Integrated Dual Exercise and Lexiscan Positron Emission Tomography: IDEALPET

Phase 4

Completed

Interventions: Drug: Exercise plus Regadenoson (Lexercise)
Drug: Regadenoson (Lexiscan)

Brief Summary: This is a single-center study of subjects undergoing clinically indicated heart scans for evaluation of known or suspected heart disease. We will also include 10 healthy subjects without known heart disease. We would like to study stress testing of the heart using exercise and a medication called regadenoson. Imaging of the heart will be performed.

Detailed Description: Regadenoson is stress agent approved by the FDA for use with myocardial perfusion imaging with technetium-99m single photon emission computed tomography (SPECT) in patients that are unable to exercise adequately. We would like to study Regadenoson in conjunction with Exercise Rubidium-82 positron emission tomography myocardial perfusion imaging (PET MPI). Regadenoson is not approved by FDA for use with Rubidium-82 PET MPI. Also, we would like to study a novel stress protocol of Regadenoson combined with symptom limited exercise stress (not FDA approved).

The objectives of this study are to assess the tolerability and safety of combined symptom limited exercise stress test with Lexiscan (Lexercise PET) compared to Lexiscan alone (Lexiscan PET), to assess image quality of Lexercise compared to Lexiscan PET and to compare relative and absolute myocardial perfusion imaging with Lexercise compared to Lexiscan PET to identify CAD.

Recruitment & Eligibility

Inclusion Criteria

Age > 18 years
Clinically indicated N-13 ammonia PET study or ten healthy volunteers
Known coronary artery disease (prior percutaneous coronary intervention, prior coronary artery bypass surgery or Q wave MI on ECG) or intermediate to high pretest likelihood of CAD
Able to exercise on a treadmill
Able and willing to provide informed consent to participate in the study

Exclusion Criteria

Contraindications to exercise stress testing such as, unstable angina, known severe left main coronary artery stenosis, severe heart failure, uncontrolled arrhythmias, symptomatic hypotension or severe hypertension (systolic blood pressure < 90 or > 200 mmHg, respectively), or > 1st degree atrioventricular block in the absence of a functioning pacemaker.
Subject requires emergent cardiac medical intervention or catheterization after the clinical study.
Documented myocardial infarction (MI) ≤ 30 days prior to enrollment.
History of percutaneous coronary intervention (PCI) ≤ 4weeks prior to enrollment.
History of coronary artery bypass graft (CABG) ≤ 8 weeks prior to enrollment.
History of heart transplantation.
Allergy or intolerance to aminophylline or regadenoson
Known severe or oxygen dependent bronchoconstrictive or bronchospastic lung disease [e.g., asthma, wheezing, chronic obstructive pulmonary disease (COPD), etc.].
Severe LV dysfunction, with ejection fraction of < 30%
Serious non-cardiac medical illness (e.g., disseminated malignancy, severe neurological dysfunction at time of baseline PET study) or a social situation which will preclude research study participation
History of Seizures.

Arm && Interventions

Group	Intervention	Description
Exercise + Regadenoson (Lexercise)	Exercise plus Regadenoson (Lexercise)	Exercise plus Regadenoson (Lexercise) Rubidium-82 Positron Emission Tomography
Regadenoson (Lexiscan)	Regadenoson (Lexiscan)	Regadenoson Rubidium-82 Positron Emission Tomography

Primary Outcome Measures

Name	Time	Method
Safety and Tolerability of Combined Exercise and Regadenoson Stress	Day of the research scan during the stress test	1. Count of subjects with ischemic ECG changes is reported 2. Count of subjects with systolic blood pressure decrease \> 20 mm Hg is reported 3. Count of subjects with abnormal serum troponin T levels is reported 4. Radiation dose to the staff will be measured using personal dosimeters after the Lexiscan as well as the Lexercise PET study.

Secondary Outcome Measures

Name	Time	Method
Changes in Left Ventricular Function With Dual Exercise and Regadenoson PET	Week 1 (day of the clinical scan), and Week 2 (day of the research scan)	Left ventricular ejection fraction (LVEF) at stress was measured at Stress scan 1 (regadenoson) and Stress scan 2 (regadenoson or exercise + regadenoson). This was measured on the clinical scan and on the research scan which were performed about 2 weeks apart in most subjects.
Image Quality: Heart to Liver Ratio of Counts	Week 1 (day of the clinical scan), and Week 2 (day of the research scan)	Sub-diaphragmatic activity: Heart to Liver Ratio was measured on the rubidium-82 and N-13 ammonia scans. Since this measure is a ratio it has no units. Mean and Standard Deviation of Ratio is reported for each group. This was measured on the clinical scan and on the research scan which were performed about 2 weeks apart in most subjects.
Peak Stress Myocardial Blood Flow	Week 1 (day of the clinical scan), and Week 2 (day of the research scan)	Myocardial Blood Flow Measured at Peak Hyperemia With Regadenoson or Immediately After Exercise + Regadenoson This was measured on the clinical scan and on the research scan which were performed about 2 weeks apart in most subjects.