The proposed study is to validate a new non-invasive imaging technique for evaluation of cardiac microciculation in coronary artery disease with a comparison with validated technique invasive, which is measure of index of myocardial resistance.
Coronary microvascular dysfunction is closely associated with coronary artery disease, it is an independent risk factor and predicts future coronary events or clinically manifest disease up to 10 years later. Index of microcirculatory resistance (IMR) is a validated method to Assessment of the Coronary Microcirculation but this is an invasive technique. In this study, we use a new mathematic technique from homogeneity analysis to provide precise, objective, automated quantification of perfusion heterogeneity at stress with new camera CZT SPECT. We compare the results with those of the measurement of IMR.
Study Type
INTERVENTIONAL
Allocation
NA
Purpose
DIAGNOSTIC
Masking
NONE
Enrollment
45
a new non-invasive imaging technique for evaluation of cardiac microciculation in coronary artery disease
University Hospital of Grenoble
Grenoble, Isère, France
coronary microcirculation
IMR was measured with commercially available software (St Jude Medical Systems) and thermodilution technique on a non-ischemic artery SPECT. Injections of 3 mL of room-temperature saline were made down the coronary artery, and the resting mean transit time (Tmn) was measured. CFR was calculated as resting Tmn divided by hyperemic Tmn. FFR was calculated by the ratio of Pd/Pa at maximal hyperemia.IMR was defined as distal coronary pressure multiplied by the hyperemic mean transit time (mm Hg • seconds, or units \[U\]). Myocardial Heterogeneity Index (Hi) was measured by an automated analysis developed in our research unit. Hi was finally calculated from images SPECT using a Markovian analysis. For this study Hi is given by the equation: Hi = Σm \[1/(1+m)2\]Pd(m).
Time frame: day 0 (inclusion)
scintigraphy
An FFR value of 0.80 or less identifies ischemia-causing coronary stenoses. The global summed stress score (SSS) was calculated by adding the scores of the 17 segments in the stress and rest images, respectively. Scans were considered as normal when SSS was \< 4.
Time frame: day 0 (inclusion)
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.