Clinical recommendations for high altitude exposure of individuals with pre-existing cardiovascular conditions: A joint statement by the European Society of Cardiology, the Council on Hypertension of the European Society of Cardiology, the European Society of Hypertension, the International Society of Mountain Medicine, the Italian Society of Hypertension and the Italian Society of Mountain Medicine

Gianfranco Parati, Piergiuseppe Agostoni, Buddha Basnyat, Grzegorz Bilo, Hermann Brugger, Antonio Coca, Luigi Festi, Guido Giardini, Alessandra Lironcurti, Andrew M Luks, Marco Maggiorini, Pietro A Modesti, Erik R Swenson, Bryan Williams, Peter Bärtsch, Camilla Torlasco, Gianfranco Parati, Piergiuseppe Agostoni, Buddha Basnyat, Grzegorz Bilo, Hermann Brugger, Antonio Coca, Luigi Festi, Guido Giardini, Alessandra Lironcurti, Andrew M Luks, Marco Maggiorini, Pietro A Modesti, Erik R Swenson, Bryan Williams, Peter Bärtsch, Camilla Torlasco

Abstract

Take home figureAdapted from Bärtsch and Gibbs2 Physiological response to hypoxia. Life-sustaining oxygen delivery, in spite of a reduction in the partial pressure of inhaled oxygen between 25% and 60% (respectively at 2500 m and 8000 m), is ensured by an increase in pulmonary ventilation, an increase in cardiac output by increasing heart rate, changes in vascular tone, as well as an increase in haemoglobin concentration. BP, blood pressure; HR, heart rate; PaCO2, partial pressure of arterial carbon dioxide.

Figures

Take home figure
Take home figure
Adapted from Bärtsch and Gibbs Physiological response to hypoxia. Life-sustaining oxygen delivery, in spite of a reduction in the partial pressure of inhaled oxygen between 25% and 60% (respectively at 2500 m and 8000 m), is ensured by an increase in pulmonary ventilation, an increase in cardiac output by increasing heart rate, changes in vascular tone, as well as an increase in haemoglobin concentration. BP, blood pressure; HR, heart rate; PaCO2, partial pressure of arterial carbon dioxide.
Figure 1
Figure 1
Altitude classification (Imray et al.1S) (left column); corresponding barometric pressure and fraction in inspired oxygen for different simulated altitudes in a laboratory setting, according to the 1976 US standard Atmosphere by NASA.5S (central two columns); relationship between altitude2S and environmental characteristics (temperature, humidity, and solar radiation) (box on the right-hand side). We used the 1976 US standard atmosphere model by NASA to estimate barometric pressure at a given altitude, because the former is a function not only of altitude but also of latitude. For similar altitudes, barometric pressure (and consequently also partial pressure of arterial oxygen) is higher the closer we are to the equator line.
Take home figure
Take home figure
Adapted from Bärtsch and Gibbs Physiological response to hypoxia. Life-sustaining oxygen delivery, in spite of a reduction in the partial pressure of inhaled oxygen between 25% and 60% (respectively at 2500 m and 8000 m), is ensured by an increase in pulmonary ventilation, an increase in cardiac output by increasing heart rate, changes in vascular tone, as well as an increase in haemoglobin concentration. BP, blood pressure; HR, heart rate; PaCO2, partial pressure of arterial carbon dioxide.
Figure 2
Figure 2
Systolic blood pressure profile for 24 h in a healthy volunteer at different altitudes. Blue line: sea level; yellow line: Namche Bazaar (3400 m); red line: Everest Base Camp 1 (5400 m).

