The cardiovascular adaptations associated with structured exercise training in Fontan patients remain unknown. We hypothesised that short-term training causes cardiac remodelling and parallel improvement in maximal exercise capacity (VO2 max) in these patients.

Five patients, median age 19.5 (17.6–21.3) years, with a history of Fontan operation meeting inclusion/exclusion criteria, participated in a 3-month training programme designed to improve endurance. Magnetic resonance images for assessment of cardiac function, fibrosis, cardiac output, and liver elastography to assess stiffness were obtained at baseline and after training. Maximal exercise capacity (VO2 max) and cardiac output Qc (effective pulmonary blood flow) at rest and during exercise were measured (C2H2 rebreathing) at the same interval. VO2 max increased from median (IQR) 27.2 (26–28.7) to 29.6 (28.5–32.2) ml/min/kg (p = 0.04). There was an improvement in cardiac output (Qc) during maximal exercise testing from median (IQR) 10.3 (10.1–12.3) to 12.3 (10.9–14.9) l/min, but this change was variable (p = 0.14). Improvement in VO2 max correlated with an increase in ventricular mass (r = 0.95, p = 0.01), and improvement in Quality-of-life inventory (PedsQL) Cardiac scale scores for patient-reported symptoms (r = 0.90, p = 0.03) and cognitive problems (r = 0.89, p = 0.04). The correlation between VO2 max and Qc showed a positive trend but was not significant (r = 0.8, p = 0.08). No adverse cardiac or liver adaptations were noted.

Short-term training improved exercise capacity in this Fontan pilot without any adverse cardiac or liver adaptations. These results warrant further study in a larger population and over a longer duration of time.

NCT03263312, Unique Protocol ID: STU 122016-037; Registration Date: 18 January, 2017.

This study examined the relationship between patient performance on multiple memory measures and regional brain volumes using an FDA-cleared quantitative volumetric analysis program – Neuroreader™.

Ninety-two patients diagnosed with mild cognitive impairment (MCI) by a clinical neuropsychologist completed cognitive evaluations and underwent MR Neuroreader™ within 1 year of testing. Select brain regions were correlated with three widely used memory tests. Regression analyses were conducted to determine if using more than one memory measures would better predict hippocampal z-scores and to explore the added value of recognition memory to prediction models.

Memory performances were most strongly correlated with hippocampal volumes than other brain regions. After controlling for encoding/Immediate Recall standard scores, statistically significant correlations emerged between Delayed Recall and hippocampal volumes (rs ranging from .348 to .490). Regression analysis revealed that evaluating memory performance across multiple memory measures is a better predictor of hippocampal volume than individual memory performances. Recognition memory did not add further predictive utility to regression analyses.

This study provides support for use of MR Neuroreader™ hippocampal volumes as a clinically informative biomarker associated with memory performance, which is a critical diagnostic feature of MCI phenotype.

Differentiation of the so-called sinus venosus defect from other defects permitting shunting between the atrial chambers remains problematic. The lesion is not a true septal defect, and current theories to explain the existence of the sinus venosus defect fall short. The presence of persistent systemic to pulmonary venous connections has been proposed to explain the existence of the sinus venosus defect.

Clinical histories and radiological findings of six patients are reviewed. Three patients have veno-venous bridges, two have partial anomalous pulmonary venous connections, and one patient has a sinus venosus defect. The clinical information is reviewed, along with current developmental and morphological considerations.

We provide radiographic, developmental, and morphological evidence to support the theory that a so-called sinus venosus defect is the consequence of persistence of foetal systemic to pulmonary veno-venous bridges, rather than of deficiencies in atrial septation.