Fit pour Voyager? · • Moderate–severe pulmonic valve regurgitation • Sinus of Valsalva fistula/aneurysm • Subvalvular or supravalvular aortic stenosis (except HOCM) • Tetralogy

Michel White MD, FRCPC(C), FACC, FESC

Fit pour Voyager?

Plan de la Presentation

•  Physiologie et exigences de l’altitude •  Les challenges physiologiques chez le patient a haut

risque: Hypertension, arythmies, cardiopathies et MCAS •  Comment stratifier, quoi recommander? •  Quoi faire avec la medication CV?

Physiologie et exigences de l’altitude

Question 1

Hemodynamic adaptations to high altitude

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La réponse cardiovasculaire en reponse a une exposition aigüe à la haute altitude

•  ↑ FC ~16 bpm à 4000 mètres •  Élévation du débit cardiaque •  ↓ légère des volumes cardiaques •  ↑ FEVG (activation sympathique et ↓ de l’activité

vagale) •  La réponse semble indépendante de l’âge et du

sexe.

Altitude-induced autonomic and CV adjustments

Time course of CV and autonomic changes in high

altitude

Exercise increases O2 desaturation at high altitude

Beneficial/detrimental effects of high altitude adjustments with health and

disease state

MAM leger = 1-3; modere = 4-6 ; severe > 6 points

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MAM – Facteurs favorisants et predisposants

•  Vitesse de montee: max 500 metres/ 24 heures > 3000 m  1 semaine pour atteindre 3000- 5000 metres

•  Femme = homme mais oedeme facial plus frequent •  Plus elevee <18 ans et > 50 ans •  Favorisee par exercise intense •  Sujets obeses et migraineux plus a risque de MAM •  Non reliee = capacitee aerobique, entrainement

physique et tabac

Reponse 1

Les challenges physiologiques chez le patient a haut risque: Hypertension, arythmies, cardiopathies

et MCAS

Question 2

20

IVUS data – Proximal LAD

Lund LH and DM Mancini. Int J Cardiol 2008;125:166-171

Decline in peak VO2 with age in men and women

Main pathophysiologic changes and their interactions with CV

conditions

Prevalence of self-reported CVD among high-altitude mountaineers

Chronic conditions affected by altitude exposure

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Hypertension artérielle et la haute altitude

•  Traitement pharmacologique ? Trop ou trop peu •  ↑ de la T.A surtout systolique

─  ↑ Arythmie ─  Hypertension artérielle nocturne

•  Grande susceptibilité individuelle – Le patient hypertendu est-il à risque d’évènement cardiaque à haute altitude ?

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Les adaptations de la circulation coronarienne

•  Régulation du flot coronarien = fréquence cardiaque, contractilité et tension murale

•  Changement aigü: ─  La réserve de flot coronarien (5 à 6 fois) est

suffisante pour repondre aux demandes physiques élevées en haute altitude

•  Chroniquement: ─  ↓ du flot coronarien comparé au niveau de la mer

(~ 30% altitude des Andes) ─  ↓ de la fréquence cardiaque, polyglobulie, ↑ de la

différence artério-veineuse = identique au changement de la circulation périphérique.

27 MW 03-2006

Impact of hypoxemia and high altitude (5245m) on hemodynamics and gas exchange parameters in healthy climbers

Ghofrani HA, et al. Ann Int Med 2004; 141: 169-177

Systolic blood pressure (mmHg)

Heat rate (bpm)

Saturation (%)

Systolic pulmonary artery pressure (mmHg)

Cardiac output (L/min)

Maximum level of exercise (W)

