Radionuclide Perfusion Imaging Research Articles

Cardiac positron emission tomography and other modalities for coronary artery disease assessment: A snapshot from the medicare data

BackgroundPositron emission tomography (PET) is an important tool for assessing coronary artery disease (CAD), but its widespread utilization is limited due to various factors, including limited local champion availability. This study aims to compare the frequency of PET procedures and their interpreters with other common CAD assessment modalities. MethodsUsing Medicare data, we examined the number of cardiac PET procedures billed and compared them with single-photon emission computed tomography (SPECT), coronary computed tomography angiography (CCTA), stress magnetic resonance imaging (MRI), and stress echocardiography. Healthcare Common Procedure Coding System codes were used to identify procedures. We calculated the total number of PET myocardial perfusion imaging (MPI) procedures, the proportion of PET/CT and myocardial blood flow (MBF) assessments, and the median number of studies read per physician. We also analyzed the trends in the use of different CAD assessment modalities between 2018 and 2022. Descriptive statistics summarized the data. ResultsIn 2022, Medicare billed for 212,106 PET MPI scans. SPECT was six times more frequent (1,343,519), whereas stress echocardiography (201,676) and CCTA (118,734) had similar or lower use. Stress MRI (3,932) was least used. Of the PET MPI scans, 46% were PET/CT, and 39% included MBF measurements. Cardiologists interpreted 86% of PET scans, with a median of 58 studies per reader; 23% interpreted ≤25 studies annually. SPECT had a median of 63 studies per reader, and CCTA, stress MRI, and stress echocardiography had medians of 27, 20, and 24, respectively. PET, CT, and MRI use increased from 2018 to 2022, whereas SPECT and stress echocardiography declined. ConclusionIn the Medicare population, radionuclide perfusion imaging (SPECT and PET) remained the preferred method for assessment of CAD, with SPECT being the most frequently used modality and PET being the second most frequently used modality for this application. However, PET/CT and MBF are underutilized, limiting diagnostic and prognostic capabilities. Efforts to enhance education and awareness of PET's advantages and to address barriers to its wider adoption are essential to maximize its clinical benefits and improve patient outcomes.

Evaluation of Brain Perfusion with Radionuclide Imaging in Dementia Patients

Objective: This study aims to evaluate the perfusion in the affected brain lobes with radionuclide imaging in patients with dementia and to contribute to the literature by determining the relationship between the degree of dementia. Methods: In this retrospective study, 44 adult patients were included. The mean age of the patients was 73 (57-87). Twenty-three (52.3%) of these were female. All patients underwent mini-mental state test, neurological examinations and radionuclide brain perfusion imaging. The areas of interest of the frontal, parietal, temporal, and occipital lobes and the cerebellum were drawn, respectively, and the cerebellum ratios of the relevant lobes were compared. In this way, brain perfusion index values of lobes were obtained. Results: Brain perfusion in group 1 was higher than in other groups. Groups were also compared in pairs. There was no significant difference in perfusion values in the occipital lobe. There was a significant difference in perfusion between groups 1 and 2 in lobes other than the occipital lobe. This was also the case for Groups 1 and 3. When group 2 with early dementia symptoms, and group 3 with moderate dementia were compared, there was a significant difference between the perfusion values of only the right and left frontal lobes. Conclusion: Early diagnosis is very important in progressive dementia. Clinical tests are successfully applied to categorize patients. Evaluation of brain perfusion and metabolism with functional radionuclide imaging is significant in guiding the treatment and evaluating the success of the treatment.

Application of radionuclide myocardial perfusion imaging in patients with chronic kidney disease

Cardiovascular disease is the leading cause of death in patients with chronic kidney disease (CKD) or even those after renal transplantation. Radionuclide myocardial perfusion imaging (MPI) is an available way to predict cardiac events and make risk stratification for CKD patients with cardiovascular diseases. Early detection and individualized treatment of patients with high-risk of cardiac events by MPI can prevent myocardial infarction and heart failure, thus improving the survival rate of this population. This article reviews the application of MPI in patients with CKD. Key words: Nephrosis; Chronic disease; Myocardial perfusion imaging; Trends

The Clinical use of Stress Echocardiography in Ischemic Heart Disease Cardiovascular Ultrasound (2017)15:7. Translation authors: Arystan A.Zh., Fettser D.V.

