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Objective. Hypoplastic left heart syndrome (HLHS) is a relatively common complex congenital heart defect. Prior to development of staged reconstruction (i.e., Norwood procedure), HLHS was almost universally fatal within months of birth. Early survivors of the Norwood procedure are now reaching reproductive age. We report successful pregnancies in two such women. Patients. The first patient was a 20-year-old woman transferred from a community hospital at 33 3/7 weeks gestation because of preterm labor, suspected preeclampsia, and mild chronic hypoxemia. She had normal systemic ventricular shortening without significant valvar regurgitation but severe neoaortic dilatation. A fetal ultrasound demonstrated intrauterine growth restriction. An urgent Cesarean section was performed at 33 6/7 weeks gestation, given breech position and intractable preterm labor. The second patient, a 23-year-old woman followed at this institution through pregnancy, presented with preterm labor at 36 weeks gestation. Her systemic ventricular shortening was normal, with mild tricuspid regurgitation but without neoaortic dilation or regurgitation. She developed active labor at 36 3/6 weeks, and had a spontaneous vaginal delivery of a small for gestational age infant. Both women tolerated labor and childbirth without complication. Neither infant had evidence of structural heart disease on fetal echocardiography or physical examination. Conclusions. These cases, the first reported successful pregnancies in mothers with HLHS, highlight the challenges of pregnancy among women with complex congenital heart disease in general and raise several considerations specific to HLHS.

Background Despite significant improvement in survival after stage 1 Norwood, interim mortality before the second-stage operation remains significant. On the basis of reports of improved circulatory stability associated with the use of a right ventricle to pulmonary artery conduit, the difference between two physiologically different sources of pulmonary blood flow on interim mortality was investigated. Methods Data collection of 96 consecutive hospital survivors after stage 1 Norwood surgery was undertaken. The source of pulmonary blood flow was a modified right Blalock-Taussig shunt in 46 (BTS) and a right ventricle to pulmonary artery conduit in 50 patients. The same follow-up protocol was used in both groups. Data analysis was performed to identify variables associated with interim mortality. Results Analysis of patient-related and procedure-related variables revealed no differences in age, weight, diagnosis, presence of aortic atresia, lowest perioperative pH, duration of cardiopulmonary bypass, circulatory arrest, length of mechanical ventilation, or hospital stay at the time of stage 1 Norwood between groups. Respiratory rate and systolic blood pressure were the only differences detected between groups at the time of discharge. Interim mortality was higher in the Blalock-Taussig shunt group. Statistical analysis identified aortic atresia, a modified Blalock-Taussig shunt, and the presence of perioperative dysrhythmias to be associated with interim mortality. Conclusions The use of a right ventricle to pulmonary artery shunt decreases the incidence of interim mortality among hospital survivors after stage 1 Norwood for hypoplastic left heart syndrome. Aortic atresia, the use of a modified Blalock-Taussig shunt, and perioperative dysrhythmias are independently associated with a higher mortality before superior cavopulmonary connection.

Objective. To identify pre- and intraoperative variables associated with postoperative acute neurologic events (ANEs), including seizures and coma, in newborn survivors of congenital heart surgery undergoing deep hypothermic circulatory arrest (DHCA), and to risk-stratify this population on the basis of preoperative risk variables for the purpose of designing future neuroprotection trials. Methods. Survivors of newborn heart surgery who were enrolled in a neuroprotection trial provided a comprehensive database for the evaluation of pre- and intraoperative variables that influence the postoperative occurrence of ANEs (seizures or coma). Patients with hypoplastic heart syndrome were excluded. After characterization of the study population, stepwise logistic regression, combined with clinical judgment, was used to identify variables that were most likely to be associated with an increased risk of seizures in the study sample and that were most likely to be generalized to other populations. Results. Data were available on 164 nonhypoplastic left heart syndrome survivors who underwent newborn heart surgery using DHCA. ANEs occurred in 31 (18.9%) including “seizures alone” (n = 28), “coma alone” (n = 2) or “seizures and coma” (n = 1). A preoperative risk model was constructed demonstrating that infants with a genetic condition and aortic arch obstruction had a 47.8% risk of ANEs compared with all other remaining infants, who had a 9.9% risk. It was also found that prolonged DHCA time (≥60 minutes) can be a significant risk for infants who have a preexisting genetic condition; however, infants who have genetic conditions and do not undergo prolonged DHCA time or have an aortic arch obstruction are not at increased risk of ANEs. Conclusions. This study provides new information about the occurrence of ANEs after newborn heart surgery. Seizures or coma, which appeared in approximately 19% of all non–hypoplastic left heart syndrome survivors, were not random events but were significantly associated with specific types of congenital heart disease, the presence of genetic conditions, and prolonged DHCA time. The 3 identified variables permitted individual cases to be assigned to low-, intermediate-, or high-risk categories. Because neonatal seizures are a good surrogate marker of long-term neurologic outcome, these models provide useful information to stratify individual patients for risk of seizures in future neuroprotection trials.

Objective: Although the outcome of cardiac surgery in neonates with low birth weight (LBW) has improved, LBW remains a risk factor for surgical palliation. Few surgical series of LBW patients include those with hypoplastic left heart syndrome (HLHS). To identify variables associated with poor outcome in this group, we reviewed our experience with patients with HLHS and LBW who underwent Stage I Norwood palliation. Methods: Between January 1998 and December 2000, 20 consecutive LBW (,2500 g) neonates with HLHS ðn ¼ 13Þ or HLHS variant ðn ¼ 7Þ underwent surgical palliation. Retrospective review of all patient data and analysis to identify risk factors was performed. Results: Mean age at surgery was 5.1 ^ 4.6 days (range 1–17), mean weight was 1.98 ^ 0.44 kg (range 1.1–2.5), including nine patients under 2 kg. Ten patients were born at ,35 weeks gestation. Anatomic diagnosis included HLHS in 13 patients (10 with aortic atresia), unbalanced atrioventricular canal defect in two, double outlet right ventricle in two and other variants in three. Mean ascending aortic size was 4.0 ^ 1.8 mm (range 1.5–8). Associated cardiac defects were present in three patients, and a genetic syndrome and/or congenital anomaly was present in four of them. Mean circulatory arrest time was 60 ^ 10 min. Extracorporeal support was used perioperatively in 10 patients. Early mortality was 9/20 (45%). At a mean follow up at 22 ^ 10 months (range 8–38), six patients underwent stage II, and are awaiting stage III; four patients have completed their Fontan. Anatomic variant, ascending aortic size, prematurity, age at surgery, weight, duration of circulatory arrest, cardiopulmonary bypass time and associated non-cardiac anomalies were not risk factors for poor outcome whereas restrictive pulmonary venous drainage and coronary artery anomalies were associated with decreased survival. Conclusion: LBW newborns with HLHS and physiologic variants have an increased early surgical risk but have acceptable intermediate survival rates for subsequent palliation including Fontan. LBW and prematurity should not be contraindications to early surgical palliation. q 2002 Elsevier Science B.V. All rights reserved.

