High altitude residency at 5100 m and chronic mountain sickness were associated with right heart dilatation, left ventricle concentric remodelling, and diastolic dysfunction.
Observational (n=96)
Does living at extreme high altitude and having chronic mountain sickness alter cardiac remodelling and pulmonary hemodynamics compared to healthy lowlanders?
Living at extreme high altitude (5100 m) induces significant right heart dilatation and left ventricular concentric remodelling with diastolic dysfunction, which is exacerbated by chronic mountain sickness.
AIMS: A unique Andean population lives in the highest city of the world (La Rinconada, 5100 m, Peru) and frequently develops a maladaptive syndrome, termed chronic mountain sickness (CMS). Both extreme altitude and CMS are a challenge for the cardiovascular system. This study aims to evaluate cardiac remodelling and pulmonary circulation at rest and during exercise in healthy and CMS highlanders. METHODS AND RESULTS: Highlanders living permanently at 3800 m (n = 23) and 5100 m (n = 55) with (n = 38) or without CMS (n = 17) were compared with 18 healthy lowlanders. Rest and exercise echocardiography were performed to describe cardiac remodelling, pulmonary artery pressure (PAP), and pulmonary vascular resistance (PVR). Total blood volume (BV) and haemoglobin mass were determined in all people. With the increase in the altitude of residency, the right heart dilated with an impairment in right ventricle systolic function, while the left heart exhibited a progressive concentric remodelling with Grade I diastolic dysfunction but without systolic dysfunction. Those modifications were greater in moderate-severe CMS patients. The mean PAP was higher both at rest and during exercise in healthy highlanders at 5100 m. The moderate-severe CMS subjects had a higher PVR at rest and a larger increase in PAP during exercise. The right heart remodelling was correlated with PAP, total BV, and SpO2. CONCLUSION: Healthy dwellers at 5100 m exhibit both right heart dilatation and left ventricle concentric remodelling with diastolic dysfunction. Those modifications are even more pronounced in moderate-severe CMS subjects and could represent the limit of the heart's adaptability before progression to heart failure.
Doutreleau et al. (2022) conducted an observational in Chronic mountain sickness (n=96). High altitude residency and chronic mountain sickness vs. Healthy lowlanders was evaluated on Cardiac remodelling, pulmonary artery pressure (PAP), and pulmonary vascular resistance (PVR) at rest and during exercise. High altitude residency at 5100 m and chronic mountain sickness were associated with right heart dilatation, left ventricle concentric remodelling, and diastolic dysfunction.