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Effect of ageing on left ventricular compliance and distensibility in healthy sedentary humans

Key points  •  Healthy sedentary ageing leads to stiffening of the heart; however, when this process occurs during ageing has been unknown. •  In this study, 70 healthy sedentary subjects were stratified into four groups: ‘young’– G21−34: 21–34 years; ‘early middle‐age’– G35−49: 35–49 years; ‘late middle‐age’– G50−64: 50–64 years; and ‘seniors’– G≥65: ≥65 years. •  Invasive catheter measurements showed a substantially greater left ventricular (LV) compliance (more flexible/less stiff) in G21−34 than G50−64 and G≥65. •  Although LV chamber compliance in G50−64 and G≥65 appeared identical, pressure–volume curves were shifted leftward, exhibiting a smaller volume for any given pressure with increasing age. •  Our results suggest that LV stiffening with ageing occurs during the transition between youth and middle‐age and becomes manifest between the ages of 50–64; LV volume contraction and remodelling follow in the senior years. Early–late middle age thus may represent a ‘sweet spot’ when interventions to prevent stiff ageing hearts may be most effective.