Stress Myocardial Perfusion SPECT Research Articles

The preoperative myocardial perfusion and internal mammary artery graft blood flow relationship in patients with ischemic cardiomyopathy

Objective. The purpose of this study was to determine the association between preoperative myocardial perfusion data (obtained by SPECT) with transit time blood flow characteristics in left internal mammary artery (LIMA) to left anterior descending artery (LAD) grafts in patients with ischemic cardiomyopathy.Methods. The study group consisted of 57 patients with ischemic cardiomyopathy. Intraoperative transit-time flow measurement (TTFM) of LIMA-LAD grafts were performed in all patients. All patients were also examined with preoperative stress and rest myocardial perfusion SPECT with 99m Tc-MIBI. Anastomotic patency was considered satisfactory with a normal waveform of blood flow, diastolic-dominant blood filling, and a mean flow value greater than 11.5 ml/min.Results. All 57 patients with LIMA-LAD grafts were divided into two groups; those with graft satisfactory patency (n = 40) and those with unsatisfactory patency (n = 17) as determined by TTFM. We found differences among these groups in values of global summed rest score (20.7 ± 7.5 vs. 29.8 ± 4.0; p = 0.002), global total perfusion deficit (TPD) at rest (32.0 ± 11.4 vs. 43.0 ± 7.2; p = 0.01), and regional TPD at rest in the LAD territory (20.7 ± 7.5 vs. 29.8 ± 4.0; p = 0.002). Additionally, the flow characteristics were different in patients with and without surgical left ventricle reconstruction (Q (ml/min): 17 (11.5, 40.8) vs. 47 (25, 69.5), p = 0.013; PI: 3.9 (3.2, 7.4) vs. 2.4 (2.0, 3.6), p = 0.001; DF (%): 63.5 (44.5, 70.8) vs. 74 (66.0, 79.7), p = 0.019). TPD at rest was the best predictor of the LIMA-LAD graft satisfactory: area under curve = 0.771, cut-off value = 26.85 with 83.3% sensitivity and 78.1% specificity.Conclusions. Preoperative myocardial perfusion characteristics are associated with blood flow in LIMA-LAD graft in patients with ischemic cardiomyopathy. TPD at rest (assessed globally and in the LAD region) as well as global SRS value are potential predictors of early graft failure.

First validation of stress myocardial perfusion scintigraphy using a novel reconstruction process.

A new image reconstruction process termed the MUS method (masking process on unsmoothed images) was developed to eliminate artifacts, especially those in the inferior wall. We compared diagnostic performance between the MUS and conventional method in stress myocardial perfusion SPECT (MPS). Enrolled were 126 patients who underwent stress-rest MPS with 99m Tc-MIBI. Patients were divided into two groups: 91 with < 50% stenosis in the RCA or LCX (non-ischemia group) and 35 patients with ≥ 90% stenosis or FFR-positive in the RCA (ischemia group), according to coronary CT or coronary angiography within 3months of MPS. Ischemic heart disease (IHD) was considered positive when the summed difference score of five segments corresponding to the inferior wall region was ≥ 2. Sensitivity was comparable between the MUS method and the conventional method (ordered subset expectation maximization; OSEM) (51% vs 54%, respectively; (p = 0.366), specificity was significantly higher using the MUS method (87% vs 77%, respectively; p < 0.05), and diagnostic performance was higher using the MUS method (area under curve [AUC], conventional 0.61 vs. MUS 0.69, p = 0.138). In evaluation of 87 patients after excluding 39 who received additional prone imaging, sensitivity using the MUS method was 44%, which was comparable to 44% using the conventional method but specificity was 90%, which was significantly higher than 77% using the conventional method (p < 0.05). The diagnostic performance of the MUS method was higher (AUC, conventional 0.60 vs. MUS 0.67, p = 0.185). Use of the MUS method improved specificity in diagnosis of IHD while maintaining sensitivity, compared with the conventional method. The MUS method can achieve an improvement in diagnostic accuracy equivalent to the supine position, particularly in patients who have difficulty performing the prone position, without increasing the patient burden.

