Ultrasound Evaluation of the Change in Diameter of the Posterior Tibial Artery and Dorsalis Pedis Artery After the Administration of Topical Nitroglycerin.

This will be a prospective, randomized, blinded, placebo-controlled study to gather data on the effect of nitroglycerin on the pedal artery of patients with varying comorbidities. Patients will be divided into a treatment group and a control group. A detailed history will be taken from the patient to ascertain risk factors such as Hypertension, Hyperlipidemia, CAD, PAD, Tobacco abuse, Diabetes Mellitus, Family history of CAD/PAD, or history of non-healing wounds. Further demographic data such as sex, age, height, weight, body surface area, and body mass index will be documented.

Ultrasound measurements of the dorsalis pedis and anterior tibial artery will be obtained at baseline. Measurements will be obtained in the perpendicular plane using B mode on the vascular ultrasound. The largest diameter will be documented. Measurement of the largest intima diameter will be obtainedThe image will be temporarily stored for measurement purposes but will not be saved. The patients will then have differing treatments based on their groupings into the control or treatments arms.

Patient history, demographics and artery measurements will be kept on a password protected document and assigned a research patient identifier number. Another password protected document will contain the patient's name and patient identifier number. Only the principal investigator and sub-principal investigators will have access to these documents.

Patients in the control group will have measurements of their posterior tibial artery or dorsalis pedis artery bilaterally. The sites of evaluation will be marked with a surgical marker. A topical moisturizer will be placed 1 cm proximal to the measured areas of the leg and covered with a dressing bilaterally. Measurements of the arteries will be made at baseline, 10 minutes, 30 minutes, 60 minutes, and 90 minutes. In addition, non-invasive Blood Pressure measurements will be made at baseline, 10 minutes, 30 minutes, 60 minutes, and 90 minutes. The Moisturizer will be removed at 60 minutes bilaterally.

Patients in the treatment group will again receive measurements of the posterior tibial and dorsalis pedis arteries bilaterally which will be marked with a surgical marker. Randomly, the tibial artery or dorsalis artery will be selected and nitroglycerin paste will be placed 1 cm proximal to the measured area of one leg and moisturizer will be placed on the other leg in order create uniformity. Both legs will be covered with a dressing. These patients will randomly receive 15mg or 30mg of nitroglycerin. Bilateral measurements of the posterior tibial and dorsalis pedis arteries will be made at baseline, 10 minutes, 30 minutes, and 60 minutes, 90 minutes. In addition, non-invasive Blood Pressure measurements will be made at baseline, 10 minutes, 30 minutes, 60 minutes, and 90 minutes in the arm. The Moisturizer and nitroglycerin will be removed at 60 minutes.