Successful Postnatal Tracheobronchoplasty for Unilateral Congenital High Airway Obstruction Syndrome (CHAOS) due to Mainstem Bronchial Atresia.

INTRODUCTION: Unilateral congenital high airway obstruction syndrome (CHAOS) is caused by a complete obstruction of a mainstem bronchus with resulting hyperinflation and accelerated growth of one lung, severe mediastinal shift and hydrops. Spontaneous perforation of the atresia has been observed in CHAOS which allows hydrops to resolve but hyperinflation, mediastinal shift and a critical airway obstruction persists as the perforation is usually pinhole-sized. CASE PRESENTATION: We present a case of unilateral CHAOS presenting at 26 2/7 weeks' with observed-to-expected total lung volume (O/E TLV) of 203% with spontaneous perforation occurring at 28 weeks' with resolution of hydrops but persistence of hyperinflation and mediastinal shift with an O/E TLV of 60.5% on 34 5/7 weeks' magnetic resonance imaging (MRI), successfully managed in a 35 5/7 weeks', 1670 gm, growth restricted baby, by veno-arterial extracorporeal membrane oxygenation (VA ECMO) and resection of the tracheobronchial atresia and tracheobronchoplasty on day of life 5. The baby was separated from ECMO on post-op day 12, required tracheostomy for positive end expiratory pressure (PEEP) for tracheomalacia at 4 months. CONCLUSION: At two years of age, she has met all developmental milestones, has been weaned to room air tracheostomy collar, and is anticipating tracheal decannulation. There is persistent bronchiectasis in the hyperinflated right lung but no malacia. This is the first reported survivor of mainstem bronchial atresia suggesting the importance of preservation of the hyperplastic lung and airway reconstruction to normal long-term outcome.

GATA4 mutations cause human congenital heart defects and reveal an interaction with TBX5.

Congenital heart defects (CHDs) are the most common developmental anomaly and are the leading non-infectious cause of mortality in newborns. Only one causative gene, NKX2-5, has been identified through genetic linkage analysis of pedigrees with non-syndromic CHDs. Here, we show that isolated cardiac septal defects in a large pedigree were linked to chromosome 8p22-23. A heterozygous G296S missense mutation of GATA4, a transcription factor essential for heart formation, was found in all available affected family members but not in any control individuals. This mutation resulted in diminished DNA-binding affinity and transcriptional activity of Gata4. Furthermore, the Gata4 mutation abrogated a physical interaction between Gata4 and TBX5, a T-box protein responsible for a subset of syndromic cardiac septal defects. Conversely, interaction of Gata4 and TBX5 was disrupted by specific human TBX5 missense mutations that cause similar cardiac septal defects. In a second family, we identified a frame-shift mutation of GATA4 (E359del) that was transcriptionally inactive and segregated with cardiac septal defects. These results implicate GATA4 as a genetic cause of human cardiac septal defects, perhaps through its interaction with TBX5.

Left ventricular function and response to enalapril in patients with duchenne muscular dystrophy during the second decade of life.

The role of angiotensin-converting enzyme inhibitors in the management of cardiomyopathy related to Duchenne muscular dystrophy has not been completely defined. The purposes of this study were to describe the response to enalapril and its relation to dystrophin mutation type, ventricular size, or age at the onset of left ventricular (LV) systolic dysfunction. Serial clinical and echocardiographic data from 50 patients with Duchenne muscular dystrophy (aged 10 to 20 years) were retrospectively reviewed. Twenty-seven patients (46%) developed LV systolic dysfunction (mean age 13.2 +/- 2.4 years). Ten (43%) responded to enalapril with the normalization of function. Responders and nonresponders developed LV systolic dysfunction at similar ages (p = 0.91). At the onset of LV systolic dysfunction, only 2 patients (1 responder, 1 nonresponder) had dilated left ventricles. The positive response to enalapril was sustained in 7 patients (median follow-up 23 months, range 5 to 58). No specific mutation was associated with the response to enalapril (p = 0.66) or predictive of the development of LV systolic dysfunction (p = 0.8). In conclusion, 10 of 26 patients (43%) with Duchenne muscular dystrophy responded to the use of enalapril with normalization of the shortening fraction. Age at the onset of LV systolic dysfunction and the type of mutation were not predictors of response to enalapril.

Mitral valve morphology and morbidity/mortality in Shone's complex.

Early echocardiographic studies of 50 patients with Shone's complex were retrospectively examined to identify left-sided cardiac features associated with progressive mitral valve (MV) disease requiring intervention, as well as mortality. Thickened MV leaflets, shortened MV chordae coupled with either thickened MV leaflets or turbulence at or below the MV noted by color Doppler, left ventricular outflow tract obstruction without coarctation of the aorta, and mild or moderate aortic insufficiency were associated with a poor prognosis.

Echocardiographic characteristics of perimembranous ventricular septal defects associated with aortic regurgitation.

Development of aortic regurgitation (AR) can complicate an isolated perimembranous ventricular septal defect (VSD). The objective of this study was to identify echocardiographic features of perimembranous VSDs associated with AR. Echocardiograms were evaluated for the presence of aortic cusp override, aortic cusp movement abnormality, and presence of color flow mapping across the ventricular septum in a standard, parasternal long-axis view. Echocardiograms of 26 patients with isolated VSDs were included in the study, 13 had AR and 13 had no evidence of AR. Aortic cusp override in the apical 5-chamber and subcostal coronal views were correlated with the presence of AR, with high sensitivity and low specificity. Flow across the septum in the parasternal long-axis view was associated with AR, with moderate sensitivity and specificity. Aortic cusp movement abnormalities had high sensitivity and low specificity. Our data indicate that these findings may identify patients with perimembranous VSD susceptible to AR.

Anomalous systemic arterial supply to the lungs: an unusual etiology for cardiomegaly.

Anomalous systemic arterial blood supply to the lungs is a rare anomaly of lung development. It may present with various manifestations that are shared with more commonly encountered congenital and acquired heart diseases. Thus, it may evade early diagnosis or even lead to a wrong diagnosis and treatment. This lesion should be suspected in left ventricular overload conditions in the absence of a clear explanation.