Safety and Feasibility of Dynamic 6-Minute Adenosine Stress Myocardial Perfusion SPECT Imaging in Patients Diagnosed With Severe Aortic Valve Stenosis

Safety and Feasibility of Dynamic 6-Minute Adenosine Stress Myocardial Perfusion SPECT Imaging in Patients Diagnosed With Severe Aortic Valve Stenosis

"Virtual" attenuation correction: improving stress myocardial perfusion SPECT imaging using deep learning.

Myocardial perfusion imaging (MPI) using single-photon emission computed tomography (SPECT) is widely used for coronary artery disease (CAD) evaluation. Although attenuation correction is recommended to diminish image artifacts and improve diagnostic accuracy, approximately 3/4ths of clinical MPI worldwide remains non-attenuation-corrected (NAC). In this work, we propose a novel deep learning (DL) algorithm to provide "virtual" DL attenuation-corrected (DLAC) perfusion polar maps solely from NAC data without concurrent computed tomography (CT) imaging or additional scans. SPECT MPI studies (N = 11,532) with paired NAC and CTAC images were retrospectively identified. A convolutional neural network-based DL algorithm was developed and trained on half of the population to predict DLAC polar maps from NAC polar maps. Total perfusion deficit (TPD) was evaluated for all polar maps. TPDs from NAC and DLAC polar maps were compared to CTAC TPDs in linear regression analysis. Moreover, receiver-operating characteristic analysis was performed on NAC, CTAC, and DLAC TPDs to predict obstructive CAD as diagnosed from invasive coronary angiography. DLAC TPDs exhibited significantly improved linear correlation (p < 0.001) with CTAC (R2 = 0.85) compared to NAC vs. CTAC (R2 = 0.68). The diagnostic performance of TPD was also improved with DLAC compared to NAC with an area under the curve (AUC) of 0.827 vs. 0.780 (p = 0.012) with no statistically significant difference between AUC for CTAC and DLAC. At 88% sensitivity, specificity was improved by 18.9% for DLAC and 25.6% for CTAC. The proposed DL algorithm provided attenuation correction comparable to CTAC without the need for additional scans. Compared to conventional NAC perfusion imaging, DLAC significantly improved diagnostic accuracy.

CRT-700.08 Safety and Feasibility of Dynamic 6-Minute Adenosine Stress Myocardial Perfusion SPECT Imaging in Patients Diagnosed With Severe Aortic Valve Stenosis

CRT-700.08 Safety and Feasibility of Dynamic 6-Minute Adenosine Stress Myocardial Perfusion SPECT Imaging in Patients Diagnosed With Severe Aortic Valve Stenosis

Simulating dose reduction for myocardial perfusion SPECT using a Poisson resampling method.

The purpose of this study was to determine the lowest Tl-201 dose that does not reduce the image quality of myocardial perfusion SPECT (MPS) by Poisson resampling simulation. One hundred and twelve consecutive MPS data from patients with suspected or known coronary artery disease were collected retrospectively. Stress and rest MPS data were resampled using the Poisson method with 33%, 50%, 67%, and 100% count settings. Two nuclear medicine physicians assessed the image quality of reconstructed data visually by giving grades from - 2 to + 2. The summed stress score (SSS), summed rest score (SRS), and summed difference score (SDS) were obtained on the workstation. Image quality grades and semi-quantitative scores were then compared among these resampled images. The proportions of "adequate" image quality were 0.48, 0.75, 0.92, and 0.96 for the groups of images with 33%, 50%, 67%, and 100% data, respectively. The quality of the resampled images was significantly degraded at 50% and 33% count settings, while the image quality was not different between 67 and 100% count settings. We also found that high body mass index further decreased image quality at 33% count setting. Among the semi-quantitative parameters, SSS and SRS showed a tendency to increase with a decline in count. Based on the simulation results, Tl-201 dose for MPS can be reduced to 74MBq without significant loss of image quality. However, the SSS and SRS can be changed significantly, and it needs to be further verified under the different conditions.

