Hypoplastic Left Heart Syndrome Is Not a Predictor of Worse Intermediate Mortality Post Fontan.

BACKGROUND: An increasing proportion of those living with single ventricle physiology have hypoplastic left heart syndrome (HLHS). Our objective was to assess the association between HLHS and outcomes post Fontan operation. METHODS: All pediatric patients who underwent a Fontan procedure at the University of Alberta between 1996 and 2016 were included. Follow-up clinical data collected included early and late surgical or catheter reintervention, echocardiography, and long-term transplant-free survival. Characteristics were compared between those with and without HLHS, and the association between outcomes and HLHS were assessed. RESULTS: A total of 320 children (median age 3.3 years, interquartile range 2.8 to 3.9 years; 121 [43.4%] female) underwent a Fontan procedure over the course of the study. Nearly one third of subjects had HLHS (107, 33.4%). Patients with HLHS were more likely to have abnormal ventricular function (19.6% versus 7.0%, p = 0.003) and worse than mild atrioventricular valve (AVV) regurgitation (23.4 versus 9.2%, p = 0.001) preoperatively. HLHS was not predictive of in-hospital Fontan failure (odds ratio 0.82, 95% CI 0.28, 2.39), late reintervention (hazard ratio [HR] 1.08, 95% CI 0.66, 1.76), or transplant-free survival (HR 1.58, 95% CI 0.72, 3.44). Subjects with HLHS were more likely to have more than mild AVV regurgitation (31.6% versus 13.3%, p = 0.028) and abnormal ventricular function (29.8% versus 10.7%, p < 0.0001) at late follow-up. CONCLUSIONS: Patients with HLHS who survive to the Fontan procedure do no worse with the operation than those with other anatomy. Given worse late ventricular function and AVV regurgitation, equivalent survival may not persist throughout a patient's life course.

Post-operative Outcomes in Children Undergoing Fontan Palliation in a Regionalized Surgical System.

Evidence suggests that outcomes in pediatric cardiac surgery are improved by consolidating care into centers of excellence. Our objective was to determine if outcomes are equivalent in patients across a large regional referral base, or if patients from centers without on-site surgery are at a disadvantage. Since 1996, all pediatric cardiac surgery has been offered at one of two centers within the region assessed, with the majority being performed at Stollery Children's Hospital. All patients who underwent a Fontan between 1996 and 2016 were included. Follow-up data including length of stay (LOS), repeat surgical interventions, and transplant-free survival were acquired for each patient. The association between post-operative outcomes and home center was assessed using Kaplan-Meier survival analysis and Cox proportional Hazards models. 320 children (median age 3.3 years, IQR 2.8-4.0) were included; 120 (37.5%) had the surgical center as their home center. Cardiac anatomy was hypoplastic left heart syndrome in 107 (33.4%) subjects. Median LOS was 11 days (IQR, 8-17), and there were 8 in-hospital deaths. There were 17 deaths and 11 transplants over the course of follow-up. Five-year transplant-free survival was 92.5%. There was no difference in hospital re-intervention, late re-intervention, or survival by referral center (all p > 0.05). In multivariable analysis, home center was not predictive of either LOS (R 2 = -0.40, p = 0.87) or transplant-free survival (1.52, 95%CI 0.66, 3.54). In children with complex congenital heart disease, a regionalized surgical care model achieves good outcomes, which do not differ according to a patient's home base.

Non-invasive Investigations for the Diagnosis of Fontan-Associated Liver Disease in Pediatric and Adult Fontan Patients.

Fontan-associated liver disease (FALD) is a serious complication related to the chronically elevated venous pressure and low cardiac output of this abnormal circulation. However, diagnostic markers for this condition are limited. We hypothesized that specific tests for fibrosis developed for other chronic liver diseases would identify a higher prevalence of FALD than ultrasound and standard laboratory tests and that identified abnormalities would correlate with time post-Fontan. In this cross-sectional study, we assessed 19 children (average age 8.4 ± 4.3 and 5.4 ± 4.1 years post-Fontan) and 8 adults (average age 31.5 ± 8.9 and 21.1 ± 4 years post-Fontan) using standard serum laboratory investigations assessing hepatic integrity and function, the FibroTest, liver ultrasound, and transient elastography (FibroScan). In adult Fontan patients, hemoglobin, C-reactive protein, and gamma-glutamyl transpeptidase were significantly increased, and white blood cell and platelet counts were significantly decreased in comparison to the pediatric cohort. International normalized ratio was mildly elevated in both children and adults. FibroTest results were suggestive of fibrosis regardless of time post-Fontan. FibroScan measurements were significantly correlated with time post-Fontan, but the incidence of ultrasound-detected liver abnormalities was variable. No cases of hepatocellular carcinoma were identified. Abnormalities suggestive of FALD occur in both children and adults post-Fontan. Select laboratory tests, and possibly ultrasound and FibroScan in some patients, appear to have the most promise for the non-invasive detection of FALD.

