Myocardial Perfusion Scintigraphy Results Research Articles

Diyabetli Hastalarda Miyokard Perfüzyon Sintigrafisinde Miyokard İskemisini Öngörmede Ürik Asit-HDL Kolesterol Oranının Rolü

The Role of Uric Acid to HDL Cholesterol Ratio in Predicting Myocardial Ischemia in Myocardial Perfusion Scintigraphy in Diabetic Patients
 Abstract
 Objective: Diabetes Mellitus (DM) is a significant risk factor for cardiovascular diseases, particularly myocardial ischemia. Both diabetes mellitus type 2 and cardiovascular conditions are characterized by a high burden of inflammation. The uric Acid to High-Density Lipoprotein cholesterol ratio (UHR) has been suggested as a novel marker of metabolic and inflammatory diseases. Hence, this study investigated the predictive role of the Uric Acid to High-Density Lipoprotein cholesterol ratio (UHR) in myocardial ischemia detected by Myocardial Perfusion Scintigraphy (MPS) in diabetic patients.
 Materials and Methods: This study included patients who underwent MPS between January 2022 and March 2023 at the Nuclear Medicine Department of Abant Izzet Baysal University Hospital. Based on the MPS results, the participants were divided into normal perfusion and myocardial ischemia. Variables such as age, sex, leukocyte count, hemoglobin, hematocrit, platelet count, serum uric acid, urea, creatinine, total cholesterol, LDL-cholesterol, HDL-cholesterol, triglyceride, transaminase, blood fasting glucose, C-reactive protein, and serum albumin were recorded and compared between the groups.
 Results: Among the 73 diabetic patients, 37 had myocardial ischemia, and 36 had normal MPS. Serum uric acid levels were higher in the ischemic group (6.3 ± 1.5 mg/dL) than in the normal group (5.1 ± 1.8 mg/dL) (p

Comparison of Myocardial Perfusion Scintigraphy and Coronary Angiography Results in Breast Cancer Patients Treated with Radiotherapy.

Breast cancer is the most common type of malignancy in women and radiotherapy (RT) is an important part of treatment. Although it reduces cancer recurrence, it has been shown to cause accerelerated athnerosclerosis. This study aimed to compare the results of myocardial perfusion scintigraphy (MPS) for ischemia investigation with coronary angiography (CAG) findings and to investigate the effect of RT on the development of coronary artery disease in breast cancer patients who underwent RT. The results of 660 patients were analyzed and compared with each other in terms of clinical, demographic, laboratory parameters and MPS results. The mean age was 57.5 years and all of them were female. When the groups were compared, the Gensini score and marking of the left anterior descending artery (LAD) area as ischemic area localization were found more, but angiographically, the rate of severe stenosis in the area indicated by MPS was found to be lower in the RT group (p < 0.001). While the sensitivity of MPS in the RT group was 67.5% and non-RT group was 88.5% (p < 0.001), the result of our study shows that the sensitivity of the MPS test is significantly lower in the patient group receiving RT.

Evaluation of Myocardial Ischemia with Myocardial Perfusion Scintigraphy and 2D- Speckle Tracking Echocardiography in Non-Obstructive Coronary Artery Patient Group

Introduction: Strain analysis with 2D speckle tracking echocardiography could be used in the diagnosis of severe coronary artery disease. The aim of this study is to evaluate the effectiveness of 2D speckle tracking echocardiography in a group of patients with positive myocardial Perfusion Scintigraphy (MPS) but without severe coronary artery disease (CAD). Methods: Forty (25 female, age: 58.85±9.73) patients with the of angina pectoris and ischemia was found in MPS but non-obstructive CAD (&lt;50% stenosis) was observed in coronary angiography was included. Strain analysis was performed in all patients using 2D speckle tracking echocardiography. Longitudinal strains weremeasured for 17 LV myocardial segments. LV segments were grouped as ischemic and non-ischemic segments according to MPS results and strain parameters of 680 segments were compared. Results: The mean longitudinal strain values of the segments with ischemia were -20.24±6.0%, and the segments without ischemia were found as -20.11±6.46%, and no statistically significant difference was observed (p&gt;0.05). In subgroup analyzes based on gender, hypertension, diabetes mellitus, hyperlipidemia, and hypertriglyceridemia, no difference was observed between ischemic and non-ischemic segments in terms of longitudinal strain. Conclusion: In the patient group without severe coronary artery disease, no difference was observed between the staining parameters in the left ventricle 2D longitudinal strain analysis in terms of MPS positive segments and MPS negative segments. Considering previous studies, by using 2D strain analysis in combination with MPS, we can avoid unnecessary coronary artery angiography in special cases such as kidney failure, suspected MPS positivity.

