Summed Difference Score Research Articles

The effect of cardiac shock wave therapy on myocardial function and perfusion in the randomized, triple-blind, sham-procedure controlled study

BackgroundRecent triple-blind sham procedure-controlled study revealed neutral effects of the cardiac shock wave therapy (CSWT) on exercise tolerance and symptoms in patients with stable angina. Current data about the effects of CSWT on global and regional myocardial contractility and perfusion is limited. Hereby we report the results of an imaging sub-study that evaluated the capacity of CSWT to ameliorate myocardial ischemia induced during dobutamine stress echocardiography (DSE) and cardiac single photon emission computed tomography (SPECT).MethodsProspective, randomized, triple-blind, sham procedure-controlled study enrolled 72 adult subjects who complied with defined inclusion criteria. The subjects were assigned to the OMT + CSWT and the OMT + sham procedure study groups with 1:1 ratio. Application of the CSWT covered all segments of the left ventricle. Imaging ischemia tests were performed in 59 study patients: DSE and SPECT before the CSWT treatment and after 6 months, with DSE carried out additionally at 3 months after randomization. Co-primary endpoints of the study were: change in wall motion score index (WMSI), representing the stress-induced impairment of regional myocardial function, and change in summed difference score (SDS), representing the amount of perfusion defect.ResultsOMT + CSWT and OMT + sham procedure study groups included 30 and 29 patients, respectively. Regional myocardial contractility during DSE significantly improved at 3 months follow-up in OMT + CSWT group compared to baseline as shown by WMSI at stress (1.4 ± 0.4 vs 1.6 ± 0.4, p = 0.001), but not in OMT + sham procedure group (1.5 ± 0.3 vs 1.6 ± 0.4, p = 0.136). The difference in stress DSE results between both study groups disappeared after 6 months. SPECT results demonstrated a significant reduction of inducible ischemia in OMT + CSWT group compared to OMT + sham procedure group at 6 months follow-up (SDS dropped from 5.4 ± 3.7 to 3.6 ± 3.8 vs 6.4 ± 5.9 to 6.2 ± 5 respectively, p = 0.034).ConclusionsCardiac shock wave treatment showed the ability to reduce stress-induced myocardial ischemia, as assessed by wall motion abnormalities and perfusion defects, compared to sham procedure.Trial registrationClinicaltrials.gov (NCT02339454). The trial was registered retrospectively on 12 January 2015.

Evaluation of Myocardial Perfusion Imaging SPECT Parameters and Pharmacologic Stress Test with Adenosine Versus Coronary Angiography Findings: Are They Diagnostically Concordant?

Objectives:In this study our first aim was to evaluate the diagnostic concordance of myocardial perfusion scintigraphy (MPS) by pharmacological stress test with adenosine (APST) with coronary angiography (CAG). The secondary aim of this study was to evaluate the correlation between CAG findings and automated analysis parameters such as left ventricular ejection fraction, summed stress score (SSS), summed rest score, summed difference score (SDS), stress MPS defect percentage ratio (extent) and transient ischemic dilation (TID) obtained by myocardial perfusion imaging single-photon emission computed tomography (SPECT).Methods:A total of 129 patients (62 male, 67 female, median age: 60.02) undergoing MPS due to suspicion of coronary ischemia who also underwent subsequent CAG in the last year were included in this study, their MPS data and CAG results were compared.Results:There was no statistically significant diagnostic concordance when visual evaluation of MPS, quantitative MPS parameters and exercise treadmill test (ETT) electrocardiography results were used alone. In fact, diagnostic concordance was higher when automated analysis parameters like TID, SSS and extent values were added to MPS SPECT visual analyses. There was diagnostic concordance in 57.9% of APST patients and 41.7% of ETT patients. There was diagnostic concordance in 75.8% of APST patients and 52.6% of ETT patients who were older than 65 years of age.Conclusion:In our study, we found that the use of APST during MPS increases diagnostic concordance with CAG. Therefore, we think that it would be appropriate to use APST in women and elderly patients with limited exercise habits. The CAG diagnostic mismatch is far above what it should be when MPS reporting is only done with visual data, and it is not supported by quantitative data such as TID, SSS, SDS and extent.

