Impaired myocardial function does not explain reduced left ventricular filling and stroke volume at rest or during exercise at high altitude

Journal of Applied Physiology
Mike StembridgeRob Shave

Abstract

Impaired myocardial systolic contraction and diastolic relaxation have been suggested as possible mechanisms contributing to the decreased stroke volume (SV) observed at high altitude (HA). To determine whether intrinsic myocardial performance is a limiting factor in the generation of SV at HA, we assessed left ventricular (LV) systolic and diastolic mechanics and volumes in 10 healthy participants (aged 32 ± 7; mean ± SD) at rest and during exercise at sea level (SL; 344 m) and after 10 days at 5,050 m. In contrast to SL, LV end-diastolic volume was ∼19% lower at rest (P = 0.004) and did not increase during exercise despite a greater untwisting velocity. Furthermore, resting SV was lower at HA (∼17%; 60 ± 10 vs. 70 ± 8 ml) despite higher LV twist (43%), apical rotation (115%), and circumferential strain (17%). With exercise at HA, the increase in SV was limited (12 vs. 22 ml at SL), and LV apical rotation failed to augment. For the first time, we have demonstrated that EDV does not increase upon exercise at high altitude despite enhanced in vivo diastolic relaxation. The increase in LV mechanics at rest may represent a mechanism by which SV is defended in the presence of a reduced EDV. However, likely because of the higher LV ...Continue Reading

References

Sep 1, 1976·Journal of Applied Physiology·C E TuckerR F Grover
Oct 1, 1992·International Journal of Sports Medicine·J R SuttonC S Houston
Jul 1, 1987·The American Journal of Cardiology·J SuarezC S Houston
Aug 1, 1974·Journal of Applied Physiology·D B Dill, D L Costill
Dec 1, 1967·Journal of Applied Physiology·J K AlexanderR F Grover
Oct 1, 1983·The American Journal of Cardiology·R E Fowles, H N Hultgren
Jun 1, 1983·Clinical Cardiology·J K Alexander, R F Grover
May 1, 1997·Medicine and Science in Sports and Exercise·T D Noakes
Apr 29, 2000·Respiration Physiology·P D Wagner
May 15, 2004·American Journal of Physiology. Heart and Circulatory Physiology·José A L CalbetPeter D Wagner
Aug 27, 2004·Acta Physiologica Scandinavica·M SundstedtE Henriksen
Feb 4, 2006·Journal of Applied Physiology·Andrew R HsuAnne L Friedlander
Feb 7, 2006·European Journal of Echocardiography : the Journal of the Working Group on Echocardiography of the European Society of Cardiology·Roberto M LangUNKNOWN European Association of Echocardiography, European Society of Cardiology
Nov 23, 2007·American Journal of Physiology. Heart and Circulatory Physiology·Yuichi NotomiJames D Thomas
Mar 22, 2008·Journal of the American Society of Echocardiography : Official Publication of the American Society of Echocardiography·Bas M van DalenMarcel L Geleijnse
Oct 8, 2009·Cellular and Molecular Life Sciences : CMLS·José A L CalbetCarsten Lundby
Jan 20, 2010·JACC. Cardiovascular Imaging·Matteo BertiniJeroen J Bax
Apr 10, 2010·The European Respiratory Journal·R NaeijeV Faoro
Apr 27, 2010·Progress in Cardiovascular Diseases·Robert Naeije
Oct 28, 2010·FASEB Journal : Official Publication of the Federation of American Societies for Experimental Biology·Cameron J HollowayUNKNOWN Caudwell Xtreme Everest Research Group
May 17, 2011·American Journal of Physiology. Heart and Circulatory Physiology·Eric J StöhrRob Shave
Aug 15, 2012·The Journal of Physiology·Rory B WeinerAaron L Baggish
May 28, 2013·Journal of the American Society of Echocardiography : Official Publication of the American Society of Echocardiography·Chantal DedobbeleerPhilippe Unger
Aug 8, 2014·Experimental Physiology·Philip N Ainslie

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Citations

Nov 22, 2015·Scandinavian Journal of Medicine & Science in Sports·Christoph Siebenmann, Carsten Lundby
Sep 2, 2015·European Journal of Sport Science·Mike StembridgeRob Shave
Feb 12, 2017·The Journal of Physiology·Alexandra M WilliamsNeil D Eves
May 29, 2016·American Journal of Physiology. Heart and Circulatory Physiology·Lindsey M BouletGlen E Foster
Jun 28, 2016·American Journal of Physiology. Heart and Circulatory Physiology·Michail E KeramidasOla Eiken
Jan 1, 2016·European Heart Journal Cardiovascular Imaging·Claire MaufraisGuillaume Walther
Oct 30, 2018·Scandinavian Journal of Medicine & Science in Sports·Mahdi SarebanJosef Niebauer
Feb 23, 2019·Experimental Physiology·Claire MaufraisSamuel Verges
Oct 22, 2016·American Journal of Physiology. Heart and Circulatory Physiology·William S CheyneNeil D Eves
May 21, 2016·American Journal of Physiology. Heart and Circulatory Physiology·Alexandra M WilliamsNeil D Eves
Jun 3, 2017·Journal of Applied Physiology·Christoph SiebenmannCarsten Lundby
Aug 11, 2020·American Journal of Physiology. Heart and Circulatory Physiology·Tony G DawkinsRob E Shave
Jan 24, 2016·American Journal of Physiology. Heart and Circulatory Physiology·Mike StembridgeRob Shave
Aug 28, 2021·American Journal of Physiology. Heart and Circulatory Physiology·Mike StembridgePhilip N Ainslie

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