Optimal starting time of acquisition and feasibility of complementary administration of nitroglycerin with intravenous beta-blocker in multislice computed tomography.
OBJECTIVE
We determined the optimal starting time of acquisition after sublingual nitroglycerin (NTG) administration and evaluated the effects on multislice computed tomographic (MSCT) images of a complementary administration of sublingual NTG with beta-blocker.


METHODS
Sixty patients who underwent MSCT coronary angiography (CA) were randomly divided into 2 groups as follows: 30 patients given an intravenous administration of beta-blocker (landiolol hydrochloride, mean dose of 0.032 mg/kg per minute; group B); and 30 patients given a coadministration of intravenous beta-blocker and sublingual NTG (0.3 mg; group N). Blood pressure and heart rate were recorded every 1 minute after NTG administration. In addition, the maximum diameters of the proximal and distal lesions in each coronary artery were measured, and the number of assessable segments was calculated.


RESULTS
Blood pressure significantly decreased and heart rate significantly increased 4 minutes after NTG administration. The number of assessable segments was significantly greater in group N than in group B. The maximum diameters of the distal lesions of the left anterior descending and left circumflex arteries and both proximal and distal lesions of the right coronary artery were significantly larger in group N than in group B.


CONCLUSIONS
It is advisable to obtain MSCT images after sublingual NTG administration because nitrates are always given during conventional CA and may prevent beta-blocker-induced coronary spasm. The optimal starting time for MSCT CA is approximately 3 minutes after sublingual NTG administration.
Division of Radiology, Kami-iida Daiichi General Hospital, Nagoya University Graduate School of Medicine, Nagoya, Japan.
Kimihide
K
Sato
Satoshi
S
Isobe
Kaichiro
K
Sugiura
Takeo
T
Mimura
Yukari
Y
Yotsudake
Chizuka
C
Meno
Makoto
M
Kato
Ken
K
Harada
Toyoaki
T
Murohara
D000286:Administration, Sublingual; D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage* / Q000009:adverse effects; D000368:Aged; D001794:Blood Pressure / Q000187:drug effects; D017023:Coronary Angiography / Q000379:methods*; D023921:Coronary Stenosis / Q000139:chemically induced / Q000517:prevention & control; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D005240:Feasibility Studies; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D005996:Nitroglycerin / Q000008:administration & dosage*; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014665:Vasodilator Agents / Q000008:administration & dosage
D000319:Adrenergic beta-Antagonists; D014665:Vasodilator Agents; D005996:Nitroglycerin