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Keywords: Myocardial perfusion imaging; SPECT (single-photon emission computed tomography); Quality; Appropriate use; Coronary artery disease; Ischemia EN Myocardial perfusion imaging SPECT (single-photon emission computed tomography) Quality Appropriate use Coronary artery disease Ischemia 864 907 44 04/26/23 20230401 NES 230401 Supplementary Information The online version contains supplementary material available at https://doi.org/10.1007/s12350-022-03162-7. Patient-centered imaging B Background: b Recently, professional societies have recognized the need to develop imaging protocols that are adaptable to a patient's specific need.[76],[77] Specifically, protocols should be adaptable to increase the administered radionuclide dosage when patients have a higher body mass index (BMI) and reduce that dose for lower BMI patients. B Definition of measure: b I Use of patient-centered SPECT MPI protocols. i Confirm the site has written protocols for modifying the imaging protocol for specific populations: Using different patient doses or variable acquisition times for low and high BMI patients. Literature demonstrates that attenuation mitigation strategies improve the normalcy rate of stress-first imaging.[88]-[90] B Definition of measure: b I Percentage of Tc-99m stress SPECT MPI studies performed with stress-only imaging. i B Rationale for inclusion: b Stress-only imaging, when possible, substantially reduces radiation dosage and improves patient convenience and experience compared to stress-rest or rest-stress protocols. It is rarely appropriate to repeat imaging if < 2 years after PCI.[8] Imaging post revascularization is a common indication for SPECT MPI, and nuclear labs should encourage high-value imaging guided by a change in clinical status that is concerning for ischemia, assessment of ischemia in the setting of incomplete revascularization or progression of disease. [Extracted from the article]

Background: Cadmium-zinc-telluride (CZT)-based detectors exhibit higher diagnostic sensitivity in myocardial perfusion imaging (MPI) than conventional Anger-MPI for detection of coronary artery disease (CAD); however, reduced specificity and diagnostic accuracy of CZT-MPI were observed. This study aims to compare these different camera systems and to examine the degree of inter-rater reproducibility among readers with varying experience in MPI. Methods: 83 patients who underwent double stress/rest examinations using both a CZT and conventional SPECT cameras within one visit were included. Anonymized and randomized MPI-images were distributed to 15 international readers using a standardized questionnaire. Subsequent coronary angiography findings of ten patients served as a reference for analysis of sensitivity and specificity. Results: Image quality was significantly better in CZT-MPI with significantly lower breast attenuation (P < 0.05). CZT-MPI exhibited higher sensitivity than Anger-MPI (87.5% vs. 62.5%) and significantly reduced specificity (40% vs. 100%). Readers experienced with both camera systems had the highest inter-rater agreement indicating higher reproducibility (CZT 0.54 vs. conv. 0.49, P < 0.05). Conclusions: Higher diagnostic sensitivity of CZT-MPI offers advantages in detection of CAD yet potentially of at the cost of reduced specificity, therefore it requires special training and a differentiated evaluation approach, especially for non-experienced readers with such camera systems. [ABSTRACT FROM AUTHOR]

Background: Phase analysis of gated single photon emission computed tomography (SPECT) myocardial perfusion scintigraphy provides a measure of left ventricular dyssynchrony and may have applications for identifying patients suitable for cardiac resynchronisation therapy. Phase analysis is typically described in degrees of cardiac cycle, less intuitive to cardiologists familiar with ECGs. We assessed the relationship between time and degrees, to determine whether they are interchangeable. Methods and results: 399 patients underwent normal stress-only SPECT myocardial perfusion imaging using Technetium-99m-tetrofosmin. Data analysis used QGS software (Cedars Sinai) calculating bandwidth and standard deviation. Heart rate, age, gender, stress modality, and ejection fraction were analyzed for their relation to phase variables. 13 patients were excluded for conduction abnormalities including right and left bundle branch block and ventricular pacing. Heart rate was strongly correlated to bandwidth and standard deviation measured in time, but unrelated when measured in degrees. Although bandwidth measured by time and degrees were strongly correlated with each other this relationship was not perfect (correlation coefficient 0.87, P <.001). The addition of heart rate to the model explained most of the residual variation between the two. The results for standard deviation were similar. Conclusion: In patients with normal myocardial perfusion and QRS duration bandwidth measured by degrees is not directly interchangeable with time in milliseconds. However most of the variation is explainable by heart rate, which predominantly affects measures of time rather than degrees. We would propose that although the values are less intuitive to cardiologists, normal ranges for phase measured in degrees are potentially more robust. [ABSTRACT FROM AUTHOR]