Complete revascularization determined by myocardial perfusion imaging could improve the outcomes of patients with stable coronary artery disease, compared with incomplete revascularization and no revascularization

ObjectivesTo compare the outcomes among patients treated by complete coronary revascularization (CCR) or incomplete coronary revascularization (ICR) and no coronary revascularization (NCR) by myocardial perfusion imaging (MPI), as well as to evaluate the impact of severity of ischemia on patients with coronary artery disease (CAD) by different therapy strategies. BackgroundUsing myocardial ischemia severity determined by MPI guiding treatment strategies for CAD patients still lacks strong clinical evidences. MethodsConsecutive patients (N = 286) underwent clinical stress-rest SPECT MPI and were retrospectively followed-up. For assessment of outcome of treatment, all patients were classified into three groups (CCR, ICR, and NCR), and further divided into two subgroups as mild ischemia (< 10% ischemic myocardium) and moderate-severe ischemia (≥ 10% ischemic myocardium). All-cause death was defined as the primary endpoint, and the composite of deaths, nonfatal myocardial infarction, and repeat revascularization (MACE) as the secondary endpoint. ResultsTwo-hundred eighty-six patients were followed-up for 46 ± 21 months. Thirty deaths and 65 MACEs were recorded. Patients treated by revascularization had significantly lower MACE (P < .001) but not mortality (P = .158) than patients treated by NCR. Outcomes of CCR related to mortality rate were greater than ICR and NCR (death: P = .019, MACE: P < .001). In patients with moderate-severe ischemia, CCR showed improved outcomes than ICR and NCR (death: P = .034; and MACE: P < .001). In patients with mild ischemia, the outcomes of CCR, ICR, and NCR had no significant difference (P > .05). Multivariate regression Cox analysis revealed that summed difference score [death: HR 1.09 (1.03, 1.15), P = .004] was an independent risk factor and CCR was an independent negative predictor [death: HR 0.31 (0.12, 0.81), P = .017; MACE: HR 0.30 (0.16, 0.57), P < .001]. ConclusionsOutcomes of patients treated by CCR were most likely more promising in comparison with treatment of ICR and NCR, especially when patients had over 10% ischemic myocardium.

Additional value of systolic wall thickening in myocardial stunning evaluated by stress-rest gated perfusion SPECT

Aim and patientsThe aim of the present study is to evaluate the additional value of systolic wall thickening to myocardial perfusion in diagnosing myocardial stunning in patients with angiography proven coronary artery disease. We selected 91 ischemic patients (82 males; mean age 59.7 ± 10.3) with CAD documented by angiography. Ischemia was defined as a summed difference score ≥5. All patients underwent a 2-day gated perfusion SPECT protocol. The patients received a dose of 740 MBq of 99mTc-tetrofosmin after stress and at rest. Treadmill maximal exercise tests were performed on all patients. ResultsThe post-stress LVEF was significantly lower than rest LVEF (48.1% ± 10.3% vs 50.3% ± 10.7%; P = .0001). The wall thickening summed difference score was 4.44 ± 4.13 (P = .0001). At a multivariate regression analysis, only WT-SDS as independent variable was significantly correlated with myocardial ischemia (SDS). We also divided patients according to SDS in those with mild (SDS < 8) and severe (SDS ≥ 8) ischemia. WT-SDS, but not ∆LVEF, was significantly different between groups. ConclusionsWT-SDS, more than the depression in the global function (∆LVEF) of the left ventricle, correlates with the degree of ischemia and better identifies, when present, the stunning phenomenon.

A novel clinical risk prediction model for myocardial infarction, coronary revascularization, and cardiac death according to clinical, exercise, and gated SPECT variables (VH-RS).

To create a risk score for cardiac events (CE) according to clinical, exercise, and gated SPECT variables. We analysed 5707 consecutive patients; 3181 patients (age 64.2 ± 11 years, male 59.6%) with suspected coronary artery disease (CAD) [without previous myocardial infarction (MI) or coronary revascularization (CR)] and 2526 patients (age 63.3 ± 11 years, male 81.7%) with established CAD (with previous MI or CR). To create the Vall d'Hebron Risk Score (VH-RS), first we analyse the predictors of CE (non-fatal MI, CR, and/or cardiac death), then the probability of CE for every patient according to the predictive variables. According to risk we stratified patients into four risk levels: very low risk (VLR), low risk (LR), moderate risk (MR), and high risk (HRi) using Multiple Cox Regression analysis models. Finally, we validate the VH-RS in another prospective cohort of 734 patients. In patients with suspected CAD; age (P < 0.001); gender (P = 0.001); hyperlipidaemia (P < 0.001); nitrates (P = 0.04); ejection fraction (EF) (P = 0.001); summed stress score (P < 0.001); METs (P < 0.001); exercise angina (P = 0.006); and mm of ST segment depression (P = 0.004) were the independent predictors of CE (C-statistic: 0.8; P < 0.001). In patients with established CAD, EF (P < 0.001); summed difference score (P = 0.001); age (P < 0.001); smoker (P = 0.002); nitrates (P = 0.003); exercise angina (P = 0.001); METs (P < 0.001); and mm of ST segment depression (P = 0.011) were the independent predictors of CE (C-statistic: 0.7; P < 0.001). The risk score obtained from these variables allows the stratification of patients into four risk levels: VLR, LR, MR, and HRi. The cardiac risk stratification by mean of clinical, exercise, and gated SPECT variables is an objective aid to assessing an individual's cardiac risk.

