Feeding Variation Among Infants in Acute Care Cardiology Units.

Infants with heart disease are at high risk of feeding difficulties and complications. Feeding practices amongst acute care cardiology units are not standardized. This study aims to describe feeding practices for infants at the time of discharge from a Pediatric Acute Care Cardiology Collaborative (PAC3) center and practice variation between centers. Discharge encounters for infants in the PAC3 registry between February 2019 and October 2021 were included. Nutrition type and feeding route at discharge were summarized with descriptive statistics and a modified bump plot. Center variation was assessed using funnel plots with control limits set at the 99.9% confidence interval from the group mean. A total of 15,414 encounters across 24 PAC3 centers were recorded from 8313 unique patients (median encounters 1, range 1-25). Nutrition at discharge consisted of standard formula in 8368 (54%), human milk in 6300 (41%), and elemental formula in 3230 (21%), either alone or in combination. Feeds were fortified to ≥ 24 kcal/oz in 12,359 (80%). Discharge supplemental tube feeding was present in 7353 (48%) encounters with 4643 (63%) receiving continuous feeds, 2144 (29%) bolus feeds, and 566 (8%) a combination. Funnel plots demonstrated variability in nutrition type and feeding route at discharge. Infants with heart disease commonly require high calorie nutrition and supplemental tube feedings at discharge. Feeding strategies at discharge vary widely between PAC3 centers. Collaborative approaches to identify best practices in feeding strategies are needed.

Immunisation deferral practices surrounding congenital heart surgery.

BACKGROUND: Perioperative immunisation administration surrounding congenital heart surgery is controversial. Delayed immunisation administration results in children being at risk of vaccine-preventable illnesses and is associated with failure to complete immunisation schedules. Among children with CHD, many of whom are medically fragile, vaccine-preventable illnesses can be devastating. Limited research shows perioperative immunisation may be safe and effective. METHODS: We surveyed Pediatric Acute Care Cardiology Collaborative member centres and explored perioperative immunisation practices. We analysed responses using descriptive statistics. RESULTS: Complete responses were submitted by 35/46 (76%) centres. Immunisations were deferred for any period prior to surgery by 23 (66%) centres and after surgery by 31 (89%) centres. Among those who deferred post-operative immunisation, 20 (65%) required deferral only for patients whose operations required cardiopulmonary bypass. Duration of deferral in the pre- and post-operative periods was variable. Many centres included exceptions to their policy for specific vaccine-preventable illnesses. Almost all (34, 97%) centres administer routine childhood immunisation to patients who remain admitted for prolonged periods. CONCLUSIONS: Most centres defer routine childhood immunisation for some period before and after congenital heart surgery. Centre specific practices vary. Immunisation deferral confers risk to patients and may not be warranted in this population. Further research would be necessary to understand the immunologic impact of these practices.

Caregiver and provider attitudes toward family-centred rounding in paediatric acute care cardiology.

Family-centered rounding has emerged as the gold standard for inpatient paediatrics rounds due to its association with improved family and staff satisfaction and reduction of harmful errors. Little is known about family-centered rounding in subspecialty paediatric settings, including paediatric acute care cardiology.In this qualitative, single centre study, we conducted semi-structured interviews with providers and caregivers eliciting their attitudes toward family-centered rounding. An a priori recruitment approach was used to optimise diversity in reflected opinions. A brief demographic survey was completed by participants. We completed thematic analysis of transcribed interviews using grounded theory.In total, 38 interviews representing the views of 48 individuals (11 providers, 37 caregivers) were completed. Three themes emerged: rounds as a moment of mutual accountability, caregivers' empathy for providers, and providers' objections to family-centered rounding. Providers' objections were further categorised into themes of assumptions about caregivers, caregiver choices during rounds, and risk for exacerbation of bias and inequity.Caregivers and providers in the paediatric acute care cardiology setting echoed some previously described attitudes toward family-centered rounding. Many of the challenges surrounding family-centered rounding might be addressed through access to training for caregivers and providers alike. Hospitals should invest in systems to facilitate family-centered rounding if they choose to implement this model of care as the current state risks erosion of provider-caregiver relationship.

