Fetal Interventions for Congenital Heart Disease in Brazil

Fetal interventions have been performed for some congenital heart diseases. However, these procedures have not gained wide acceptance due to concerns about their efficacy and safety. The aim of this study was to report on a preliminary experience with fetal cardiac interventions in Brazil. Twenty-two cardiac interventions were performed in 21 fetuses. Thirteen fetuses had critical aortic stenosis (CAS), 4 had hypoplastic left heart syndrome (HLHS) and intact interatrial septum or small patent foramen ovale, 1 had pulmonary atresia with intact ventricular septum (IVS), and 3 had critical pulmonary stenosis (CPS). The main outcome variables evaluated were technical success and procedural complications as well as pregnancy and postnatal outcomes. Success was achieved in 20 of 22 procedures (91 %) with 1 failed aortic and 1 failed pulmonary valvuloplasties. There was 1 fetal death. No maternal complications occurred. One patient with CAS, severe mitral regurgitation, and hydrops died postnatally within 5 months of age. All patients with HLHS and restrictive atrial septum died after interventional or surgical procedures and prolonged hospitalizations. All patients with CPS/IVS survived and achieved a biventricular (BV) circulation after neonatal valvuloplasty and ductal stenting. A BV circulation was achieved in 4 of 8 patients with CAS and evolving HLHS (one still in utero), including 2 with initial borderline left ventricles (LV) in whom surgical LV overhaul was performed at 9 months of age. In this preliminary experience, the feasibility of fetal cardiac interventions and their outcomes were similar to those previously reported.     

Pathophysiology, management, and outcomes of fetal hemodynamic instability during prenatal cardiac intervention

Prenatal cardiac intervention (PCI) may favorably alter the in utero course of some congenital heart defects. In our preliminary experience with PCI, fetal hemodynamic instability (FHI) characterized by bradycardia and ventricular dysfunction was common. This study evaluated the pathophysiology, management, and short-term outcomes of FHI during PCI for aortic stenosis with evolving hypoplastic left heart syndrome (HLHS), HLHS with restrictive atrial septum, pulmonary atresia with intact ventricular septum, and hydrops due to structural heart disease. From 2000 to 2006, 83 fetuses underwent PCI, with ventricular access in 63, atrial access in 17, and both in three. FHI occurred in 37 fetuses (45%). FHI was associated with transventricular PCI (all but one case of FHI; p < 0.001) and large hemopericardium (n=9; p=0.07). Prolonged FHI was associated with severe ventricular distortion during ventricular puncture (p = 0.06). FHI was treated with resuscitation medications in 31 of 37 fetuses and resolved in all 37. Five fetuses died within 1 d of PCI: four had FHI and one had a massive hemopericardium. FHI is common and clinically important during transventricular PCI and may be caused by a ventricular reflex or reduced cardiac output from cardiac distortion during ventricular puncture. Hemopericardium may be causative in a subset of fetuses.     

The boundaries of fetal cardiac intervention: Expand or tighten?

Fetal cardiac intervention (FCI) is a relatively new and continually evolving field, and, for select cardiac defects, offers the potential to alter the progression of the disease and improve outcomes. It is a procedure that requires a collaborative effort between maternal–fetal medicine, interventional cardiology and fetal echo/ultrasound specialists, as well as fetal and maternal anesthesiologists, nursing specialists, and social workers. This article reviews the most recently reported data and advances in FCI. Currently, FCI is most frequently performed in fetuses with severe aortic stenosis (AS) with evolving hypoplastic left heart syndrome (eHLHS), established HLHS with intact or highly restrictive atrial septum (IAS), and pulmonary atresia with intact ventricular septum (PA-IVS) with evolving hypoplastic right heart syndrome (eHRHS). The goal of FCI for eHLHS and eHRHS is to promote a postnatal biventricular circulation with, theoretically, the potential for better long-term outcomes. In HLHS with IAS the aim is to improve survival. Contemporary data for FCI demonstrate limited maternal risks and improving technical success. With experience, FCI in severe AS with eHLHS has shown improved rates of biventricular outcome and early survival. Limited data for PA-IVS show promise for improving postnatal biventricular outcomes; however, for HLHS with IAS, FCI has yet to clearly demonstrate improved survival. FCI has an evolving role in the management of congenital heart defects. Ongoing analysis of disease progression, patient selection and postnatal outcomes, in conjuncture with technologic innovations and a multicenter collaborative approach, is essential as the field expands.     