Objective: Thyroid hormone has important effects on cardiovascular performance. This study was performed to evaluate the changes in levels of triiodothyronine following the first stage of reconstruction for hypoplastic left heart syndrome. Methods: We enrolled 14 newborns with hypoplastic left heart syndrome scheduled for first stage reconstruction. Blood samples were obtained pre-, intra-, and post-operatively. Levels of free and total triiodothyronine were determined by radioimmunoassay. Statistical comparison was performed using Wilcoxon's signed rank test. Results: The levels of free triiodothyronine decreased from a baseline of 355 ± 31 pg/dl to 205 ± 21 pg/dl upon the institution of bypass, and declined to a level of 135 ± 9 pg/dl at 24 hours postoperatively. Similarly, levels of total triiodothyronine decreased from 101 ± 15 ng/dl to 65 ± 4 ng/dl upon the institution of bypass, and continued to decline during the first 24 hours postoperatively. Levels of free and total triiodothyronine had returned to baseline by the fifth postoperative day. Conclusions: The data demonstrate significant decreases in levels of free and total triiodothyronine during the early postoperative period. These changes in levels of thyroid hormone may have adverse effects on cardiac function during this phase of recovery.

Perfusion lung scans were performed immediately prior to Fontan procedure in 45 patients with a functional single ventricle who underwent the hemi-Fontan procedure as an intermediate stage between the initial palliative shunt procedure and the final complete Fontan anastomosis. Symmetric pulmonary blood flow (PBF) distribution was found in 27% of patients, whereas moderately to severely abnormal PBF distribution was found in 35% of patients. The achieved systemic aortic saturation following the hemi-Fontan procedure was not affected by these abnormalities.

Background. In hearts with a functional single ventricle, cavity volume and myocardial muscle mass increase as a consequence of the excessive volume work associated with parallel pulmonary and systemic circulations. The hemi-Fontan operation was conceived as a means of accomplishing early reduction of the volume work of the single ventricle. Methods. All patients presenting in infancy with single-ventricle physiology were managed by early hemiFontan operation in anticipation of a subsequent completion Fontan operation. Between May 1989 and August 1995, 400 patients less than 2 years of age underwent hemi-Fontan operations. Mean age at operation was 8.5 months (range, 2 months to 24 months). The hemi-Fontan operation included association of superior vena(e) cava(e) with the branch pulmonary arteries, augmentation of the central pulmonary arteries, occlusion of the inflow of the superior vena cava into the right atrium, and elimination of other sources of pulmonary blood flow. Results. Operative mortality ( Conclusions. The hemi-Fontan operation can be accomplished with low operative mortality in young patients, achieving early reduction of the volume work of the single-ventricle heart.

Excessive pulmonary overcirculation related to imbalance in the pulmonary/systemic vascular resistance ratio contributes to hemodynamic instability in infants with the hypoplastic left heart syndrome. Because the ductus arteriosus bridges the two vascular circuits in this lesion, we studied the Doppler echocardiographic flow patterns in the ductus arteriosus of 50 infants with hypoplastic left heart syndrome to investigate their relationship to the degree of pulmonary blood flow as measured by simultaneously obtained levels of partial pressure of oxygen in arterial blood. The degree of restriction to pulmonary venous egress as determined by size of the interatrial communication was also correlated with ductal flow patterns and partial pressure of oxygen in arterial blood. Biphasic flow was noted in all infants. Mean peak velocity of antegrade flow (pulmonary artery to aorta) was greater than that of retrograde flow (aorta to pulmonary artery) (131 +/- 45 cm/sec versus 54 +/- 15 cm/sec; p0.001), mean time of retrograde flow was greater than that of antegrade flow (246 +/- 60 msec versus 174 +/- 28 msec; p0.001), and mean velocity-time integral of antegrade flow was greater than that of retrograde flow (13.3 +/- 4.8 cm versus 6.3 +/- 3.4 cm; p0.001). The ratio of velocity-time integral of retrograde flow/antegrade flow (a volumetric estimate of diastolic reversal into the pulmonary vascular bed indexed to systemic output) correlated extremely well with partial pressure of oxygen in arterial blood (r = 0.91; p0.0001). Categoric size of the interatrial communication (none, n = 2; small [2 mm], n = 9; moderate [3 to 4 mm], n = 23; and large [4 mm], n = 16) correlated with partial pressure of oxygen in arterial blood (r = 0.82; p0.001); the smaller the interatrial communication the lower the partial pressure of oxygen in arterial blood and velocity-time integral ratio of retrograde/antegrade flow. Doppler flow patterns in the ductus arteriosus of infants with hypoplastic left heart syndrome are reflective of the resistance ratio between the pulmonary and systemic vascular circuits and may be helpful in monitoring the hemodynamics of these infants.

Background. After surgical removal of a volume load, regression of myocardial mass proceeds slowly relative to diminution in ventricular cavity size, resulting in increased wall thickness and decreased cavity dimensions, which may affect the filling properties and performance of the heart. We investigated the acute changes in ventricular geometry that occur after the Fontan operation and hemi-Fontan operation for tricuspid atresia, and compared them with closure of a ventricular septal defect in a two-ventricle heart. Methods. We reviewed the results of echocardiography performed before and 8 ± 7 days after (1) Fontan operation for tricuspid atresia (n = 9), (2) hemi-Fontan operation for tricuspid atresia (n = 10), and (3) closure of a ventricular septal defect (n = 13). Measurements were made from images of the left ventricle at end-diastole: (1) apical, septal, and posterior wall thickness; and (2) long- and short-axis cavity diameters, cross-sectional areas, and ventricular volume. Posterior wall thickness to cavity dimension ratio was calculated. Results. Wall thickness increased in all groups, with the greatest degree of increase after the Fontan operation. Cavity measures decreased most dramatically after the Fontan operation, with less dramatic and equivalent changes noted after the hemi-Fontan operation and ventricular septal defect closure. Posterior wall thickness to cavity diameter ratios were equivalent in all before operation, increased after operation, and were greatest after the Fontan operation. Conclusions. Changes in ventricular geometry identified as an increase in wall thickness and a decrease in cavity dimension are most dramatic after the Fontan operation. Changes seen after the hemi-Fontan operation are of a milder degree, which may in part explain the excellent clinical course after this operation.

