1
Moderate
2
Sinus
F
29
8
Slight
4
Sinus
M
46
23
Moderate
l¥i
Sinus
severe case is shown in Fig. 2. However, 2 patients with resting right ventricular pressures greater than 100 mm. Hg systolic had only minor electrocardiographic changes of right ventricular hypertrophy. Chest X-Ray Examination.—The vascularity of the lung fields was reduced. The pulmonary artery was not dilated. The right atrium was prominent and the left border of the heart straight or slightly convex, due to the presence of an infundibular chamber (Fig. 3). In advanced cases, enlargement of the transverse diameter of the heart was seen (Fig. 4). Cardiac Catheterization.—The findings are given in Table III. An infundibular chamber was demonstrated in all except 2 cases. But in these cases, Nos. 1 and 5, the diagnosis was suspected because the pressure change occurred at a low level. At operation in these 2 cases the pulmonary ring was so greatly dilated that a second pressure change across the pulmonary valve could not
Vol.45. No. 6 June, 1963
ISOLATED I N F U N D I B U L A R STENOSIS
777
CLINICAL FEATURES
TYPE OP CARDIAC IMPULSE
CHARACTER OF SYSTOLIC MURMUR AND SITE OF MAXIMUM INTENSITY
NATURE OF P 2 AND T I M I N G ON PHONOCARDIOGRAM
EJECTION CLICK
RV PRESSURE AT CATHETERIZATION ( M M . HG)
RV++
Very long 2nd left space
Soft Delayed 0.07 sec.
Absent
120/0
RV +
Long 2nd left space
Soft Delayed
Absent
140/0
RV +
Long 3rd left space
Inaudible
Absent
106/0
RV +
Very long 2nd left space
Soft Delayed 0.06 sec.
Absent
125/0
RV +
Long 2nd left space
Soft Delayed 0.08 sec.
Absent
100/10
RV +
Long 2nd left space
Soft Delayed 0.06 sec.
Absent
155/0
RV++
Long 3rd left space
Inaudible Not seen on phonocardiogram
Absent
175/0
RV +
Only up to A, 2nd left space
P . slightly delayed only
Absent
82/5
RV +
Long 3rd left space
Very soft and long delay
Absent
160/0
RV++
Long 2nd left space
Inaudible
Absent
125/2
RV +
Long 2nd left space
Soft Delayed 0.07 sec.
Absent
170/0
RV++
Long 2nd left space
Soft Delayed 0.06 sec.
Absent
165/5
RV +
Long 3rd left space
Inaudible
Absent
120/0
be expected. As can be seen from Fig. 5, an intracardiac electrocardiograph electrode may be helpful in showing that the low pressure zone is within the heart. The height of the right ventricular pressure is probably the most important single factor in deciding on the need for treatment. Symptoms, roentgenographic, and electrocardiographic changes all occur late in the disease. DIFFERENTIATION FROM PULMONARY VALVE STENOSIS
The points which may be helpful in distinguishing pure valvar from pure infundibular stenosis follow. 1. Site of maximum intensity of the murmur. Opinions vary; Blount and his colleagues5 state that it was a very good indication of the site of the stenosis but Vogelpoel and Schrire 3 have not found it to be helpful. In this series the site of maximum intensity was lower in only 4 cases.
20 9 5 5 50 30 15 12 15 45 35
Bight
Eight
Eight
Eight
Eight
Eight
Bight
Eight
Bight
Bight
Bight
Bight
Bight
26
28
36
33
32
10
28
14
12
9
10
29
46
1 M.B.
2 S.M.
3 J. C
4 J.F.
5 G. S.
6 B. P .
7 K.B.
8 P . G.
9 F . C.
10 T. Y.
11 M. D.
12 M. H.
13 G.O.
4
10
AXIS
CASE NO.
AGE (YEARS)
FEATURES COMPARED W I T H BV
Absent
Absent
Absent
Absent
Absent
Absent
Present
Absent
Present
Absent
Absent
Present
Present
P PULMONALE
2
0
8
0
3
3
0
0
2
0
3
0
4
DEPTH S WAVE I N V„ (MM.)
ELECTROCARDIOOBAPHIC CHANGES
ECG
HEIGHT R WAVE I N V t (MM.)
TABLE I I .