References

    1. For References [1S–48S], please refer to Supplementary material online.
    1. Agostoni P. Considerations on safety and treatment of patients with chronic heart failure. High Alt Med Biol 2013;14:96–100.
    1. Bärtsch P, Gibbs JS.. Effects of altitude on the heart and the lungs. Circulation 2007;116:2191–2202.
    1. Donegani E, Hillebrandt D, Windsor J, Gieseler U, Rodway G, Schöffl V, Küpper T.. Pre-existing cardiovascular conditions and high-altitude travel. Consensus statement of the Medical Commission of the Union Internationale des Associations d’Alpinisme (UIAA MedCom). Travel Medicine and Infectious Disease. Travel Med Infect Dis 2014;12:237–252.
    1. Agostoni P, Swenson ER, Bussotti M, Revera M, Meriggi P, Faini A, Lombardi C, Bilo G, Giuliano A, Bonacina D, Modesti PA, Mancia G, Parati G.. High-altitude exposure of three weeks duration increases lung diffusing capacity in humans. J Appl Physiol (1985) 2011;110:1564–1571.
    1. Messerli-Burgy N, Meyer K, Steptoe A, Laederach-Hofmann K.. Autonomic and cardiovascular effects of acute high-altitude exposure after myocardial infarction and in normal volunteers. Circ J 2009;73:1485–1491.
    1. Heistad DD, Abboud FM.. Circulatory adjustments to hypoxia. Circulation 1980;61:463–470.
    1. Parati G, Bilo G, Faini A, Bilo B, Revera M, Giuliano A, Lombardi C, Caldara G, Gregorini F, Styczkiewicz K, Zambon A, Piperno A, Modesti PA, Agostoni P, Mancia G.. Changes in 24 h ambulatory blood pressure and effects of angiotensin II receptor blockade during acute and prolonged high-altitude exposure: a randomized clinical trial. Eur Heart J 2014;35:3113–3122.
    1. Bilo G, Caldara G, Styczkiewicz K, Revera M, Lombardi C, Giglio A, Zambon A, Corrao G, Faini A, Valentini M, Mancia G, Parati G.. Effects of selective and non- selective beta-blockade on 24-h ambulatory blood pressure under hypobaric hypoxia at altitude. J Hypertens 2011;29:380–387.
    1. Parati G, Revera M, Giuliano A, Faini A, Bilo G, Gregorini F, Lisi E, Salerno S, Lombardi C, Ramos Becerra CG, Mancia G, Salvi P.. Effects of acetazolamide on central blood pressure, peripheral blood pressure, and arterial distensibility at acute high altitude exposure. Eur Heart J 2013;34:759–766.
    1. Reeves JT, Groves BM, Sutton JR, Wagner PD, Cymerman A, Malconian MK, Rock PB, Young PM, Houston CS.. Operation Everest II: preservation of cardiac function at extreme altitude. J Appl Physiol 1987;63:531–539.
    1. Boussuges A, Molenat F, Burnet H, Cauchy E, Gardette B, Sainty JM, Jammes Y, Richalet JP.. Operation Everest III (Comex '97): modifications of cardiac function secondary to altitude-induced hypoxia. An echocardiographic and Doppler study. Am J Respir Crit Care Med 2000;161:264–270.
    1. De Vries ST, Komdeur P, Aalbersberg S, van Enst GC, Breeman A, van’t Hof AW.. Effects of altitude on exercise level and heart rate in patients with coronary artery disease and healthy controls. Neth Heart J 2010;18:118–121.
    1. Valentini M, Revera M, Bilo G, Caldara G, Savia G, Styczkiewicz K, Parati S, Gregorini F, Faini A, Branzi G, Malfatto G, Magrì D, Agostoni P, Parati G.. Effects of beta-blockade on exercise performance at high altitude: a randomized, placebo-controlled trial comparing the efficacy of nebivolol versus carvedilol in healthy subjects. Cardiovasc Ther 2012;30:240–248.
    1. Agostoni P, Swenson ER, Fumagalli R, Salvioni E, Cattadori G, Farina S, Bussotti M, Tamplenizza M, Lombardi C, Bonacina D, Brioschi M, Caravita S, Modesti P, Revera M, Giuliano A, Meriggi P, Faini A, Bilo G, Banfi C, Parati G.. Acute high-altitude exposure reduces lung diffusion: data from the HIGHCARE Alps project. Respir Physiol Neurobiol 2013;188:223–228.
    1. Pratali L, Cavana M, Sicari R, Picano E.. Frequent subclinical high-altitude pulmonary edema detected by chest sonography as ultrasound lung comets in recreational climbers. Crit Care Med 2010;38:1818–1823.