Norwood's operation provides satisfactory palliation for neonates with hypoplastic left heart syndrome. The dominant physiologic features of hypoplastic left heart syndrome, ductal dependency of the systemic circulation and parallel pulmonary and systemic circulations, are shared by a multitude of other less common congenital heart malformations. Theoretically, these should be equally amenable to palliation by Norwood's operation. Between January 1990 and June 1994, 60 neonates with malformations other than hypoplastic left heart syndrome underwent initial surgical palliation by Norwood's procedure. Diagnoses included single left ventricle with levo-transposition of the great arteries (12); critical aortic stenosis (8); complex double-outlet right ventricle (8); interrupted aortic arch with ventricular septal defect and subaortic stenosis (7); ventricular septal defect, subaortic stenosis, and coarctation of the aorta (7); aortic atresia with large ventricular septal defect (6); tricuspid atresia with transposition of the great arteries (6); heterotaxy syndrome with subaortic obstruction (3); and other (3). There were 10 hospital deaths and 50 survivors (83% survival). After the introduction of inspired carbon dioxide therapy into the postoperative management protocol (1991), 42 of 47 patients survived (89% survival). Mortality was independent of diagnosis and essentially the same as that for hypoplastic left heart syndrome. With minor technical modifications, Norwood's operation provides satisfactory initial palliation for a wide variety of malformations characterized by ductal dependency of the systemic circulation in anticipation of either a Fontan procedure or a biventricular repair. (J THORAC CARDIOVASC SURG 1995;110:1555-62)

Background— The balance of systemic, pulmonary, and coronary blood flow after the Norwood operation for hypoplastic left heart syndrome (HLHS) is critical to early survival. We hypothesized that a right ventricle to pulmonary artery conduit (instead of a systemic to pulmonary artery shunt) would result in hemodynamic changes consistent with a more stable balance of systemic, pulmonary, and coronary perfusion. Methods and Results— Hemodynamic data were obtained during cardiac catheterization before the hemi-Fontan procedure from 24 patients with HLHS; the first 10 had a Norwood operation with a systemic to pulmonary artery shunt, and the latter 14 had the Norwood operation with a right ventricle to pulmonary artery conduit. Significant differences were present, with the right ventricle to pulmonary artery conduit group having a higher aortic diastolic pressure (55 versus 42 mm Hg), a narrowed systemic pulse pressure (43 versus 64 mm Hg), a lower Qp:Qs (0.92 versus 1.42), a higher coronary perfusion pressure (46 versus 32 mm Hg), and a higher ratio of pulmonary artery diameter to descending aorta diameter (1.51 versus 1.37). Conclusions— We conclude that, in HLHS after the Norwood operation, the right ventricle to pulmonary artery conduit modification produces hemodynamic changes consistent with improved coronary perfusion and a more favorable distribution of systemic, pulmonary, and coronary blood flow.

Described here is the use of bilateral pulmonary artery banding as a means to achieve effective restoration of adequate systemic blood flow before a Norwood procedure in two newborns with hypoplastic left heart syndrome who presented after birth with a severe imbalance of Qp/Qs and multiorgan system dysfunction despite usual pharmacologic and ventilatory strategies.

Objective. The purpose of this investigation was to determine the pharmacokinetic disposition of intravenous allopurinol and its metabolite oxypurinol in neonates with the hypoplastic left heart syndrome (HLHS) and to evaluate the subsequent degree of xanthine oxidase inhibition using serum uric acid as a marker. Methods. Pharmacokinetic data were evaluated in 12 stable preoperative neonates with HLHS after a single intravenous allopurinol administration of 5 mg/kg or 10 mg/kg. Pharmacokinetic parameters were determined for elimination half-life, clearance, volume of distribution, and mean residence time. Xanthine oxidase inhibition, measured by serum uric acid reduction, was also measured. Results. Pharmacokinetic parameters revealed no statistically significant differences between a 5-mg/kg and 10-mg/kg dose of intravenous allopurinol on elimination half-life, clearance, volume of distribution, and mean residence time. Mean serum uric acid levels were significantly reduced from baseline by 39.99 and 42.94%, respectively, in the 5- and 10-mg/kg treatment groups. Discussion. The enzyme xanthine oxidase plays a key biochemical role in the generation of toxic oxygen-derived free radicals during ischemia-reperfusion conditions. Allopurinol and its active metabolite oxypurinol inhibit xanthine oxidase, and significantly reduce the conversion of hypoxanthine to xanthine and xanthine to uric acid. Cell injury may be caused by toxic oxygen free radicals produced by ischemia-reperfusion injury such as could occur during the repair of HLHS under hypothermic total circulatory arrest. We hypothesize that allopurinol may provide protection from cellular injury in this clinical context.

The mortality rate of the Fontan operation for heart malformations with a single or dominant ventricle has been reduced by dividing the procedure into two stages. The hemi-Fontan procedure allows early reduction of the volume work of the single ventricle and remodeling of ventricular geometry before a completion Fontan operation. Despite the improvement of survival with this strategy (8% mortality for completion Fontan versus 16% mortality for primary Fontan operation), morbidity related to serous effusions remains substantial. Further technical modifications have been undertaken in an effort to reduce morbidity and further reduce mortality. From January 1990 through June 1993, 200 patients underwent completion Fontan procedures after previous hemi-Fontan operations. Mean age was 23 months, and 157 patients were less than 24 months of age. Diagnoses were hypoplastic left heart syndrome (127 patients), tricuspid atresia (19 patients), single left ventricle (17 patients), complex double-outlet right ventricle (16 patients), pulmonary atresia with intact ventricular septum (8 patients), and other (13 patients). Overall, early mortality rate was 8% (16 patients). In the last 112 patients, the procedure was modified technically by creating one or more fenestrations in the baffle used to separate systemic venous blood from pulmonary venous blood (36 patients), or by excluding one or more hepatic veins from the systemic venous pathway (76 patients). Early mortality for these 112 patients was reduced to 4.5% (5 patients). Substantial morbidity from serous effusions occurred at a rate of 45% (35 of 78 patients) among survivors who had received neither technical modification.(ABSTRACT TRUNCATED AT 250 WORDS)

To document and quantitate changes in right ventricular (RV) geometry and heart rate, we prospectively examined 35 consecutive patients with hypoplastic left heart syndrome under steady-state conditions (chloral hydrate sedation) before and after a bidirectional cavopulmonary anastomosis (hemi-Fontan) procedure. Right ventricular end-diastolic volume (RVEDV) was calculated as the product of RV cavity areas in two orthogonal planes divided by RV maximal length in either plane. After the hemi-Fontan procedure, RVEDV decreased by 33% from 33 +/- 13 to 22 +/- 11 mL (mean +/- standard deviation). Indexed RVEDV decreased from 86 +/- 37 to 57 +/- 28 mL/m2. The RV wall thickness at the diaphragm in subcostal frontal view (RVWD) increased by only 11% from 8 +/- 0.2 to 9 +/- 0.2 mm (p = not significant), but RVWD/RVEDV increased by 111% from 0.36 +/- 0.22 to 0.76 +/- 0.69 mm/mL (p = 0.002). The RV anterior wall thickness in subcostal sagittal view (RVWA) increased by only 13% from 7 +/- 0.2 to 8 +/- 0.2 mm (p = not significant), but RVWA/RVEDV increased by 103% from 0.31 +/- 0.20 to 0.63 +/- 0.54 mm/mL (p = 0.002). In 11 of 35 patients (31%), resting heart rate did not change (118 +/- 14 versus 108 +/- 9 beats/min; p = not significant); however, in 24 of 35 patients (69%), heart rate increased significantly (108 +/- 9 versus 127 +/- 10 beats/min; p = 0.05). In conclusion, RV wall thickness is high before the hemi-Fontan procedure and increases slightly in the first postoperative week.(ABSTRACT TRUNCATED AT 250 WORDS)

