Echocardiographic Screening for Postoperative Pericardial Effusion in Children.

Pericardial effusion (PE) after cardiac surgery can be life threatening without timely detection, and the optimal screening method is unknown. We sought to evaluate the role of a surveillance echocardiogram on postoperative day 10 (± 2), determine the incidence of postoperative PE, and identify risk factors. We conducted a retrospective cohort study including all pediatric patients who underwent open heart surgery at a single institution over a 7-month period. To identify risk factors for PE, medical records of patients with PE detected within 6 weeks after surgery (cases) were compared with patients without PE (controls). Of 203 patients, 52 (26%) had PE within 6 weeks; 42 (81%) were trivial-small and 10 (19%) were moderate-large. Twenty-nine (56%) were first detected within 7 days post-operatively, including all cases developing cardiac tamponade (n = 3). An echocardiogram was done 10 (± 2) days post-operatively in 41/52 cases, of which 12/41 (29%) did not have a PE at this time, 24/41 (59%) had a trivial-small PE, and 5/41(12%) had a moderate-large PE; 2 of the latter had no prior detected PE. Closure of an atrial septal defect had the highest incidence of PE (42%). PE cases were associated with postoperative nasopharyngeal detection of a respiratory virus (OR 3.8, p = 0.03). In conclusion, the majority of PE cases were detected within 7 days post-operatively, including all cases subsequently developing cardiac tamponade. Day 10 echocardiography infrequently detected a moderate or large effusion that had previously gone undiagnosed. A positive perioperative nasopharyngeal aspirate for a respiratory virus was associated with postoperative PE.

High-frequency vs. conventional ventilation at the time of CDH repair is not associated with higher mortality and oxygen dependency: a retrospective cohort study.

PURPOSE: The VICI-trial reported that in patients with congenital diaphragmatic hernia (CDH), mortality or bronchopulmonary dysplasia (BPD) were equivalent using conventional mechanical ventilation (CMV) and high-frequency oscillatory ventilation. The purpose of this study was to determine if the mode of ventilation at the time of CDH repair affected mortality or oxygen dependence at 28 days. METHODS: We performed a retrospective cohort study of infants born wih CDH from 1991 to 2015. A generalized linear model was applied to the data using a propensity score analysis. RESULTS: Eighty patients met the inclusion criteria; at the time of surgery 39 (48.8%) patients were on HFV and 41 (51.3%) patients were on CMV. In the HFV group, 16 (47.1%) patients remained oxygen dependent and there were 5 (12.8%) deaths at 28 days. In the CMV group, 5 (12.2%) patients remained oxygen dependent at 28 days but none had died. The base model demonstrated that the HFV group had increased rates of oxygen dependence [OR = 6.40 (2.13, 22.2), p = 0.002]. However, after propensity score analysis, we found no difference between HFV and CMV. CONCLUSION: Our study suggests that in infants with CDH, there is no significant difference between HFV and CMV in oxygen dependency or death.

The presence of a hernia sac in isolated congenital diaphragmatic hernia is associated with less disease severity: A retrospective cohort study.

INTRODUCTION: We aimed to determine if the presence of a hernia sac in neonates with isolated congenital diaphragmatic hernia (CDH) was associated with better clinical outcomes. METHODS: We performed a retrospective cohort study of infants with isolated CDH from 1991 to 2015. Primary outcome measures were oxygen-dependence and mortality at 28 days. Secondary measures were: inhaled nitric oxide use, vasoactive medication use, ventilator support, and recurrence rates. RESULTS: Seventy-one patients met the inclusion criteria: 14 patients (19.7%) had a hernia sac, and 57 patients (80.3%) did not. Mortality did not differ between the 2 groups [0 of 14 versus 3 of 57 (5.3%) (p = 1.000)]. Hernia sac patients had similar oxygen-dependence after 28 days [1 of 14 (7.1%) versus 14 of 57 (24.6%) (p = 0.273)]. Hernia sac children required less iNO (0.64 ±â€¯2.41 vs. 6.35 ±â€¯12.2 days, p = 0.002), vasoactive medications (2.79 ±â€¯3.07 vs. 5.36 ±â€¯5.52, p = 0.027), and time on ventilation (7.62 ±â€¯6.12 vs. 15.9 ±â€¯19.2, p = 0.010). Hernia sac children had similar recurrence rates within 2 years [0 of 14 versus 7 of 57 (12.3%) (p = 0.331)]. CONCLUSION: The presence of a hernia sac was not associated with lower rates of oxygen dependency or death at 28 days but was associated with decreased inhaled nitric oxide, vasoactive medication, and ventilator use. LEVEL OF EVIDENCE: III.

