RT Journal Article
SR Electronic
T1 Exercise training in dilated cardiomyopathy improves rest and stress cardiac function without changes in cardiac high energy phosphate metabolism
JF Heart
JO Heart
FD BMJ Publishing Group Ltd and British Cardiovascular Society
SP 1083
OP 1090
DO 10.1136/heartjnl-2012-302145
VO 98
IS 14
A1 Cameron J Holloway
A1 Sairia Dass
A1 Joseph J Suttie
A1 Oliver J Rider
A1 Pete Cox
A1 Lowri E Cochlin
A1 Hamish Jackson
A1 Angela M Fast
A1 Andrew W Johnson
A1 Theodoros D Karamitsos
A1 Stefan Neubauer
A1 Kieran Clarke
YR 2012
UL http://heart.bmj.com/content/98/14/1083.abstract
AB Objective To determine the effects of short-term exercise training on cardiac function and metabolism during rest and physical exercise in patients with heart failure from dilated cardiomyopathy (DCM).Design Patients with DCM (n=15, age 58±2 years, NYHA class I–III) were studied before and after 8 weeks of cycle exercise for 20 min, five times per week.Main outcome measures Cardiac volumes, function and high energy phosphate metabolism were measured using cardiac magnetic resonance during rest and 7 min of acute physical exercise (leg-raising).Results At baseline, average left ventricular ejection fraction (LVEF) was 38±3%, which did not alter during 7 min of exercise. After 8 weeks of home exercise training, there was a 16% improvement in resting LVEF to 44±3% (p<0.01). Training caused a further 20% improvement in LVEF (p<0.05) during acute physical exercise. There was a negative correlation between subjects' baseline level of exercise and change in LVEF (r=−0.67, p<0.05), with sedentary patients having the greatest improvement. Cardiac phosphocreatine (PCr) to ATP ratio did not change during acute physical exercise or after exercise training.Conclusions Short-term exercise training improves resting LVEF and LVEF with acute physical exercise with sedentary patients having the greatest improvement. There were no changes in cardiac PCr to ATP, before or after exercise training, suggesting that the improved cardiac function was not caused by improved energetics. Therefore, peripheral factors likely underlie the improved cardiac function in patients with heart failure after short-term exercise.