Altered Central Hemodynamics in Individuals with Down Syndrome
Background: Individuals with Down Syndrome (DS) have autonomic dysfunction impacting regulation of heart rate, Blood Pressure (BP), and peripheral vasoconstriction. This may alter central hemodynamics through different wave reflections. We investigated central hemodynamics including wave reflection...
| Main Authors: | , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
BMC
2019-12-01
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| Series: | Artery Research |
| Subjects: | |
| Online Access: | https://www.atlantis-press.com/article/125928186/view |
| _version_ | 1818543417883361280 |
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| author | Thessa Irena Maria Hilgenkamp Elizabeth Cornellia Schroeder Sang Ouk Wee Georgios Grigoriadis Alexander Jacob Rosenberg Tracy Baynard Bo Fernhall |
| author_facet | Thessa Irena Maria Hilgenkamp Elizabeth Cornellia Schroeder Sang Ouk Wee Georgios Grigoriadis Alexander Jacob Rosenberg Tracy Baynard Bo Fernhall |
| author_sort | Thessa Irena Maria Hilgenkamp |
| collection | DOAJ |
| description | Background: Individuals with Down Syndrome (DS) have autonomic dysfunction impacting regulation of heart rate, Blood Pressure (BP), and peripheral vasoconstriction. This may alter central hemodynamics through different wave reflections. We investigated central hemodynamics including wave reflection during rest and a sympathoexcitatory stimulus [Lower Body Negative Pressure (LBNP)] in individuals with DS and controls.
Methods: Radial applanation tonometry was performed on participants with and without DS before and during 5-min LBNP stimulus of −20 mmHg. Waveforms were calibrated to mean and diastolic BP. Generalized transfer function was used to estimate aortic pressures [Systolic Blood Pressure (aSBP), Diastolic Blood Pressure (aDBP), mean pressure (aMAP), pulse pressure (aPP)], Augmentation Index (AIx), augmentation index normalized for HR (AIx@75), Augmentation Pressure (AP), Reflection Index (RIx), Time to Reflection (Tr), forward and reflected wave magnitude (Pf and Pb).
Results: Fifteen individuals with DS (male n = 12, age 24 ± 4 years, BMI 28 ± 5 kg/m2) and 16 control participants (male n = 12, age 24 ± 4 years, BMI 25 ± 5 kg/m2) participated. Baseline differences showed greater AP, higher AIx and AIx@75, a greater RIx, shorter Tr and larger Pb in individuals with DS (p < 0.05). In response to LBNP, interaction effects were observed for AIx, AIx@75, AP, RIx and Pb, due to reductions in the outcomes in response to LBNP for individuals with DS with no change in the controls.
Conclusion: These results show that central hemodynamics and wave reflections are different in individuals with DS at rest and in response to LBNP, probably as a result of anatomical differences and reduced peripheral vasoconstrictive control during LBNP.
HIGHLIGHTS
•Individuals with DS exhibit greater central hemodynamic load at rest.
•Individuals with DS have greater indices of wave reflections at rest.
•Individuals with DS maintained blood pressure during LBNP with reduced wave reflection. |
| first_indexed | 2024-12-11T22:35:07Z |
| format | Article |
| id | doaj.art-007fde2a34b74e54b3844759bf46969e |
| institution | Directory Open Access Journal |
| issn | 1876-4401 |
| language | English |
| last_indexed | 2024-12-11T22:35:07Z |
| publishDate | 2019-12-01 |
| publisher | BMC |
| record_format | Article |
| series | Artery Research |
| spelling | doaj.art-007fde2a34b74e54b3844759bf46969e2022-12-22T00:48:00ZengBMCArtery Research1876-44012019-12-0125310.2991/artres.k.191204.001Altered Central Hemodynamics in Individuals with Down SyndromeThessa Irena Maria HilgenkampElizabeth Cornellia SchroederSang Ouk WeeGeorgios GrigoriadisAlexander Jacob RosenbergTracy BaynardBo FernhallBackground: Individuals with Down Syndrome (DS) have autonomic dysfunction impacting regulation of heart rate, Blood Pressure (BP), and peripheral vasoconstriction. This may alter central hemodynamics through different wave reflections. We investigated central hemodynamics including wave reflection during rest and a sympathoexcitatory stimulus [Lower Body Negative Pressure (LBNP)] in individuals with DS and controls. Methods: Radial applanation tonometry was performed on participants with and without DS before and during 5-min LBNP stimulus of −20 mmHg. Waveforms were calibrated to mean and diastolic BP. Generalized transfer function was used to estimate aortic pressures [Systolic Blood Pressure (aSBP), Diastolic Blood Pressure (aDBP), mean pressure (aMAP), pulse pressure (aPP)], Augmentation Index (AIx), augmentation index normalized for HR (AIx@75), Augmentation Pressure (AP), Reflection Index (RIx), Time to Reflection (Tr), forward and reflected wave magnitude (Pf and Pb). Results: Fifteen individuals with DS (male n = 12, age 24 ± 4 years, BMI 28 ± 5 kg/m2) and 16 control participants (male n = 12, age 24 ± 4 years, BMI 25 ± 5 kg/m2) participated. Baseline differences showed greater AP, higher AIx and AIx@75, a greater RIx, shorter Tr and larger Pb in individuals with DS (p < 0.05). In response to LBNP, interaction effects were observed for AIx, AIx@75, AP, RIx and Pb, due to reductions in the outcomes in response to LBNP for individuals with DS with no change in the controls. Conclusion: These results show that central hemodynamics and wave reflections are different in individuals with DS at rest and in response to LBNP, probably as a result of anatomical differences and reduced peripheral vasoconstrictive control during LBNP. HIGHLIGHTS •Individuals with DS exhibit greater central hemodynamic load at rest. •Individuals with DS have greater indices of wave reflections at rest. •Individuals with DS maintained blood pressure during LBNP with reduced wave reflection.https://www.atlantis-press.com/article/125928186/viewDown syndromevascular functionsympathetic stimulusautonomic nervous system |
| spellingShingle | Thessa Irena Maria Hilgenkamp Elizabeth Cornellia Schroeder Sang Ouk Wee Georgios Grigoriadis Alexander Jacob Rosenberg Tracy Baynard Bo Fernhall Altered Central Hemodynamics in Individuals with Down Syndrome Artery Research Down syndrome vascular function sympathetic stimulus autonomic nervous system |
| title | Altered Central Hemodynamics in Individuals with Down Syndrome |
| title_full | Altered Central Hemodynamics in Individuals with Down Syndrome |
| title_fullStr | Altered Central Hemodynamics in Individuals with Down Syndrome |
| title_full_unstemmed | Altered Central Hemodynamics in Individuals with Down Syndrome |
| title_short | Altered Central Hemodynamics in Individuals with Down Syndrome |
| title_sort | altered central hemodynamics in individuals with down syndrome |
| topic | Down syndrome vascular function sympathetic stimulus autonomic nervous system |
| url | https://www.atlantis-press.com/article/125928186/view |
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