Interrupted aortic arch type B in trisomy 21: repair with carotid artery interposition.

A 21-year-old man with Trisomy 21 was diagnosed with interrupted aortic arch type B and perimembranous ventricular septal defect in the newborn period. He underwent carotid artery interposition and pulmonary artery banding with subsequent debanding and closure of the ventricular septal defect. Cardiac catheterization 20 years later demonstrated good "carotid arch" growth with no residual arch obstruction. Carotid artery interposition provided good curative repair for arch obstruction at late follow-up in this patient.

Reconstruction of stenotic or occluded iliofemoral veins and inferior vena cava using intravascular stents: re-establishing access for future cardiac catheterization and cardiac surgery.

OBJECTIVES: The study evaluated the safety and efficacy of stent reconstruction of stenotic/occluded iliofemoral veins (IFV) and inferior vena cava (IVC). BACKGROUND: Patients with congenital heart defects and stenotic or occluded IFV/IVC may encounter femoral venous access problems during future cardiac surgeries or catheterizations. METHODS: Twenty-four patients (median age 4.9 years) underwent implantation of 85 stents in 22 IFV and 6 IVC. Fifteen vessels were severely stenotic and 13 were completely occluded. Although guide wires were easily passed across the stenotic vessels, occluded vessels required puncture through the thrombosed sites using a stiff wire or transseptal needle. Once traversed, the occluded site was dilated serially prior to stent implantation. RESULTS: Following stent placement, the mean vessel diameter increased from 0.9 +/- 1.6 to 7.4 +/- 2.6 mm (p < 0.05). Twenty-one of 28 vessels had long segment stenosis/occlusion requiring two to seven overlapping stents. Repeat catheterizations were performed in seven patients (9 stented vessels) at mean follow-up of 1.6 years. Seven vessels remained patent with mean diameter of 6.4 +/- 2.0 mm. Two vessels were occluded, but they were easily recanalized and redilated. Echocardiographic follow-up in two patients with IVC stents demonstrated wide patency. In four additional patients, a stented vessel was utilized for vascular access during subsequent cardiac surgery (n = 3) and endomyocardial biopsy (n = 1). Therefore, 13 of 15 stented vessels (87%) remained patent at follow-up thus far. CONCLUSIONS: Stenotic/obstructed IFV and IVC may be reconstructed using stents to re-establish venous access to the heart for future cardiac catheterization and/or surgeries.

Transcatheter closure of surgical shunts in patients with congenital heart disease.

The aim of this study was to review contemporary techniques, devices, and results of transcatheter occlusion of surgical shunts in 2 pediatric cardiac programs. Closure of superfluous surgical shunts may reduce cardiac work and risk of endocarditis. Previous studies have shown that transcatheter closure of shunts is feasible, but have not demonstrated acceptable efficacy or safety. In addition, the performance of new techniques and devices has not been reviewed. Between 1993 and 1998, 18 patients with congenital heart disease underwent transcatheter closure of 19 Blalock-Taussig shunts. Detachable and standard Gianturco coils and Gianturco-Grifka vascular occlusion devices were employed. All 19 shunts had complete closure. Eight shunts had initial placement of detachable coils. Five shunts had stents placed that bridged the pulmonary end of the shunts. These 5 and 4 additional shunts had closure by standard coils. Two shunts were closed with Gianturco-Grifka devices. There were no complications, no embolizations, and no requirement for surgery precipitated by the procedures. This review of contemporary techniques, devices, and results suggests that transcatheter occlusion of surgical shunts is effective and safe.

Atresia of the proximal right coronary artery in association with coronary artery fistula.

A 2-year-old boy presented for evaluation of a systolic murmur. Echocardiogram demonstrated dilated left main and right coronary arteries. Selective injection of the left coronary artery confirmed dilation of the left main and anterior descending coronary arteries. The left anterior descending coronary artery subsequently filled the mid portion of the right coronary artery retrograde, which emptied into a blind fistula. The orifice of the right coronary artery was atretic, with no filling from the aortic root or the fistula.

Stenting of stenosed aortopulmonary collaterals and shunts for palliation of pulmonary atresia/ventricular septal defect.

