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Completed

NCT Number: NCT03170817

Quantitative 13N-Ammonia Cardiac Rest/Stress Digital PET/CT

Accurate measurements from a non-invasive test like myocardial perfusion positron emission tomography/ computed tomography (PET/CT) may decrease the need for invasive procedures such as cardiac catheterization.The investigators wish to see if the measurements from cardiac catheterization can be predicted using a non-invasive 13N-NH3 digital PET/CT scan.

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Key information

Conditions

Coronary Artery Disease Arterial Occlusive Diseases Arteriosclerosis Cardiovascular Diseases Coronary Disease Heart Diseases Myocardial Ischemia Vascular Diseases

Age range

18 year and older

Sex eligibility

All sexes

Study type

Observational

Primary location

Stanford University

Stanford, California, 94305, United States

About this study

Cardiac imaging using standard-of-care Nuclear Medicine techniques assess the relative radiopharmaceutical distribution from coronary arteries to cardiac tissue. This standard interpretation however, lacks the clinical utility of modern quantitative techniques that are now routinely obtained during cardiac catheterization, such as fractional flow reserve (FFR). Cardiologists routinely base critical management decisions, including the choice for revascularization, stenting, or angioplasty, on these measurements.

Non-invasive measurements of MBF (Myocardial Blood Flow), CFR (Coronary Flow Reserve) and RFR (Relative Flow Reserve) using PET/CT have been investigated, but have yet to reach clinicl use. Given the inherent gains in sensitivity and resolution, digital PET/CT, may allow for a more robust and accurate platform to obtain quantitative measurements of MBF, CFR and RFR which may greatly enhance the clinical utility of cardiac PET/CT for management of coronary artery disease.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Patient is ≥ 18 years old at the time of the scan
  • Patient has known or suspected coronary artery disease
  • Patient has had a recent or will be scheduled for a diagnostic coronary angiogram
  • Patient provides written informed consent
  • Patient is referred for myocardial perfusion scan
  • Patient is capable of complying with study procedures
  • Patient is able to remain still for duration of imaging procedure (approximately 60 minutes total for both PET/CT)

Exclusion criteria

  • Patients who are pregnant or breast feeding
  • Patients with contraindications to regadenoson

Treatment and study plan

Cardiac Perfusion Rest/Stress Digital PET/CT

Diagnostic Test

Patients with coronary artery disease undergo a N-13 ammonia rest/stress PET/CT scan.

These patients are given:

  • One 5-10 mCI N13-ammonia (13N-NH3) intravenously and undergo a rest digital PET/CT scan of ~20 minute duration.
  • A dose of 0.4 mg regadenoson (Lexiscan) intravenously over 10 seconds to increase blood flow to the heart
  • One 5-10 mCi N13-ammonia (13N-NH3) intravenously and undergo a stress digital PET/CT scan of ~20 minute duration

Total patient time will take approximately up to 120 minutes.

N-13 ammonia

Drug

5-10 mCi intravenous injection of N-13 ammonia radiopharmaceutical at rest and at stress

Regadenoson

Drug

0.4 mg/5mL intravenous injection to induce pharmacologic stress (Astellas Pharma US, Inc.)

Other names: Lexiscan

Primary outcomes

  1. MBF measurement using PET/CT

    Time frame: an estimated average of 2 hours

    Non-invasive measurements of myocardial blood flow (MBF) in milliliter/minute/gram using PET/CT scanner will be compared to invasive cardiac angiography values (current gold standard). MBF values are obtained using image-derived time activity curves from the left ventricular blood and myocardial tissue regions. These values represent radiotracer exchange between the blood and the tissue over time. The rate of radiotracer uptake into the myocardial tissue provides an estimate of MBF. Processing software will then use the time-activity curves to calculate MBF at rest and at stress.

  2. CFR measurement using PET/CT

    Time frame: an estimated average of 2 hours

    Non-invasive measurements of coronary flow reserve (CFR) using digital PET/CT scanner will be compared to the gold standard evaluation from invasive cardiac angiography. Discrepancy between PET measurements and cardiac angiography results will be reported. CFR is the ratio of MBF at peak blood flow to resting MBF.

  3. RFR measurement using PET/CT

    Time frame: an estimated average of 2 hours

    Non-invasive measurements of relative flow reserve (RFR) using digital PET/CT scanner will be compared to the gold standard evaluation from invasive cardiac angiography. Discrepancy between PET measurements and cardiac angiography results will be reported. RFR is the ratio of MBF during stress in an affected region of the left ventricle (LV) to MBF during stress in a normal region of the LV.

Secondary outcomes

  1. NM Physician diagnostic confidence of 13N-NH3 PET/CT

    Time frame: an estimated average of 2 hours

    Nuclear medicine physician diagnostic confidence will be assessed using a 5-point Likert scale. NM Physicians will compare images obtained from the 13N-NH3 PET/CT to images obtained from single photon emission computed tomography/CT (SPECT/CT).

  2. Overall Exam Time

    Time frame: an estimated average of 2 hours

    Overall study time as counted from initial administration of radiopharmaceutical to completion of image acquisition will be measured and compared to SPECT/CT overall exam time.

  3. Effective radiation dose

    Time frame: an estimated average of 2 hours

    Total radiation dose (measured in mSv) from 13N-NH3 PET/CT will be measured and compared to the dose typically given to patients during standard myocardial perfusion imaging SPECT/CT studies.

Sponsors and collaborators

Lead sponsor

Stanford University

Other

Collaborators

  • GE Healthcare

Registry information

Official study title

Quantitative Rest/Stress Cardiac Perfusion Digital PET/CT: Comparison Between Noninvasive Imaging and Invasive Coronary Angiography.

Important dates

Study start
2017
Primary completion
2020
Study completion
2021
First posted
May 31, 2017
Registry last updated
Oct 26, 2021

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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