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To define the influence of ventriculo-coronary (VC) arterial connections on ventricular performance and late outcome, and associated wall motion abnormalities in patients with pulmonary atresia and intact ventricular septum, 21 patients aged [greater than or equal to 6 months (mean 4.3 [+ or -] 3.3 years, range 0.5 to 11.8) were reviewed. Ventricular volumes, mass, systolic functional variables and regional wall motion were measured using biplane ventricular cineangiography. Fourteen patients had VC connections, 11 of whom had coronary artery abnormalities. In comparing patients with VC connections and coronary abnormalities (group I) with those without coronary abnormalities (group II), no hemodynamic differences were observed, except the expected increased right-to-left ventricular systolic pressure ratio in group I (1.33 [+ or -] 0.24 vs 0.72 [+ or -] 0.50). Wall motion abnormalities were observed in 8 patients (7 in group I, and only 1 in group II [p Ventriculo-coronary (VC) arterial connections are clinically important and may be of prognostic significance in some infants with pulmonary atresia and intact ventricular septum.[1-3] These connections can be observed in more than half of these infants, particularly those with profound right ventricular hypoplasia, and may be associated with interruption or obstruction within the coronary vessels, resulting in a so-called right ventricular dependent coronary circulation, and contribute to myocardial ischemia.[1-4] In this regard, ventricular wall motion assessment may yield important information, helpful in following and managing this highly lethal anatomy, because most late deaths appear to be related to severe myocardial ischemia or infarction.[4,5] Although there are numerous studies examining the histopathologic characteristics and influences of VC connections on early clinical outcome,[1-7] little is known regarding influences on cardiac performance[8,9] and late outcome.[4,7] The present study evaluates the impact of VC connections (associated with coronary arterial abnormalities) on ventricular performance and late outcome, and the clinical implications of wall motion abnormalities in this unique patient group. METHODS Patients: From 1983 through 1991, 61 patients with pulmonary atresia with intact ventricular septum were observed, and from this cohort, 21 aged [greater than or equal to]6 months who had acceptable ventricular cineangiography for hemodynamic and wall motion analysis were reviewed retrospectively. There were 13 boys and 8 girls whose mean age at the time of the study was 4.3 [+ or -] 3.3 years (range 6 months to 11.8 years). All patients had [greater than or equal to]1 previous palliative surgery, including systemic-to-pulmonary shunts in 18, right ventricular outflow patch reconstruction in 5, pulmonary valvotomy in 2, thromboexclusion of the right ventricle in 5, caval-to-pulmonary shunts in 5, and a Blalock-Hanlon procedure in 2. No patient had Ebstein's anomaly of the tricuspid valve. All patients had a standard electrocardiogram before catheterization. Control subjects: Twenty-five children (3 male and 22 female; mean age of 4.1 [+ or -] 2.2 years, 1.4 to 9.3), who were undergoing cardiac catheterization and found to have hemodynamically insignificant lesions not affecting left ventricular volume and pressure variables, served as control subjects. Control subjects had a small ductus arteriosus (Qp/Qs Cardiac catheterization and angiographic studies: All patients underwent selective right ventriculography for assessing VC connections, and selective coronary angiography was performed if needed. Tricuspid valve diameter was based on the z-value concept advocated by Kirklin and Blackstone,[10] using data from Rowlatt et al.[11] Left ventricular mass and volumes were obtained from biplane cineventriculograms in the right anterior and axial left anterior oblique projections at 60 frames/ second, and the cavity borders were traced manually at end-diastole and end-systole during sinus rhythm. Ventricular end-diastolic and end-systolic volumes were calculated by a modified Simpson's rule, corrected by regression equations established in our laboratory,[12] and indexed for body surface area as end-diastolic and end-systolic volume indexes. Ventricular mass was calculated as previously described by Rackley et al[13] and indexed to body surface area (expressed as g/[m.sup.2]). Ejection fraction and heart rate-corrected mean normalized systolic ejection rate of the left ventricle were determined as systolic ejection phase parameters.[14] Regional wall motion was analyzed from a centerline method established by Sheehan et al.[15] In this technique, wall motion is determined clockwise from 100 chords drawn perpendicular to a centerline constructed midway between the end-diastolic and end-systolic counters. The length of each chord is normalized to yield a shortening fraction by dividing by the length of the end-diastolic perimeter. In this study, end-diastolic and end-systolic outlines were superimposed from the middle of the aorta and rotated until the lines from the center of mass to the middle of the aorta along the long axes were aligned.