Abstract
Objectives
Right ventricle-to-pulmonary artery conduits are a mainstay of treatment for patients with congenital heart defects. We investigated the association of underlying genetic abnormalities with conduit failure and hypothesized that 22q11.2 deletion syndrome was associated with shorter time to failure.
Methods
We conducted a single-center retrospective cohort study at the Children's Hospital of Philadelphia. Patients who underwent right ventricle-to-pulmonary artery conduit placement as part of a biventricular repair at 0 to 24 months of age between January 2010 and June 2020 were included. The primary exposure of interest was diagnosis of 22q11.2 deletion syndrome, and the outcome was time to conduit failure. The statistical analysis used cumulative incidence function with the Gray test and cause-specific Cox regression to account for competing risk.
Results
In total, 143 patients met inclusion criteria, of whom 65 experienced conduit failure in the study period. The median time to failure was 89 months (7.4 years). Use of pulmonary homograft was independently associated with lower risk of conduit failure (hazard ratio, 0.29; confidence interval, 0.11-0.77, P = .01) and small conduit size was associated with greater risk of conduit failure (hazard ratio, 3.99, confidence interval, 1.69-9.41, P = .002) during the first 24 months. Presence of 22q11.2 deletion syndrome, age at initial surgery, and diagnosis of truncus arteriosus were not associated with conduit failure.
Conclusions
Although 22q11.2 deletion syndrome and other genetic syndromes were not associated with conduit failure, conduit size and type were the most important factors associated with conduit longevity and should be taken into account when planning surgical repair.
Key Words: congenital heart disease, pulmonary artery conduit, conduit failure, 22q.11.2 deletion syndrome (DiGeorge syndrome), children
Graphical Abstract
Cumulative incidence function of conduit failure with or without 22q11.2 deletion syndrome.
Central Message.
Conduit size and type were associated with conduit longevity and should be taken into account when planning surgical repair, whereas genetic syndromes did not affect conduit longevity.
Perspective.
Right ventricle-to-pulmonary artery conduits are a mainstay of treatment for many patients born with congenital heart defects, particularly conotruncal lesions. Few studies have investigated how genetic syndromes may impact conduit longevity. This study seeks to investigate the effect of 22q11.2 deletion syndrome on conduit longevity.
Right ventricle-to-pulmonary artery conduits (RV-PACs) are commonly used to provide pulmonary blood flow in congenital heart defects such as tetralogy of Fallot (TOF), truncus arteriosus, and for surgeries such as the Ross, Yasui, Rastelli, and Nikaidoh procedures.1 These conduits have variable longevity and often require multiple reinterventions over the years after the initial operation. RV-PAC deterioration occurs because of progressive conduit stenosis and/or regurgitation, calcification, or conduit size mismatch from somatic growth. RV-PAC failure remains a significant cause of morbidity and mortality for these patients.2
Previous studies have attempted to delineate factors that influence the longevity of RV-PAC in patients with congenital heart disease.2, 3, 4, 5, 6 Poynter and colleagues,3 reporting on a Congenital Heart Surgeon's Society cohort, found that overall conduit durability was 53% at 8 years, with larger conduits and the use of pulmonary homografts or xenografts being the only risk factors that impacted conduit longevity. Other studies have similarly demonstrated improved outcomes with xenograft conduits such as Contegra,7 but conflicting data exist.8 Smaller studies have also demonstrated increased risk for earlier conduit failure for conduits placed at younger ages9 and for patients with preexisting branch pulmonary artery stenosis.10
With the increasing availability and utility of genetic testing, it is possible that patients may also have genetic predisposition for early conduit failure. This study sought to analyze current RV-PAC longevity and to determine genetic risk factors associated with conduit longevity. We hypothesized that children with genetic syndromes, specifically 22q11 deletion syndrome, might have accelerated RV-PAC failure.
Methods
We conducted a retrospective cohort study by querying the Children's Hospital of Philadelphia's institutional surgical database for patients who underwent initial RV-PAC placement as part of a biventricular repair at 0 to 24 months of age between January 2010 and June 2020. Patients who underwent single-ventricle palliation and those who underwent RVPAC placement without concomitant ventricular septal defect closure were excluded from the study. The study was approved by the institutional review board (no. 21-018647, approved June 11, 2021). Data were obtained using the institution's EPIC electronic medical record. All data were collected and stored via an online survey created on the REDCap software platform. Because of the retrospective nature of the study, patient consent was not required.
