RT Journal Article
SR Electronic
T1 Impact of age on the association between cardiac high-energy phosphate metabolism and cardiac power in women
JF Heart
JO Heart
FD BMJ Publishing Group Ltd and British Cardiovascular Society
SP 111
OP 118
DO 10.1136/heartjnl-2017-311275
VO 104
IS 2
A1 Maria Nathania
A1 Kieren G Hollingsworth
A1 Matthew Bates
A1 Christopher Eggett
A1 Michael I Trenell
A1 Lazar Velicki
A1 Petar M Seferovic
A1 Guy A MacGowan
A1 Doug M Turnbull
A1 Djordje G Jakovljevic
YR 2018
UL http://heart.bmj.com/content/104/2/111.abstract
AB Objective Diminished cardiac high-energy phosphate metabolism (phosphocreatine-to-ATP (PCr:ATP) ratio) and cardiac power with age may play an important roles in development of cardiac dysfunction and heart failure. The study defines the impact of age on PCr:ATP ratio and cardiac power and their relationship.Methods Thirty-five healthy women (young≤50 years, n=20; and old≥60 years, n=15) underwent cardiac MRI with 31P spectroscopy to assess PCr:ATP ratio and performed maximal graded cardiopulmonary exercise testing with simultaneous gas-exchange and central haemodynamic measurements. Peak cardiac power output, as the best measure of pumping capability and performance of the heart, was calculated as the product of peak exercise cardiac output and mean arterial blood pressure.Results PCr:ATP ratio was significantly lower in old compared with young age group (1.92±0.48 vs 2.29±0.55, p=0.03), as were peak cardiac power output (3.35±0.73 vs 4.14±0.81W, p=0.01), diastolic function (ie, early-to-late diastolic filling ratio, 1.33±0.54 vs 3.07±1.84, p<0.01) and peak exercise oxygen consumption (1382.9±255.0 vs 1940.3±434.4 mL/min, p<0.01). Further analysis revealed that PCr:ATP ratio shows a significant positive relationship with early-to-late diastolic filling ratio (r=0.46, p=0.02), peak cardiac power output (r=0.44, p=0.02) and peak oxygen consumption (r=0.51, p=0.01).Conclusions High-energy phosphate metabolism and peak power of the heart decline with age. Significant positive relationship between PCr:ATP ratio, early-to-late diastolic filling ratio and peak cardiac power output suggests that cardiac high-energy phosphate metabolism may be an important determinant of cardiac function and performance.