[16] Hypokinesia was defined as present when there were >10 consecutive contiguous chords whose shortening fraction differed by >2 SD below the mean shortening fraction of normal. Mitral valve (chords 75 to 100 in the right anterior and 1 to 25 in the axial left anterior oblique projections) and septal areas (chords 75 to 100 in the latter projection) were not included in the evaluation. Measurements were processed on an Angiographic Ventricular Dynamics System (Siemens-Elema AB Solna, Sweden). Statistical analysis: Data are expressed as mean [+ or -] 1 SD. Statistically significant differences among the 3 groups were determined by 1-way analysis of variance, followed by a Bonferroni method if the p value was RESULTS VC connections were observed in 14 patients, 11 of whom had apparent coronary abnormalities including interruption (n = 4) or significant stenosis ([greater than or equal to]75% of the luminal diameter; n = 3) of the left anterior descending artery in 7, interruption of the right coronary artery in 2, and significant stenosis of both coronary arteries ([greater than or equal to]75%) in 2. All patients with VC connections had a hypoplastic tricuspid valve (z value -3.1 [+ or -] 0.7), whereas in 3 of 7 without VC connections, tricuspid valve diameter was within normal or only slightly decreased (z value -0.6 [+ or -] 3.1) (p [TABULAR DATA I OMITTED] Wall motion abnormalities were observed in 8 patients (4 with anterolateral, 3 with apical and 1 with posterolateral hypokinesia) (Figure 1). Seven of 8 patients with abnormal wall motion were in group I, whereas only I was in group II (p [TABULAR DATA II OMITTED] Five patients died during follow-up, all of whom had wall motion abnormalities. The interval from catheterization to death was 7.6 [+ or -] 6.7 months (range 3 days to 1.3 years). Four of these patients had VC connections plus coronary abnormalities and died at the time of thromboexclusion of the right ventricle (n = 2) or suddenly (n = 2); the remaining child without VC connections died suddenly. DISCUSSION Ventriculo-coronary connections in pulmonary atresia and intact ventricular septum: Although recent surgical results in patients with pulmonary atresia and intact ventricular septum have improved,[7,17,18] the outcome for many patients with this disorder remains less than favorable.[4,17] In our institutional experience with this anomaly, the early mortality in the surgically treated group was 27% and actuarial survival only 25% at 13 years.[4] Several risk factors related to early mortality have been recognized, including a lower body weight at operation, decreased systolic pressure ratio between the right and left ventricles, and the presence of VC connections.[4] VC Connections have a predilection to the development of a fibrous intimal hyperplasia resulting in interruption or obstructive lesions in the native coronary circulation, and surgical decompression or exclusion of the right ventricle may lead to myocardial infarction in patients with a so-called right ventricular dependent coronary circulation.[1,4,17,19] Histopathologic study has revealed that a varying degree of intra- and extramural coronary arterial structural abnormalities are frequently observed in patients who die aged The present data support these previous observations and further demonstrate that patients with VC connections plus coronary abnormalities have a high incidence of wall motion abnormalities in long-term follow-up; Significantly increased ventricular volumes, mass and cardiac indexes were observed compared with those of control subjects, regardless of the presence of VC connections, reflecting in most patients (86%) a systemic-to-pulmonary shunt. However, mass/volume ratio in those patients remained within the normal range, suggesting that the increased volume and mass indexes were appropriately adapted, which is similar to findings observed in patients with univentricular connection to a dominant left ventricle before the Fontan procedure.[14] Wall motion abnormalities in pulmonary atresia and intact ventricular septum: In pediatric patients, there are limited studies of angiographic ventricular wall motion,[20,21] because of the complex ventricular topology and the need for established normal ranges. Although our 'normal' cohort was not without cardiac lesions, volumetric and hemodynamic variables from these subjects correlated closely with previous normal reports in children of this age,[22,23] suggesting that the associated cardiac lesions did not influence left ventricular function and wall motion. Patients with wall motion abnormalities had a decreased ejection fraction and increased ventricular systolic pressure ratio as compared with those with normal wall motion. Although we did not perform myocardial perfusion studies, and electrocardiographic ischemic changes were not observed in all patients with abnormal wall motion, 5 who had these abnormalities died during follow-up at the time of thromboexclusion of the right ventricle or suddenly, suggesting the presence of myocardial ischemia.[19] Because the normal range for wall motion in the newborn period is distinctly different from childhood,[24,25] and angiographic normals are not available, we could not assess wall motion in newborn patients. However, as suggested by the histopathologic findings, these myocardial ischemic changes are probably prenatal in onset, and the abnormal wall motion segments may be related to the ongoing myocardial ischemic changes. Methodologic limitations: The present patient cohort does not represent the entire spectrum of subjects undergoing evaluation and surgery. Some patients with large VC connections died and their data was not appropriate or adequate for this study, and in others, left ventriculography had not been performed. Thus, this hemodynamic evaluation reflects a selected patient cohort whose natural course may be less severe than that of the total population in this setting. In this regard, these subjects may represent the best patient outcome in respect to ventricular function. There are some limitations of the wall motion analysis in this setting. Left ventricular loading conditions differ according to the choice of palliative surgery (i.e., right ventricular outflow reconstruction may reduce left ventricular loading conditions in this setting, whereas systemic-to-pulmonary shunt further increases it). The suprasystemic right ventricular pressure induces the septal bulge and this may influence wall motion analysis. Although we attempted to exclude the septum within the measurements, compensatory changes in adjacent segments may have occurred. Furthermore, systemic ventricular hypertrophy or perioperative myocardial damage may influence these wall motion abnormalities.