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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.

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.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).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.

The purpose of this study was to evaluate the feasibility and accuracy of combined coronary and perfusion cardiovascular magnetic resonance (CMR) in the assessment of coronary artery stenosis. Thirty-five consecutive patients (27 men, eight women, age range 34-81 years), undergoing cardiac catheterization, were assessed with 3D coronary CMR and rest-stress perfusion CMR. Significant coronary stenosis was determined by vessel narrowing or signal loss with coronary CMR, and by abnormal contrast enhancement with perfusion CMR. Coronary artery diameter stenosis greater than 50% was considered significant with conventional cardiac catheterization. Seventeen patients had significant coronary artery disease, and in these there were 35 significant stenoses on cardiac catheterization. All left main stem arteries were normal on both cardiac catheterization and coronary CMR. For the diagnosis of coronary artery stenosis, coronary CMR had a sensitivity of 92% for the left anterior descending artery (LAD), 79% for the right coronary artery (RCA), but only 13% for the circumflex coronary artery (LCX). Perfusion CMR had corresponding sensitivities of 69%, 86%, and 63%, respectively. For all arteries the accuracies for coronary and perfusion CMR were 67% and 72%, respectively. Combining coronary and perfusion CMR improved the accuracy to 77%. These data demonstrate that in patients with suspected coronary artery disease, combined coronary and perfusion CMR is feasible, increases the accuracy of detection of significant coronary stenosis, and offers the possibility of combined anatomical and hemodynamic assessment of coronary artery stenosis.

Background— The extent and severity of ischemia on myocardial perfusion scintigraphy (MPS) is commonly used to risk-stratify patients with coronary artery disease. Estimation of ischemic burden by cardiovascular magnetic resonance (CMR) with conventional 2-dimensional myocardial perfusion methods is limited by incomplete cardiac coverage. More recently developed 3-dimensional (3D) myocardial perfusion CMR, however, provides whole-heart coverage. The aim of this study was to compare ischemic burden on 3D myocardial perfusion CMR with 99m Tc-tetrofosmin MPS. Methods and Results— Forty-five patients who had undergone clinically indicated MPS underwent rest and adenosine stress 3D myocardial perfusion and late gadolinium enhancement CMR. Summed stress and rest scores were calculated for MPS and CMR using a 17-segment model and expressed as a percentage of the maximal possible score. Ischemic burden was defined as the difference between stress and rest scores. 3D myocardial perfusion CMR and MPS agreed in 38 of the 45 patients for the detection of any inducible ischemia. The mean ischemic burden for MPS and CMR was similar (7.5±8.9% versus 6.8±9.5%, respectively, P =0.82) with a strong correlation between techniques (rs=0.70, P P =0.45). Conclusions— 3D myocardial perfusion CMR is an alternative to MPS for detecting the presence and rating the severity of ischemia.

It is well known that gingivitis is a bacterially-elicited inflammation of the marginal gingiva. A number of chemical agents have been evaluated over the years with regard to their antimicrobial effects in the oral cavity; however, all are associated with side effects that prohibit regular long-term use. Therefore, the effectiveness of a natural Mexican Sanguinaria extract (Polygonum aviculare L.) against gingivitis, was assessed in 60 male dentistry students between the ages of 18 and 25 years. Over a period of 2 weeks, these students used the Sanguinaria extract (1 mg/ml) in oral rinse twice daily as a unique oral health measurement (no tooth-brushing was allowed). The O'Leary Plaque Index and the Loe and Silness Gingivitis Index were recorded at baseline (day 0) in all the subjects. Also, a complete prophylaxis was performed after both indices were obtained. The antibacterial and antiinflammatory effects of the extract were evaluated on days 7, 11 and 14. The results showed that the Mexican Sanguinaria extract in oral rinse significantly decreased gingivitis from day 0 (-x=1. 056) to day 14 (-x=1.011) (P