Optimization of Preoperative Status in Hypoplastic Left Heart Syndrome With Intact Atrial Septum by Left Atrial Decompression and Bilateral Pulmonary Artery Bands

Hypoplastic left heart syndrome (HLHS) with intact (IAS) or highly restrictive atrial septum (RAS) has extremely poor outcomes largely related to pulmonary pathology. At birth, immediate left atrial (LA) decompression is required to remain viable, but there is a tradeoff between residual increase in LA pressure and pulmonary overcirculation, either of which exacerbates the pulmonary status. From August 2010 to April 2013, a retrospective chart review was performed on consecutive patients with a prenatal diagnosis of HLHS with IAS/RAS presenting to a single center. The management strategy was immediate LA decompression followed by placement of bilateral pulmonary artery bands (bPAB) and subsequent conventional Norwood procedure. Six patients were born with HLHS with IAS/RAS during this time period with this planned management strategy. Four patients underwent LA decompression and subsequently developed low cardiac output with pulmonary overcirculation. bPAB were used with improvement in cardiac output and pronounced diuresis. These patients all survived the Norwood and subsequent Glenn procedures and remain alive [median follow-up 2.2 years (range 11 months–2.7 years)]. Two patients did not survive with therapy being withdrawn before the Norwood procedure. It is hypothesized that a strategy of total LA decompression followed by bPAB maximizes preoperative systemic perfusion and minimizes ongoing injury to the pulmonary system. This may enhance patient candidacy for the Norwood procedure and long-term survival.     

Leftward Displacement of Septum Primum in Hypoplastic Left Heart Syndrome

Embryologic development of atrial septum primum antedates formation of the atrioventricular and semilunar valves. Leftward displacement of the superior attachment of septum primum (LDSP) has only been described in hypoplastic left heart syndrome (HLHS). This study reports the frequency of LDSP in HLHS and correlates LDSP with other echocardiographic features of HLHS. Preoperative echocardiograms for 72 consecutive patients with classic HLHS from 1996 to 2002 at Children’s Hospital of Wisconsin were reviewed. One patient was excluded for inadequate imaging. Data for the 71 patients included the following: size, location, and Doppler gradient across the atrial septal defect (ASD); location of attachment of septum primum; size and patency of the aortic valve (AoV) annulus; size and patency of the mitral valve (MV) annulus; ascending aorta diameter (AAD); and left-ventricular end diastolic dimension (LVEDD). Patients were categorized into three groups: aortic atresia/mitral atresia (AA/MA), aortic atresia/mitral stenosis (AA/MS), and aortic stenosis/mitral stenosis (AS/MS). LDSP was seen in 46 of 71 patients (64 %). By diagnostic group, 32 of 35 patients with AA/MA had LDSP (91 %) compared with 10 of 19 AA/MS patients (53 %) and 4 of 17 AS/MS patients (24 %), p < 0.05. AoV patency was seen in 4 of 46 (9 %) patients with LDSP compared with 13 of 25 (52 %) patients with normal atrial attachment, p < 0.005. Mean left heart dimensions in infants with LDSP compared with normal attachment were as follows: AoV annulus 2.24 versus 3.83 mm, AAD 2.34 versus 4.1 mm, MV annulus 3.21 versus 6.48 mm, and LVEDD 6.38 versus 13.83 mm. By two-way analysis of variance of diagnostic category versus atrial septal attachment with interaction, MV annulus and AAD were independently predicted smaller by LDSP versus normal atrial attachment, p < 0.05. Nonsignificant factors included AoV annulus, LVEDD, ASD size, and Doppler gradient. LDSP correlates with more severe maldevelopment of the left heart in patients with HLHS. Because formation of septum primum precedes development and growth of the intracardiac valves, we speculate that LDSP may be an initiating event in the development of HLHS. In addition, prenatal identification of LDSP may help direct planning of potential in utero therapies.     