Maternal Diabetes and Cardiovascular Health in the Offspring.

Pulse wave velocity (PWV) has been explored to predict cardiovascular health in adults. Less is known about neonatal PWV. We evaluated the association between arterial stiffness of neonates of mothers (NoM) with diabetes and childhood health. Neonatal brachial-femoral PWV (bfPWV) was measured after birth and neonates followed for a median of 5.2 years [1 month-6.6 years]. 36 pregnant women with pregestational diabetes mellitus PGDM (n = 12), gestational diabetes mellitus (GDM) (n = 13), and controls (n = 11) were enrolled. Neonates were similar in weight, gestational age, and delivery mode. 26 neonates had follow-up data including weight, height and blood pressure. More mothers with PGDM had poor glycemic control compared to mothers with GDM (83% vs. 8%; p = 0.0002). PWV was higher in NoM with PGDM than controls (3.4 ± 0.5 vs. 2.6 ± 0.8 m/s; p = 0.04). At follow-up, children of mothers with diabetes (n = 16) had higher weight percentile (78.5 ± 27.9 vs 49.5 ± 34.6%; p = 0.02) and diastolic blood pressure (DBP) (68 ± 13.6 vs 57.3 ± 4.3 mmHg; p = 0.01) than controls (n = 10). No correlation emerged between neonatal PWV and childhood body mass index (BMI) or maternal HbA1c. Results suggest maternal diabetes affect neonatal arterial stiffness and childhood blood pressure; however, the mechanism is unclear. The long-term implications of these findings warrant further investigation.

Direct Discharge to Home From the Pediatric Cardiovascular ICU.

OBJECTIVES: To describe direct discharge to home from the cardiovascular ICU. DESIGN: Mixed-methods including retrospective Pediatric Cardiac Critical Care Consortium and Pediatric Acute Care Cardiology Collaborative data and survey. SETTING: Tertiary pediatric heart center. PATIENTS: Patients less than 25 years old, with a cardiovascular ICU stay of greater than 24 hours and direct discharge to home from January 1, 2016, to December 8, 2020, were included. Select data describing patients discharged from acute care internally and nationally from Pediatric Acute Care Cardiology Collaborative sites were compared with the direct discharge to home cohort. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Encounter- and patient-specific characteristics. Seven-day and 30-day readmission and 30-day mortality served as surrogate safety markers. A survey of cardiovascular ICU frontline providers assessed comfort and skills related to direct discharge to home.There were 364 direct discharge to home encounters that met inclusion criteria. The majority of direct discharge to home encounters were associated with a surgery or procedure (305; 84%). There were 27 encounters (7.4%) for medical technology-dependent patients requiring direct discharge to home. Unplanned 7-day readmissions among direct discharge to home patients was 1.9% compared with 4.6% (p = 0.04) of patients discharged from acute care internally. Readmission among those discharged from acute care internally did not differ from those at Pediatric Acute Care Cardiology Collaborative sites nationally. Frontline cardiovascular ICU providers had mixed levels of confidence in technical aspects and low levels of confidence in logistics of direct discharge to home. CONCLUSIONS: Cardiovascular ICU direct discharge to home was not associated with increased unplanned readmissions compared with patients discharged from acute care and may be safe in select patients. Frontline cardiovascular ICU providers feel time constraints challenge direct discharge to home. Further research is needed to identify patient characteristics associated with safe direct discharge to home and systems needed to support this practice.Summary statistics are described using proportions or medians with interquartile ranges (IQRs) and were performed using Microsoft Excel (Microsoft, Redmond, WA). Two-sample tests of proportions were used to compare readmission frequency of the DDH cohort compared with internal and national PAC3 data using STATA Version 15 (StataCorp, College Station, TX).

Early Functional Status After Surgery for Congenital Heart Disease: A Single-Center Retrospective Study.