Stress myocardial perfusion scintigraphy (MPS) plays a major role in the detection of obstructive coronary artery disease and provides valuable diagnostic and prognostic information to guide clinical decision-making with regard to medical therapy and coronary revascularisation. Current stress techniques for MPS are effective but their use may be limited by reduced tolerability, contraindications and untoward side effects. The recently developed selective adenosine A2A receptor agonists have the potential for improving stress tolerability, hence expanding the indications for functional imaging in the assessment of coronary artery disease.This article reviews the basic principles underlying activation of coronary arteriolar adenosine A2A receptors. It describes the benefits and limitations of current vasodilator stress agents and highlights the effectiveness, side effect profile and tolerability of regadenoson, the only selective adenosine A2A receptor agonist available at present for clinical use.The reader will gain an understanding of the pharmacokinetics and mechanism of action of regadenoson for the assessment of coronary artery disease when combined with myocardial perfusion imaging. The reader will also become aware of the available evidence on the clinical usefulness of regadenoson MPS and its future applications.Selective activation of coronary arteriolar adenosine A2A receptors by regadenoson provides an effective modality of stress for the detection of inducible perfusion abnormality in patients with known or suspected coronary disease. The effectiveness of regadenoson is similar to that of adenosine, but test tolerability is improved with regadenoson. The use of this agent simplifies stress testing and has the potential for expanding the applications of functional imaging to patient populations unsuitable for conventional vasodilator stress with adenosine or dipyridamole.

Cardiovascular events account for half of the deaths related to non-cardiac surgery. Identification of a patient's risk and perioperative management appropriate to that risk is important to optimize the clinical outcome of surgery. Key concepts of preoperative cardiac risk assessment are contained within American and European guidelines. Risk indices stratify patients according to clinical and surgery-specific predictors. The most widely used is the Lee index; however, all have limitations. Patients at intermediate and high risk following risk index stratification and assessment of functional capacity require further non-invasive assessment to detect myocardial ischaemia using, for instance, exercise electrocardiography, myocardial perfusion scintigraphy, or stress echocardiography. It can be difficult, however, to decide which technique and predictor is most effective and local practice differs. Invasive coronary angiography is not recommended unless it would be performed in the absence of surgery. Appropriate pain management should be considered in all patients and beta-blockade may improve the outcome in intermediate- and high-risk patients. Identifying patients with risk factors or previously undiagnosed coronary artery disease enables the preoperative cardiac risk assessment to guide long-term treatment.

Cardiac stress testing, whether alone or combined with cardiac imaging, plays a major role in the diagnosis of coronary artery disease by provoking myocardial ischaemia and allowing the detection of myocardial perfusion abnormalities that arise from flow-limiting coronary stenosis. Cardiac stress imaging provides valuable diagnostic and prognostic information that guides clinical decision-making with regard to medical therapy and revascularisation. Dynamic exercise and pharmacological stress agents are used for this purpose with newly developed agents able to overcome some of the limitations of existing methods. Evidence shows that all current forms of stress are safe and have a similar diagnostic performance. With some exceptions, the selection of one form of stress over the others would mainly be dictated by patient characteristics and preferences, imaging technique and protocols, and local expertise and availability. Cardiac stress is an essential part of diagnostic imaging, and current practice relies on a number of methods that are equally effective for the detection of obstructive coronary artery disease.

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 usedin 57% and technetium99m-labelled tracers in 88% of studies. ECG gating was performed in 74% of studies and attenuation correction in 22%. Conclusion MPSutilizationinEuroperemainslowcompared with coronary angiography although there has been a 21% increase in the number of studies pmp in centres that reported inboth2005and2007.Pharmacological agentscontinuetobe 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.

Mortality rates due to coronary arterial disease (CAD) have declined as result of improved prevention, diagnosis and management, but CAD remains the leading cause of death. Myocardial perfusion scintigraphy (MPS) provides a cost-effective tool for early detection of CAD in symptomatic individuals and can stratify patients according to risk of cardiac events. MPS also provides valuable information to assist clinical decision-making. A large body of evidence supports the current applications of MPS, which has become integral to several guidelines for clinical practice.