Has fetal echocardiography improved the prognosis of congenital heart disease? Comparison of patients with hypoplastic left heart syndrome with and without prenatal diagnosis

BACKGROUND: As prenatal diagnosis of congenital heart disease has gained in popularity, the questions of whether prenatal diagnosis of congenital heart disease is beneficial for the patient and whether fetal echocardiography has improved the prognosis of congenital heart disease are arising. METHODS: We compared four patients with prenatally diagnosed hypoplastic left heart syndrome (HLHS) with 10 patients of non-prenatally diagnosed HLHS from the view points of (i) age at transfer to our Children's Hospital; (ii) whether the oxygen was inhaled during perinatal period; (iii) whether prostaglandin E1 was administered in the period of waiting before operation; (iv) whether the patient had ductal shock; (v) timing of operation; and (vi) surgical outcome. RESULTS: The timing of the transfer to our Children's Hospital was earlier in prenatally diagnosed group than in non-diagnosed group. Oxygen was not given to any of the patients in prenatally diagnosed group. In contrast, oxygen inhalation was given in two of 10 patients in the non-prenatally diagnosed group. Prostaglandin E1 was administrated in three of four patients in the prenatally diagnosed group and seven of 10 patients in the non-prenatally diagnosed group. In terms of ductal shock, none of the patients in prenatally diagnosed group had ductal shock. However, four of 10 patients had ductal shock in the non-prenatally diagnosed group. The median age at Norwood operation was 7 days in the prenatally diagnosed group; however, it was 19 days in non-prenatally diagnosed group. Surgical outcomes showed no significant changes between the two groups. CONCLUSIONS: Prenatal diagnosis of HLHS was surely beneficial for preventing ductal shock and for keeping the patients' preoperative condition good.     

Perioperative management in pediatric heart transplantation from 1988 to 2001: anesthetic experience in a single center

Pediatric cardiac transplantation is currently an accepted option for end-stage heart disease and congenital cardiac malformations. This report focuses on the anesthetic perioperative management in 12 yr. From 1988 to 2001 we performed 90 heart transplantations in 88 children, infants and neonates. The pediatric heart transplant program of the children's heart center at our university hospital started in June 1988 with the transplantation of a 2-yr-old boy who was suffering from congenital heart disease. Since then, 88 transplants have been performed. We divided our patients into two groups. Group 1 ranged from 1988 to 1996 and Group 2 from 1997 to 2001. The patient characteristics have not significantly changed over the years in our institution. At the time of transplantation, mean age of the patients was 2.6 +/- 4.3 yr from the period of 1988-1996 and 2.5 +/- 4.1 yr from 1997 to 2001. Since 1988, 90 transplants (Tx) in 88 patients have been performed. Two patients needed re-Tx within 2 days after the initial operation because of primary graft failure. Indications for Tx were congenital heart disease (n = 67) and cardiomyopathy (n = 21). In the subgroup of the patients suffering from congenital heart disease there were 46 with the diagnosis of HLHS, followed by endocardial fibroelastosis (n = 7); the remaining 14 patients had other complex cardiac malformations and some underwent corrective palliative cardiac surgery before Tx. Sixty-three patients were younger than 1 yr of age and only five children were older than 10 yr. Twenty-three percent of the patients on the waiting list died before Tx was possible. The overall survival rate was 79% at 1 yr and 73% at 5 and 10 yr. Infants with HLHS had a lower probability of survival after 5 yr compared with other diagnosis (69% vs. 84%). Until now 21 patients have died after Tx. The duration of anesthesia, time of CPB and the age at the time of surgery decreased over the years. It is always a challenge for the anesthesiologist to treat these patients with pulmonary hypertension as one of the most critical risks in this group of patients. The preventive therapy with vasodilators as well as the availability of mechanical assist devices before and after heart transplantation reduces the effects of transitional pulmonary hypertension and prevents the development of post-operative right heart failure.     