The Relation of Psychosocial Distress With Myocardial Perfusion and Stress-Induced Myocardial Ischemia.

Mental stress-induced myocardial ischemia is a frequent phenomenon in patients with coronary artery disease (CAD). The link between an integrated measure of chronic psychosocial distress and mental stress-induced myocardial ischemia, and whether it differs by sex, has not been examined before. We used latent class analysis to derive a composite measure of psychosocial distress integrating scales of depression, posttraumatic stress, anxiety, anger, hostility, and perceived stress in 665 individuals with stable CAD. Participants underwent myocardial perfusion imaging with mental stress and perfusion defects were quantified at rest (summed rest score), with mental stress (summed stress score), and their difference (summed difference score), the latter being an index of inducible ischemia. The M (SD) age was 63 (9) years, and 185 (28%) were women. Latent class analysis characterized the study sample into four distinct classes of incremental psychosocial distress. In women, class 4 (highest distress) had an adjusted 4.0-point higher summed rest score (95% confidence interval = 0.2-7.7) as compared with class 1 (lowest distress), whereas no difference was observed in men (-0.87 points, 95% confidence interval = -3.74 to 1.99, p = .04 for interaction). There was no association between the psychosocial distress latent variable and summed difference score in either women or men. Among patients with CAD, a higher level of psychosocial distress is not associated with mental stress ischemia, but it is associated with more resting (fixed) perfusion abnormalities in women only, as well as with blunted hemodynamic response to mental stress in both men and women.

Differential Impact of Appropriate Use Criteria on the Association between Age and an Abnormal Stress Myocardial Perfusion SPECT.

The diagnostic and prognostic value of appropriate use criteria (AUC) for coronary artery disease (CAD) is well established. Whether the diagnostic yield of AUC for predicting CAD is preserved among the elderly is not known. We analyzed a multi-site prospective cohort of 1511 consecutive patients (mean age 59 ±13 years, 57% males) who underwent outpatient, community-based SPECT myocardial perfusion imaging (MPI). Appropriateness of the studies was determined based on the 2013 multimodality AUC for detection and risk assessment of stable ischemic heart disease. An abnormal SPECT MPI was defined by either a summed stress score ≥ 4 or a summed difference score ≥ 2. Abnormal SPECT MPI was present in 190 patients (12.5%), while ischemia on MPI alone was present in 122 (8%). In multivariate logistic regression analysis, age ≥ 60 years, male gender, hypertension, diabetes mellitus, and known CAD were independent predictors of an abnormal SPET MPI, while appropriate indication of testing was not. Age ≥ 60 years was also an independent predictor of inducible myocardial ischemia, while appropriate indication for testing was not. Among elderly (≥ 60 year), regardless of appropriateness of testing, there was no difference in the prevalence of an abnormal SPECT (19% vs. 14%, p=0.14) or prevalence of SPECT ischemia (11% vs. 11%, p=1.00). Among younger patients however, appropriate testing predicted a greater prevalence of an abnormal SPECT (12% vs. 7%, p=0.013). In this multi-site cohort, testing based on AUC did not discriminate the risk of an abnormal SPECT MPI among the elderly. Caution is advised when relying on AUC for referring elderly patients for SPECT MPI.

Myocardial Ischemia Correlates with Left Ventricular Systolic Dysfunction in Patients with Noncompaction Cardiomyopathy

Purpose Noncompaction cardiomyopathy (NCC) results as an arrest of the myocardial compaction process in the embryonic period, leading to the impaired formation of the microvasculature. Myocardial perfusion abnormalities have already been described, however, the functional impact in NCC patients remains undefined. We sought to analyze a potential correlation between myocardial ischemia and heart failure progression in patients with NCC. Methods We enrolled 37 (24 male, 13 female) patients with NCC, average age 47±15 years. Echocardiography determined left ventricular end diastolic diameter and volume (EDD and EDV) and ejection fraction (LVEF). Global longitudinal strain (GLS) postprocessing has been performed. Serum levels of NT-proBNP have been measured. Cardiac MRI has been performed to confirm the diagnosis. Myocardial SPECT was performed at rest and on stress, determining summed difference score (SDS). Significant myocardial ischemia was defined as SDS≥2. Results Myocardial ischemia has been shown in 15 patients (41%, Group A), 22 patients (59%) showed no significant ischemic changes (Group B). The two groups did not differ in sex (male 73% vs. 59% in Group B), age (48±15 years vs. 46±14 years, P=0.65), creatinine (76±14 μmol/L vs. 76±16 μmol/L, P=0.98) or bilirubin (11±6 μmol/L vs. 12±5 μmol/L, P=0.46). When compared to Group B, Group A had significantly lower LVEF (38±15% vs. 55±13% in Group B, P=0.001), higher EDD (6.3±0.9 cm vs. 5.2±0.7 cm, P Conclusion In patients with NCC myocardial ischemia correlates with lower ejection fraction and dilation of the left ventricle, leading to greater neurohumoral activation. As medical heart failure therapy has not been shown to be successful in NCC patients, progressive LV systolic dysfunction due to myocardial ischemia often warrants heart transplantation or left ventricular assist device implantation. Treatment approaches targeting myocardial ischemia, such as CD34+ cell therapy, could slow the progression of disease in NCC patients.