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

Obesity is a chronic disease with an increasing prevalence in all groups of age, and is associated to increased general mortality and cardiovascular risk. The multidisciplinary non surgical approach must be the treatment of choice for obese subjects. However, the results of such approach among subjects with severe or morbid obesity, are unsatisfactory. In this group of patients, bariatric surgery and specifically gastric bypass achieves good long term results, maintaining a low body mass index, reducing complications and improving quality of life. Considering the widespread practice of bariatric surgery in Chile, the Nutrition Unit of the Ministry of Health formed a task force to propose update guidelines for the surgical treatment of obesity. These guidelines were proposed after a thorough literature review and discussion with groups that practice bariatric surgery using defined protocols. This document provides a summarized version of the guidelines. The first section discusses the background for bariatric surgery and the second part give specific recommendations for patient management and the formation of reference centers for surgical management of obesity.

Obesity is a chronic disease with an increasing prevalence in all groups of age, and is associated to increased general mortality and cardiovascular risk. The multidisciplinary non surgical approach must be the treatment of choice for obese subjects. However, the results of such approach among subjects with severe or morbid obesity, are unsatisfactory. In this group of patients, bariatric surgery and specifically gastric bypass achieves good long term results, maintaining a low body mass index, reducing complications and improving quality of life. Considering the widespread practice of bariatric surgery in Chile, the Nutrition Unit of the Ministry of Health formed a task force to propose update guidelines for the surgical treatment of obesity. These guidelines were proposed after a thorough literature review and discussion with groups that practice bariatric surgery using defined protocols. This document provides a summarized version of the guidelines. The first section discusses the background for bariatric surgery and the second part give specific recommendations for patient management and the formation of reference centers for surgical management of obesity.

The aim of this study was to determinate the performance of body mass index (BMI) for the diagnosis of obesity and as a predictor of body fatness in adult Chilean subjects. We conducted a study in 433 women (18-73 years old; BMI: 19.7 to 69.7 kg/m2) and 264 men (18-83 y.; BMI: 19.1 to 54.8 kg/m2). Bioelectrical resistance was measured by impedance method and fat mass percent (FM%) was calculated by fatness-specific equations developed by Segal et al. Obesity was defined as a BMI of at least 30 kg/m2. Increased fatness was defined by the FM% cut-off points of at least 25% for men and at least 30% for women. Sixty-four percent of women and 23.6% of men with BMI below 30 kg/m2 had FM% higher than 30% and 25%, respectively. A value of BMI of 26 kg/m2 in women and 30 kg/m2 in men had the best agreement to the cut-off points of fatness according to sensitivity vs. specificity analysis The following equations were developed to predict individual fatness: women FM% = 0.96 x BMI + 0.154 x age + 1.44 (r2 = 0.75; standard error 3.8%); men FM% = 0.99 x BMI + 0.141 x age - 9.914 (r2 = 0.66; standard error 4.4%). Differences between measured and predicted FM% presented a wide variation, with a range of +/- 2 sd of 7.5% in women and 8.8% in men. The commonly used value of BMI 330 kg/m2 as a cut-off point for obesity does not have adequate sensitivity and specificity for the screening of increased fatness subjects, specially in women. In this study BMI shows a low reliability as a predictor of individual body fatness, particularly in men and in subjects with a BMI below 30 kg/m2.

Radionuclide myocardial perfusion imaging uses an intravenous radiopharmaceutical to image myocardial perfusion during stimulation of the perfusion system and at rest. The images are acquired using a gamma camera. Tomographic imaging is preferred over planar imaging because of the three dimensional nature of the images and their superior contrast resolution. Comparison of the myocardial distribution of the radiopharmaceutical after stress and at rest provides information on myocardial viability, inducible perfusion abnormalities, and, when ECG gated imaging is used, global and regional myocardial function. Radionuclide myocardial perfusion imaging is an established and non-invasive imaging technique with diagnostic and prognostic efficacy in the investigation of coronary artery disease. It is the only widely available test for assessing myocardial perfusion directly, but there are variations in the way it is performed in different centres. Harmonisation of practice, at least at a national level, is therefore essential, and clinical governance now makes it mandatory for practice to be based upon evidence whenever possible.1 This is best achieved by expert analysis of the evidence, and to this end the British Nuclear Cardiology Society (BNCS), in association with the British Cardiac Society (BCS) and the British Nuclear Medicine Society (BNMS), have developed procedure guidelines for tomographic myocardial perfusion imaging. The guidelines are intended to assist medical practitioners and other healthcare professionals in recommending, performing, interpreting, and reporting single photon emission computed tomography (SPECT) of myocardial perfusion. They do not cover the benefits or drawbacks of the technique in specific circumstances; neither do they address its cost–effectiveness in clinical diagnosis and management or its potential impact on clinical outcomes. The writing group was composed of clinicians and scientists from different specialties but all with subspecialty expertise in nuclear cardiology. The advisory group consisted of nominated representatives of the BNCS, the BNMS, and the guidelines committee of …

