The radial artery, which is located on the outer side of the forearm, can be used in
interventional procedures, such as cardiac catheterization, to provide access to the
arterial blood supply. In order to facilitate successful catheterization of the artery, a
dilated artery and one free of arterial spasm is desirable. The proposed study will
randomize twenty three healthy subjects to determine the effect of topical nitroglycerin on
radial artery vasodilation. In the first phase of the study, which is a dose escalation
study, each subject will receive either one or two inches of nitroglycerin in a blinded
manner on one wrist and placebo on the other. Radial artery diameter will be measured with
ultrasound at regular intervals up to two hours. The subjects will then return at a later
date at which point they will receive the alternate dose on one wrist and placebo on the
other. In the second phase of the study, we will randomize the same patients to a mixture of
topical nitroglycerin and lidocaine or topical lidocaine alone. Measurements of radial
artery diameter will be performed as in the first study.
- Willing and able to give written informed consent and comply with study requirements
- Patient who speak English
- Presence or history of liver, cardiovascular, rheumatologic, cancer or renal disease.
- Current treatment with any vasodilator therapy
- Systolic blood pressure of less than 90 mmHg
- History of radial artery catheterization within the previous year
- Absence of radial artery blood flow in one or both arms
- Active infection
- Staff members of the Cardiac Catheterization Laboratory.