Coronary artery disease (CAD) is a leading cause of death and morbidity globally. Myocardial perfusion scintigraphy (MPS) is commonly used for the diagnosis of CAD, necessitating hyperaemia achieved either by physical exertion or by pharmacological stress, most commonly through use of a coronary arteriolar dilator. This is challenging in patients with respiratory conditions because exercise may be submaximal and adenosine is contraindicated because of the risk of bronchoconstriction. Regadenoson is the only selective adenosine A2A receptor agonist approved as a vasodilator in MPS. The risk of bronchospasm with regadenoson has been investigated in large, randomised trials; however, patients with the most severe respiratory conditions were not included. In this case series, we present the use of regadenoson MPS in five patients with moderate-to-severe lung conditions, including patients requiring lung volume reduction surgery and lung transplant. In all cases, regadenoson MPS provided valuable information for risk assessment and treatment optimisation. Although dyspnoea occurred in all patients, regadenoson was well tolerated without serious adverse events or bronchospasm; in no case was intervention required to treat dyspnoea. [ABSTRACT FROM AUTHOR]

Over recent years, new evidence has led a rethinking of the available guidance on the diagnosis and management of infective endocarditis (IE). This review compares the most recently available guidance provided by the American Heart Association (AHA) IE Writing Committee, and the Task Force for the management of IE of the European Society of Cardiology (ESC). This represents the sixth of a new series of comparative guidelines review published in the Journal. [ABSTRACT FROM AUTHOR]

In this Guidelines in Review, we review side-by-side the recommendations provided by the 2014 AHA/ACC Guideline for the management of patients with non-ST-elevation acute coronary syndromes and the 2015 ESC Guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation. We review the recommendations for imaging in the evaluation of patients with possible ACS followed by the diagnostic evaluation of patients with proven NSTE-ACS, based on their risk for adverse clinical events. [ABSTRACT FROM AUTHOR]

In 2012, the American College of Cardiology Foundation (ACCF) and the American Heart Association (AHA) Task Force on Practice Guidelines jointly with the American College of Physicians, American Association for Thoracic Surgery, Preventive Cardiovascular Nurses Association, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons produced a set of recommendations intended to assist physicians in the diagnosis and management of patients with stable ischemic heart disease. Two years later, a focused update on the 2012 guidelines was published. A year before this update, The Task Force on the management of stable coronary artery disease (CAD) of the European Society of Cardiology (ESC) issued a guideline on the management of stable CAD. This document brings together European and American recommendations that include the use of stress testing and non-invasive imaging for the diagnosis and management of patients with known or suspected stable CAD. [ABSTRACT FROM AUTHOR]

In 2014, the Task Force on Myocardial Revascularization of the European Society of Cardiology and the European Association for Cardio-Thoracic Surgery with the special contribution of the European Association of Percutaneous Cardiovascular Interventions published a comprehensive set of recommendations on myocardial revascularization in patients presenting with acute or chronic coronary artery disease. In the United States, pertinent guidance on this topic has been published by the American College of Cardiology, American Heart Association and other relevant societies in multiple guideline documents that have been published in recent years. This document brings together European and American recommendations on myocardial revascularization with a focus on the role of cardiac imaging. [ABSTRACT FROM AUTHOR]

Pharmacological stress is an alternative method to dynamic exercise that combined with noninvasive imaging allows the detection of flow-limiting coronary artery disease (CAD). It represents the stress procedure of choice in patients who cannot exercise appropriately. In women, pharmacological stress combined with myocardial perfusion scintigraphy (MPS) has demonstrated to be highly accurate for the detection of obstructive CAD and a valuable tool that helps separate patients at low cardiac risk from those with an adverse prognosis. Pharmacological stress with positron emission tomographic (PET) imaging is increasingly used in the investigation of suspected obstructive CAD; available evidence shows that the diagnostic profile and prognostic value of stress PET imaging is similar to that of stress MPS in women. [ABSTRACT FROM AUTHOR]

