Presentation of atrial septal defect in the pediatric population.

Our recent experience indicates that patients with a hemodynamically significant atrial septal defect secundum (ASD2) do not necessarily present with classic physical and electrocardiographic (ECG) findings. The purpose of the study was to review the records of patients either receiving a catheter device or undergoing surgical repair for the closure of ASD2 to determine their initial physical and ECG findings. Therefore, we did a retrospective review of 47 consecutive patients who had echocardiographic evidence of a hemodynamically significant isolated ASD2 and who underwent ASD2 closure. Of these 47 patients, the presenting complaints were murmur (n = 36), chest pain (n = 6), seizure (n = 1), stroke (n = 1), syncope (n = 1), Kawasaki's disease (n = 1), and cardiomegaly (n = 1). Charts were reviewed for the evaluation of four abnormal physical findings: hyperactive right ventricular impulse, split fixed second heart sound, systolic and diastolic flow murmurs; and three ECG abnormalities: right axis deviation, right atrial enlargement, and evidence of right ventricular hypertrophy. In all, 30% of patients had either one or no typical physical findings, 18% had normal ECG findings, and 7% had no physical or ECG findings. On physical examination and ECG, the abnormalities due to ASD2 may be too subtle to detect. Although it is well known that variations can occur in the clinical signs and symptoms typical of ASD2, dependence on classical physical and or ECG findings may result in the underdiagnosis of a significant number of patients.

Morbidities in patients with hypoplastic left heart syndrome.

We sought to document morbidities and growth for patients with hypoplastic left heart syndrome (HLHS) to inform the initial surgical decision and understand healthcare needs. Data were obtained on 137 patients with HLHS, born between 1989 and 1994, who survived staged surgery ( n = 62) or transplantation ( n = 75) and had follow-up information available from four pediatric cardiac surgical centers. In patients with HLHS older than 1 year of age at follow-up, 93% experienced at least one major postsurgical morbidity. Morbidities depended on the surgery received. Hypertension, renal compromise, and abnormal infections were more common in transplanted patients than staged surgery patients. Staged surgery patients used more anticongestive medications and experienced more morbidities requiring interventional catheterization than did transplanted patients. Rejection was common for transplanted patients. On average these children spent 23 days per year in the hospital. Patients with HLHS were small for their age; 43% of staged surgery patients weighed below the third percentile at last information, compared to 19% of transplanted patients ( p = 0.003). The median height percentile was the 10th in both groups. Normal activity level was reported in more transplanted patients (90%) than staged surgery patients (49%; p < 0.001). Trade-offs between mortality and morbidity outcomes can help inform the initial surgical decision.

A comparison of treatment strategies for hypoplastic left heart syndrome using decision analysis.

OBJECTIVES: We sought to identify the optimal treatment strategy for hypoplastic left heart syndrome (HLHS). BACKGROUND: Surgical treatment of HLHS involves either transplantation (Tx) or staged palliation of the native heart. Identifying the best treatment for HLHS requires integrating individual patient risk factors and center-specific data. METHODS: Decision analysis is a modeling technique used to compare six strategies: staged surgery; Tx; stage 1 surgery as an interim to Tx; and listing for transplant for one, two, or three months before performing staged surgery if a donor is unavailable. Probabilities were derived from current literature and a dataset of 231 patients with HLHS born between 1989 and 1994. The goal was to maximize first-year survival. RESULTS: If a donor is available within one month, Tx is the optimal choice, given baseline probabilities; if no donor is found by the end of one month, stage 1 surgery should be performed. When survival and organ donation probabilities were varied, staged surgery was the optimal choice for centers with organ donation rates < 10% in three months and with stage 1 mortality <20%. Waiting one month on the transplant list optimized survival when the three-month organ donation rate was > or =30%. Performing stage 1 surgery before listing, or performing stage 1 surgery after an unsuccessful two- or three-month wait for transplant, were almost never optimal choices. CONCLUSIONS: The best strategy for centers that treat patients with HLHS should be guided by local organ availability, stage 1 surgical mortality and patient risk factors.

Reverse subclavian flap repair of hypoplastic transverse aorta in infancy.