Clinical usefulness of quantification of myocardial blood flow and flow reserve using CZT-SPECT for detecting coronary artery disease in patients with normal stress perfusion imaging

BackgroundRelative myocardial perfusion imaging can misdiagnose “balanced” ischemia caused by coronary artery disease (CAD). We assessed the feasibility of myocardial blood flow (MBF) and myocardial perfusion reserve (MPR) using dynamic single-photon emission computed tomography (SPECT) with a cadmium-zinc-telluride (CZT) camera for estimating underlying CAD in patients with normal stress myocardial perfusion SPECT (MPS). Methods125 patients with normal stress MPS (summed stress score ≤3) were enrolled. All patients underwent coronary angiography (CAG) and stress/rest 201Tl dynamic SPECT for MBF and MPR calculation. The diagnostic accuracy of both these quantitative values and other clinical risk factors for predicting occult CAD were validated by CAG. ResultsMPR was 2.85 in patients with no CAD, 2.47 with 1-, 1.98 with 2-, and 1.76 with 3-vessel CAD. The patient’s age, morbidity of diabetes mellitus (DM), chronic kidney disease (CKD), stress MBF, and MPR were significantly associated with the presence of CAD (age, p=0.02; DM, p=0.005; CKD, p=0.005; creatinine level, p= 0.012, stress MBF, p=0.019, and MPR, p<0.001). Independent predictors in the multivariate regression analysis were as follows: DM, p=0.011, CKD, p=0.028, and MPR, p<0.001. The combined index was calculated from three independent predictors. Area under the receiver operating characteristic curve was 0.75 for MPR and 0.81 for the combined index. To identify CAD, sensitivity, and specificity for MPR were 77% and 66%, and for the combined index they were 79% and 66%, respectively. ConclusionQuantification of MPR and MBF using dynamic SPECT with a CZT camera can be useful to identify balanced ischemia caused by occult CAD in patients with normal stress MPS findings.

Myocardial Perfusion SPECT 2018 in Germany: Results of the 8th Survey.

This paper presents the results of the 8th survey of myocardial perfusion SPECT (MPS) from the reporting year 2018. 291 questionnaires (184 practices (PR), 77 hospitals (HO), 30 university hospitals (UH)) were evaluated. Results of the last survey from 2015 are set in squared brackets. MPS of 145 930 [121 939] patients were reported (+ 19.6 %). 76 % [78 %] of all patients were studied in PR, 16 % [14 %] in HO, and 8 % [8 %] in UH, mostly with a 2-day-protocol 48 % [50 %]. 99.96 % [98 %] of all MPS were performed with Tc-99 m radiopharmaceuticals and in 0.04 % with Tl-201.A pharmacological stress test was applied in 49 % [43 %] (23 % [22 %] adenosine, 26 % [20 %] regadenoson, dipyridamole or dobutamine together < 1 % [1 %]). Attenuation correction was performed in 26 % [25 %] of all MPS, gated SPECT in 86 % [80 %] of stress MPS, in 87 % [78 %] of rest and in 83 % [76 %] of all stress and rest MPS. 67 % [53 %] of the departments performed MPS scoring by default, whereas 16 % [24 %] did not apply this feature at all.69 % [60 %] reported an increase or no changes in their MPS patient numbers. One hundred twenty-six departments which participated in the surveys from 2009 to 2018 reported an increase in MPS by 44 %. 69 % [70 %] of the MPS were requested by ambulatory care cardiologists. The 2018 MPS survey reveals a high-grade adherence of routine MPS practice to current guidelines. The positive development in MPS performance and MPS numbers observed since 2012 remains ongoing.