Caffeine is a non-selective antagonist at the adenosine receptors, which is expected to reverse both the intended (coronary vasodilation) and unintended (hypotension, flushing) effects of exogenously administered adenosine and adenosine-related compounds. In the past, several studies were conducted to characterize the effect of caffeine on vasodilator myocardial perfusion imaging (MPI) with conflicting results. However, new evidence supports earlier observations and shows that recent caffeine intake attenuates vasodilator-induced myocardial hyperaemia and may therefore reduce the sensitivity of radionuclide MPI for the detection of inducible perfusion abnormality in patients with coronary artery disease. Although the magnitude of this effect and hence its clinical significance are dose dependent, the acute response to equivalent doses of caffeine varies largely among individuals, and this might be explained by differences in caffeine exposure and genetically determined variations in caffeine metabolism. Abstinence from caffeinated foods and beverages for a minimum of 12 hours before vasodilator stress is therefore recommended although longer abstention might be required in order to prevent the potentially blocking effect of residual caffeine on vasodilator-mediated actions. [ABSTRACT FROM AUTHOR]

Non-invasive cardiac imaging plays a major role in modern Cardiology and is becoming an essential step in the assessment of patients with known or suspected coronary artery disease. In this setting, cardiac imaging is combined with stress to assess the functional significance of coronary stenosis. Dynamic exercise is the most physiological form of stress and hence it is regarded as the stress modality of choice. When exercise is not possible, pharmacological stress can be used as an effective and safe alternative. We here describe the mechanism of action, protocols, indications and contraindications as well as the diagnostic performance and safety profile of all pharmacological agents currently available for stress imaging with an emphasis on the newly developed A adenosine receptor agonist, regadenoson. [ABSTRACT FROM AUTHOR]

Purpose: This is the second of a series of surveys designed to assess myocardial perfusion scintigraphy (MPS) practice in Europe. Methods: Data were collected from 258 centres in 18 countries. The number of MPS studies per million population (pmp) was estimated assuming that the nonresponding centres performed either no studies (lower estimate) or the same number as the responding centres (upper estimate). Results: The responding centres served 24% of the population of their countries. The total number of noncardiac nuclear medicine studies was between 2,160 and 8,000 studies pmp. The total number of MPS studies was between 529 and 2,293 pmp. The median number of MPS studies per centre was 571 per year with 57% performing fewer than 500 studies per year and 23% of centres performing fewer than 250 studies per year. There was significant variation between countries, with higher numbers of MPS studies (lower limit of estimate above the mid-range of all countries combined) in Austria, Denmark, Hungary, Portugal and Slovenia, and lower numbers (upper limit of estimate below the mid-range of all countries) in Finland, Norway, Spain and Switzerland. The ratio of MPS to coronary angiography to revascularization procedures was 0.9 to 2.2 to 1. Pharmacological stress was used in 57% and technetium-99m-labelled tracers in 88% of studies. ECG gating was performed in 74% of studies and attenuation correction in 22%. Conclusion: MPS utilization in Europe remains low compared with coronary angiography although there has been a 21% increase in the number of studies pmp in centres that reported in both 2005 and 2007. Pharmacological agents continue to be the predominant form of stress. Despite the widespread use of technetium-99m-labelled tracers, ECG gating is not universally performed. As in the 2005 survey, imaging aids such as attenuation and motion correction and prone imaging are not commonly used. [ABSTRACT FROM AUTHOR]

Background: There are limited data on the effect of body mass index (BMI) on the actions of fixed-dose regadenoson. The purpose of this study was to determine the effect of BMI on the efficacy, side effects, and plasma concentration of regadenoson for Myocardial Perfusion Imaging (MPI). Methods and Results: The study included 2,015 subjects from the ADVANCE MPI trials. Initial adenosine MPI was followed by randomization to regadenoson (400-μg bolus injection) or adenosine (6-minute infusion) MPI. Subjects were classified according to BMI into six categories from underweight (<20 kg/m) to extremely obese (≥40 kg/m). PK modeling was used to predict the effect of BMI on plasma regadenoson concentration (PRC). Adenosine-regadenoson agreement rates for the presence and extent of reversibility were similar across BMI categories ( P > .05). The incidence of side effects was also similar across BMIs ( P ≥ .06). Subjects were less likely to feel very or extremely uncomfortable after regadenoson vs adenosine in all groups with BMI ≥ 25 kg/m, but this trend was not statistically significant in subjects with BMI 20-24 kg/m ( P > .05). PRC was inversely related to BMI with 19% higher PRC in the underweight and 36% lower PRC in the extremely obese compared with a normal weight subject. Conclusions: BMI does not alter the efficacy of regadenoson MPI despite lower PRC in high BMI subjects, or its side effect profile despite higher PRC in low BMI subjects. Regadenoson is better tolerated than adenosine but this benefit seems to lose statistical significance in subjects with BMI < 25 kg/m. [ABSTRACT FROM AUTHOR]