BACKGROUND: Management of hypoplastic aortic arch associated with coarctation in infancy can be challenging. Reverse subclavian flap aortoplasty plus coarctation resection offers simplicity without needing foreign material or cardiopulmonary bypass. METHODS: Since 1988, 46 of 162 infants less than 3 months undergoing coarctation repair had hypoplastic arch enlargement with reverse subclavian flap aortoplasty. Median age was 11 days; mean weight was 3.2 kg. Thirty-seven patients (80%) had associated cardiac defects including single or multiple ventricular septal defects (14 infants), transposition of the great arteries (7), aortic or mitral stenosis (5), and complete atrioventricular septal defect (5 infants). Twenty-eight patients had pulmonary artery banding; 2 had an arterial switch operation through a separate median sternotomy. RESULTS: There were two hospital deaths: one 4 months postoperatively in a patient requiring a Norwood procedure the next day for underestimated left ventricular hypoplasia; the other of sepsis more than 1 month postoperatively. On follow-up from 1 to 129 months (mean, 38 months), there were five recurrent obstructions: three at the coarctation site treated with balloon dilatation and two at the arch site. Twenty-six children had their heart defects corrected with 29 subsequent operations including an arterial switch operation for transposition of the great arteries/ ventricular septal defect (3 infants), relief of aortic or mitral stenosis +/- ventricular septal defect closure (5), multiple ventricular septal defect closure (3), a bidirectional Glenn (2), complete atrioventricular septal defect (2), and anomalous left coronary with ventricular septal defect repair (1 infant). Four children await debanding and ventricular septal defect closure or Glenn anastomosis. There have been two late deaths (overall survival, 91%). CONCLUSIONS: Reverse subclavian flap aortoplasty is excellent for relief of arch hypoplasia and coarctation in infants with low recurrence rates and acceptable operative and intermediate survival.

Saphenous vein homograft: a superior conduit for the systemic arterial shunt in the Norwood operation.

BACKGROUND: Excessive pulmonary blood flow increases ventricular volume work in the face of inadequate systemic cardiac output, low diastolic blood pressure, and inadequate coronary perfusion. Using the smallest available 3-mm polytetrafluoroethylene shunts have been successful, although catastrophic shunt thrombosis has occasionally been observed. To avoid thrombosis with a smaller conduit, saphenous vein homografts (SVG) were used to construct the modified Blalock-Taussig (BT) shunts. METHODS: From January 1998 to April 1999, 25 patients weighing 3.1 kg (3.0 kg or less, n = 9), at a mean age of 8.9 days, underwent stage I Norwood using an SVG BT shunt. Common heart defects were aortic atresia (n = 8), mitral atresia and double-outlet right ventricle (n = 5), and unbalanced AVC (n = 5). Mean BT shunt size was 3.2 mm, with 12 patients having shunts that were 3 mm or smaller. RESULTS: Thirty-day hospital mortality was 8% (2 of 25). No shunt thrombosis was seen, despite banding the BT shunt in 3 patients. One patient had BT revision because of an anatomic issue not directly related to the shunt material. CONCLUSIONS: Excellent results may be achieved using SVG BT shunts in the Norwood operation. This conduit seems less likely to thrombose, both acutely and chronically, allowing the use of appropriately smaller-sized shunts in small neonates.

Outcomes of transcatheter balloon angioplasty of obstruction in the neo-aortic arch after the Norwood operation.

Obstruction of the reconstructed aortic arch, or the neoaortic arch, is now known to be an important factor increasing mortality after the Norwood operation for hypoplastic left heart syndrome. Transcatheter balloon angioplasty has been shown to provide effective relief of both native aortic coarctation and obstructions of the aortic arch occurring subsequent to therapeutic intervention. We sought to determine the outcomes of balloon angioplasty used as an initial treatment for obstruction of the neoaortic arch occurring after the Norwood operation. We gathered the characteristics of 58 patients with such obstruction from 8 institutions, noting procedural factors and outcomes of initial balloon dilation. Obstruction occurred at a median interval of 4 months, with a range from 1.5 months to 6.3 years, after a Norwood operation. Ventricular dysfunction was present before dilation in 13 patients. Mean peak to peak systolic pressure gradients were acutely reduced from 31+/-20 mm Hg to 6+/-9 mmHg (p<0.001), with outcome subjectively judged to be successful in 89%. Three patients with pre-existing ventricular dysfunction died within 48 hours of dilation. There were 10 additional deaths during the period of follow-up, with Kaplan Meier estimates of survival after intervention of 87% at 1 month, 77% at 12 months, and 72% after 15 months. In addition, 9 patients required re-intervention during the period of follow-up, with Kaplan Meier estimates of freedom from re-intervention after dilation of 87% at 6 months, 78% at 12 months and 74% after 18 months. Although transcatheter dilation of neoaortic arch obstructions after Norwood operation is successful, there is a high risk of re-intervention and ongoing mortality in this subgroup of patients. Close follow-up is recommended.

Survival analysis and risk factors for mortality in transplantation and staged surgery for hypoplastic left heart syndrome.

