Camden Hebson

Features of portal hypertension are associated with major adverse events in Fontan patients: The VAST study

BACKGROUND Chronic congestive hepatopathy is known to cause hepatic fibrosis and portal hypertension in patients post-Fontan operation for single ventricle palliation. The clinical significance of these findings is not clear. We hypothesized that features of portal hypertension would be significantly related to major adverse events. METHODS A retrospective review of 73 adult and pediatric post-Fontan patients referred for a liver evaluation from 2001 to 2011 was performed. The relationship between features of portal hypertension (VAST score ≥2, 1 point each for Varices, Ascites, Splenomegaly or Thrombocytopenia) and a major adverse event (death, need for transplant, or hepatocellular carcinoma) was examined using logistic regression. RESULTS 73 post-Fontan patients (30% female, 73% Caucasian, 66% systemic left ventricle (SLV), mean age 24±11 years, mean interval from Fontan 17±6 years) were included in analysis. Features of portal hypertension (VAST score ≥2) were present in 26 (36%), and there were 19 major adverse events: death (n=12), transplant (n=6), and HCC (n=1). A significant relationship was found between VAST score ≥2 and major adverse events (OR=9.8, 95% CI [2.9-32.7]). After adjusting for time since Fontan, SLV, age, hemoglobin and type of failure, VAST score ≥2 remained significant (OR=9.1, 95% CI [1.4-57.6]). CONCLUSION Fontan patients with features of portal hypertension have a 9-fold increased risk for a major adverse event. Therapies targeted to manage clinical manifestations of portal hypertension, and early referral to heart transplant may help delay major adverse events. Future prospective studies are needed to confirm these findings.

Association of feeding modality with interstage mortality after single-ventricle palliation.

OBJECTIVE Interstage mortality has been reported in 10% to 25% of hospital survivors after single-ventricle palliation. The purpose of this study was to examine the impact of feeding modality at discharge after single-ventricle palliation on interstage mortality. METHODS We conducted a retrospective review of all neonates undergoing single-ventricle palliation from January 2003 to January 2010. A total of 334 patients (90%) survived to hospital discharge, comprising the study group. Preoperative, operative, and postoperative variables were examined, including feeding method at discharge. Multivariate Poisson regression models were constructed to estimate the relative risk of interstage mortality. RESULTS Of 334 patients, 56 (17%) underwent gastrostomy tube ± Nissen. There was a statistically significant increase in interstage mortality for patients who underwent gastrostomy tube ± Nissen compared with patients who did not (relative risk, 2.38; 95% confidence interval, 1.05-5.40; P = .04]). Of the 278 patients who were not fed via a gastrostomy tube ± Nissen, 190 (68%) were fed with nasogastric feedings and 88 (32%) were fed entirely by mouth. There was no difference in interstage mortality between these 2 groups (relative risk, 0.92; 95% confidence interval, 0.31-2.73; P = .89). CONCLUSIONS Neonates undergoing single-ventricle palliation who require gastrostomy tube ± Nissen are at an increased risk of interstage mortality. The need for gastrostomy tube ± Nissen in this population may be a marker for other unmeasured comorbidities that place them at an increased risk of interstage mortality. Discharge with nasogastric feeds does not increase the risk of interstage mortality.

Catheter-measured Hemodynamics of Adult Fontan Circulation: Associations with Adverse Event and End-organ Dysfunctions.