[21,26] Thus, these wall motion abnormalities are not merely an indicator of ischemia in this regard, but are probably of multifactorial origin. [1.] Freedom RM, Harrington DP. Contributions of intramyocardial sinusoids in pulmonary atresia and intact ventricular septum to a right-sided circular shunt. Br Heart J 1974;36:1061-1065. [2.] O'Connor WN, Cottrill CM, Johnson GL, Noonan JA, Todd EP. Pulmonary atresia with intact ventricular septum and ventriculocoronary communications: surgical significance. Circulation 1982;65:805-809. [3.] Gittenberger de Groot AC, Sauer U, Bindl L, Babic R, Essed CE, Buhlmeyer K. Competition of coronary arteries and ventriculocoronary arterial communications in pulmonary atresia with intact ventricular septum. Int J Cardiol 1988;18:243-258. [4.] Coles JG, Freedom RM, Lightfoot NE, Dasmahapatra HK, Williams WG, Trusher GA, Burrows PE. Long-term results in neonate with pulmonary atresia and intact ventricular septum. Ann Thorac Surg 1989;47:213-217. [5.] Fyfe DA, Edwards WD, Driscoll DJ. Myocardial ischemia in patients with pulmonary atresia and intact ventricular septum. J Am Coll Cardiol 1986;8:402-406. [6.] Koike K, Wilson GJ, Perrin DG, Freedom RM. Coronary artery involvement and myocardial ischemia in newborn babies less than one week old with pulmonary atresia and intact ventricular septum. In: Freedom RM, ed. Pulmonary Atresia with Intact Ventricular Septum. New York: Futura, 1989:101-107. [7.] Hawkins JA, Thorne JK, Boucek MM, Orsmond GS, Ruttenberg HD, Veasy LG, McGough EC. Early and late results in pulmonary atresia and intact ventricular septum. J Thorac Cardiovasc Surg 1990:100:492-497. [8.] Sideris EB, Olley PM, Spooner E, Farina M, Trusler G, Shaher R. Left ventricular function and compliance in pulmonaryatresia with intact ventricular septum. [9.] Hausdorf G, Gravinghoff L, Keck EW. Effects of persisting myocardial sinusoids on left ventricular performance in pulmonary atresia with intact ventricular septum. Eur Heart J 1987;8:291-296. [10.] Hanley FL, Sade RM, Blackstone EH, Kirklin JW, Freedom RM, Nanda NC. Outcomes in neonatal pulmonary atresia with intact ventricular septum: a multiinstitutional study. J Thorac Cardoivasc Surg 1993;105-406-427. [11.] Rowlatt UF, Rimoldi HJA, Lev M. The quantitative anatomy of the normal child's heart. Pediatr Clin North Am 1963;10:499-588. [12.] Ino T, benson LN, Mikalian H, Freedom RM, Rowe RD. Determination of left ventricular volumes by Simpson's rule in infants and children with congenital heart disease. Br Heart J 1989;61:182-185. [13.] Rackley CH, Dodge HT, Coble YD, Hay RE. A method of determining left ventricular mass in man. Circulation 1964;29:666-671. [14.] Akagi T, Benson LN, Green M, Gilday DL, Williams WG, Freedom RM. Ventricular performance before and after Fontan repair for univentricular atrioventricular connection: angiographic and radionuclide assessment. J Am Coll Cardiol 1992;20: 920-926. [15.] Sheehan FH, Bolson EL, Dodge HT, Mathey GD, Schofer J, Woo HW. Advantages and applications of the centerline method for characterizing regional ventricular function. Circulation 1986;74:293-305. [16.] Rickards A, Seabra-Gomes R, Thurston P. The assessment of regional abnormalities of the left ventricle by angiography. Eur J Cardiol 1977;167-182. [17.] Billingsley AM, Laks H, Boyce SW, George B, Santuli T, Williams RG. Definitive repair in patients with pulmonary atresia and intact ventricular septum. J Thorac Cardiovasc Surg 1989;97:746-754. [18.] McCaffrey FM, Leatherbury L, Moore HV. Pulmonary atresia and intact ventricular septum. Definitive repair in the neonatal period. J Thorac Cardiovasc Surg 1991;102:617-623. [19.] Williams WG, Burrows P, Freedom RM, Trusler GA, Coles JG, Moes CAF, Smallhorn J. Thromboexclusion of the right ventricle in children with pulmonary atresia and intact ventricular septum. J Thorac Cardiovasc Surg 1991;101:222-229. [20.] Gibson DG, Traill TA, Brown DJ. Abnormal ventricular function in patients with univentricular heart: cineangiographic study. Herz 1979;4:226-231. [21.] Penny DJ, Redington AN. Angiographic demonstration of incoordinate motion of the ventricular wall after the Fontan operation. Br Heart J 1991;66:456-459. [22.] Graham TPJ, Franklin RCG, Wyse RKH, Gooch V, Deanfield JE. Left ventricular wall stress and contractile function in childhood: normal values and comparison of Fontan repair versus palliation only in patients with tricuspid atresia. Circulation 1986;74(suppl I):I-61-I-69. [23.] Onnasch DGW, Lange PE, Heintzen PH. Left ventricular muscle volume in children and young adult. Pediatr Cardiol 1984;5:101-106. [24.] Rein AJJT, Sanders SP, Colan SD, Parness IA, Epstein M. Left ventricular mechanics in the normal newborn. Circulation 1987;76:1029-1036. [25.] Vogel M, Smallhorn JF, Stein JI, Freedom RM. Echocardiographic analysis of regional left ventricular wall motion in normal children and neonates. J Am Coll Cardiol 1990;15:1409-1416. [26.] Akagi T, Benson LN, Freedom RM. Regional ventricular wall motion abnormalities in tricuspid atresia after the Fontan procedure. J Am Coll Cardiol 1993;in press. From the Departments of Pediatrics and Surgery, Divisions of Cardiology and Cardiovascular Surgery, the Variety Club Cardiac Catheterization Laboratories, Hospital for Sick Children, Toronto, Ontario, Canada. Dr. Akagi's work was supported by a grant from Heart and Stroke Foundation of Canada Research Fellowship, the Ontario Heart and Stroke Foundation, Toronto, Ontario, Canada. Manuscript received June 26, 1992; revised manuscript received May 3, 1993, and accepted May 10. Address for reprints: Lee N. Benson, MD, Division of Cardiology, Hospital for Sick Children, 555 University Avenue, Toronto, Ontario, Canada M5G 1 X8.