OBJECTIVES: We compared survival in treatment strategies and determined risk factors for one-year mortality for hypoplastic left heart syndrome (HLHS) using intention-to-treat analysis. BACKGROUND: Staged revision of the native heart and transplantation as treatments for HLHS have been compared in treatment-received analyses, which can bias results. METHODS: Data on 231 infants with HLHS, born between 1989 and 1994 and intended for surgery, were collected from four pediatric cardiac surgical centers. Status at last contact for survival analysis and mortality at one year for risk factor analysis were the outcome measures. RESULTS: Survival curves showed improved survival for patients intended for transplantation over patients intended for staged surgery. One-year survival was 61% for transplantation and 42% for staged surgery (p < 0.01); five-year survival was 55% and 38%, respectively (p < 0.01). Survival curves adjusted for preoperative differences were also significantly different (p < 0.001). Waiting-list mortality accounted for 63% of first-year deaths in the transplantation group. Mortality with stage 1 surgery accounted for 86% of that strategy's first-year mortality. Birth weight <3 kg (odds ratio [OR] 2.4), highest creatinine > or =2 mg/dL (OR 4.7), restrictive atrial septal defect (OR 2.7) and, in staged surgery, atresia of one (OR 4.2) or both (OR 11.0) left-sided valves produced a higher risk for one-year mortality. CONCLUSIONS: Transplantation produced significantly higher survival at all ages up to seven years. Patients with atresia of one or both valves do poorly in staged surgery and have significantly higher survival with transplantation. This information may be useful in directing patients to the better strategy for them.

Oral meperidine, atropine, and pentobarbital for pediatric conscious sedation.

PURPOSE: To document the effectiveness and safety of using a combination of oral meperidine, atropine, and pentobarbital for pediatric conscious sedation. METHOD: Sixty-three patients ages 6 months to 23 years (M = 5 years) undergoing outpatient cardiac catheterization were given an oral premedication consisting of meperidine, atropine, and pentobarbital for sedation. The effectiveness of the medication in providing sedation and the complication of over sedation when using a standard dose based upon weight were analyzed. RESULTS: Seventy six percent of the patients were deemed sedated on arrival to the catheterization laboratory. Forty eight percent did not require any further sedation during the procedure. Need for further sedation was related to the length of the procedure. Three patients (4.8%) incurred complications of sedation; all three had received additional sedation during the procedure. CONCLUSIONS: The combination of meperidine, atropine, and pentobarbital is a safe and effective premedication for cardiac catheterization when administered in standard dosage based upon body weight.

Diagnosis and catheter treatment of innominate artery stenosis following stage I Norwood procedure.

Four infants aged 20-115 days (mean, 57.8 days) who had undergone stage I Norwood procedure for hypoplastic left heart syndrome came to early cardiac catheterization (6-112; mean, 47.3 days) following surgery because of significant arterial desaturation (pulse oximetry indicating oxygen saturations consistently in the 40%-70% range). Cardiac catheterization demonstrated a significant systolic pressure gradient between the ascending aorta and innominate artery (30-65; mean, 51 mm Hg) as the likely cause of diminished pulmonary blood flow in these patients. Routine angiography by itself was not conclusive in identifying a discrete area of obstruction, but selective angiography coupled with a knowledge of the obstruction did reveal the stenosis. All patients were successfully treated with balloon dilatation of the stenotic area, with the pressure gradient being reduced to 7-25 (mean, 17 mm Hg) immediately following dilatation. On follow-up catheterization in three patients, the systolic gradients were 3, 6, and 9 mm Hg. Arterial oxygen saturations rose from 63.5% predilatation to 77.3% immediately postdilatation and 81% on follow-up evaluation. In conclusion, innominate artery stenosis is an important cause of diminished blood flow through a modified right Blalock-Taussig shunt. Routine angiography will often miss the diagnosis. Pressure gradients and selective angiograms are necessary in order to make the diagnosis, although careful noninvasive assessment should also be diagnostic of this problem. Catheter dilatation is therapeutic in this situation and can be performed early after surgery in the absence of a fresh suture line.

Importance of acquired systemic-to-pulmonary collaterals in the Fontan operation.