Background: Cardiac computed tomography (CCT) has the potential to assess both coronary anatomy and ventricular function in a single study. We examined the agreement between CCT and myocardial perfusion scintigraphy (MPS) for the assessment of global and regional ventricular function. Methods and Results: Research CCT was performed in 52 patients with a low to intermediate likelihood of coronary artery disease referred for MPS. Left ventricular end-diastolic volume, left ventricular end-systolic volume, left ventricular ejection fraction (LVEF), and myocardial wall motion and thickening were compared between techniques. In addition, myocardial contrast attenuation on CCT was compared with radiotracer uptake on MPS. LVEF values agreed well (mean difference, 4.1%; SD, 15.13%), but CCT left ventricular end-diastolic volume was greater compared with MPS (mean difference, 46.0 mL; SD, 33.34 mL) (P < .001). There was moderate agreement for segmental myocardial motion and thickening, with κ values of 0.57 (95% confidence interval, 0.51-0.63) and 0.47 (95% confidence interval, 0.41-0.53), respectively. Seventeen patients had hypoattenuation in at least 1 myocardial segment on CCT. Three of four patients with concomitant abnormalities of wall motion and thickening on CCT had infarction in the same territory on MPS. Conclusions: There was good agreement for LVEF between CCT and MPS but myocardial volumes differed, and these modalities cannot be used interchangeably. Mild abnormalities of regional function are detected more commonly by CCT than by MPS. Myocardial hypoattenuation on CCT is highly specific for myocardial infarction when associated with reduction of systolic wall thickening and regional wall motion abnormality. [Copyright &y& Elsevier]

Background: Multislice computed tomography coronary angiography (CTA) was proposed as a method for investigating possible coronary artery disease (CAD) in patients who present with chest pain but with a low to intermediate likelihood of CAD. Sixty-four-channel CTA was compared prospectively with 99mTc-tetrofosmin myocardial perfusion scintigraphy (MPS) (as the gold standard in the detection of flow-limiting stenoses) for the detection of functionally significant CAD. Methods and Results: Fifty-two consecutive symptomatic patients with a low to intermediate likelihood of coronary artery disease, and who were referred for MPS, also underwent CTA. The CTA datasets were analyzed by two experienced observers who were blinded to the MPS data, and coronary artery segments were reported as < 50%, 50% to 69%, 70% to 99% stenoses, or occluded. The MPS images were similarly analyzed for inducible perfusion abnormalities, and coronary territories were identified. At the patient level, agreement between CTA and MPS for CTA lesions at ≥ 50% was 87% (sensitivity, 100%; specificity, 84%; positive predictive value, 50%; negative predictive value, 100%). For CTA lesions, agreement at ≥ 70% was 96% (sensitivity, 86%; specificity, 98%; positive predictive value, 86%; negative predictive value, 98%). Conclusions: In patients with a low to intermediate likelihood of CAD, there is good correlation between MPS and CTA for the detection of functionally significant coronary artery stenoses when CTA detects a narrowing of ≥ 70% severity. Computed tomography coronary angiography stenoses of 70% should be used to determine functional significance, and not 50%, as is the usual practice at present. [Copyright &y& Elsevier]