Hypoplastic Left Heart Syndrome Is Not a Predictor of Worse Intermediate Mortality Post Fontan.

BACKGROUND: An increasing proportion of those living with single ventricle physiology have hypoplastic left heart syndrome (HLHS). Our objective was to assess the association between HLHS and outcomes post Fontan operation. METHODS: All pediatric patients who underwent a Fontan procedure at the University of Alberta between 1996 and 2016 were included. Follow-up clinical data collected included early and late surgical or catheter reintervention, echocardiography, and long-term transplant-free survival. Characteristics were compared between those with and without HLHS, and the association between outcomes and HLHS were assessed. RESULTS: A total of 320 children (median age 3.3 years, interquartile range 2.8 to 3.9 years; 121 [43.4%] female) underwent a Fontan procedure over the course of the study. Nearly one third of subjects had HLHS (107, 33.4%). Patients with HLHS were more likely to have abnormal ventricular function (19.6% versus 7.0%, p = 0.003) and worse than mild atrioventricular valve (AVV) regurgitation (23.4 versus 9.2%, p = 0.001) preoperatively. HLHS was not predictive of in-hospital Fontan failure (odds ratio 0.82, 95% CI 0.28, 2.39), late reintervention (hazard ratio [HR] 1.08, 95% CI 0.66, 1.76), or transplant-free survival (HR 1.58, 95% CI 0.72, 3.44). Subjects with HLHS were more likely to have more than mild AVV regurgitation (31.6% versus 13.3%, p = 0.028) and abnormal ventricular function (29.8% versus 10.7%, p < 0.0001) at late follow-up. CONCLUSIONS: Patients with HLHS who survive to the Fontan procedure do no worse with the operation than those with other anatomy. Given worse late ventricular function and AVV regurgitation, equivalent survival may not persist throughout a patient's life course.

Stress perfusion magnetic resonance imaging to detect coronary artery lesions in children.

BACKGROUND: Stress perfusion cardiovascular magnetic resonance (CMR) is used widely in adult ischemic heart disease, but data in children is limited. We sought to evaluate feasibility, accuracy and prognostic value of stress CMR in children with suspected coronary artery disease (CAD). METHODS: Stress CMR was reviewed from two pediatric centers over 5 years using a standard pharmacologic protocol. Wall motion abnormalities, perfusion deficits and late enhancement were correlated with coronary angiogram (CAG) when available, and clinical status at 1 year follow-up for major adverse cardiovascular events (MACE; coronary revascularization, non-fatal myocardial infarction and death due to CAD) was recorded. RESULTS: Sixty-four stress perfusion CMR studies in 48 children (10.9 ± 4.8 years) using adenosine; 59 (92%) and dipyridamole; 5 (8%), were reviewed. Indications were Kawasaki disease (39%), post arterial switch operation (12.5%), post heart transplantation (12.5%), post anomalous coronary artery repair (11%), chest pain (11%), suspected myocarditis or CAD (3%), post coronary revascularization (3%), and others (8%). Twenty-six studies were performed under sedation. Of all studies performed, 66% showed no evidence of ischemia or infarction, 28% had perfusion deficits and 6% had late gadolinium enhancement (LGE) without perfusion deficit. Compared to CAG, the positive predictive value (PPV) of stress CMR was 80% with negative predictive value (NPV) of 88%. At 1 year clinical follow-up, the PPV and NPV of stress CMR to predict MACE were 78 and 98%. CONCLUSION: Stress-perfusion CMR, in combination with LGE and wall motion-analysis is a feasible and an accurate method of diagnosing CAD in children. In difficult cases, it also helps guide clinical intervention by complementing conventional CAG with functional information.

Effect of hydration status on atrial and ventricular volumes and function in healthy adult volunteers.

