Anti-gravity Treadmill Exercise in Stress Myocardial Perfusion Imaging
Coronary Artery Disease
About this trial
This is an interventional diagnostic trial for Coronary Artery Disease focused on measuring antigravity treadmill, bruce protocol, stress myocardial perfusion imaging, single photon emission computed tomography, cardiac catheterization, [E01.370.370.380.500], [E01.370.370.380.250], [E01.370.370.380.140]
Eligibility Criteria
Inclusion Criteria:
- Patients >18 years of age who are able to ambulate.
- Women will either have a negative pregnancy test, be post-menopausal or have prior surgical infertility
- Nuclear stress SPECT imaging test ordered as exercise SPECT or regadenoson SPECT.
- If ordered for exercise SPECT, self-admission of inability to exercise on conventional treadmill. This typically includes subjects unable to exercise due to obesity, musculoskeletal disease, peripheral vascular disease, weakness or debilitation.
- Patients that initially start conventional treadmill exercise protocol and have to stop due to exercise-limiting symptoms including musculoskeletal pain and fatigue.
- Hemodynamically stable patients as defined by mean blood pressure (BP) >75 mm Hg and heart rate (HR) 60-120 beats per minute.
Exclusion Criteria:
- Hemodynamically unstable patients as defined by resting mean BP <75 and HR <60 or >120.
- Patients with acute coronary syndrome as defined by troponin elevation (>0.05) within the past 72 hours.
- Patients at high clinical risk related to severe aortic stenosis, known exercise-induced ventricular tachycardia or fibrillation, or advanced (second-degree type II or third-degree) heart block.
- Patients with left bundle branch block or paced cardiac rhythm (in whom exercise is associated with non-ischemic perfusion abnormalities).
- Patients unable to provide consent or unable to cooperate.
- Inability to physically enter onto the anti-gravity treadmill unit.
- Pregnant women.
- Patients with a contraindication to receive regadenoson (sinus node dysfunction, high-degree heart block, active wheezing/reactive airway disease).
- At risk patient populations (prisoners or severely mentally handicapped).
Sites / Locations
- University of Cincinnati Medical Center
Arms of the Study
Arm 1
Arm 2
Experimental
Active Comparator
Test arm
Control arm
The subjects randomized to the anti-gravity treadmill arm will be instructed on the safe use of the Alter-G treadmill by the study staff. After this instruction, subjects will be exercised on the Alter-G anti-gravity treadmill using the conventional Bruce protocol with unweighting to 75% of their body weight to reach target heart rate. If the subject is unable to reach the target heart rate, they will be further unweighted to 50% of their body weight to enable the subject to reach target heart rate on the Bruce protocol. If the subject is still unable to reach target heart rate with 50% unweighting, the patient's subsequent SPECT images will be excluded from use in the research comparison to control subject images.
The control arm subjects will undergo the conventional treadmill/regadenoson pharmacological stress SPECT. Consistent with standard practice, these patients will perform adjunctive low-intensity walk on a conventional treadmill prior to regadenoson and Tc-99m injection if tolerated.