Comparison of diagnostic accuracy of stress myocardial perfusion imaging for detecting hemodynamically significant coronary artery disease between cardiac magnetic resonance and nuclear medical imaging: A meta-analysis

AimsThis study aimed to compare the diagnostic accuracy of stress myocardial perfusion imaging between cardiac magnetic resonance (CMR) and nuclear medical imaging, including single-photon emission computed tomography (SPECT) and positron emission tomography (PET), for the diagnosis of hemodynamically significant coronary artery disease (CAD) with fractional flow reserve (FFR) as the reference standard. Methods and resultsWe searched PubMed and Embase for all published studies that evaluated the diagnostic accuracy of stress myocardial perfusion imaging modalities, including CMR, SPECT, and PET, to diagnose hemodynamically significant CAD with FFR as the reference standard. A total of 28 articles met the inclusion criteria and were included in the meta-analysis: 14 CMR, 13 SPECT, and 5 PET articles. The results demonstrated a pooled sensitivity of 0.88 (95% confidence interval [CI]: 0.80–0.93), 0.69 (95% CI: 0.56–0.79), and 0.83 (95% CI: 0.70–0.91), and a pooled specificity of 0.89 (95% CI: 0.85–0.93), 0.85 (95% CI, 0.80–0.89), and 0.89 (95% CI, 0.86–0.91) for CMR, SPECT, and PET, respectively. The area under the curve (AUC) of CMR, PET, and SPECT was 0.94 (95% CI, 0.92–0.96), 0.92 (95% CI, 0.89–0.94), and 0.87 (95% CI, 0.83–0.89), respectively. ConclusionsCMR and PET both have high accuracy and SPECT has moderate accuracy to detect hemodynamically significant CAD with FFR as the reference standard. Furthermore, the diagnostic accuracy of CMR at 3.0 T is superior to 1.5 T.

P298Relevance of transient ischemic dilatation in elderly patients with comorbidities undergoing stress myocardial perfusion SPECT imaging

P298Relevance of transient ischemic dilatation in elderly patients with comorbidities undergoing stress myocardial perfusion SPECT imaging

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.

Abstract 8: Association Between Abnormalities in Myocardial Perfusion and Patient-reported Angina Among Patients With Known Coronary Artery Disease: PET vs. SPECT Comparison

Background: Although the burden of angina would be expected to be intricately linked with the degree of myocardial ischemia, prior work with stress echocardiography and SPECT myocardial perfusion imaging (MPI) have shown these two measures to be poorly correlated. We examined the association of positron emission tomography (PET) MPI, which can more accurately characterize myocardial ischemia, with angina. Methods: Patients with known CAD who were referred for a clinically-indicated vasodilator MPI at Saint Luke’s Hospital (Kansas City, MO) were included. All patients underwent both SPECT and PET MPI and completed the Seattle Angina Questionnaire (SAQ) at the time of MPI. SAQ angina frequency (AF) and physical limitation (PL) scores were compared across the spectrum of ischemic burden (no ischemia, &lt;5, 5-10 and &gt;10% ischemic myocardium) with PET and SPECT. Results: Among 322 patients with CAD undergoing MPI (mean age 66.3 ± 9.7 years; 64.9% men), mean SAQ AF and PL scores were 78.5 ± 19 and 83.3 ± 19.8, respectively. A total of 72 patients (44.7%) with PET and 67 (41.6%) with SPECT had at least mild ischemia on MPI. There was no association with burden of angina by SAQ AF or PL scores and degree of ischemia by PET or SPECT MPI (Figure). Conclusion: We found no association between patient-reported angina and the burden of ischemia, regardless of the modality used. These findings suggest that other complex, multi-system pathways likely impact perception of pain and description of angina in patients with CAD, and that direct measurement of patient-reported symptoms needs to supplement physiologic assessment of ischemia.

Incidental spade-shaped FDG uptake in the left ventricular apex suggests apical hypertrophic cardiomyopathy.