Present
Absent
Absent
Absent
Absent
Absent
Present
Absent
Absent
Absent
Absent
Absent
Absent
QR I N Vj
PRESSURES
v,,,
v,.,
v,_«
V,
None
None
^ - 5
v,, 2
None
None
None
v.-,
v,.4
T-WAVE INVERSION
120/0
165/5
170/0
125/2
160/0
82/5
175/0
155/0
100/10
125/0
106/0
140/0
120/0
RV
135/68
100/60
135/85
125/80
95/65
110/70
125/75
80/55
100/80
98/60
95/45
90/60
110/64
BRACHIAL ARTERY
PRESSURES AT CATHETERIZATION (MM. HG)
25/6
11 M. D. 12 M. H. 13 G. 0 .
120/0
125/80
10 T. Y.
135/68
160/0
95/65
60/5
_
82/1
120/75
165/5
20/6
175/0
125/75
100/60
10/0
155/0
80/55
80/0
14/2
100/10
100/80
5 G. S. 6 B. P . 7 K. E. 8 P. G. 9 F . C.
170/0
13/3
125/0
98/66
135/85
37/2
106/0
95/42
35/2
17/0
140/0
90/60
2 S. M. 3 J.C. 4 J. F.
125/2
20/0
120/0
110/64
1 M.B.
25/5
12/3
12/6
12/7
12/6
24/8
8/0
13/5
15/3
16/6
17/3
7/3
13/4
-
RV PRESSURE (MM. HG)
CASE NO.
PA PRESSURE (MM. HG)
INFUNDIBULUM PRESSURE (MM. HG)
96
95
95
92
5
-
3.9
5.3
4.8
-
5.2
98
4.5
3.4
-
3.0
4.7
CARDIAC OUTPUT (L./MIN.)
96
95
-
-
98
(%)
BRACHIAL ARTERY SATURATION
No shunt
No shunt
RV
VSD
None
None
Present
Present
Present
Present
Present
Present
-
None
None
125/5
80/45
125/5 Present
125/0
_
120/0 None
120/0
None
|
-
75/40
No shunt No shunt
-
No shunt
-
No shunt
80/60
No shunt
-
_
No shunt
No shunt
52/21
No shunt
-
-
No shunt
No shunt
90/50
BA
PRESSURES AFTER AMYL NITRTTIT (MM. HG)
No shunt
0 2 SATURATION AND DYE CURVES
FINDINGS AT CARDIAC CATHETERIZATION
BRACHIAL ARTERY PRESSURE (MM. HG)
TABLE I I I .
REMARKS
Withdrawal tracing does show a double change of pressure 0 2 saturation fell from 95 to 9 3 % on exercise
0 2 saturation fell from 95 to 9 2 % on exercise 0 2 saturation; no fall on exercise
Single change of pressure at low level 0 2 saturation did not fall on exercise
780
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J. Thoracic and Cardiovas. Surg.
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Fig. 2.—Electrocardiogram of Case 7 shows severe changes of right ventricular hypertrophy.
Vol. 45, No. 6 June. 1963
ISOLATED I N F U N D I B U L A R STENOSIS
781
Fig. 3.—Chest roentgenogram of case of moderate severity.
Fig. 4.—Chest roentgenogram of an advanced case shows much right ventricular enlargement
782
SLADE
J. Thoracic and Cardiovas. Surg.
2. Absence of an ejection click. No click was heard in any of the cases reported here but, of course, a click is not heard in many cases of severe pulmonary valvular stenosis. 3. Absence of post-stenotic dilatation of the pulmonary artery on the chest roentgenogram. In none of these cases was there any post-stenotic dilatation shown on the chest films. But again post-stenotic dilatation is not an invariable finding with valvular stenosis. 4. A selective angiocardiogram will show the level of stenosis accurately (Fig. 6). The information obtained is also useful in planning the incision in the heart. 5. Cardiac catheterization. This is usually reliable but difficulty may be experienced if there is a very high infundibular stenosis with dilatation of the valve ring.
Fig. 5.—Catheter withdrawal tracing with intracardiac electrocardiographic electrode shows ventricular complexes in the infundibular zone.
