Abstract 19673: Chronic Heart Failure, Aging and Myocardial Fibrosis: Effects of Exercise Training on Left Ventricular Diastolic Dysfunction and Matrix-Metalloproteinases (MMP)
Background: Age-related diastolic dysfunction (DD) is accompanied by increased levels of MMP-2 and -9 as established indicators of myocardial fibrosis. DD has recently also been described in systolic chronic heart failure (CHF). It is, however, unclear if DD can be improved by exercise training (ET) in healthy subjects (HS) and CHF patients and these changes are reflected by lower MMPs.
Methods: We recruited 30 pts. <55 ys. (mean age 45±3 yrs.) and 30 patients >65 ys (mean age 68±4 yrs.) with stable CHF (EF 28±2%, VO2max 14±2ml/kg*min) and 30 healthy subjects (HS) <55 ys. (mean age 46±3) and 30 HS >65 ys (mean age 68±4) (EF 60±1%, VO2max 21±3 ml/kg*min) to a training (T) or a control group (C). Subjects in the T-group exercised 4 times daily at 60-70% of VO2max for 4 wks. under supervision. At baseline and after the intervention E/É ratio was determined by echocardiography. MMP-2 and -9 were measured by ELISA.
Results: As compared to young HS, old HS showed at baseline an increased E/È ratio and increased MMPs (y: E/È 7.2±0.1; MMP-2 20±9 and MMP-9 23±11pg/ml; o: E/È 13.8±0.2; MMP-2 56±13 and MMP-9 76.5±16pg/ml; p<0.05). In CHF pts. diastolic function was impaired and MMP-levels were increased (y: E/È 14.9±0.5; MMP-2 328±36 and MMP-9 276±39pg/ml; o: E/È 14.3±0.2; MMP-2 318±65 and MMP-9 283±79pg/ml) with no difference between y and o. As a result of ET, E/È was reduced by 34% and MMP-levels were reduced by 27% (MMP-2) and 23% (MMP-9) in old HS (p<0.05), while both remained unchanged in C respectively. In y and o pts. with CHF 4 wks. of ET resulted in a significant change in E/È (y: -33.5±2%; p<0,05; o: -35.2±3%; p<0.05) and in MMP-levels (y: MMP-2 -23% MMP-9 -29%; p<0.05; o: MMP-2 -28% MMP-9 -35% p<0.05).
Conclusions: The present trial provides new insight into the age-dependency of ET effects: Among HS aging is associated with the development of diastolic dysfunction and increased MMP levels. In CHF both young and old pts. exhibit a similar degree of diastolic dysfunction and MMP amount. Four weeks of ET are effective in improving diastolic function and MMP levels in old HS and in all age groups of CHF pts. This lusitropic ET effects were not diminished among older pts. underlining the potentials of rehabilitation interventions in an age-group with a high prevalence of CHF.
- © 2010 by American Heart Association, Inc.