Most Important Prognostic Values to Predict Major Adverse Cardiovascular, Cerebrovascular, and Renal Events in Patients with Chronic Kidney Disease Including Hemodialysis for 2 Years

Patients with chronic kidney disease (CKD) have an increased risk of adverse cardiovascular/cerebrovascular events. The aim of this study is to clarify whether stress myocardial perfusion single-photon emission computed tomography (SPECT) could predict cardiovascular/cerebrovascular events. In the Gunma-CKD SPECT Study, a multicenter prospective cohort trial, 311 patients with CKD (estimated glomerular filtration rate < 60 min/mL/1.73 m²) including 50 patients on hemodialysis underwent stress ^99mTc-tetrofosmin SPECT for suspected ischemic heart disease and were followed for 2 years. The primary endpoint was the occurrence of cardiac death (CD), while the secondary endpoint was major adverse cardiovascular/cerebrovascular and renal events (MACCRE). MACCRE occurred in 91 out of 286 patients (CD in 13 and other MACCRE in 78 patients). According to a multivariate Cox analysis, hemoglobin (Hb) and end-systolic volume (ESV) were associated with CD (p < 0.05), while the summed difference score, diabetes mellitus (DM), and Hb were associated with MACCRE (p < 0.05). Kaplan-Meier analysis showed that the CD-free rate was higher in patients with ESV < 105 mL (log-rank, p = 0.0013), Hb > 12 g (log-rank, p = 0.0036), and a summed stress score < 6 (log-rank, p = 0.0058). The MACCRE-free rate was higher in patients with SDS = 0 (log-rank, p = 0.0097), without DM (log-rank, p = 0.0091), and with Hb > 12 g (log-rank, p = 0.0023). Myocardial perfusion SPECT parameters as well as renal anemia and DM can be reliable prognostic markers in patients with CKD including hemodialysis.

Diagnostic value of peak filling rate derived from ECG-gated myocardial perfusion SPECT for detecting myocardial ischaemia in patients with non-obstructive coronary artery disease

Background: Left ventricular (LV) diastolic dysfunction represents an earlier step of the ischaemic cascade. We tested the hypothesis that the index of LV diastolic function from electrocardiogram (ECG)-gated single photon emission computed tomography (SPECT) is useful in detecting myocardial ischaemia in patients with non-obstructive coronary artery disease (CAD).Methods: One-hundred-ten patients with non-obstructive CAD and summed redistribution score of zero were enrolled. Summed difference score (SDS) of ≥2 was considered as the presence of myocardial ischaemia. Peak filling rate (PFR) defined as the maximum dV/dt divided by LV end-diastolic volume was obtained as the index of LV diastolic function.Results: Of 110 patients with non-obstructive CAD, 51 patients had myocardial ischaemia. SDSs in patients with myocardial ischaemia and those without were 3.5 ± 1.8 and 0.4 ± 0.5, respectively (p < 0.001). PFRs after stress (r = −0.22, p = 0.02) and at redistribution (r = −0.24, p = 0.01) were inversely correlated with SDS. Multivariate logistic regression analysis showed that PFR at redistribution was an independent predictor of the presence of myocardial ischaemia in patients with non-obstructive CAD (odds ratio: 0.15, 95% confidence interval: 0.04–0.51, p = 0.002).Conclusion: Our data suggest that PFR, the index of LV diastolic function from ECG-gated SPECT, helps to find myocardial ischaemia in patients with non-obstructive CAD.

