Effects of papaverine and glycerylnitrate-verapamil solution as topical and intraluminal vasodilators for internal thoracic artery.
BACKGROUND
Arterial spasm is described as an event occurring after left internal thoracic artery (LITA) harvesting. Many vasodilators have been used to treat or prevent LITA spasm. The aim of this study is to compare the effects between glyceril-trinitrate/verapamil (GV) solution and papaverine to treat LITA spasm and to determine the best delivery method.


METHODS
One hundred consecutive ischemic patients were randomly assigned to three groups: group GV (n = 34, GV solution), group P (n = 33, papaverine), or group C (n = 33, normal saline). In each patient, pedicled LITA was harvested, thereafter sprayed with the randomized solution, and covered with a sponge. Fifteen minutes after heparin administration, LITA was distally divided; flow per minute was calculated after measuring the free flow for over 15 seconds; this is named "topical free flow." Then, the vasodilator was injected intraluminally and free flow per minute was measured; this is called "intraluminal free flow."


RESULTS
Analysis of variance was applied to detect differences among groups; paired-sample t test was used for LITA topical free flow versus intraluminal free flow within single groups. Mean LITA free flows were as follows: group GV, topical free flow = 38.6 +/- 25.2 mL/min versus intraluminal free flow = 58.8 +/- 29 mL/min (p < 0.0001); group P, topical free flow = 45.4 +/- 38.9 mL/min versus intraluminal free flow mL/min (p < 0.0001); group C, topical free flow = 31.6 +/- 19.9 mL/min versus intraluminal free flow = 34 +/- 19.8 mL/min (p = 0.14). Topical free flow difference among the three groups was not statistically significant (p = 0.1); intraluminal free flow difference was statistically significant (p = 0.001). Intraluminal free flow in group GV and in group P were higher than intraluminal free flow in group C (p = 0.004 and 0.001, respectively). Intraluminal free flow of group P was higher than that of group GV; this difference did not reach statistical significance (p = 1.00).


CONCLUSIONS
Glyceril-trinitrate/verapamil solution and papaverine are able to treat the spasm and increase the flow of the LITA, when they are used intraluminally. When used topically, these vasodilator agents do not ensure an optimal free flow.
Formica
Francesco
F
Cardiac Surgery Clinic, Department of Surgical Science and Intensive Care, University of Milan-Bicocca, San Gerardo Hospital, Monza, Milan, Italy. francesco_formica@fastwebnet.it
Ferro
Orazio
O
Brustia
Matteo
M
Corti
Fabrizio
F
Colagrande
Luisa
L
Bosisio
Enrica
E
Paolini
Giovanni
G
D000287:Administration, Topical; D000368:Aged; D001783:Blood Flow Velocity / Q000187:drug effects; D003327:Coronary Disease / Q000188:drug therapy / Q000601:surgery; D004564:Electrocoagulation; D005260:Female; D006801:Humans; D007269:Injections, Intra-Arterial; D008297:Male; D008323:Mammary Arteries / Q000187:drug effects* / Q000601:surgery; D008875:Middle Aged; D005996:Nitroglycerin / Q000008:administration & dosage* / Q000494:pharmacology / Q000627:therapeutic use; D010208:Papaverine / Q000008:administration & dosage* / Q000494:pharmacology / Q000627:therapeutic use; D012996:Solutions; D020858:Tissue and Organ Harvesting / Q000009:adverse effects* / Q000379:methods; D014661:Vasoconstriction / Q000187:drug effects*; D014665:Vasodilator Agents / Q000008:administration & dosage* / Q000494:pharmacology / Q000627:therapeutic use; D014700:Verapamil / Q000008:administration & dosage* / Q000494:pharmacology / Q000627:therapeutic use
D012996:Solutions; D014665:Vasodilator Agents; D014700:Verapamil; D010208:Papaverine; D005996:Nitroglycerin