    1. Caravita S, Faini A, Lombardi C, Valentini M, Gregorini F, Rossi J, Meriggi P, Di Rienzo M, Bilo G, Agostoni G, Parati G.. Sex and acetazolamide effects on chemoreflex and periodic breathing during sleep at altitude. Chest 2015;147:120–131.
    1. Sutton JR, Houston CS, Mansell AL, McFadden MD, Hackett PM, Rigg JR, Powles AC.. Effect of acetazolamide on hypoxemia during sleep at high altitude. N Engl J Med 1979;301:1329–1331.
    1. Penaloza D, Arias-Stella J.. The heart and pulmonary circulation at high altitudes: healthy highlanders and chronic mountain sickness. Circulation 2007;115:1132–1146.
    1. Bailey DM, Dehnert C, Luks AM, Menold E, Castell C, Schendler G, Faoro V, Gutowski M, Evans KA, Taudorf S, James PE, McEneny J, Young IS, Swenson ER, Mairbäurl H, Bärtsch P, Berger MM.. High-altitude pulmonary hypertension is associated with a free radical-mediated reduction in pulmonary nitric oxide bioavailability. J Physiol 2010;588:4837–4847.
    1. Osculati G, Revera M, Branzi G, Faini A, Malfatto G, Bilo G, Giuliano A, Gregorini F, Ciambellotti F, Lombardi C, Agostoni P, Mancia G, Parati G; on behalf of HIGHCARE Investigators. Effects of hypobaric hypoxia exposure at high altitude on left ventricular twist in healthy subjects: data from HIGHCARE study on Mount Everest. Eur Heart J Cardiovasc Imaging 2016;17:635–643.
    1. Holloway CJ, Montgomery HE, Murray AJ, Cochlin LE, Codreanu I, Hopwood N, Johnson AW, Rider OJ, Levett DZ, Tyler DJ, Francis JM, Neubauer S, Grocott MP, Clarke K; Caudwell Xtreme Everest Research Group. Cardiac response to hypobaric hypoxia: persistent changes in cardiac mass, function, and energy metabolism after a trek to Mt. Everest Base Camp. FASEB J 2011;25:792–796.
    1. Martin DS, Pate JS, Vercueil A, Doyle PW, Mythen MG, Grocott MP; Caudwell Xtreme Everest Research Group. Reduced coagulation at high altitude identified by thromboelastography. Thromb Haemost 2012;107:1066–1071.
    1. Modesti PA, Rapi S, Paniccia R, Bilo G, Revera M, Agostoni P, Piperno A, Cambi GE, Rogolino A, Biggeri A, Mancia G, Gensini GF, Abbate R, Parati G.. Index measured at an intermediate altitude to predict impending acute mountain sickness. Med Sci Sports Exerc 2011;43:1811–1818.
    1. Agostoni P, Cattadori G, Guazzi M, Bussotti M, Conca C, Lomanto M, Marenzi G, Guazzi MD.. Effects of simulated altitude-induced hypoxia on exercise capacity in patients with chronic heart failure. Am J Med 2000;109:450–455.
    1. Schmid J, Nobel D, Brugger N, Novak J, Palau P, Trepp A, Wilhelm M, Saner H.. Short-term high altitude exposure at 3454 m is well tolerated in patients with stable heart failure. Eur J Heart Fail 2015;17:182–186.
    1. Lombardi C, Meriggi P, Agostoni PG, Faini A, Bilo G, Revera M, Caldara G, Di Rienzo M, Castiglioni P, Bussotti M, Gregorini F, Mancia G, Parati G.. High altitude hypoxia and periodic breathing during sleep: gender-related differences. J Sleep Res 2013;22:322–330.
    1. Wyss CA, Koepfli P, Fretz G, Seebauer M, Schirlo C, Kaufman PA.. Influence of altitude exposure on coronary flow reserve. Circulation 2003;108:1202–1207.
    1. Salvi P, Revera M, Faini A, Giuliano A, Gregorini F, Agostoni P, Becerra CG, Bilo G, Lombardi C, O’Rourke MF, Mancia G, Parati G.. Changes in subendocardial viability ratio with acute high-altitude exposure and protective role of acetazolamide. Hypertension 2013;61:793–799.
    1. Caravita S, Faini A, Bilo G, Revera M, Giuliano A, Gregorini F, Rossi J, Villafuerte FC, Salvi P, Agostoni P, Parati G.. Ischemic changes in exercise ECG in a hypertensive subject acutely exposed to high altitude. Possible role of a high-altitude induced imbalance in myocardial oxygen supply-demand. Int J Cardiol 2014;171:e100–e102.
    1. Schmid J-P, Noveanu M, Gaillet R, Hellige G, Wahl A, Saner H.. Safety and exercise tolerance of acute high altitude exposure (3454 m) among patients with coronary artery disease. Heart 2006;92:921–925.