Apical wall thickening with an "ace-of-spades" configuration is a unique sign of apical hypertrophic cardiomyopathy (AHCM). We investigated spade-shaped FDG uptake around the left ventricular apex (SSUA) incidentally found in routine oncological FDG PET. Cases showing SSUA were selected based on retrospective review. The pattern or intensity of SSUA was compared with the results of electrocardiogram (ECG), echocardiography, and stress myocardial perfusion SPECT. The diagnosis of ACHM was based on the presence of giant negative T wave in ECG, thickness of spade-shaped hypertrophy in the apex in echocardiography, and increased tracer uptake in the apex in rest SPECT. Among the 34 patients in 36 PET scans showing SSUA, SSUA was weak in 17 and intense in 17. There were isolated SSUA (n = 29) and SSUA with diffuse or other focal left ventricular uptake (n = 5). Three patients with the latter uptake pattern turned out to have coexistence of AHCM and asymmetric septal hypertrophy. Of the 16 SSUA-positive patients who underwent echocardiography, 13 (81%) were diagnosed as AHCM and the remaining 3 were regarded as borderline AHCM (apical wall thickness, 14-15mm). There were 16 patients with SSUA who also underwent PET scans after the study period among which 11 (69%) had persistent SSUA in the follow-up PET. In the remaining 5, follow-up PET scans showed diffuse left ventricular uptake and SSUA was barely visible. The intensity of SSUA was significantly or marginally associated with giant negative T wave (p < 0.01), apical asynergy (p = 0.08), and impaired coronary flow reserve (p < 0.05). There were no other factors correlated with the pattern or intensity of SSUA. SSUA incidentally found in oncological FDG PET appeared to be associated with AHCM, especially in ischemic conditions. The moderate repeatability of SSUA was probably due to obscurity by physiological uptake.

Myocardial perfusion SPECT 2015 in Germany. Results of the 7th survey.

SummaryAimThe working group Cardiovascular Nuclear Medicine of the German Society of Nuclear Medicine presents the results of the 7th survey of myocardial perfusion SPECT (MPS) of the reporting year 2015.Method268 questionnaires (173 practices [PR], 67 hospitals [HO], 28 university hospitals [UH]) were evaluated. Results of the last survey from 2012 are set in squared brackets.ResultsMPS of 121 939 [105 941] patients were reported. 98 % [95 %] of all MPS were performed with Tc-99m radiopharmaceuticals and 2 % [5 %] with Tl-201. 78 % [79 %] of all patients were studied in PR, 14 % [15 %] in HO, and 8 % [6 %] in UH. A pharmacological stress test was performed in 43 % [39 %] (22 % [24 %] adenosine, 20 % [9 %] regadenoson, 1% [6 %] dipyridamole or dobutamine). Attenuation correction was applied in 25 % [2009: 10 %] of MPS. Gated SPECT was performed in 78 % [70 %] of all rest MPS, in 80 % [73 %] of all stress and in 76 % [67 %] of all stress and rest MPS. 53 % [33 %] of all nuclear medicine departments performed MPS scoring by default, whereas 24 % [41 %] did not apply any quantification. 31 % [26 %] of all departments noticed an increase in their counted MPS and 29 % [29 %] no changes. Data from 89 departments which participated in all surveys showed an increase in MPS count of 11.1 % (PR: 12.2 %, HO: 4.8 %, UH: 18.4 %). 70 % [60 %] of the MPS were requested by ambulatory care cardiologists.ConclusionThe 2015 MPS survey reveals a high-grade adherence of routine MPS practice to current guidelines. The positive trend in MPS performance and number of MPS already observed in 2012 continues. Educational training remains necessary in the field of SPECT scoring.

High Concordance Between Mental Stress-Induced and Adenosine-Induced Myocardial Ischemia Assessed Using SPECT in Heart Failure Patients: Hemodynamic and Biomarker Correlates.

