Impact of left atrial volume, sphericity, and fibrosis on the outcome of catheter ablation for atrial fibrillation.

INTRODUCTION: To investigate the relation between left atrial (LA) volume, sphericity, and fibrotic content derived from contrast-enhanced cardiac magnetic resonance imaging (CE-CMR) and their impact on the outcome of catheter ablation for atrial fibrillation (AF). METHODS AND RESULTS: In 83 patients undergoing catheter ablation for AF, CE-CMR was used to assess LA volume, sphericity, and fibrosis. There was a significant correlation between LA volume and sphericity (R  =  0.535, P < 0.001) and between LA volume and fibrosis (R  =  0.241, P  =  0.029). Multivariate analyses demonstrated that LA volume was the strongest independent predictor of AF recurrence after catheter ablation (1.019, P  =  0.018). CONCLUSION: LA volume, sphericity, and fibrosis were closely related; however, LA volume was the strongest predictor of AF recurrence after catheter ablation.

Left atrial fibrosis quantification by late gadolinium-enhanced magnetic resonance: a new method to standardize the thresholds for reproducibility.

AIMS: Identification of left atrial (LA) fibrosis through late gadolinium-enhanced cardiac magnetic resonance (LGE-CMR) remains controversial due to the heterogeneity and lack of reproducibility of proposed methods. Our aim is to describe a normalized, reproducible, standardized method to evaluate LA fibrosis through LGE-CMR. METHODS AND RESULTS: Electrocardiogram- and respiratory-gated 3-Tesla LGE-CMR was performed in 10 healthy young volunteers and 30 patients with atrial fibrillation (AF): 10 with paroxysmal AF, 10 with persistent AF, and 10 with a previous AF ablation procedure. Local image intensity ratio (IIR) of the LA was calculated as the absolute pixel intensity to mean blood pool intensity ratio. The healthy atrial tissue threshold was defined in young healthy volunteers (upper limit of normality set at IIR tissue mean plus 2 SDs). Dense atrial scarring was characterized in patients with previous radiofrequency-induced scarring (post-AF ablation patients). Validation groups consisted of patients with paroxysmal and persistent AFs. The upper limit of normal IIR was 1.20; IIR values higher than 1.32 (60% of mean maximum pixel intensity in post-ablation patients) were considered dense scar. Image intensity ratio values between 1.2 and 1.32 identified interstitial fibrosis. Patients with paroxysmal and persistent AFs had less atrial fibrotic tissue compared with post-ablation patients. Endocardial bipolar voltage was correlated to IIR values. CONCLUSIONS: An IIR of 1.2 identifies the upper limit of normality in healthy young individuals. An IIR of >1.32 defines dense atrial fibrosis in post-ablation patients. Our results provide a consistent, comparable, and normalized tool to assess atrial arrhythmogenic substrate.

The views of children in residential care on the COVID-19 lockdown: Implications for and their well-being and psychosocial intervention.

BACKGROUND: Recent international research has warned of the impact of the COVID-19 lockdown on vulnerable children. However, little is known regarding the in-care population. OBJECTIVE: To find out how children in residential care perceived the influence of the COVID-19 lockdown in their everyday life, relationships and subjective well-being. PARTICIPANTS AND SETTING: 856 children from 10 to 17 years old (Mage = 15.5, males = 71.2%, females = 28.8%) living in residential centres in Catalonia. METHODS: Cross-sectional study. Children responded to an on-line questionnaire administered between June and July 2020. Bivariate analysis and multiple linear regression were used comparing the answers by sex. RESULTS: Better relationships with caregivers (ß = 9.156, [4.089-14.22], r2 = 0.244, p < .01) and having a person of trust (ß = 4.588, [2.041-7.134], r2 = 0.244, p < .01) were found to be relevant for children's subjective well-being. For girls, improving their grades (ß = 14.86, [8.560-21.15], r2 = 0.234, p < .01) were relevant while boys' subjective well-being was significantly affected by an increase in use of social networks (ß = 8.917, [2.733-15.10], r2 = 0.234, p < .01). CONCLUSIONS: A gender perspective is needed to help girls in situations of vulnerability. We should continue to listen to children's opinions, giving them the opportunity to participate in improving the children's home and its immediate environment and ensuring they have access to stable adult role models.