OBJECTIVES: The objective of this study is to investigate the change in functional status in infants, children, and adolescents undergoing congenital heart surgery using the Functional Status Scale. DESIGN: A single-center retrospective study. SETTING: A 26-bed cardiac ICU in a free-standing university-affiliated tertiary children's hospital. PATIENTS: All patients 0-18 years who underwent congenital heart surgery from January 1, 2014, to December 31, 2017. INTERVENTIONS: None. MEASUREMENTS AND MIN RESULTS: The primary outcome variable was change in Functional Status Scale scores from admission to discharge. Additionally, two binary outcomes were derived from the primary outcome: new morbidity (change in Functional Status Scale ≥ 3) and unfavorable functional outcome (change in Functional Status Scale ≥ 5); their association with risk factors was assessed using modified Poisson regression. Out of 1,398 eligible surgical encounters, 65 (4.6%) and 15 (1.0%) had evidence of new morbidity and unfavorable functional outcomes, respectively. Higher Surgeons Society of Thoracic and the European Association for Cardio-Thoracic Surgery score, single-ventricle physiology, and longer cardiopulmonary bypass time were associated with new morbidity. Longer hospital length of stay was associated with both new morbidity and unfavorable outcome. CONCLUSIONS: This study demonstrates the novel application of the Functional Status Scale on patients undergoing congenital heart surgery. New morbidity was noted in 4.6%, whereas unfavorable outcome in 1%. There was a small change in the total Functional Status Scale score that was largely attributed to changes in the feeding domain. Higher Society of Thoracic and the European Association for Cardio-Thoracic Surgery score, single-ventricle physiology, and longer cardiopulmonary bypass times were associated with new morbidity, whereas longer hospital length of stay was associated with both new morbidity and unfavorable outcome. Further studies with larger sample size will need to be done to confirm our findings and to better ascertain the utility of Functional Status Scale on this patient population.

Target-Based Care: An Intervention to Reduce Variation in Postoperative Length of Stay.

OBJECTIVES: To derive care targets and evaluate the impact of displaying them at the point of care on postoperative length of stay (LOS). STUDY DESIGN: A prospective cohort study using 2 years of historical controls within a freestanding, academic children's hospital. Patients undergoing benchmark cardiac surgery between May 4, 2014, and August 15, 2016 (preintervention) and September 6, 2016, to September 30, 2018 (postintervention) were included. The intervention consisted of displaying at the point of care targets for the timing of extubation, transfer from the intensive care unit (ICU), and hospital discharge. Family satisfaction, reintubation, and readmission rates were tracked. RESULTS: The postintervention cohort consisted of 219 consecutive patients. There was a reduction in variation for ICU (difference in SD -2.56, P < .01) and total LOS (difference in SD -2.84, P < .001). Patients stayed on average 0.97 fewer days (P < .001) in the ICU (median -1.01 [IQR -2.15, -0.39]), 0.7 fewer days (P < .001) on mechanical ventilation (median -0.54 [IQR -0.77, -0.50]), and 1.18 fewer days (P < .001) for the total LOS (median -2.25 [IQR -3.69, -0.15]). Log-transformed multivariable linear regression demonstrated the intervention to be associated with shorter ICU LOS (ß coefficient -0.19, SE 0.059, P < .001), total postoperative LOS (ß coefficient -0.12, SE 0.052, P = .02), and ventilator duration (ß coefficient -0.21, SE 0.048, P < .001). Balancing metrics did not differ after the intervention. CONCLUSIONS: Target-based care is a simple, novel intervention associated with reduced variation in LOS and absolute LOS across a diverse spectrum of complex cardiac surgeries.

High Acuity Therapy Variation Across Pediatric Acute Care Cardiology Units: Results from the Pediatric Acute Care Cardiology Collaborative Hospital Surveys.