'Comparison of Automated Quantification and Semi quantitative Visual Analysis Findings of IQ-SPECT MPI with Conventional Coronary Angiography in Patients with Stable Angina

The aim of this study was to assess the validity of automated quantitative and semiquantitative visual analysis of total perfusion deficit (TPD) using the IQ SPECT gamma camera system compared to conventional coronary angiographically detected significant coronary artery disease (CAD). The study included patients with suspected CAD who underwent myocardial perfusion single photon emission computed tomography and conventional coronary angiography. The summed stress score (SSS), summed rest score (SRS), and summed difference score (SDS) (semiquantitative visual analysis results) were assessed using a 5-point scale in a standard 17-segment model, and TPD (stress, rest, and ischemic TPD) was quantified using automated software. In all, 84 patients (Group 1, those who underwent revascularization) had significant coronary artery lesions, and 81 (Group 2) had non-significant lesions. The median interquartile range values were: stress-TPD (sTPD): 16 (3.5- 33.5) vs 9.2 (2-17.9), rest-TPD: 9.4 (2.2-18.8) vs 4 (1-11), and 6.9 (1.9-14.1) vs 3.4 (1-6.1) for ischemic-TPD (iTPD) in Group 1 and Group 2, respectively. To detect ischemia, the optimal cut-off points were 9.5 (sensitivity: 75%, specificity; 60%) for sTPD, and 4.5 (sensitivity: 56%, specificity: 73%) for iTPD. There were significant correlations between quantitative and semi-quantitative methods in detection of significant coronary artery disease (sTPD-SSS: r=0.954, sTPD-SDS: r=0.746, iTPD-SSS: r=0.654, iTPD-SDS: r=0.759; p<0.05 for all). The quantitative analysis and summed stress scores produced by the IQ SPECT system appear to be a useful and valid method to detect significant CAD.

Risk factors of non-sustained ventricular tachycardia by technetium-perfusion imaging in patients with coronary artery lesions caused by Kawasaki disease

BackgroundSudden death can occur in some patients with non-sustained ventricular tachycardia (NSVT) after myocardial infarction (MI) in those with coronary artery lesions (CAL) caused by Kawasaki disease (KD). The aim of this study was to determine the risk factors for NSVT in the late period after KD by technetium-99m-tetrofosmin myocardial perfusion imaging (MPI). MethodsWe retrospectively analyzed the relation between the appearance of NSVT and the findings in MPI single-photon-emission computed tomography (SPECT) in 75 patients (55 males and 20 females) who had had CAL caused by KD. All the patients had undergone MPI and 24-h Holter electrocardiogram at the same time between 2003 and 2012. The age at MPI ranged from 2 to 44 years (median 19 years), and the time from the onset of KD to MPI ranged from 1 to 44 years (median 18 years). We evaluated extent score (ES), summed rest score (SRS), summed stress score (SSS), summed difference score (SDS), and left ventricular ejection fraction (LVEF) by quantitative gated SPECT software. We analyzed which factors related to NSVT using multivariate logistic regression. Further, we calculated the cut-off point for NSVT using receiver operating characteristic curve. ResultsThe affecting factors were ES (OR, 0.63, 95%CI, 0.35–0.92, p=0.013) and the interval from the onset of KD to MPI (OR, 0.82, 95%CI, 0.69–0.96, p=0.004). The cut-off points for ES and the interval from the onset of KD were 11% (AUC, 0.931, p<0.001) and 18 years (AUC, 0.732, p=0.007), respectively. ConclusionsES is the strongest parameter for predicting NSVT in the late period. In patients with post-KD, adolescence and young adults with ES ≥11% are at risk of fatal ventricular arrhythmia.

Ischemic burden assessment of myocardial perfusion CT, compared with SPECT using semi-quantitative and quantitative approaches

BackgroundWe aimed to compare the myocardial ischemic burden assessed using semi-quantitative and quantitative analysis of computed tomography-myocardial perfusion imaging (CT-MPI) with that of single-photon emission computed tomography (SPECT). MethodsFrom 2011 to 2013, 97 patients who underwent CT-MPI and SPECT were evaluated. The extent and severity of perfusion defects were assessed on a 5-point scale using a standard 16-segment model, and were expressed as summed stress score (SSS) and summed difference score (SDS). Receiver operating characteristic (ROC) curves for quantitative parameters were generated for the diagnosis of abnormal perfusion defect (SSS ≥ 4) and presence of ischemia (SDS ≥ 2) on SPECT. ResultsOn CT-MPI, 298 (19.2%) of the 1552 segments showed perfusion abnormalities during stress, whereas perfusion abnormalities were shown in 179 (11.5%) segments on SPECT-MPI. On a per-person basis, there was good agreement, with intraclass correlation coefficients of 0.78 for SSS and 0.72 for SDS. A significant reduction of attenuation in stress and myocardial perfusion reserve index, along with an increase in % defect volume of CT-MPI, were demonstrated as the degree of perfusion defect or ischemia on SPECT increased. On the ROC curves, % defect volume on CT-MPI demonstrated the highest area under the curve: 0.91 for abnormal perfusion defect and 0.89 (all p < 0.001) for the presence of ischemia on SPECT. ConclusionsSemi-quantitative analysis of CT-MPI showed good accordance with SPECT. A quantitative approach for CT-MPI, especially % defect volume, may provide additional value in the identification of myocardial perfusion abnormalities.Clinical Trial Registration:https://clinicaltrials.gov/ct2/show/NCT01696006.