Patients with unrepaired pulmonary artery atresia and ventricular septal defect (PA/VSD) depend on aortoplumonary collaterals and surgically created shunts for pulmonary blood flow. These vessels frequently develop stenoses with time, leading to hypoperfusion of lung segments and systemic hypoxemia. The purpose of this article is to describe catheter palliation of hypoxemic patients with PA/VSD who were not candidates for surgical repair. We present our experience with stent implantation for stenosis of aortopulmonary collaterals and shunts in these patients. Three patients with hypoplastic pulmonary arteries underwent stent placement in aortopulmonary collateral arteries (APCAs) or their shunts. Technical aspects of the interventional catheterization procedure are discussed in detail. Case 1 underwent placement of five stents in collateral vessels and one stent in the Blalock-Taussig shunt (BT) with dramatic increase in vessel size and improvement in saturations from 70% to 89%. Case 2 underwent placement of two overlapping stents in a collateral vessel with an increase in diameter of the collateral vessel from 2.3 to 6 mm and an improvement in saturation from 68% to 88%. Case 3 underwent placement of three overlapping stents in a BT shunt with an increase in diameter of the shunt from 2.2 to 6.6 mm and an improvement in saturation from 71% to 89%. All three patients had excellent clinical improvement and stable saturation at follow-up. Stent placement for maintaining patency of APCAs and aortopulmonary shunts is feasible and safe.

Light touch contribution to balance in normal bipedal stance.

It has previously been shown that light contact with the finger tip on a fixed surface reduces centre of pressure (CoP) fluctuations in the frontal plane when standing in an unstable posture with the feet in line (tandem Romberg stance). Positive cross-correlations between horizontal finger forces and CoP fluctuations with finger forces exhibiting a phase lead suggest the hand provides sensory input for postural stability. The present study investigates whether this is the case for normal posture. We report reduced CoP fluctuations in the sagittal plane when light touch is permitted during normal bipedal stance. Moreover, we find positive crosscorrelations between finger tip forces and CoP fluctuations which are of similar magnitude and phase lag to those observed in tandem Romberg stance. This shows the utility of hand touch input for regulation of normal upright posture as well as inherently unstable postures such as tandem Romberg.

Aortic root dilation after the Ross procedure.

This study evaluated changes in neoaortic root geometry in patients who underwent the Ross procedure. Serial postoperative echocardiographic measurements of the neoaortic root indexed to the square root of body surface area (centimeters divided by meters) were obtained from 30 patients (age range 3.1 to 31.4 years) and compared with paired preoperative and immediate postoperative values. Normal aortic root diameter Z scores were derived from root dimensions obtained from 217 healthy controls. Compared with preoperative values, an immediate stretch of the neoaortic versus pulmonary root (annulus and sinuses of valsalva) was observed at a mean follow-up period of 1 week. Additional aortic annular dilation from baseline prehospital discharge values was observed at 2 to 12 months (baseline vs follow-up annulus Z score: 1.4 vs 2.6, p <0.01, n = 16) and at 16 to 33 months follow-up (0.8 vs 2.0, p <0.05, n = 12). In a similar fashion, there was additional enlargement of the aortic sinus from its stretched state at hospital discharge at 2 to 12 months (baseline vs follow-up sinus Z score: 2.0 vs 3.3, p <0.01, n = 17) and at 16 to 33 months (1.7 vs 3.0, p <0.01, n = 13). There were no differences in root size between 2 to 12 and 16 to 33 months after surgery. There was a decrease in left ventricular size with no alteration in blood pressure or degree of aortic valve regurgitation. Thus, aortic root dilation occurs up to the first year after the Ross procedure but does not appear to progress beyond this time.

Frequent detection of escape from cytotoxic T-lymphocyte recognition in perinatal human immunodeficiency virus (HIV) type 1 transmission: the ariel project for the prevention of transmission of HIV from mother to infant.

Host immunologic factors, including human immunodeficiency virus (HIV)-specific cytotoxic T lymphocytes (CTL), are thought to contribute to the control of HIV type 1 (HIV-1) replication and thus delay disease progression in infected individuals. Host immunologic factors are also likely to influence perinatal transmission of HIV-1 from infected mother to infant. In this study, the potential role of CTL in modulating HIV-1 transmission from mother to infant was examined in 11 HIV-1-infected mothers, 3 of whom transmitted virus to their offspring. Frequencies of HIV-1-specific human leukocyte antigen class I-restricted CTL responses and viral epitope amino acid sequence variation were determined in the mothers and their infected infants. Maternal HIV-1-specific CTL clones were derived from each of the HIV-1-infected pregnant women. Amino acid substitutions within the targeted CTL epitopes were more frequently identified in transmitting mothers than in nontransmitting mothers, and immune escape from CTL recognition was detected in all three transmitting mothers but in only one of eight nontransmitting mothers. The majority of viral sequences obtained from the HIV-1-infected infant blood samples were susceptible to maternal CTL. These findings demonstrate that epitope amino acid sequence variation and escape from CTL recognition occur more frequently in mothers that transmit HIV-1 to their infants than in those who do not. However, the transmitted virus can be a CTL susceptible form, suggesting inadequate in vivo immune control.