To evaluate a simplified protocol by using free-breathing three-dimensional (3D) coronary magnetic resonance (MR) angiography to determine the anatomy of anomalous coronary arteries, in particular the relationship of the vessels to the aortic root.Twenty-six patients (18 men, eight women; mean age, 50 years; age range, 18-77 years) who had a history of chest pain, palpitations, or syncope and who were suspected of having coronary artery anomalies were examined with free-breathing MR angiography. Multiple 3D volume slabs were acquired at the level of the sinuses of Valsalva by using diaphragmatic navigators for respiratory artifact suppression. The proximal anatomy of the coronary arteries was determined.Six anomalous circumflex arteries originated from the right sinus of Valsalva and passed behind the aortic root. Six right coronary arteries arose from the left sinus of Valsalva and coursed between the aortic root and the right ventricular outflow tract (RVOT). Nine left coronary arteries arose from the right sinus of Valsalva; seven of nine coursed between the aortic root and the RVOT. Five patients had minor anomalies. Overall, in eight patients with anomalous arteries that coursed between the aortic root and the RVOT, conventional coronary angiography could not be used confidently to identify the proximal course.Free-breathing 3D coronary MR angiography can be used to identify the proximal anatomy of anomalous coronary arteries.

The commonly used predictive equations to calculate resting energy expenditure (REE) can yield inaccurate results.To compare measured REE, with estimated REE in normal and obese adults. To develop specific predictive equations for our population.Eight hundred sixteen women aged 18 to 74 years old with a body mass index (BMI) between 18.5 and 69.7 kg/m2 and 441 men aged 18 to 71 years old with a BMI between 185 and 67.9 kg/m2 were studied. REE was measured by indirect calorimetry and fat free mass by tetrapolar bioimpedance. REE was also estimated using FAO/WHO (F/W) and Harris-Benedict (H/B) equations.Measured REE in controls was 20.7 +/- 1.9 and 23.6 +/- 3.3 kcal/kg/day in women and men respectively. The figures for overweight women and men were 19.8 +/- 1.9 and 20.0 +/- 2 kcal/kg/day, for obese women and men were 18.3 +/- 1.7 and 19.0 +/- 1.8 kcal/kg/day and for morbidly obese women and men, were 16.9 +/- 1.8 and 16.1 +/- 1.7 kcal/kg/day. When REE was corrected for fat free mass, no differences between controls and different degrees of obesity, were observed. The difference between estimated and measured REE ranged from -420 to 617 kcal in women and from -400 to 900 kcal in men. The equations derived using data obtained in the present study, showed a better predictive accuracy.An important error was detected when REE was predicted using FAO/WHO or Harris Benedict equations, in Chilean obese subjects. Therefore these equations must be used with caution, local equations must be devised or resting energy expenditure must be measured by indirect calorimetry.