Left ventricular dyssynchrony and abnormalities in wall motion, assessed by gated-SPECT as ischemic auxiliary markers

IntroductionLeft ventricular dyssynchrony (LVD) quantified by gated myocardial perfusion studies (MPS), through phase analysis (PA), has shown controversial results in myocardial stunning. ObjectivesAssessment of LVD and regional wall motion abnormalities (RWMA) in normal and ischemic patients. MethodsA cohort of 172 patients were studied. Summed Stress Score (SSS), Summed Resting Score (SRS), and Summed Difference Score (SDS) were evaluated. Group 1-patients with normal MPS (N = 133) and Group 2-patients with myocardial ischemia in the MPS (N = 39). LVD was evaluated through PA and RWM by visual analysis. ResultsSSS 0 vs 9.8 ± 3.9 P = .0001; SDS 0 vs 9.8 ± 3.9 P = .0001; SRS 0 vs 0 P = NS, in G1 and G2. Significant differences were found in LVD between G1 and G2, bandwidth 36 ± 14 vs 63 ± 46 P = .0001; standard deviation 16 ± 10 vs 26 ± 15 P = .0001. In G1, 16% had LVD vs RWMA in 0%, P = .0001 and in G2, 59% with LVD vs 33% with RWMA, P = .03. Sensitivity for LVD 59% and for RWMA 33%, P = .03 and specificity for LVD 83% and for RWMA 100%, P = .0001. ConclusionIschemic patients have LVD post-stress due to myocardial stunning. LVD measured by PA could be a useful tool to identify ischemia.

Myocardial Perfusion Abnormalities in Young and Premenopausal Women with Systemic Lupus Erythematosus, Detected with 99MTC MIBI Myocardial Perfusion Scintigraphy - Prevalence and Correlation with Proatherogenic Factors.

Atherosclerosis in young and premenopausal women with systemic lupus erythematosus (SLE) is frequent, premature and progressive. Although asymptomatic or with atypical clinical presentation, the patients are at high risk of cardiac events. Aim of this study is to estimate the risk profile for atherogenesis and the prevalence of myocardial perfusion abnormalities with 99mTc myocardial perfusion scintigraphy (MPS) in young and premenopausal women. Sixty female patients, aged 30-72 years (divided into two subgroups - patients under 45 years of age and patients over 45 years), diagnosed with SLE for over of 5 years, in active phase of the disease were analyzed for disease activity scores (SLEDAI), the immunologic status of the disease (ANA and a-DNA antibodies in the serum), procoagulant tendency (antiphospholipid antibodies-APhL and lupus-anticoagulant-LAC), the activity of the inflammatory process (hsCRP), the anti-SLE therapeutic approach and the presence of traditional risk factors for atherosclerosis (BMI, smoking, hypertension, hyperlipidemia, diabetes, and familial history for the CAD). Using one-day Dipyridamol - Rest 99mTc SPECT Gated MPS SPECT the extent, severity and reversibility of myocardial perfusion abnormalities were estimated, along with summed scores at stress, rest and summed difference scores and left ventricle volumes and ejection fraction. Abnormal MPS SPECT were detected in 27/60 or in 45% of patients, with one vessel affection of 66.7% (18/27pts) of LAD and 14.8% (4/27pts) o RCA and with two vessel disease of LAD/RCA in 2/27 pts (7.4%) and LAD/Cx in 3/27pts (11.1%). Myocardial perfusion abnormalities were equally prevalent in subgroups of patients younger than 45 years (44,4%) and in patients older than 45 years (45.5%) (ns). The subgroups did not differ significantly concerning the extent of perfusion abnormalities (9,8±3.2% of LV myocardial mass vs. 9,8±7.1%,ns), their severity (with predominance of mild perfusion defects, 48,6% vs. 51,3%,ns) and reversibility (reversible in 41.3% and 58.6%, ns). The differences between the summed scores of severity and the extent of ischemia in the two subgroups were statistically nonsignificant. Younger patients had significantly higher end-diastolic, end-systolic and stroke volumes during stress and rest conditions, compared to older patients (p<0,01) although there were no differences in systolic function, which was not affected in either of the groups as expressed threw ejection fraction. Although nonsignificant, younger patients had higher values of hsCRP and higher procoagulant activity (positive aPhL, LAC) while they were with more active disease activity, with higher SLEDAI score compared to older patients (p=0.028). Higher SLEDAI score and LV volumes, especially EDV at stress were identified as predictor of abnormal MPS in younger groups and more aggressive multidrug anti SLE treatment as predictor of normal MPS. The prevalence and characteristics of myocardial perfusion abnormalities in young SLE are equal as the same in older SLE patients, which indicates the presence of premature, accelerated atherosclerosis in young cohort of patients with SLE. Younger SLE patients with pure disease control (higher SLEDAI score, less aggressive treatment, high hsCRP values and pronounced procoagulant tendency) should undergo screening for myocardial perfusion abnormalities s using 99mTc MIBI MPS).

