Sara K. Pasquali

Coronary Artery Pattern and Outcome of Arterial Switch Operation for Transposition of the Great Arteries A Meta-Analysis

Background—Prior studies of coronary pattern and outcome after arterial switch operation (ASO) for transposition of the great arteries (TGA) have been hindered by limited statistical power. This meta-analysis assesses the effect of coronary anatomy on post-ASO mortality, both overall and adjusted for time. Methods and Results—A literature search revealed 9 independent series that reported post-ASO mortality by coronary pattern in a total of 1942 patients. Odds ratios comparing all-cause mortality in patients with usual versus variant coronary patterns were calculated and combined by use of an empirical Bayesian model. Single coronary patterns, both of which loop around the great vessels, were associated with significant mortality (OR 2.9, 95% CI 1.3 to 6.8), whereas looping patterns that arose from 2 separate ostia were not (OR 1.2, 95% CI 0.8 to 1.9). This latter group includes patients with the most common variant, circumflex from right coronary artery. Patients with an intramural coronary artery had the greatest mortality (OR 6.5, 95% CI 2.9 to 14.2). Overall, patients with any variant coronary pattern had nearly twice the mortality seen in those with the usual pattern (OR 1.7, 95% CI 1.3 to 2.4). Single ostium patterns and intramural coronary arteries remained associated with significant added mortality after adjustment for time-trend effects. Conclusions—Over the past 2 decades, patients with common coronary variants have undergone ASO without added mortality compared with those with the usual coronary pattern. Those with intramural or single coronary arteries have significant added mortality that has persisted over time.

Transplantation-Free Survival and Interventions at 3 Years in the Single Ventricle Reconstruction Trial

Background— In the Single Ventricle Reconstruction (SVR) trial, 1-year transplantation-free survival was better for the Norwood procedure with right ventricle–to–pulmonary artery shunt (RVPAS) compared with a modified Blalock-Taussig shunt (MBTS). At 3 years, we compared transplantation-free survival, echocardiographic right ventricular ejection fraction, and unplanned interventions in the treatment groups. Methods and Results— Vital status and medical history were ascertained from annual medical records, death indexes, and phone interviews. The cohort included 549 patients randomized and treated in the SVR trial. Transplantation-free survival for the RVPAS versus MBTS groups did not differ at 3 years (67% versus 61%; P=0.15) or with all available follow-up of 4.8±1.1 years (log-rank P=0.14). Pre-Fontan right ventricular ejection fraction was lower in the RVPAS group than in the MBTS group (41.7±5.1% versus 44.7±6.0%; P=0.007), and right ventricular ejection fraction deteriorated in RVPAS (P=0.004) but not MBTS (P=0.40) subjects (pre-Fontan minus 14-month mean, −3.25±8.24% versus 0.99±8.80%; P=0.009). The RVPAS versus MBTS treatment effect had nonproportional hazards (P=0.004); the hazard ratio favored the RVPAS before 5 months (hazard ratio=0.63; 95% confidence interval, 0.45–0.88) but the MBTS beyond 1 year (hazard ratio=2.22; 95% confidence interval, 1.07–4.62). By 3 years, RVPAS subjects had a higher incidence of catheter interventions (P<0.001) with an increasing HR over time (P=0.005): <5 months, 1.14 (95% confidence interval, 0.81–1.60); from 5 months to 1 year, 1.94 (95% confidence interval, 1.02–3.69); and >1 year, 2.48 (95% confidence interval, 1.28–4.80). Conclusions— By 3 years, the Norwood procedure with RVPAS compared with MBTS was no longer associated with superior transplantation-free survival. Moreover, RVPAS subjects had slightly worse right ventricular ejection fraction and underwent more catheter interventions with increasing hazard ratio over time. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00115934.