Current Outcomes of Hypoplastic Left Heart Syndrome With Restrictive Atrial Septum: A Single-Center Experience

Advances in the management of hypoplastic left heart syndrome (HLHS) have resulted in improved survival. However, short and long-term mortality in patients with a restrictive atrial septum remains high. All neonates diagnosed with HLHS from 2003 to 2010 at our institution were evaluated. Patients who underwent atrial septostomy within the first 72 h conformed the restrictive atrial septum group (HLHS-RS). Patients with a non-restrictive communication (HLHS-NRS) formed the control group. Outcomes and survival status were determined from review of medical records. Of the 141 newborns diagnosed with HLHS, 20 (14 %) required intervention for a restrictive atrial septum. Procedural success was achieved in 17/20 (85 %) patients. Complications occurred in ten procedures, two of which were life threatening. No procedural deaths occurred. Overall median follow up was 35.5 months (0.4–104). Initial hospitalization survival was 16/20 (80 %) for the HLHS-RS group and 114/121(94 %) for the HLHS-NRS (p = 0.028). Twenty (14 %) patients were lost to follow up and 9 (6 %) underwent heart transplant. Overall survival was 10/16 (62 %) for HLHSRS patients and 77/95 (81 %) for HLHS-NRS (p = 0.1). Survival after initial discharge was 10/12 (83 %) for the HLHS-RS group and 77/88 (87 %) for the HLHS-NRS (p = 0.67). No predictors for HLHS-RS outcome were identified. Mortality at first-stage palliation in HLHS neonates with a restrictive atrial septum remains higher than in those with an unrestrictive communication. However, survival after initial hospital discharge is similar.     

Patients with univentricular heart in early childhood: parenting stress and child behaviour

Aims: To assess perceptions of child behaviour and parenting stress among the parents of young children with hypoplastic left heart syndrome (HLHS) and other forms of functionally univentricular heart defects (UVH). Methods: As part of our prospective nation‐wide neurodevelopmental follow‐up study, the parents of 23 patients with HLHS, 14 with UVH and 46 healthy controls at the mean age of 18 months received the questionnaires Child Behavior Checklist and Parenting Stress Index. Results: The reported level of total parenting stress was significantly higher among the mothers (mean score 241 vs 205, p < 0.001) and fathers (235 vs 202, p = 0.003) of patients with HLHS compared with those of controls. The parents of patients with HLHS reported significantly more total (mean T score 52 vs 45, p = 0.005) and internalizing (51 vs 41, p < 0.001) behaviour problems than the controls, but among the syndrome scales, a significant difference was only found in somatic complaints. The parents of patients with UVH did not report more parenting stress or emotional problems than the controls. Conclusion: Hypoplastic left heart syndrome, a severe congenital heart defect, increases parenting stress. The reported emotional maladjustment in affected children might in part be owing to somatic complaints.     

Right Ventricle and Tricuspid Valve Function at Midterm After the Fontan Operation for Hypoplastic Left Heart Syndrome: Impact of Shunt Type