We utilized the multicenter Pediatric Acute Care Cardiology Collaborative (PAC3) 2017 and 2019 surveys to describe practice variation in therapy availability and changes over a 2-year period. A high acuity therapies (ATs) score was derived (1 point per positive response) from 44 survey questions and scores were compared to center surgical volume. Of 31 centers that completed the 2017 survey, 26 also completed the 2019 survey. Scores ranged from 11 to 34 in 2017 and 11 to 35 in 2019. AT scores in 2019 were not statistically different from 2017 scores (29/44, IQR 27-32.5 vs. 29.5/44, IQR 27-31, p = 0.9). In 2019, more centers reported initiation of continuous positive airway pressure (CPAP) and Bi-level positive airway pressure (BiPAP) in Acute Care Cardiology Unit (ACCU) (19/26 vs. 4/26, p < 0.001) and permitting continuous CPAP/BiPAP (22/26 vs. 14/26, p = 0.034) compared to 2017. Scores in both survey years were significantly higher in the highest surgical volume group compared to the lowest, 33 ± 1.5 versus 25 ± 8.5, p = 0.046 and 32 ± 1.7 versus 23 ± 5.5, p = 0.009, respectively. Variation in therapy within the ACCUs participating in PAC3 presents an opportunity for shared learning across the collaborative. Experience with PAC3 was associated with increasing available respiratory therapies from 2017 to 2019. Whether AT scores impact the quality and outcomes of pediatric acute cardiac care will be the subject of further investigation using a comprehensive registry launched in early 2019.

The added value of the advanced practice provider in paediatric acute care cardiology.

OBJECTIVES: Advanced practice providers (APPs) are being employed at increasing rates in order to meet new in-hospital care demands. Utilising the Paediatric Acute Care Cardiology Collaborative (PAC3) hospital survey, we evaluated variations in staffing models regarding first-line providers and assessed associations with programme volume, acuity of care, and post-operative length of stay (LOS). STUDY DESIGN: The PAC3 hospital survey defined staffing models and resource availability across member institutions. A resource acuity score was derived for each participating acute care cardiology unit. Surgical volume was obtained from The Society of Thoracic Surgeons database. Pearson's correlation coefficients were used to evaluate the relationship between staffing models and centre volume as well as unit acuity. A previously developed case-mix adjustment model for total post-operative LOS was utilised in a multinomial regression model to evaluate the association of APP patient coverage with observed-to-expected post-operative LOS. RESULTS: Surveys were completed by 31 (91%) PAC3 centres in 2017. Nearly all centres (94%) employ APPs, with a mean of 1.7 (range 0-5) APPs present on weekday rounds. The number of APPs present has a positive correlation with surgical volume (r = 0.49, p < 0.01) and increased acuity (r = 0.39, p = 0.03). In the multivariate model, as coverage by APPs increased from low to moderate or high, there was greater likelihood of having a shorter-than-expected post-operative LOS (p < 0.001). CONCLUSIONS: The incorporation of paediatric acute care cardiology APPs is associated with reduced post-operative LOS. Future studies are necessary to understand how APPs impact these patient-specific outcomes.

"Echo pause" for postoperative transthoracic echocardiographic surveillance.

BACKGROUND: No guidelines exist for inpatient postoperative transthoracic echocardiographic (TTE) surveillance in congenital heart disease. We prospectively evaluated indications for postoperative TTEs in patients with congenital heart disease to identify areas to improve upon (Phase 1) and then assessed the impact of a simple pilot intervention (Phase 2). METHODS: We included patients with RACHS-1 (Risk Adjustment for Congenital Heart Surgery) scores of 2 and 3 to keep the cohort homogenous. During Phase 1, we collected data prospectively to identify postoperative TTEs for which there were no new findings and no associated clinical management decisions ("potentially redundant" TTEs). During Phase 2, prior to placement of a TTE order, an "Echo Pause" was performed during rounds to prompt review of prior TTE results and indication for the current order. The number of "potentially redundant" TTEs during Phase 1 vs. Phase 2 was compared. RESULTS: During Phase 1, 98 postoperative TTEs were performed on 51 patients. Potentially "redundant" TTEs were identified in two main areas: (a) TTEs ordered to evaluate pericardial effusion and (b) TTEs ordered with the indication of "postoperative," "follow-up," or "discharge" in the setting of a prior complete postoperative TTE and no apparent change in clinical status. During Phase 2, 101 TTEs were performed on 63 patients. The number of "potentially redundant" TTEs decreased from 14/98 (14%) to 5/101 (5%) (P = .026). CONCLUSION: Our results suggest that the number of "potentially redundant" TTEs during inpatient postoperative surveillance of patients with congenital heart disease can be decreased by a simple intervention during rounds such as an "Echo Pause."

