title: Experimental acute hypoxia in healthy subjects: evaluation of systolic and diastolic function of the left ventricle at rest and during exercise using echocardiography.
abstract: To clarify whether or not systolic and diastolic function of the human left ventricle (LV) were decreased during acute hypoxia, at rest and with exercise, 14 healthy male volunteers [age 25.9 (SD 3.0) years, height 182.9 (SD 7.1) cm, body mass 75.9 (SD 6.9)kg] were examined using M-mode and 2D-mode echocardiography to determine the systolic LV function as well as Doppler-echocardiography for the assessment of diastolic LV function on 2 separate test days. In random order, the subjects breathed either air on 1 day (N) or a gas mixture with reduced oxygen content on the other (H; oxygen fraction in inspired gas 0.14). Measurements on either day were made at rest, several times during incremental cycle exercise in a supine position (6-min increments of 50 W, maximal load 150 W) and in 6th min of recovery. Corresponding measurements during N and H were compared statistically. Arterial O2 tension (PaO2) was normal on N-day. All subjects showed a marked acute hypoxia at rest [PaO2, 54.5 (SD 4.6) mmHg], during exercise and recovery on H-day. The latter was associated with tachycardia compared to N-day. All echocardiographic measurements at rest were within the limits of normal values on both test days. Ejection time, end-systolic and end-diastolic left ventricular dimensions as well as the thickness of left posterior wall and of interventricular septum showed no statistically significant influence of H either at rest or during exercise.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Klinikum der J.W. Goethe-Universität, Medizinische Klinik II, Frankfurt am Main, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Kullmer
authors.forename: G
authors.initials: G
authors.lastname: Kneissl
authors.forename: T
authors.initials: T
authors.lastname: Katova
authors.forename: H
authors.initials: H
authors.lastname: Kronenberger
authors.forename: A
authors.initials: A
authors.lastname: Urhausen
authors.forename: W
authors.initials: W
authors.lastname: Kindermann
authors.forename: W
authors.initials: W
authors.lastname: März
authors.forename: J
authors.initials: J
authors.lastname: Meier-Sydow
mesh_terms: D000328:Adult; D002302:Cardiac Output / Q000502:physiology; D003971:Diastole / Q000502:physiology; D015150:Echocardiography, Doppler; D015444:Exercise / Q000502:physiology*; D006801:Humans; D000860:Hypoxia / Q000503:physiopathology*; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology; D012146:Rest / Q000502:physiology; D016037:Single-Blind Method; D013318:Stroke Volume / Q000502:physiology; D013599:Systole / Q000502:physiology; D016277:Ventricular Function, Left / Q000502:physiology*