Minimal rest activity for SPECT myocardial perfusion imaging in a one-day stress-first protocol.

Guidelines propose different rest-stress activity ratios (RSAR) for one-day stress-first SPECT myocardial perfusion imaging (MPI), but evidence is limited. Our aim was to determine and validate the minimal RSAR resulting in the same diagnostic outcome in one-day stress-first SPECT MPI. Forty-seven patients referred for rest after stress CZT-SPECT/CT MPI were prospectively included. Rest acquisitions were performed 3h after stress. In addition to the stress and rest acquisitions, the first 22 patients underwent an additional acquisition prior to the rest injection to determine the remaining stress activity. Next, we simulated six RSARs varying from 1.0 to 3.5 in both patients and a phantom and compared the images to those using the reference RSAR of 4.0. Differences in summed difference score (SDS) >2 or ischemic defect interpretation were considered to significantly influence diagnostic outcome. After deriving the minimal RSAR, it was validated in 25 additional patients by comparing it to a RSAR of 4.0. After 3h only 26% of the stress activity was still present in the myocardium. SDS differences >2 were found in one (4%) patient using RSAR of 3.5, 2.5 and 2.0, in three (12%) using 1.5 and in five (20%) using SRAR of 1.0. These results were consistent with the phantom study showing SDS differences >2 for RSARs ≤1.5 and with the visual interpretation which showed an increased number of deviating scans for RSAR 1.0. Validating the RSAR of 2.0 resulted in a different SDS in one patient (SDS of 30 versus 11). Moreover, two scans were interpreted as ischemic instead of normal when using RSAR 2.0 and in two other scans the opposite was the case. A RSAR of 2.0 in one-day stress-first MPI SPECT seems sufficient to obtain accurate diagnostic outcomes and is therefore recommended to reduce radiation exposure.

Referral to coronary angiography post myocardial perfusion imaging

The current guidelines for CAD suggest that patients with moderate to severe ischemia should be referred for angiography and possible revascularization, while patients with mild ischemia can be safely treated medically. These recommendations are currently being tested in the ISCHEMIA trial. It is unclear how often patients with moderate to severe ischemia are referred to coronary angiography. The aim of this study is to identify the rate and predictors of referral to coronary angiography post MPI. A retrospective cohort study included patients with suspected or known CAD who were referred to PET-CT imaging MPI due various clinical indications between May 2011 and March 2017. Ischemic burden was measured by the sum difference score. Moderate to severe ischemia was defined by summed stress score more than 7. A total of 5060 patients were included. Approximately, one third of patients had prior coronary disease. The prevalence and extent of ischemia was higher among patients with previous coronary disease. Chest pain or shortness of breath was the most common indication for referral to MPI. Patients who had severe ischemia, nearly 70% of them were referred to coronary angiography within 90 days and 76.6% were referred to coronary angiography within one year. However patients with moderate ischemia were much less often referred to coronary angiography and less than half of these patients were referred to coronary angiography within 90 days. The independent predictors of referral to coronary angiography within 90 days among all patients were age, CAD, transient ischemic dilation and presence and degree of ischemia. This study found that the increase in patient’s age, Summed Different Score, Transient Ischemic Dilation, ischemia group, and having CAD can predict an increased in the coronary angiography referral, and CVA is a protective factor for referral to coronary angiography.

