Cut-off values of myocardial blood flow using cardiac-dedicated CZT SPECT

While not the primary mechanism or hallmark for the pathogenesis of all myocardial disease, coronary microvascular disease is acknowledged to play a crucial role in the diagnostic and prognosis of different diseases. PET is considered the non-invasive gold standard for evaluating myocardial blood flow, but SPECT-CZT cameras have become a promising and comparable tool for this purpose, more widespread in some countries. However, each SPECT-CZT trademark possesses different characteristics and each service adopts different protocols. This requires establishing specific cut-off values for our recently installed CZT SPECT camera.

The aim of this study is to determine cut-off values of myocardial blood flow (MBF) using a cardiac-dedicated CZT SPECT in our population.

We prospectively analyzed 109 patients who underwent gated-SPECT using a cardiac-dedicated CZT SPECT. Of these, 43 (39.4%) subjects correspond to a control group (with normal myocardial perfusion in rest and stress, normal gated, normal coronary CT, without myocardial hypertrophy, diabetes or valvular heart disease, all subjects asymptomatic and in sinus rhythm) and 66 (60.6%) patients correspond to a pathological group (angina:10, diabetes: 23, dyspnea: 7, heart failure: 3, non-fatal myocardial infarction: 14, left ventricular ejection fraction <50%: 9, coronary artery disease: 14, coronary revascularization: 9, valvular heart disease: 8). The cut-off values for MBF at rest (MBF-rest), MBF during stress or hyperemic phase (MBF-stress), MBF reserve (MBF-reserve: defined as MBF-stress/MBF-rest), and MBF differences (MBF-differences: MBF-stress - MBF-rest) were investigated. Statistical analyses were performed with Receiver Operating Characteristics (ROC) curve analysis using STATA 18. StataCorp, College Station, TX, USA.

In order to differentiate control group and pathological group, cut-off values were (Results Table):

Different cut-off values of MBF were observed between subjects and patients using a cardiac-dedicated CZT SPECT camera.

Results Table