The diagnostic value of SPECT CZT quantitative myocardial blood flow in high-risk patients

BackgroundThe objective of this study was to evaluate the accuracy of global MBF and MFR quantitation performed by myocardial perfusion scintigraphy (MPS) for the detection of multivessel coronary artery disease (CAD). Methods52 CAD patients underwent CZT MPS, with the evaluation of MBF and MFR, followed by invasive coronary angiography (ICA). According to MPS and ICA results, all patients were divided into three groups: (1) non-obstructive CAD and normal MPS scan (control group) (n = 7), (2) one vessel disease (1VD) (n = 16), (3) multivessel disease (MVD) (n = 29). ResultsGlobal absolute MBF and MFR were significantly reduced in MVD patients as compared to those with 1VD [0.93 (IQR 0.76; 1.39) vs 1.94 (1.37; 2.21) mL·min−1·g−1, P = .00012] and [1.4 (IQR 1.02; 1.85) vs 2.3 (1.8; 2.67), P = .0 004], respectively. The Syntax score correlated with global stress MBF (ρ = − 0.64; P < .0001) and MFR (ρ = − 0.53; P = .0003). ROC analysis showed higher sensitivity and specificity for stress MBF and MFR compared with semiquantitative MPS stress evaluation. Multivariate regression analysis showed that only stress MBF [OR (95% CI) 0.59 (0.42-0.82); P < .0003] was an independent predictor of MVD. ConclusionsQuantitative myocardial blood flow values assessed with the use of CZT camera may identify high-risk patients, such as those with multivessel disease.

Fatores Associados a Anormalidades na Cintilografia de Perfusão Miocárdica de Pacientes Diabéticos

Diabetes mellitus (DM) is the greatest risk factor for coronary artery disease. In addition to a long duration of diabetes, the presence of peripheral arterial disease and smoking are strong predictors of abnormalities on myocardial perfusion scintigraphy (MPS). This study aimed to assess the impact of risk factors in diabetic patients on MPS results and compare them with those of non-diabetic patients in a nuclear medicine clinic. A retrospective cross-sectional study was performed through the analysis of the medical records of patients who underwent MPS in 2010–2019. A total of 34,736 medical records were evaluated. Analyzing the stress phase of MPS, DM patients required two-fold more pharmacological stimulation than nondiabetic patients for MPS. Factors that negatively impact the MPS results were also evaluated, and DM (33.6%), insulin therapy (18.1%), systemic arterial hypertension (69.9%), dyslipidemia (53%), sedentary lifestyle (83.1%), use of pharmacological stress (50.6%), typical chest pain (8.5%), and limiting angina during the test (1.7%) were significantly associated (p &lt; 0.001) with test abnormalities

How to get the optimal defibrillation lead parameters using myocardial perfusion scintigraphy in patients with coronary artery disease.

The conventional criteria for a defibrillation lead (DL) implantation don't take into account presence of scar or deep ischemia in the myocardium. This may impair a proper functioning of the DL. We sought to optimize the DL implantation placement using rest myocardial perfusion scintigraphy (MPS), which allow detecting areas of myocardial hypoperfusion (MH). To study the influence of MH and scarring, detected by MPS, on the DL parameters in patients with coronary artery disease (CAD). 69 patients (male-65, age 64.8 ± 7.7years) with CAD and indications for ICD implantation were enrolled. Two days before ICD implantation all patients underwent MPS at rest. Then patients were divided in 2 groups. In the 1st group DL was implanted considering MPS results: to the septal position, if the most significant MH were detected in the apical segments, and to the apical position, if MH were in the septal segments. In the 2nd group DL was implanted using the conventional approach without considering MPS results. Clinical 12months follow-up was performed with ICD interrogation. Patients of both groups were comparable by clinical and scintigraphic parameters. In the same time, in the 1st group pacing threshold was lower (p < 0.0001) and ventricle signal amplitude was higher (p < 0.0001) comparing with the 2nd group at all control points. The presence of MH detected by MPS in the area of the DL placement worsens its parameters. The results of MPS in patients with CAD can be useful for optimization of DL placement.