The primary end point, hereto referred to as “conduit failure,” was defined as time to either surgical RV-PA conduit replacement, surgical pulmonary valve replacement, or transcatheter pulmonary valve replacement. Patients who did not undergo conduit replacement during the study period were censored at either their most recent follow-up appointment or date of death. The main exposure of interest was the presence of 22q11.2 deletion syndrome on genetic evaluation and testing. Other independent variables/covariates included demographic characteristics, birth history, surgical and cardiac catheterization history (including number of RV-PAC catheter interventions), and clinical follow-up.
Patients’ underlying cardiac diagnoses were classified by their primary anatomic lesion. Conduit valve sizes were normalized to pulmonary valve annulus z scores, which were calculated using the Pediatric Heart Network z-score regression model.11 Body surface area was calculated using the Haycock equation. Conduit position was defined as either orthotopic, referring to a conduit with anastomoses at the native right ventricular outflow tract and pulmonary artery bifurcation, or heterotopic, which included all other conduit positions.12
Genetic diagnoses were classified on the basis of clinical evaluation by genetics experts and genetic testing results. For the purposes of this study, patients with variants of unknown significance (VUS) were not considered to have genetic abnormalities and were included in the group with no evidence of a genetic syndrome. None of the VUS have been reclassified in the interim as either normal variants or associations with genetic syndromes.
Statistical Analysis
Patients’ demographic and clinical characteristics data were summarized and are reported as median and interquartile ranges for continuous variables with skewed distributions, mean with standard deviation for continuous variables with normal distributions, and counts and percentages are provided for categorical variables.
To assess the factors associated with freedom from conduit failure, a cumulative incidence curve and the Gray test were first used. These curves also provided a visual assessment of the proportional hazard assumption and to see where violations occurred. Univariate cause-specific Cox regression analyses were then performed to assess the association between each exposure and time to conduit failure. Variables significant at a level of .05 in univariate analysis were considered for inclusion in the final multivariate cause-specific Cox regression model. Potential violations of the proportional hazard assumption were assessed by testing a time-interaction term in the model and the score process test. Variance inflation factor was used to identify the multicollinearity among these factors.
We divided the cohort's conduit sizes into 3 groups: small (<1), medium (1-2), and large (>2) conduits. With evidence of similar survival functions between the medium conduit size group and the large conduit size group from the cumulative incidence curves and conduit size's violation of proportional hazard assumption, the final multivariable cause-specific Cox regression model was conducted comparing the small size conduit and medium/large conduit for the first 24 months and after 24 months separately.
The cause-specific Cox regression models did not include the 12 patients with orthotopic conduit placement because none of these patients underwent conduit replacement during the study's follow-up period. Furthermore, since only 1 patient underwent conduit placement with a Contegra valve, they were similarly excluded from the cause-specific Cox regression. To further analyze the possible impact of diagnosis of 22q11.2 deletion syndrome on conduit longevity, a subgroup was analyzed including the conotruncal lesions associated with it, namely the diagnoses of TOF, truncus arteriosus, or interrupted aortic arch.
Results
A total of 143 patients met inclusion criteria. Of the cohort, 59% were female, with a mean birth weight of 2.8 ± 0.7 kg and a mean birth height of 47.3 ± 4.0 cm. The average age of initial conduit placement was 4.3 ± 5.0 months. Of the cohort, 65 of the 143 children (45.5%) had their conduits replaced within the study period, with a median time to failure of 89 months (7.4 years) (Table 1). The estimated incidence of conduit failure at 1, 2, 3, and 5 years was 10%, 21%, 27%, and 37%, respectively (Figure 1). Sex was not found to be significantly associated with a shorter time to failure.
Table 1.
