Comparison of Rubidium PET and SPECT With CZT Crystals for Detection of Myocardial Ischemia in Overweighed Patients and Women (RUBIS)

• Myocardial ischemia [ Time Frame: 1 year ] [ Designated as safety issue: No ]

  Patients will be classified as positive in case of:

  • Coronary stenosis ≥ 50 % on coronary angiography and fractional flow reserve < 0.8, or, in absence of FFR, a critical coronary stenosis.
  • In absence of coronary angiography, presence of cardiovascular event during the following year.
  
  

• Size and intensity of myocardial ischemia [ Time Frame: 1 year ] [ Designated as safety issue: No ]
  1. Size and intensity of myocardial ischemia quantified using the sum difference score,
  2. Left ventricular function at stress and at rest
  3. Values of FFR measured invasively and noninvasively
  4. Effective dose caused by radiation exposure
  5. Costs of the two diagnostic strategies
  
  

The main objective of this study will be to compare the diagnostic performances of 82Rubidium-PET associated to pharmacologic stress (Persantine) to 99mTc-Sestamibi-SPECT with CZT cameras associated to a stress test (exercise, pharmacological, mixed) for detection of myocardial ischemia in a population of overweighed patients on one hand, and women on the other hand, in a population with an intermediate prevalence of coronary artery disease (≥ 3 cardiovascular risk factors in asymptomatic patients or prevalence of CAD ≥ 30 % using the DIAMOND-FORRESTER score in symptomatic patients).

Secondary objectives. (1) Comparison between the size and intensity of myocardial ischemia quantified using the sum difference score, left ventricular function at stress and at rest, measured with 99mTc-Sestamibi-SPECT with CZT cameras and 82Rubidium-PET.

(2) Comparison between the values of coronary fractional flow reserve measured invasively and noninvasively with 82Rubidium-PET in patients with stenosis ≥ 50 % on coronary angiography.

(3) Comparison of the effective dose caused by radiation exposure with 99mTc-Sestamibi-SPECT with CZT cameras and 82Rubidium-PET.

(4) Comparison of the costs of the two diagnostic strategies in this population of patients.

Inclusion criteria: Overweighed (body mass index ≥ 25) or women addressed in the Department of Nuclear Medicine for diagnostic cardiac scintigraphy with an intermediate pre-test prevalence of CAD (≥ 3 cardiovascular risk factors in asymptomatic patients or prevalence of CAD ≥ 30 % using the DIAMOND-FORRESTER score in symptomatic patients).

Non-inclusion criteria: Pregnant women; contraindication to dipyridamole injection.

Number of patients: 261 patients

Duration of the study. Duration of the study for a patient will be 12 months. Total duration of the study will be 20 months, including an 8-month inclusion time period.

Primary endpoint: Patients will be classified as positive in case of:

• Myocardial ischemia defined as the presence of coronary stenosis ≥ 50 % on coronary angiography with functional impairment of blood flow confirmed by invasive measurement of coronary flow reserve (fractional flow reserve, FFR < 0.8), or, in absence of measurement of FFR, a critical coronary stenosis confirmed by the validation committee of coronary angiographies.
• In absence of coronary angiography, the presence of cardiovascular event (cardiovascular or unknown cause of death, admission for acute coronary syndrome, unstable angina, myocardial ischemia or coronary revascularization) validated by the endpoint adjudication committee in the year following inclusion of the patient in the study.

Secondary endpoints: (1) Size and intensity of myocardial ischemia quantified using the sum difference score and, left ventricular function at stress and at rest, measured with 99mTc-Sestamibi-SPECT with CZT cameras and 82Rubidium-PET. (2) Values of coronary fractional flow reserve measured invasively and noninvasively with 82Rubidium-PET in patients with stenosis ≥ 50 % on coronary angiography. (3) Effective dose caused by radiation exposure with 99mTc-Sestamibi-SPECT with CZT cameras and 82Rubidium-PET. (4) Costs of the two diagnostic strategies in this population of patients.