Comparison of two surgical techniques for complete atrioventricular septal defect repair using two- and three-dimensional echocardiography.

Different surgical techniques for complete atrioventricular septal defect (CAVSD) repair have been described, with the double-patch technique being most frequently employed. More recently a newer technique using a modified single-patch repair has been advocated. We hypothesized that the modified single-patch technique would result in an increased incidence of the two major post-repair comorbidities, namely, distortion of the left AV valve (LAVV) leaflets and narrowing of the left-ventricular outflow tract (LVOT). We studied 14 patients with CAVSD who underwent either traditional double-patch technique [group 1 (n = 7)] or modified single-patch technique [group 2 (n = 7)]. Preoperative and immediate postoperative two-dimensional (2D) echocardiograms, as well as follow-up 2D and three-dimensional (3D) studies, were reviewed. For group 1, the median age at repair was 4.1 months with a median duration from surgical repair and last echocardiogram of 44 months. For group 2, the median age at repair was 3 months with a median duration from surgical repair and last echocardiogram of 28 months. The two groups had similar demographics and ventricular septal defect size before surgery. For the LAVV, no significant difference was observed with respect to LAVV annulus size, tenting height, and the size of the vena contracta. Furthermore, there was no significant difference in the 2D echocardiographic areas and volumes of the LVOT between pre-repair and immediate post-repair studies for both groups. At the last evaluation, although there had been growth of the LVOT in both groups, no significant difference between areas and volumes were observed. Areas of the LVOT measured by 3D echocardiography on the final study showed no significant statistical difference between both groups. There was good correlation of the areas measured by 2D and 3D echocardiography within each group. In this small group, modified single-patch technique does not appear to tether the LAVV or promote an increase in regurgitation. In the short term, LVOT growth is unaffected, and the repair does not promote LVOT obstruction. 3D echocardiography is useful for area measurements of the LVOT and showed good correlation with areas measured by assumption of the LVOT shape as determined using 2D techniques.

Folic acid fortification and the birth prevalence of congenital heart defect cases in Alberta, Canada.

BACKGROUND: Congenital heart defects (CHDs) are the most common type of congenital anomaly. The precise etiology is unknown and the development of successful primary prevention strategies is challenging. Folic acid may have a protective role; however published results have been inconsistent. This study examines the impact of mandatory folic acid fortification (FAF) on the prevalence of CHDs. METHODS: CHD cases were ascertained using the Alberta Congenital Anomalies Surveillance System, Pediatric Cardiology Clinics, Pathology, and hospital records. The birth prevalence and odds ratios (OR) of isolated CHD cases (i.e., without noncardiac anomalies) were calculated comparing pre-FAF (1995-1997) with post-FAF (1999-2002). RESULTS: The prevalence of isolated CHD cases remained relatively unchanged when pre-FAF (9.34, 95% confidence interval [CI] 8.79-9.92) was compared with post-FAF (9.41, 95% CI, 8.93-9.91). Left ventricular outflow tract obstruction (LVOTO) decreased post-FAF (OR, 0.76; 95% CI, 0.61-0.94). Coarctation of the aorta contributed to this decline (OR, 0.55; 95% CI, 0.32-0.92). Atrial septal defect (ASD) (OR, 1.42; 95% CI, 1.13-1.80) and ASD with ventricular septal defect (OR, 1.52; 95% CI, 1.10-2.10) increased post-FAF. The remaining types of CHDs were unchanged. CONCLUSION: FAF alone does not have an impact on the prevalence of CHDs as a group and the majority of selected types of CHDs in Alberta. The decrease in LVOTO, particularly coarctation of the aorta, may be due to FAF or other environmental factors. The increase in ASD and ASD with ventricular septal defect may reflect an increase in diagnosis and ascertainment.

Longer term effects of closed repair of pectus excavatum on cardiopulmonary status.