The commonly used predictive equations to calculate resting energy expenditure (REE) can yield inaccurate results. Aim: To compare measured REE, with estimated REE in normal and obese adults. To develop specific predictive equations for our population. Patients and Methods: Eight hundred sixteen women aged 18 to 74 years old with a body mass index (BMI) between 18.5 and 69.7 kg/m² and 441 men aged 18 to 71 years old with a BMI between 185 and 67.9 kg/m2 were studied. REE was measured by indirect calorimetry and fat free mass by tetrapolar bioimpedance. REE was also estimated using FAO/WHO (F/W) and Harris-Benedict (H/B) equations. Results: Measured REE in controls was 20.7 ± 1.9 and 23.6 ± 3.3 kcal/kg/day in women and men respectively. The figures for overweight women and men were 19.8 ± 1.9 and 20.0 ± 2 kcal/kg/day, for obese women and men were 18.3 ± 1.7 and 19.0 ± 1.8 kcal/kg/day and for morbidly obese women and men, were 16.9 ± 1.8 and 16.1 ± 1.7 kcal/kg/day. When REE was corrected for fat free mass, no differences between controls and different degrees of obesity, were observed. The difference between estimated and measured REE ranged from -420 to 617 kcal in women and from -400 to 900 kcal in men. The equations derived using data obtained in the present study, showed a better predictive accuracy. Conclusions: An important error was detected when REE was predicted using FAO/WHO or Harris Benedict equations, in Chilean obese subjects. Therefore these equations must be used with caution, local equations must be devised or resting energy expenditure must be measured by indirect calorimetry (Rev Méd Chile 2002; 130: 51-60)

This editorial refers to ‘Potential impact of myocardial perfusion scintigraphy as gatekeeper for invasive examination and treatment in patients with stable angina pectoris: observational study without post-test referral bias’† by P.F. Hoilund-Carlsen et al ., on page 29 Myocardial perfusion scintigraphy (MPS) is an effective and cost-effective technique in patients presenting with stable chest pain. It provides a reliable assessment of coronary obstruction leading to inducible perfusion abnormalities and of the prognosis of disease. It can therefore be used both for diagnosis and for triage of patients between initial medical therapy and invasive investigation with a view to revascularization. It is recommended as the first-line diagnostic procedure when exercise electrocardiography is difficult or inconclusive, such as when the resting ECG is abnormal, when maximal dynamic exercise is unlikely to be achieved, and in women.1 Although comparison between a test of coronary function and coronary anatomy is fraught with difficulties, the sensitivity of MPS for detecting angiographic stenosis is 85–90% and the normal MPS rate in a low likelihood population (normalcy) is 90–95%, depending upon the population studied.2 As with any diagnostic test, MPS is most useful in patients with an intermediate (25–75%) likelihood of underlying coronary disease, but its prognostic value also makes it helpful in patients with a high likelihood. It is diagnostically least useful in patients with a low likelihood of disease in whom performing any diagnostic test can be questioned, although a normal scan reliably indicates a risk of myocardial infarction or cardiac death below 1% per year for up to 5 or even 10 years depending upon risk factors. Coronary angiography has historically been used as the gold standard for the diagnosis of coronary disease although as an anatomical test it does not … *Corresponding author. E-mail address : r.underwood{at}imperial.ac.uk

A 68-year-old gentleman with prior uncomplicated coronary bypass grafting (CABG) presented with worsening symptoms of angina and was accordingly referred for urgent coronary computed tomography angiography (CTA). Coronary CTA showed a dilated left mainstem (LMS) artery measuring 9 mm at the ostium that filled a large aneurysm (51 mm × 52 mm × 49 mm) ( Figure 1A ). The wall of the aneurysm was partly calcified and contained thrombus ( Figure 1B ). The contrast-filled lumen measured 25 mm, with the neck of the aneurysm measuring