Stress echocardiography is an established technique for the assessment of extent and severity of coronary artery disease. The combinationof echocardiography with a physical, pharmacological or electrical stress allows detecting myocardial ischemia with an excellentaccuracy. A transient worsening of regional function during stress is the hallmark of inducible ischemia. Stress echocardiographyprovides similar diagnostic and prognostic accuracy as radionuclide stress perfusion imaging or magnetic resonance, butat a substantially lower cost, without environmental impact, and with no biohazards for the patient and the physician. The evidenceon its clinical impact has been collected over 35 years, based on solid experimental, pathophysiological, technological and clinicalfoundations. There is the need to implement the combination of wall motion and coronary flow reserve, assessed in the left anteriordescending artery, into a single test. The improvement of technology and in imaging quality will make this approach more andmore feasible. The future issues in stress echo will be the possibility of obtaining quantitative information translating the currentqualitative assessment of regional wall motion into a number. The next challenge for stress echocardiography is to overcome itsmain weaknesses: dependence on operator expertise, the lack of outcome data (a widespread problem in clinical imaging) to documentthe improvement of patient outcomes. This paper summarizes the main indications for the clinical applications of stressechocardiography to ischemic heart disease.

Stress Echocardiography: An Update

Stress echocardiography (SE) is an established technique for the assessment of extent and severity of coronary artery disease. The combination of echocardiography with a physical, pharmacological or electrical stress allows to detect myocardial ischemia with an excellent accuracy. A transient worsening of regional function during stress is the hallmark of inducible ischemia. In recent years, SE has become an established method for the assessment of a wide spectrum of challenging clinical conditions, including systolic or diastolic heart failure, non-ischaemic cardiomyopathy, valvular heart disease, pulmonary hypertension (PH), athletes’ hearts, congenital heart disease (CHD) and heart transplantation. Advantages of SE include the ubiquitous availability of echocardiography, lack of ionising radiation, choice of physiological or pharmacological stressors, good diagnostic accuracy and robust supporting evidence base. SE has evolved significantly as a technique over the past three decades and has benefitted considerably from improvements in overall image quality (superior resolution), machine technology (e.g. digital cine-loop acquisition and side-by-side image display) and development of second-generation ultrasound contrast agents that have improved reader confidence and diagnostic accuracy. SE provides similar diagnostic and prognostic accuracy as radionuclide stress perfusion imaging or magnetic resonance, but at a substantially lower cost, without environmental impact, and with no biohazards for the patient and the physician. A paradigm shift will occur when from a highly expertise qualitative reading SE will move to a quantitative approach that would make it easier also for less skilled readers. Technological premises are there at hand but they have not reached a full-blown status to be used on a routine clinical basis. Society recommendations and guidelines are mostly based on consensus and level of evidence C. The gap of knowledge should be filled with prospective large scale studies to support evidence-based treatment strategies. The purpose of this article is to review the breadth of SE in contemporary clinical cardiology.University Heart Journal Vol. 14, No. 1, Jan 2018; 31-37

Features of radionuclide myocardial perfusion imaging in patients with homozygous familial hypercholesterolemia

