Novel Metabolites Are Associated With Thrombosis After Cardiac Surgery in Children With Congenital Heart Disease.

BACKGROUND: Thrombosis is a major complication after cardiac surgery in children with congenital heart disease. The mechanisms underlying thrombosis development remain poorly understood. We aimed to identify novel circulating metabolites before cardiac surgery that are associated with thrombosis after surgery in children with congenital heart disease. METHODS: In this prospective cohort study, all blood samples were drawn right before surgical incision and after the induction of anesthesia, and plasma was separated immediately under 4 °C. Untargeted metabolomic data were measured by Metabolon in plasma from children (age range, 0 days-18 years) with congenital heart disease undergoing cardiac surgery. The primary outcome was thrombosis within 30 days of surgery or before discharge. Associations of individual metabolites with thrombosis were assessed with logistic regression with false discovery rate correction for multiple comparison and adjustment for clinical characteristics; elastic net regression was used to select a prediction model. RESULTS: Out of 1115 metabolites measured in samples from 203 children, 776 met the quality control criteria. In total, 25 children (12.3%) developed thrombosis. Among the 776 metabolites, 175 were significantly associated with thrombosis (false discovery rate Q<0.05). The top 3 metabolites showing the strongest associations with thrombosis were eicosapentaenoate, stearidonate, and andro steroid monosulfate C19H28O6S (false discovery rate, 0.01 for all). Pathway analysis showed that the pathways of nicotinate and nicotinamide metabolism and glycerophospholipid metabolism were enriched (false discovery rate, 0.003 for both) and had significant impact on the development of thrombosis. In elastic net regression analysis, the area under the receiver operating-characteristic curve of a prediction model for thrombosis was 0.969 in the training sample (70% of the total sample) and 0.833 in the testing sample (the remaining 30%). CONCLUSIONS: We have identified promising novel metabolites and metabolic pathways associated with thrombosis. Future studies are warranted to confirm these findings and examine the mechanistic pathways to thrombosis.

Cardiovascular CT for evaluation of single-ventricle heart disease: risks and accuracy compared with interventional findings.

OBJECTIVE: We sought to evaluate the risk and image quality from cardiovascular CT in patients across all stages of single-ventricle palliation, and to define accuracy by comparing findings with intervention and surgery. METHODS: Consecutive CT scans performed in patients with single-ventricle heart disease were retrospectively reviewed at a single institution. Diagnosis, sedation needs, estimated radiation dose, and adverse events were recorded. Anatomical findings, image quality (1-4, 1=optimal), and discrepancy compared with interventional findings were determined. Results are described as medians with their 25th and 75th percentiles. RESULTS: From January, 2010 to August, 2015, 132 CT scans were performed in single-ventricle patients of whom 20 were neonates, 52 were post-Norwood, 15 were post-Glenn, and 45 were post-Fontan. No sedation was used in 76 patients, 47 were under minimal or moderate sedation, and nine were under general anaesthesia. The median image quality score was 1.2. The procedural dose-length product was 24 mGy-cm, and unadjusted and adjusted radiation doses were 0.34 (0.2, 1.8) and 0.82 (0.55, 1.88) mSv, respectively. There was one adverse event. No major and two minor discrepancies were noted at the time of 79 surgical and 10 catheter-based interventions. CONCLUSIONS: Cardiovascular CT can be performed with a low radiation exposure in patients with single-ventricle heart disease. Its accuracy compared with that of interventional findings is excellent. CT is an effective advanced imaging modality when a non-invasive pathway is desired, particularly if cardiac MRI poses a high risk or is contraindicated.

Evidence That High Catecholamine Levels Produced by Pheochromocytoma May be Responsible for Tako-Tsubo Cardiomyopathy.

Tako-tsubo cardiomyopathy (TC) is a novel form of acute heart failure, characterized by regional left ventricular dysfunction without coronary artery obstruction, and usually triggered by a stressful event. Excessive circulating catecholamines have been implicated in the pathophysiology of this condition. This report documents the unusual occurrence of acute TC events in 2 male subjects of disparate ages, 16 and 66 years, for whom subsequent investigation in both led to the unexpected discovery of catecholamine-producing pheochromocytoma. Marked elevation of plasma catecholamines (epinephrine, norepinephrine, and dopamine) was present in both subjects and were remarkably similar to those previously reported in female patients with TC triggered by emotional stress. These observations show a common link between TC occurrence and elevated catecholamine levels in both male and female patients and, therefore, support the hypothesis that excessive levels of catecholamines may be involved in the pathophysiology of TC independent of age or gender.

Selective use of cardiac computed tomography angiography: an alternative diagnostic modality before second-stage single ventricle palliation.

OBJECTIVES: To assess the accuracy and risk of substituting cardiac computed tomography for cardiac catheterization in select patients for evaluation of anatomy before second-stage single ventricle palliation. METHODS: This is a retrospective review of consecutive diagnostic cardiac catheterization (n=16) and computed tomography studies (n=16) performed before second-stage single ventricle palliation from March 2010 to July 2012 at a single institution. Risk (anesthesia, vascular access, contrast, and radiation exposure), accuracy, and postoperative course were compared. Nonparametric analysis was used to compare differences in group medians. RESULTS: General anesthesia was used for 16 of 16 cardiac catheterization studies and 1 of 16 computed tomography studies. Vascular access was central venous and/or arterial for all cardiac catheterization studies and a peripheral intravenous line for all computed tomography studies. Median age- and size-adjusted radiation dose was 14.0 mSv for cardiac catheterization and 1.1 mSv for computed tomography. Contrast dose was 4.8 mL/kg for the cardiac catheterization group and 2 mL/kg for the computed tomography group. There were no computed tomography discrepancies and 1 discrepancy between cardiac catheterization and surgical findings. There were 8 adverse events in 6 patients in the cardiac catheterization group and 1 adverse event in the computed tomography group. There was no difference between groups in postoperative course or need for repeat intervention. CONCLUSIONS: Cardiac computed tomography and cardiac catheterization are equally accurate for evaluation of anatomy before second-stage single ventricle palliation when compared with surgical findings. Computed tomography may be the preferred test in select patients because of decreased vascular access and anesthesia risk, lower radiation and contrast exposure, and fewer adverse events.