BACKGROUND: Children with chronic cyanotic heart disease often develop systemic-to-pulmonary collateral arteries that can be deleterious at the time of a Fontan procedure due to excessive pulmonary blood flow. We therefore occlude all significant collaterals during cardiac catheterization. METHODS: From June 1993 to May 1998, 93 children aged 1.5 to 15.8 years (median 2.5 years) underwent a fenestrated lateral tunnel Fontan procedure. Eighty-nine (96%) had a previous bidirectional Glenn anastomosis, including 31 (33%) with a Norwood procedure. RESULTS: Preoperatively, 33 children (35%) required occlusion of 1 to 11 (mean 3.6) collateral vessels. Two of the three perioperative deaths (operative survival 97%) were due to excessive pulmonary blood flow from unrecognized collaterals in one and uncontrollable collaterals in the other. Postoperatively, 19 children (20%) required coil occlusion of 1 to 21 (mean 5.6) collaterals for elevated pulmonary artery pressures, heart failure, or prolonged chest tube drainage. Duration of inotropic support, postoperative ventilation, intensive care unit stay, and postoperative hospitalization were all significantly longer in the patients who had postoperative occlusion of collaterals. On follow-up of 2 to 67 months (mean 35 months), there have been four late deaths (two infections, two heart failures); 6 patients underwent successful cardiac transplantation for refractory heart failure. All 8 patients with ventricular failure required occlusion of significant collaterals postoperatively. CONCLUSIONS: Hemodynamically significant collaterals are not uncommon in Fontan candidates, and aggressive control can result in good operative and medium-term survival. After the Fontan, significant collaterals may be a marker for eventual cardiac failure because 8 of 18 patients requiring postoperative coils went on to transplantation or died of heart failure.

Current results with pediatric heart transplantation.

BACKGROUND: Cardiac transplantation is an accepted treatment for children with end-stage heart failure or complex or inoperable congenital defects. METHODS: Since 1988, 95 transplants have been performed in 89 children aged 4 days to 18 years (median 6.9 years, 42 patients 0-5 years). Fifty-eight (61%) had congenital or acquired heart disease, 31 (33%) had idiopathic cardiomyopathy, and 6 (6%) were retransplants. Fifty-seven of the patients had prior cardiac surgery with a range of one to eight procedures (mean 3.4 procedures/patient). At the time of transplantation, 53 (56%) were United Network for Organ Sharing (UNOS) status I, including 23 children on mechanical ventilation and 4 with mechanical circulatory support. RESULTS: Thirty-day survival in this group was 96%. Posttransplant results showed a median time of ventilation of 1 day (mean 3.0+/-5.7 days), median duration of inotropic support of 2 days (mean 2.7+/-2.3 days), median intensive care unit (ICU) stay of 4 days (mean 6.9+/-9.6 days), and median hospitalization of 9 days (mean 14.3+/-13.9 days). Follow-up from 1 month to 10.3 years (mean 3.1 years) has demonstrated a 1-year actuarial survival of 79% and a 5-year actuarial survival of 69%. Rejection, both acute and chronic, accounted for the vast majority of deaths. CONCLUSIONS: Pediatric heart transplantation can be accomplished with excellent early survival despite multiple prior cardiac operations and relative severity of illness. Parameters such as postoperative ventilation, inotropic support, ICU stay, and hospitalization can be kept at reasonable levels with acceptable long-term results, although rejection remains a serious problem.

Transhepatic vascular access in pediatric cardiology patients with occlusion of traditional central venous sites.

Central venous access in pediatric patients with complex congenital heart disease may be difficult. Percutaneous transhepatic access offers an alternative for patients with occlusion of traditional central venous sites. We reviewed our experience utilizing transhepatic access in 10 consecutive pediatric cardiology patients for central venous lines, cardiac catheterization and endomyocardial biopsy. We include 5 patients who have had multiple procedures via the transhepatic approach.

Repetitive percutaneous transhepatic access for myocardial biopsy in pediatric cardiac transplant recipients.

Repetitive transhepatic access for myocardial biopsy in two pediatric cardiac transplant patients is described. Both have documented occlusion of the traditional percutaneous venous sites. Biopsy via the transhepatic route was performed in one patient 11 times and the second patient five times without any complications. The transhepatic approach can be safely used repetitively in pediatric transplant recipients when traditional venous access is not available.

Anomalous origin of the left coronary artery from the pulmonary artery associated with ventricular septal defect and mitral stenosis.

We report a case of a child with ventricular septal defect, mitral stenosis, and patent ductus arteriosus, who was also found to have anomalous origin of the left coronary artery from the pulmonary artery. Preoperative diagnosis allowed successful surgical correction.

Comparison of quantitative echocardiography with endomyocardial biopsy to define myocardial rejection in pediatric patients after cardiac transplantation.

