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Introduction: Single ventricle patients develop aortopulmonary collaterals (APC) whose flow (APCF) has been shown, in a cross-sectional study, to be inversely proportional to cerebral blood flow (CBF). Serial longitudinal CBF and APCF data in Fontan patients taking into account brain injury (BI) has never been reported. Decreased CBF may adversely impact neurodevelopmental outcome. Methods: A prospective longitudinal cohort of 27 Fontan patients (age 10 + 1.9 years, 74% male) underwent cardiac and brain MRIs 3-9 months after Fontan and 6.0 + 1.86 years afterwards to measure CBF, APCF and to assess BI (grouped into focal brain injury (FBI), generalized insult (GI) and hemorrhage). CBF was measured using jugular venous flow and APCF was measured by the difference between aortic flow and caval return. A multivariate linear regression model was used to assess the relationship between change in APCF and change in CBF controlling for time since Fontan, sex, and changes in BI. Results: Demographics, flow and BI data are shown in table 1. A strong inverse relationship was found between CBF and APCF when CBF was indexed to aortic flow and APCF was indexed to BSA (R^2 = 0.72, P+ 11% and APCF decreased by 0.73 + 0.67 l/min/m^2 (12% when indexed to aortic flow). CBF and APCF were significantly and inversely related when adjusting for time since Fontan, sex, and change in the visibility of BI on MRI. Each one unit increase in APCF was associated with an 8% decrease in CBF. Change in CBF was smaller for those with longer times since Fontan and was larger for males. Change in CBF was larger for those whose FBI or GI became less visible, but smaller for those whose hemorrhages became less visible. See table 2. Conclusion: CBF and APCF are inversely related across serial imaging, adjusting for time from Fontan, sex and BI. This may adversely impact neurodevelopment. As APCs can be embolized, this may be a modifiable risk factor. A large scale trial is warranted.

Introduction: Patients with malaligned common atrioventricular (AV) canal (CAVC) are difficult to manage when one ventricle is borderline hypoplastic. The decision between the single ventricle pathway or attempting a biventricular repair depends upon pre-operative parameters which have previously been studied only by echocardiography. The purpose of this study was to determine the utility of cardiac magnetic resonance (CMR) in predicting success of a biventricular repair in CAVC. Methods: We performed a single center, retrospective cohort study of children with varying degrees of CAVC malalignment who underwent CMR prior to definitive repair (7/1/10 to 2/28/21). The primary outcome was successful biventricular repair. CMR measurements were performed by the investigators. To account for both dominant right ventricles (RV) and left ventricles (LV), ratios of ventricular and AV valve size were normalized as differences from their expected values. Associations were tested using univariable logistic regression. Multivariable regression models using combinations of two variables with p-values less than 0.2 were tested. Results: We included 28 patients (median age at CMR: 5.2 months, 43% male). Clinical and CMR variables are shown in Table 1. The optimal multivariable predictive model included the normalized LV end diastolic volume (EDV) to total ventricular EDV ratio and the LV-RV angle in diastole. Area under the receiver operator characteristic curve was 0.83 (p = 0.041). An LV EDV to total EDV ratio between 0.30 and 0.66 had a sensitivity of 92% and specificity of 63% for predicting successful biventricular repair. Including an LV-RV angle in diastole of less than 72 degrees resulted in a sensitivity of 83% and specificity of 81%. Conclusions: Multiple CMR measures were associated with surgical outcomes. CMR measures such as LV EDV to total ventricular EDV ratio and LV-RV angle in diastole can accurately predict successful biventricular canal repair.

Objective: To estimate the association of rural vs urban living in the United States (US) with incident cognitive impairment (ICI), and to assess confounding, mediation, and effect heterogeneity by demographic, social, behavioral, and clinical risk factors. Methods: REGARDS is a cohort of 30,239 adults aged 45+ in the 48 contiguous states. We analyzed 20,592 participants who at baseline (2003-2007) were cognitively intact with no history of stroke and had cognition assessed an average of 7.1 years later. We used Rural-Urban Commuting Area (RUCA) codes to classify participants as urban (n = 16,436), large city/town (n = 2,420), or small/isolated rural (n = 1,736) at baseline. We defined ICI as falling ≥1.5 SD below the mean on at least two of three cognitive tests administered during follow-up: word list learning, word list delayed recall, and animal naming. Using urban as the referent, we estimated odds ratios of ICI for rural and for large city/town. Results: ICI occurred in 1,291 participants (6.3%). Rural residents had 49% higher odds of ICI adjusted for confounding by demographics (Model 2 in Table, OR = 1.49 [95% CI: 1.19, 1.85]). After further adjusting for potential mediators (Models 3-6), odds of ICI remained 25% higher for rural vs urban (Model 6, OR = 1.25 [0.99, 1.56]). In assessing effect heterogeneity, we found synergism of rural dwelling with black race, physical inactivity, and low self-rated health (all P < 0.1; see ORs in Table), but not for other ICI risk factors. We found no difference in ICI for large city/town vs urban (demographics-adjusted OR = 1.08 [0.88, 1.33]; fully adjusted OR = 0.95 [0.77, 1.18]), and no effect heterogeneity of ICI risk factors by large city/town (all P > 0.2). Conclusion: Rural living is an important social determinant of cognitive health in the US. ICI was significantly more frequent among rural dwellers than urban dwellers, partly due to confounding or mediation by ICI risk factors. Odds of ICI were highest for rural dwelling combined with black race, physical inactivity, or low self-rated health.