The value of the cava-pulmonary anastomosis (Glenn procedure) was assessed by reviewing the entire experience with this procedure in 83 children at The Hospital for Sick Children, Toronto, from 1961 to 1980. The over-all operative mortality rate was 9.6%, but only 2% in the second half of the series. The average follow-up is 9.4 years per patient. The late mortality rate has been 20%. By actuarial analysis, 84% of survivors were alive 9 years after operation; 54% had adequate palliation and 46% had required further operation. Long-term palliation was significantly better when the anastomosis was performed after 5 years of age. A previous arterial pulmonary artery shunt had no effect on either patient or shunt survival. Patients with tricuspid atresia had a better long-term survival rate than, but similar shunt survival to, those children with transposition, single ventricle, or miscellaneous cardiac anomalies. Angiography in 36 survivors showed patent shunts in 35 and no arteriovenous fistulas. Clinical status was not related to superior vena caval pressure or angiographic findings, indicating that Glenn shunt failure is a functional problem. The procedure is most useful for patients over 5 years of age who have complex heart disease not amenable to total repair. It is also an appropriate initial procedure in young patients over 18 months of age for whom direct atrium-pulmonary artery anastomosis is proposed as the future definitive treatment.

Two hundred nine children with congenital heart defects characterized by excessive pulmonary blood flow underwent pulmonary artery banding at The Hospital for Sick Children from January, 1972, through December, 1982. The indications for banding, rather than complete repair, varied with the type of cardiac defect as well as with the year of presentation to our hospital A simplified method of estimating required band circumference has been developed for infants with ventricular septal defect, with or without major intracardiac mixing disorders. Infants with simple defects without intracardiac bidirectional mixing disorders receive a band at a circumference of 20 mm + 1 mm for each kilogram of body weight, whereas infants with bidirectional mixing disorders receive a band at a circumference of 24 mm + 1 mm for each kilogram of body weight. The overall operative mortality varies with the underlying cardiac defect and with associated medical conditions but is relatively low in the less-complicated cases. The use of a formula to predict a starting band circumference, with loosening only as required by cyanosis or bradycardia, allows predictable control of congestive symptoms and pulmonary hypertension in the majority of infants. The cumbersome measurement of pulmonary artery pressure and the unpredictable changes in pressure during anesthesia are avoided. Pulmonary artery banding remains an effective means of achieving satisfactory palliation in infants with congenital heart disease and excessive pulmonary blood flow.