Variation in Outcomes for Benchmark Operations: An Analysis of The Society of Thoracic Surgeons Congenital Heart Surgery Database

BACKGROUND We evaluated outcomes for common operations in The Society of Thoracic Surgeons Congenital Heart Surgery Database (STS-CHSDB) to provide contemporary benchmarks and examine variation between centers. METHODS Patients undergoing surgery from 2005 to 2009 were included. Centers with greater than 10% missing data were excluded. Discharge mortality and postoperative length of stay (PLOS) among patients discharged alive were calculated for 8 benchmark operations of varying complexity. Power for analyzing between-center variation in outcome was determined for each operation. Variation was evaluated using funnel plots and Bayesian hierarchical modeling. RESULTS Eighteen thousand three hundred seventy-five index operations at 74 centers were included in the analysis of 8 benchmark operations. Overall discharge mortality was: ventricular septal defect (VSD) repair = 0.6% (range, 0% to 5.1%), tetralogy of Fallot (TOF) repair = 1.1% (range, 0% to 16.7%), complete atrioventricular canal repair (AVC) = 2.2% (range, 0% to 20%), arterial switch operation (ASO) = 2.9% (range, 0% to 50%), ASO + VSD = 7.0% (range, 0% to 100%), Fontan operation = 1.3% (range, 0% to 9.1%), truncus arteriosus repair = 10.9% (0% to 100%), and Norwood procedure = 19.3% (range, 0% to 100%). Funnel plots revealed that the number of centers characterized as outliers were VSD = 0, TOF = 0, AVC = 1, ASO = 3, ASO + VSD = 1, Fontan operation = 0, truncus arteriosus repair = 4, and Norwood procedure = 11. Power calculations showed that statistically meaningful comparisons of mortality rates between centers could be made only for the Norwood procedure, for which the Bayesian-estimated range (95% probability interval) after risk-adjustment was 7.0% (3.7% to 10.3%) to 41.6% (30.6% to 57.2%). Between-center variation in PLOS was analyzed for all operations and was larger for more complex operations. CONCLUSIONS This analysis documents contemporary benchmarks for common pediatric cardiac surgical operations and the range of outcomes among centers. Variation was most prominent for the more complex operations. These data may aid in quality assessment and quality improvement initiatives.

Association of Center Volume With Mortality and Complications in Pediatric Heart Surgery

OBJECTIVE: Previous analyses have suggested center volume is associated with outcome in children undergoing heart surgery. However, data are limited regarding potential mediating factors, including the relationship of center volume with postoperative complications and mortality in those who suffer a complication. We examined this association in a large multicenter cohort. METHODS: Children 0 to 18 years undergoing heart surgery at centers participating in the Society of Thoracic Surgeons Congenital Heart Surgery Database (2006–2009) were included. In multivariable analysis, we evaluated outcomes associated with annual center volume, adjusting for patient factors and surgical risk category. RESULTS: A total of 35 776 patients (68 centers) were included. Overall, 40.6% of patients had ≥1 complication, and the in-hospital mortality rate was 3.9%. The mortality rate in those patients with a complication was 9.0%. In multivariable analysis, lower center volume was significantly associated with higher in-hospital mortality. There was no association of center volume with the rate of postoperative complications, but lower center volume was significantly associated with higher mortality in those with a complication (P = .03 when volume examined as a continuous variable; odds ratio in centers with <150 vs >350 cases per year = 1.59 [95% confidence interval: 1.16–2.18]). This association was most prominent in the higher surgical risk categories. CONCLUSIONS: These data suggest that the higher mortality observed at lower volume centers in children undergoing heart surgery may be related to a higher rate of mortality in those with postoperative complications, rather than a higher rate of complications alone.