148.0

76.0

99.0

17.5

6.0

--

Rest Normoxic

232.0

171.0

98.0

25.1

14.4

262.5

Stress

142.5

84.8

72.0

30.5

5.1

--

Rest Hypoxic

209.5

157.3

60.8

42.9

11.1

130.6

Stress

120.0

84.0

83.0

22.0

5.6

--

Rest Sidenafil

185.0

148.5

71.0

27.5

15.1

189.5

Stress

Low altitude High altitude

Categories of Disease Complexity in Congenital Heart Disease

Simple congenital heart disease •  Isolated congenital aortic or mitral valve disease •  Isolated patent foramen ovale or small atrial septal

defect •  Isolated small ventricular septal defect without

associated lesions •  Mild pulmonic stenosis •  Previously ligated or occluded patent ductus arteriosus •  Repaired secundum or sinus venosus atrial septal defect

without residua •  Repaired ventricular septal defect without residua


Moderate severity congenital heart disease •  Aorto-left ventricular fistulae •  Total or partial anomalous pulmonary venous return •  Partial or complete atrioventricular canal defects •  Coarctation of the aorta •  Ebstein’s anomaly •  Infundibular right ventricular outflow obstruction of significance •  Ostium primum or sinus venosus atrial septal defect •  Patent ductus arteriosus (not closed) •  Moderate–severe pulmonic valve regurgitation •  Sinus of Valsalva fistula/aneurysm •  Subvalvular or supravalvular aortic stenosis (except HOCM) •  Tetralogy of Fallot •  Ventricular septal defect with absent valve(s), aortic regurgitation,

coarctation, mitral disease, right ventricular outflow obstruction, straddling tricuspid/mitral valve, or subaortic stenosis


Congenital heart disease of great complexity •  Conduits (valved or nonvalved) •  Cyanotic congenital heart disease (all forms) •  Double-outlet ventricle •  Eisenmenger syndrome •  Fontan procedure •  Mitral or tricuspid atresia •  Single ventricle •  Pulmonary atresia (all forms) •  Pulmonary vascular obstructive diseases •  Transposition of the great arteries •  Truncus arteriosus/hemitruncus •  Other abnormalities of atrioventricular or ventriculoarterial connection

(crisscross heart, isomerism, heterotaxy syndromes ventricular inversion)

Reponse 2

Comment stratifier, quoi recommander?

Question 3

Prerequisites, general recommendations, and contraindications to high altitude

exposure

General prerequisites at low altitude •  Stable clinical condition •  Asymptomatic at rest •  Functional class < II NYHA


exposure General recommendations at high altitude •  Ascent at a slow rate > 2000 m (increasing

sleeping altitude by < 300 m/d) •  Avoid overexertion •  Avoid direct transportation to an altitude >

3000 m


exposure Absolute contraindications to high altitude exposure •  Unstable clinical condition, ie,

- unstable angina - symptoms or signs of ischemia during exercise testing at low to

•  moderate workload (<80 W or <5 metabolic equivalents) - decompensated heart failure - uncontrolled atrial or ventricular arrhythmia

•  Myocardial infarction and/or coronary revascularization in the past 3-6 mo

•  Decompensated heart failure during the past 3 mo •  Poorly controlled arterial hypertension (blood pressure ≥ 160/100

mm Hg at rest, > 220 mm Hg systolic blood pressure during exercise)


exposure Absolute contraindications to high altitude exposure (suite) •  Marked pulmonary hypertension (mean pulmonary artery pressure >

30 mm Hg, RV-RA gradient > 40 mm Hg) and/or any pulmonary hypertension associated with functional class ≥ II and/or presence of markers of poor prognosis37

•  Severe valvular heart disease, even if asymptomatic •  Thromboembolic event during the past 3 mo •  Cyanotic or severe acyanotic congenital heart disease •  ICD implantation or ICD intervention for ventricular arrhythmias in

the past 3-6 mo •  Stroke, transient ischemic attack, or cerebral hemorrhage during the

past 3-6 mo

Recommendations and preexposure assessment according to CV disease

Clinical Condition Proposed Preexposure Assessment and Recommendations for patients

Arterial hypertension If not well controlled → ambulatory blood pressure recording Instructions for self-monitoring of blood pressure and treatment adjustments if uncontrolled hypertension or hypotension develops

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Maladie coronarienne et la haute altitude

•  ↓ du risque MCAS et IM chez les résidents haute altitude

•  Vasoconstriction coronarienne possible en présence de dysfonction endothéliale et MCAS

•  Hypoxémie = moins stressant pour le cœur que l’exercice

•  Le rôle de l’hypoxémie souvent combinée avec l’exercice intense, le froid et le stress émotionnel