Clinical characteristics of patients undergoing RV-PAC placement (N = 143)
| Characteristic | n (%) or median (IQR) |
|---|---|
| Sex | |
| Male | 59 (41%) |
| Female | 84 (59%) |
| Age at conduit placement, mo | 3.1 (0.1-6.7) |
| Neonatal conduit placement (<1 mo) | 65 (45%) |
| Gestational age at birth | |
| Preterm (<37 wk) | 38 (27%) |
| Term (>37 wk) | 105 (73%) |
| Birth weight, kg | 2.8 (2.4-3.4) |
| Birth height, cm | 48 (46-50) |
| Anatomic diagnosis | |
| Tetralogy of Fallot (TOF) | 52 (36%) |
| TOF only | 6 (4%) |
| TOF + pulmonary atresia | 38 (27%) |
| TOF other | 8 (5%) |
| Truncus arteriosus | 38 (27%) |
| Double outlet right ventricle | 4 (3%) |
| Transposition of the great arteries (TGA) | 14 (10%) |
| TGA only | 0 |
| TGA + pulmonic stenosis | 10 (7%) |
| TGA other | 4 (3%) |
| Aortic atresia/ventricular septal defect | 6 (4%) |
| Pulmonary atresia | 12 (8%) |
| Aortic stenosis/aortic insufficiency | 13 (9%) |
| Interrupted aortic arch | 4 (3%) |
| Number of catheter interventions before end point | |
| 0 | 77 (54%) |
| 1 | 35 (24%) |
| 2 or more | 31 (22%) |
| Absolute size of conduit, mm | 13 (10, 15) |
| Size of conduit (z score of pulmonary annulus) | 1.4 (0.5-2.3) |
| Size of conduit category (z score of pulmonary annulus) | |
| <1 (small) | 54 (38%) |
| 1-2 (medium) | 41 (29%) |
| >2 (large) | 48 (34%) |
| <1 (small) | 2.5 (0.1, 6.4) |
| Age at size of conduit category, mo | |
| 1-2 (medium) | 0.6 (0.1, 6.1) |
| >2 (large) | 5.1 (0.2, 8.0) |
| Conduit material | |
| Aortic homograft | 112 (78%) |
| Pulmonary homograft | 30 (21%) |
| Bovine jugular vein valved conduit (Contegra) | 1 (1%) |
| Conduit position | |
| Heterotopic | 131 (92%) |
| Orthotopic | 12 (8%) |
| Prenatal testing | |
| Yes | 55 (38%) |
| No | 53 (37%) |
| Unsure/not documented | 35 (24%) |
| Postnatal testing | 101 (71%) |
| Confirmed genetic disorders | |
| 22q11.2 deletion syndrome (DiGeorge) | 27 (19%) |
| CHARGE syndrome | 2 (1%) |
| Neurofibromatosis type 1 | 2 (1%) |
| Trisomy 21 | 1 (1%) |
| Other | 16 (11%) |
| Any genetic disorders | 41 (29%) |
RV-PAC, Right ventricle-to-pulmonary artery conduit; IQR, interquartile range.
Figure 1.
Cumulative incidence curve depicting time to conduit failure for all patients included int the study. Approximately one half of patients fail at 7.4 years after conduit placement.
Multivariable Cause-Specific Cox Regression Analysis
Multivariable regression analysis identified 2 variables significantly associated with the risk of conduit failure: type of homograft and conduit size. Aortic homografts were associated with greater risk of conduit failure. Small conduits were associated with earlier conduit failure only within the first 24 months after placement. After the initial 24 months, small conduits were not associated with a greater risk of conduit failure than other conduits (Figure 2). Younger age at conduit placement showed a trend towards being associated with earlier conduit failure but was ultimately not significant. The presence of 22q11.2 deletion syndrome was not associated with earlier conduit failure after controlling for other covariates (Figure 3, Table 2).
Figure 2.
Cumulative incidence curve depicting time to conduit failure depending on the presence of 22q11.2 deletion syndrome. Notably, there was no difference in the Gray test (P = .21), meaning 22q11.2 deletion syndrome had no significant impact on conduit longevity.
Figure 3.
Cumulative incidence curve depicting time to conduit failure depending on the size of conduit placed. Small conduits demonstrated the fastest time to failure, whereas medium and large conduits were relatively similar in their outcomes (P = .0001).
Table 2.
