Outcomes after pediatric pulmonary valve replacement in patients with tetralogy of Fallot.

BACKGROUND: People with tetralogy of Fallot (TOF) may require a transannular patch during primary repair, which leads to pulmonary valve regurgitation. Pulmonary valve replacement (PVR) is performed to prevent complication of chronic pulmonary regurgitation, but the optimal timing of PVR remains a matter of debate. This study aimed at assessing the association of PVRs performed <18 years of age on the rate of hospitalizations, interventions, and mortality. METHODS: This is a retrospective observational cohort of people with TOF born in Québec between 1982 and 2015, combining clinical and administrative data. Marginal means/rates models and survival curves were used to compare outcomes between patients with pediatric PVR (<18 years) and those without. Outcomes of interest were rates of cardiac hospitalizations, all-cause hospitalizations, cardiac interventions, and mortality. Groups were balanced using models weighed on the inverse probability of receiving pediatric PVR. RESULTS: Of the 316 eligible patients, 58 (18.4%) received a pediatric PVR. Compared to patients not receiving pediatric PVR, they were at increased risk of cardiac hospitalizations, although the rates of cardiac hospitalization were low: 0.50 versus 0.09 hospitalizations per 20 years [Hazard ratio (HR)=4.71 (95%CI 2.22-9.96)]. Patients receiving a pediatric PVR had a comparable risk of all-cause hospitalizations [HR=0.95 (95%CI 0.71-1.26)] and of cardiac interventions [HR=1.13 (95%CI 0.72-1.77)]. CONCLUSIONS: Patients who underwent pediatric PVR had higher rates of cardiac hospitalizations, but similar rates of all-cause hospitalizations, cardiac procedures, and mortality. In this observational cohort, pediatric PVR was not associated with an improved outcome.

The Quebec Congenital Heart Disease Registry: A Model of Prospective Databank to Facilitate Research in Congenital Cardiology.

Background: A national registry of congenital heart disease (CHD) would facilitate project initiation, decrease costs, increase statistical power, and avoid duplication. Establishing such registries poses numerous challenges, but the current Canadian research ecosystem in CHD is well positioned to meet them. We assessed the feasibility of building a province-wide CHD registry by automatically identifying people with CHD and extracting their native cardiac anatomy from multiple clinical data sources, without the need for manual data entry. Methods: We designed a CHD registry of all fetuses and children with at least 1 echocardiographic report confirming CHD since 2000. We interfaced the registry with several clinical and echocardiography data sources from all paediatric cardiology programmes in Québec. Results: We extracted 885,287 echocardiogram reports and 70,121 clinical records. We identified CHD in 43,452 children and 4682 fetuses. There were 1128 (2.3%) cases with files in multiple institutions, and patients with more complex CHD were 3 times more likely to be seen in more than 1 institution. So far, the registry has been used to build and link CHD cohorts for 7 distinct projects. Conclusions: We demonstrated the feasibility of a baseline CHD registry in Québec without the need for manual data entry, in which other CHD research projects could be nested. This could serve as a blueprint to expand the registry and to develop an integrated approach where data gathered in caring for patients with CHD serve as data layers that incrementally contribute to a national cohort, for which data remain easily accessible and usable.

Contexte: Un registre national des cardiopathies congénitales (CC) pourrait faciliter le lancement de projets de recherche, en diminuer les coûts, en améliorer la puissance statistique tout en évitant les redondances. La mise en place de tels registres pose de nombreux défis, mais l'écosystème de recherche canadien dans le domaine de la CC est bien placé pour y répondre. Nous avons évalué la faisabilité de la mise en place d'un registre des CC à l'échelle provinciale par l'identification automatique des personnes atteintes de CC et l'extraction de leur anatomie cardiaque native à partir de plusieurs sources de données cliniques, sans nécessiter de saisie manuelle de données. Méthodologie: Nous avons conçu un registre des CC incluant tous les fœtus et les enfants pour qui au moins un rapport d'évaluation électrocardiographique confirmait la présence d'une CC depuis 2000. Le registre a été mis en relation avec plusieurs sources de données cliniques et échocardiographiques provenant de tous les programmes en cardiologie pédiatrique au Québec. Résultats: Nous avons extrait 885 287 rapports d'échocardiographie et 70 121 dossiers cliniques. La présence d'une CC a été établie chez 43 452 enfants et 4 682 fœtus. Dans 1 128 cas (2,3 %), un dossier existait dans plus d'un établissement. Les patients présentant des CC plus complexes étaient 3 fois plus susceptibles d'être suivis dans plus d'un établissement. Jusqu'à présent, le registre a été utilisé pour établir et mettre en relation des cohortes de patients atteints de CC pour sept projets de recherche distincts. Conclusions: Nous avons démontré la faisabilité de la mise en place d'un registre de référence des CC au Québec sans recours à la saisie manuelle de données, dans lequel peuvent se nicher d'autres projets de recherche sur les CC. Notre démarche pourrait servir de prototype pour une expansion du registre et pour une approche d'intégration des données recueillies dans la prestation de soins aux patients atteints de CC, afin de former des couches de données qui s'ajoutent au fur et à mesure à une cohorte nationale, avec des données faciles à obtenir et à utiliser.