The detection of multivessel coronary artery disease: the value of quantitative myocardial blood flow and coronary flow reserve assessment

Abstract Background/Introduction The recent Cadmium-Zinc-Telluride (CZT) camera for MPS allows evaluating absolute MBF and CFR, possibly increasing the accuracy in detecting of multivessel CAD. Purpose To evaluate the accuracy of myocardial blood flow (MBF) and coronary flow reserve (CFR) quantitation performed by myocardial perfusion scintigraphy (MPS) for the detection of multivessel coronary artery disease (CAD). Methods Fifty-two patients with suspected or known CAD were enrolled in the study. All patients underwent CZT MPS, with the evaluation of MBF and CFR, followed by invasive coronary angiography. According to MPS and coronary angiography results, patients were divided into three groups. 1) non-obstructive CAD and normal MPS scan (control group) (n=7), 2) one vessel disease (1VD) (n=16), with significant coronary stenosis (≥70%) in one major epicardial coronary artery, 3) multivessel disease (MVD) group (n=29), with two or more major epicardial coronary arteries with (≥70%) stenoses or with ≥50% LMA stenosis. Results Absolute MBF and CFR were significantly reduced in patients with MVD as compared to those with 1VD [0.93 (IQR 0.76; 1.39) vs 1.94 (1.37; 2.21) ml/min/g, p=0.00012] and [1.4 (IQR 1.02; 1.85) vs 2.3 (1.8; 2.67), p=0.0004], respectively. The Syntax score correlated with global stress MBF (ρ=−0.64; p&amp;lt;0.0001) and CFR (ρ=−0.53; p=0.0003). ROC analysis showed higher sensitivity and specificity for stress MBF (85.2% and 81%), and CFR (88.9% and 80%) compared with semiquantitative MPS stress evaluation (69% and 69%). Multivariate regression analysis showed that only stress MBF [OR (95% CI) 0.59 (0.42–0.82); p&amp;lt;0.0003] was an independent predictor of MVD. Conclusion The use of absolute myocardial blood flow analysis with the CZT camera may identify high risk patients, such as those with multivessel disease. This approach could be used in clinical practice, increasing the accuracy in the evaluation of patients with known or suspected coronary artery disease. Funding Acknowledgement Type of funding source: None

The levels of oxidative and nitrosative stress in patients who had 99mTc-MIBI myocardial perfusion scintigraphy and 99mTc-DMSA, 99mTc-MAG-3 renal scintigraphy.

Ionizing radiation is a strong stimulator of reactive oxygen specises (ROS) and reactive nitrogen species (RNS). These reactive species may cause oxidative and nitrosative stress. In this study, we aimed to evaluate possible effects of 99mTechnetium (99mTc)-methoxyisobuthylisonitrite (MIBI), 99mTc-dimercaptosuccinic acid (DMSA), 99mTc-mercaptoacetyltriglycine (MAG-3) on oxidative and nitrosative stress biomarkers in patients who were performed myocardial perfusion scintigraphy (MPS) and renal scintigraphy. Patients (n = 29) who were referred to nuclear medicine department were chosen as the patient group. They were divided into three subgroups according to the type of disease and 99mTc labelled agent. The first patient group had MPS (n = 9). The second patient group had 99mTc-DMSA renal scintigraphy (n = 12). The third patient group had 99mTc-MAG-3 renal scintigraphy (n = 8). The blood samples were taken from first, second and third patient groups 1 h, 3 h, 45 min after injection of the agent, respectively. The samples were taken from healthy volunteers (n = 25) as a control group. Alterations in catalase (CAT),superoxide dismutase (SOD), malondialdehyde (MDA) levels as oxidative stress biomarkers and nitric oxide (NO) and 3-Nitrotyrosine (3-NTx) levels as nitrosative stress biomarkers in all blood samples were evaluated. Results of MPS and renal scintigraphy performed patients were compared with control group separately. CAT, SOD, MDA and 3-NTx levels were higher in the first group than the control group (p < 0.05). Although NO levels were higher in the first group than the control group, it was not statistically significant (p > 0.05). CAT and SOD levels were lower in second and third groups than the control group (p < 0.0 5). However, MDA, NO, 3-NTx levels were higher in second and third groups than the control group (p < 0.05). These results show that oxidative and nitrosative balance is impaired due to ionization radiation. These reactive species might stimulate an adaptive and protective cellular defense mechanism in irradiated cells soon after exposure to radiation. Thereby, this mechanism protect organism from the effects of low dose ionizing radiation.