Multivariate cause-specific Cox regression analysis
| Characteristic | Comparison | Multivariate model |
|
|---|---|---|---|
| Adjusted HR (95% CI) | P value | ||
| 22q11.2 deletion syndrome | Yes vs no | 1.34 (0.71-2.53) | .37 |
| Age at conduit placement | − | 0.93 (0.87-1.00) | .053 |
| Size of conduit | |||
| First 24 mo | <1 vs ≥ 1 | 3.99 (1.69-9.41) | .002 |
| 24 mo or after | <1 vs ≥ 1 | 1.45 (0.73-2.88) | .29 |
| Conduit material | Pulmonary vs aortic homograft | 0.29 (0.11-0.77) | .01 |
Genetic Factors for Conduit Longevity
Of the 143 children, 38% had prenatal genetic testing, and the remainder had postnatal genetic evaluations. A total of 42 children (29%) were found to have a genetic disorder, of whom 27 had positive genetic testing for 22q11.2 deletion syndrome. This comprised the largest group of those with a genetic disorder. There were 7 patients with positive testing for VUS. Within the group of patients with abnormal genetic testing, there were no other single diagnoses with more than 2 patients (Table 1). Having any genetic disorder was found to be significantly associated with a shorter time to failure in univariable cause-specific Cox analyses (Table 3). A diagnosis of 22q11.2 deletion syndrome trended toward a shorter time to failure; however, it was not statistically significant. To explore whether conduit size may have confounded the trend towards earlier conduit failure in patients with 22q11.2 deletion syndrome, we performed a subgroup analysis comparing initial conduit z-score distributions between patients with and without 22q11.2 deletion syndrome. The proportion of patients receiving conduits with z scores <1, 1-2, and >2 did not differ between the 2 groups (Table E1).
Table 3.
Factors associated with freedom from conduit failure
| Characteristic | Comparison | Univariate cause-specific Cox model |
|
|---|---|---|---|
| HR (95% CI) | P value | ||
| Gender | Female vs male | 1.16 (0.71-1.89) | .55 |
| Underlying diagnosis | |||
| TOF | Yes vs no | 0.89 (0.53-1.50) | .66 |
| Truncus arteriosus | Yes vs no | 2.11 (1.27-3.53) | .004 |
| Truncus arteriosus (TA; age at conduit placement <1) | Yes vs no | 1.52 (0.77-3.01) | .22 |
| Pulmonary atresia (PA) | Yes vs no | 0.99 (0.60-1.65) | .98 |
| Underlying diagnosis group∗ | |||
| TOF + PA | Reference | − | − |
| Other TOF | Other TOF vs TOF + PA | 1.14 (0.44-2.93) | .79 |
| Other PA | Other PA vs TOF + PA | 1.41 (0.60-3.33) | .44 |
| TA | TA vs TOF + PA | 1.92 (1.00-3.69) | .05 |
| Other | Other vs TOF + PA | 0.64 (0.30,1.34) | .24 |
| Genetic disorders | |||
| 22q11.2 deletion syndrome (DiGeorge) | Yes vs no | 1.80 (0.96-3.36) | .07 |
| Any genetic disorders | Yes vs no | 1.82 (1.06-3.11) | .03 |
| Age at conduit placement | − | 0.91 (0.85-0.97) | .003 |
| Size of conduit (z score) | |||
| − | 0.69 (0.56-0.84) | <.001 | |
| <1 vs >2 | 2.87 (1.60, 5.15) | .0004 | |
| 1-2 vs >2 | 1.22 (0.59, 2.54) | .59 | |
| Conduit material† | |||
| Aortic homograft vs pulmonary homograft | 5.00 (1.89, 12.50) | .001 | |
| Conduit position‡ | |||
| Orthotopic vs heterotopic | − | − | |
| Number of catheter interventions prior to endpoint | |||
| 1 or more vs 0 | 1.13 (0.69, 1.85) | .63 | |
HR, Hazard ratio; CI, confidence interval; TOF, tetralogy of Fallot.
TOF_PA 38 (27%), other TOF 14 (10%), other PA 12 (8%), TA 38 (27%), other 41 (29%).
The 1 patient with bovine jugular vein valved conduit (Contegra) was excluded from the analysis.
The 12 patients with orthotopic conduit positions had no failure. The Cox regression cannot be used to assess the effect of conduit position.
Subanalysis of the Group With TOF, Truncus Arteriosus, and Interrupted Aortic Arch
To further analyze the possible impact of the 22q11.2 deletion syndrome on conduit longevity, a subgroup of patients with the diagnoses of TOF, truncus arteriosus, or interrupted arch was formed (N = 96). All patients with 22q11.2 deletion syndrome within the study cohort had one of these primary diagnoses. Within this subgroup, 22q11.2 deletion syndrome was not associated with a shorter time to failure in any of the analyses.
Diagnostic Factors for Conduit Longevity
The major diagnoses necessitating repair with an RV-PAC were TOF with severe pulmonary stenosis, TOF with pulmonary atresia, and truncus arteriosus (Table 1). In univariable Cox analyses, truncus arteriosus was significantly associated with a shorter time to conduit failure. However, all but 1 patient with truncus arteriosus were younger than 1 year old at the time of conduit placement. Within this subgroup of patients younger than 1 year of age, truncus arteriosus was not associated with time to failure (Figure E1). The apparent effect of truncus arteriosus on conduit failure was confounded by age at placement and was therefore not included in the final multivariable Cox regression model (Table 3).