Laboratory and clinical evaluation of two glucose meters for the neonatal intensive care unit.

OBJECTIVE: To evaluate the analytical and clinical performance of the One Touch II and Advantage glucose meters for use in neonatal specimens. DESIGN AND METHODS: For the laboratory evaluation, a total of 96 umbilical cord whole blood specimens were analyzed on the One Touch II and/or Advantage meters. Samples were centrifuged after analysis on the meters and plasma glucose was determined on the Hitachi 917. For the clinical evaluation, a total of 64 infants had specimens analyzed on each of the meters as well as on the laboratory analyzer. RESULTS: In the laboratory and clinical evaluations, both meters correlated well (r > 0.9, p < 0.001) with the plasma values for the Hitachi 917. However, the mean difference between the Advantage and Hitachi 917 was lower than that of the One Touch II in both the laboratory (-0.23 vs -0.64 mmol/L) and the clinical evaluations (-0.08 vs -0.60 mmol/L). 53.1% of One Touch and 26.6% of Advantage results from the clinical study had a discrepancy of > 0.5 mmol/L from the laboratory value. CONCLUSIONS: For neonatal specimens, glucose meters must have good low end precision, sensitivity and accuracy, In this study, the Advantage meter had fewer discordant results and better correlation with the Hitachi 917. Overall, nursing and laboratory staff preferred the performance and characteristics of the Advantage meter.

Development of superior vena cava to pulmonary vein fistulae following modified Fontan operation: case report of a rare anomaly and embolization therapy.

A patient with double inlet single ventricle, L-transposition of the great arteries, and atrioventricular valve regurgitation developed progressive heart failure necessitating modified Fontan operation at 16 months of age. The procedure included replacement of the atrioventricular valve and pacemaker insertion. Eight years following the operation, the patient developed progressive cyanosis. Catheterization confirmed the presence of fistulae from the superior vena cava and innominate vein to the pulmonary veins as the cause of cyanosis. Coil embolization of several fistulae was performed successfully at catheterization. Contributing factors for fistula formation in Fontan patients are discussed, and therapy is reviewed.

Arch growth after staged repair of interrupted aortic arch using carotid artery interposition.

BACKGROUND: Between 1980 and 1990, our practice was to perform carotid artery interposition as part of a staged repair of interrupted aortic arch with various associated cardiac defects. METHODS: This procedure was used in 16 patients with IAA type B. The median age at operation was 4.5 days and the median weight, 3.2 kg. Ten of the patients had an associated ventricular septal defect. Six more had complex anatomy. There were two death at carotid interposition, two interim deaths, and two deaths after intracardiac repair. Preoperative echocardiographic and angiographic studies were compared with postoperative studies in 11 survivors of arch repair to assess sequential growth of the interposed carotid artery. Measurements of the carotid artery were normalized to the descending aorta. RESULTS: Preoperatively, the left carotid artery had a median diameter of 3.7 mm and was 42.9% of the descending aortic diameter. Postoperative studies performed at a median age of 5.7 months disclosed that the interposed carotid artery had grown to a median diameter of 7.0 mm and was 69.6% of the diameter of the descending aorta (normal > or = 81%). On follow-up at a median time of 4 years, 6 of 9 patients have no gradient by blood pressure measurements or echocardiographic Doppler studies, and 3 have modest gradients. No patient has required revision of the arch repair. CONCLUSIONS: Survival is good after carotid artery interposition for interrupted aortic arch and growth of the carotid artery approaches that of a normal arch. Carotid artery interposition is a viable alternative for repair of this lesion should primary definitive repair not be feasible.

Maternal HIV-1 viral load and vertical transmission of infection: the Ariel Project for the prevention of HIV transmission from mother to infant.

