Biatrial Remodeling in Patients with Cystic Fibrosis Running Title: Atrial Function in Cystic Fibrosis

Proinflammatory indicators and the relevance of echocardiography in children with cystic fibrosis

As the life expectancy improves in cystic fibrosis, cardiac dysfunction is becoming an important risk factor for morbidity and mortality. Here, the association of cardiac dysfunction with proinflammatory markers and neurohormones between cystic fibrosis patients and healthy children was investigated. Echocardiographic measurements of right and left ventricular morphology and functions together with levels of proinflammatory markers and neurohormones (renin, angiotensin-II, and aldosterone) were obtained and analysed in a study group of 21 cystic fibrosis children aged 5-18 years and compared with age- and gender-matched healthy children. It was shown that patients had significantly higher interleukin-6, C-reactive protein, renin and aldosterone levels (p < 0.05), dilated right ventricles, decreased left ventricle sizes, as well as both right and left ventricular dysfunction. These echocardiographic changes correlated with hypoxia, interleukin-1 α, interleukin-6, C-reactive protein, and aldosterone (p < 0.05) levels. The current study revealed that hypoxia, proinflammatory markers, and neurohormones are major determinants of subclinical changes in ventricular morphology and function. While the right ventricle anatomy was affected by cardiac remodeling, the left ventricle changes were induced by right ventricle dilation and hypoxia. A significant but subclinical systolic and diastolic right ventricle dysfunction in our patients was associated with hypoxia and inflammatory markers. Systolic left ventricle function was affected by hypoxia and neurohormones. Echocardiography is a reliable and non-invasive method that is used safely in cystic fibrosis children for screening and detection of cardiac anatomical and functional changes. Extensive studies are needed to determine the time and frequency of screening and treatment suggestions for such changes.

Effects of a Long-Term Wearable Activity Tracker-Based Exercise Intervention on Cardiac Morphology and Function of Patients with Cystic Fibrosis

Several studies have shown that patients with cystic fibrosis (CF), even at a young age, have pulmonary and cardiac abnormalities. The main complications are cardiac right ventricular (RV) systolic and/or diastolic dysfunction and pulmonary hypertension, which affects their prognosis. Exercise training (ET) is recommended in patients with CF as a therapeutic modality to improve physical fitness and health-related quality of life. However, questions remain regarding its optimal effective and safe dose and its effects on the patients’ cardiac function. The study aimed to provide a wearable activity tracker (WAT)-based ET to promote physical activity in CF patients and assess its effects on cardiac morphology and function. Forty-two stable CF individuals (aged 16.8 ± 3.6 years) were randomly assigned to either the intervention (Group A) or the control group (Group B). Group A participated in a 1-year WAT-based ET program three times per week. All patients underwent a 6-min walking test (6-MWT) and an echocardiographic assessment focused mainly on RV anatomy and function at the baseline and the end of the study. RV systolic function was evaluated by measuring the tricuspid annular plane systolic excursion (TAPSE), the systolic tricuspid annular velocity (TVS’), the RV free-wall longitudinal strain (RVFWSL), and the right ventricular four-chamber longitudinal strain (RV4CSL). RV diastolic function was assessed using early (TVE) and late (TVA) diastolic transtricuspid flow velocity and their ratio TVE/A. Pulmonary artery systolic pressure (PASP) was also estimated. In Group A after ET, the 6MWT distance improved by 20.6% (p < 0.05), TVA decreased by 17% (p < 0.05), and TVE/A increased by 13.2% (p < 0.05). Moreover, TAPSE, TVS’, RVFWSL, and RV4CSL increased by 8.3% (p < 0.05), 9.0% (p < 0.05), 13.7% (p < 0.05), and 26.7% (p < 0.05), respectively, while PASP decreased by 7.6% (p < 0.05). At the end of the study, there was a significant linear correlation between the number of steps and the PASP (r = −0.727, p < 0.01) as well as the indices of RV systolic function in Group A. In conclusion, WAT is a valuable tool for implementing an effective ET program in CF. Furthermore, ET has a positive effect on RV systolic and diastolic function.

Incorporating Risk Stratification Into the Practice of Pediatric Preventive Cardiology

Atherosclerosis in its earliest stages is associated with the same traditional cardiovascular disease (CVD) risk factors as are associated with manifest CVD events in adulthood. Clustering of risk factors is associated with exponential increases in atherosclerotic burden from a young age. Some medical conditions and risk behaviours occurring in children can either increase the likelihood of higher levels of risk factors (such as chronic kidney disease) or the presence of risk factor clustering (such as obesity and cardiometabolic syndrome) or are associated with acquired coronary artery pathology (such as Kawasaki disease). This creates a milieu for-or increases the impact of-accelerated atherosclerosis that, in turn, increases the likelihood of premature CVD. This review highlights the importance of considering the total risk factor and risk-condition profile of pediatric patients. An algorithm is provided for stratifying patients into high-, moderate-, and at-risk categories, and practical examples are provided as to how the evaluation and management of 1 risk factor or risk condition might need to be intensified in the context of additional risk factors or risk conditions. For example, for treatment of an adolescent with familial hypercholesterolemia, the target low-density lipoprotein cholesterol level might be lowered by the concomitant presence of low high-density lipoprotein cholesterol or elevated lipoprotein(a) levels. As awareness of cardiovascular risk and atherosclerosis in pediatric patients increases, new at-risk conditions that warrant consideration are emerging. The identification and management of high-risk individuals is an important part of the overall practice of pediatric preventive cardiology.