FLOW 3 - The Association Between Catheter-based Coronary Flow and Resistance and 15O-H2O Positron Emission Tomography Scan-based Absolute Myocardial Blood Flow in the Coronary Artery Territory.
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 40
- 试验地点
- 1
- 主要终点
- The diagnostic performance of 15O-H2O PET between low and high IMR groups
研究概览
简要总结
Aims
- To assess the correlation between absolute flow and resistance assessed by catheter-based thermodilution technique using CoroFlow®-system and myocardial blood flow (MBF) measured by positron emission tomography (PET) and the tracer [15O] labeled water ([15O]H2O) (15O-H2O PET)
- To assess the correlation between impaired MBF measured with 15O-H2O PET and negative fractional flow reserve (FFR) and index of microvascular resistance (IMR) level.
Hypothesis:
In patients with angina pectoris and reduced MBF measured with 15O-H2O PET but no hemodynamic significant stenosis (FFR > 0.80), the IMR is >25 measured with continuous thermodilution indicating microcirculatory dysfunction.
Methods:
We include patients with angina pectoris and suspected coronary disease based on a cardiac-computerised tomography (CT) scan. Patients are then referred to an 15O-H2O PET (rest and stress) and then a diagnostic invasive coronary angiography (ICA) with physiological assessment.
详细描述
Background Computer tomography coronary angiography (CTCA) is a purely an anatomical scan and can be insufficient in assessing the significance of a coronary stenosis. The latest European guidelines recommend that, as a supplementary study after heart CT and before invasive coronary angiography (ICA), a myocardial perfusion study is performed to avoid unnecessary invasive procedures.
Several PET flow tracers are available, but 15O-H2O is considered the gold standard for quantification of regional myocardial perfusion since 15O-H2O is a freely diffusible tracer. 15O-water PET has been validated for measure perfusion in myocardium.
15O-H2O is an inert radiopharmaceutical of oxygen-15 (O-15) labelled water used as a tracer molecule with positron emission tomography (PET). Upon administration, 15O-H2O is freely diffusible and its distribution, as well as its clearance, are completely dependent on the rate of blood flow. 15O-H2O PET imaging is golden standard for measure tissue perfusion including myocardial perfusion. The PET agent 15O-H2O has a very short half-life of about 2 minutes thereby allowing for multiple, serial measurements. Two recent studies have described the diagnostic accuracy of 15O-H2O PET in comparison to coronary angiography.
In both studies, 15O-H2O PET had a sensitivity of 87-95%; specificity was at least 84%. The study by Danad et al7 is the largest published series to date. A recently published single-center study compared 15O-H2O PET to imaging using 99mTc and found superior performance characteristics for the 15O-H2O PET, relative to a truth standard of ICA with fractional flow reserve (FFR).
Fractional flow reserve (FFR) is defined as the maximum achievable blood flow that can still be maintained to myocardium despite the stenosis. Also described as the ratio between the pressure distal to the stenosis (Pd) and the pressure proximal (Pa) to the lesion during hyperemia.
研究设计
- 研究类型
- Interventional
- 分配方式
- Non Randomized
- 干预模型
- Parallel
- 主要目的
- Diagnostic
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Patients referred to diagnostic ICA after heart-CT
- •Able to provide an informed consent.
- •Age ≥ 18 years
排除标准
- •PCI, CABG, POBA or already acknowledge ischemic heart disease
- •Acute coronary disease or AMI
- •COPD or Asthma
- •Pregnancy and breast breeding
- •Contraindications to adenosine (severe asthma, complicated AV block, critical aortic stenosis, severe cardiac arrhythmias, severe valve diseases).
- •Renal impairment with estimated glomerular filtration rate (eGFR) <40 ml / min.
- •Allergy to X-ray contrast agents or severe metabolic disease.
- •Donor heart, mechanical heart, or mechanical heart pump
研究组 & 干预措施
Group A
FFR negative/non-significant (>0.80) and IMR negative (<25)
干预措施: Coronary Physiology (Diagnostic Test)
Group A
FFR negative/non-significant (>0.80) and IMR negative (<25)
干预措施: 15O-H2O-PET scan (Diagnostic Test)
Group B
FFR negative/non-significant (>0.80) and IMR positive (>25)
干预措施: Coronary Physiology (Diagnostic Test)
Group B
FFR negative/non-significant (>0.80) and IMR positive (>25)
干预措施: 15O-H2O-PET scan (Diagnostic Test)
结局指标
主要结局
The diagnostic performance of 15O-H2O PET between low and high IMR groups
时间窗: From the 15O-H2O PET scan to the coronary physiology assessment during ICA, up to 1 week.
positive predictive value (PPV), negative predictive value (NPV) for absolute myocardial blood flow measured by 15O-H2O PET in detection of coronary microcirculatory diseases measured by index of microcirculatory index (IMR) during catheter-based thermodilution technique.
Sensitivity, specificity for absolute myocardial blood flow measured by 15O-H2O PET in detection of coronary microcirculatory diseases measured by index of microcirculatory index (IMR)
时间窗: From the 15O-H2O PET scan to the coronary physiology assessment during ICA, up to 1 week.
Sensitivity, specificity for absolute myocardial blood flow measured by 15O-H2O PET in detection of coronary microcirculatory diseases measured by index of microcirculatory index (IMR) during catheter-based thermodilution technique. The diagnostic performance of 15O-H2O PET between low and high IMR groups
次要结局
未报告次要终点
研究者
Evald Hoej Christiansen
Clinical Associate Professor
Aarhus University Hospital Skejby