Postoperative low cardiac output is the most common cause of death in patients undergoing elective repair of tetralogy of Fallot. The incidence is much higher than in elective adult bypass operations for coronary artery disease. To explain this difference, we investigated 16 children having elective repair of tetralogy (mean age 6.3 years). Myocardial biopsy specimens obtained during bypass before arrest, at the end of cold arrest by blood cardioplegia, and after 30 minutes of reperfusion were studied for adenosine triphosphate and lactate levels. Myocardium was submitted for microscopic study shortly after the onset of ischemia. The operation was successful in reducing right ventricular -pulmonary artery gradients from 82 ± 28 to 9 ± 1 mm Hg, yet seven patients required significant inotropic support (dopamine, >5 μg/kg/min) for more than 24 hours and 12 patients needed prolonged use of digoxin and diuretics for right ventricular failure. Tissue levels of adenosine triphosphate and lactate in the tetralogy groups were compared with those in 20 adults with coronary artery disease having similar myocardial protection techniques. Adenosine triphosphate levels in the tetralogy group decreased during cross-clamping (41 ± 8 minutes) from 24 ± 3 to 16 ± 2 mmol/kg dry weight (mean ± 1 standard error), with a marked further drop after reperfusion to 9 ± 2 mmol/kg (p < 0.01). Adenosine triphosphate levels in the group with coronary disease also decreased from 20 ± 1 to 16 ± 1 mmol/kg after a longer cross-clamp time (70 ± 17 minutes) but remained at 15 ± 2 mmol/kg after reperfusion. Tissue lactate levels in the tetralogy group rose markedly during ischemia and remained elevated after reperfusion. In contrast, lactate levels in the group with coronary disease rose moderately during ischemia and returned to normal early on reperfusion. Microscopic study revealed focal myocyte necrosis in tetralogy of Fallot. Our findings, which demonstrate inadequate myocardial protection of patients with tetralogy during repair, with depression of adenosine triphosphate and increased lactate during ischemia and reperfusion, suggest a defect in oxidative metabolism. The drop in adenosine triphosphate after reperfusion in the patients with tetralogy implicates reperfusion injury as a mechanism of myocardial damage.