An empirically based tool for analyzing morbidity associated with operations for congenital heart disease

OBJECTIVE Congenital heart surgery outcomes analysis requires reliable methods of estimating the risk of adverse outcomes. Contemporary methods focus primarily on mortality or rely on expert opinion to estimate morbidity associated with different procedures. We created an objective, empirically based index that reflects statistically estimated risk of morbidity by procedure. METHODS Morbidity risk was estimated using data from 62,851 operations in the Society of Thoracic Surgeons Congenital Heart Surgery Database (2002-2008). Model-based estimates with 95% Bayesian credible intervals were calculated for each procedures average risk of major complications and average postoperative length of stay. These 2 measures were combined into a composite morbidity score. A total of 140 procedures were assigned scores ranging from 0.1 to 5.0 and sorted into 5 relatively homogeneous categories. RESULTS Model-estimated risk of major complications ranged from 1.0% for simple procedures to 38.2% for truncus arteriosus with interrupted aortic arch repair. Procedure-specific estimates of average postoperative length of stay ranged from 2.9 days for simple procedures to 42.6 days for a combined atrial switch and Rastelli operation. Spearman rank correlation between raw rates of major complication and average postoperative length of stay was 0.82 in procedures with n greater than 200. Rate of major complications ranged from 3.2% in category 1 to 30.0% in category 5. Aggregate average postoperative length of stay ranged from 6.3 days in category 1 to 34.0 days in category 5. CONCLUSIONS Complication rates and postoperative length of stay provide related but not redundant information about morbidity. The Morbidity Scores and Categories provide an objective assessment of risk associated with operations for congenital heart disease, which should facilitate comparison of outcomes across cohorts with differing case mixes.

Linking clinical registry data with administrative data using indirect identifiers: Implementation and validation in the congenital heart surgery population

BACKGROUND The use of clinical registries and administrative data sets in pediatric cardiovascular research has become increasingly common. However, this approach is limited by relatively few existing datasets, each of which contain limited data, and do not communicate with one another. We describe the implementation and validation of methodology using indirect patient identifiers to link The Society of Thoracic Surgeons Congenital Heart Surgery (STS-CHS) Database to The Pediatric Health Information Systems (PHIS) Database (a pediatric administrative database). METHODS Centers submitting data to STS-CHS and PHIS during 2004 to 2008 were included (n=30). Both data sets were limited to patients 0 to 18 years old undergoing cardiac surgery. An exact match was defined as an exact match on each of the following: date of birth, date of admission, date of discharge, sex, and center. Likely matches were defined as an exact match for all variables except ±1 day for one of the date variables. RESULTS Of 45,830 STS-CHS records, 87.4% matched to PHIS using the exact match criteria and 90.3% using the exact or likely match criteria. Validation in a subset of patients revealed that 100% of exact and likely matches were true matches. CONCLUSIONS This analysis demonstrates that indirect identifiers can be used to create high-quality link between a clinical registry and administrative data set in the congenital heart surgery population. This methodology, which can also be applied to other data sets, allows researchers to capitalize on the strengths of both types of data and expands the pool of data available to answer important clinical questions.

Corticosteroids and Outcome in Children Undergoing Congenital Heart Surgery Analysis of the Pediatric Health Information Systems Database