Background: Attenuation correction with simultaneous transmission/ emission imaging improves the detection of coronary artery disease by myocardial perfusion single-photon emission computed tomography (SPECT), but there are few published data on its role in the detection of viable myocardium. Methods: Subjects with chronic ischaemic left ventricular dysfunction underwent nitrate-enhanced resting 99mTc-tetrofosmin SPECT with simultaneous transmission imaging using two roving 153Gd line sources on a dual-head gamma camera, as well as 18F-2-fluorodeoxyglucose positron emission tomography (FDG-PET). The three sets of tomograms attenuation-corrected SPECT (AC-SPECT), non-corrected SPECT (NAC-SPECT) and FDG-PET were assessed semi-quantitatively using a segmental model, and blinded to clinical and other imaging information. Results: 11 subjects (10 males; age 68±10 years; LVEF 26.9±6.2%) were recruited. The percentages of studies rated as good quality were the same for AC-SPECT and NAC-SPECT (73% for both). The weighted kappas for segmental tracer uptake agreement between AC-SPECT and FDG-PET, and between NAC-SPECT and FDG-PET, were comparable (0.62 versus 0.63). The concordance rate for viability between AC-SPECT and FDG-PET was 81%, while that between NAC-SPECT and FDG-PET was 82% (difference 1%; p=0.71). Bland-Altman analysis revealed a mean difference between AC-SPECT and FDG-PET segmental percentage tracer uptake of +2.21%, with a standard deviation of 17.1%. This did not differ significantly from the mean difference between NAC-SPECT and FDG-PET of −0.4±18.3%. Conclusion: In this pilot study, using FDG-PET as a gold standard, AC-SPECT did not improve the detection of viable myocardium when compared with NAC-SPECT.

Background: Vasodilator stress is traditionally contraindicated in patients with asthma or chronic obstructive airways disease (A/COAD). However, recent evidence suggests that adenosine is safe in well-controlled disease. We conducted a systematic review of the safety and tolerability of adenosine stress in patients with A/COAD. Methods: 124 patients (46% asthma, 54% COAD) were identified from 1261 consecutive subjects referred for myocardial perfusion SPECT imaging. Patients were given adenosine if asthma only mild or moderate, no admission for an exacerbation in last year, no current steroid therapy, documented FEV1 or peak expiratory flow ≥70% predicted, no wheeze on auscultation. An inhaled short-acting beta-2-agonist (salbutamol, 200 mcg) was administered and adenosine titrated starting at 70 mcg/kg/min for 1 minute, increasing to 100 mcg/kg/min for another 1 minute up to the maximal dose of 140 mcg/kg/min for 4 minutes. Radiotracer was injected 2 minutes before termination of the adenosine infusion. Adherence to protocol, patient symptoms and complications were compared with a control group (non-A/COAD) matched for age, sex and clinical indications. Results: Of 124 patients, 72 (58%) were suitable for adenosine stress. Adenosine was combined with exercise in the majority of cases (86.1%). The protocol was completed successfully in a similar proportion of tests (100% control vs. 97.2% A/COAD, p=0.5). Symptoms were mostly minor and well tolerated, with dyspnoea reported more often in the A/COAD group (50% vs. 34% p=0.03). There were 4 cases of bronchospasm in the A/COAD group, all reverted shortly after discontinuation of adenosine (n=2) or administration of inhaled salbutamol. Aminophylline was not required. No other complications were reported. A similar proportion of studies showed reversible perfusion abnormalities in both groups (42% A/COAD vs. 50% control, p=0.3). Conclusion: A titrated adenosine protocol with prophylactic use of an inhaled beta-2-agonist is a safe procedure in patients with history of mild, well-controlled asthma or COAD undergoing stress myocardial perfusion imaging.

Background Hypertriglyceridemia in combination with low HDL cholesterol levels is a risk factor for cardiovascular disease. Our objective was to evaluate the efficacy of ciprofibrate for the treatment of this form of dyslipidemia and to identify factors associated with better treatment response.

An asymptomatic 21 year old man with non-obstructive hypertrophic cardiomyopathy (HCM) was referred for radionuclide myocardial perfusion imaging for risk assessment. Adenosine was infused at 140 μg/kg/min over six minutes with submaximal bicycle exercise and thallium-201 (80 MBq) was injected intravenously at three minutes. Stress images were acquired five minutes after …

