Comparison of Two Measurement Devices for Pulse Wave Velocity in Children: Which Tool Is Useful to Detect Vascular Alterations Caused by Overweight?

Diagnosing Arterial Stiffness in Pregnancy and Its Implications in the Cardio-Renal-Metabolic Chain

Cardio-renal and metabolic modifications during gestation are crucial determinants of foetal and maternal health in the short and long term. The cardio-renal metabolic syndrome is a vicious circle that starts in the presence of risk factors such as obesity, hypertension, diabetes, kidney disease and ageing, all predisposing to a status dominated by increased arterial stiffness and alteration of the vascular wall, which eventually damages the target organs, such as the heart and kidneys. The literature is scarce regarding cardio-renal metabolic syndrome in pregnancy cohorts. The present paper exposes the current state of the art and emphasises the most important findings of this entity, particularly in pregnant women. The early assessment of arterial function can lead to proper and individualised measures for women predisposed to hypertension, pre-eclampsia, eclampsia, and diabetes mellitus. This review focuses on available information regarding the assessment of arterial function during gestation, possible cut-off values, the possible predictive role for future events and modalities to reverse or control its dysfunction, a fact of crucial importance with excellent outcomes at meagre costs.

Arterial Stiffness and Left Ventricular Myocardial Function in Children with a Well-Functioning Bicuspid Aortic Valve

Fundamento:

A rigidez arterial é um importante preditor de aortopatia e remodelamento miocárdico em pacientes com válvula aórtica bicúspide, podendo estar aumentada na infância.

Objetivo:

Avaliar a rigidez arterial e a função miocárdica do ventrículo esquerdo em crianças com válvula aórtica bicúspide funcional.

Métodos:

Quarenta e quatro crianças com válvula aórtica bicúspide e 41 pares saudáveis com válvula aórtica tricúspide foram incluídos neste estudo caso-controle. Foram obtidos os diâmetros e os escores-z relacionados da raiz aórtica e da aorta ascendente. Quanto à função miocárdica do ventrículo esquerdo, juntamente com as velocidades de fluxo mitral e parâmetros do Modo M, as velocidades miocárdicas e os intervalos de tempo foram avaliados com Doppler tecidual. A análise da onda de pulso foi realizada por aparelho oscilométrico (Mobil-o-Graph). Um valor de p<0,05 foi considerado significativo.

Resultados:

O índice da massa ventricular esquerda, a velocidade A do fluxo mitral, o diâmetro e o escore z da aorta ascendente e o índice de desempenho miocárdico estavam significativamente maiores nos pacientes (p = 0,04, p = 0,02, p = 0,04, p <0,001 e p <0,001 respectivamente). O índice de desempenho miocárdico correlacionou-se positivamente com o diâmetro da aorta ascendente e a velocidade A (r=0,272; p=0,01, r=356; p=0,001, respectivamente). A análise multivariada revelou que o índice de desempenho miocárdico estava relacionado ao diâmetro da aorta ascendente (p = 0,01). O índice de aumento e a velocidade da onda de pulso foram semelhantes entre os grupos (p> 0,05).

Conclusão:

De acordo com a análise da onda de pulso oscilométrico, as crianças com válvula aórtica bicúspide funcional apresentam rigidez arterial semelhante a seus pares saudáveis. O diâmetro da aorta ascendente foi estabelecido como preditor independente da função miocárdica do ventrículo esquerdo. A rigidez arterial pode não ser um fator de risco grave em pacientes pediátricos sem dilatação acentuada da aorta ascendente.

Vascular Structure and Function in Children and Adolescents: What Impact Do Physical Activity, Health-Related Physical Fitness, and Exercise Have?

A physically active lifestyle can prevent cardiovascular disease. Exercise intervention studies in children and adolescents that aim to increase physical activity have resulted in reduced vascular wall thickening and improve cardiovascular function. Here we review the literature that explores the correlations between physical activity, health-related physical fitness, and exercise interventions with various measures of vascular structure and function in children and adolescents. While several of these studies identified improvements in vascular structure in response to physical activity, these associations were limited to studies that relied on questionnaires. Of concern, these findings were not replicated in studies featuring quantitative assessment of physical activity with accelerometers. Half of the studies reviewed reported improved vascular function with increased physical activity, with the type of vascular measurement and the way physical activity was assessed having an influence on the reported relationships. Similary, most of the studies identified in the literature report a beneficial association of health-related physical fitness with vascular structure and function. Overall, it was difficult to compare the results of these studies to one another as different methodologies were used to measure both, health-related physical fitness and vascular function. Likewise, exercise interventions may reduce both arterial wall thickness and increased vascular stiffness in pediatric populations at risk, but the impact clearly depends on the duration of the intervention and varies depending on the target groups. We identified only one study that examined vascular structure and function in young athletes, a group of particular interest with respect to understanding of cardiovascular adaptation to exercise. In conclusion, future studies will be needed that address the use of wall:diameter or wall:lumen-ratio as part of the evaluation of arterial wall thickness. Furthermore, it will be critical to introduce specific and quantitative measurements of physical activity, as intensity and duration of participation likely influence the effectiveness of exercise interventions.

Feasibility of Wave Intensity Analysis in Patients With Conotruncal Anomalies Before and After Pregnancy: New Physiological Insights?

Background: Conotruncal anomalies (CTA) are associated with ongoing dilation of the aortic root, as well as increased aortic stiffness, which may relate to intrinsic properties of the aorta. Pregnancy hormones lead to hemodynamic changes and remodeling of the tunica media, resulting in the opposite effect, i.e., increasing distensibility. These changes normalize post-pregnancy in healthy women but have not been fully investigated in CTA patients. Methods: We examined aortic distensibility and ventriculo-arterial coupling before and after pregnancy using cardiovascular magnetic resonance (CMR)-derived wave intensity analysis (WIA). Pre- and post-pregnancy CMR data were retrospectively analyzed. Aortic diameters were measured before, during, and after pregnancy by cardiac ultrasound and before and after pregnancy by CMR. Phase contrast MR flow sequences were used for calculating wave speed (c) and intensity (WI). A matched analysis was performed comparing results before and after pregnancy. Results: Thirteen women (n = 5, transposition of the great arteries; n = 6, tetralogy of Fallot; n = 1, double outlet right ventricle, n = 1, truncus arteriosus) had 19 pregnancies. Median time between delivery and second CMR was 2.3 years (range: 1-6 years). The aortic diameter increased significantly after pregnancy in nine (n = 9) patients by a median of 4 ± 2.3 mm (range: 2-7.0 mm, p = 0.01). There was no difference in c pre-/post-pregnancy (p = 0.73), suggesting that increased compliance, typically observed during pregnancy, does not persist long term. A significant inverse relationship was observed between c and heart rate (HR) after pregnancy (p = 0.01, r = 0.73). There was no significant difference in cardiac output, aortic/pulmonary regurgitation, or WI peaks pre-/post-pregnancy. Conclusions: WIA is feasible in this population and could provide physiological insights in larger cohorts. Aortic distensibility and wave intensity did not change before and after pregnancy in CTA patients, despite an increase in diameter, suggesting that pregnancy did not adversely affect coupling in the long-term.