Association With a Small Ventricular Septal Defect.—Before the condition was frequently operated upon under cardiopulmonary bypass, an associated ventricular septal defect (VSD) was not often reported. Thus Glover7 quoted 4 cases of patients treated by closed operation with no VSD. Brock6 had 12 patients, 6 treated by closed resection and 6 by resection under conventional hypothermia. A VSD was only noted in one of the fatal cases which came to post mortem. Swan and his co-workers12 reported cases of 8 patients operated upon under conventional hypothermia who had no evidence of any VSD. However, apart from "Williams and his associates16 who quote cases of 3 patients without VSD, all authors who have performed operations with cardiopulmonary bypass have found a high incidence of associated VSD. McGoon and Kirklin 8 found a VSD in 2 of their 3 cases. Vogelpoel and Schrire 3 found a VSD in 2 of 8 cases—Gerbode9 found a VSD in one of 2 cases, and Hoffman and his colleagues 1 ' one in both of their cases. In this series, a VSD was present in 7 of the 13 cases. The association of a small VSD with pulmonary valvular stenosis seems to be much less frequent. Gerbode9 noted only one small VSD in 29 cases of pulmonary valvular stenosis. In all reported cases, the VSD has been small, not more than 8 mm. in
Vol. 45, No. 6 June, 1963
ISOLATED I N F U N D I B U L A R STENOSIS
783
Pig. 6.—Angiocardiogram of Case 3 shows a large infundibular chamber.
Fig. 7.- -Heart of Case 7. The arrow shows the site of the small ventricular septal defect. The hypertrophy of the right ventricular muscle is also demonstrated.
SLADE
784
J. Thoracic and Cardiovas. Surg. TABLE
CASE NO.
SIZE OF INFUNDIBULAR STENOSIS
SITE OF S T E N O S I S AND SIZE OF I N FUNDIBULAR CHAMBER
SIZE OF VSD (MM.) —
POSITION OF VSD
IV.
P R E S S U R E S BEFORE OPERATION ( M M . H G ) PA
INF.
17/12
16/11
-
20/10
20/10 200/10
-
22/11
28/9
78/8
High Infra-CSV*
20/0
50/0
80/0
7x6
Under tricuspid valve
20/5
25/0
60/0
Low Large
3x3
Infra-CSV
20/2
50/0
170/0
0.75 cm. dia.
Fairly high Small
7x7
High Infra-CSV
12/0
12/0
158/0
8 P . G.
0.8 cm. dia.
Low Large
5x3
Under tricuspid valve
28/10
38/2
78/2
9 F . C.
0.6 cm. dia.
High Small
6x2
High Infra-CSV
24/8
-
172/6
10 T.Y.
0.5 cm. x 1.0 cm.
High Small
5x5
High Infra-CSV
5/0
75/0
100/0
11 M. D.
0.5 cm. dia.
High Very small
-
-
25/10
30/0
200/0
12 M. H.
0.6 cm. dia.
Medium Fairly large, 2 x 2 cm.
-
-
25/10
25/10 130/10
13 G. 0 .
1.0 cm. dia.
30/10
30/5
1 M.B.
0.5 cm. dia.
Low Fairly large
2 S. M.
0.6 cm. dia.
Low Large, 3 x 3 cm.
-
3 J . C.
0.75 cm. dia.
Low Very large
-
4 J. F .
0.75 cm. dia.
Medium Moderate size
3x4
5 G. S.
0.75 cm. dia.
Medium Moderate
6 R. P .
1.0 cm. dia.
7 K. E.
•CSV
High (2 cm. below valve ) Small Crista supraventricularis.
|
RV
80/10
120/5
diameter, and the infundibular stenosis is the important factor. As Hoffman and co-workers17 have suggested, it is probable that these small defects are not functional. In this series, two of the defects lay under the septal cusp of the tricuspid valve, the others were in the thickened muscle just under the crista supraventricularis and appeared to be at least partially closed during ventricular systole. Fig. 7 shows the heart of a patient of one of the fatal cases with the small VSD sutured. It is possible that shunting will occur as the right ventricular pressure falls and it is, therefore, advisable to close the VSD at operation.
785
ISOLATED I N F U N D I B U L A R STENOSIS
Vol. 45, N o . 6 June. 1963 OPERATIVE FINDINGS
PRESSURES AFTER OPERATION ( M M . H G ) INF.
RV
26/11
27/12
30/7
Transverse, through infundibulum
Good Still has pulmonary insufficiency
20/10
20/5
30/0
Transverse, through infundibulum
Good
25/15
27/9
27/9
Transverse, through infundibulum
Good
30/10
25/10
25/10
Vertical in RV
Good
Murmur abolished
16/5
16/5
20/4
Vertical in RV
Died 7th day
Abnormal coronary artery pattern
30/7
35/7
60/7
Transverse, in inf undibulum
Good
18/5
18/5
25/5
Vertical
Died
Muscle hypertrophy ++ Difficulty in suturing RV
24/13
30/4
34/5
Transverse, in infundibulum
Good
Murmur abolished
48/6
Transverse in RV
Good
Abnormal coronary artery pattern
18/6
OPERATIVE APPROACH
RESULTS
REMARKS
Pulmonary ring greatly dilated
15/0
25/0
50/0
Vertical in RV
Died 48 hr. postop.
