Use of neutrophil/lymphocyte ratio as a marker in patients with suspicious diaphragmatic attenuation artifact

Objective: This study aimed to evaluate whether neutrophil/lymphocyte (N/L) ratio assists in the diagnosis of coronary artery disease (CAD) in patients with suspected diaphragmatic attenuation artifact (DAA) on myocardial perfusion SPECT (MP-SPECT). Material and Methods: A total of 255 patients undergoing coronary angiography between 2015-2020 due to unclear DAA of the inferior wall on MP-SPECT were included in this retrospective study. Patients were divided into two groups (CAD and non-CAD) according to angiographic images. Significant CAD was defined as ≥50% stenosis of coronary arteries feeding the inferior wall. White blood cell count, biochemical parameters, and risk factors for CAD were compared between the two groups. Results: There was no statistically significant difference between the two groups in terms of age (p = 0.055), gender (p = 0.482), and body mass index (p = 0.305). N/L ratio (OR = 1.397 p = 0.002 95% Cl = 1.128-1.732) and left ventricle ejection fraction (OR = 0.896 p = 0.023 95% Cl = 0.815-0.985) were independent risk factors for CAD in multivariate binary logistic regression analysis. Receiver Operating Characteristic (ROC) curve analysis showed that a cut-off value of ≥2 for N/L ratio predicted the presence of CAD (sensitivity=63.5%, specificity=60.7%, AUC=0.668, 95% CI=0.596 – 0.740, p<0.001). Conclusion: N/L ratio is a simple and accessible test and may increase the diagnostic accuracy of MP-SPECT for CAD in patients with suspicious diaphragmatic attenuation on MP-SPECT.

Challenges of gated myocardial perfusion SPECT processing

The paper provides an in-depth look at gated myocardial perfusion single photon emission computed tomography (SPECT) data processing. Attention paid to several unmentioned subjects of the quantitative analysis of gated myocardial perfusion SPECT data. The article considers several options in the construction process of the ellipsoid coordinate system of the left ventricle (LV). Mathematical representation of polar maps is given. Formulas of the regional parameters calculation are proposed. Issues of phase analysis are explored.

The COronary and MICrocirculatory measurements in patients with Aortic valve Stenosis (COMIC-AS) study: Rationale and design

Objective: Although coronary artery disease (CAD) is frequent in patients with aortic stenosis (AS), hemodynamic assessment of CAD severity in patients undergoing valve replacement for severe AS is challenging. Myocardial hypertrophic remodelling interferes with coronary blood flow and may influence the values of fractional flow reserve (FFR) and non-hyperemic pressure ratios (NHPRs). The aim is to investigate these effects on current CAD indices by comparing intra-coronary hemodynamics prior to, immediately after and six months after aortic valve replacement (AVR), when it is expected that microvascular function has improved. Furthermore, we will compare FFR and Resting Full Cycle Ratio (RFR) with myocardial perfusion SPECT as indicators of myocardial ischemia in patients with AS and CAD. Study design: One hundred patients with AS and CAD will be prospectively included. Patients will undergo pre-AVR SPECT and intra-coronary hemodynamic assessment at baseline, immediately after and six months after AVR. The primary endpoint is the change in FFR. Secondary endpoints include the acute change of FFR after TAVR, the diagnostic accuracy of FFR versus RFR compared with SPECT for the assessment of ischemia, changes in microvascular function as assessed by the index of microcirculatory resistance (IMR), and the effect of these changes on FFR.Conclusion: The present study will evaluate intra-coronary physiology before, immediately after and six months after AVR in patients with AS and intermediate coronary stenosis. The understanding of the impact of AVR on the assessment of FFR, NHPR and microvascular function may help guide the need for revascularization in these patients.

The Role of Myocardial Perfusion Imaging in Patients with Diabetes Mellitus

Diabetes mellitus is a complex pathology with increasing incidence, associated with an increased risk of coronary heart disease. Myocardial perfusion imaging (MPI) is an important diagnostic tool for the evaluation of coronary artery disease (CAD), with a high prognostic value. Objective. The aim of this study was to evaluate the role of stress-rest MPI in the assessment of patients with DM and suspected or confirmed CAD. Method. We performed a retrospective analysis of 128 patients who underwent stress-rest MPI in our department, all of them with coronary angiography (CA) available. All patients underwent stress rest myocardial perfusion SPECT using a 1-day or 2-day protocol. The radiopharmaceuticals used were 99m-Tc-MIBI or tetrofosmin. The study was performed with a gated protocol SPECT, synchronous with the ECG, using a dual-head gamma camera. Patients were divided in 4 subgroups based on the presence of DM and of significant CA changes. Results. In the group of patients with significant coronary disease on CA and previously diagnosed DM, number of perfusion defects on the stress-rest MPI were higher and also the presence of systolic disfunction and the severity of defects. Our results support the idea that the severity and extent of myocardial perfusion defects are greater in diabetic patients than in non-diabetic patients. Conclusions. We can consider myocardial perfusion SPECT with 99mTc-labeled agents as a feasible method for the diagnosis and evaluation of CAD and for the management of diabetic patients.