• We review innominate artery compression of the trachea in 60 surgically corrected patients and 30 in patients who did not undergo surgery. The symptoms and radiologic features are correlated with the degree of tracheal narrowing at bronchoscopy and with associated defects that may exist. From this study, a history of respiratory distress with "reflex apnea" associated with tracheal narrowing is a strong indication for surgery. Stridor and recurrent respiratory infections are not an indication in themselves, and must be assessed with the severity of tracheal narrowing and presence or absence of associated defects. Surgery resulted in complete or moderate relief in most patients, although the results were less gratifying when subglottic stenosis or a repaired tracheoesophageal fistula existed.(Arch Otolaryngol 101:733-738, 1975)

From December, 1977, through June, 1981, 15 patients with pulmonary atresia, ventricular septal defect, and hypoplastic pulmonary arteries underwent a palliative right ventricular outflow tract construction. In seven (Group A) this was the first surgical procedure, whereas in the remaining eight (Group B) previous systemic-pulmonary artery anastomoses had been performed. A high morbidity of the pulmonary arteries was present in Group B, resulting in part from the previous shunting procedures. The left pulmonary artery was severely hypoplastic in five patients; the right was hypoplastic in seven of the eight patients and was severely stenotic or atretic in three. All the patients in Group A survived the palliative right ventricular outflow tract reconstruction, and only one in Group B died. Almost all patients had an increase in the aortic Po2and oxygen saturations after palliative right ventricular outflow tract construction, with a concomitant fall in hemoglobin concentration. Three of the five patients in Group A who underwent postoperative angiography were found to have proximal left pulmonary artery stenosis, and three had lesser involvement of the proximal right pulmonary artery as well. Three of the six patients in Group B who were studied postoperatively also had severe stenosis or proximal atresia of the right pulmonary artery, and three patients had stenosis and hypoplasia of the left pulmonary artery as well, two severe. Thus in no patient in this series were normal pulmonary arteries achieved by palliative right ventricular outflow tract construction. It is unclear from our experience whether palliative right ventricular outflow tract construction will provide the potential for ultimate complete repair. The rather constant finding of severe proximal left pulmonary artery stenosis and hypoplasia in Group A is disappointing.

Seventeen patients with a univentricular atrioventricular connection and subaortic stenosis at the outlet foramen level were seen from 1974 until 1983. The ventricular anatomy was of a single left ventricle with an outlet chamber, and the great arteries were transposed. This condition often followed pulmonary artery banding (15 cases) but also occurred with pulmonic stenosis (one) or pulmonary atresia (one). The median interval to the detection of subaortic stenosis after banding was 2.3 years (range 11 days to 15 years). Thirteen patients had a resting gradient to 118 mm Hg and three a gradient only with isoprenaline infusion. The following surgical procedures have been performed: (1) insertion of a conduit between the left ventricle and aorta (one patient); (2) creation of an aorticopulmonary window proximal to the band and tightening of the band (three patients); (3) enlargement of the ventricular septal defect (three patients); (4) Fontan procedure (five patients); and (5) Fontan procedure plus arterial switch (two patients). All of the procedures but the last one have met with significant mortality in tins difficult group of patients.

Between June, 1977, and December, 1982, 106 infants underwent subclavian flap arterioplasty for repair of coarctation of the aorta in the first year of life. This technique was utilized because of our previous experience with the end-to-end technique in 181 infants, in whom there was a recurrence rate of 42% at 5 years. The recurrence rate in 78 of the 81 survivors who have been followed up for a mean of 18.8 months ± 15.9 months (standard error) is 17.3% at 1 year and 11.1% at 2 and 3 years postoperatively. The presence of associated disease affects mortality: only one death in 34 patients with isolated coarctation; three deaths in 24 with coarctation plus ventricular septal defect; and 21 deaths in 45 infants with coarctation and complex lesions. Our present approach in the group with coarctation plus ventricular septal defect is to repair the coarctation without banding the pulmonary artery and then to close the defect if the infant remains in failure. Operative survival was 13 of 13 without pulmonary artery banding and 11 of 14 with pulmonary artery banding.

Polytetrafluoroethylene tubular grafts are useful in performing a systemic–to–pulmonary artery shunt (modified Blalock-Taussig). They allow a controlled-volume shunt, avoid kinking of the pulmonary artery, and preserve distal flow in the subclavian artery. Unfortunately, occasionally excessive serous fluid will drain through the interstices of the fabric. This results in excessive and prolonged chest tube drainage and/or localized seroma formation around the graft This complication occurred in 26 children, an incidence of 18.8% of the 138 modified Blalock-Taussig operations. Repeat thoracotomy was required in four of these children—for evacuation of seroma mass in three and for relief of cardiac tamponade in one. Four other children required reinsertion of pleural or pericardial chest drains for excessive serous drainage persisting as long as 6 weeks after operation. Wrapping of the graft with silicone sheeting to facilitate subsequent takedown of the shunt led to seroma formation in five of nine children. We believe this practice should be abandoned. Excessive drainage of serous fluid through the interstices of PTFE grafts in almost 20% of our patients has compromised an otherwise satisfactory result of the modified Blalock-Taussig operation.

