Aortic valve leaflets are asymmetric and correlated with the origin of coronary arteries.

Background: Asymmetry of the aortic valve leaflets has been known since Leonardo Da Vinci, but the relationship between size and shape and origin of the coronary arteries has never been examined. Our aim was to evaluate this anatomy in a population of pediatric patients using a cross-sectional study design. Methods: Consecutive pediatric patients with trans-esophageal echocardiography (TEE), with or without trans-thoracic echocardiography (TTE), were included in our study. Exclusion criteria: (I) bicuspid aortic valve; (II) aortic valve stenosis; (III) hypoplasia of aortic valve annulus, or aortic root; (IV) truncal valve; (V) coronary artery atresia; (VI) previous surgery on aortic valve and/or coronary arteries. In pre-operative TTE and intra-operative TEE inter-commissural distance and length of aortic valve leaflets were measured in short axis view in the isovolumic phase of systole. Echocardiography investigations, anonymized and randomly coded, were independently reviewed by at least two readers. Echocardiography, angiography, cardiac computed tomography (CT) scan and magnetic resonance imaging (MRI), and operative notes were reviewed to identify origin of coronary arteries. Results: Two hundred sixty-one pediatric patients were identified, 93 excluded per our criteria, leaving 168 patients, age 2.6±4.3 years, weight 12.87±17.34 kg, 128 (76%) with normal and 40 (24%) with abnormal coronary arteries. In TTE and TEE measurements the non-coronary leaflet had larger area (P<0.001), while the right and left had equal areas, but different shape, with the left leaflet longer (P<0.001) and narrower (P=0.005) than the right. With the major source of blood flow from the right coronary sinus, the non-coronary leaflet was still the longest. However, there was no statically significant difference between the size and shape previously observed between the right and left leaflets. Conclusions: Our study showed asymmetry of size and shape among aortic valve leaflets, and a relationship with coronary artery origin. The complex aortic root anatomy must be approximated to optimize function of any surgical repair. These findings also may prove useful in the pre-operative definition of coronary artery anatomy and in the recognition of coronary artery anomalies.

Kaposiform lymphangiomatosis presenting with a Group A Streptococcus pericardial effusion.

A 4-year-old child was transferred to the paediatric intensive care unit with acute respiratory failure following 4 days of fever, nausea and vomiting. Chest X-ray on admission had an enlarged cardiac silhouette and transthoracic echo confirmed a large pericardial effusion. An emergent pericardiocentesis was performed at bedside which drained nearly 1000 mL of purulent fluid. Postdrainage course was complicated by acute systolic and diastolic heart failure, thrombocytopenia and acute renal failure. A chest CT and MRI were concerning for a diffuse mediastinal soft-tissue density, so the patient underwent interventional radiology-guided biopsy complicated by haemorrhage requiring mediastinal exploration and subtotal thymectomy. Histopathology revealed changes consistent with kaposiform lymphangiomatosis and MRI demonstrated involvement of the lumbar spine and right hip. Following a course of intravenous antibiotics, the patient was started on sirolimus and prednisolone and ultimately discharged home.

Effect of Fluid Bolus on Clinical Outcomes in Very Low Birth Weight Infants.

OBJECTIVE: Administration of fluid bolus in very low birth weight (VLBW) infants is a common practice in the NICU, but one without clear evidence demonstrating benefits in clinical outcomes. On the contrary, recent observational studies have suggested a potential detrimental effect of empiric fluid bolus in preterm infants, especially in the absence of clear indications. The aim of this study was to assess the impact of fluid bolus on various clinical outcomes in VLBW infants. METHODS: Retrospective cohort study of VLBW infants born at ≤34 weeks' gestation and/or ≤1500-g birth weight at a single level III NICU from January 1, 2008, to December 31, 2013, and who received at least one fluid bolus within the first 48 hours of life. Outcomes studied were in-hospital mortality, need for home oxygen, incidence of chronic lung disease (CLD), prevalence of patent ductus arteriosus (PDA), and intraventricular hemorrhage (IVH). RESULTS: Of 516 infants, 112 (21.7%) received a fluid bolus within the first 48 hours of life for various indications. Propensity models suggested no statistical difference for CLD or mortality, but exposed infants had an increased incidence of home on oxygen (p = 0.018), PDA prevalence (p = 0.008), and IVH prevalence (p = 0.038). CONCLUSIONS: Fluid bolus in the first 48 hours of life may be associated with increased incidence of need for home oxygen and higher prevalence of PDA and IVH in VLBW infants. Future studies are needed to address these important adverse outcomes.

Synthesis and antimicrobial evaluation of nitazoxanide-based analogues: identification of selective and broad spectrum activity.

A library composed of nitazoxanide-based analogues was synthesized and assayed for increased antibacterial efficacy against the pyruvate-ferredoxin oxidoreductase (PFOR) using microorganisms Helicobacter pylori, Campylobacter jejuni and Clostridium difficile. Derivatives were found to recapitulate and improve activity against these organisms and select analogues were tested for their ability to disrupt the PFOR enzyme directly. The library was also screened for activity against staphylococci and resulted in the identification of analogues capable of inhibiting both staphylococci and all PFOR organisms at low micromolar minimum inhibitory concentrations with low toxicity to human foreskin cells.

Biological activity of modified and exchanged 2-amino-5-nitrothiazole amide analogues of nitazoxanide.

Head group analogues of the antibacterial and antiparasitic drug nitazoxanide (NTZ) are presented. A library of 39 analogues was synthesized and assayed for their ability to suppress growth of Helicobacter pylori, Campylobacter jejuni, Clostridium difficile and inhibit NTZ target pyruvate:ferredoxin oxidoreductase (PFOR). Two head groups assayed recapitulated NTZ activity and possessed improved activity over their 2-amino-5-nitrothiazole counterparts, demonstrating that head group modification is a viable route for the synthesis of NTZ-related antibacterial analogues.