The effect of time-of-flight and point spread function modeling on 82Rb myocardial perfusion imaging of obese patients

BackgroundThe effect of time-of-flight (TOF) and point spread function (PSF) modeling in image reconstruction has not been well studied for cardiac PET. This study assesses their separate and combined influence on 82Rb myocardial perfusion imaging in obese patients. MethodsThirty-six obese patients underwent rest-stress 82Rb cardiac PET. Images were reconstructed with and without TOF and PSF modeling. Perfusion was quantitatively compared using the AHA 17-segment model for patients grouped by BMI, cross-sectional body area in the scanner field of view, gender, and left ventricular myocardial volume. Summed rest scores (SRS), summed stress scores (SSS), and summed difference scores (SDS) were compared. ResultsTOF improved polar map visual uniformity and increased septal wall perfusion by up to 10%. This increase was greater for larger patients, more evident for patients grouped by cross-sectional area than by BMI, and more prominent for females. PSF modeling increased perfusion by about 1.5% in all cardiac segments. TOF modeling generally decreased SRS and SSS with significant decreases between 2.4 and 3.0 (P < .05), which could affect risk stratification; SDS remained about the same. With PSF modeling, SRS, SSS, and SDS were largely unchanged. ConclusionTOF and PSF modeling affect regional and global perfusion, SRS, and SSS. Clinicians should consider these effects and gender-dependent differences when interpreting 82Rb perfusion studies.

Accuracy of cadmium-zinc-telluride imaging in detecting single and multivessel coronary artery disease: Is there any gender difference?

PurposeTo evaluate gender-related differences in diagnostic accuracy of cadmium‑zinc-telluride (CZT) myocardial perfusion imaging in detecting single- and multi-vessel coronary artery disease (CAD). MethodsWe prospectively enrolled 1161 consecutive patients with known or suspected coronary artery disease (288, 25% women and 873, 75% men) who had been referred to our laboratory for stress–rest myocardial perfusion imaging (single-day stress–rest protocol, mean radiation dose: 4 mSv). All patients underwent coronary angiography within 30 days; significant CAD was defined in the presence of a coronary stenosis >70%. Summed stress scores (SSS), summed rest scores (SRS) and summed difference scores (SDS) were obtained. Image quality was graded “good” or better in >90% of patients. ResultsOn coronary angiography, left main trunk, left anterior descending artery, left circumflex artery and right coronary artery obstructive stenosis were seen in 13, 486, 393 and 499 patients, respectively. Global SSS was the best predictor of CAD in women (AUC = 0.866, 81% sensitivity and 79% specificity) and in men (AUC = 0.871, 76% sensitivity and 84% specificity). Interestingly, its accuracy was maintained also in patients with two-vessel (women: AUC = 0.842, p < 0.001; men: AUC 0.839, p < 0.001) or three-vessel disease (women: AUC = 0.800, p < 0.001; men: AUC 0.804, p < 0.001). There was no gender-related difference in terms of diagnostic accuracy. ConclusionsEvaluation of multivessel disease can be obtained by CZT camera in men as well as in women, with high accuracy at a lower radiation exposure.

Comparative Effectiveness of CT-Derived Atherosclerotic Plaque Metrics for Predicting Myocardial Ischemia

ObjectivesThis study sought to investigate the performance of various cardiac computed tomography (CT)–derived atherosclerotic plaque metrics for predicting provocable myocardial ischemia. BackgroundThe association of coronary arterial diameter stenosis with myocardial ischemia is only modest, but cardiac CT provides several other, readily available atherosclerosis metrics, which may have incremental value. MethodsThe study analyzed 873 nonstented coronary arteries and their myocardial perfusion territories in 356 patients (mean 62 years of age) enrolled in the CORE320 (Coronary Artery Evaluation using 320-row Multidetector Computed Tomography Angiography and Myocardial Perfusion) study. Myocardial perfusion defects in static CT perfusion imaging were graded at rest and after adenosine in 13 myocardial segments using a 4-point scale. The summed difference score was calculated by subtracting the summed rest score from the summed stress score. Reversible ischemia was defined as summed difference score ≥1. In a sensitivity analysis, results were also provided using single-photon emission computed tomography (SPECT) as the reference standard. Vessel based predictor variables included maximum percent diameter stenosis, lesion length, coronary calcium score, maximum cross-sectional calcium arc, percent atheroma volume (PAV), low-attenuation atheroma volume, positive (external) vascular remodeling, and subjective impression of “vulnerable plaque.” The study used logistic regression models to assess the association of plaque metrics with myocardial ischemia. ResultsIn univariate analysis, all plaque metrics were associated with reversible ischemia. In the adjusted logistic model, only maximum percent diameter stenosis (1.26; 95% confidence interval: 1.15 to 1.38) remained an independent predictor. With SPECT as outcome variable, PAV and “vulnerable” plaque remained predictive after adjustment. In vessels with intermediate stenosis (40% to 70%), no single metric had clinically meaningful incremental value. ConclusionsVarious plaque metrics obtained by cardiac CT predict provocable myocardial ischemia by CT perfusion imaging through their association with maximum percent stenosis, while none had significant incremental value. With SPECT as reference standard, PAV and “vulnerable plaque” remained predictors of ischemia after adjustment but the predictive value added to stenosis assessment alone was small.