Increased symmetric dimethylarginine, but not asymmetric dimethylarginine, concentrations are associated with transient myocardial ischemia and predict outcome.

ObjectiveAsymmetric and symmetric dimethylarginines (ADMA and SDMA) are endothelial dysfunction markers. ADMA inhibits synthesis of nitric oxide. We aimed to analyze both markers in patients with coronary artery disease (CAD) who were referred for stress/rest myocardial perfusion scintigraphy (MPS).MethodsAll patients underwent a 2-day dipyridamole (DP) stress/rest protocol. Thereafter, patients with transient myocardial perfusion abnormality were followed up and their coronary blood flow was quantitatively assessed. Venous blood was taken before and after DP stress to measure markers.ResultsBaseline ADMA and SDMA concentrations were significantly higher in patients with CAD compared with healthy subjects. Pre- and post-stress SDMA concentrations were significantly higher in patients with transient myocardial perfusion abnormality compared with those with negative MPS results. However, ADMA and L-arginine concentrations were not significantly different between the two groups. None of the markers were significantly different between patients with angiographically proven low coronary flow and those with normal coronary flow. Pre-stress SDMA concentrations were an independent predictor of cardiovascular mortality during a 8-year follow-up.ConclusionsElevated serum SDMA concentrations may be helpful for selecting high-risk patients with CAD if there is any doubt in interpreting MPS. SDMA concentrations may also predict cardiovascular outcome.

Aortic Stiffness Index and Aortic Distensibility Measured by Echocardiography May Help to Improve the Equivocal Results of Myocardial Perfusion Scintigraphy

Aortic Stiffness Index and Aortic Distensibility Measured by Echocardiography May Help to Improve the Equivocal Results of Myocardial Perfusion Scintigraphy

Перфузионная сцинтиграфия миокарда и чрескожное коронарное вмешательство у пациентов со стенозирующим поражением коронарных артерий

Purpose of research. To study the relationship of varying degrees of stenotic lesions of the coronary arteries (CA) with the results of myocardial perfusion scintigraphy in railway workers before and after percutaneous coronary intervention (PCI). Material and methods. The study included 130 patients with SC stenosis more than 50% of the lumen (according to the results of invasive coronary angiography), all underwent single - photon emission computed tomography (SPECT) of the myocardium according to the two - day Protocol stress + rest”. When comparing the obtained data, the patients were divided into groups according to the degree of SC stenosis. Results. In 83 patients (group 1), SC stenosis was detected from 50 to 85%, in 47 patients (group 2) SC were stenosed by 85% or more. In ofect persistent defect of myocardial perfusion occurred in 32% of cases, reversible defect of perfusion (deterioration of perfusion in the sample with the load) - in 51%, deterioration of myocardial perfusion at rest (compared with the load) - in 17% of cases. In 56% of patients of the 1st group the deterioration of myocardial perfusion was revealed in the load test. In 60% of patients of group 2 myocardial perfusion disorders were persistent or worse than in the load test. Silent myocardial ischemia was diagnosed in 74% of patients of group 1 and 98% of patients of group 2. Every third patient with SMI conducted percutaneous coronary intervention (PCI), of whom half after PCI held SPECT of the myocardium. There were no cases of worsening myocardial perfusion in group 2 after PCI. In group 1, 6 cases out of 9 showed deterioration of myocardial perfusion or no effect of PCI. Conclusion. Stenotic lesions of KA less than 85% was associated with a higher incidence of deterioration of myocardial perfusion in the test with a load, whereas the CA stenosis more than 85% more likely to worsen the myocardial perfusion alone. All cases of worsening myocardial perfusion after PCI were observed in patients with SC stenosis less than 85%.