This study aimed to evaluate clinical outcomes including hemodynamics, right ventricle (RV) function, and tricuspid valve (TV) function in patients with hypoplastic left heart syndrome (HLHS) at midterm after completion of staged palliation based on the source of pulmonary blood flow provided at stage 1. The records of all patients with HLHS who completed Fontan palliation between 2001 and 2007 were retrospectively reviewed. The outcome variables were RV dysfunction, TV, and neo-atrioventricular (neo-AV) regurgitation (from latest echocardiogram), cardiac index (CI), pulmonary vascular resistance (PVR), pulmonary artery pressure (PAp), and right ventricular end-diastolic pressure (RVEDp) (from latest catheterization). Clinical status was obtained from medical records and by contact with the referring cardiologist if necessary. Of 118 patients undergoing a Fontan for HLHS, 116 had a fenestrated lateral tunnel and 2 had an extracardiac conduit. At the time of stage 1 palliation, 36 patients had a right ventricle-to-pulmonary artery (RV-PA) conduit, and 82 patients had a modified Blalock-Taussig shunt (mBTS). All the patients except one who died of sepsis on extracorporeal membrane oxygenation (ECMO) survived the Fontan operation and were discharged home. At a mean follow-up post-Fontan period of 28.4 months (range, 0.16-95.3 months), three patients had died (2 on the transplantation list and 1 from pulmonary vein stenosis), and one patient had the Fontan circulation taken down. No patient had a heart transplantation. A follow-up echocardiogram was performed for 115 patients (after a mean of 15.6 months for RV-PA and 32.1 months for BTS), and 66 patients underwent a post-Fontan catheterization (after a mean of 15.8 months for RV-PA and 29.3 months for BTS). The hemodynamic results for RV-PA conduit versus BTS were a CI of 3.4 ± 0.8 versus 3.4 ± 1.2, a PVR of 1.8 ± 0.7 versus 1.7 ± 0.8, a PAp of 14.3 ± 3.1 versus 14.2 ± 4.5, and an RVEDp of 7.1 ± 3.3 versus 8.9 ± 5.3. No statistically significant differences were found between shunt types regarding survival or degree of RV dysfunction or in terms of neo-AV regurgitation, CI, PVR, PAp, RVEDp, or rhythm problems. Patients in the BTS group required more tricuspid valvuloplasties and had more tricuspid regurgitation at follow-up evaluation. The patients in the RV-PA group had more PA interventions. In conclusion, the contemporary results after Fontan palliation for HLHS were excellent. At the midterm follow-up evaluation, outcomes and hemodynamic data were similar between shunt types. However, the patients in the BTS group exhibited more tricuspid regurgitation, and the patients in the RV-PA group had increased pulmonary artery interventions.     

Ductus arteriosus and fetal echocardiography: Implications for practice

The ductus arteriosus (DA) is a crucial part of the fetal circulation, both in the normal fetus and in critical congenital heart disease (CHD). It allows shunting between the pulmonary and systemic circulations. In physiological prenatal conditions, the DA lets the majority of right ventricular output bypass the fluid-filled, high-resistance lungs. The DA can cause hemodynamic compromise in the fetus and neonate when constricted or absent (in isolation or in patients with CHD) and may lead to pre- or postnatal sequelae within other systems when forming part of a vascular ring. In CHD, the DA can be interrogated by fetal echocardiography to infer information regarding severity of pulmonary outflow tract obstruction, adequacy of the sub-pulmonary ventricle to supply pulmonary blood flow, and to predict the likelihood of atrial septum restriction in transposition of the great arteries. A good understanding of the DA is crucial for fetal cardiologists.     

Early postoperative outcomes in a series of infants with hypoplastic left heart syndrome undergoing stage I palliation operation with either modified Blalock-Taussig shunt or right ventricle to pulmonary artery conduit.

OBJECTIVE: Previous publications using nonconcurrent series of patients indicate improved survival for patients with hypoplastic left heart syndrome (HLHS) undergoing stage I palliation with a right ventricle to pulmonary artery conduit (NW-RVPA) vs. a modified Blalock-Taussig shunt (NW-BT). We compared postoperative outcomes in a concurrent series of patients with HLHS undergoing an NW-BT procedure vs. NW-RVPA procedure. DESIGN: Perioperative data from 66 consecutive patients who underwent NW-BT (n = 37) or NW-RVPA (n = 29) procedures were retrospectively analyzed. SETTING: Cardiac intensive care unit in a tertiary pediatric hospital. PATIENTS: Charts were reviewed for all patients with the diagnosis of HLHS undergoing the NW-BT or NW-RVPA procedure between January 2002 and December 2003. RESULTS: Cardiopulmonary bypass time was longer in the NW-BT group than in the NW-RVPA group (152.5 +/- 52.0 vs. 134.5 +/- 36.1 mins; p = .04). Postoperative diastolic pressures were higher and the Pao2 to Fio2 ratio profiles were lower for the NW-RVPA group over the first 72 hrs. Time to sternal closure (2 [1-6] vs. 4 [2-41] days; p = .01), duration of mechanical ventilation (113 [49-386] vs. 136 [84-764] hrs; p = .01), time to establish enteral feeds (4 [2-8] vs. 5 [3-22] days; p = .01), length of intensive care unit stay (11 [7-55] vs. 15 [8-90] days; p = .04), and length of hospital stay (16 [11-67] vs. 27 [12-126] days; p = .01) were shorter in the NW-RVPA group. Postoperative mortality was not significantly different between the NW-RVPA group (7%) and NW-BT group (11%). CONCLUSION: At an experienced institution with low stage I palliation mortality for HLHS, there were no differences in early morbidity and mortality between the NW-RVPA and NW-BT procedures. The primary advantage of the NW-RVPA procedure may be faster recovery following surgery and earlier discharge from the hospital.     