Since 1985, 354 neonates have undergone palliative reconstruction for hypoplastic left heart syndrome with 109 early deaths and 12 late deaths. Of the survivors, before 1989, 77 patients underwent a subsequent modified Fontan operation, consisting of baffling the atrial septal defect to the tricuspid valve (initial 25 patients) or intraatrial baffling of the inferior vena cava to the pulmonary arteries and superior vena cava (52 patients). There were 17 early deaths and three late deaths. Major serous effusions developed in 42 patients (54%) after Fontan operation. Since 1989, a staged approach to Fontan's operation was undertaken in an effort to reduce the volume load of the right ventricle as early as possible, to minimize the impact of rapid changes in ventricular geometry and diastolic function that can accompany a primary Fontan operation, and to reduce effusive complications. Thus, at a mean age of 6 months, 121 patients have undergone closure of aortopulmonary shunt, augmentation of central pulmonary arteries, and association of the superior vena cava with the branch pulmonary arteries (hemi-Fontan procedure). Of these, 61 patients have already undergone completion of the Fontan procedure with six early deaths and three late deaths. Major serous effusions developed in 28 patients (46%) with the staged Fontan. For perspective, the contemporary experience since January 1991 consists of 58 neonates who have undergone initial palliation with 11 deaths (19%), 17 patients who have undergone the hemi-Fontan procedure with one death (6%), and 21 patients who have undergone completion of the Fontan operation with one death (5%).(ABSTRACT TRUNCATED AT 250 WORDS)

Differentiation between anomalous connection and anomalous drainage of the pulmonary veins in hypoplastic left heart syndrome is important before either the Norwood procedure or heart transplantation is performed. To determine the prevalence of echocardiographically detected anomalous connection or drainage, or both, of pulmonary veins in patients with this syndrome, preoperative two-dimensional echocardiographic and Doppler color flow mapping studies of 317 patients who underwent the stage I Norwood procedure were reviewed. The term “connection” was used to describe the precise anatomic attachment of the pulmonary veins and the term “drainage” to describe the physiologic end point of pulmonary venous flow.Twenty patients (6.3%) had anomalous connection or drainage, or both, of the pulmonary veins by preoperative echocardiographic and Doppler examination. The subcostal and suprasternal scans best showed the anatomic details of the pulmonary veins. All these patterns were confirmed intraoperatively and could be grouped as follows: 1) partial anomalous connection and drainage (two patients); 2) total anomalous connection and drainage (eight patients); 3) normal connection with total anomalous drainage (eight patients); and 4) normal connection with partial anomalous drainage (two patients). The advantage of adding Doppler color flow mapping to two-dimensional echocardiography and conventional Doppler study was clearly demonstrated in the detection of small accessory vertical veins, their course and the presence or absence of obstruction. Doppler color flow mapping was especially helpful in detecting anomalous drainage of the right pulmonary veins to the right of the superior attachment of the septum primum.

Objective To determine pulmonary mechanical characteristics in neonates after cardiac surgery. Design A prospective study. Setting A 23-bed, pediatric ICU in a 280-bed children's hospital. Patients Twenty-six infants on the first post-operative day after cardiac surgery. Methods Pulmonary mechanics measurements were made during spontaneous breathing, using the esophageal balloon technique and a pneumotachometer. The least mean square method of analysis was used to calculate mechanics. Infants who tolerated withdrawal of mechanical ventilation (group 1) were compared with those infants with respiratory failure (group 2). Results Spontaneous respiratory rate, tidal volume, and minute ventilation were similar in groups 1 and 2. Lung compliance was decreased, with no difference between groups. Total lung resistance (34.3 +/- 21.6 cm H2O/L.sec in group 1 vs. 136.8 +/- 105.8 cm H2O/L.sec in group 2, p = .002) and resistive work of breathing (33.4 +/- 29.9 g.cm/kg in group 1 vs. 212.9 +/- 173.8 g.cm/kg in group 2, p = .001) were significantly higher in group 2. All infants with a total lung resistance greater than 75 cm H2O/L.sec exhibited respiratory failure (resistance greater than 75 cm H2O/L.sec correlated with respiratory failure, r2 = .73, odds ratio of 70 [confidence interval, 4.4 to 3240], p less than .001). Conclusions Increased lung resistance identifies neonates with respiratory failure after cardiac surgery. Pulmonary mechanics testing may be useful in timing withdrawal of mechanical ventilation.

BACKGROUND We reviewed the outcome of 76 consecutive patients (age range, 5 months to 6 years; median age, 19 months) who underwent a modified Fontan procedure after initial palliative surgery for hypoplastic left heart syndrome (HLHS) between January 1984 and December 1989. METHODS AND RESULTS Modifications of the Fontan procedure included transatrial baffle of pulmonary venous return to the tricuspid valve (n = 10) or inferior vena cava baffle within the right atrium to the superior vena caval-pulmonary artery anastomosis, with pulmonary artery augmentation (n = 66). Actuarial survival rates were 74% (1 month), 58% (12 months), 56% (2 years), and 52% (4 years). Of the 43 survivors, 25 patients have returned for postoperative cardiac catheterization at a medium of 13 months after the Fontan procedure. Mean +/- SD hemodynamic values were cardiac index, 2.8 +/- 0.6 l/min/m2; right arterial pressure, 11 +/- 2 mm Hg; pulmonary artery wedge pressure, 6 +/- 3 mm Hg; and arterial oxygen saturation, 94 +/- 3%. No patient had significant tricuspid or native pulmonary valve insufficiency. CONCLUSIONS Survival after the Fontan procedure in patients with HLHS is comparable to survival after a Fontan procedure in patients with other complex congenital heart lesions. In the subgroup of patients with HLHS who survived both reconstructive surgery and a Fontan procedure and have been evaluated by cardiac catheterization after a Fontan procedure, the use of the right ventricle as the systemic ventricle yielded excellent intermediate results for Fontan physiology.

Between March 1986 and April 1990, 22 consecutive fetuses (at gestational ages of 21 to 38 weeks) with a suspected diagnosis of critical (ductus-dependent) left ventricular outflow tract obstruction on fetal echocardiogram were referred to our center for delivery and surgical treatment. Diagnoses were hypoplastic left heart syndrome (n = 16), valvular aortic stenosis (n = 2), common atrioventricular canal with subaortic stenosis (n = 3), and single ventricle with subaortic stenosis (n = 1). Postnatal echocardiography revealed that fetal echocardiography was correct in predicting left ventricular outflow tract obstruction to be critical in all but one patient, for a positive predictive value of 96%. Of the 21 patients with true, critical left ventricular outflow tract obstruction, 17 patients underwent cardiac surgery as neonates (birth to 6 days of age, median 2 days); 13 (or 77%) survived and were discharged from the hospital. In addition, one patient underwent successful balloon aortic valvotomy for critical valvular aortic stenosis but later died of sepsis. Lethal chromosomal and congenital abnormalities should be sought and are contraindications for this approach. In utero transport of fetuses with suspected critical left ventricular outflow tract obstruction to a neonatal cardiac surgical center can result in improved neonatal condition and may improve overall survival.