Objective To evaluate the features of myocardial perfusion imaging (MPI) in patients with homozygous familial hypercholesterolemia (HoFH) and its influence factors. Methods Forty-two consecutive HoFH patients (21 males, 21 females; average age: (14.8±8.4) years) were retrospectively enrolled in this study from June 2010 to November 2016. Diagnosis was proved by clinical and chromosome tests, and all patients underwent ATP stress and rest 99Tcm-methoxyisobutylisonitrile (MIBI) SPECT MPI with a two-day protocol. Summed stress score (SSS) and summed rest score (SRS) were acquired, and summed difference score (SDS; SSS-SRS) was calculated. Relations between SSS, SRS, SDS and age, lipid profile were analyzed. Two-sample t test, χ2 test, multiple linear regression analysis and multivariate logistic regression were used to analyze the data. Results There were 24 patients with positive MPI results (SSS≥1), and females (76.2%, 16/21) showed more positive MPI results than males (38.1%, 8/21; χ2=6.22, P 0.05). Positive electrocardiograph (ECG) in ATP stress test was observed in 9 females (42.9%, 9/21) and 3 males (14.3%, 3/21; χ2=4.20, P<0.05). Sixty-three (8.8%, 63/714) abnormal myocardial perfusion segments (SSS≥1) were found, which was mainly (60.3%, 38/63) distributed in myocardial regions supplied by left anterior descending branch (LAD). SSS was positively correlated with age and high density lipoprotein cholesterol (HDLC). SRS, SDS were positively correlated with HDLC and age respectively. Multivariate logistic regression analysis indicated that the female was the only independent risk factor to predict positive MPI (odds ratio=5.2, 95% CI: 1.363-19.774). Conclusions In HoFH patients, abnormal myocardial perfusion had a rising trend with age increasing. Female patients are more likely to have abnormal MPI. Abnormal myocardial perfusion segments are mainly located in myocardial regions supplied by LAD. Age and gender are influence factors of abnormal MPI in HoFH patients. Key words: Hyperlipoproteinemia type Ⅱ; Homozygote; Myocardial perfusion imaging; Tomography, emission-computed, single-photon; Technetium Tc 99m sestamibi

TCT-224 Long-term Clinical Outcomes of Medical Therapy Versus Coronary Revascularisation in Patients with Intermediate Stenoses Guided by Pressure Wire

Background: Extent and severity of myocardial hypoperfusion correlates with patient outcome in CHD. The nuclear substudy of COURAGE indicates patients with ischaemia 10% total myocardial volume benefit from PCI. Radionuclide perfusion imaging allows complete myocardial coverage throughout the R-R interval with tracer uptake regionally distributed in proportion to blood flow. Cardiac Magnetic Resonance (CMR) perfusion sequences provide myocardial coverage at discrete time periods in the cardiac cycle. Myocardial blood flow varies during the cardiac cycle and may impact upon how accurately different perfusion imaging techniques quantify physiologically significant ischaemia. Methods: Simultaneous pressure wire and coronary catheter pressure recordings were sampled in 22 patients. Instantaneous Fractional Flow Reserve (iFFR) and Rest TransStenotic Pressure Ratios (iRTPR) were interrogated at 5 millisecond (ms) intervals. Analysis of these indices were performed representative of Single Photon Emission Computerised Tomography (SPECT) and CMR myocardial perfusion sequences. Comparison with conventional FFR (cFFR) and conventional RTPR (cRTPR) were assessed. Results: Maximum iFFR differed from minimum iFFR by 0.20 / 0.17 over 234 / 131ms. Similarly maximum iRTPR differed from minimum by 0.16 / 0.13 over 247 / 136ms. Difference between maximum and minimum iFFR and iRTPR correlated with cFFR(r 0.85) and cRTPR(r 0.97) respectively. For SPECT, the ratio of cFFR to cRTPR moderately correlated with cFFR(r 0.58). For CMR, hypothetical phase specific slice averaged iFFR differed from cFFR by 0.08 / 0.09 and iRTPR from cRTPR by 0.05 / 0.08 in the diastolic period. The largest difference between period averaged iFFR & iRTPR values was 0.08 / 0.10 and occurred at lower cFFR & cRTPR values during the diastolic period. Conclusions: iFFR, iRTPR, and the difference and ratio between each varies during the cardiac cycle. This has considerable implication for quantification of physiologically significant total myocardial ischaemic burden by myocardial perfusion imaging, particularly pertinent to CMR. Variation of tracer uptake during the cardiac cycle may aid diagnosis in the setting of balanced ischaemia when adopting SPECT.

