Faculty Bibliography

Persistent fifth arch (PFA) is a rare anomaly that is often underdiagnosed and missed. Different PFA types that have been reported in the literature are systemic-to-systemic type (most common), systemic-to-pulmonary artery (PA), and PA-to-systemic types. The designations of systemic-to-PA or PA-to-systemic are based on if the PFA is a source of PA or systemic blood flow, respectively, in the setting of critical proximal obstruction (pulmonary atresia or aortic atresia). This case describes an unusual PFA, which connects the distal PA to distal ascending aorta; however, it is not associated with critical proximal obstruction, and while it appeared to be an incidental finding in early gestation, progressive serial distal obstruction of the left fourth arch was seen to develop. This case highlights that prenatal diagnosis of PFA is possible and that once a diagnosis is made, serial fetal echocardiograms should be performed to evaluate for evolving lesions.

Background: Complex muscular ventricular septal defects (CMVSD) are often difficult to surgically close and managed by device closure. The pre-intervention imaging is crucial in defining the anatomy and aids in patient selection. We hypothesized that 3D physical and virtual models in patients with CMVSD is feasible, would assist in patient selection and aid in the successful device closure. Methods: Virtual and physical 3D models on 3 patients with CMVSD were generated from CT or MRI data, using Mimics, and 3-Matic software. The first patient had history of complicated and unsuccessful prior device closures, with residual shunt. Two physical models, with and without devices in situ were printed (Figure 1A) for this patient. Two virtual models were generated in the other two patients. Results: The location, size, trabeculations, papillary and muscle bundles were clearly visualized in all patients. The two physical models were extensively studied, resulting in successful device closure of the residual VSD. The virtual model on patient 2 identified RV papillary muscles adjacent to the CMVSD (Figure 1B) precluding device closure. The patient 3 model identified muscle bundles crowding the VSD suggesting potential for spontaneous closure. Conclusion: Construction of 3D models in patients with CMVSD is feasible, assists in appropriate patient selection and allows for extensive examination and planning. This may facilitate a focused and informed procedure and improve the potential for successful closure. (Figure Presented)

Sinus of Valsalva aneurysm is a rare cardiac malformation that stems from incomplete fusion of the aortic media and the aortic valve annulus, a weakness that may result in rupture of the sinus, large left-to-right shunt, and severe congestive heart failure. Historically, this lesion has been repaired surgically, but percutaneous closure (PC) has emerged as a therapeutic intervention over the last 20 years. We review and contrast 34 studies detailing the PC approach with 16 studies on surgical closure (SC), together comprising a total of 877 patients who were treated for ruptured sinus of Valsalva aneurysm from 1956 to 2014. Both groups had similar sites of rupture, age distribution, and clinical symptoms at presentation. Selection bias ultimately prohibits a direct comparison between the 2 groups as patients who underwent SC often had worse aortic regurgitation and more complex associated lesions, including endocarditis, bicuspid aortic valve, tunnel-type fistulous connections, larger defect size, and multiple site of rupture. In conclusion, although SC is indicated and reserved for these more complicated patients, our review of previously published reports reveals that PC in patients who are too ill to undergo bypass, with mild or no aortic regurgitation and simple associated defects (muscular ventricular septal defects, secundum atrial septal defect, small patent ductus arteriosus), can be safe, effective, and practical.

In this case report, we describe the use of the Aquadexâ„¢ system for ultrafiltration therapy in the pediatric cardiac intensive care setting in a patient with fluid overload and acute kidney injury after congenital heart surgery. The patient is an 11-year-old, 25 kg male with complex single ventricle anatomy who underwent a one and a half ventricle repair. The patient experienced multiple organ dysfunction syndrome including acute kidney injury in the early post-operative period secondary to low cardiac output syndrome and tachyarrhythmia. Ultrafiltration using the Aquadexâ„¢ system was utilized to treat fluid overload in the setting of acute kidney injury and hemodynamic instability. Negative fluid balance was safely achieved. It was subsequently possible to wean ventilatory and inotropic support. We conclude that the use of ultrafiltration therapy is feasible in hemodynamically unstable pediatric patients with significant fluid overload in the setting of acute kidney injury following congenital heart surgery.

A vascular ring (VR) is a rare congenital anomaly that has variable clinical presentation, but may cause trachea-esophageal compressive symptoms. We describe an infant with cystic fibrosis and subtle trachea-esophageal compressive symptoms which were initially attributed to other causes, delaying the diagnosis of a VR

Thoracic aortic disease is a known cause of aortic dilatation and poses significant risk of aortic dissection and rupture. Serial assessment of aortic root dimensions is traditionally performed using echocardiography, which is limited with older age and following surgery, due to poor acoustic windows. Although diastolic measurements are utilized as standard practice in decision making of adult aortopathy, systolic diameters are utilized in pediatric practice. Three-dimensional steady-state free precision (3D-SSFP) has shown promise as an alternate method for providing accurate and reproducible aortic measurements. The agreement between proximal aorta measurements by diastolic 3D-SSFP and echocardiography (both systole and diastole) was examined in 40 subjects. The maximum inner diameters at aortic annulus, root and sinotubular junction demonstrated excellent agreement between 3D-SSFP and echocardiography for all the 3 levels. The best agreement was observed for diastolic root dimensions with a mean difference of +0.01 cm, limits of agreement being -0.26 to +0.28 cm. Three D-SSFP can be used interchangeably with echocardiography in the serial assessment of the aortic root size. Careful attention to obtain an imaging plane utilizing 3D multiplanar reformatting is critical to maximize the agreement between the two imaging modalities.

BACKGROUND: Left atrial volume (LAV) increase is an indicator of diastolic dysfunction and a surrogate marker of significant left to right shunts. Normalization of LAV is currently performed by indexing to body surface area(1) (BSA(1)). The indexed LAV thus derived does not account for the nonlinear relationship of physiologic variables to BSA and has not been tested for independence to body size. Our objective was to identify a valid allometric model for indexing LAV and use it to develop Z-scores in children. METHODS AND RESULTS: LAV was measured in 300 normal subjects by echocardiography using the biplane area length method. LAV/BSA(1) had a residual relationship to BSA (r=0.52, P<0.0001). The allometric exponent (AE) derived for the entire cohort (1.27) using the least squares regression analysis also failed to eliminate the residual relationship to BSA (r=-0.15, P=0.01). Dividing the cohort in two groups with a BSA cut-off of 1 m(2) provided the best-fit allometric model. The AE for each group was 1.48 and 1.08 for BSA1 m(2), respectively, and was validated against an independent sample. The mean indexed LAV+/-SD for BSA1 m(2) is 31.5+/-5.5 mL and 26.0+/-4.2 mL, respectively, and was used to derive Z-scores. CONCLUSIONS: This study demonstrates the fallacy of using "per-BSA(1) standards" for normalization of LAV in pediatrics. LAV/BSA(1.48) for children with BSA1 m(2) is accurate and can be used to derive Z-scores.

BACKGROUND: Left ventricular (LV) end-diastolic volume (LVEDV) can be estimated by the formula (5/6) x area x length, or the "bullet" method. The aim of this study was to determine the range of normal LVEDV values in infants and young children (aged 0-3 years) by the subxiphoid bullet method. METHODS: Echocardiograms from 100 normal subjects aged