胎儿先天性心脏病介入治疗进展

既往观点认为,一旦胎儿患有左心发育不良综合征(HLHS)等严重心血管畸形,结局就只能是出生后功能性单心室循环、心脏移植或中止妊娠.到目前为止,开放性胎儿心脏外科技术尚不成熟,而通过胎儿心脏介入治疗技术可以在很大程度上阻止因先天性心脏病引起的胎儿水肿、自发性流产或胎儿死亡,促进发育不良的心室重新发育,形成生后的双心室循环,重塑右室流出道梗阻胎儿的肺血管床等,改善了胎儿严重心血管畸形的预后.这些进步在很大程度上依赖于对胎儿先天性心脏病病理生理学特点的准确判断.超声技术的发展以及其他评价手段的进步可促进目前还比较有限的胎儿先天性心脏病介入治疗进一步发展.     

Pulmonary Function in Children After Surgical and Percutaneous Closure of Atrial Septal Defect

This study aimed to study differences in lung function after surgical and percutaneous atrial septal defect (ASD) closure. Several studies have demonstrated abnormalities of pulmonary function in adults and children with ASD. These abnormalities persist even a few years after correction. This study compared pulmonary function between patients who underwent ASD closure by surgery and those who had closure by device. This is the ideal pediatric population for studying changes in lung function caused by cardiopulmonary bypass or sternotomy. The 46 patients in this study were treated by percutaneous closure (group 1) or surgical closure (group 2) of ASD and then scheduled for pulmonary function testing an average of 5.8 years after ASD closure. The mean values of functional residual capacity, total lung capacity, and residual volume did not differ between the two groups. The surgical group showed a significant decrease in expiratory reserve volume (p < 0.04) and forced vital capacity (p < 0.03). Expiratory flow at 25, 50, and 75% of forced vital capacity did not differ between the two groups but was on the lower limit of normal in both groups. Percutaneous closure of ASD can minimize the side effects of surgical closure on lung function. Longitudinal lung function follow-up assessment after cardiac surgery is warranted to detect and measure restrictive abnormalities in this type of congenital heart disease and others.     

The Lateral Tunnel Fontan Procedure for Hypoplastic Left Heart Syndrome: Results of 100 Consecutive Patients

The Fontan procedure for hypoplastic left heart syndrome (HLHS) is well established. Multiple surgical techniques including extracardiac conduits and autologous tissue connections have been developed. We reviewed the results of 100 consecutive patients undergoing the lateral tunnel modification of the Fontan procedure at the University of Michigan. A cross-sectional retrospective study was performed for 100 consecutive patients identified in the University of Michigan Congenital Heart Surgery database with the diagnosis of HLHS. All patients had undergone a lateral tunnel Fontan procedure between June 2000 and August 2004. The medical record was reviewed to assess patient, procedural, and morphologic determinants of outcome. Hospital survival was 97% and intermediate-term survival was 96% with a median follow-up time of 34 months. Preoperative mean pulmonary artery pressure, right ventricular end diastolic pressure, aortic cross-clamp time, and tricuspid valve regurgitation were not associated with late right ventricular function or survival. Three patients required takedown of the lateral tunnel Fontan in the early postoperative period. A positive association was found between protein-losing enteropathy and prolonged (>2 weeks) postoperative pleural drainage (p = 0.035). No patient required cardiac transplantation or late intervention on the Fontan pathway. At the time of follow-up, 100% of patients were New York Heart Association class I or II and 90% were in normal sinus rhythm. The lateral tunnel Fontan procedure for HLHS can be performed with acceptable early and intermediate-term risk. There was a low prevalence of late rhythm disturbances and other complications. Protein-losing enteropathy and prolonged pleural drainage were associated.     