Most HIV-1 infections of children result from mother-to-infant transmission, which may occur perinatally or postnatally, as a consequence of breast feeding. In this study, the influence of maternal viral load on transmission of infection to infants from non-breast-feeding mothers was examined using samples of plasma and peripheral blood mononuclear cells (PBMCs) collected at several time points during pregnancy and the 6-month period after delivery. These samples were analyzed by several quantitative methods, including virus cultures of PBMCs and polymerase chain reaction (PCR) assays for HIV-1 RNA in plasma and DNA in PBMCs. The risk of transmission increased slightly with a higher viral load, but transmission and nontransmission occurred over the entire range of values for each assay. No threshold value of virus load was identified which discriminated between transmitters and nontransmitters. We also noted a significant rise in viral load and a decline in CD4+ lymphocytes in the six months after delivery. These findings suggest that a high maternal viral load is insufficient to fully explain vertical transmission of HIV-1. Additional studies are needed to examine the post-partum increase in viremia.

Bidirectional cavopulmonary anastomosis with intracardiac repair.

BACKGROUND: Patients with hypoplasia of the right ventricle and tricuspid valve have historically undergone a total cavopulmonary connection or a two-ventricle repair with atrial fenestration. METHODS: We reviewed our experience with 9 patients with hypoplasia of the right ventricle and tricuspid valve who underwent a bidirectional cavopulmonary anastomosis with intracardiac repair. Patient diagnoses included pulmonary atresia with intact ventricular septum (n = 3); hypoplastic right ventricle and tricuspid valve with atrial septal defect, ventricular septal defect, and right ventricular outflow tract obstruction (n = 3); unbalanced atrioventricular canal defect (n = 1); inlet ventricular septal defect with coarctation (n = 1); and tricuspid stenosis with atrial septal defect (n = 1). RESULTS: The median age at operation was 36 months. There was hypoplasia of the right ventricle and tricuspid valve in all patients. The tricuspid valve measured 56.5% of normal (range, 43.6% to 70.4%) by echocardiography, and the median ratio of the tricuspid valve to the mitral valve was 0.67 (range, 0.54 to 0.82). At operation, the median tricuspid valve annulus diameter was 65.6% of published autopsy normals (range, 57.8% to 78.5%) with a median Z value of -3.8 (range, -6.6 to -2.1). All patients survived operation. At a median follow-up of 16 months, 5 patients are asymptomatic, and 2 have occasional early-morning periorbital edema. Two patients are on a regimen of diuretics, 1 of whom is also taking an unloading agent. The patient with unbalanced atrioventricular canal died suddenly at home 6 months postoperatively. CONCLUSIONS: Bidirectional cavopulmonary anastomosis with intracardiac repair may avoid the long-term complications associated with the Fontan modifications and eliminates the need of atrial fenestration in most instances. This operation should be considered for select patients with hypoplasia of the right ventricle and tricuspid valve.

Enhanced resting left ventricular filling in patients with successful coarctation repair and exercise-induced hypertension.

M-mode and Doppler echocardiographic analyses of left ventricular (LV) shortening and filling were performed in 50 patients who underwent coarctectomy (median follow-up 9.5 years) and in 16 athletes in a control group before an exercise stress test with upright bicycle ergometry was performed. Thirty-two of 50 patients and 18 of 50 patients had a normotensive and hypertensive response to exercise, respectively. Preexercise echocardiographic data were compared among the control, normotensive, and hypertensive patient groups. LV peak filling rates (dD/dt, diastole) were increased in the hypertensive group (18.3 +/- 3.5) compared with those in the normotensive group (14.4 +/- 3.2; p < 0.001) and the control group (13.6 +/- 2.8; p < 0.001). LV shortening was enhanced in the coarctectomy group compared with that in the control group. A higher aortic isthmus Doppler gradient at peak exercise was not found in the hypertensive group compared with that in the normotensive group. Therefore patients with successful coarctectomy in childhood have enhanced LV shortening and relaxation at rest. Demonstration of enhanced LV peak filling rates may help identify patients at risk for exercise-induced hypertension.

A child with cardiogenic shock and supraventricular tachycardia presenting in normal sinus rhythm.

We report a case of an infant who presented in profound cardiovascular collapse with a normal sinus rhythm initially. A diagnosis of supraventricular tachycardia (SVT) was established only after hemodynamic stabilization. The possibility of SVT being masked because of severe metabolic derangements and/or painful therapeutic procedures should be kept in mind when managing cardiogenic shock in children. Such a consideration is of practical significance in planning therapy, such as the avoidance of digitalis in a patient with Wolf-Parkinson-White syndrome.

