The Effects of Prolonged Acute Hypobaric Hypoxia on Novel Measures of Biventricular Performance

Background There are limited data on the effects of prolonged acute hypoxia on individual and global measures of biventricular function. Aims The aim of this study was to assess its effects on conventional and novel measures of biventricular function, including the recently defined E′/(A′×S′) (EAS) index, obtained using pulsed‐wave tissue Doppler Imaging (PWTDI) and associated blood brain natriuretic peptide (BNP) levels. Methods In this study, 14 healthy subjects aged 30.5 years were assessed at baseline and at >150 minutes following hypobaric hypoxia (HH) to the equivalent altitude of 4800 m for a total of 180 minutes. The combined EAS index (E′/(A′ × S′)) was calculated at the mitral and tricuspid annulus using data from the peak systolic (S′) early (E′) and late (A′) diastolic filling. Results It was seen that HH increased resting heart rate (63.4 ± 8.4 vs. 85.2 ± 10.2/min; P