Relation between blood and atrial fatty acids in patients undergoing cardiac bypass surgery.
BACKGROUND
Studies relating cardiovascular outcomes to dietary or blood measures of various fatty acids rely on the implicit assumptions that dietary change results in changes in blood fatty acids that, in turn, alter cardiac fatty acids. Although dietary intakes of n-3 (omega-3), n-6 (omega-6), and trans fatty acids are reflected in their concentrations in blood, there are few human data on the relation between blood and cardiac concentrations of fatty acids.


OBJECTIVE
The objective was to explore relations between blood and myocardial n-3, n-6, trans, monosaturated, and saturated fatty acids over a range of community intakes to evaluate whether blood fatty acids are useful surrogate markers of their cardiac counterparts.


METHODS
Patients undergoing on-pump coronary bypass surgery were recruited. Right atrial appendages and blood were collected at surgery for fatty acid analysis.


RESULTS
Atrial appendages and matching blood samples were collected from 61 patients. Highly significant correlations were identified between atrial and erythrocyte or plasma n-3 [eg, eicosapentaenoic acid (erythrocytes: r = 0.93, P < 0.0001; plasma: r = 0.87, P < 0.0001)], some n-6 [eg, arachidonic acid (erythrocytes: r = 0.45, P = 0.0003; plasma: r = 0.39, P = 0.002)], trans [eg, total trans 18:1 (erythrocytes: r = 0.89, P < 0.0001; plasma: r = 0.74, P < 0.0001)], and monounsaturated [eg, oleic acid (erythrocytes: r = 0.37, P = 0.003)] fatty acids. There were no statistical associations between blood and cardiac saturated fatty acids.


CONCLUSIONS
Erythrocyte- and plasma phospholipid-derived fatty acids can be used to estimate cardiac fatty acid status in humans.
Metcalf
Robert G
RG
Royal Adelaide Hospital, Adelaide, Australia. robert.metcalf@health.sa.gov.au
Cleland
Leslie G
LG
Gibson
Robert A
RA
Roberts-Thomson
Kurt C
KC
Edwards
James Rm
JR
Sanders
Prashanthan
P
Stuklis
Robert
R
James
Michael J
MJ
Young
Glenn D
GD
D000368:Aged; D020517:Atrial Appendage / Q000378:metabolism*; D015415:Biomarkers / Q000097:blood; D001026:Coronary Artery Bypass; D004032:Diet; D004041:Dietary Fats / Q000097:blood* / Q000378:metabolism; D004912:Erythrocytes / Q000378:metabolism; D005227:Fatty Acids / Q000097:blood* / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism; D009752:Nutritional Status; D012044:Regression Analysis; D015203:Reproducibility of Results
D015415:Biomarkers; D004041:Dietary Fats; D005227:Fatty Acids