Endomyocardial biopsy is the gold standard for determining rejection; however, no echocardiographic indexes have been widely accepted as indicators of rejection. The stress-velocity relation of corrected velocity of circumferential fiber shortening to wall stress is a preload independent index of contractility that incorporates afterload and has been shown to distinguish a decreased velocity caused by excess afterload from that caused by decreased contractility. Wall stress has not been previously reported as a determinant of rejection. We report a prospective double-blind study of pediatric cardiac transplant patients comparing biopsy and quantitative systolic echocardiographic data. Thirty-two pediatric patients underwent 67 biopsies. At the time of catheterization, an echocardiographic evaluation was performed. Standard measurements of systolic function were collected and left ventricular (LV) fractional shortening, LV volume, LV mass, velocity of circumferential fiber shortening, and estimated end-systolic wall stress were calculated. In evaluating echocardiographic data of patients with and without biopsy-proven rejection, we were unable to identify any significant correlation between any systolic echocardiographic parameter and rejection. We conclude that: (1) the stress-velocity relation does not detect myocardial rejection; and (2) neither LV fractional shortening, LV volume, nor LV mass detect rejection; and (3) central venous pressure influence wall stress values significantly.

Medium-term results of pediatric patients undergoing orthotopic heart transplantation.

To establish the medium-term results of our transplant population, we retrospectively reviewed the charts of 51 consecutive patients who underwent orthotopic heart transplantation between July 1988 and April 1995. These patients comprised two groups: group A consists of 26 patients (age 6 days to 16.4 years, median 1.4 years) with no previous heart surgery, and group B consists of 25 patients (ages 0.1 to 14.3 years, median 8.3 years), all of whom had heart surgery before undergoing transplantation. There was no difference between these groups in early or late survival rates, and neither age at transplantation nor sex was an indicator of survival. There have been 14 deaths, six early (before hospital discharge) and eight late. Early deaths have predominantly been attributed to long-term ventilation and hemodynamic instability before transplantation, and late deaths to graft coronary artery disease (n = 4), acute coronary vasculitis (n = 3), and acute cellular rejection (n = 1). Although infection has resulted in significant morbidity (57 hospital admissions), there have been no late deaths resulting from infection. Sepsis accounts for four early deaths in chronically ill patients. Orthotopic heart transplantation in the pediatric patient with and without previous heart surgery is a viable option for those with end-stage heart disease and those in whom other surgical options carry a prohibitively high mortality rate.

Successful application of the Norwood procedure for infants without hypoplastic left heart syndrome.

Although the first-stage Norwood procedure mostly has been used for hypoplastic left heart syndrome, there are other anomalies in which the Norwood procedure can be applied. Since 1991, 18 newborns without hypoplastic left heart syndrome underwent a first-stage Norwood procedure. All had a hypoplastic aortic annulus, ascending aorta, and transverse aorta. Ten had normally related great arteries: aortic atresia or aortic stenosis with inadequate left ventricle in 4, mitral atresia or stenosis in 4, and interrupted aortic arch in 2. The 8 others had double-outlet right ventricle with mitral atresia or complete transposition with a hypoplastic right ventricle. Age ranged from 2 to 77 days (median, 6 days) and weight from 2.4 to 4.4 kg (mean, 3.0 kg). The patients with interrupted aortic arch simultaneously underwent primary repair of the interruption. There were 17 hospital survivors (94%). There have been no late deaths in follow-up from 4 to 30 months (mean, 15.5 months). Thirteen children have had subsequent creation of a bidirectional Glenn shunt with takedown of the original systemic to pulmonary shunt. The 2 with interrupted aortic arch underwent a Rastelli-type biventricular repair. These results show that the Norwood procedure can be applied to infants without hypoplastic left heart syndrome who have hypoplastic aortas and excessive pulmonary blood flow with very low mortality and excellent palliation.

Follow-up of surgical correction of vascular anomalies causing tracheobronchial compression.

Between January 1977 and January 1990, 44 patients with symptomatic vascular rings/slings required surgical intervention at this center. Nineteen patients had double aortic arch (group I); 13 patients had vascular ring consisting of right aortic arch, anomalous origin of the left subclavian artery, and ligamentum arteriosus (group II); eight patients had innominate artery compression (group III); and four patients had pulmonary artery sling (group IV). Three patients had complex congenital heart defect and died secondary to it and are excluded from the study. Follow-up was obtained on 31 patients (76%). The follow-up period ranged from 0.4 years to 10.9 years, with a mean of 3.6 years. Seventy percent of the overall group were asymptomatic, and 30% of patients continued to have upper and lower respiratory symptoms on late follow-up. One third of patients in groups I and II, who underwent surgical repair, continue to have symptoms. Patients who have persistent symptoms should be further evaluated with PFTs, MRI, and bronchoscopy, and may benefit from aortopexy. Patients with innominate artery compression and pulmonary artery sling do well soon after surgery with relief of most of their symptoms.