Physiological and clinical consequences of relief of right ventricular outflow tract obstruction late after repair of congenital heart defects.

BACKGROUND: Right ventricular outflow tract obstruction (RVOTO) is a common problem after repair of congenital heart disease. Percutaneous pulmonary valve implantation (PPVI) can treat this condition without consequent pulmonary regurgitation or cardiopulmonary bypass. Our aim was to investigate the clinical and physiological response to relieving RVOTO. METHODS AND RESULTS: We studied 18 patients who underwent PPVI for RVOTO (72% male, median age 20 years) from a total of 93 who had this procedure for various indications. All had a right ventricular outflow tract (RVOT) gradient >50 mm Hg on echocardiography without important pulmonary regurgitation (less than mild or regurgitant fraction <10% on magnetic resonance imaging [MRI]). Cardiopulmonary exercise testing, tissue Doppler echocardiography, and MRI were performed before and within 50 days of PPVI. PPVI reduced RVOT gradient (51.4 to 21.7 mm Hg, P<0.001) and right ventricular systolic pressure (72.8 to 47.3 mm Hg, P<0.001) at catheterization. Symptoms and aerobic (25.7 to 28.9 mL.kg(-1).min(-1), P=0.002) and anaerobic (14.4 to 16.2 mL.kg(-1).min(-1), P=0.002) exercise capacity improved. Myocardial systolic velocity improved acutely (tricuspid 4.8 to 5.3 cm/s, P=0.05; mitral 4.7 to 5.5 cm/s, P=0.01), whereas isovolumic acceleration was unchanged. The tricuspid annular velocity was not maintained on intermediate follow-up. Right ventricular end-diastolic volume (99.9 to 89.7 mL/m2, P<0.001) fell, whereas effective stroke volume (43.7 to 48.3 mL/m2, P=0.06) and ejection fraction (48.0% to 56.8%, P=0.01) increased. Left ventricular end-diastolic volume (72.5 to 77.4 mL/m2, P=0.145), stroke volume (45.3 to 50.6 mL/m2, P=0.02), and ejection fraction (62.6% to 65.8%, P=0.03) increased. CONCLUSIONS: PPVI relieves RVOTO, which leads to an early improvement in biventricular performance. Furthermore, it reduces symptoms and improves exercise tolerance. These findings have important implications for the management of this increasingly common condition

Heart rate recovery in patients with hypertrophic cardiomyopathy

Recovery in heart rate (HR) after exercise is a measure of autonomic function and a prognostic indicator in cardiovascular disease. The aim of this study was to characterize heart rate recovery (HRR) and to determine its relation to cardiac function and morphology in patients with hypertrophic cardiomyopathy (HC). We studied 18 healthy volunteers and 41 individuals with HC. All patients underwent clinical assessment and transthoracic echocardiography. Continuous beat-by-beat assessment of HR was obtained during and after cardiopulmonary exercise testing using finger plethysmography. HRR and power spectral densities were calculated on 3 minutes of continuous RR recordings. Absolute HRR was lower in patients than that in controls at 1, 2, and 3 minutes (25.7 ± 8.4 vs 35.3 ± 11.0 beats/min, p <0.001; 36.8 ± 9.4 vs 53.6 ± 13.2 beats/min, p <0.001; 41.2 ± 12.2 vs 62.1 ± 14.5 beats/min, p <0.001, respectively). HRR remained lower in patients at 2 and 3 minutes after normalization to peak HR. After normalization to the difference in HR between peak exercise and rest, HRR was significantly impaired in individuals with obstructive HC at 3 minutes compared with controls. HR at 3 minutes correlated with peak left ventricular outflow tract gradient (B 0.154 beats/min/mm Hg, confidence interval 0.010 to 0.299, p = 0.037) and remained a significant predictor of HRR after multivariable analysis. Spectral analysis showed a trend toward an increased low-frequency to high-frequency ratio in patients (p = 0.08) suggesting sympathetic predominance. In conclusion, HRR is impaired in HC and correlates with the severity of left ventricular outflow tract gradient. Prospective studies of the prognostic implications of impaired HRR in HC are warranted. © 2014 Elsevier Inc. All rights reserved

A Community-Based Intervention to Prevent Obesity Beginning at Birth among American Indian Children: Study Design and Rationale for the PTOTS study

Eating and physical activity behaviors associated with adult obesity have early antecedents, yet few studies have focused on obesity prevention interventions targeting very young children. Efforts to prevent obesity beginning at birth seem particularly important in populations at risk for early-onset obesity. National estimates indicate that American Indian (AI) children have higher rates of overweight and obesity than children of other races/ethnicities. The Prevention of Toddler Obesity and Teeth Health Study (PTOTS) is a community-partnered randomized controlled trial designed to prevent obesity beginning at birth in AI children. PTOTS was developed to test the effectiveness of a multi-component intervention designed to: promote breastfeeding, reduce sugar-sweetened beverage consumption, appropriately time the introduction of healthy solid foods, and counsel parents to reduce sedentary lifestyles in their children. A birth cohort of 577 children from five AI tribes is randomized by tribe to either the intervention (three tribes) or the comparison condition (two tribes). The strengths and weaknesses of PTOTS include a focus on a critical growth phase, placement in the community, and intervention at many levels, using a variety of approaches

