Evaluation of the Functional Impact of Coronary Stenoses in Diabetics by Spectral CT
Overview
- Phase
- Not Applicable
- Intervention
- dual-energy dual-layer spectral scanner
- Conditions
- Coronary Stenosis
- Sponsor
- Hospices Civils de Lyon
- Enrollment
- 150
- Locations
- 1
- Primary Endpoint
- Identification of tight coronary stenoses justifying coronary angiography
- Status
- Not yet recruiting
- Last Updated
- 3 years ago
Overview
Brief Summary
The optimal screening methods for coronary insufficiency, a frequent and pejorative complication in diabetics, are subject to debate, particularly in situations of silent myocardial ischemia. The contemporary strategy consists of pre-selecting asymptomatic patients at very high cardiovascular (CV) risk by performing a coronary calcium score. If this is found to be high >300 AU (Agatston units), the patient is suspected of being at high risk of silent myocardial ischemia (SMI), and the assessment is completed to exclude the presence of coronary artery disease likely to benefit from revascularization.
The complementary evaluation consists in evaluating the myocardial perfusion to judge the perfusion repercussions. The most common examination to date is myocardial scintigraphy, because stress tests are too frequently submaximal in diabetics. However, the reproducibility of scintigraphy is controversial and their sensitivity and specificity are debated in this indication.
This problem is similar in stable symptomatic coronary diabetic patients for whom an indication for functional examinations is justified.
The double-energy double-layer spectral scanner (SDEDC) could now become a relevant tool in this field, since it can combine not only anatomical data (identification of coronary stenosis) but also functional data (myocardial perfusion) during a stress protocol. thanks to the spectral images which make it possible to measure the tissue concentration of intramyocardial iodine downstream of the considered stenosis.
Investigators
Eligibility Criteria
Inclusion Criteria
- •Aged man ≥50 years old or woman aged ≥55 years old, (age difference justified for established menopause which increases the CV risk and to avoid the risk of CT scan during pregnancy)
- •Diabetic (type 1 or type 2 or type 3):
- •Asymptomatic, falling within the scope of screening for silent myocardial ischemia and having a CAC \> 300 AU or
- •Symptomatic on the coronary level, within the framework of the evaluation of symptomatic coronary insufficiency with positive myocardial scintigraphy.
- •Patient having agreed to participate in the study and signed a written informed consent
- •Patient affiliated to a social security scheme or similar
Exclusion Criteria
- •Drug intolerance (adenosine, and/or contrast product used (Iomeron))
- •Related to iodine injection:
- •History of major immediate or delayed skin reaction + hypersensitivity to the active substance or to any of the excipients
- •Renal failure with GFR \< 45 ml/min -
- •Known autonomic goiter with risk of thyrotoxicosis
- •No suspension of the biguanide the same day of the examination (and resumed 48 hours later)
- •Linked to the injection of adenosine and regadenoson (Cf SPC Adenoscan combination with dipyridamole)
- •2nd or 3rd degree BAV not fitted, sinus dysfunction not fitted,
- •Long QT syndrome,
- •Decompensated heart failure,
Arms & Interventions
Patients with CAC ≥ 300 three years ago
Patients with CAC ≥ 300 three years ago with the need for repeat screening. Adult asymptomatic diabetic patients whose risk of ischemic complications is considered major in primary prevention due to a calcium score \>300 AU and requiring iterative screening for IMS recommended every 3 at 5 years.
Intervention: dual-energy dual-layer spectral scanner
Patients with CAC ≥ 300 three years ago
Patients with CAC ≥ 300 three years ago with the need for repeat screening. Adult asymptomatic diabetic patients whose risk of ischemic complications is considered major in primary prevention due to a calcium score \>300 AU and requiring iterative screening for IMS recommended every 3 at 5 years.
Intervention: Stress protocol with adenosin during dual-energy dual-layer spectral scanner
Patients with CAC between 200-299 three years ago
Patients with CAC between 200 and 299 three years ago, with the need for a reassessment of their cardiovascular risk. Adult asymptomatic diabetic patients whose risk of ischemic complications is considered major in primary prevention due to a calcium score that has become pathological \> 300 AU during the reassessment of their cardiovascular risk.
Intervention: dual-energy dual-layer spectral scanner
Patients with CAC between 200-299 three years ago
Patients with CAC between 200 and 299 three years ago, with the need for a reassessment of their cardiovascular risk. Adult asymptomatic diabetic patients whose risk of ischemic complications is considered major in primary prevention due to a calcium score that has become pathological \> 300 AU during the reassessment of their cardiovascular risk.
Intervention: Stress protocol with adenosin during dual-energy dual-layer spectral scanner
Patients with a recent positive scintigraphy (< three months)
Patients with a recent positive scintigraphy (\< three months) requiring coronary angiography Stable symptomatic diabetic adult patients, suspected of coronary insufficiency in whom the assessment included a positive scintigraphy with indication of coronary angiography in the perspective of revascularization.
Intervention: dual-energy dual-layer spectral scanner
Patients with a recent positive scintigraphy (< three months)
Patients with a recent positive scintigraphy (\< three months) requiring coronary angiography Stable symptomatic diabetic adult patients, suspected of coronary insufficiency in whom the assessment included a positive scintigraphy with indication of coronary angiography in the perspective of revascularization.
Intervention: Stress protocol with adenosin during dual-energy dual-layer spectral scanner
Outcomes
Primary Outcomes
Identification of tight coronary stenoses justifying coronary angiography
Time Frame: Measured at day 0
An anomaly considered significant corresponds to: * the presence of coronary stenosis \>50% with significant hypoperfusion or stenosis \> 75% by spectral CT (SDEDC) * of a significant hypoperfusion on myocardial scintigraphy (SPECT) Reading Committee: Creation of a blind review committee for myocardial SPECT scans and the SDEDC spectral scanner, without knowledge of the coronary angiography data or the other perfusion examination for statistical comparison.
Secondary Outcomes
- Identification of tight coronary stenoses justifying a coronary angiography including a measurement of the Fractional Flow Reserve (FFR)(Measured at day 0)
- Sensitivity and specificity of the study(Measured at day 0)
- Proportion of mismatches in diabetics and their predisposing factors(Measured at day 0)
- Collection of the subjective assessment of the 2 examinations (SDEDC and myocardial scintigraphy)(Measured at day 1 and 2)