Maternal hypothyroidism may be associated with CHD in offspring.

OBJECTIVES: This study tested whether mothers with maternal hypothyroidism have increased odds of CHD in their offspring, and examined the relationship between CHD, maternal thyroid function, and nausea and vomiting in pregnancy. BACKGROUND: Maternal hypothyroidism increases the risk for foetal demise and prematurity and can have a negative impact on neurodevelopment. Prior studies have postulated a relationship between maternal thyroid function, CHD, and maternal nausea and vomiting in pregnancy. METHODS: A cross-sectional case-control study was conducted over a 17-month period to obtain a history of maternal thyroid status and nausea and vomiting in pregnancy. Paediatric echocardiograms were evaluated for CHD by a blinded paediatric cardiologist. Logistic regression analysis was performed to examine the association between CHD and maternal hypothyroidism. RESULTS: Of the 998 maternal-child pairs, 10% (98/998) of the mothers reported a history of prenatal hypothyroidism. The overall prevalence of CHD in the study sample was 63% (630/998). Mothers with a history of hypothyroidism were significantly more likely to have offspring with CHD compared with mothers without a history of hypothyroidism (72 versus 62%; p=0.04). The adjusted odds ratio (95% confidence interval) of CHD in offspring associated with reported maternal hypothyroidism was 1.68 (1.02-2.78). CONCLUSION: This study suggests that maternal hypothyroidism is a risk factor for the development of CHD. Further prospective investigations are necessary to confirm this association and delineate pathogenic mechanisms.

Infective Endarteritis and Mycotic Pseudoaneurysms in a Pediatric Patient With Aortic Coarctation.

An 11-year-old boy presented with Staphylococcus aureus infective endarteritis and mycotic pseudoaneurysms within the context of a previously undiagnosed aortic coarctation. He had an urgent resection of the pseudoaneurysm and coarctation repair. Nuances to his initial diagnosis and key learning points related to the complication of pseudoaneurysm are discussed.

The Impact of Infective Endocarditis Prophylaxis Recommendations on the Practices of Pediatric and Adult Congenital Cardiologists.

BACKGROUND: Compliance with the April 2007 American Heart Association (AHA) infective endocarditis (IE) guidelines is not well described. We sought to evaluate the impact of these guidelines on the clinical practices of pediatric and adult congenital cardiologists. METHODS: We conducted a 2-centre retrospective cohort study, including patients who had at least 1 outpatient cardiology visit after April 1, 2008 and had 1 of 11 prespecified high- or low-risk congenital cardiac lesions. High-risk lesions required prophylaxis per the AHA guidelines; low-risk patients no longer required prophylaxis. Cardiology clinic letters were reviewed to determine if antibiotic prophylaxis and oral hygiene were addressed and whether prophylaxis was recommended. Comparisons were made before April 2007 vs at least 1 year after guideline publication. RESULTS: We included 238 high-risk and 201 low-risk patients. IE prophylaxis was recommended for all study patients before April 2007. After April 2008, IE prophylaxis recommendations were reduced by 44.9% for low-risk patients (P < 0.0001) and 9.3% for high-risk patients (P = 0.0156). IE prophylaxis recommendations were documented in the medical record of 92% of patients (95% confidence interval, 88%-95%) before April 2007 vs 81% (77%-84%) after April 2008. Oral hygiene was emphasized for only 44% and 28% of patients before and after guideline revision (P = 0.0005). CONCLUSIONS: The 2007 AHA guidelines resulted in significantly fewer recommendations for IE prophylaxis in low-risk patients. However, cardiologists continue to recommend prophylaxis for some low-risk patients and advise some high-risk patients against prophylaxis. These findings suggest disagreement or uncertainty within the cardiology community regarding current IE guidelines.

Echocardiographic assessment of ventricular function in pediatric patients: a comprehensive guide.

Assessment of ventricular function is an important part of every echocardiographic examination. Specific pediatric guidelines on quantification of ventricular function are available, but technology evolves quickly and it generally takes long before newer techniques are integrated into routine clinical practice and are adopted by the guidelines. In the current overview, we would like to present our experience with integrating newer echocardiographic techniques for assessing ventricular function in children using a comprehensive state-of-the-art echocardiographic functional protocol. This protocol is used for specific patient populations such as pediatric patients with cardiomyopathy, post-transplant patients and oncology patients. We present the practical aspects of the protocols, their rationale and how this can be applied in clinical practice.

Recurrent exacerbations of protein-losing enteropathy after initiation of growth hormone therapy in a Fontan patient controlled with spironolactone.

Protein-losing enteropathy (PLE) is a rare, but serious complication in single ventricle patients after Fontan palliation, and is associated with a 5-year mortality of 46%. We describe a patient with PLE after Fontan palliation who achieved remission with high-dose spironolactone (an aldosterone antagonist), but had three exacerbations each temporally correlated with the use of growth hormone (an aldosterone agonist). Because of the opposing mechanisms of action of these two medications, caution might be indicated when using growth hormone for patients with PLE who are successfully treated with spironolactone.

Effects of stretch on work from fast and slow muscles of mice: damped and undamped energy release.

Stretching active muscle increases the work performed during subsequent shortening. The effects of a preceding stretch on work done by the undamped or lightly damped series compliance (SC) and by the contractile component (CC), which includes cross bridges and damped elements, were assessed using mouse soleus (slow) and extensor digitorum longus (fast) muscles with limited tendon. Increasing stretch amplitude (0-10% fibre length) increased work done by the SC up to a limit, but did not effect work done by the CC. Increasing stretch velocity (10-100% Vmax) had almost no effect on work done by either component. Increasing the delay between the end of stretch and onset of shortening (0-60 ms) caused a decrease in SC work, with no effect on CC work. Recoil of the SC was responsible for 50-70% of the total work done during shortening after stretch. Usually only 10-40% of the energy imparted during the stretch was recovered as work during subsequent shortening; large stretches and long delays between stretch and shortening further reduced this recovery by one third to one fifth. Results are interpreted in the context of a loss of energy stored in the SC owing to forcible detachment of cross bridges with large stretches and cyclic detachment with long delays.