'In the wake of a pandemic': dietary patterns and impact on child health after COVID-19

INTRODUCTION Our companion Report: ‘Emerging Dietary Patterns: Impact on Child Health’ discussed ways in which traditional dietary patterns in both the UK and internationally were changing. In concluding we argued that: ‘The interconnected nature of food, climate and health is the biggest challenge we face, but therein also lies its strength and boundless potential should we act with the necessary urgency, creativity and commitment. It is at the local level – supported by national policy – that the largest returns from such pro-activity will accrue.’ We continued: ‘The food that we eat here and now can change the world.’ adding: ‘If we are serious about protecting and restoring natural environments, safeguarding the health and wellbeing of our children today and restoring and protecting that of future generations, then there is only one solution. We must change it.’ Then came Covid-19 and change was imposed – with the arrival and experience of a pandemic. The full outcome of Covid-19; its effects and repercussions not just for the present generations but for the many that will succeed it cannot be estimated now. In the 102 years since Spanish ‘flu devastated an older world order, we are still learning its lessons today. But what has become immediately apparent is that what we eat and how we eat has undergone a revolution in four short months. 6 ‘Coronavirus pandemic will change the food industry and eating habits forever, says CEO of Food and Drink Federation, Ian Wright.’ ([email protected] 7 April 2020) ‘To prevent the next pandemic we must take on factory farming.’ (Jonathan Safran Foer and Aaron Gross, The Guardian, 21 April 2020.) ‘Covid-19 will definitely be an accelerator on the conscious consumer patterns that we see unfolding. As the consumer gets more conscious, we also see more interest in sustainable, locally produced food systems solutions.’ (David Brandes, Food Navigator, 17 April 2020.) ‘The virus is a warning that Britain’s food system must change,’ (‘The Guardian,’ 18th April 2020). It would also be unjust to address the Covid-19 pandemic in isolation without highlighting its interactions with another global force to become manifest in the same era in response to an incident in the US; namely, the police killing of George Floyd and the Black Lives Matter Movement. Pandemics, poor health, systemic inequalities and a lack of environmental protections harm black, ethnic minority and disadvantaged communities in all countries more than any other groups, and the two events have shed a harsh light on those realities and their frightening interconnections – such as the higher death rate in BAME communities including healthcare workers on the frontline (Public Health England, June 2020, ‘Beyond the data: Understanding the impact of COVID-19 on BAME groups’): https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/892376/COVID_stakeholder_engagement_synthesis_beyond_the_data.pdf Therefore, to address fall-out from the pandemic without considering these marginalised groups would be inappropriate; to address the environmental crisis without considering its impact on such groups would be pointless and the separation of civil rights from health and environmental policy is delusional. The silos in which policy-making still exists in these fields are stubborn obstacles to change. Both within and without the UK’s boundaries, the diverse spectrum of peoples requires a similar diversity and inclusion in the systems that sustain life – and the production of the food that is eaten in order to live. Sometimes change is immediate and imposed rather than incremental and the pandemic has seen an abrupt conclusion to familiar and traditional ways of living. As we offer our thoughts about the many ways in which Covid-19 has changed our dietary patterns, we must remember that the ‘brave new world’ of our future ambition ‘has such people in it’, (‘The Tempest’, William Shakespeare). Those who would construct better dietary patterns in the wake of this pandemic must ensure that people rather than systems prevail…

A Community-Based Intervention to Prevent Obesity Beginning at Birth among American Indian Children: Study Design and Rationale for the PTOTS study

Eating and physical activity behaviors associated with adult obesity have early antecedents, yet few studies have focused on obesity prevention interventions targeting very young children. Efforts to prevent obesity beginning at birth seem particularly important in populations at risk for early-onset obesity. National estimates indicate that American Indian (AI) children have higher rates of overweight and obesity than children of other races/ethnicities. The Prevention of Toddler Obesity and Teeth Health Study (PTOTS) is a community-partnered randomized controlled trial designed to prevent obesity beginning at birth in AI children. PTOTS was developed to test the effectiveness of a multi-component intervention designed to: promote breastfeeding, reduce sugar-sweetened beverage consumption, appropriately time the introduction of healthy solid foods, and counsel parents to reduce sedentary lifestyles in their children. A birth cohort of 577 children from five AI tribes is randomized by tribe to either the intervention (three tribes) or the comparison condition (two tribes). The strengths and weaknesses of PTOTS include a focus on a critical growth phase, placement in the community, and intervention at many levels, using a variety of approaches