Left ventricular deformation and myocardial fibrosis in pediatric patients with Duchenne muscular dystrophy

Background: Left ventricular (LV) strain and rotation are emerging functional markers for early detection of LV dysfunction and have been associated with the burden of myocardial fibrosis in several disease states. This study examined the association between LV deformation (i.e., LV strain and rotation) and extent and location of LV myocardial fibrosis in pediatric patients with Duchenne muscular dystrophy (DMD). Methods and results: 34 pediatric patients with DMD underwent cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE) to assess LV myocardial fibrosis. Offline CMR feature-tracking analysis was used to assess global and segmental longitudinal and circumferential LV strain, and LV rotation. Patients with fibrosis (n = 18, 52.9%) were older than those without fibrosis (14 ± 3 years (yrs) vs 11 ± 2 yrs., p = 0.01). There was no significant difference in LV ejection fraction (LVEF) between subjects with and without fibrosis (54 ± 6% vs 56 ± 4%, p = 0.18). However, lower endocardial global circumferential strain (GCS), but not LV rotation, was associated with presence of fibrosis (adjusted Odds Ratio 1.25 [95% CI 1.01–1.56], p = 0.04). Both GCS and global longitudinal strain correlated with the extent of fibrosis (r =.52, p = 0.03 and r =.75, p &lt; 0.01, respectively). Importantly, segmental strain did not seem to correspond to location of fibrosis. Conclusion: A lower global, but not segmental, strain is associated with presence and extent of LV myocardial fibrosis in pediatric DMD patients. Therefore, strain parameters might detect structural myocardial alterations, however currently more research is needed to evaluate its value (e.g., prognostic) in clinical practice.</p

Thyroid dysfunction in pediatric Fontan patients is associated with unfavorable hemodynamic status and severity of protein-losing enteropathy: A report from the Fontan care network

Background: Thyroid dysfunction may have adverse effects on Fontan hemodynamics. Data on thyroid function in pediatric Fontan patients with or without protein-losing enteropathy (PLE) are limited. Methods: This retrospective multicenter study included 67 Fontan patients (median age 10.9 years; 35.8% female; 28.4% PLE) in whom thyroid function testing was performed. Results: Subclinical hypothyroidism (SHT) was present in 16 (23.9%) patients. Subjects with SHT had significantly lower systolic blood pressure (p = 0.014) and body weight z-score (p = 0.006), were in a worse New York Heart Association (NYHA) functional class (p = 0.004), were more often pacing dependent (p = 0.007), and were more likely to have PLE (p = 0.033, 8/19 (42.1%) patients). Serum thyroid stimulating hormone (TSH) levels were significantly higher in patients with NYHA class ≥ II (p = 0.005), significant atrioventricular valve regurgitation (p = 0.023), elevated serum natriuretic peptides (p = 0.031), and in those with PLE (p = 0.002). Patients with active PLE had significantly higher TSH levels than those in remission (p = 0.003). A strong inverse relationship was found between lower free triiodothyronine (fT3) levels and natriuretic peptides (r: −0.599, p = 0.040). Using binary logistic regression analysis we found that worse NYHA class was an independent predictor of SHT (OR 4.2; 95% CI 1.1–16.1, p = 0.036). Conclusions: Subclinical thyroid dysfunction is common in Fontan, particularly in patients with hemodynamic derangements and PLE. Future studies are needed to address the prognostic implications of thyroid dysfunction in the Fontan population

Comparability of different Z-score equations for aortic root dimensions in children with Marfan syndrome

BACKGROUND: Aortic root dilation is a major complication of Marfan syndrome and is one of the most important criteria in establishing the diagnosis. Currently, different echocardiographic nomograms are used to calculate aortic root Z-scores. The aim of the present study was to assess the potential differences in aortic root measurements when aortic root Z-scores were obtained in a cohort of paediatric Marfan patients using several published nomograms. METHODS: In a cohort of 100 children with Marfan syndrome, Z-scores for aortic root dimensions were calculated according to the nomograms of Pettersen et al, Gautier et al, Colan et al, and Lopez et al. Bland-Altman plots were used to estimate mean differences in Z-scores and to establish limits of agreement. RESULTS: The mean Z-score of the sinus of Valsalva for Lopez et al was significantly higher compared to Gautier et al (p < 0.01) and Pettersen et al (p = 0.03). The nomogram of Lopez et al resulted in substantially higher Z-scores in patients with a large sinus of Valsalva diameter. Thirty-five percentage of the studied patients would have a Z-score ≥ 2 using Lopez et al compared to 20% for Pettersen et al, 21% for Gautier et al, and 33% for Colan et al. CONCLUSION: The currently available nomograms for calculating Z-scores of aortic dilation in children with Marfan syndrome lead to clinically relevant differences in Z-scores, especially in children with a relative large aortic root diameter. This could have impact on both the diagnosis and treatment of patients with Marfan syndrome

Fontan Circulation Associated Organ Abnormalities Beyond the Heart, Lungs, Liver, and Gut: A Systematic Review

Introduction: Patients with a Fontan circulation are at risk for sequelae of Fontan physiology during follow-up. Fontan physiology affects all organ systems and an overview of end-organ damage is needed. Methods: We performed a systematic review of abnormalities in multiple organ systems for patients with a longstanding Fontan circulation. We searched online databases for articles describing abnormalities in multiple organ systems. Cardio-pulmonary abnormalities, protein losing enteropathy, and Fontan associated liver disease have already extensively been described and were excluded from this systematic review. Results: Our search returned 5,704 unique articles. After screening, we found 111 articles relating to multiple organ systems. We found abnormalities in, among others, the nervous system, pituitary, kidneys, and musculoskeletal system. Pituitary edema—relating to the unique pituitary vasculature- may affect the thyroid axis. Renal dysfunction is common. Creatinine based renal function estimates may be inappropriate due to myopenia. Both lean muscle mass and bone mineral density are decreased. These abnormalities in multiple organ systems may be related to Fontan physiology, cyanosis, iatrogenic factors, or lifestyle. Conclusions: Health care providers should be vigilant for hypothyroidism, visual or hearing deficits, and sleep disordered breathing in Fontan patients. We recommend including cystatin C for assessment of renal function. This review may aid health care providers and guide future research. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021232461, PROSPERO, identifier: CRD42021232461