BACKGROUND: The "Nuss" repair is done for correction of moderate to severe pectus excavatum (PE). The long term cardiopulmonary and psychosocial effects of repair are uncertain. The objective of this study was to compare cardiopulmonary function and subjective evaluation of appearance and exercise tolerance pre-bar insertion with post-bar removal. METHODS: All patients underwent preoperative and post-bar (3 month) removal evaluation with complete pulmonary function tests, exercise stress testing, echocardiogram, and self-rated appearance and exercise tolerance scoring. The protocol was approved by the regional ethics board, and all families gave informed consent. RESULTS: Sixty-seven patients underwent pre and post testing. Preoperative CT index was 4.4 ± 1.3. Cardiopulmonary outcomes, standardized for height and weight, showed significant improvements in FEV-1 as (pre) 81.1 ± 17.0 vs post 89.8 ± 20.5*, FVC: 91.2 ± 18.6 vs 98.9 ± 22.9*, O2 pulse: 75.8 ± 14.4 vs 80.5 ± 18.3* (each as % predicted). Both the self-ratings of appearance (2.5 ± 0.8 vs 4.4 ± 0.5) and ability to exercise (3.3 ± 0.7 vs 4.3 ± 0.6, scale 1-5) increased significantly. (All data: mean ± St Dev, *p<0.05) CONCLUSIONS: Closed repair of PE results in improvements in pulmonary and aerobic exercise function and perceived appearance and exercise tolerance. Our data suggest that the impact on appearance and self-perceived well being is greater than the physical effect.

Congenital heart defects and major structural noncardiac anomalies in Alberta, Canada, 1995-2002.

BACKGROUND: Although the majority of congenital heart defects (CHDs) occur in isolation, a significant number occur with noncardiac anomalies. This study determined the proportion of noncardiac anomalies among CHD cases in Alberta. METHODS: Records of infants and children born in Alberta between January 1, 1995, to December 31, 2002, were searched using multiple sources of ascertainment in addition to the Alberta Congenital Anomalies Surveillance System (ACASS) (Alberta Health and Wellness, 2012). Each case was assigned to one CHD category and was further categorized into one of the following groups: isolated CHD, syndromes, chromosomal, associations and sequences, teratogens, Mendelian, neoplasia, heterotaxy, multiple minor anomalies, and multiple major anomalies. RESULTS: Of all 3751 CHD cases (prevalence 12.42/1000 total births: confidence interval, 12.03-12.83), 75% were isolated, 10% had a chromosomal etiology, and 9% had multiple major anomalies. All other categories accounted for <2% each. The most commonly associated major noncardiac anomalies were musculoskeletal (MSK) (24%) followed by anomalies of the urinary tract (14%), gastrointestinal system (GI) (11%), and central nervous system (CNS) (11%). CONCLUSIONS: This is both a population-based and clinical study using a classification scheme that could help to determine possible etiologic factors contributing to CHD. By eliminating known etiologies such as chromosomal and single gene, future studies can focus on the remainder to evaluate possible preventive measures. The most commonly associated major noncardiac anomalies involve the MSK system, followed by the urinary, GI, and CNS systems.

Congenital heart defect case ascertainment by the Alberta Congenital Anomalies Surveillance System.

BACKGROUND: Congenital heart defects (CHDs) are the most common type of congenital anomaly, with a wide range of reported birth prevalence estimates. This quality assurance study describes CHD case ascertainment by the Alberta Congenital Anomalies Surveillance System (ACASS). METHODS: ACASS data for CHD cases were compared with additional sources including the two Pediatric Cardiology clinics in Alberta, the Alberta Children's Hospital Department of Pathology, and hospital records. Cases included live births, stillbirths, and fetal deaths at less than 20 weeks' gestation born in Alberta, Canada, between 1995 and 2002. The birth prevalence of cases and chi-square linear trend analyses were calculated for specific types of heart defects for the total study period. RESULTS: The ascertainment of CHD cases by ACASS was 45%. The total prevalence of CHD cases was 5.59 per 1000 total births (TBs; 95% confidence interval [CI], 5.32-5.86) when ACASS was the only data source and increased to 12.42 per 1000 TBs (95% CI, 12.03-12.83) when all data sources were used. Although the total prevalence of CHD cases remained stable during 1995 to 2002, the prevalence of atrial septal defect (ASD) and cases with an ASD and ventricular septal defect (VSD) significantly increased. The prevalence of left ventricular outflow tract obstruction cases significantly decreased during the study period. CONCLUSIONS: Pediatric cardiology clinics are worth including as additional ascertainment sources to contribute to more accurate prevalence estimates. The significant increases of ASD and cases with both an ASD and VSD may reflect differences in diagnostic and ascertainment practices.