The Fontan procedure results in right atrial distention and is complicated by fluid retention. Since systemic fluid balance may be hormonally mediated in part and related to right atrium size, we measured plasma atrial natriuretic factor and plasma arginine vasopressin levels in 19 patients undergoing the Fontan procedure and in 12 control patients undergoing other types of heart operations. Preoperative plasma atrial natriuretic factor levels were higher in patients undergoing the Fontan procedure than in control patients (95 ± 16 pg/ml preoperatively versus 50 ± 8 pg/ml; p

Between December 1985 and April 1990, 50 infants with a variety of congenital cardiac lesions other than the hypoplastic left heart syndrome underwent surgical relief of aortic outflow obstruction by creation of a pulmonary artery to aorta anastomosis. The patients were grouped anatomically by ventriculoarterial alignment. Nineteen had normally aligned great arteries (group I); 25 had transposition of the great arteries, all with a univentricular heart of left ventricular morphology (group II); and 6 had a double-outlet right ventricle (group III). All patients had either aortic stenosis with atresia, subaortic stenosis or a restrictive ventricular septal defect. Sixteen had normal arch anatomy; 34 had arch anomalies consisting of arch hypoplasia (n = 17), coarctation (n = 11), interruption of the arch (n = 4) and complex arch anomalies (n = 2). Surgery was performed at a median age of 10 days (range 2 to 184). Of the 50 infants, 33 survived. No significant difference in early survival (30 days) was noted among the groups of varying ventriculoarterial alignment (68% group I, 72% group II, 83% group III) (p greater than 0.05). Overall actuarial survival was 63% at 18 months. Analysis of actuarial survival by arch anatomy, although not statistically significant, revealed a trend toward better survival at 18 months postoperatively in infants with normal arch anatomy (81%) than in infants with arch anomalies (54%). Of the 33 survivors, 26 have proceeded to the next surgical stage, including the Fontan procedure in 8, superior cavopulmonary anastomosis in 13 and biventricular repair in 5.(ABSTRACT TRUNCATED AT 250 WORDS)

In a double-blind study, we compared the postoperative (post-op) blood loss in 161 children undergoing open heart surgery with cardiopulmonary bypass whose immediate post-op transfusion requirements were met with either very fresh whole blood (VFWB), 24- to 48-hour-old whole blood or reconstituted whole blood (packed red blood cells, fresh frozen plasma [FFP], and platelets). Assignment to treatment groups was not strictly random but dependent, in part, on the ability of families to provide directed donors for fresh blood. The three patient groups were comparable with respect to patient age, pre-op coagulation profiles (bleeding time, prothrombin time, activated partial thromboplastin time, platelet count, fibrin split products, fibrinogen, and platelet aggregation tests) difficulty of operative procedures and time spent on CPB. Mean 24-hour post-op blood loss in milliliters per kilogram was 50.9 +/- 9.3 in the VFWB group, 44.8 +/- 6.0 in the 24- to 48-hour-old group, and 74.2 +/- 8.9 in the reconstituted group (p = .03). When blood loss was compared in the 93 children less than 2 years of age, mean blood loss was 52.3 +/- 10.8 in the VFWB group, 51.7 +/- 7.4 in the 24- to 48-hour-old group, and 96.2 +/- 10.7 in the reconstituted group (P = .001). For subjects who had received reconstituted blood, 30- minute and 3-hour post-op platelet aggregation responses to adenosine diphosphate (10 mumol/L) and 30-minute aggregation response to epinephrine (2.5 mumol/L) were more depressed than in the VFWB and 24- to 48-hour groups (P less than .001, P = .005, and P = .02). Comparison of other post-op coagulation tests could not explain the increased blood loss in the reconstituted group. We conclude that the transfusion of less than 48 hours old whole blood is associated with significantly less post-op blood loss than the transfusion of packed red blood cells, FFP, and platelets in children under 2 years old who underwent complex cardiac surgery. The blood losses associated with the transfusion of VFWB and 24- to 48-hour-old blood are comparable and may be, in part, due to better functioning platelets.

The protective effects of hypothermia and potassium-solution cardioplegia on high-energy phosphate levels and intracellular pH were evaluated in the newborn piglet heart by means of in vivo phosphorus nuclear magnetic resonance spectroscopy. All animals underwent cardiopulmonary bypass, cooling to 20° C, 120 minutes of circulatory arrest, rewarming with cardiopulmonary bypass, and 1 hour off extracorporeal support with continuous hemodynamic and nuclear magnetic resonance spectroscopic evaluation. Group I (n = 5) was cooled to 20° C; group II (n = 4) was given a single dose of 20° C cardioplegic solution; group III (n = 7) was given a single dose of 4° C cardioplegic solution; and group IV (n = 4) received 4° C cardioplegic solution every 30 minutes. At end ischemia, adenosine triphosphate, expressed as a percent of control value, was lowest in group I 54% ±6.5% but only slightly greater in group II 66% ± 7.0%. Use of 4° C cardioplegic solution in groups III and IV resulted in a significant decrease in myocardial temperature, 9.9° C versus 17° to 20° C, and significantly higher levels of adenosine triphosphate at end ischemia; with group III levels at 72% ± 6.0% and group IV levels at 73% ±6.0%. Recovery of adenosine triphosphate with reperfusion was not related to the level of adenosine triphosphate at end ischemia and was best in groups I and II, with a recovery level of 95% ±4.0%. In group IV, no recovery of adenosine triphosphate occurred with reperfusion, resulting in a significantly lower level of adenosine triphosphate, 74% ±6.0%, than in groups I and II. Recovery of ventricular function was good for all groups but was best in hearts receiving a single dose of 4° C cardioplegic solution. In this model, multiple doses of cardioplegic solution were not associated with either improved adenosine triphosphate retention during arrest or improved ventricular function after reperfusion, and in fact resulted in a significantly lower level of adenosine triphosphate with reperfusion. The complete recovery of adenosine triphosphate in groups I and II, despite a nearly 50% adenosine triphosphate loss during ischemia, may result from a decrease in the catabolism of the metabolites of adenosine triphosphate consumption in the newborn heart.

A new technique to repair tetralogy of Fallot with an anomalous coronary artery crossing the right ventricular outflow tract is described, together with intermediate term follow-up. Using a pedicled flap of the anterior pulmonary artery wall as the floor, and a vascular or prosthetic patch as the roof, a composite conduit with the potential for growth is constructed. Together with the native outflow tract, this provides unobstructed egress from the right ventricle to the branch pulmonary arteries. Since 1990, 4 infants aged 2-weeks to 6-months have undergone primary repair using this technique. Intermediate term follow-up shows adequate durability of the repair.