Ninety-two children underwent aortic (AVR) or mitral valve replacement (MVR), or both, at The Hospital for Sick Children in Toronto from 1963 to February, 1980. No early or late deaths occurred in 39 children having AVR. However, in 50 children having MVR, the operative mortality was 32% and the actuarial survival rate 5 years after operation was only 50%. Major complications occurred with almost equal frequency in the two groups; 50% of children surviving AVR or MVR experienced major complications within 6 years of operation. Retrospective comparison of results with tissue and mechanical valves showed no clear advantage with either type of prosthesis. Outgrowth of a prosthetic valve was satisfactorily managed in children with AVR but presented a difficult problem in those with MVR, who required frequent reoperation to increase the prosthetic valve to adult size. Prosthetic valve replacement in children is a palliative procedure at best, and every effort should be made to preserve the natural valve by a more conservative repair technique.

Left-sided juxtaposition of the right atrial appendage (LJRAA) was seen in 10 patients in a series of 361 consecutive Mustard procedures for transposition of the great arteries (TGA). Dextrocardia complicated LJRAA in four cases. Right atrial capacity and free atrial wall size were smaller than normal in all patients, and a Mustard intra-atrial baffle repair was performed in all instances. Direct caval cannulation or cannulation of either atrial appendage facilitated intra-atrial repair. Nine patients in whom the pulmonary venous atrium was enlarged with a patch survived. One child who did not have a right atrial patch died 1 hour postoperatively of pulmonary edema. Two late deaths occurred 1 year postoperatively. Seven children survived and are well. In one child, superior vena caval baffle obstruction is controlled by digoxin and diuretic therapy. TGA associated with juxtaposition of the atrial appendages (JAA) and dextrocardia may be successfully repaired by the Mustard procedure, provided that the tricuspid valve and right ventricle are normal, an adequate superior vena caval channel is created, and patch enlargement of the pulmonary venous atrium is undertaken.

Phrenic nerve paralysis was diagnosed in 125 children (1.6%) from a series of 7,670 cardiac surgical procedures in infants and children during a 12 year period. The incidence was 1.9% for open heart and 1.3% for closed heart operations. In order of decreasing incidence, the open heart procedures included Mustard procedure (6.7%), right ventricular outflow tract reconstruction (5.6%), and repair of tetralogy of Fallot (2.7%). The closed heart procedures included Glenn anastomosis (6.2%), Blalock-Hanlon atrial septectomy (5.9%), and right Blalock-Taussig shunt (5.1%). Procedures following previous operations or thoracotomies had almost twice the incidence of phrenic nerve paralysis: Mustard procedure 9.9%, right ventricular outflow tract reconstruction 10.8%, and tetralogy repair 5.5%. Seven patients (5.6%) with phrenic nerve paralysis died. Patients less than 2 years old with phrenic nerve paralysis were intubated for 0 to 57 (average 15.7) days after their cardiac operations and those over 2 years old for 13 to 35 (average 7.2) days (p < 0.001). Twelve patients had diaphragmatic plication without mortality and were extubated 0 to 6 (average 2.3) days after plication. We have made the following conclusions: (1) Phrenic nerve paralysis may occur after both open and closed cardiac procedures and is more common in children requiring reoperation; (2) it is associated with considerable morbidity; (3) eventual recovery of phrenic nerve function occurs in 84% of children; and (4) diaphragmatic plication is safe, reliable, and of most value in patients who are under 2 years of age and require mechanical ventilation for more than 2 weeks.

Clinical experience indicates that the risk of reparative cardiac operations is increased in the neonatal period relative to that in older infants and children. Age-related differences in the susceptibility to myocardial ischemic dysfunction were evaluated by comparison of left ventricular function and metabolism in neonatal (mean age = 7 days) and weanling (mean age = 96 days) piglets. Six animals in each group supported on cardiopulmonary bypass were subjected to (1) 120 minutes of hypothermic crystalloid cardioplegic arrest (CP-120) and (2) 15 minutes of normothermic ischemic arrest (NA-15) after a 60 minute interval of reperfusion. Left ventricular systolic and diastolic function was measured after each intervention via endocardially implanted ultrasonic dimension crystals in a septolateral minor-axis position. In both groups, systolic dysfunction was evidenced by an increase in the dimension-axis intercept (p = 0.001), but not the slope of the end-systolic pressure-dimension relation. Left ventricular end-diastolic stiffness, expressed as left ventricular end-diastolic pressure versus Lagrangian strain, increased to a similar degree in both groups (p = 0.001). Adenosine triphosphate levels declined significantly (p = 0.001) in both groups in response to the ischemic interventions with no evident intergroup differences. Lactate levels increased significantly during the course of the experiment (p = 0.04); however, the increases were greater (p = 0.009) at all intervals in the neonatal group. This study demonstrates age-related metabolic differences in response to ischemia consistent with a greater dependence on glycolysis in neonatal myocardia. However, the fact that discriminating age-related differences in left ventricular function were not evident suggests that factors other than young age per se account for the increased surgical mortality in the neonatal period.