BACKGROUND In heart failure, a high systemic vascular resistance index (SVRI), high central venous pressure (CVP), and low cardiac index (CI) predict poor outcomes. Conversely, late hemodynamic manifestations of failing Fontan circulation and associations with end-organ dysfunction are not well understood. METHODS A retrospective review of right-heart catheterization data of adult Fontan patients between 2002 and 2014 was conducted. Relationships between hemodynamic variables and serious adverse events (death or heart transplant) were examined using the Cox proportional hazard analysis. Correlations between the hemodynamic measurements and signs of end-organ dysfunction (MELD-XI, Child-Pugh, VAST score, estimated glomerular filtration rate [eGFR]) were analyzed. RESULTS Sixty post-Fontan patients (85% systemic left ventricle, 40% atriopulmonary Fontan, mean age of 28 years, and mean time since Fontan operation of 21.9 years) were included. At baseline, those with an event were statistically younger, had lower transcutaneous oxygen saturations, were more likely to have an atriopulmonary Fontan, and were more likely to have a pacemaker. Eighteen experienced a cardiovascularly significant event. Using univariate analysis to compare the event and nonevent groups, mean CI was 2.8 ± 0.9 vs. 2.4 ± 0.5 L/min/m2 (P = .004), and CVP was 18.6 ± 6.5 vs. 16.1 ± 4.3 mmHg (P = .03). However, the statistical significances did not persist in the multivariate model. Higher CVP and pulmonary capillary wedge pressure (PCWP) were associated with higher MELD-XI and Child-Pugh scores, and the VAST score was only associated with PCWP. CONCLUSIONS Symptomatic adult Fontan patients who experienced an event manifested with a higher CI and CVP, although the multivariate Cox proportional hazard analysis did not yield any significant associations. The presences of hepatic dysfunction and portal venous outflow obstruction were associated with a higher CVP and PCWP. Renal dysfunction was prevalent but no statistically significant association between the hemodynamic measurements was identified, although trends toward a higher CVP and transpulmonary gradient were identified.

Severe aortopathy due to fibulin-4 deficiency: molecular insights, surgical strategy, and a review of the literature

Mutations in the EFEMP2 (alias FBLN4) gene, which encodes the extracellular matrix protein fibulin-4, lead to severe aortopathy with aneurysm formation and vascular tortuosity. The disease phenotype, termed autosomal recessive cutis laxa type 1B (ARCL 1B), is rare among heritable connective tissue diseases but becomes more likely when noting family consanguinity and loose, inelastic skin in the patient. Our patient presented with an intercurrent illness exacerbating upper airway obstruction due to compression from a large aortic aneurysm. Genetic testing eventually revealed the causative mutation. She was initially treated with an angiotensin II receptor blocker and beta-blocker and eventually underwent total thoracic aortic replacement via a two-stage elephant trunk-type procedure. She recovered well and is currently asymptomatic but will require lifetime follow-up due to residual vascular tortuosity and aneurysm risk. Conclusion: Better understanding of the importance of transforming growth factor beta signaling in the pathophysiology of aortopathies such as ARCL 1B has led to targeted medical therapies. Specific surgical techniques can lead to optimal outcomes in these patients.

Safe and effective use of a glycemic control protocol for neonates in a cardiac ICU.

Objective: To investigate the safety and efficacy of a hyperglycemia protocol in neonates with critical cardiac illness. Neonates are often regarded as high risk for hypoglycemia while receiving continuous insulin infusions and thus have been excluded from some clinical trials. Design: A retrospective review. Setting: A pediatric cardiac ICU in a tertiary academic center. Interventions: Neonates with critical cardiac illness who developed hyperglycemia were placed on an insulin-hyperglycemia protocol at the attending physician’s discretion. Insulin infusions were titrated based on frequent blood glucose monitoring. Measurements: Critical illness hyperglycemia was defined as a blood glucose less than 140 mg/dL. Hypoglycemia was defined as moderate (⩽ 60 mg/dL) or severe (⩽ 40 mg/dL). Initiating blood glucose, lowest blood glucose during insulin infusion, doses of insulin, duration of insulin, and time to blood glucose greater than 140 mg/dL were evaluated. Main Results: A total of 44 patients were placed on the protocol between January 2009 and October 2011. The majority of insulin infusions were initiated in the early postoperative period (33 of 44, 75%). Moderate hypoglycemia occurred in two patients (4.5%), with blood glucose levels of 49 and 53 mg/dL. No episodes of severe hypoglycemia occurred. A total of 345 discrete blood glucose levels were analyzed; two of these being greater than 60 mg/dL (0.58%). Mean blood glucose prior to starting insulin was 252 ± 45 mg/dL and time until euglycemia was 6.1 ± 3.9 hours. The mean duration of insulin infusion was 24.6 ± 38.7 hours, mean peak dose was 0.10 ± 0.05 units/kg/hour, and mean insulin dose was 0.06 ± 0.02 units/kg/hour. For postoperative patients, mean time after bypass until onset of hyperglycemia was 2.2 ± 2.6 hours. Conclusions: A glycemic control protocol can safely and effectively be applied to neonates with critical cardiac disease. Neonates with critical cardiac illness should be included in clinical trials evaluating the benefits of glycemic control.