Cardiac output in postop. poor; some possible cerebral complication
25/10
35/0
50/0
Vertical in RV
Died 30 hr. postop.
Cardiac output poor first few hours after operation
25/20
25/10
30/15
Vertical through RV & infundibulum
Good
30/5
Vertical in RV only
Good
30/15
Murmur abolished
Dye curves and oxygen saturations at cardiac catheterization have not proved helpful in showing up the VSD. Right ventricular and systemic pressures were separated by inhalations of amyl nitrite, whether a VSD was present or not. In 2 patients with an associated VSD, the oxygen saturation fell on exercise and, in one of these cases, amyl nitrite inhalations produced cyanosis, but these tests were not positive in other cases of associated VSD. In both of these cases, although the VSD was small it was less tucked away under the muscle mass of the crista supraventricularis than in the other cases reported here. Angiocardiograms taken at 6 frames a second did not shown up the defects, but in Case 9 a cine-angiocardiogram showed the VSD very nicely.
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J. Thoracic and Cardiovas. Surg.
TREATMENT
Operations were performed in 12 cases with the use of a Melrose type heart-lung machine and, in one case, with profound hypothermia by the Drew technique. Swan and his co-workers12 have obtained good results using conventional hypothermia but, with this method, operating time is limited and it may be argued that patients such as these, with greatly thickened ventricles, benefit from the support given by an extracorporeal circulation. In this series the deaths were due to cardiac failure in the early postoperative period. In all the cases reported here there was a localized stenosis of thick, white, fibro-endocardial tissue occurring at varying levels. The long stenotic infundibulum described by Lev11 was not encountered. As Blount and his associates5 have pointed out, the crista supraventricularis and its bands are usually abnormal and division of some part of the hypertrophied bands is often required as well as resection of the actual stenotic area. Grant and his co-workers,13 in their study of the architecture of the right ventricular muscle, suggest that defects in the inner layer give abnormal cristal bands and localized stenoses, whereas defects of the outer layer are likely to result in a VSD. Hence the association of the two conditions is theoretically a strong possibility and infundibular stenosis is only at one end of the spectrum of developmental abnormality of the musculature of the right ventricle which is represented in the most severe form by the tetralogy of Pallot. Brock10 has drawn attention to the fact that the hypertrophied muscle in this type of heart is unhealthy. Histological examination of the myocardium in a fatal case (No. 7) showed much fibrosis and hydropic degeneration of the sarcoplasm. A ventriculotomy will further impair the efficiency of the heart, and incisions in this type of heart muscle are often difficult to close. In Case 7 in this series, the ventriculotomy could only be closed after prolonged efforts and the use of Teflon patches. Where a good-sized infundibular chamber has been present, a transverse incision through the chamber has given good access, both for relief of the stenosis and repair of any VSD that is present. This incision was used in 5 cases and was always easy to close; it appeared to interfere very little with the action of the heart. However, when the stenosis is at a higher level, an approach through the right ventricle is necessary. A very real problem in these cases appears to be failure of cardiac output in the immediate postoperative period. Both March14 and Sanger 15 and their colleagues have demonstrated that transverse incisions interfere less with the function of the right ventricle than vertical incisions. In this series, in all the fatal cases there had been a vertical incision in the right ventricle. A further argument for the use of a transverse incision is that abnormally large branches of the right coronary artery are often crossing the outflow part of the right ventricle and may possibly be spared by a transverse ventriculotomy. Such arteries were present in 3 of the cases in this series. In all 7 cases, the small VSD was easily closed by direct suture.