Familial Association of Congenital Left Heart Abnormalities and Sustained Fetal Arrhythmia

Hypoplastic left heart syndrome (HLHS) is the most common cause of death from heart disease in the first week of life. There are reports about familial concordance by presumed morphogenetic mechanisms of abnormal embryonic blood flow with phenotypes of varying severity. The risk of having a child with a left heart lesion after a previously affected child may be as high as 5% to 12%. We present case reports from four families in which sustained fetal arrhythmia (three ectopic atrial tachycardias and one severe bradycardia due to excessive ectopic atrial beats) was demonstrated. Within these four families a close relative of the mother (a previous child, a brother, or a nephew) had severe left heart abnormality (three with HLHS and one with severe aortic valve stenosis). The association of sustained fetal arrhythmia of ectopic atrial origin and severe left heart abnormalities could be expected to occur by chance in a very low percentage of cases. We conclude that sustained fetal atrial ectopic arrhythmia is a congenital abnormality and should be considered as a risk factor for inherited congenital heart abnormalities.     

Bronchial compression in an infant with isolated secundum atrial septal defect associated with severe pulmonary arterial hypertension

Symptomatic pulmonary arterial hypertension (PAH) in patients with isolated atrial septal defect (ASD) is rare during infancy. We report a case of isolated ASD with severe PAH in an infant who developed airway obstruction as cardiomegaly progressed. The patient presented with recurrent severe respiratory insufficiency and failure to thrive before the repair of the ASD. Echocardiography confirmed volume overload on the right side of heart and severe PAH (tricuspid regurgitation [TR] with a peak pressure gradient of 55 to 60 mmHg). The chest radiographs demonstrated severe collapse of both lung fields, and a computed tomography scan showed narrowing of the main bronchus because of an intrinsic cause, as well as a dilated pulmonary artery compressing the main bronchus on the left and the intermediate bronchus on the right. ASD patch closure was performed when the infant was 8 months old. After the repair of the ASD, echocardiography showed improvement of PAH (TR with a peak pressure gradient of 22 to 26 mmHg), and the patient has not developed recurrent respiratory infections while showing successful catch-up growth. In infants with symptomatic isolated ASD, especially in those with respiratory insufficiency associated with severe PAH, extrinsic airway compression should be considered. Correcting any congenital heart diseases in these patients may improve their symptoms.     

Exercise Performance Following Repair of Hypoplastic Left Heart Syndrome: A Comparison with Other Types of Fontan Patients

Reports of exercise performance after Fontan surgery for hypoplastic left heart syndrome (HLHS) are lacking. We compared the exercise performance of total cavopulmonary connection type (TCPC) of Fontan subjects with HLHS (group 1, n= 7) to those not requiring a Norwood procedure having a systemic right ventricle (group 2, n= 6) or a systemic left ventricle (group 3, n= 8). The subjects underwent assessment of resting pulmonary mechanics followed by maximal exercise testing with a bicycle or treadmill protocol. ECG, oxygen consumption, and carbon dioxide production were measured continuously. There was not a significant difference seen between HLHS and the comparison groups for the following parameters: maximum heart rate, maximum oxygen consumption, respiratory exchange ratio, breathing reserve, and arterial oxygen saturation at rest or exercise. Exercise performance in the TCPC type of Fontan patients was comparable regardless of ventricular morphology or surgical approach.