perspective
Cardiac Output Adaptation in Long-Duration Lunar Residents: Echocardiographic Findings at 6, 12, and 24 Months: Population Analysis
Dr. K. Patel
· Lunar Medical Research Cooperative
Lunar Cardiology · Vol. 4, No. 3 · June 29, 2023
Abstract
Follow-up investigation building on prior work. Serial echocardiography in 83 lunar residents demonstrates progressive left ventricular mass reduction and decreased stroke volume over 24 months in 1/6g. Findings are consistent with reduced preload demand and have implications for exercise prescription and cardiovascular medication dosing.
Extended analysis and updated findings. Cardiac deconditioning in microgravity is well documented. The lunar partial-gravity environment attenuates but does not eliminate these changes. We enrolled 83 adult lunar residents aged 24–58 at Copernicus Station and performed echocardiography at baseline and 6-month intervals.
Key findings: LV mass decreased by a mean of 6.4% at 12 months and 9.1% at 24 months. Stroke volume decreased proportionally. Resting cardiac output was maintained through compensatory heart rate increase. Exercise capacity declined in parallel with LV mass.
Cardiovascular medication dosing in lunar residents requires adjustment: beta-blockers reduce a heart rate that is already compensating for reduced stroke volume. We recommend conservative dose reductions of 20–30% for rate-limiting agents.
These findings...
Key findings: LV mass decreased by a mean of 6.4% at 12 months and 9.1% at 24 months. Stroke volume decreased proportionally. Resting cardiac output was maintained through compensatory heart rate increase. Exercise capacity declined in parallel with LV mass.
Cardiovascular medication dosing in lunar residents requires adjustment: beta-blockers reduce a heart rate that is already compensating for reduced stroke volume. We recommend conservative dose reductions of 20–30% for rate-limiting agents.
These findings...
Keywords
cardiac, echocardiography, LV mass, deconditioning, stroke volume, lunar