Utility of screening echocardiogram after endomyocardial biopsy for identification of cardiac perforation or tricuspid valve injury.

Per protocol, our institution obtains echocardiograms immediately after each EMB to rule out procedural complication. We sought to determine the incidence of echocardiogram-detected cardiac perforation and TV injury and to evaluate the utility of routine screening echocardiogram after each EMB in the current era. At a single center, 99% (1917/1942) EMB performed in 162 patients were immediately followed by an echocardiogram per protocol. There were five newly diagnosed pericardial effusions, and only one required pericardiocentesis. In the three echocardiograms demonstrating new flail TV, only one patient underwent surgical repair 2 months later. This study demonstrates the very low incidence of significant hemopericardium and TV injury after EMB in pediatric heart transplant recipients and argues against the utility of post-EMB echocardiograms to screen solely for procedural complications.

Variability in paediatric cardiac postoperative chest tube management.

Limited evidence exists to guide chest tube management following cardiac surgery in children. We assessed chest tube practice variation by surveying paediatric heart centres to prepare for a multi-site quality improvement project. We summarised management strategies highlighting variability in criteria for chest tube removal between and within centres. This lack of standardisation provides an opportunity for quality improvement.

Collective quality improvement in the paediatric cardiology acute care unit: establishment of the Pediatric Acute Care Cardiology Collaborative (PAC3).

Collaborative quality improvement and learning networks have amended healthcare quality and value across specialities. Motivated by these successes, the Pediatric Acute Care Cardiology Collaborative (PAC3) was founded in late 2014 with an emphasis on improving outcomes of paediatric cardiology patients within cardiac acute care units; acute care encompasses all hospital-based inpatient non-intensive care. PAC3 aims to deliver higher quality and greater value care by facilitating the sharing of ideas and building alignment among its member institutions. These aims are intentionally aligned with the work of other national clinical collaborations, registries, and parent advocacy organisations. The mission and early work of PAC3 is exemplified by the formal partnership with the Pediatric Cardiac Critical Care Consortium (PC4), as well as the creation of a clinical registry, which links with the PC4 registry to track practices and outcomes across the entire inpatient encounter from admission to discharge. Capturing the full inpatient experience allows detection of outcome differences related to variation in care delivered outside the cardiac ICU and development of benchmarks for cardiac acute care. We aspire to improve patient outcomes such as morbidity, hospital length of stay, and re-admission rates, while working to advance patient and family satisfaction. We will use quality improvement methodologies consistent with the Model for Improvement to achieve these aims. Membership currently includes 36 centres across North America, out of which 26 are also members of PC4. In this report, we describe the development of PAC3, including the philosophical, organisational, and infrastructural elements that will enable a paediatric acute care cardiology learning network.

Practice Patterns in Postoperative Echocardiographic Surveillance after Congenital Heart Surgery in Children: A Single Center Experience.

OBJECTIVES: To review current institutional practice and describe factors contributing to variation in inpatient postoperative imaging surveillance after congenital heart surgery. STUDY DESIGN: We reviewed records of all children who underwent congenital heart surgery from June to December 2014. Number and primary indications for postoperative transthoracic echocardiograms (TTEs), providers involved, cardiovascular intensive care unit (CVICU) and total hospital length of stay, and Risk-Adjustment for Congenital Heart Surgery-1 scores were recorded. RESULTS: A total of 253 children (age at surgery: 8 months [2 days-19 years]) received 556 postoperative TTEs (median 1 TTE/patient [1-14]), and 23% had ≥3 TTEs. Fifteen of 556 TTEs (2.7%) revealed a new abnormal finding. The majority of TTEs (59%) were performed in the CVICU (1.5 ± 1.1 TTEs/week/patient), with evaluation of function as the most common indication (44%). Attending physician practice >10 years was not associated with fewer TTEs (P = .12). Patients with ≥3 TTEs had higher Risk-Adjustment for Congenital Heart Surgery-1 scores (P = .001), longer CVICU lengths of stay (22 vs 3 days; P < .0001), longer overall hospitalizations (28 vs 7 days; P < .0001), and a higher incidence of mechanical circulatory support (10% vs 0%; P < .0001) than those with <3 TTEs. Eight patients with ≥3 TTEs did not survive, compared with 3 with <3 TTEs (P = .0004). CONCLUSIONS: There was wide intra-institutional variation in echocardiographic use among similar complexity surgeries. Frequency of postoperative echocardiographic surveillance was associated with degree of surgical complexity and severity of postoperative clinical condition. Few studies revealed new abnormal findings. These results may help establish evidence-based guidelines for inpatient echocardiographic surveillance after congenital heart surgery.