    1. de Vries ST, Kleijn SA, van’t Hof AWJ, Snaak H, van Enst GC, Kamp O, Breeman A.. Impact of high altitude on echocardiographically determined cardiac morphology and function in patients with coronary artery disease and healthy controls. Eur J Echocardiogr 2010;11:446–450.
    1. Wu T, Ding S, Kayser B.. Work at high altitude after coronary stenting: safe? Wilderness Environ Med 2010;21:86–87.
    1. Basavarajaiah S, O’Sullivan M.. Physical exertion at high altitude-another risk factor for coronary stent thrombosis? J Invasive Cardiol 2013;25:E66–E68.
    1. Liu Y, Zhang JH, Gao XB, Wu XJ, Yu J, Chen JF, Bian SZ, Ding XH, Huang L.. Correlation between blood pressure changes and AMS, sleeping quality and exercise upon high-altitude exposure in young Chinese men. Mil Med Res 2014;1:19..
    1. Bilo G, Villafuerte FC, Faini A, Anza-Ramírez C, Revera M, Giuliano A, Caravita S, Gregorini F, Lombardi C, Salvioni E, Macarlupu JL, Ossoli D, Landaveri L, Lang M, Agostoni P, Sosa JM, Mancia G, Parati G.. Ambulatory blood pressure in untreated and treated hypertensive patients at high altitude: the High Altitude Cardiovascular Research-Andes study. Hypertension 2015;65:1266–1272.
    1. Wu T-Y, Ding SQ, Liu JL, Yu MT, Jia JH, Chai ZC, Dai RC, Zhang SL, Li BY, Pan L, Liang BZ, Zhao JZ, Qi DT, Sun YF, Kayser B.. Who should not go high: chronic disease and work at altitude during construction of the Qinghai-Tibet railroad. High Alt Med Biol 2007;8:88–10 7.
    1. Kujaník S, Snincák M, Vokál J, Podracký J, Koval J.. Periodicity of arrhythmias in healthy elderly men at the moderate altitude. Physiol Res 2000;49:285–287.
    1. Gibelli G, Fantoni C, Anzà C, Cattaneo P, Rossi A, Montenero A, Baravelli M.. Arrhythmic risk evaluation during exercise at high altitude in healthy subjects: role of microvolt T-wave alternans. Pacing Clin Electrophysiol 2008;31:1277–1283.
    1. Weilenmann D, Duru F, Schönbeck M, Schenk B, Zwicky P, Russi EW, Candinas R.. Influence of acute exposure to high altitude and hypoxemia on ventricular stimulation thresholds in pacemaker patients. Pacing Clin Electrophysiol 2000;23:512–515.
    1. Luks AM, Stout K, Swenson ER.. Evaluating the safety of high-altitude travel in patients with adult congenital heart disease. Congenit Heart Dis 2010;5:220–232.
    1. Staempfli R, Schmid JP, Schenker S, Eser P, Trachsel LD, Deluigi C, Wustmann K, Thomet C, Greutmann M, Tobler D, Stambach D, Wilhelm M, Schwerzmann M.. Cardiopulmonary adaptation to short-term high altitude exposure in adult Fontan patients. Heart 2016;102:1296–1301.
    1. Vargas E, Spielvogel H.. Chronic mountain sickness, optimal hemoglobin, and heart disease. High Alt Med Biol 2006;7:138–149.
    1. Berman W Jr, Wood SC, Yabek SM, Dillon T, Fripp RR, Burstein R.. Systemic oxygen transport in patients with congenital heart disease. Circulation 1987;75:360–368.
    1. Broberg CS, Uebing A, Cuomo L, Thein SL, Papadopoulos MG, Gatzoulis MA.. Adult patients with Eisenmenger syndrome report flying safely on commercial airlines. Heart 2006;93:1599–1603.
    1. Clarke C. Acute mountain sickness: medical problems associated with acute and subacute exposure to hypobaric hypoxia. Postgrad Med J 2006;82:748–753.
    1. Le Roux G, Larmignat P, Marchal M, Richalet J.. Haemostasis at high altitude. Int J Sports Med 1992;13:S49–S51.
    1. Van Osta A, Moraine J-J, Melot C, Mairbaurl H, Maggiorini M, Naeije R.. Effects of high altitude exposure on cerebral hemodynamics in normal subjects. Stroke 2005;36:557–560.
    1. Jha SK, Anand AC, Sharma V, Kumar N, Adya CM.. Stroke at high altitude: Indian experience. High Alt Med Biol 2002;3:21–27.
    1. Niaz A, Nayyar S.. Cerebrovascular stroke at high altitude. J Coll Physicians Surg Pak 2003;13:446–448.
    1. Wilson MH, Newman S, Imray CH.. The cerebral effects of ascent to high altitudes. Lancet Neurol 2009;8:175–191.

Source: PubMed

3
Subscribe