Background— Children undergoing congenital heart surgery often receive corticosteroids with the aim of reducing the inflammatory response after cardiopulmonary bypass; however, the value of this approach is unclear. Methods and Results— The Pediatric Health Information Systems Database was used to evaluate outcomes associated with corticosteroids in children (0 to 18 years of age) undergoing congenital heart surgery at 38 US centers from 2003 to 2008. Propensity scores were constructed to account for potential confounders: age, sex, race, prematurity, genetic syndrome, type of surgery (Risk Adjustment in Congenital Heart Surgery [RACHS-1] category), center, and center volume. Multivariable analysis, adjusting for propensity score and individual covariates, was performed to evaluate in-hospital mortality, postoperative length of stay, duration of ventilation, infection, and use of insulin. A total of 46 730 children were included; 54% received corticosteroids. In multivariable analysis, there was no difference in mortality among corticosteroid recipients and nonrecipients (odds ratio, 1.13; 95% confidence interval, 0.98 to 1.30). Corticosteroids were associated with longer length of stay (least square mean difference, 2.18 days; 95% confidence interval, 1.62 to 2.74 days), greater infection (odds ratio, 1.27; 95% confidence interval, 1.10 to 1.46), and greater use of insulin (odds ratio, 2.45; 95% confidence interval, 2.24 to 2.67). There was no difference in duration of ventilation. In analysis stratified by RACHS-1 category, no significant benefit was seen in any group, and the association of corticosteroids with increased morbidity was most prominent in RACHS-1 categories 1 through 3. Conclusion— In this observational analysis of children undergoing congenital heart surgery, we were unable to demonstrate a significant benefit associated with corticosteroids and found that corticosteroids may be associated with increased morbidity, particularly in lower-risk patients. # Clinical Perspective {#article-title-43}Background— Children undergoing congenital heart surgery often receive corticosteroids with the aim of reducing the inflammatory response after cardiopulmonary bypass; however, the value of this approach is unclear. Methods and Results— The Pediatric Health Information Systems Database was used to evaluate outcomes associated with corticosteroids in children (0 to 18 years of age) undergoing congenital heart surgery at 38 US centers from 2003 to 2008. Propensity scores were constructed to account for potential confounders: age, sex, race, prematurity, genetic syndrome, type of surgery (Risk Adjustment in Congenital Heart Surgery [RACHS-1] category), center, and center volume. Multivariable analysis, adjusting for propensity score and individual covariates, was performed to evaluate in-hospital mortality, postoperative length of stay, duration of ventilation, infection, and use of insulin. A total of 46 730 children were included; 54% received corticosteroids. In multivariable analysis, there was no difference in mortality among corticosteroid recipients and nonrecipients (odds ratio, 1.13; 95% confidence interval, 0.98 to 1.30). Corticosteroids were associated with longer length of stay (least square mean difference, 2.18 days; 95% confidence interval, 1.62 to 2.74 days), greater infection (odds ratio, 1.27; 95% confidence interval, 1.10 to 1.46), and greater use of insulin (odds ratio, 2.45; 95% confidence interval, 2.24 to 2.67). There was no difference in duration of ventilation. In analysis stratified by RACHS-1 category, no significant benefit was seen in any group, and the association of corticosteroids with increased morbidity was most prominent in RACHS-1 categories 1 through 3. Conclusion— In this observational analysis of children undergoing congenital heart surgery, we were unable to demonstrate a significant benefit associated with corticosteroids and found that corticosteroids may be associated with increased morbidity, particularly in lower-risk patients.

Differential Case Ascertainment in Clinical Registry Versus Administrative Data and Impact on Outcomes Assessment for Pediatric Cardiac Operations

BACKGROUND Administrative datasets are often used to assess outcomes and quality of pediatric cardiac programs; however their accuracy regarding case ascertainment is unclear. We linked patient data (2004-2010) from the Society of Thoracic Surgeons Congenital Heart Surgery (STS-CHS) Database (clinical registry) and the Pediatric Health Information Systems (PHIS) database (administrative database) from hospitals participating in both to evaluate differential coding/classification of operations between datasets and subsequent impact on outcomes assessment. METHODS Eight individual benchmark operations and the Risk Adjustment in Congenital Heart Surgery, version 1 (RACHS-1) categories were evaluated. The primary outcome was in-hospital mortality. RESULTS The cohort included 59,820 patients from 33 centers. There was a greater than 10% difference in the number of cases identified between data sources for half of the benchmark operations. The negative predictive value (NPV) of the administrative (versus clinical) data was high (98.8%-99.9%); the positive predictive value (PPV) was lower (56.7%-88.0%). Overall agreement between data sources in RACHS-1 category assignment was 68.4%. These differences translated into significant differences in outcomes assessment, ranging from an underestimation of mortality associated with truncus arteriosus repair by 25.7% in the administrative versus clinical data (7.01% versus 9.43%; p = 0.001) to an overestimation of mortality associated with ventricular septal defect (VSD) repair by 31.0% (0.78% versus 0.60%; p = 0.1). For the RACHS-1 categories, these ranged from an underestimation of category 5 mortality by 40.5% to an overestimation of category 2 mortality by 12.1%; these differences were not statistically significant. CONCLUSIONS This study demonstrates differences in case ascertainment between administrative and clinical registry data for children undergoing cardiac operations, which translated into important differences in outcomes assessment.