Decompressing vein and bilateral superior venae cavae in a patient with hypoplastic left heart syndrome.

The levoatrial cardinal vein (LACV), first described in 1926, acts as a decompressing vessel for pulmonary venous return in cases of severe left-sided obstruction with an intact or significantly restrictive atrial septum. The LACV and the persistent left superior vena cava (LSVC) are thought to share similar embryologic origins. To challenge this notion, we present a unique case of a neonate with hypoplastic left heart syndrome, cor triatriatum, and a decompressing LACV in the presence of bilateral superior venae cavae.

Prenatal tricuspid valve size as a predictor of postnatal outcome in patients with severe pulmonary stenosis or pulmonary atresia with intact ventricular septum.

INTRODUCTION: Tricuspid valve (TV) size at birth correlates with intervention strategy in patients with severe pulmonary stenosis (SPS) or pulmonary atresia/intact ventricular septum (PA/IVS). Prenatal features that might predict postnatal TV size have not been well studied. We hypothesized that prenatal echocardiographic measurements predict the postnatal TV Z-score in fetuses with SPS and PA/IVS. MATERIALS AND METHODS: We identified 16 neonates (gestational age 28 ± 4.8 weeks) with a fetal diagnosis of SPS or PA/IVS from 2001 to 2010. Measurements were performed offline. ROC (receiver operating characteristic) analysis was used to generate AUC (areas under the curve) for each of the variables. RESULTS: AUC was 0.94 for tricuspid to mitral valve (TV/MV) ratio, 0.88 for TV Z-score, and 0.85 for TV inflow duration. A cut-off value of >0.63 for TV/MV yielded a sensitivity of 78%, specificity of 100% for predicting postnatal TV Z-score >-3. Neonates with TV Z-score ≥-3 and all fetuses with antegrade flow across the pulmonary valve or more than moderate tricuspid regurgitation had biventricular circulation in follow-up. CONCLUSION: Fetal TV/MV >0.63 predicts favorable TV Z-score at birth in patients with SPS and PA/IVS. Antegrade pulmonary valve flow and more than moderate tricuspid regurgitation also conferred a favorable outcome.

Early Wound and Sternal Management Following Pediatric Cardiac Surgery.

Early postoperative wound management following congenital heart surgery remains an area without equipoise. Precautionary restrictions can impact quality of life, development, and delay access to other needed care. The influence of different practices on wound healing and complications is unknown. We surveyed Pediatric Acute Care Cardiology Collaborative member centers regarding postoperative wound closure, wound vacuum-assisted closure (VAC) use, sternal precautions, and restrictions in the early postoperative period. We analyzed responses using descriptive statistics. Responses were submitted by 35/46 (76%) centers. Most centers perform primary skin closure with subcutaneous sutures. Wound covers are removed after 48 h at 43% (15/35) of centers and after ≥72 h at 34% (12/35) of centers. For delayed sternal closure, 16 centers close skin with interrupted, externalized sutures, 5 utilize wound VAC-assisted closure, and 12 use variable practices. Generally, 33 centers use wound VACs for wound care. Patient selection for VAC use and length of therapy varies. We found great variability in duration of sternal precautions and in activity, bathing, and submersion restrictions. Finally, 29 centers require a waiting period between cardiothoracic surgery and other surgeries such as tracheostomy or gastrostomy tube placement. Postoperative wound and sternal management lack consistency across North American pediatric heart institutes. Some restrictive practices may prolong length of stay and/or negatively impact quality of life and neurodevelopment. Practices may also impact wound infection rates. Research linking practices with clinical outcomes is needed to better define standards of care and reduce potential negative consequences of overly conservative or aggressive practices.