The diagnostic accuracy of myocardial perfusion scintigraphy in athletes with abnormal exercise test results.

Background Previous studies revealed a relatively high prevalence of electrocardiographic findings indicative for myocardial ischemia in asymptomatic athletes undergoing pre-participation screening. Myocardial perfusion scintigraphy is generally considered a valuable diagnostic and prognostic modality and often used for further diagnostic evaluation in these subjects. However, data on the diagnostic accuracy of myocardial perfusion scintigraphy in athletes are scarce. Objectives The main purpose of this study was to investigate the positive predictive value of myocardial perfusion scintigraphy for detection of coronary artery disease in asymptomatic athletes with abnormal exercise testing results during pre-participation screening. The secondary aim was to evaluate the prognostic value of myocardial perfusion scintigraphy. Methods Electronic charts of asymptomatic athletes who underwent myocardial perfusion scintigraphy following an abnormal exercise testing were retrospectively reviewed. Myocardial perfusion scintigraphy and exercise testing studies were revised. Athlete characteristics and cardiovascular risk factors were evaluated. Results One hundred and forty-three athletes were included. 29 athletes (20%) showed concordant abnormal exercise testing and myocardial perfusion scintigraphy results. Coronary imaging was performed in 20 of these 29 athletes. Four athletes showed significant coronary artery disease (positive predictive value = 20%). The positive predictive value increased to 33% when athletes were selected who should have undergone exercise testing according to the guideline recommendations. During a mean follow-up interval of 4.7 ± 2.2 years, eight cardiac events occurred. Athletes with an abnormal myocardial perfusion scintigraphy result had a fourfold increased risk at a future cardiac event (2.9%/year versus 0.75%/year, p = 0.031). Conclusions The positive predictive value of myocardial perfusion scintigraphy for the detection of significant coronary artery disease in asymptomatic athletes with a positive exercise testing result is low, even in a selection of athletes with a relatively high cardiovascular risk. Although an abnormal myocardial perfusion scintigraphy result was associated with a fourfold higher annual event rate, the absolute annual event rate in this group was still low. Efforts should be made to develop better diagnostic strategies to evaluate asymptomatic athletes with abnormal exercise testing results during pre-participation screening.

Prevalence of risk factors and asymptomatic carotid atherosclerosis in diabetic patients screened for silent myocardial ischemia by SPECT myocardial imaging.

The aim of the study was to evaluate whether there is any association between myocardial ischemia, common risk factors and carotid artery ultrasound parameters in asymptomatic type 2 diabetic (DMT2) patients. 60 asymptomatic DMT2 patients (pts) without known coronary artery disease (CAD) underwent one day rest Dypiridamole stress Tc-99m sestamibi single photon emission computed tomography myocardial perfusion scintigraphy (MPS). We used 17 segment models for perfusion analysis with the assessment of perfusion scores. Patients were studied for age, sex, hypertension, hyperlipidemia, hs-CRP, smoking, obesity and family history of cardiac disease. Color Ultrasound examination of carotid arteries was performed in all patients. 51 patients (pts) had hypertension, 48 pts had hyperlipidemia, 15 were smokers, 6 pts had BMI > 30 kg/m2 and 26 patients had positive family history for CAD. 18 (31%) patients had myocardial ischemia. Mild ischemia was found in 6 pts, moderate in 7 patients and severe ischemia in 5 patients. Carotid IMT was increased in 34 pts and 15 pts had carotid plaques. Mean c-IMT value in patients with normal MPS results was 0.7 ± 0.1; in moderate ischemia 0.9 ± 0.1 and in pts severe ischemia 1.0 ± 0.2. Multivariate analysis showed obesity, low HDL and increased diastolic blood pressure predictors of increased c-IMT. Increased pulse pressure (PP), age and non-HDL cholesterol were predictors for presence of carotid plaques. Multivariable analysis for prediction of stress induced ischemia showed OR 2.9 (95% CI 2.1-5.1) for male gender, OR 3.1 for systolic blood pressure (95% CI 1.9-3.8) and OR 2.8 for LDL cholesterol (95% CI 1.7-3.6). Our study has shown high prevalence of traditional risk factors and silent myocardial ischemia in type 2 diabetic patients, with the importance of SPECT imaging in selected diabetes type 2 patients. The study highlights the importance of screening for carotid atherosclerosis, which may be useful to identify diabetic patients at higher risk for coronary artery disease..

