Phase Analysis and Obstructive CAD on Rubidium PET

Study Overview
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Brief Summary
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Rubidium myocardial perfusion PET is an imaging test used to diagnose patients with abnormal blood flow to the heart secondary to narrowing of the heart vessels. Phase analysis is a computer method that is applied after the PET test is done. It is used to determine when a region of the heart contracts relative to other heart regions in the heart beating cycle. Initial data suggest that regions of the heart with abnormal blood flow change the pattern of contraction from rest to stress conditions. That is, regions of the heart with abnormal blood supply become dyssynchronous when compared to the normal regions of the heart. This study will investigate whether phase analysis may aid the visual interpretation of rubidium myocardial perfusion PET studies by determining the areas of the heart that are not beating in synchrony with the normal heart regions. This information will be used as a proxy for poor blood supply. The gold standard will be coronary angiography by which the percent narrowing of the heart vessels is assessed.

Official Title
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Regional and Global Left Ventricular Mechanical Dyssynchrony in the Diagnosis of Obstructive Coronary Artery Disease on Rest and Regadenoson Stress Rubidium Myocardial Perfusion PET

Conditions
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Coronary Artery Disease

Intervention / Treatment
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* Drug: Regadenoson


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Male or female patients referred for myocardial perfusion imaging for suspected obstructive CAD 18 years of age or older. Exclusion Criteria: Contraindications to regadenoson radionuclide imaging including severe reactive airway disease, unstable crescendo angina, high grade AV block, caffeine within 24 hours Documented prior myocardial infarction Severe claustrophobia Patients who may be pregnant.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Regadenoson<br> | Drug: Regadenoson<br>* Vasodilator stress testing<br>* Other names: Lexiscan;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Stress/rest differences in global left ventricular mechanical contraction bandwidth. | The investigators will measure the percent change in global left ventricular mechanical contraction bandwidth between stress and rest perfusion imaging as measured by phase analysis. Two patients were enrolled but the data were not analyzed. | Up to 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Stress/rest differences in segmental left ventricular mechanical contraction bandwidth. | The investigators will measure the percent change in segmental (each of 3 major coronary arteries) left ventricular mechanical contraction bandwidth between stress and rest perfusion imaging as measured by phase analysis. | Up to 12 months |