Mind the Gap! Working Toward Gender Equity in Pediatric and Congenital Heart Disease: Present and Future.

Evidence from medicine and other fields has shown that gender diversity results in better decision making and outcomes. The incoming workforce of congenital heart specialists (especially in pediatric cardiology) appears to be more gender balanced, but past studies have shown many inequities. Gender-associated differences in leadership positions, opportunities presented for academic advancement, and recognition for academic contributions to the field persist. In addition, compensation packages remain disparate if evaluated based on gender with equivalent experience and expertise. This review explores these inequities and has suggested individual and institutional changes that could be made to recruit and retain women, monitor the climate of the institution, and identify and eliminate bias in areas like salary and promotions.

Natural history of exercise function in patients with Ebstein anomaly: A serial study.

BACKGROUND: The clinical manifestations of Ebstein anomaly (EA) vary greatly; criteria for surgical intervention remain undefined. Decisions regarding surgical intervention in asymptomatic/mildly symptomatic patients would be helpfully informed by a detailed, quantitative understanding of the natural history of exercise intolerance in these patients. However, past studies of exercise function in EA have been of a cross-sectional, rather than a serial, nature. We, therefore, analyzed serial cardiopulmonary exercise (CPX) tests from patients with unrepaired EA to better appreciate the natural history of their exercise function. METHODS: All patients with EA who had had at least 2 CPX tests, separated by at least 6 months, between November 2002 and October 2010 were identified. Patients with prior tricuspid valve surgery were excluded from the study. RESULTS: Cardiopulmonary exercise data from 23 patients (64 CPX tests; 2.8 ± 1.0 tests/patient) were analyzed. The median time interval between the first and last CPX tests was 3.3 (range, 0.6-7.3) years. The percentage of predicted peak oxygen consumption declined slowly (1.87 ± 8.04 percentage points/y) during the follow-up period. The decline was more pronounced (3.04 ± 6.78 percentage points/y) in patients <18 years old. On multivariate modeling, only the change in oxygen pulse at peak exercise (a surrogate for forward stroke volume) and the change in peak heart rate over time emerged as statistically significant correlates of the change in percentage of predicted peak oxygen consumption. CONCLUSION: The exercise function of patients with EA tends to deteriorate over time. This deterioration appears to be related to a progressive decline in their ability to augment their forward stroke volume and heart rate during exercise.

Prenatal diagnosis of atrial restriction in hypoplastic left heart syndrome is associated with decreased 2-year survival.

OBJECTIVE: To compare the course of hypoplastic left heart syndrome (HLHS) patients diagnosed prenatally with any degree of atrial restriction with those without evidence of atrial restriction. DESIGN: Retrospective, cohort. METHODS: Prenatally diagnosed HLHS patients from August 1999 to January 2009 were categorized as nonrestrictive versus restrictive, defined by left atrial hypertension on pulmonary venous Doppler and/or an intact interatrial septum. RESULTS: Of 73 total fetal patients identified, 49 were live-born. Survival at 2 years was 29/35 [83% confidence interval (CI): 59.5%-88.9%] for the nonrestrictive group and 6/14 (43% CI: 17.7%-6.0%) for the restrictive group (p<0.0001). Of those who underwent stage 1 palliation (35 with nonrestrictive and 10 with restrictive atrial septa), both groups had a similar incidence of preoperative acidosis and need for ventilation and inotropic support. Postoperatively, there was no difference between groups in ventilator days, length of stay, or survival to discharge. There was decreased survival at 2 years in the restrictive group, 60% (CI: 26.2%-87.8%) versus 83% (CI: 66.4%-93.4%) in the nonrestrictive group. Furthermore, a disproportionate number of interstage deaths was evident in the restrictive group. CONCLUSIONS: Prenatal presence of any degree of atrial septal restriction in the setting of HLHS confers a significant survival disadvantage, with increases in both early and late mortality.