Figure E1.
Cumulative incidence curve depicting time to conduit failure depending on the presence of a diagnosis of truncus arteriosus. The Gray test demonstrated a significant difference in time to failure (P = .002).
Surgical Factors for Conduit Longevity: Conduit Size, Type, and Interim Conduit Interventions
Younger age at initial conduit placement was associated with a shorter time to failure in the univariable cause-specific Cox analysis (Table 3); however, it did not remain significant in the adjusted multivariable model (Table 2). The cumulative incidence function analysis (Figure 2) and the multivariable cause-specific Cox regression analysis revealed increased hazard of conduit failure in the subjects with conduit size z score less than 1 when compared with subjects with conduit sizes greater than or equal to 1 in the first 24 months; however this effect did not persist after the initial 24 months after placement.
Aortic homografts were inferior to pulmonary homografts in terms of conduit longevity (Table 3 and Figure 4). An interaction term between 22q11.2 deletion syndrome and conduit material added to the multivariable Cox regression model was not significant, indicating no difference in effect from the genetic abnormality on outcomes according to type of homograft.
Figure 4.
Cumulative incidence curve depicting time to conduit failure depending on the type of homograft used. Pulmonary homografts were superior to aortic homografts (P = .0002).
Lastly, neither 1 nor 2+ catheter interventions prior to failure were associated with increased longevity compared with those who underwent no catheterization interventions (Table 3, Figure E2).
Figure E2.
Cumulative incidence curve depicting the time to conduit failure depending on whether or not the patient underwent a catheter interventions. The Gray test did not demonstrate a statistically significant time to failure.
Discussion
This study analyzed the effects of surgical, diagnostic, and genetic factors on RV-PAC longevity in children with congenital heart disease. To our knowledge, it is the first to investigate the association of genetic syndromes with conduit longevity. We identified several factors associated with reduced conduit longevity in univariable analyses, including diagnosis of truncus arteriosus, presence of any genetic disorder, smaller conduit size, use of aortic homograft, and earlier conduit placement. On multivariable analysis, only pulmonary homografts and larger conduits had a longevity benefit in the first 24 months after surgery, independently of age at conduit replacement and diagnosis of 22q11.2 deletion syndrome.
There was no significant association between the presence of genetic syndromes and earlier conduit failure. The group of 41 patients in this cohort that had abnormal genetic testing comprised a wide range of genetic disorders, of which 22q11.2 deletion made up the majority. These patients are often born with hypocalcemia due to abnormal parathyroid hormone regulation, which may in turn lead to differences in calcium regulation and a propensity for calcifications—a known risk factor for early conduit degeneration.13 As a result, we had hypothesized that this syndrome would be associated with earlier time to conduit failure, however, we did not find this to be true in our analysis.
The fact that a diagnosis of truncus arteriosus was significant on univariate but not multivariate analysis suggests that surgical factors such as conduit size, type, and timing may be determinants of failure, rather than diagnosis alone. Furthermore, the unique anatomical features of truncus arteriosus, including markedly dilated or dysplastic pulmonary artery and branches, may further complicate this surgical decision-making. However, given our findings, it is likely that much of what drives earlier conduit failure in patients with truncus arteriosus is the need for conduit placement in the neonatal period (Table E2).
Previous studies have focused on conduit material and size as factors affecting longevity. It has been long believed that conduit oversizing is ideal to increase longevity in the context of somatic outgrowth, and several studies have supported this finding.2,3,6,8,9 However, more recently, Askovich and colleagues4 found that oversizing may be disadvantageous and lead to a shorter time to failure. They used a z score of +2.7 as the cut-off for oversizing: the mean conduit z score in our study was +1.6, indicating that our center does not favor conduit oversizing. Importantly, the association between smaller conduit size and earlier failure was limited to the first 24 months postimplantation in our study. This time-dependent effect is likely reflective of rapid somatic growth that occurs during early childhood, which is why smaller conduits have been associated with earlier conduit failure. However, as this rate of growth slows, the relative mismatch between conduit size and the patient's anatomy likely stabilizes, diminishing the impact of size on conduit longevity.