Objectives:We studied whether an increase in adenosine dose overcomes caffeine antagonism on adenosine-mediated coronary vasodilation.Background:Caffeine is a competitive antagonist at the adenosine receptors, but it is unclear whether caffeine in coffee alters the actions of exogenous adenosine, and whether the antagonism can be surmounted by increasing the adenosine dose.Methods:Myocardial perfusion scintigraphy (MPS) was used to assess adenosine-induced hyperemia in 30 patients before (baseline) and after coffee ingestion (caffeine). At baseline, patients received 140 µg/kg/min of adenosine combined with low-level exercise. For the caffeine study, 12 patients received 140 µg/kg/min of adenosine (standard) and 18 patients received 210 µg/kg/min (high dose) after caffeine intake (200 mg). Myocardial perfusion was assessed semiquantitatively and quantitatively, and perfusion defect was characterized according to the presence of reversibility.Results:Caffeine reduced the magnitude of perfusion abnormality induced by standard adenosine as measured by the summed difference score (SDS) (12.0 ± 4.4 at baseline vs. 4.1 ± 2.1 after caffeine, p < 0.001) as well as defect size (18% [3% to 38%] vs. 8% [0% to 22%], p < 0.01), whereas it had no effect on the abnormalities caused by high-dose adenosine (SDS, 7.7 ± 4.0 at baseline vs. 7.8 ± 4.2 after caffeine, p = 0.7). There was good agreement between baseline and caffeine studies for segmental defect category (kappa = 0.72, 95% confidence interval: 0.65 to 0.79) in the high-dose group. An increase in adenosine after caffeine intake was well tolerated.Conclusions:Caffeine in coffee attenuates adenosine-induced coronary hyperemia and, consequently, the detection of perfusion abnormality by adenosine MPS. This can be overcome by increasing the adenosine dose without compromising test tolerability.

Purpose Regadenoson was approved for clinical use in Europe in 2011. Since then, it has become the default form of stress at our institution. We have assessed the side-effect profile and tolerability of regadenoson in patients undergoing clinically indicated myocardial perfusion scintigraphy between July 2011 and July 2012. Methods Clinical, stress and imaging data were recorded prospectively. Symptoms during stress were recorded and defined as mild, moderate or severe. An adverse event was defined as any symptom that persisted for more than 30 min or that required investigation or treatment. Results Of 1,764 consecutive patients, 1,581 (90 %) received regadenoson combined with submaximal exercise unless contraindicated. Symptoms were common (63 %) but transient and well-tolerated. The severity of symptoms was recorded in most patients as mild (84 %). Dyspnoea (36 %) and chest discomfort (12 %) were the commonest side effects. Adverse events were reported in eight patients (0.5 %), thought to be vasovagal in seven of these. All patients recovered fully without sequelae. There were no deaths, myocardial infarction or hospital admissions. Regadenoson stress was performed in 206 patients (12 %) with asthma or chronic obstructive pulmonary disease (COPD) without bronchospasm or any other major side effect. Conclusion We studied the symptom profile of regadenoson in the largest European cohort to date. Regadenoson combined with submaximal exercise was well tolerated, notably also in patients with asthma or COPD. The majority of regadenoson-related adverse events were vasovagal episodes without sequelae.

Background CMR perfusion (CMRP) imaging using adenosine traditionally requires bilateral arm cannulation. Patients with multiple comorbidities often have difficult venous access and dual cannulation often proves impossible. We used a standard two-way adapter (Octopus Vygon with no-reflow valve) to administer adenosine at a standard rate of 140 mcg/kg/minute over 3 minutes for maximum coronary vasodilatation following a bolus injection of gadolinium. High flow bolus injection may cause sinus arrest caused by a flush of residual adenosine in the same arm vein. We acquired 50 sequential R-wave triggered image frames to assess first pass myocardial perfusion and assessed the effect of significant sinus pauses on image acquisition.

ss Open Acce Poster presentation Diagnostic performance of perfusion cardiovascular magnetic resonance compared with gated myocardial perfusion spect in patients with known or suspected coronary artery disease Jonathan Lyne*1, Chiara Bucciarelli-Ducci1, Eliana Reyes2, Ravi Assomull1, Joanna Petryka1, Stuart Watkins1, Peter Gatehouse1, Micheal Roughton1, Karen Symmonds1, Sanjay Prasad1, Richard Underwood3 and Dudley Pennell1