Assessment of Heart Rate Recovery with GATED-Myocardial Perfusion Scintigraphy Outcome in Patients with Coronary Artery Disease: A Retrospective Study and Institutional Experience.

Objective: This study aimed to investigate the effects of assessment with myocardial perfusion scintigraphy (MPS) and heart rate recovery (HRrec) measurements in combination to evaluate the current status of patients with a diagnosis or suspicion of coronary artery disease (CAD).Methods: A total of 350 patients were included in the study. CAD group consisted of 200 patients with stable angina pectoris and a known history of CAD, while the control group consisted of 150 patients with suspicious stress test who had no history of known CAD. In order to calculate the HRrec index, the treadmill exercise test was performed in all patients according to the Bruce protocol. The MPS results were evaluated for the presence or absence of myocardial ischemia and infarction by visual and quantitative (summed stress score and summed difference score) assessments.Results:When the MPS results and HRrec were evaluated together, there was no statistically significant difference in the non-CAD group. But, when GATED-MPS was evaluated alone in the triple-vessel patient group, 27 (36%) patients were found to be normal while evaluated with HRrec, four (5.3%) patients were found to be normal.Conclusion:HRrec measurements obtained during stress MPS is important in patient evaluation. Therefore, evaluation of MPS results and HRrec measurements together may provide a more accurate estimation of possible presence of CAD in patients.

Serum copeptin level can be a helpful biomarker in evaluation of myocardial perfusion scintigraphy results

Myocardial perfusion scintigraphy (MPS) is a well-established diagnostic tool. The sensitivity and specificity of single photon emission computed tomography (SPECT) MPS to detect significant coronary lesion were 86% and 74%, respectively. The aim of this study was to examine the role of serum copeptin in evaluation of MPS. Sixty-two consecutive patients underwent both SPECT MPS using 99mTc-sestamibi and transthoracic echocardiography were enrolled prospectively. Age, gender, height, weight, presence of cardiovascular risk factors were recorded. Exercise treadmill test (ETT) with modified Bruce protocol was used to induce coronary ischemia during MPS. While performing MPS, blood samples for serum copeptin level were drawn three times at pre-exercise, at the peak of ETT, and 6 h after ETT, respectively. The patients were enrolled into three groups according to MPS results (normal, equivocal and ischemia). The study included 62 patients (23 with normal, 20 with equivocal, 19 with ischemia on MPS). Pre-, peak-, and post-exercise B-type natriuretic peptide and troponin I values were similar across the groups (p > 0.05 for all comparisons). Serum copeptin values for pre- and peak-exercise were similar among all groups (p = 0.883 and p = 0.089). Post-exercise copeptin values of the normal and equivocal groups were similar (p = 0.661, z = -0.438) while that of the ischemia group was significantly higher than both the normal (p < 0.001) and equivocal group (p < 0.001). Serum copeptin was found to be increasing significantly in case of ischemia on MPS. It may be used in differentiation of equivocal results from false positive results.

Can Ischemia Modified Albumin Help In Differentiating Myocardial Perfusion Scintigraphy Results?