Comparison of radionuclide myocardial perfusion imaging and multilayer spiral CT in the diagnosis of 36 patients with coronary artery disease

Objective To compare the clinical effect of radionuclide myocardial perfusion imaging(SPECT)and multilayer spiral CT coronary artery imaging(MSCT) in the diagnosis of coronsry artery disease(CHD).Methods The clinical data of 36 patients suspected with CHD and routine inspection of SPECT and MSCT were retrospectively analyzed.The diagnostic effects of two methods were compared.Results The sensitivity,specificity and the rate of accuracy of SPECT was 89.47％,94.12％,and 91.67％,respectively,while the sensitivity,specificity and the rate of accuracy of MSCT was 84.21％,94.12％,and 88.89％,respectively.There were no obvious difference in two groups (x2 =1.265,1.668,2.005,1.526,1.889,all P ＞ 0.05 ).Conclusion There was a high degree consistency on the diagnosis of CHD between SPECT and MSCT.In the application,combined with the two methods could improve the diagnosis of CHD. Key words: Coronary artery disease; Radionuclide myocardial perfusion imaging; Multilayer spiral CT coronary artery imaging

Cardiac CT for the assessment of chest pain: Imaging techniques and clinical results

Immediate and efficient risk stratification and management of patients with acute chest pain in the emergency department is challenging. Traditional management of these patients includes serial ECG, laboratory tests and further on radionuclide perfusion imaging or ECG treadmill testing. Due to the advances of multi-detector CT technology, dedicated coronary CT angiography provides the potential to rapidly and reliably diagnose or exclude acute coronary artery disease. Life-threatening causes of chest pain, such as aortic dissection and pulmonary embolism can simultaneously be assessed with a single scan, sometimes referred to as “triple rule out” scan. With appropriate patient selection, cardiac CT can accurately diagnose heart disease or other sources of chest pain, markedly decrease health care costs, and reliably predict clinical outcomes. This article reviews imaging techniques and clinical results for CT been used to evaluate patients with chest pain entering the emergency department.

The feasibility and accuracy of enhanced MR pulmonary perfusion imaging in evaluating therapeutic effect of pulmonary embolism

Objective To investigate the feasibility and accuracy of enhanced magnetic resonance pulmonary perfusion imaging(MRPP) in the diagnosis and follow-up of pulmonary embolism(PE). Methods Sixty patients suspected of PE underwent MRPP. Twenty-seven patients also underwent radionuclide perfusion imaging. 22 patients repeated MRPP examination after 3 day to 1 month anticoagulation or thrombolytic therapy. The feasibility and accuracy of MRPP in the diagnosis and follow-up of PE were evaluated according to the transformation rate of signal (TROS), time-signal curve and some parameters of main pulmonary artery(such as peak value of flow,mean flow velocity and flow rate). The t test and rank sum test were used for the statistics. Results MRPP showed a high agreement with radionuclide perfusion imaging. TROS was (2. 86 ± 2. 48 ) vs ( 6. 72 ± 2. 54) ( t = 3. 370, P ＜ 0. 01 ), the peak time was ( 13.98 ±5.60) vs ( 12. 33 ± 3.63 ) s ( t = 3. 930, P ＜ 0. 01 ), the peak value of main pulmonary blood flow was (60.39 ± 15. 17) vs (69.93±13.22) cm/s(t=2.930, P＜0. 01) and mean flow velocity (11.68±5.46) vs ( 13.54 ± 4. 18 ) cm/s ( t = 2. 380, P ＜ 0. 05 ) before and after anticoagulation or thrombolytic therapy. The flow rate per unit was (80. 57 ± 24. 87) vs ( 85.48 ± 11.81 ) ml/s ( t = 0. 86,P ＞ 0. 05 ) . Conclusion MRPP shows a high agreement with radionuclide perfusion imaging and is a useful method for the diagnosis and follow-up of PE. Key words: Pulmonary embolism; Magnetic resonance angiography; Radionuclide imaging

CT perfusion angiography; beware of artifacts!

