RESUMEN
Aortic valve surgery is the definitive treatment for aortic stenosis (AS). No specific recommendation is available on how exercise training should be conducted and evaluated after aortic valve replacement (AVR). This study aimed to examine the effect of aerobic exercise training on exercise capacity following AVR. In addition to our primary outcome variable, peak oxygen uptake (peakVO2 ), the effect on submaximal cardiopulmonary variables including oxygen uptake kinetics (tau), oxygen uptake efficiency slope (OUES) and ventilatory efficiency (VE/VCO2 slope) was evaluated. Following AVR due to AS, 12 patients were randomized to either a group receiving 12 weeks of supervised aerobic exercise training (EX) or a control group (CON). Exercise capacity was assessed by a maximal cardiopulmonary exercise test (CPET). There was a significant increase in peak load (+28%, P = 0·031) and in peakVO2 (+23%, P = 0·031) in EX, corresponding to an increase in achieved percentage of predicted peakVO2 from 88 to 104% (P = 0·031). For submaximal variables, there were only non-statistically significant trends in improvement between CPETs in EX. In CON, there were no significant differences in any maximal or submaximal variable between CPETs. We conclude that 12 weeks of supervised aerobic exercise training induces significant adaptations in cardiopulmonary function following AVR, especially in regard to maximal variables including peakVO2 . In addition, we provide novel data on the effect on several submaximal variables following exercise training in this group of patients.
Asunto(s)
Estenosis de la Válvula Aórtica/cirugía , Válvula Aórtica/cirugía , Rehabilitación Cardiaca/métodos , Capacidad Cardiovascular , Prueba de Esfuerzo , Terapia por Ejercicio/métodos , Implantación de Prótesis de Válvulas Cardíacas , Adulto , Anciano , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/fisiopatología , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/fisiopatología , Rehabilitación Cardiaca/efectos adversos , Terapia por Ejercicio/efectos adversos , Tolerancia al Ejercicio , Femenino , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Consumo de Oxígeno , Valor Predictivo de las Pruebas , Recuperación de la Función , Suecia , Factores de Tiempo , Resultado del TratamientoRESUMEN
Air pollution is responsible for one in eight premature deaths worldwide, and thereby a major threat to human health. Health impact assessments of hypothetic changes in air pollution concentrations can be used as a mean of assessing the health impacts of policy, plans and projects, and support decision-makers in choices to prevent disease. The aim of this study was to estimate health impacts attributable to a hypothetical decrease in air pollution concentrations in the city of Malmö in Southern Sweden corresponding to a policy on-road transportations without tail-pipe emissions in the municipality. We used air pollution data modelled for each of the 326,092 inhabitants in Malmö by a Gaussian dispersion model combined with an emission database with >40,000 sources. The dispersion model calculates Nitrogen Oxides (NOx) (later transformed into Nitrogen Dioxide (NO2)) and particulate matter with an aerodynamic diameterâ¯<â¯2.5⯵g/m3 (PM2.5) with high spatial and temporal resolution (85â¯m and 1â¯h, respectively). The average individual reduction was 5.1 (ranging from 0.6 to 11.8) µg/m3 in NO2, which would prevent 55 (2% of all deaths) to 93 (4%) deaths annually, depending on dose-response function used. Furthermore, we estimate that the NO2 reduction would result in 21 (6%) fewer cases of incident asthma in children, 95 (10%) fewer children with bronchitis every year, 30 (1%) fewer hospital admissions for respiratory disease, 87(4%) fewer dementia cases, and 11(11%) fewer cases of preeclampsia every year. The average reduction in PM2.5 of 0.6 (ranging from 0.1 till 1.7) µg/m3 would mean that 2729 (0.3%) work days would not be lost due to sick-days and that there would be 16,472 fewer restricted activity days (0.3%) that year had all on-road transportations been without tail-pipe emissions. Even though the estimates are sensitive to the dose-response functions used and to exposure misclassification errors, even the most conservative estimate of the number of prevented deaths is 7 times larger than the annual traffic fatalities in Malmö, indicating a substantial possibility to reduce the health burden attributed to tail-pipe emissions in the study area.