Background: Patients with a single ventricle experience a high rate of brain injury and adverse neurodevelopmental outcome; however, the incidence of brain abnormalities throughout surgical reconstruction and their relationship with cerebral blood flow, oxygen delivery, and carbon dioxide reactivity remain unknown. Methods: Patients with a single ventricle were studied with magnetic resonance imaging scans immediately prior to bidirectional Glenn (pre-BDG), before Fontan (BDG), and then 3 to 9 months after Fontan reconstruction. Results: One hundred sixty-eight consecutive subjects recruited into the project underwent 235 scans: 63 pre-BDG (mean age, 4.8±1.7 months), 118 BDG (2.9±1.4 years), and 54 after Fontan (2.4±1.0 years). Nonacute ischemic white matter changes on T2-weighted imaging, focal tissue loss, and ventriculomegaly were all more commonly detected in BDG and Fontan compared with pre-BDG patients ( P P Conclusions: Significant brain abnormalities are commonly present in patients with a single ventricle, and detection of these lesions increases as children progress through staged surgical reconstruction, with multiple coexisting lesions more common earlier than later. In addition, this study demonstrated that BDG patients had greater cerebral blood flow than did Fontan patients and that an inverse association exists of various indexes of cerebral blood flow with these brain lesions. However, CO 2 reactivity and oxygen delivery (with 1 exception) were not associated with brain lesion development. Clinical Trial Registration: URL: http://www.clinicaltrials.gov . Unique identifier: NCT02135081.

Introduction: Chronic postoperative pulmonary insufficiency (PPI) is the major cause of long-term morbidity and mortality in patients (pts) with tetralogy of Fallot (TOF). Pulmonary valve replacement (PVR) can mitigate the risk, but optimal timing for PVR remains controversial. Time-resolved 3D phase-contrast MRI (4DF) provides insight into complex intracardiac flow patterns. 4DF may help inform management decisions regarding timing of PVR. We describe the first quantitative serial 4DF analysis in an ovine model of PPI. Methods: A baseline cardiac MRI (CMRI) was performed on four Dorsett sheep (36-39kg) on a 3-Tesla Siemens scanner. Following baseline MRI, animals underwent pulmonary valvectomy and transannular patch (TAP) placement yielding PPI. Follow-up CMRI were obtained at 5mo and 7mo post-valvectomy (PoVa). Pathlines were emitted from a circular region of interest (ROI) representing the pulmonary valve annulus. Velocities, flow rate, and stresses were obtained throughout a complete cardiac cycle and compared across time. Results: Systolic max velocity, average velocity, and flow rate normal to the ROI plane decreased over time. Diastolic velocities increased at 5mo before decreasing at 7mo PoVa. Regurgitant flow was observed in diastole PoVa , and regurgitant flow rate increased with time. The max and average component of shear stress (viscosity = 3 cP) along the pulmonary artery wall decreased over time in systole. In diastole, shear stress increased at 5mo and decreased at 7mo. Parameters plotted in Figure 1. Conclusion: 4DF provides a new method for visualization and quantification of alterations in blood flow patterns in the right side of the heart in an ovine model of PPI. Alterations in above parameters may indicate myocardial and pulmonary vascular deterioration precedent to morphological changes. Characterization of altered flow patterns in human pts with TOF may help to ultimately inform decisions regarding timing of PVR.