CT perfusion angiography; beware of artifacts!

Detection of coronary artery disease with perfusion stress echocardiography using a novel ultrasound imaging agent: two Phase 3 international trials in comparison with radionuclide perfusion imaging

To determine if perfusion stress echocardiography (PSE) with Imagify (perflubutane polymer microspheres) is comparable to stress perfusion imaging using (99m)Tc single photon emission computed tomography (SPECT) for coronary artery disease (CAD) detection. PSE is a novel technique for evaluating myocardial perfusion. RAMP (real-time assessment of myocardial perfusion)-1 and -2 were international, Phase 3 trials that evaluated the ability of PSE with Imagify, to detect CAD. Chronic, stable, chest pain patients (n=662) underwent Imagify PSE and gated SPECT imaging at rest and during dipyridamole stress. Independent blinded cardiologists [three PSE readers per trial, and four SPECT readers (one for RAMP-1, three for RAMP-2)] interpreted images. CAD was defined by quantitative coronary angiography or 90-day outcome with clinical review. Accuracy, sensitivity, and specificity were evaluated using non-inferiority analysis (one-sided alpha=0.025) compared with SPECT. SPECT results for RAMP-1 and -2 were: accuracy (70%, 67%), sensitivity (78%, 61%), and specificity (64%, 76%). Accuracy of all six PSE readers was non-inferior to SPECT (66-71%, P<or=0.004). Four demonstrated non-inferior sensitivity (68-77%, P<or=0.002), three demonstrated non-inferior specificity (72-88%, P<or=0.013). Three PSE readers (RAMP-2) were superior for sensitivity. Two PSE readers (RAMP-1) were superior for specificity. Area under the multi-reader receiver operating characteristics curve (0.72) was equal for both modalities. Majority of adverse events followed dipyridamole dosing, and were mild, transient, and required no treatment. Imagify PSE was well-tolerated. Its diagnostic performance in chest pain patients is comparable with SPECT perfusion imaging.

Coronary CT angiography in emergency department patients with acute chest pain: triple rule-out protocol versus dedicated coronary CT angiography

Immediate coronary catheterization is mandatory for high risk patients with typical chest pain in the emergency department (ED). In contrast, in ED patients with acute chest pain but low to intermediate risk, traditional management protocol includes serial ECG, cardiac troponins and radionuclide perfusion imaging. However, this protocol is time-consuming and expensive, and definite treatment of unstable angina is often delayed. Due to advances of multi-detector CT (MDCT) technology, dedicated coronary CT angiography provides the potential to rapidly and reliably diagnose or exclude acute coronary syndrome in ED patients with acute chest pain. Moreover, major life-threatening causes of ED chest pain (i.e., acute aortic syndrome and pulmonary embolism as well as acute coronary syndrome) can simultaneously be assessed by the so-called "triple rule-out" protocol with a single scan. In ED patients with atypical chest pain and low to intermediate risk, the triple rule-out protocol may be preferred, especially in older patients who have relatively lower risk of lifelong radiation-induced cancer. However, the increased radiation dose resulting from the extended volume coverage with this protocol should be fully considered prior to performing this protocol. Therefore, in ED patients who have a low clinical suspicion of pulmonary embolism and acute aortic syndrome, especially younger patients, dedicated coronary CT angiography accompanied by modifications to reduce radiation dose is recommended.