The registry and follow-up of complex pediatric therapies program of Western Canada: a mechanism for service, audit, and research after life-saving therapies for young children.

Newly emerging health technologies are being developed to care for children with complex cardiac defects. Neurodevelopmental and childhood school-related outcomes are of great interest to parents of children receiving this care, care providers, and healthcare administrators. Since the 1970s, neonatal follow-up clinics have provided service, audit, and research for preterm infants as care for these at-risk children evolved. We have chosen to present for this issue the mechanism for longitudinal follow-up of survivors that we have developed for western Canada patterned after neonatal follow-up. Our program provides registration for young children receiving complex cardiac surgery, heart transplantation, ventricular assist device support, and extracorporeal life support among others. The program includes multidisciplinary assessments with appropriate neurodevelopmental intervention, active quality improvement evaluations, and outcomes research. Through this mechanism, consistently high (96%) follow-up over two years is maintained.

Long term cardiopulmonary effects of closed repair of pectus excavatum.

The closed or "Nuss" repair of pectus excavatum is widely accepted for correction of moderate to severe deformities. Patients typically report significant subjective improvements in pulmonary symptoms, and short and medium term evaluations (up to 2 years with the bar in place) suggest modest improvement to cardiac function but a decrease in pulmonary function. This study examined the effects at 3 months post-bar removal of closed repair of pectus on pulmonary function, exercise tolerance and cardiac function. Patients were followed prospectively after initial evaluation for operation. All patients underwent preoperative and post-bar removal evaluation with CT scan, complete pulmonary function and exercise testing to anaerobic threshold, as well as echocardiogram. Twenty-six patients have completed the follow up protocol. Preoperative CT index was 4.5 +/- 1.3, average age at operation was 13.2 years, and average tanner stage was 3.5 +/- 0.5. At 3 months or greater follow-up post-bar removal, patients reported an improvement in subjective ability to exercise and appearance (P < 0.05 by wilcoxin matched pairs). Objective measures of FEV1, total lung capacity, diffusing lung capacity, O(2) pulse, VO(2max), and respiratory quotient all showed significant improvement compared to preoperative values, while normalized values of cardiac index at rest did not (All values normalized for height and age, comparisons P < 0.05 by student's paired t test). These results demonstrate a sustained improvement in cardiopulmonary function after bar removal following closed repair of pectus excavatum. These findings contrast with results from previous studies following the open procedure, or with the closed procedure at earlier time points; the long term physiological effects of closed repair of pectus excavatum include improved aerobic capacity, likely through a combination of pulmonary and cardiac effects.

Midterm evaluation of cardiopulmonary effects of closed repair for pectus excavatum.

BACKGROUND/PURPOSE: Since the introduction of the closed technique for repair of pectus excavatum, increasing numbers of patients are presenting for surgery. However, controversy exists regarding the effects of repair on long-term cardiopulmonary outcome. This report details the effects over time of closed repair of pectus excavatum on pulmonary function, cardiac function, exercise tolerance, and the patient's perception of appearance and subjective ability to exercise. METHODS: All patients undergoing closed repair of pectus excavatum were evaluated prospectively. Preoperative computed tomography scan, static pulmonary function studies, exercise tolerance, and echocardiographic evaluation of cardiac function were done. Studies were repeated at 3 and 21 months post-bar placement, and then 3 months after bar removal. RESULTS: Pre- and postoperative data were available for an initial 48 patients, with 11 patients completing the full evaluation after bar removal. All measures of pulmonary function including forced expiratory volume in 1 second and forced vital capacity were reduced at 3 months postoperation, with a gradual increase during follow-up; however, pulmonary function remained below normative values for patients without pectus excavatum of similar age. Cardiac function as measured by cardiac output and index was increased at 3 months postoperation and maintained thereafter. Exercise tolerance declined initially and then increased by the 21-month evaluation point and after bar removal. Patients reported a subjective improvement in the ability to exercise immediately after bar insertion. CONCLUSIONS: These results corroborate previous studies which suggested that after closed repair of pectus excavatum there is an immediate subjective improvement in the ability to exercise which is paralleled by an improvement in cardiac output. However, there is an early postoperative decline in pulmonary function which does improve over time; however, this does not reach normal values for similar weight. Further studies are needed to determine whether these results are maintained, or whether after bar removal there is a further improvement in pulmonary status. These results do support the use of the closed repair of pectus excavatum for maintaining and possibly improving cardiopulmonary function in this patient population.

