Peripheral Arterial Disease
Conditions
Brief summary
Our laboratory has discovered that ultrasound (US) imaging together with clinically approved microbubble ultrasound contrast agents can augment limb tissue perfusion. These observations have been made in mice with and without peripheral artery disease (PAD), and also in humans where high power contrast enhanced ultrasound (CEU) was used to measure perfusion but was found also to augment perfusion by almost 2-fold. The latter human studies were performed with ultrasound protocols designed for perfusion imaging and not for flow augmentation. In this study, we will measure the degree to which limb perfusion is augmented with specific therapeutic CEU settings that are still within the FDA-approved limits with regards to US power and contrast dosing.
Interventions
Ultrasound exposure of Definity microbubbles infused over 10 min. Ultrasound administered at 1.3 MHz, mechanical index of 1.3, and pulsing interval of 10 s.
Sponsors
Study design
Eligibility
Inclusion criteria
* Age ≥18 y.o. * For PAD subjects: known history of unilateral or bilateral PAD diagnosed by reduced ankle-brachial index or angiography and a Rutherford symptom class of 4-6.
Exclusion criteria
1. Major medical illness other than PAD affecting the limb (muscle disease, blood diseases that influence flow or rheology, severe heart failure \[NYHA class IV or LVEF \<30%\]). 2. Pregnant or lactating females 3. Hypersensitivity to any ultrasound contrast agent 4. Known atrial septal defect or large right to left shunt. 5. Hemodynamic instability (hypotension with systolic BP \<90 mm Hg, need for vasopressors) 6. Evidence for ongoing myocardial ischemia 7. For normal controls, any known structural non-arrhythmic cardiovascular disease (coronary artery disease, heart failure, moderate or greater valve disease).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in blood flow at 10 min | 10 min post-therapeutic ultrasound cavitation. | Change in blood flow in calf skeletal muscle |
| Change in blood flow at 60 min | 60 min post-therapeutic ultrasound cavitation | Change in blood flow in calf skeletal muscle |
Countries
United States