CAD Asymptomatic revascularization < 6 mo

Asymptomatic revascularization > 6 mo

Asymptomatic reduced LVEF

Consider exercise testing according to coronary status Exercise testing If not conclusive → exercise testing with imaging modality Exercise testing If not conclusive → exercise testing with imaging modality Transthoracic echocardiography at rest

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Évaluation du patient à risque CV

•  Épreuve d’effort (capacité maximale, récupération FC 1 et 2 min)

•  Épreuve d’effort avec analyses des gaz expiratoires •  Épreuve d’effort avec MIBI ou échocardiographie •  CCTA (Angio IRM) •  Angiographie coronarienne •  Holter ou cardiomémo ?

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L’altitude contribue-t-elle à la décompensation du patient insuffisant cardiaque ?

•  L’ascension est sécuritaire jusqu’à 2,500 mètres chez le patient bien compensé

•  Il y aurait rétention hydrosodée associé à l’AMS rendant le patient défaillant plus à risque

•  La majoration des diurétiques, le diamox, sildenafil sont à considérer

•  Ajustement de la médication concomitante ?



Reduced LVEF Any cause

Exercise testing Transthoracic echocardiography at rest Instructions for treatment adjustments if heart failure develops



Pulmonary hypertension Exposure contraindicated if marked pulmonary hypertension or if functional class > I (see Table 2) Echocardiographic assessment of RV function and of pulmonary artery pressure under simulated high altitude (FIO2: 12%; if RV-RA gradient > 40 mm Hg patients should be strongly discouraged)



Valvular heart disease Symptomatic and/or severe Mild aortic or mitral regurgitation

Exposure contraindicated Exercise testing, transthoracic echocardiography at rest Instructions for self-monitoring of blood pressure and treatment adjustments if uncontrolled hypertension or hypotension develops Instructions for self-monitoring of international normalized ratio and dosis adaptation



Congenital heart disease Acyanotic or cyanotic Exposure contraindicated if functional

class > I Exercise testing and echocardiographic assessment of left and RV function and pulmonary pressure under simulated high altitude (FIO2, 12%; if RV-RA gradient > 40 mm Hg patients should be strongly discouraged)

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La haute altitude provoque-t-elle des arythmies cardiaques ?

•  ESV ↑ de 63% en réponse à l’ascension rapide. Ceci est couplé d’une ↑ de norepinéphrine de 67%.

•  Impact de l’altitude sur les arythmies supra ventriculaires indépendamment de l’effort et de la température froide demeure inconnu



Arrhythmia Associated with CAD/CHF Pacemaker

Supraventricular tachycardia/atrial flutter

Paroxysmal or persistent atrial fibrillation

Exercise testing Testing only if VVIR, DDDR, or AAIR mode to adapt PM rates Consider catheter ablation before high-altitude exposure Exercise testing and Holter-ECG Instruction for heart rate self-monitoring and therapy adjustments in case of insufficient rate control (>90 beats per min at rest)

Clinical Condition Proposed Preexposure Assessment and

Recommendations for patients Cerebrovascular disease All conditions Ischemic stroke or TIA b 90 d ago

Ischemic stroke or TIA N 90 d ago, thorough workup of the stroke has been performed and risk factors are treated adequately

Stenosis or occlusion of a major extra- or intracranial cerebral artery

Hypertensive hemorrhage

Hemorrhage as a result of amyloid angiopathy Known cerebral aneuryms, arteriovenous malformation, or cerebral cavernoma

Avoid trekking or climbing alone Avoid traveling to higher altitudes (>2000-2500 m) Avoid air travel Avoid extreme altitude > 4500 m

Avoid traveling to altitude > 2000-2500 m

Travel to high altitude only if blood pressure is controlled and not before 90 d after the event Avoid high altitude Check blood pressure. Avoid extreme altitude > 4500 m

Recommendations and preexposure assessment according

to CV disease

51

Facing our limits 6120m

MW 03-2007

Capacite physique requise pour la haute montagne

•  Endurance musculaire et cardiovasculaire •  Capacitee de travailler sans oxygene – amelioration du

seuil ventilatoire •  Force exceptionelle au niveau des cuisses, dos et epaules •  Stabilisation au niveau du “core” •  Bonne flexibilitee •  Capacitee de relaxation