An uncommon but historically important form of transposition of the great arteries {S,D,D} was originally recognized in 1971. The unusual features of an aorta that is posterior and to the right of the pulmonary artery, a hypoplastic subaortic conus, and a well-developed subpulmonary conus influenced the evolution of the contemporary classification of conotruncal abnormalities and concepts of their development Presented in this report is the case of a patient with transposition of the great arteries {S,D,D} and posterior aorta treated by an arterial switch operation. The unusual orientation of the great arteries did not preclude coronary transplantation or a satisfactory pulmonary arterial anastomosis. Moreover, the ventricular septal defect, which is characteristic of this atypical form of transposition of the great arteries, was most accessible for closure through the native aortic valve.

The use of Doppler color flow imaging and axial contrast angiography in the preoperative detection of additional ventricular septal defects (in the setting of a known large defect) were compared in a prospective fashion. One hundred seventy-nine infants with two ventricles (each of at least normal size) and a large, nonrestrictive ventricular septal defect underwent reparative surgery before 2 years of age. The reference standard for the presence of additional defects was intraoperadve verification or (in cases in which the surgeon did not visualize any additional defect) subsequent identification at postoperative angiography, postoperative color Doppler examination or reoperation. Only six patients (3%) had additional ventricular septal defects confirmed at the time of repair; an additional five (3%) had defects found only postoperatively. The negative predictive value of Doppler color flow imaging and angiography was 0.95 (168 of 176) and 0.97 (168 of 174), respectively. The sensitivity was 0.27 (3 of 11) and 0.45 (5 of 11), respectively. For certain malformations with a very low prevalence of additional muscular defects (such as perimembranous ventricular septal defect with normally aligned great arteries), a clinical trial of reparative surgery without prior invasive study appears reasonable.

A 4-year-old child with hypoplastic left heart syndrome and a 6-year-old child with tricuspid atresia had both undergone staged reconstructive operations culminating in a Fontan operation. Peripheral edema, ascites, and hypoalbuminemia refractory to dietary manipulation and steroid therapy developed in both patients. After hemodynamic assessment, each child underwent surgical creation of a 4.8-mm fenestration in the previously placed baffle that separated the systemic venous pathway from the pulmonary venous atrium. Peripheral edema and ascites promptly resolved and serum protein levels normalized within 2 weeks after operation. Systemic arterial saturation is 86% in each child, and both children remain clinically well with no evidence of protein-losing enteropathy on normal diets and without specific medical therapy.

The status of pulmonary circulation is of utmost importance to the success of the modified Fontan operation. Pulmonary artery distortion, hypoplasia of the total pulmonary vascular bed, and elevated pulmonary vascular resistance are all risk factors for adverse outcome after modified Fontan operations. In cases of irreparable acquired atresia of one or the other branch pulmonary artery, clinicians are forced to contemplate the possibility of total cavopulmonary connection to one lung. The combined experience of the authors with 12 cases suggests that the likelihood of operative survival following Fontan's operation to one lung is predicted based on the usual hemodynamic parameters: pulmonary artery pressure and flow, ventricular end diastolic pressure, transpulmonary gradient, and pulmonary vascular resistance. In this series, there were no operative mortalities among patients undergoing Fontan's operation to one lung, all of whom meet the usual criteria for hemodynamic acceptability. There may, however, be a higher incidence of protein-losing enteropathy than in Fontan patients with normal pulmonary vascular beds. All possible means of resuscitating the lost elements of the pulmonary vascular bed and re-establishing pulmonary artery continuity should be attempted to minimize pulmonary vascular capacitance of patients undergoing Fontan's operation. It is clear, however, that the presence of only one pulmonary artery does not in and of itself preclude satisfactory outcome.

Background Subaortic obstruction is a frequent accompaniment of single-ventricle anatomy. Most often, the aorta arises from an outflow chamber that is connected to the single ventricle by a bulboventricular foramen or ventricular septal defect. This connection may be restrictive of flow at birth, or may become obstructive after surgical procedures that reduce the volume work of the ventricle. Subaortic obstruction is recognized as a risk factor for reconstructive surgical procedures for single ventricle. Methods To prevent the consequences of subaortic obstruction, we have routinely amalgamated the proximal main pulmonary artery with the ascending aorta and arch early in the management of these patients. From September 1990 through September 1994, 29 neonates and infants with single ventricle and established or potential subaortic obstruction underwent staged reconstructive surgical procedures. The initial operation in the newborn period was a Norwood procedure (18 patients) or a pulmonary artery band (5 patients). All survivors underwent a hemi-Fontan procedure at approximately 6 months. Results Eighteen patients have undergone a completion Fontan operation with no deaths. Five await completion Fontan. None has subaortic obstruction, and none has pulmonary valve insufficiency that is graded more than mild. Conclusions Early association of the proximal main pulmonary artery with the ascending aorta appears to obviate the risks and complications associated with subaortic obstruction in patients with single ventricle.

Background— Diastolic run off into the pulmonary circulation and labile coronary perfusion are thought to contribute to morbidity and mortality after the Norwood procedure (NP). We compared outcomes from the use of a RV to PA conduit (RV/PA) or a modified Blalock-Taussig shunt (BTS), physiologically distinct sources of pulmonary blood flow. Methods and Results— Review of 56 consecutive patients who underwent a Norwood procedure with a RV/PA (n=36) or a BTS (n=20) between 2000 and 2002. Median age was 4.5 days (range 1 to 40) and median weight was 3.1 kg (range 1.8 to 4.1). The RV/PA was constructed with a 5-mm conduit. Patients in the BTS group received a 4-mm shunt. Comparisons between RV/PA and BTS groups showed no difference for weight, gestational age, prenatal diagnosis, HLHS variant, associated diagnoses, ascending aortic size, ventricular function, AV valve function, and pulmonary venous obstruction. Operative survival was higher with RV/PA [33/36 (92%) versus 14/20 (70%); P =0.05]. Patients with RV/PA had less need for ventilatory manipulations to balance the Qp/Qs (1/36 v/s 8/20; P =0.001), delayed sternal closure (6/36 v/s 7/20; P =0.001), and extracorporeal support (5/36 v/s 7/20; P =0.036). RV/PA patients had more favorable postoperative hemodynamics: higher diastolic blood pressure without changes in systolic blood pressure at 1, 8, 24, 48 hours after the NP (46.3 v/s 39.5; 47.2 v/s 42.1; 46.1 v/s 37.1; and 47.1 v/s 40.2; all P =0.001). Conclusion— RV/PA simplifies postoperative management and improves hospital survival after NP for HLHS.