Myocardial perfusion scintigraphy (MPS) is a diagnostic tool commonly used to detect significant coronary lesion. However equivocal, false negative or positive results can be yielded. Controversial findings regarding the role of ischemia-modified albumin (IMA) in MPS evaluation persist. The aim of the present study was to examine the role of serum IMA in the assessment of MPS results. MPS using technetium (99mTc) sestamibi and transthoracic echocardiography was performed on 62 consecutive subjects prospectively enrolled. Exercise treadmill test (ETT) with modified Bruce protocol was used to induce coronary ischemia. During MPS performance, blood samples for serum IMA were obtained at 3 times: at pre-exercise, at the peak of ETT, and 6 hours after ETT. Patients were classified into 3 groups according to MPS results (normal, equivocal, and ischemia). Sixty-two patients (23 normal, 20 equivocal, 19 with ischemia) were included. Pre- and peak-exercise IMA values were similar among the groups (p=0.706 and 0.904). Post-exercise IMA values of the normal and equivocal groups were similar (p=0.733), while that of the ischemia group was significantly higher than the values of either the normal (p<0.001) or equivocal groups (p<0.001). ΔIMA (the difference between post-exercise and peak-exercise IMA) of the ischemia group was significantly higher than that of either the normal (p<0.001) or equivocal groups (p<0.001). Serum IMA was found to be significantly increased in cases of ischemia on MPS. Subjects with normal and equivocal MPS had a similar pattern during the test. IMA may be used in differentiation of equivocal results from false positive results.

The use of pre-test and post-test probability values as criteria before selecting patients to undergo coronary angiography in patients who have ischemic findings on myocardial perfusion scintigraphy.

Objective:Myocardial perfusion scintigraphy (MPS) is a diagnostic test which is frequently used in the diagnosis of coronary heart disease (CHD). MPS is generally interpreted as ischemia present or absent; however, it has a power in predicting the disease, similar to other diagnostic tests. In this study, we aimed to assist in directing the high-risk patients to undergo coronary angiography (CA) primarily by evaluating patients without prior CHD history with pre-test and post-test probabilities.Methods:The study was designed as a retrospective study. Between January 2008 and July 2011, 139 patients with positive MPS results and followed by CA recently (<6 months) were evaluated from patient files. Patients’ pre-test probabilities based on the Diamond and Forrester method and the likelihood ratios that were obtained from the literature were used to calculate the patients’ post-exercise and post-MPS probabilities. Patients were evaluated in risk groups as low, intermediate, and high, and an ROC curve analysis was performed for the post-MPS probabilities.Results:Coronary artery stenosis (CAS) was determined in 59 patients (42.4%). A significant difference was determined between the risk groups according to CAS, both for the pre-test and post-test probabilities (p<0.001, p=0.024). The ROC analysis provided a cut-off value of 80.4% for post-MPS probability in predicting CAS with 67.9% sensitivity and 77.8% specificity.Conclusion:When the post-MPS probability is ≥80% in patients who have reversible perfusion defects on MPS, we suggest interpreting the MPS as “high probability positive” to improve the selection of true-positive patients to undergo CA, and these patients should be primarily recommended CA.

Comparison of fragmented QRS and myocardial perfusion-gated SPECT findings

Fragmented QRS (fQRS) complex is an ECG parameter that has recently been introduced and investigated. It is assumed that fQRS occurs because of disruptions in ventricular conduction due to ventricular infarction and ischemia. Therefore, in this article, we aimed to investigate the relationship between the detection of infarction and ischemia on myocardial perfusion-gated single-photon emission computed tomography images and appearance of fQRS on ECG. We retrospectively reviewed the records of patients with a diagnosis of coronary artery disease who were referred to our institution for myocardial perfusion scintigraphy. In total, 261 patients (122 women and 139 men, with a mean age of 61±10.33 years) with and without fQRS (136 and 125, respectively) were included in the present study. The myocardial perfusion scintigraphy results were evaluated for the presence or absence of myocardial ischemia and infarction by visual and quantitative (summed stress score, summed rest, summed difference score, summed motion score, and summed thickening score) assessments. Statistical analysis was performed to determine the relationship between the presence of fQRS and myocardial ischemia and/or infarction. Student's t-test and the Mann-Whitney U-test were used for comparing the results. Pearson's χ2-test and Fisher's exact tests were also used to compare the distribution of variables between the two groups. The prevalence of ischemia and infarction were found to be, respectively, 4.38-fold and 5.95-fold higher in patients with fQRS compared with the control group. Moreover, the prevalence of both ischemia and infarction was found to be 10.54-fold higher in patients with fQRS compared with the control group. There is a highly statistically significant possibility of detecting ischemia and infarction in perfusion myocardial scintigrams of patients whose ECGs have fQRS.

