Exercise Performance and 22q11.2 Deletion Status Affect Quality of Life in Tetralogy of Fallot

Clinically Relevant Genetic Considerations for Patients With Tetralogy of Fallot

Genetic changes affect embryogenesis, cardiac and extracardiac phenotype, development, later onset conditions, and both short- and long-term outcomes and comorbidities in the increasing population of individuals with tetralogy of Fallot (TOF). In this review, we focus on current knowledge about clinically relevant genetics for patients with TOF across the lifespan. The latest findings for TOF genetics that are pertinent to day-to-day practice and lifelong management are highlighted: morbidity/mortality, cardiac/extracardiac features, including neurodevelopmental expression, and recent changes to prenatal screening and diagnostics. Genome-wide microarray is the first-line clinical genetic test for TOF across the lifespan, detecting relevant structural changes including the most common for TOF, the 22q11.2 microdeletion. Accumulating evidence illustrates opportunities for advances in understanding and care that may arise from genetic diagnosis at any age. We also glimpse into the near future when the multigenic nature of TOF will be more fully revealed, further enhancing possibilities for preventive care. Precision medicine is nigh.

Comparison of treatment strategies for neonates with tetralogy of Fallot and pulmonary atresia

OBJECTIVE

Neonates with tetralogy of Fallot and pulmonary atresia (TOF/PA) but no major aorta-pulmonary collaterals are dependent on the arterial duct for pulmonary blood flow and require early intervention, either by primary (PR) or staged repair (SR) with initial palliation (IP) followed by complete repair (CR). The optimal approach has not been established.

METHODS

Neonates with TOF/PA who underwent PR or SR were retrospectively reviewed from the Congenital Cardiac Research Collaborative. Outcomes were compared between PR and SR (IP + CR) strategies. Propensity scoring was used to adjust for baseline differences. The primary outcome was mortality. Secondary outcomes included complications, length of stay, cardiopulmonary bypass and anesthesia times, reintervention (RI), and pulmonary artery (PA) growth.

RESULTS

Of 282 neonates, 106 underwent PR and 176 underwent SR (IP: 144 surgical, 32 transcatheter). Patients who underwent SR were more likely to have DiGeorge syndrome and greater rates of mechanical ventilation before the initial intervention. Mortality was not significantly different. Duration of mechanical ventilation, inotrope use, and complication rates were similar. Cumulative length of stay, cardiopulmonary bypass, and anesthesia times favored PR (P ≤ .001). Early RI was more common in patients who underwent SR (rate ratio, 1.42; P = .003) but was similar after CR (P = .837). Conduit size at the time of CR was larger with SR. Right PA growth was greater with PR.

CONCLUSIONS

In neonates with TOF/PA, SR is more common in greater-risk patients. Accounting for this, SR and PR strategies have similar mortality. Perioperative morbidities, RI, and right PA growth generally favor PR, whereas SR allows for larger initial conduit implantation.

Patient-Reported Outcomes After Tetralogy of Fallot Repair

BACKGROUND

Comprehensive assessment of tetralogy of Fallot (TOF) outcomes extends beyond morbidity and mortality to incorporate patient-reported outcomes (PROs), including quality of life (QOL) and health status (HS).

OBJECTIVES

This study explored PROs in adolescents and adults with TOF and delineated variables associated with PROs.

METHODS

This was a cross-sectional observational study within a larger prospective registry of adolescents and adults with repaired TOF and moderate or greater pulmonary regurgitation from North America, Europe, and Asia. Participants completed PROs, including a QOL linear analogue scale (QOL-LAS) and an HS visual analogue scale (HS-VAS). Scores were classified according to age cohorts: <18, 18 to 25, 26 to 40, and >40 years.

RESULTS

The study included 607 patients (46.3% female; median age 28.5 years). Median QOL-LAS scores (0-100) were similar across age cohorts (85, 80, 80, 80; P = 0.056). Median HS-VAS scores (0-100) were lowest for the oldest cohort (77) compared with the 3 younger cohorts (85, 80, 80) (P = 0.004). With advancing age, there were increased reports of poor mobility (P < 0.001) and pain or discomfort (P = 0.004); problems in these dimensions were reported by 19.1% and 37.2% of patients aged >40 years, respectively. Of factors associated with superior PROs on multivariable regression modeling (ie, being White, being nonsyndromic, having employment, and having better left ventricular function; P < 0.05), asymptomatic status (functional class I) was the variable associated with the greatest number of QOL and HS measures (P < 0.001).

CONCLUSIONS

Strategies to improve TOF outcomes should consider PROs alongside conventional clinical variables. Factors associated with poorer PROs represent opportunities to intervene to improve the lives of patients with TOF.

Fontan Geometry and Hemodynamics Are Associated With Quality of Life in Adolescents and Young Adults

BACKGROUND

Despite favorable short-term outcomes, Fontan palliation is associated with comorbidities and diminished quality of life (QOL) in the years after completion. We hypothesized that poor Fontan hemodynamics and ventricular function are associated with worse QOL.

METHODS

This was a single-center study of Fontan survivors aged more than 12 years. Subjects completed a cardiac magnetic resonance scan and QOL questionnaire. Cardiac magnetic resonance-derived variables included Fontan geometry, and hemodynamics. Computational fluid dynamics simulations quantified power loss, pressure drop, and total cavopulmonary connection resistance across the Fontan. Quality of life was assessed by completion of the Pediatric Quality of Life Inventory. Longitudinal and cross-sectional comparisons were made between cardiac magnetic resonance and computational fluid dynamics parameters with patient-reported QOL.