“There are three kinds of lies: lies, damned lies, and statistics”

MW 2002-03

Links between physiologic systems and the sources

of perceived sensation limiting exercise in humans Motor command

Excitation - contraction (Na+ - K+)

Cross-bridge formation (Ca2+)

Glycogen + ADP → ATP + Lactate + H+

Glycogen + ADP + O2 → ATP + CO2

FFA + ADP + O2 → ATP + CO2

Process

Brain

System

Effort

Sensation

Power output (ATP → ADP)

Nerve Weakness

Muscle Tension

Metabolism Fatigue

Blood flow

Ventilation O2 CO2

Circulation

Lungs Epstein FH, NEJM 2000; 31: 632-641

Relationship between mitochondrial volume and number of capillaries in humans

Esposito F, at al. J Am Coll Cardiol 2010;55:1945-54

MW 2003

Exercise conditioning training improves submaximal exercise capacity in older CAD patients

Ades PA et al. Circulation 1993; 88: 572-577

Rest HR Systolic BB

Low submaximal exercise Intensity (% VO2 max) HR Serum lactate Perceived exertion

High submaximal exercise Intensity (% VO2 max) HR Serum lactate Perceived exertion

Submaximal exercise duration Mean exercise time (min) Complete 45-min protocol

70 ± 16 135 ± 25

58 ± 17% 94 ± 16

1.85 ± 0.96 9.9 ± 2.6

79 ± 14% 108 ± 16

2.30 ± 1.08 14.0 ± 2.2

30 ± 10 10/45 (22%)

Baseline (n = 45)

68 ± 14 134 ± 21

50 ± 8* 84 ± 12

1.44 ± 0.46* 8.7 ± 2.2*

67 ± 10%* 97 ± 16*

1.60 ± 0.43* 11.7 ± 2.2*

41 ± 10* 33/43 (77%)*

3 months conditioning

(n = 43)

68 ± 1* 122 ± 20*†

46 ± 7* 84 ± 10*

1.39 ± 0.26* 7.9 ± 1.2*

55 ± 12%*† 97 ± 10*

1.60 ± 0.41* 11.5 ± 2.5*

43 ± 7* 10/11 (91%)*

12 months conditioning

(n = 11)

* p < 0.05 vs baseline † p < 0.05 vs 3 months’ conditioning

Reponse 3

MW 2008-01 58

Le patient à bas risque

•  Hypertension artérielle traitée •  Patients diabétiques •  Sujets «jeunes» ou «âgés» •  Maladies coronariennes athérosclérotiques minimes •  Statut post-dilatation coronarienne ou pontages

aorto-coronariens •  Statut post infarctus du myocarde sans dysfonction

ventriculaire gauche résiduelle

MW 2008-01 59

Le patient à risque modéré

•  Angine d’effort stable avec seuil ischémique élevé •  Maladie coronarienne athérosclérotique documentée

(uni ou bi tronculaire) •  Dysfonction ventriculaire gauche asymptomatique

(FEVG ≥40%) •  Hypertension artérielle labile •  Arythmie supra-ventriculaire ou ventriculaire traitées

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Le patient à risque élevé

•  Ces patients devraient vraisemblablement s’abstenir d’une exposition et une altitude modérée (1000- 2500 m) ─  Patients porteurs de cardiopathie cyanogène ─  Toute forme d’hypertension artérielle pulmonaire ─  Dysfonction ventriculaire gauche avec F.E. à 40% ─  Hypertension artérielle mal contrôlée ─  Maladie coronarienne athérosclérotique de plusieurs

troncs vasculaires avec seuil ischémique bas ─  Arythmie cardiaque mal controlée

Quoi faire avec la RX cardiovasculaire?

Question 4

Medication for the prevention and treatment of AMS

PDE5Is for HAPE and HAPH

BP reduction with PDE5Is

Reponse 4

Documents

Fit pour Voyager? · • Moderate–severe pulmonic valve regurgitation • Sinus of Valsalva fistula/aneurysm • Subvalvular or supravalvular aortic stenosis (except HOCM) • Tetralogy