Background: Anomalous aortic origin of a coronary artery (AAOCA) with an interarterial course is associated with sudden cardiac death in children. Objectives: Using cardiac MRI with adenosine, we evaluated coronary ostial stenosis, proximal coronary size, and left ventricular (LV) function in children with AAOCA. Methods: We prospectively enrolled children 5-18 years old with interarterial AAOCA. MRIs were reviewed for coronary artery origin, proximal course, dimensions, and cardiac function. Surgery consisted of the modified unroofing procedure. We used descriptive statistics and paired t-tests to evaluate for statistical significance. Results: Between 2/2009 and 5/2014, 24 subjects with AAOCA underwent 29 MRIs. The majority were male (N=19, 79%) with anomalous right coronary artery (AAORCA, N=20, 83%). Mean age was 12.8 years at time of initial MRI. MRI was performed an average of 7 months post-operatively in 8 subjects who underwent surgery. In all, the proximal anomalous coronary arose tangential to the aorta with an elliptical, slit-like ostium. The anomalous coronary measured smaller proximally (0.20 mm) compared to distally (0.31 mm, P=< 0.0001), and after surgical repair, the post-operative origin was significantly larger (0.36 vs. 0.21 mm, P=0.02). Other abnormalities at initial MRI included fixed inferior wall (N=1) and reversible subendocardial septal/inferior wall (N=1) perfusion defects. Post-operatively, the neo-ostium was round in 6 (see Figure), but in 2, the orifice remained elliptical. One patient had a new small mid-myocardial scar and one had dyskinetic septal wall motion. LV function was normal both before and after surgery (mean ejection fraction =68.1% vs. 67.5%, P=0.85). Conclusions: Cardiac MRI with adenosine is an important tool for the evaluation of anomalous anatomy, myocardial function, and ischemia/injury and should be considered for the initial and, when applicable, post-operative assessment of children with AAOCA.

A 4-year-old girl with Kabuki syndrome was evaluated and diagnosed with an atrial septal defect on the basis of an abnormal cardiac physical examination. A chest radiograph was performed, which demonstrated multiple skeletal abnormalities and mild prominence of the pulmonary vasculature consistent with an atrial septal defect (Figure 1). A complete echocardiogram was performed under sedation, which demonstrated the atrial septal defect as well as dual pulmonary arterial supply to the left lung with a partial anomalous left pulmonary artery (LPA) from the right pulmonary artery (RPA) (Figure 2). Cardiac magnetic resonance (MR) imaging was performed to further delineate pulmonary arterial anatomy as well as possible tracheal compression from the partial anomalous LPA. Figure 1. Chest radiograph in the anteroposterior projection demonstrates irregularity of the right clavicle with separation of the hypoplastic distal half (arrowhead), butterfly vertebrae of T11 (arrow), absence of the left twelfth rib (asterisk), mild prominence of the pulmonary vasculature, and a normal cardiac silhouette. Figure 2. High parasternal short-axis echocardiogram with color compare shows the partial anomalous LPA (ALPA) arising from the RPA. AAo indicates ascending aorta; MPA, main pulmonary artery; and DRPA, distal RPA. A complete cardiac MR study was performed including gadolinium-enhanced MR angiography. The 3-dimensional reconstructed MR angiography data set demonstrates that the left lung receives blood supply from 2 left pulmonary arteries. One of …

Introduction : Pulmonary insufficiency-induced right ventricular volume overload in adults with repaired tetralogy of Fallot (TOF) is associated with reduced exercise tolerance, ventricular arrhythmias and sudden cardiac death. Studies have shown that the severity of pulmonary insufficiency (PI) predicts these symptoms. There has been indirect evidence that pulmonary artery branch stenosis (PABS) exacerbates PI in adults with repaired TOF. However the impact of treatment of PABS on PI has not been evaluated. Hypothesis : Relief of unilateral PABS in the setting of PI alleviates the severity of PI. Methods : Newborn piglets (n=9) underwent pulmonary valve resection with transannular patch and left pulmonary artery (LPA) banding. Between 10 to 16 weeks later, a cardiac catheterization was performed with hemodynamic evaluation and stenting of the banded LPA. Immediately prior to catheterization, and then 1 week following intervention, a cardiac MRI was performed. MRI data obtained included main and branch pulmonary arterial forward and reverse flow, and right and left ventricular volume. Results: Six animals survived the protocol. At time of catheterization, the LPA had a discrete stenosis, with a mean gradient of 11.6 mmHg (range 9 –16.1) across the banded region. The mean diameter of the LPA at the banded region was 3.4 mm (range 3.1– 4.2) and 10.8 mm distally (range 9.6 –14) at baseline, compared with a mean right pulmonary artery diameter of 20.2 mm. The banded region was stented to a mean diameter of 10.4 mm (range 8 –12.6). The main pulmonary artery regurgitant fraction (RF) at baseline was a mean of 38.2%; after stenting of the LPA, the RF decreased to 29.6% (p=0.02). Flow into the LPA improved in all animals, from a mean of 12.2% of total at baseline to 33.6% following stenting (p Conclusions: In the setting of unilateral PABS, stenting alleviates the severity of PI in an animal model of repaired TOF. Though clinical studies are required, these findings should be considered in decisions regarding treatment of PABS after repair of TOF.