Congenital Heart Surgery Outcomes in Down Syndrome: Analysis of a National Clinical Database

OBJECTIVE: We describe patient characteristics and postoperative morbidity and mortality rates for patients with Down syndrome undergoing congenital heart disease surgery. METHODS: This retrospective cohort study used the Society of Thoracic Surgeons Congenital Heart Surgery Database to compare patient characteristics and postoperative outcomes for patients (0–18 years) with or without Down syndrome who underwent surgery in 2000–2008. RESULTS: A total of 45 579 patients (4350 patients with Down syndrome and 41 229 without Down syndrome) were included (median age: 7 months [interquartile range [IQR]: 47 days to 4 years]; 56% male). Patients with Down syndrome were younger at surgery, with the exception of those undergoing tetralogy of Fallot repair or atrioventricular septal defect repair. Mortality rates for patients with or without Down syndrome did not differ significantly. Lengths of stay were prolonged for patients with Down syndrome undergoing atrial septal defect closure (median: 4 days [IQR: 3–5 days] vs 3 days [IQR: 2–4 days]; P < .0001), ventricular septal defect closure (median: 5 days [IQR: 4–8 days] vs 4 days [IQR: 3–6 days]; P < .0001), or tetralogy of Fallot repair (7 days [IQR: 5–10 days] vs 6 days [IQR: 5–9 days]; P < .001) and were associated with postoperative respiratory and infectious complications. Patients with Down syndrome undergoing ventricular septal defect closure had a higher rate of heart block requiring pacemaker placement (2.9% vs 0.8%; P < .0001). CONCLUSION: In this large, contemporary cohort, Down syndrome did not confer a significant mortality risk for the most common operations; however, postoperative morbidity remained common.

Perioperative Methylprednisolone and Outcome in Neonates Undergoing Heart Surgery

BACKGROUND: Recent studies have called into question the benefit of perioperative corticosteroids in children undergoing heart surgery, but have been limited by the lack of placebo control, limited power, and grouping of various steroid regimens together in analysis. We evaluated outcomes across methylprednisolone regimens versus no steroids in a large cohort of neonates. METHODS: Clinical data from the Society of Thoracic Surgeons Database were linked to medication data from the Pediatric Health Information Systems Database for neonates (≤30 days) undergoing heart surgery (2004–2008) at 25 participating centers. Multivariable analysis adjusting for patient and center characteristics, surgical risk category, and within-center clustering was used to evaluate the association of methylprednisolone regimen with outcome. RESULTS: A total of 3180 neonates were included: 22% received methylprednisolone on both the day before and day of surgery, 12% on the day before surgery only, and 28% on the day of surgery only; 38% did not receive any perioperative steroids. In multivariable analysis, there was no significant mortality or length-of-stay benefit associated with any methylprednisolone regimen versus no steroids, and no difference in postoperative infection. In subgroup analysis by surgical-risk group, there was a significant association of methylprednisolone with infection consistent across all regimens (overall odds ratio 2.6, 95% confidence interval 1.3–5.2) in the lower-surgical-risk group. CONCLUSIONS: This multicenter observational analysis did not find any benefit associated with methylprednisolone in neonates undergoing heart surgery and suggested increased infection in certain subgroups. These data reinforce the need for a large randomized trial in this population.