Objective.This pharmacologic protection trial was conducted to test the hypothesis that allopurinol, a scavenger and inhibitor of oxygen free radical production, could reduce death, seizures, coma, and cardiac events in infants who underwent heart surgery using deep hypothermic circulatory arrest (DHCA).Design.This was a single center, randomized, placebo-controlled, blinded trial of allopurinol in infant heart surgery using DHCA. Enrolled infants were stratified as having hypoplastic left heart syndrome (HLHS) and all other forms of congenital heart disease (non-HLHS). Drug was administered before, during, and after surgery. Adverse events and the clinical efficacy endpoints death, seizures, coma, and cardiac events were monitored until infants were discharged from the intensive care unit or 6 weeks, whichever came first.Results.Between July 1992 and September 1997, 350 infants were enrolled and 348 subsequently randomized. A total of 318 infants (131 HLHS and 187 non-HLHS) underwent heart surgery using DHCA. There was a nonsignificant treatment effect for the primary efficacy endpoint analysis (death, seizures, and coma), which was consistent over the 2 strata. The addition of cardiac events to the primary endpoint resulted in a lack of consistency of treatment effect over strata, with the allopurinol treatment group experiencing fewer events (38% vs 60%) in the entire HLHS stratum, compared with the non-HLHS stratum (30% vs 27%). In HLHS surgical survivors, 40 of 47 (85%) allopurinol-treated infants did not experience any endpoint event, compared with 27 of 49 (55%) controls. There were fewer seizures-only and cardiac-only events in the allopurinol versus placebo groups. Allopurinol did not reduce efficacy endpoint events in non-HLHS infants. Treated and control infants did not differ in adverse events.Conclusions.Allopurinol provided significant neurocardiac protection in higher-risk HLHS infants who underwent cardiac surgery using DHCA. No benefits were demonstrated in lower risk, non-HLHS infants, and no significant adverse events were associated with allopurinol treatment.congenital heart defects, hypoplastic left heart syndrome, induced hypothermia, ischemia-reperfusion injury, neuroprotective agents, allopurinol, xanthine oxidase, free radicals, seizures, coma.

Partial left ventriculectomy for dilated cardiomyopathy was first reported by Batista and associates1 in 1996. The rationale for this procedure is the increase in left ventricular cavity size in the absence of compensatory left ventricular wall thickness that is observed in dilated cardiomyopathy. This combination of factors results in an increase in wall stress per unit muscle mass, as predicted by the LaPlace equation. As wall stress increases, mechanical load eventually becomes nonsustainable and contributes to further dilation of the ventricle. Partial left ventriculectomy has been advocated as a method of restoring the balance between cavity size and wall thickness. Fundamental to this concept is the assumption that the left ventricular muscle is intrinsically normal or has recoverable contractile function. The variable results that have been reported in the adult literature may reflect patient selection according to the reversibility or recoverability of the underlying disease process. Despite the substantial worldwide experience with the Batista procedure in adult patients, there is limited experience with this procedure in children. The current case report describes the treatment of a patient in whom the diagnosis of dilated cardiomyopathy was made in utero. Clinical summary. A female infant was recognized in utero as having a dilated, poorly functioning left ventricle. Labor was induced at 36 weeks’ gestation, and she was delivered by normal, spontaneous, vaginal delivery. She underwent tracheal intubation in the delivery room because of poor tone and cyanosis. After her condition was stabilized, she was transferred to this institution. A postnatal echocardiogram again revealed massive dilation of the left ventricle with severely depressed systolic function. There was mild mitral valve hypoplasia with severe insufficiency. The aortic valve anulus measured 7 mm in diameter, and the valve appeared normal. The aortic arch was unobstructed, but there was retrograde flow via the ductus into the transverse aortic arch. The right ventricular systolic function appeared to be normal. A chest film revealed marked cardiac enlargement with compression of the left lung. From Nemours Cardiac Center, Alfred I. duPont Hospital for Children, Wilmington, Del. Received for publication Jan 18, 2000; accepted for publication Feb 18, 2000. Address for reprints: Richard D. Mainwaring, MD, Nemours Cardiac Center, Alfred I. duPont Hospital for Children, PO Box 269, Wilmington, DE 19899 (E-mail: rmainwar@nemours.org). J Thorac Cardiovasc Surg 2000;120:612-5 Copyright © 2000 by The American Association for Thoracic Surgery 0022-5223/2000 $12.00 + 0 12/54/106657 doi:10.1067/mtc.2000.106657 NORWOOD/BATISTA OPERATION FOR A NEWBORN WITH DILATED MYOPATHY OF THE LEFT VENTRICLE

Partial hepatic vein exclusion, as an alternative to baffle fenestration, has been performed as a modification of the Fontan procedure. We report a case of severe cyanosis resulting from massive right-to-left shunting via a hepatic vascular malformation that developed in a patient after a modified Fontan procedure with partial hepatic vein exclusion.

Abstract Interrupted aortic arch (IAA) is often related developmentally to subaortic obstruction (SAO). When severe, SAO must be addressed in surgical management of IAA. From 1990 to 1993, 25 neonates presented for initial surgical management of IAA complexes. Associated lesions were ventricular septal defect (VSD) with or without atrial septal defect (19 patients), truncus arteriosus (3 patients), tricuspid atresia with transposition of the great arteries (1 patient), aortic atresia with VSD (1 patient), and d-transposition of the great arteries with VSD (1 patient). Overall hospital mortality was 20% (five deaths). One death was related to sepsis and two to sudden hemodynamic decompensation (a 2-kg premature infant after arch repair and VSD closure and a neonate with IAA–truncus arteriosus after arch repair and truncus repair with aortic root replacement). Two deaths were related to low cardiac output in patients with severe subaortic narrowing (

Objectives.This study investigated the phenomenon of, and the relation between, alterations in ventricular geometry after acute surgical volume unloading of the ventricle and the development of subaortic stenosis in patients with a single ventricle and ventricular septal defect—dependent systemic flow.Background.Subaortic outflow obstruction has been observed to occur in patients with a single left ventricle after placement of a pulmonary artery band. The timing and etiology of this phenomenon are not well defined.Methods.The preoperative and postoperative echocardiograms of 18 patients 14.9 ± 22.8 months old (mean ± SD) with a diagnosis of single left ventricle who underwent pulmonary artery banding or cavopulmonary connection were reviewed. Postoperative studies were performed a mean of 7.0 ± 6.5 days after operation. The ventricular septal defect diameter was measured in two orthogonal views and the area calculated using the formula for an ellipse. Interventricular septal and posterior wall thickness and left ventricular diameter and length were also measured.Results.Mean ventricular septal defect area indexed to body surface area diminished by 36 ± 23% (3.1 ± 2.7 to 2.0 ± 1.8 cm2/m2, p < 0.01). Mean interventricular septal and posterior wall thickness increased significantly, and left ventricular diameter and length decreased significantly. A greater diminution in ventricular septal defect area was noted after cavopulmonary connection (41 ± 19%, p < 0.01) than after pulmonary artery banding (25 ± 28%, p = 0.22).Conclusions.In the single left ventricle, diminution in ventricular septal defect size occurs early and is related to an acute alteration in ventricular geometry that accompanies the decrease in ventricular volume. Ventricular septal defect diminution was greater after volume unloading of the ventricle after cavopulmonary connection than after pulmonary artery banding.