Determinants and Clinical Outcomes of Patients With Tetralogy of Fallot Lost to Cardiology Follow-up.

BACKGROUND: Various rates of loss to follow-up (LTFU) have been reported in patients with congenital heart disease, but return to follow-up is rarely considered in those analyses. Outcomes of LTFU patients are difficult to assess because the patients no longer attend cardiac care. We leveraged data from the TRIVIA cohort, which combines more than 30 years of clinical and administrative data, allowing us to study outcomes even after LTFU. METHODS: This population-based cohort included 904 patients with tetralogy of Fallot (TOF) born from 1982 to 2015 in Québec, Canada. Risk factors for LTFU and outcomes were calculated by Cox models and marginal means/rates models. Outcomes of LTFU patients were compared with propensity score-matched non-LTFU patients. RESULTS: The cumulative risk of experiencing 1 episode of LTFU was 50.3% at 30 years. However, return to follow-up was frequent and the proportion of patients actively followed was 85.9% at 10 years, 76.4% at 20 years, and 70.6% at 30 years. Factors associated with a reduced risk of LTFU were primary repair with conduit (hazard ratio [HR] 0.29, 95% confidence interval [CI] 0.15-0.58) and transannular patch (HR 0.60, 95% CI 0.46-0.79). LTFU patients had lower rates of cardiac hospitalisations (HR 0.49, 95% CI 0.42-0.56) and cardiac interventions (HR 0.32, 95% CI 0.25-0.42), but similar rates of cardiac mortality (HR 0.95, 95% CI 0.24-3.80). CONCLUSIONS: There was a lower proportion of LTFU patients compared with previous studies. Factors associated with lower rates of LTFU were conduits and non-valve-sparing surgery. LTFU patients had lower rates of cardiac procedures and cardiac hospitalisations.

Incremental Detection of Severe Congenital Heart Disease by Fetal Echocardiography Following a Normal Second Trimester Ultrasound Scan in Québec, Canada.

BACKGROUND: The benefit of fetal echocardiograms (FE) to detect severe congenital heart diseases (SCHD) in the setting of a normal second-trimester ultrasound is unclear. We aimed to assess whether the increase in SCHD detection rates when FE are performed for risk factors in the setting of a normal ultrasound was clinically significant to justify the resources needed. METHODS: This is a multicenter, population-based, retrospective cohort study, including all singleton pregnancies and offspring in Quebec (Canada) between 2007 and 2015. Administrative health care data were linked with FE clinical data to gather information on prenatal diagnosis of CHD, indications for FE, outcomes of pregnancy and offspring, postnatal diagnosis of CHD, cardiac interventions, and causes of death. The difference between the sensitivity to detect SCHD with and without FE for risk factors was calculated using generalized estimating equations with a noninferiority margin of 5 percentage points. RESULTS: A total of 688 247 singleton pregnancies were included, of which 30 263 had at least one FE. There were 1564 SCHD, including 1071 that were detected prenatally (68.5%). There were 12 210 FE performed for risk factors in the setting of a normal second-trimester ultrasound, which led to the detection of 49 additional cases of SCHD over 8 years. FE referrals for risk factors increased sensitivity by 3.1 percentage points (95% CI, 2.3-4.0; P<0.0001 for noninferiority). CONCLUSIONS: In the setting of a normal second-trimester ultrasound, adding a FE for risk factors offered low incremental value to the detection rate of SCHD in singleton pregnancies. The current ratio of clinical gains versus the FE resources needed to screen for SCHD in singleton pregnancies with isolated risk factors does not seem favorable. Further studies should evaluate whether these resources could be better allocated to increase SCHD sensitivity at the ultrasound level, and to help decrease heterogeneity between regions, institutions and operators.