| Title |
Left ventricular adaptation to high altitude: speckle tracking echocardiography in lowlanders, healthy highlanders and highlanders with chronic mountain sickness
|
|---|---|
| Published in |
The International Journal of Cardiovascular Imaging, February 2015
|
| DOI | 10.1007/s10554-015-0614-1 |
| Pubmed ID | |
| Authors |
Chantal Dedobbeleer, Alia Hadefi, Aurelien Pichon, Francisco Villafuerte, Robert Naeije, Philippe Unger |
| Abstract |
Hypoxic exposure depresses myocardial contractility in vitro, but has been associated with indices of increased cardiac performance in intact animals and in humans, possibly related to sympathetic nervous system activation. We explored left ventricular (LV) function using speckle tracking echocardiography and sympathetic tone by spectral analysis of heart rate variability (HRV) in recently acclimatized lowlanders versus adapted or maladapted highlanders at high altitude. Twenty-six recently acclimatized lowlanders, 14 healthy highlanders and 12 highlanders with chronic mountain sickness (CMS) were studied. Control measurements at sea level were also obtained in the lowlanders. Altitude exposure in the lowlanders was associated with slightly increased blood pressure, decreased LV volumes and decreased longitudinal strain with a trend to increased prevalence of post-systolic shortening (p = 0.06), whereas the low frequency/high frequency (LF/HF) ratio increased (1.62 ± 0.81 vs. 5.08 ± 4.13, p < 0.05) indicating sympathetic activation. Highlanders had a similarly raised LF/HF ratio, but no alteration in LV deformation. Highlanders with CMS had no change in LV deformation, no significant increase in LF/HF, but decreased global HRV still suggestive of increased sympathetic tone, and lower mitral E/A ratio compared to healthy highlanders. Short-term altitude exposure in lowlanders alters indices of LV systolic function and increases sympathetic nervous system tone. Life-long altitude exposure in highlanders is associated with similar sympathetic hyperactivity, but preserved parameters of LV function, whereas diastolic function may be altered in those with CMS. Altered LV systolic function in recently acclimatized lowlanders may be explained by combined effects of hypoxia and changes in loading conditions. |
X Demographics
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Geographical breakdown
| Country | Count | As % |
|---|---|---|
| United States | 1 | 50% |
| Unknown | 1 | 50% |
Demographic breakdown
| Type | Count | As % |
|---|---|---|
| Members of the public | 2 | 100% |
Mendeley readers
The data shown below were compiled from readership statistics for 43 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Spain | 1 | 2% |
| Unknown | 42 | 98% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Other | 6 | 14% |
| Student > Ph. D. Student | 6 | 14% |
| Student > Bachelor | 6 | 14% |
| Student > Doctoral Student | 3 | 7% |
| Student > Postgraduate | 3 | 7% |
| Other | 10 | 23% |
| Unknown | 9 | 21% |
| Readers by discipline | Count | As % |
|---|---|---|
| Medicine and Dentistry | 11 | 26% |
| Agricultural and Biological Sciences | 4 | 9% |
| Psychology | 4 | 9% |
| Sports and Recreations | 3 | 7% |
| Neuroscience | 2 | 5% |
| Other | 7 | 16% |
| Unknown | 12 | 28% |
Attention Score in Context
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All research outputs
#20,657,128
of 25,374,917 outputs
Outputs from The International Journal of Cardiovascular Imaging
#1,292
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Outputs of similar age
#273,566
of 366,748 outputs
Outputs of similar age from The International Journal of Cardiovascular Imaging
#22
of 47 outputs
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