Mental stress can trigger myocardial ischemia, but the prevalence of mental stress-induced ischemia in congestive heart failure (CHF) patients is unknown. We characterized mental stress-induced and adenosine-induced changes in myocardial perfusion and neurohormonal activation in CHF patients with reduced left-ventricular function using SPECT to precisely quantify segment-level myocardial perfusion. Thirty-four coronary artery disease patients (mean age±SD, 62±10 y) with CHF longer than 3 mo and ejection fraction less than 40% underwent both adenosine and mental stress myocardial perfusion SPECT on consecutive days. Mental stress consisted of anger recall (anger-provoking speech) followed by subtraction of serial sevens. The presence and extent of myocardial ischemia was quantified using the conventional 17-segment model. Sixty-eight percent of patients had 1 ischemic segment or more during mental stress and 81% during adenosine. On segment-by-segment analysis, perfusion with mental stress and adenosine were highly correlated. No significant differences were found between any 2 time points for B-type natriuretic peptide, tumor necrosis factor-α, IL-1b, troponin, vascular endothelin growth factor, IL-17a, matrix metallopeptidase-9, or C-reactive protein. However, endothelin-1 and IL-6 increased, and IL-10 decreased, between the stressor and 30 min after stress. Left-ventricular end diastolic dimension was 179±65 mL at rest and increased to 217±71 after mental stress and 229±86 after adenosine (P<0.01 for both). Resting end systolic volume was 129±60 mL at rest and increased to 158±66 after mental stress (P<0.05) and 171±87 after adenosine (P<0.07), with no significant differences between adenosine and mental stress. Ejection fraction was 30±12 at baseline, 29±11 with mental stress, and 28±10 with adenosine (P=not significant). There was high concordance between ischemic perfusion defects induced by adenosine and mental stress, suggesting that mental stress is equivalent to pharmacologic stress in eliciting clinically significant myocardial perfusion defects in CHF patients. Cardiac dilatation suggests clinically important changes with both conditions. Psychosocial stressors during daily life may contribute to the ischemic burden of CHF patients with coronary artery disease.

State of Overall Cardiovascular Risk and Imaging Strategies in India

Noninvasive cardiac imaging has undergone a recent resurgence in India with the development of new approaches for imaging coronary atherosclerosis. Noncontrast computed tomography (CT) for imaging the extent of coronary artery calcification (CAC) and contrast CT for noninvasive coronary angiography (CTA) are developments with a growing evidence base regarding risk assessment and the diagnosis of obstructive coronary disease. Stress myocardial perfusion SPECT (MPS) is the most commonly used stress imaging technique for patients with suspected or known coronary disease, which is slowly gaining popularity in urban India. In contrast to the nascent evidence noted with coronary CTA, MPS has a robust evidence base, including the support of numerous clinical guidelines. It is likely that assessing the extent of atherosclerosis using CAC or coronary CTA will become an increasing part of mainstream cardiovascular imaging practices.

Value of CACS Compared With ETT and Myocardial Perfusion Imaging for Predicting Long-Term Cardiac Outcome in Asymptomatic and Symptomatic Patients at Low Risk for Coronary Disease: Clinical Implications in a Multimodality Imaging World

ObjectivesThis prospective, observational study in 988 asymptomatic or symptomatic low-risk patients without prior coronary artery disease was conducted to define the relative value of coronary artery calcium score (CACS), exercise treadmill testing (ETT), and stress myocardial perfusion single-photon emission computed tomography (SPECT) variables in predicting long-term risk stratification. BackgroundCACS, ETT, and stress myocardial perfusion SPECT results predict patients' outcome. There are currently no data comparing their relative value in long-term risk stratification. MethodsPatients were stratified by Framingham risk score (FRS), with a median follow-up of 6.9 years. Cardiac events were defined as a composite of cardiac death, nonfatal myocardial infarction, and the need for coronary revascularization. Most patients (87%) were considered appropriate candidates for functional testing as defined by current appropriate use criteria. ResultsThe long-term cardiac event rate was 11.2% (1.6% per year). Multivariate risk predictors in all patients and in the appropriate use cohort were abnormal SPECT (hazard ratio [HR]: 1.83 and 1.99), ETT ischemia (HR: 1.70 and 1.76), decreasing exercise capacity (HR: 1.11 and 1.17), decreasing Duke treadmill score (HR: 1.07 for both), and CACS severity (HR: 1.29 for both), respectively. Throughout the 10-year follow-up, CACS improved risk prediction, with event rates ranging from 0.6% per year (CACS ≤10) to 3.7% per year (CACS >400) (p < 0.0001). CACS also improved risk prediction in all patients, in the appropriate use cohort and among those with low-risk ETT and SPECT results (all, p < 0.001). Area under the receiver-operating characteristic curve was increased when CACS variables (from 0.63 to 0.70; p = 0.01) but not ETT variables (from 0.63 to 0.65) were added to FRS. Moreover, net reclassification improvement was significantly increased when CACS was added to FRS + functional variables in all patients and in the appropriate use cohort (both, p < 0.0001). ConclusionsCACS significantly improved long-term risk stratification beyond FRS, ETT, and SPECT results across the spectrum of clinical risk and importantly even among those who are currently considered appropriate candidates for functional testing or have low-risk functional test results. Our findings support CACS as a first-line test over ETT or SPECT for accurately assessing long-term risk in such patients.