Vol. 45, No. 6 June, 1963
ISOLATED I N F U N D I B U L A R STENOSIS
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RESULTS
Four patients died as a result of the operation. In 3 of these cases the cardiac output was never well maintained from the time of operation and death occurred within the first 48 hours. The fourth patient lived for 7 days and the course was complicated by severe postoperative hemorrhage, so that right ventricular failure cannot be held so directly responsible for the fatal outcome. The gradient across the stenosis was abolished at operation in 2 cases with fatal outcome and in the other cases a residual gradient of 15 and 25 mm. Hg remained. In the surviving cases the gradient was abolished in 4 cases and in the others remained from 10 to 30 mm. Hg. Inadequate relief of the stenosis does not appear to have played any part in the fatal outcome. The preoperative right ventricular pressures in the fatal instances were 100 mm. Hg, 125 mm. Hg, 170 mm. Hg, and 175 mm. Hg, so that this group contained 2 patients with the highest right ventricular pressures in the series. Long-standing obstruction undoubtedly causes severe damage to the right heart and surgical treatment may not be well tolerated. All the surviving patients have been followed up for a minimum of 6 months. None have any symptoms. In 3 cases the murmur has been abolished, and, in the remainder, the systolic murmur is short with the pulmonary element of the second heart sound audible although usually showing some delay. In all cases, the electrocardiogram has shown some regression of the changes of right ventricular hypertrophy. SUMMARY
Thirteen cases of isolated infundibular stenosis are reported. The physical signs and investigations are discussed. A small ventricular septal defect was present in 7 cases. Surgical treatment gave good results but there were 4 deaths. My thanks are due the physicians and surgeons under whose care these patients were treated—Drs. E. V. Gibson, 6 . W. Hayward, W. Oliver, and P . Wood, Sir B. C. Brock, Mr. W. P. Cleland, Mr. M. Paneth, and Mr. O. S. Tubbs. REFERENCES 1. Abbott, M.: Atlas of Congenital Heart Disease, New York, 1936, American Heart Association. 2. Campbell, M.: Simple Pulmonary Stenosis, Brit. Heart J . 16: 273, 1954. 3. Vogelpoel, L., and Schrire, V.: Auscultatory and Phonocardiographic Assessment of Pulmonary Stenosis, Circulation 22: 55, 1960. 4. Engle, M. A., Ito, T., Lucas, O. S., and Goldberg, H. P . : Electrocardiogram in Pulmonary Stenosis, J . Pediatrics 57: 171, 1960. 5. Blount, S. G., Vigoda, P . S., and Swan, H . : Isolated Infundibular Stenosis, Am. Heart ' J . 57: 684, 1959. 6. Brock, E. C.: Isolated Infundibular Stenosis in Advances in Cardiology, Basel/New York, 1959, S. Karger, vol. 2, p. 44. 7. Glover, B. P., O'Neill, T. J . E., Goantigo, H., McAuliffe, T. C , and Wells, C. E. E . : Surgery of Infundibular Pulmonary Stenosis, J . THORACIC SURG. 28: 481, 1954. 8. McGoon, D. C , and Kirklin, J . W . : Pulmonic Stenosis With Intact Ventricular Septum, Circulation 17: 180, 1958. 9. Gerbode, F., Eoss, J . K., Harkins, G. A., and Osborn, J . J . : Surgical Treatment of Pulmonic Stenosis Using Extracorporeal Circulation, Surgery 48: 58, 1960. 10. Brock, E. C : Surgical Treatment of Pulmonary Stenosis, Brit. Heart J . 23: 337, 1961.
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11. Lev, M.: Autopsy Diagnosis of Congenitally Deformed Hearts, Springfield, 111., 1953, Charles C Thomas, Publisher. 12. Swan, H., Hederman, W. P., Vigoda, P . S., and Blount, S. G., J r . : Surgical Treatment of Isolated Infundibular Stenosis, J . THORACIC SURG. 38: 319, 1959. 13. Grant, E. P., Downey, F . M., and MacMahon, H . : Architecture of Bight Ventricular Outflow Tract, Circulation 24: 223, 1961. 14. March, H. W., Boss, K. J., Weirich, W. L., and Gerbode, F . : Influence of Ventriculotomy Site on Contraction and Function of Right Ventricle, Circulation 24: 572, 1961. 15. Sanger, P . W., Bobicsek, F., Taylor, F . H., and Davis, S. C.: Method of Preventing Myocardial Damage by Using Modified Ventriculotomy Incision, Ann. Surg. 156: 874, 1962. 16. Williams, G. R., Richardson, W. R., Cayler, G. C , and Campbell, G. C.: Infundibular Pulmonic Stenosis With Intact Ventricular Septum, Am. Surgeon 27: 307, 1961. 17. Hoffman, J . I. E., Rudolph, A. M., Nadas, A. S., and Gross, R. E.: Pulmonic Stenosis, Ventricular Septal Defect, and Right Ventricular Pressure Above Systemic Level, Circulation 22: 405, 1960.