Kawasaki disease, myocardial infarction and coronary artery revascularization.

Kawasaki disease (KD) is the leading cause of acquired pediatric heart disease in North America and Japan. Cardiac sequelae, such as coronary artery aneurysms and myocardial infarction, are the major causes of the morbidity and mortality associated with KD. Three case scenarios are described illustrating the wide range of clinical presentations of myocardial ischemia in children after acute KD, varying from asymptomatic to fatal myocardial infarction. In addition, the present paper provides a review of the literature on myocardial infarction in association with KD and various modalities of coronary artery revascularization in children with myocardial ischemia secondary to KD.

Nonductal dependent coarctation: a 20-year study of morbidity and mortality comparing early-to-late surgical repair.

OBJECTIVE: The objective of this study was to evaluate the effect of the timing of surgical repair of nonductal dependent coarctation on the short-term outcome. METHODS: The medical records of 76 patients, diagnosed and treated for a nonductal dependent mild-to-moderate coarctation at a tertiary care institute over a 20-year period, were retrospectively reviewed with the age at repair compared against outcome measures. Multiple logistic regression was performed to assess the timing of repair, the presence of congestive heart failure or associated cardiac defects on the outcome measures. RESULTS: The mean age of surgery for the mild-to-moderate coarctation repair was 3.1 years (range: three days to 12 years). The most common cause for referral to a pediatric cardiologist was the clinical finding of a cardiac murmur. The timing of surgical repair was not found to be a predictor of morbidity or mortality. There was no significant difference in outcome measures defined as residual hypertension, residual coarctation gradient, persistent cardiomegaly, postoperative neurological sequelae, the requirement for a second surgery or the need for balloon dilatation for residual postoperative coarctation and the need for antihypertensive medications within five years postsurgery. CONCLUSION: The timing of surgical repair in the setting of nonductal dependent, mild-to-moderate coarctation of the aorta, does not adversely affect the short term (less than 20 years) outcome in children.

Outcomes from an interprovincial program of newborn open heart surgery.

OBJECTIVES: To determine 18-month neurodevelopmental outcome of survivors of complex open heart surgery at

Cardiopulmonary effects of closed repair of pectus excavatum.

BACKGROUND/PURPOSE: Increasing numbers of patients with pectus excavatum defects are presenting for operative repair. Studies that follow-up with patients after open repair have found a decrease in pulmonary function with some improvement in cardiac output and exercise tolerance; however, these effects have not been examined systematically after closed or Nuss repair of pectus excavatum. This study examined the early postoperative effects of closed repair of pectus on pulmonary function, exercise tolerance, and cardiac function. METHODS: Patients were followed up prospectively after initial evaluation for operation. All patients underwent preoperative computed tomography (CT) scan, and pre- and postoperative (3 months) pulmonary function studies, exercise tolerance, and echocardiographic evaluation of cardiac function. RESULTS: Eleven patients underwent evaluation. Preoperative CT index was 4.1 +/- 0.9. Patients reported an improvement in subjective postoperative exercise tolerance (4.1 +/- 0.7; maximal, + 5). Pulmonary function studies (FVC and vital capacity) were significantly reduced at 3 months postsurgery: change in FVC, -0.67 +/- 0.92 L and VC, -0.5 +/- 0.72 L. Similarly, VO2 max was reduced: preoperative, 35.6 +/- 1.5 versus postoperative, 29.1 +/- 11.9 L/kg/min. Cardiac function was significantly improved postoperation (stroke volume preoperative, 61.6 +/- 25 versus 77.5 +/- 23 mL postoperative). All comparisons had a P value less than.05 by Student's paired t test. CONCLUSIONS: These results show that closed repair of pectus excavatum is associated with a subjective improvement in exercise tolerance, which is paralleled by an increase in cardiac function and a decline in pulmonary function. These findings support the use of closed repair of pectus excavatum in patients who complain of subjective shortness of breath; further study is required to delineate the long-term cardiopulmonary implications after closed repair.