Background: Adenosine may cause bronchoconstriction in subjects with asthma or chronic obstructive pulmonary disease (COPD). Recent evidence suggests that this effect may be dependent on the severity of disease. This study investigates the tolerability of adenosine stress in patients with mild asthma or COPD undergoing myocardial perfusion scintigraphy. Methods and Results: In this case-control study patients with known or suspected mild asthma or COPD were pretreated with an inhaled β2-adrenergic agonist and adenosine titrated up to the maximal dose of 140 μg·kg−1 ·min−1 over a period of 6 minutes. The occurrence of side effects and test tolerability were compared between the airway disease group and 72 control subjects. Of 1261 patients, 124 had known or suspected airway disease; of these, 72 (58%) were suitable for adenosine stress. The proportion of tests completed as per protocol in the asthma/COPD group was similar to that of control subjects (93% vs 100%, P = .06). Dyspnea (n = 38 [53%] in asthma/COPD group vs n = 25 [35%] in control group, P = .03) and chest pain (n = 14 [19%] in asthma/COPD group vs n = 16 [22%] in control group, P = .7) were the most common side effects, and these were mostly mild and well tolerated. Bronchospasm occurred in 5 patients with asthma/COPD but reverted shortly after discontinuation of the adenosine infusion. Aminophylline was not required in any case. Conclusions: A stepwise 6-minute adenosine infusion with prophylactic β2-adrenergic agonist is safe and well tolerated in patients with mild asthma or COPD. [Copyright &y& Elsevier]

Background: Thallium 201, technetium 99m sestamibi (MIBI), and Tc-99m tetrofosmin differ in their myocardial uptake characteristics. This may make the technetium tracers less sensitive for detecting mild to moderate coronary stenosis. Methods and Results: We identified 163 patients with angiographic mild to moderate stenosis (50%-89%) and coexistent severe disease (88/163 patients) from a previous study of patients who received either thallium, MIBI, or tetrofosmin for myocardial perfusion scintigraphy. Summed segmental uptake scores were used to assess myocardial perfusion of territories supplied by the mildly to moderately stenotic vessels. Mean (± SD) summed stress uptake scores in the left anterior descending artery territory were 21.4 ± 3.8, 21.6 ± 4.2, and 22.1 ± 2.3 for thallium, MIBI, and tetrofosmin, respectively (P = .7); mean summed difference uptake scores were 1.2 ± 1.8, 1.1 ± 1.9, and 1.0 ± 1.1, respectively (P = .8). In the non–left anterior descending artery territory, mean summed stress uptake scores were 32.5 ± 6.3, 34.0 ± 6.3, and 34.5 ± 4.7 for thallium, MIBI, and tetrofosmin, respectively (P = .4), whereas mean summed difference scores were 1.9 ± 2.6, 1.7 ± 2.2, and 1.7 ± 2.3, respectively (P = .9). Conclusion: There were no significant differences between the tracers for the summed uptake scores. This suggests that the 3 tracers are comparable in clinical practice for assessing the extent and severity of perfusion abnormalities arising from mild to moderate coronary artery stenosis, especially in the presence of coexistent severe disease. [Copyright &y& Elsevier]

Background: Positron emission tomography (PET) is the non-invasive reference standard for myocardial blood flow (MBF) quantification. Hybrid PET-MR allows simultaneous PET and cardiac magnetic resonance (CMR) acquisition under identical experimental and physiological conditions. This study aimed to determine feasibility of simultaneous 13N-Ammonia PET and dynamic contrast-enhanced CMR MBF quantification in phantoms and healthy volunteers. Methods: Images were acquired using a 3T hybrid PET-MR scanner. Phantom study: MBF was simulated at different physiological perfusion rates and a protocol for simultaneous PET-MR perfusion imaging was developed. Volunteer study: five healthy volunteers underwent adenosine stress. 13N-Ammonia and gadolinium were administered simultaneously. PET list mode data was reconstructed using ordered subset expectation maximisation. CMR MBF was quantified using Fermi function-constrained deconvolution of arterial input function and myocardial signal. PET MBF was obtained using a one-tissue compartment model and image-derived input function. Results: Phantom study: PET and CMR MBF measurements demonstrated high repeatability with intraclass coefficients 0.98 and 0.99, respectively. There was high correlation between PET and CMR MBF (r = 0.98, p < 0.001) and good agreement (bias − 0.85 mL/g/min; 95% limits of agreement 0.29 to − 1.98). Volunteer study: Mean global stress MBF for CMR and PET were 2.58 ± 0.11 and 2.60 ± 0.47 mL/g/min respectively. On a per territory basis, there was moderate correlation (r = 0.63, p = 0.03) and agreement (bias − 0.34 mL/g/min; 95% limits of agreement 0.49 to − 1.18). Conclusion: Simultaneous MBF quantification using hybrid PET-MR imaging is feasible with high test repeatability and good to moderate agreement between PET and CMR. Future studies in coronary artery disease patients may allow cross-validation of techniques. [ABSTRACT FROM AUTHOR]