Send to

Choose Destination
See comment in PubMed Commons below
Am J Respir Crit Care Med. 2000 Jan;161(1):264-70.

Operation Everest III (Comex '97): modifications of cardiac function secondary to altitude-induced hypoxia. An echocardiographic and Doppler study.

Author information

Service de Réanimation Médicale et Hyperbarie, CHU Salvator, Marseille, France.


During Operation Everest III (Comex '97), to assess the consequences of altitude-induced hypoxia, eight volunteers were decompressed in a hypobaric chamber, with a decompression profile simulating the climb of Mount Everest. Cardiac function was assessed using a combination of M-mode and two-dimensional echocardiography, with continuous and pulsed Doppler at 5,000, 7,000, and 8,000 m as well as 2 d after return to sea level (RSL). On simulated ascent to altitude, aortic and left atrial diameters, left ventricular (LV) diameters, and right ventricular (RV) end-systolic diameter fell regularly. Heart rate (HR) increased at all altitudes accompanied by a decrease in stroke volume; in total, cardiac output (Q) remained unchanged. LV filling was assessed on transmitral and pulmonary venous flow profiles. Mitral peak E velocity decreased, peak A velocity increased, and E/A ratio decreased. Pulmonary venous flow velocities showed a decreased peak D velocity, a decreased peak S velocity, and a reduction of the D/S ratio. Systolic pulmonary arterial pressure (Ppa) showed a progressive and constant increase, as seen on the elevation of the right ventricular/right atrial (RV/RA) gradient pressure from 19.0 +/- 2.4 mm Hg at sea level up to 40.1 +/- 3.3 mm Hg at 8,000 m (p < 0.05), and remained elevated 2 d after recompression to sea level (SL) (not significant). In conclusion, this study confirmed the elevation of pulmonary pressures and the preservation of LV contractility secondary to altitude-induced hypoxia. It demonstrated a modification of the LV filling pattern, with a decreased early filling and a greater contribution of the atrial contraction, without elevation of LV end-diastolic pressure.

[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Atypon
    Loading ...
    Support Center