Balance evaluation in hemiparetic stroke patients using lateral forces applied to the hip.

A technique for assessing balance that involves applying predictable controlled forces to the hips is described. Impairments in hemiparetic stroke patients' balance were documented by comparing their hip movements during and after a push with those of control subjects of similar age. Stroke patients swayed further and took longer to stabilize hip position than did the control subjects. The disturbance to stroke patients' balance caused by the termination of lateral force caused them more difficulty than did the onset of the force. Differences between stroke patients' involved and noninvolved sides were more pronounced on release from a push than at its onset. The implications of the findings for the assessment and treatment of balance after stroke are discussed.

Augmented norepinephrine and renin output in response to maximal exercise in hypertensive coarctectomy patients.

To evaluate a possible neural or renal contribution to the hypertension that occurs in some patients following coarctation of aorta repair, 35 patients underwent graded bicycle exercise with serial measurements of plasma norepinephrine concentrations and plasma renin activity. Sixteen patients with coarctectomy who had systolic or diastolic hypertension at peak exercise were compared with 19 normotensive patients with coarctectomy. The average time interval between coarctation repair and study was significantly longer (p less than 0.05) in the hypertensive group than in the normotensive patients (12.8 +/- 4.8 versus 8.7 +/- 2.2 years). The heart rate response to exercise was similar for both patient groups. The systolic blood pressure in the hypertensive group was higher than in the normotensive group at rest in the supine and upright positions and at 5 minutes of recovery, in addition to peak exercise, and the diastolic blood pressure was increased at peak exercise. Plasma norepinephrine concentrations were significantly higher at peak exercise and during recovery in the hypertensive group than in the normotensive patients. Plasma renin activity was also significantly higher in the hypertensive group at peak exercise. These data suggest that patients with coarctectomy who have a hypertensive response to exercise have an augmented sympathetic nervous system output and increased plasma renin activity that may lead to peripheral vasoconstriction at peak exercise and that may contribute to the development of their hypertension.

Down's syndrome, complete atrioventricular canal, and pulmonary vascular obstructive disease.

We reviewed our experience over a 10-year period to determine whether children with Down's syndrome and complete atrioventricular canal develop pulmonary vascular obstructive disease earlier than children with normal chromosomes and this defect. Comparisons were made between Down's syndrome and normal chromosome children regarding (1) pulmonary blood flow and pulmonary vascular resistance at initial catheterization, (2) operability as related to elevation in pulmonary vascular resistance, and (3) age at diagnosis of fixed pulmonary vascular obstructive disease. The 45 patients with Down's syndrome catheterized under 1 year of age had a lower mean pulmonary blood flow (3.2 versus 5.7; p = 0.0001) and higher mean pulmonary vascular resistance (8.3 versus 4.6 Wood units.m2; p = 0.0003) than their 34 normal chromosome counterparts. When all ages were included, 38 of 81 (47%) of the children with Down's syndrome and 32 of 40 (80%) of the normal children were considered operable. Non-Down's syndrome patients who had operations had a higher pulmonary blood flow (5.8 versus 3.3; p = 0.004) and lower pulmonary vascular resistance (3.6 versus 6.0 Wood units.m2; p = 0.005) than Down's syndrome patients. Of the 34 patients who did not have operations because of pulmonary vascular obstructive disease, 31 had Down's syndrome. In 10 of 81 children with Down's syndrome, fixed pulmonary vascular obstructive disease was diagnosed before the age of 1 year, while this was found in none of 40 normal children. Our data demonstrate that Down's syndrome patients with complete atrioventricular canal have a greater degree of elevation of pulmonary vascular resistance in the first year of life and more rapid progression to fixed pulmonary vascular obstructive disease than children with normal chromosomes.

Intracardiac teratoma in a newborn.

Primary tumors of the heart are infrequent at all ages. We present a newborn with hypoxia and a heart murmur, in whom an echocardiogram revealed a large tumor filling the right ventricle and the pulmonary annulus. To maintain pulmonary blood flow, the patency of the ductus arteriosus was achieved by infusion of prostaglandin E1. Successful surgical resection was accomplished. The pathological examination was characteristic of a benign teratoma. The patient remains asymptomatic and has shown no evidence of recurrence of the tumor during a follow-up period of 34 months. This represents the eleventh case of intracardiac teratoma and only the fourth case to undergo successful surgical resection.