Dietary lipid modulation of ventricular fibrillation threshold in the marmoset monkey.
Programmed electrical stimulation was used to examine the ability of long-term dietary lipid modulation to influence myocardial vulnerability to the induction of ventricular fibrillation in adult marmoset monkeys (Callithrix jacchus). Marmosets fed diets supplemented (to a total of 28.5% of the energy as fat) with polyunsaturated fatty acid (PUFA)-rich tuna fish oil or sunflower seed oil had significantly elevated mean ventricular fibrillation threshold compared with those fed a saturated animal fat supplemented diet or a reference diet not supplemented with fat (11.2% of the energy as fat). Fibrillation threshold was reduced during acute myocardial ischemia induced by coronary artery occlusion but still remained higher in the PUFA-fed animals than either the control or the ischemic threshold in reference or saturated fat supplemented animals. Dietary tuna fish oil was associated with a low incidence of sustained fibrillation episodes and no fatalities. These results indicate that myocardial substrate vulnerability to arrhythmic stimuli is increased during ischemia in a nonhuman primate model but dietary PUFA can reduce vulnerability under both normal and ischemic conditions. Reduced dietary fat intake alone was without effect.
McLennan
P L
PL
Cardiac Research Unit, C.S.I.R.O. Division of Human Nutrition, O'Halloran Hill, Australia.
Bridle
T M
TM
Abeywardena
M Y
MY
Charnock
J S
JS
D000818:Animals; D002144:Callithrix; D002304:Cardiac Pacing, Artificial; D003327:Coronary Disease / Q000503:physiopathology; D004041:Dietary Fats / Q000494:pharmacology*; D004056:Differential Threshold; D004562:Electrocardiography; D007545:Isoproterenol / Q000494:pharmacology; D014693:Ventricular Fibrillation / Q000503:physiopathology*
D004041:Dietary Fats; D007545:Isoproterenol