BACKGROUND: Assessment of cardiac chamber volumes is a fundamental part of cardiac magnetic resonance (CMR) imaging. While the effects of inter- and intraobserver variability have been studied and have a recognized effect on the comparability of serial cardiac MR imaging studies, the effect of differences in hydration status has not been evaluated. OBJECTIVE: To evaluate the effects of volume administration on cardiac chamber volumes. MATERIALS AND METHODS: Thirteen healthy adults underwent a baseline cardiac MR to evaluate cardiac chamber volumes after an overnight fast. They were then given two saline boluses of 10 ml/kg of body weight and the cardiac MR was repeated immediately after each bolus. RESULTS: From the baseline scan to the final scan there was a significant increase in all four cardiac chamber end-diastolic volumes. Right atrial volumes increased 8.0%, from 61.1 to 66.0 ml/m2 (P<0.001), and left atrial volumes increased 10.0%, from 50.0 to 55.0 ml/m2 (P<0.001). Right ventricular volumes increased 6.0%, from 91.1 to 96.5 ml/m2 (P<0.001), and left ventricular volumes increased 3.2%, from 87.0 to 89.8 ml/m2 (P<0.001). CONCLUSION: Hydration status has a significant effect on the end-diastolic volumes of all cardiac chambers assessed by cardiac MR. Thus, hydration represents a "variable" that should be taken into account when assessing cardiac chamber volumes, especially when performing serial imaging studies in a patient.

MR assessment of abdominal circulation in Fontan physiology.

The Fontan operation allows for longer survival of those born with functionally single ventricle physiology. Although it effectively eliminates cyanosis, increased systemic venous pressure is an unavoidable consequence and low cardiac output is frequent. The abdomen is particularly vulnerable to these alterations in hemodynamics because the hepatic blood flow consists predominantly of portal venous flow, which relies on a low pressure gradient between the portal and hepatic veins. Therefore, any subtle increase in systemic venous pressure will adversely affect the hemodynamic balance of the liver as well as the intestine. As the clinical manifestations and routine laboratory findings of abdominal complications can lag behind the hemodynamic and pathologic changes in the abdominal organs, regular imaging surveillance is critical. Magnetic resonance (MR) provides excellent visualization of both cardiovascular and abdominal systems. It provides robust anatomic and hemodynamic data which can be used for timely implementation of treatment options. In this review paper, we discuss the pathogenesis and MR findings of abdominal complications following the Fontan operation. Specifically we explore the utility of phase-contrast MR for assessment of the abdominal circulation in children following the Fontan palliation.

A practical method of measuring oxygen consumption in children with complex mixing circulations by the use of thermodilution cardiac output studies.

OBJECTIVE: We describe a method to measure oxygen consumption (VO2) and pulmonary vascular resistive index (PVRI) based on thermodilution cardiac output in patients with complex mixing circulations. We apply this method to patients with a bidirectional cavopulmonary anastomosis (BDCPA). We compare our measured VO2 with a predicted VO2 based on a formula using height and weight. METHODS: We reviewed data based on cardiac catheterization and thermodilution cardiac output in a series of 25 catheterizations in patients with BDCPA. We used this data to measure VO2 and PVRI, and looked for a correlation between the predicted and measured VO2. We also assessed whether any other hemodynamic parameter correlated with measured VO2. RESULTS: There was no significant correlation between the predicted and the measured VO2 (correlation coefficient = -0.258, P = .21). We did find a significant correlation in the difference between the measured and predicted VO2 against the measured VO2 such that at a lower measured VO2 the predictive formula tended to overestimate VO2 and at a higher VO2 the formula underestimated VO2 (correlation coefficient = 0.963, P < .0001). Body surface area did not correlate with measured VO2 (correlation coefficient = 0.28, P < .16). Mixed venous oxygen content showed a weak negative correlation with VO2 (correlation coefficient = -0.54, P = .005). CONCLUSIONS: An assessment of PVRI that is based on a predicted VO2 is unreliable in this patient population. No hemodynamic parameter correlated well with VO2. The use of a measured VO2 is necessary in determining PVRI in these patients.

Septic arthritis due to Roseomonas gilardii in an immunocompetent adolescent.

The genus Roseomonas comprises groups of slow-growing, Gram-negative coccobacilli, which only infrequently cause infection in humans. When identified, they are associated with immunocompromised adults, often causing bacteraemia. Due to their rarity, members of this genus can be overlooked or misidentified using automated laboratory identification systems. We report on an immunocompetent adolescent patient who developed septic arthritis due to Roseomonas gilardii following surgery for a sports injury. The isolate was initially misidentified as Bordetella bronchiseptica using the Vitek 2 system, but confirmed as R. gilardii based on 16S rRNA gene sequencing. To the best of our knowledge, this is the first case of a healthy paediatric patient with septic arthritis due to R. gilardii.