Direct relationship between ischaemic burden and myocardial release of products of lipid peroxidation in patients undergoing percutaneous transluminal coronary angioplasty.
BACKGROUND
Recent studies have shown that free radical activity is increased in humans during percutaneous transluminal coronary angioplasty. These studies, however, have failed to localize the site of free radical activity or to demonstrate a relationship between ischaemic burden and free radical production.


METHODS
The relationship between ischaemic burden and subsequent lipid peroxidation was studied during 16 inflations in eight patients undergoing angioplasty to anterior descending artery lesions. Two inflations 15 min apart were studied in each patient, one using a conventional (occlusive) balloon and one using the ACS Rx 'perfusion' balloon. The severity of the ischaemic insult associated with each inflation was assessed by contrast ventriculography, change in left ventricular end-diastolic pressure and myocardial lactate release 30 s after balloon deflation. Plasma levels of lipid peroxidation products were assessed by analysis of thiobarbituric-acid-reactive substances.


RESULTS
A direct relationship was observed between the ischaemic burden and the myocardial release of lipid peroxidation products over the first 4 min after balloon deflation (F = 5.6; P < 0.006). In each patient, one of the inflations was associated with a greater degree of ischaemia. Left ventricular ejection fraction was lower (P < 0.001) and left ventricular end-diastolic pressure was higher (P < 0.002) during the 'ischaemic' inflations. Myocardial release of lipid peroxidation products was significantly higher after the 'ischaemic' balloon inflation (F = 7.65; P < 0.009).


CONCLUSIONS
Brief periods of human myocardial ischaemia result in myocardial release of lipid peroxidation products in direct proportion to the severity of the preceding ischaemic insult.
Coghlan
J G
JG
Department of Cardiology, Harefield Hospital, UK.
Flitter
W D
WD
Paul
V E
VE
Mitchell
A G
AG
Slater
T F
TF
Ilsley
C D
CD
D000368:Aged; D000369:Aged, 80 and over; D015906:Angioplasty, Balloon, Coronary; D003327:Coronary Disease / Q000503:physiopathology* / Q000628:therapy*; D005260:Female; D006801:Humans; D015227:Lipid Peroxidation / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D015428:Myocardial Reperfusion Injury / Q000503:physiopathology*; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis; D016277:Ventricular Function, Left; D014810:Vitamin E / Q000097:blood
D017392:Thiobarbituric Acid Reactive Substances; D014810:Vitamin E