Electrocardiographic screening in children with attention-deficit hyperactivity disorder.

Some investigators have suggested that children receiving stimulant medications to manage attention-deficit hyperactivity disorder should undergo screening electrocardiography to identify asymptomatic cardiac disease. However, no study to date has examined the efficacy and costs of this strategy. In the present study we sought to determine the utility of electrocardiographic screening in children with attention-deficit hyperactivity disorder. We reviewed the clinical experience of electrocardiographic screening of subjects with attention-deficit hyperactivity disorder <21 years of age from April to September 2008. Additional cardiac care and testing that resulted from an abnormal initial electrocardiogram were recorded. Screening electrocardiograms were obtained in 1,470 children with attention-deficit hyperactivity disorder and were interpreted as abnormal in 119 subjects (8.1%). Further evaluation of these 119 subjects included 63 transthoracic echocardiograms, 5 stress tests, and 9 Holter monitor studies. Cardiac disease was identified in 5 subjects (0.3% of entire cohort), yielding a positive predictive value of 4.2%. Cardiac diagnoses included ventricular pre-excitation syndrome (n = 2), bicuspid aortic valve (n = 2), and moderate secundum atrial septal defect (n = 1). The mean cost of electrocardiographic screening including further testing for subjects with abnormal initial screen results was

Elevated tricuspid regurgitant velocity as a marker for pulmonary hypertension in children with sickle cell disease: less prevalent and predictive than previously thought?

58 per child. The mean cost to identify a true-positive result was

Four new cases of pediatric thoracic aortic aneurysm (TAA) with review of the molecular genetic basis, utilizing the newly published consensus nomenclature

17,162. In conclusion, electrocardiographic screening for children with attention-deficit hyperactivity disorder can successfully identify cardiac disease in otherwise asymptomatic subjects, although the positive predictive value is low. Ongoing studies are needed to know what role electrocardiographic screening should play in the management of children with attention-deficit hyperactivity disorder.

Late Development of a Gigantic Aneurysm of the Neoaorta After Norwood Palliation

Although elevated tricuspid regurgitant velocity (TRV), an echocardiographic marker for pulmonary hypertension, has previously been tied to mortality in adult patients with sickle cell disease, recent data demonstrated that it correlates poorly with catheterization findings. We describe the largest echocardiographic evaluation of pediatric patients with sickle cell disease to date, specifically the results of a protocol whereby a TRV≥250 cm/s prompted further evaluation. We investigated if elevated TRV would independently identify patients at risk for increased morbidity. A clinical echocardiographic database containing 630 patients with sickle cell disease was retrospectively reviewed; 120 patients (19%) met inclusion criteria and were compared 1:1 to randomly selected age-matched controls from the same database. By multivariate analysis, the elevated TRV cohort did not differ from controls in likelihood of acute chest episodes, hospitalization, or stroke. The study cohort’s mean TRV in fact decreased to 242±33 cm/s at follow-up without a discernible and comprehensive intervention to explain the improvement. Three patients had catheterization-proven pulmonary hypertension. In conclusion, elevated TRV in children with sickle cell disease is less prevalent than previously thought and is not independently associated with increased short-term morbidity.

Complete heart block and echocardiographic abnormalities caused by pyrotechnic chest trauma.

The majority of thoracic aortic aneurysms (TAA) in the pediatric population are due to post repair etiology (iatrogenic). Although rare, underlying inheritable disease and congenital cardiac anomalies represent the most common non-iatrogenic cause of TAA among patients in this age group (1-21 years of age). Herein, we present a case series of 9aortic aneurysms with varying underlying etiology. We discuss the molecular genetic basis of these syndromes in conjunction with the radiological findings and histological description utilizing the newly published consensus criteria article.