Acute removal of a ventricular volume overload, in the face of relatively unchanging ventricular mass, results in geometric alterations that can impair diastolic ventricular performance after Fontan operation. We investigated whether geometric alterations were (1) more severe after Fontan operation than after hemi-Fontan operation, (2) more severe in infants than in children, and (3) more severe in the morphologic right ventricle than in the morphologic left ventricle. We studied 22 patients, 11 with hypoplastic left heart syndrome and 11 with a functionally single morphologic left ventricle. After Fontan operation, right ventricular end-diastolic volume declined by 52% from 36.6 +/- 12.2 to 17.5 +/- 9.3 mL. Right ventricular wall thickness increased from 6.8 +/- 1.3 to 7.5 +/- 1.8 mm. Left ventricular end-diastolic volume diminished by 40% from 57.6 +/- 23.3 to 34.8 +/- 17.6 mL. Left ventricular wall thickness increased from 7.0 +/- 2.1 to 8.7 +/- 1.9 mm. The alterations in right ventricular geometry are more marked early after Fontan operation than early after the hemi-Fontan procedure. Geometric alterations in the left ventricle appear to be more severe in infants than in children. Finally, alterations in the morphologic right ventricle appear to be of similar magnitude to those in the morphologic left ventricle.

Hypoplastic left heart syndrome (HLHS) has been widely viewed as a uniformly fatal form of congenital heart disease. Between January 1984 and December 1990, 387 patients with the diagnosis of HLHS were treated at this institution. Mesenteric ischemia was clinically diagnosed in 31 patients (8% incidence) and confirmed by pathology or surgery in 25 of those patients. The mean age at the time of onset was 17.5 +/- 5.4 weeks and only 13% were premature newborns. In 80% of the patients a low perfusion state and significant hypotension were documented within 48 hours prior to the diagnosis of bowel ischemia. Nine patients (29%) required operative intervention (bowel resection 4, diffuse ischemia 3, and simple drainage 2). Overall, at operation or at autopsy, nine patients (29%) had diffuse gastrointestinal ischemia. Of 31 patients with mesenteric ischemia, 26 children (84%) died shortly after onset of the gastrointestinal symptoms regardless of means of management. Five patients (10%) initially improved with aggressive medical and/or surgical management; however, 4 subsequently died secondary to complications of their primary cardiac disease. Therefore, the overall mortality of patients with mesenteric ischemia was 97%. Previous reports have estimated that up to 7% of full-term newborns with symptomatic congenital heart disease may develop necrotizing enterocolitis (NEC). Our unique group of patients with HLHS is comprised mostly of full-term infants who developed onset of mesenteric ischemia at a mean age of 4 months associated with an underlying low perfusion state. This mesenteric ischemia has been erroneously identified as NEC.(ABSTRACT TRUNCATED AT 250 WORDS)

A neonate with tetralogy of Fallot and aortic coarctation is described. The clinical course was remarkable, with early congestive heart failure followed by rapidly progressive left ventricular myocardial thickening and the presentation of hypercyanotic spells. Primary repair of tetralogy without correction of coarctation was attempted unsuccessfully at 1 month of age. Death followed postoperative bradycardia, hypotension, and low cardiac output. Fetal and neonatal hemodynamics and the clinical implication of this rare combination of defects are discussed. Initial surgical intervention should relieve left-sided obstruction.

The evolution of the present approach to the newborn with hypoplastic left heart is outlined. Preoperatively, maintenance of ductal patency with prostaglandin E1 and balancing of systemic and pulmonary blood flow are essential. Operative details of the first-stage palliation and the definitive second-stage procedure are described. The more recent adoption of an intermediate-stage hemi-Fontan procedure is also described. Since January 1989, 151 patients have been treated using this three-stage approach, with 109 early survivors. Seventy-eight have undergone the hemi-Fontan operation with nine deaths (5 of whom came to this stage early nonelectively because of shunt failure or ventricular dysfunction). Twenty-seven of the 78 patients undergoing hemi-Fontan operation have subsequently undergone definitive Fontan procedures with no deaths.

The hypoplastic left heart syndrome, which characteristically presents in the first few hours of life with cardiovascular collapse, is treated by reconstructive surgery (Norwood's procedure) beginning in the neonatal period. If untreated, more than 95% of infants with this malformation die within the first month of life. The case described involves the development of increasing cyanosis 7 weeks following bilateral superior vena caval-pulmonary artery (SVC-PA) anastomosis in an infant born with a hypoplastic left heart (including aortic and mitral valve stenosis) and an anatomic variant of bilateral superior vena cavae. The use of Tc-99m MAA proved efficacious in quantitating the differential perfusion to each lung, establishing the site of a postoperative stenosis in an anastomotic channel, and documenting systemic perfusion, thus confirming the right-to-left shunt from the superior vena cava to the systemic circulation that resulted in increasing cyanosis.

Circulatory and metabolic homeostasis in patients with hypoplastic left heart syndrome is dependent on a delicate balance between systemic and pulmonary blood flow. Hypocarbia can result in a marked decrease in pulmonary vascular resistance accompanied by pulmonary overcirculation, systemic hypotension, metabolic acidosis, and death. This report illustrates that early and precise control of the arterial carbon dioxide tension using inspired carbon dioxide can be effective in preventing or treating instability arising during management of a patient with hypoplastic left heart syndrome.

Young children undergoing complex cardiac operation lose more blood after cardiopulmonary bypass than do older patients. This study was designed to investigate the effect of desmopressin on blood loss during the first 24 hours after cardiac operation in children undergoing principally complex surgical procedures. The study consisted of a randomized, blinded comparison of 112 pediatric patients who received either desmopressin 0.3 microgram/kg or saline solution placebo after cardiopulmonary bypass. A coagulation profile including bleeding time, quantitation of von Willebrand factor, and qualitative analysis of the factor VII:von Willebrand factor complex was performed before, 30 minutes after, and 3 hours after the operation. Blood loss and blood replacement were recorded for the first 24 hours after the operation. The surgeon classified the technical difficulty of each procedure as simple or complex. Statistical analysis was performed with Student's unpaired t test and chi 2 analysis. Significance was defined as p < 0.05. Results are listed as mean +/- standard deviation. Data collection was completed for 95 patients. The mean age of all patients was 26 +/- 40 months, and the mean weight was 10 +/- 11 kg, with 84% undergoing complex procedures. There were no differences between the desmopressin and placebo groups with respect to age, weight, or surgical complexity. Twenty-four-hour blood loss and replacement between the desmopressin and placebo groups were not different (blood loss: desmopressin 30 +/- 33 ml/kg, placebo 35 +/- 36; blood replacement: desmopressin 65 +/- 43 ml/kg, placebo 64 +/- 46 ml/kg). Coagulation profiles between the desmopressin and placebo groups were not different at any time. We conclude that desmopressin does not reduce blood loss or blood replacement in young children after cardiopulmonary bypass for either simple or complex cardiac surgical procedures.