Cardiac atrophy after bed rest and spaceflight

• DOI: 10.1152/jappl.2001.91.2.645
• Publication Date: 2017-12-22T21:19:41Z
• Authors: Merja A. Perhonen; Fatima Franco; Lynda D. Lane; Jay C. Buckey; C. Gunnar Blomqvist; Joseph E. Zerwekh; Ronald M. Peshock; Paul T. Weatherall; Benjamin D. Levine
• Keywords: Spaceflight; Rest (music)

Cardiac muscle adapts well to changes in loading conditions. For example, left ventricular (LV) hypertrophy may be induced physiologically (via exercise training) or pathologically hypertension valvular heart disease). If is treated, LV regresses, suggesting a sensitivity work. However, whether physical inactivity nonathletic populations causes adaptive mass even frank atrophy not clear. We exposed previously sedentary men 6 ( n = 5) and 12 3) wk of horizontal bed rest. right (RV) end-diastolic volume were measured using cine magnetic resonance imaging (MRI) at 2, 6, rest; five healthy also studied before after least routine daily activities as controls. In addition, four astronauts the complete elimination hydrostatic gradients during spaceflight 10 days. During rest, decreased by 8.0 ± 2.2% P 0.005) with an additional 7.6 2.3% subjects who remained for wk; there was no change control (153.0 12.2 vs. 153.4 12.1 g, 0.81). Mean wall thickness (4 2.5%, 0.01) rest associated decrease mass, physiological remodeling respect altered load. 14 1.7% 0.002) 2 changed minimally thereafter. After RV free 2.7% 0.06) 16 7.9% 0.06). spaceflight, 6.9% 0.07). conclusion, cardiac occurs prolonged (6 wk) occur short-term spaceflight. suggest that due adaptation reduced myocardial load work real simulated microgravity demonstrates plasticity under different