Figure 2. Alterations to cardiac pressures and dimensions with acclimatization or adaptation to hypoxia/high‐altitude.

Left: normal health range of atrial and pulmonary arterial pressures, as well as ventricular‐septal geometry, at sea level or long‐term normoxia. Right: shifts in these parameters with prolonged or lifelong hypoxia. Here, atrial pressures are lowered as a result of reduced filling via lower blood volume, as well as hypoxic pulmonary vasoconstriction, which imposes a greater afterload on the right side of the heart, reduces right ventricular (RV) output and leads to RV expansion. Consequently, left ventricular (LV) end‐diastolic volume and left‐sided filling are reduced via direct ventricular interaction (septal shift) and series ventricular interaction (reduced RV output due to higher afterload). Figure based on reports from (Boussuges et al., 2000; Fowles & Hultgren, 1983; Reeves et al., 1990, 1987)