Use of Myocardial Perfusion SPECT for Preoperative Risk Stratification of Non-Cardiac Surgery

It is difficult to assess the likelihood of perioperative cardiac events mainly because of complicated interrelationships between clinical risk and type of surgery. To overcome this problem, The American College of Cardiology/American Heart Association（ACC/AHA）Task Force published guidelines for perioperative cardiovascular evaluation for non-cardiac surgery. The guidelines offer the strategy of preoperative cardiac therapy, operative performance and perioperative management depending on the urgency of surgery, the patient$ s risk factors, findings of cardiac testing and specific surgical considerations. Non-invasive cardiac testing including myocardial perfusion single-photon emission computed tomography（SPECT）is recommended to be used mainly in patients with poor functional capacity, when the results will affect patient treatment and outcomes. In the current review, we summarized the use of stress myocardial perfusion SPECT referring to previous reports and our data, and provided the tips for indication of SPECT in preoperative risk stratification in non-cardiac surgery.

Further evidence for the robustness of regadenoson stress myocardial perfusion SPECT: its predictive value for cardiac events in chronic renal failure

In recent years, regadenoson has increasingly penetrated the clinical market as a novel pharmacologic stress agent for myocardial perfusion imaging (MPI).1 Regadenoson has favourable features such as a rapid onset of vasodilation with sustained action, enabling injection as a slow bolus,1 and a preferable side-effect profile when compared with adenosine due to adenosine A2A receptor subtype selectivity.2 Another advantage is that it can be used in obstructive pulmonary disease, when the traditional agents dypiridamole and adenosine may be unsafe.3 Many studies investigating regadenoson in different risk groups, using various imaging protocols and nuclear tracers, demonstrated safety and efficacy comparable with adenosine for the detection of reversible myocardial perfusion defects.2 More recently, regadenoson, despite its predominantly renal clearance, was also shown to be well tolerated in patients with chronic renal failure (CRF).4 Because CRF patients are generally at a higher risk for cardiovascular events, the value of MPI in this group has been actively investigated in recent years. Using exercise …

Motivation for whole-heart perfusion CMR: a simulation study based on retrospective comparison of the diagnostic performance of 3-slice vs. whole-heart SPECT

Background There is an ongoing debate on the merit of whole-heart 3D CMR perfusion imaging in terms of improving the overall diagnostic accuracy of myocardial perfusion CMR [1]. Whole-heart imaging is technically more challenging [2] and requires a compromise in terms of the spatial resolution [2] and temporal footprint (hence, potentially leading to more instances of artifactual images). The purpose of this work was to evaluate the potential incremental diagnostic value of whole-heart myocardial perfusion imaging compared to 3-slice imaging. The presented results are based on on a simulation of 3-slice imaging with myocardial perfusion SPECT (MPS) in a retrospective quantitative analysis of a large cohort who underwent stress MPS [3,4].