Prognostic value of myocardial perfusion scintigraphy for patients suspected of and diagnosed with coronary artery disease

The prognostic value of myocardial perfusion scintigraphy (MPS) continues to attract interest and provoke discussions.This study was an attempt to investigate the methods. Determination of the prognostic value of MPS for patients suspected of and diagnosed with coronary artery disease (CAD). The study group included 215 patients, 134 males and 81 females, aged 21-66, mean age 48. Tc-99m-MIBI myocardial perfusion scintigraphy was performed and information concerning the diagnosis, aim of the examination, past coronary episodes, clinical condition, duration and type of complaints, concomitant diseases, test results, revascularisation procedures and pharmacological treatment was gathered. Further history of the patients was monitored throughout the observation period of 52 months on average. The patients were divided into the following two groups: Group I - suspected coronary artery disease: 124 patients aged 21-65,59 males and 65 females; Group II - diagnosed coronary artery disease: 91 patients aged 31-66, 75 males and 16 females diagnosed with CAD, including 39 s/p myocardial infarct, 31s/p infarct and revascularisation, 21 s/p revascularisation. The probability of CAD was calculated using the Diamond method for the patients suspected of CAD. The obtained results were examined in a statistical analysis. Normal MPS results were obtained for 94/124 patients suspected of CAD, 15/91 patients diagnosed with CAD,64/81 females and 45/134 males. In Group I, apart from pathological MPS results, reversible ischemia was determined in as many as 27/30 patients, and only 17/91 patients in Group II. No patients with normal MPS results suffered major cardiac events,only one of them underwent revascularisation. Major cardiac events occurred in the case of patients with pathological MPS results: Group I - 2 myocardial infarcts and 2 cardiac deaths,Group II - 3 infarcts and 10 cardiac deaths. Minor cardiac events, apart from one case, were also only observed in the case of patients with pathological MPS results: Group I - 10 revascularisations and one case of unstable CAD, Group II- 12 revascularisations and 7 cases of unstable CAD. Patients with normal MPS results and stenosis in coronary angioraphy suffered no cardiac events. Cardiac events occur mostly in the group with a medium and high risk of CAD and in the case of patients diagnosed with CAD. 1. Normal MPS results for patients suspected of or diagnosed with CAD: s/p infarct and/or CABG prognosticate a mild course of the disease, without or with a minimal number of cardiac events, also in a longer observation period.2. Pathological MPS results clearly imply a greater risk of cardiac events, and the number of events increases with the greater probability of CAD and with the patient's age. 3. Normal MPS results, even with significant stenosis in coronary angiography,prognosticate a low risk of cardiac events.

The Limited Usefulness of the Treadmill Test or a Risk-guided Approach in Screening for Asymptomatic Coronary Heart Disease in Japanese Patients with Type 2 Diabetes

We prospectively investigated the efficacy of the screening methods for asymptomatic coronary heart disease (CHD) in Japanese patients with type 2 diabetes using the treadmill tolerance test (TTT) as a first-line test or the American Diabetes Association (ADA) guidelines. The subjects included consecutive inpatients with type 2 diabetes (n=331) assessed with both electrocardiogram (ECG) at rest and TTT. Subjects with abnormal TTT findings were evaluated using stress myocardial perfusion scintigraphy (MPS). A total of 60 out of 69 subjects with positive TTT findings underwent MPS, among whom a total of 22 subjects (6.6% of the total number of subjects) had positive MPS results. Among those with positive MPS results, a total of 14 subjects underwent coronary angiography, eight of whom were determined to have significant coronary artery stenosis. The prevalence rates of hypertension and micro/macroalbuminuria were significantly higher in the MPS-positive group (77.3% and 54.5%, respectively) than in the TTT-negative group (44.7% and 27.1%, respectively). Among the subjects with positive MPS results, 68.2% met the 1998 ADA criteria. Neither the TTT as a first-line test nor the ADA guidelines are sufficiently adequate screening methods to detect asymptomatic CHD in Japanese subjects with type 2 diabetes. Conducting routine screening for asymptomatic CHD in Japanese patients with type 2 diabetes may therefore not be very useful.