Coronary collaterals during single-vessel coronary angioplasty: effects of nitroglycerin.
BACKGROUND
Although the protective role of collaterals in coronary artery disease (CAD) is well known, the influence of drugs on collateral function remains controversial.


OBJECTIVE
We aimed to investigate prospectively the prevalence of spontaneously visible and recruitable coronary collaterals in consecutive patients with single-vessel CAD and the effect of systemic administration of nitroglycerin on these types of collaterals during percutaneous transluminal coronary angioplasty (PTCA).


METHODS
Ipsi- and contralateral coronary artery contrast injections were performed before and during PTCA. Simultaneously with balloon occlusion, we measured coronary artery occlusion pressure via the balloon catheter. All measurements were repeated after administration of 0.5 mg of nitroglycerin intravenously.


RESULTS
Of 101 consecutive patients, 24% had spontaneously visible and 30% had recruitable collaterals. Contralateral collaterals were five times more frequent than ipsilateral collaterals. Presence of collaterals was highly associated with the degree of coronary stenosis. Coronary occlusion pressure was higher in patients with than in those without collaterals. Collaterals prevented pain and ischemia during PTCA, and in this respect spontaneously visible collaterals were more effective than recruitable collaterals. There was no effect of systemic administration of nitroglycerin on appearance or occlusion pressure of coronary collaterals.


CONCLUSIONS
Coronary collaterals were found in more than half of patients with single-vessel CAD, as the prevalence of recruitable collaterals was slightly higher than that of spontaneously visible collaterals. Nitroglycerin did neither recruit nor augment coronary collaterals.
Department of Cardiology, Skejby University Hospital, Aarhus, Denmark.
Ulrik Hedegaard
UH
Eriksen
Torsten Toftegaard
TT
Nielsen
Henrik
H
Egeblad
Jens Peder
JP
Bagger
D000328:Adult; D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D003097:Collateral Circulation / Q000187:drug effects*; D003326:Coronary Circulation / Q000187:drug effects; D003327:Coronary Disease / Q000473:pathology; D003331:Coronary Vessels / Q000187:drug effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D005996:Nitroglycerin / Q000494:pharmacology*; D013223:Statistics as Topic; D014665:Vasodilator Agents / Q000494:pharmacology*
D014665:Vasodilator Agents; D005996:Nitroglycerin