Similar to our findings, most studies have found pulmonary homografts to be superior to aortic homografts.2,4,6,8,9 This can present a challenge in younger patients, because aortic homografts are more readily available in smaller sizes, which may explain the skewed distribution of aortic homografts in this study population. The use of xenografts, such as the bovine jugular venous valved conduit (Contegra), needs further investigation. There was only one patient in this study that underwent conduit placement with a Contegra valve, and this patient was removed from the analysis.
Although univariate analyses demonstrated that patients with diagnoses of truncus arteriosus or TOF with pulmonary atresia necessitating RV-PAC were at greater risk of conduit failure than patients with other diagnoses, these findings did not remain significant on multivariable analyses. Much of what drives earlier conduit failure in patients with truncus arteriosus is the need for conduit placement in the neonatal period, rather than a specific anatomical issue associated with the diagnosis. Although previous studies have found an association between diagnosis of truncus arteriosus and earlier conduit failure, they similarly lacked the specific anatomical data necessary to conclude what may drive this association.6
Surprisingly, interim catheterizations were not associated with increased conduit longevity. This is contrary to previous studies, which have found not only increased conduit life span, but also immediate improvement in hemodynamic parameters.14 There are several potential explanations for this discrepancy. The effectiveness of catheter interventions may depend on the type of pathology or the specific nature of the conduit dysfunction. Furthermore, differences in study population, procedural techniques, and institutional practices across studies may contribute to these contrasting results. This discrepancy highlights the need for future studies focused on delineating the factors that influence the long-term effectiveness of catheter-based interventions, including patient characteristics, conduit type, and timing.
This single-center, retrospective cohort study was limited by small sample size, particularly when evaluating the impact of genetic syndromes on conduit failure. Importantly, only 29% of this cohort had a genetic disorder, with little variability in diagnoses. This is because 22q11 is the overwhelming genetic diagnosis in patients who have conduits. As a result, this study is not sufficiently powered to detect small-to-moderate effects of a diverse set of genetic syndromes. To accurately assess all genetic risk factors for RV-PAC failure, a multi-institutional approach with comprehensive genetic testing would be necessary. In addition, we chose to focus on initial conduit placements in neonates, infants, and small children, given the greater rates of conduit failure in these patients. Further data collection and analysis could focus on the longevity of subsequent conduits. Furthermore, the Gray test demonstrated improved overall conduit longevity for those placed in the orthotopic position (eg, Ross procedure), but these patients had to be excluded from the cause-specific Cox regression analysis because none of these conduits were replaced during the study period. Therefore, we cannot make any further conclusions about the impact of use of Contegra valves or orthotopic positioning on conduit failure. We were unable to reliably determine the primary indication for conduit replacement, as operative notes and clinical documentation often lacked sufficient detail. As a result, we could not differentiate between replacements performed due to conduit dysfunction versus those done for other reasons. Lastly, we did not include other forms of transcatheter interventions such as balloon dilation or stent placement in the definition of failure, which may have led to the study underestimating the true burden of conduit dysfunction.
Conclusions
Early RV-PAC failure remains related to initial conduit size and conduit material. Genetic syndromes, including 22q11.2 deletion, were not associated with earlier time to conduit failure. When planning surgical repair, conduit size and type should be the most important factors considered in estimating conduit longevity. With a larger sample size that allows for further advanced regression and subgroup analysis, we may be able to provide a more concrete estimate of an individual's average time to conduit failure on the basis of their individual factors.
Conflict of Interest Statement
The authors reported no conflicts of interest.
The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest.
Contributor Information
Laura Mercer-Rosa, Email: mercerrosal@chop.edu.
Meryl S. Cohen, Email: cohenm@chop.edu.
Appendix E1
Table E1.
Size of conduit by the 22q11.2 deletion status
| Size of conduit (z score) | 22q11.2 |
P value | |
|---|---|---|---|
| Yes (n = 27) | No (n = 116) | ||
| <1 | 12 (44%) | 42 (36%) | .06 |
| 1-2 | 11 (41%) | 30 (26%) | |
| >2 | 4 (15%) | 44 (38%) | |
Table E2.
Relationship between truncus arteriosus (TA) and age at conduit placement
| Age at conduit placement, mo | Presence of a diagnosis of TA |
P value | |
|---|---|---|---|
| Yes | No | ||
| <1 | 37 (97%) | 28 (27%) | <.001 |
| 1-8 | 1 (3%) | 51 (49%) | |
| ≥8 | 0 | 26 (25%) | |
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