RESULTS

We studied 77 Fontan patients, median age 19.7 years (interquartile range, 17.1 to 23.6), median time from Fontan completion 16 years (interquartile range, 13 to 20). Longitudinal data were available for 48 patients; median time between cardiac magnetic resonance and QOL was 8.1 years (interquartile range, 7 to 9.4). Median patient-reported Pediatric Quality of Life Inventory total score was 80 (interquartile range, 67.4 to 88). Greater power loss and smaller left pulmonary artery diameter at baseline were associated with worse QOL at follow-up. Greater pressure drop was associated with worse QOL at the same time point.

CONCLUSIONS

For Fontan survivors, measures of computational fluid dynamics hemodynamics and geometry are associated with worse QOL. Interventional strategies targeted at optimizing the Fontan may improve QOL.

Comparative Costs of Management Strategies for Neonates With Symptomatic Tetralogy of Fallot

BACKGROUND

Recent data have demonstrated that overall mortality and adverse events are not significantly different for primary repair (PR) and staged repair (SR) approaches to management of neonates with symptomatic tetralogy of Fallot (sTOF). Cost data can be used to compare the relative value (cost for similar outcomes) of these approaches and are a potentially more sensitive measure of morbidity.

OBJECTIVES

This study sought to compare the economic costs associated with PR and SR in neonates with sTOF.

METHODS

Data from a multicenter retrospective cohort study of neonates with sTOF were merged with administrative data to compare total costs and cost per day alive over the first 18 months of life in a propensity score-adjusted analysis. A secondary analysis evaluated differences in department-level costs.

RESULTS

In total, 324 subjects from 6 centers from January 2011 to November 2017 were studied (40% PR). The 18-month cumulative mortality (P = 0.18), procedural complications (P = 0.10), hospital complications (P = 0.94), and reinterventions (P = 0.22) did not differ between PR and SR. Total 18-month costs for PR (median $179,494 [IQR: $121,760-$310,721]) were less than for SR (median: $222,799 [IQR: $167,581-$327,113]) (P < 0.001). Cost per day alive (P = 0.005) and department-level costs were also all lower for PR. In propensity score-adjusted analyses, PR was associated with lower total cost (cost ratio: 0.73; P < 0.001) and lower department-level costs.

CONCLUSIONS

In this multicenter study of neonates with sTOF, PR was associated with lower costs. Given similar overall mortality between treatment strategies, this finding suggests that PR provides superior value.

Resource Utilization in the First 2 Years Following Operative Correction for Tetralogy of Fallot: Study Using Data From the Optum's De-Identified Clinformatics Data Mart Insurance Claims Database

Background

Despite excellent operative survival, correction of tetralogy of Fallot frequently is accompanied by residual lesions that may affect health beyond the incident hospitalization. Measuring resource utilization, specifically cost and length of stay, provides an integrated measure of morbidity not appreciable in traditional outcomes.

Methods and Results

We conducted a retrospective cohort study, using de‐identified commercial insurance claims data, of 269 children who underwent operative correction of tetralogy of Fallot from January 2004 to September 2015 with ≥2 years of continuous follow‐up (1) to describe resource utilization for the incident hospitalization and subsequent 2 years, (2) to determine whether prolonged length of stay (>7 days) in the incident hospitalization was associated with increased subsequent resource utilization, and (3) to explore whether there was regional variation in resource utilization with both direct comparisons and multivariable models adjusting for known covariates. Subjects with prolonged incident hospitalization length of stay demonstrated greater resource utilization (total cost as well as counts of outpatient visits, hospitalizations, and catheterizations) after hospital discharge (P<0.0001 for each), though the number of subsequent operative and transcatheter interventions were not significantly different. Regional differences were observed in the cost of incident hospitalization as well as subsequent hospitalizations, outpatient visits, and the costs associated with each.

Conclusions

This study is the first to report short‐ and medium‐term resource utilization following tetralogy of Fallot operative correction. It also demonstrates that prolonged length of stay in the initial hospitalization is associated with increased subsequent resource utilization. This should motivate research to determine whether these differences are because of modifiable factors.

Determinants of Exercise Performance in Children and Adolescents with Repaired Tetralogy of Fallot Using Stress Echocardiography

Exercise performance is variable and often impaired in patients with repaired tetralogy of Fallot (rTOF). We sought to identify factors associated with exercise performance by comparing high to low performers on cardiopulmonary exercise testing (CPET) in patients with rTOF. We conducted a cross-sectional study of subjects presenting for CPET who underwent echocardiograms at rest and peak exercise. Patients with pacemakers and arrhythmias were excluded. Right ventricular (RV) global longitudinal strain was used as a measure of systolic function. Pulmonary insufficiency (PI) was assessed with the diastolic systolic ratio and the diastolic systolic time-velocity integral ratio by Doppler interrogation of the pulmonary artery. CPET measures included percent-predicted maximum [Formula: see text][Formula: see text], percent-predicted maximum work and oxygen pulse. High versus low performers were identified as those achieving [Formula: see text] of at least 80% or falling below, respectively. Differences in echocardiographic parameters from rest to peak exercise were examined using mixed-effects regression models. Compared to the low performers (n = 17), high performers (n = 12) were younger (12.8 ± 3.3 years vs. 18.3 ± 4.8 years), had normal chronotropic response (peak heart rate > 185 bpm) with greater heart rate reserve and superior physical working capacity. High performers also had a greater reduction in PI at peak exercise, despite greater PI severity at rest. Oxygen pulse was comparable between groups. For both groups, there was no association of PI severity and RV systolic function at rest with exercise parameters. There was no group difference in the magnitude of change in RV strain and diastolic parameters from rest to peak exercise. Chronotropic response to exercise appears to be an important parameter with which to assess exercise performance in rTOF. Chronotropic health should be taken into consideration in this population, particularly given that RV function and PI severity at rest were not associated with exercise performance.