The factors associated with survival in 40 neonates (age < 28 days) with critical aortic stenosis undergoing either open (22 patients) or closed (18 patients) transventricular aortic valvotomy were reviewed. Significant adverse correlates with survival included evidence of poor perfusion preoperatively (low pH, > Grade 2/6 soft ejection systolic murmur) and marked congestive heart failure (hepatomegaly, cardiomegaly, elevated left atrial pressure). Congenital mitral stenosis (anulus < 11 mm), a small aortic anulus (<6.5 mm), and failure to achieve an adequate aortic orifice (>6 mm), at operation were identified as factors associated with increased mortality. Initial perioperative survival was better with closed aortic valvotomy. However, there was no significant difference in overall operative survival between closed (9/18, 50%) and open (8/22, 36%) aortic valvotomy (p = 0.26). The incidence of early reoperation (<1 year of age) was greater in perioperative survivors undergoing closed valvotomy (7/13, 54%) rather than open valvotomy (1/10, 10%) (p < 0.05). In conclusion, long-term survival among patients with critical neonatal aortic valve stenosis remains disturbingly low (13/40, 32%) and has not significantly improved over the past 20 years.

Left ventricular systolic function and compliance were assessed in 15 cases of pulmonary atresia with intact ventricular septum. The left ventricular ejection fraction measured from cineangiography was used for the evaluation of the systolic function. The end-diastolic pressure (EDP), left ventricular compliance index at end-diastole (dv/dp), and left ventricular stiffness constant K were used as compliance indices. The mean left ventricular ejection fraction was slightly diminished. The right ventricular end diastolic pressures (RVEDPs) correlated significantly (r = 0.90) with the left ventricular end diastolic pressure (LVEDP). On the basis of left ventricular compliance, two distinctive groups of patients could be identified: Group I consisted of Patients 1 to 7, all with impaired left ventricular compliance. A shunt operation was the basic palliation in this group. None of these patients survived infancy. Group II consisted of Patients 8 to 15, all with normal left ventricular compliance. Pulmonary valvotomy as well as aortopulmonary shunts were the basic palliative procedures in this group. Six of eight patients in this group are long-term survivors. No difference was found in right ventricular size, tricuspid valve size, presence of tricuspid insufficiency, presence of a patent ductus arteriosus, postoperative oxygen saturations, and atrial pressure gradients between the two groups. Evaluation of the left ventricular compliance in patients with pulmonary atresia and intact ventricular septum might be of significant prognostic value for their early survival.

Inferences: A treatment protocol for patients with simple transposition, consisting of initial balloon atrial septostomy and leading to a delayed atrial switch repair of the Mustard type, in good circumstances, results in survivorship at 1 month, 1 year, 10 years, and 20 years of 95% (95% confidence limits [CL] 90% to 97%), 90% (95% CL 84% to 94%), 83% (95% CL 74% to 90%), and 80% (95% CL 70% to 88%), respectively. Low birth weight adversely affects survivorship. Hypoxia or heart failure accounts for most deaths within the first month and before the atrial switch (Mustard) repair. Most of the few deaths late postoperatively are sudden and they appear to occur particularly in patients who have junctional rhythm. A progressive increase in the prevalence of junctional rhythm has been a risk of the atrial switch repair, and only 76%, 65%, 59%, 56%, and 53% of patients can be expected to be free of this by 1, 5, 10, 15, and 20 years after repair. Important right ventricular dysfunction late after an atrial switch repair, with its adverse affect on the patients’ functional capacity, appears to be present in up to 10% of patients after the atrial switch repair, but may not be an immutable risk of this type of repair. About 90% of patients, essentially all of those who do not have right ventricular dysfunction, can be expected to be in New York Heart Association class I or II late postoperatively.