Stress Echocardiography Expert Consensus Statement--Executive Summary: European Association of Echocardiography (EAE) (a registered branch of the ESC)

Stress echocardiography is the combination of echocardiography with a physical, pharmacological, or electrical stress. The diagnostic endpoint for the detection of myocardial ischaemia is the induction of a transient worsening in regional function during stress. Stress echocardiography provides similar diagnostic and prognostic accuracy to radionuclide stress perfusion imaging, but at a substantially lower cost, without environmental impact, and with no biohazards for the patient and the physician. Among different stresses of comparable diagnostic and prognostic accuracy, semisupine exercise is the most used, dobutamine the best test for viability, and dipyridamole the safest and simplest pharmacological stress and the most suitable for combined wall motion coronary flow reserve assessment. The additional clinical benefit of myocardial perfusion contrast echocardiography and myocardial velocity imaging has been inconsistent to date, whereas the possibility of performing coronary flow reserve evaluation of the left anterior descending coronary artery by transthoracic Doppler echocardiography adds another potentially important dimension to stress echocardiography. New emerging fields of application taking advantage of the versatility of the technique are Doppler stress echo in valvular heart disease and in dilated cardiomyopathy. In spite of its dependence on the operator's training, stress echocardiography is today the best (most cost-effective and risk-effective) possible imaging choice to achieve the still elusive target of sustainable cardiac imaging in the field of non-invasive diagnosis of coronary artery disease. In 1935, Tennant and Wiggers1 demonstrated that coronary occlusion immediately resulted in instantaneous abnormality of wall motion. A large body of evidence2–5 recognized for the first time that transient dys-synergy was an early, sensitive, specific marker of transient ischaemia, clearly more accurate than ECG changes and pain. In European clinical practice,6–10 stress echo has been embedded in the legal and cultural framework of existing European laws and medical imaging referral guidelines. The …

Early diagnosis of pulmonary embolism after thoracic injury or surgery

Objective To evaluate experience for early diagnosis of pulmonary tembolism alter thoracic injury or surgery. Methods The 9 patients after thoracic injury or surgery with highly-suspected pulmonary embolism underwent chest radiograph of X-ray, helical CT pulmonary angiography, electrocardiogram, radionuclide pulmonary ventilation perfusion imaging, D dimer assay and arterial blood gas analysis respectively and the clinic data and results were analyzed. Results All patients were diagnosed and recovered after 8 patients received thrombolytic therapy and another patient received anticoagulant therapy. Conclusion If there were some symptoms such as suddenly severe dyspnea, cyanosis, with/without chest pains and the feeling of fear to death unable to be explained by original disease on those patients alter thoracic injury or surgery, it's very important for pulmonary embolism to be recognized, and early diagnosis and quickly efficient treatment is the key to prevent death. Helical CT pulmonary angiography is a safe, cheap, noninvasive and effective method for the diagnosis of pulmonary embolism with high sensitivity and specificity. Key words: Pulmonary tembolism; Surgical procedures; operative; Tomography; sprial computed; Angiocardiograhy; Early diagnosis

Stress echocardiography expert consensus statement: European Association of Echocardiography (EAE) (a registered branch of the ESC)

Stress echocardiography is the combination of 2D echocardiography with a physical, pharmacological or electrical stress. The diagnostic end point for the detection of myocardial ischemia is the induction of a transient worsening in regional function during stress. Stress echocardiography provides similar diagnostic and prognostic accuracy as radionuclide stress perfusion imaging, but at a substantially lower cost, without environmental impact, and with no biohazards for the patient and the physician. Among different stresses of comparable diagnostic and prognostic accuracy, semisupine exercise is the most used, dobutamine the best test for viability, and dipyridamole the safest and simplest pharmacological stress and the most suitable for combined wall motion coronary flow reserve assessment. The additional clinical benefit of myocardial perfusion contrast echocardiography and myocardial velocity imaging has been inconsistent to date, whereas the potential of adding - coronary flow reserve evaluation of left anterior descending coronary artery by transthoracic Doppler echocardiography adds another potentially important dimension to stress echocardiography. New emerging fields of application taking advantage from the versatility of the technique are Doppler stress echo in valvular heart disease and in dilated cardiomyopathy. In spite of its dependence upon operator's training, stress echocardiography is today the best (most cost-effective and risk-effective) possible imaging choice to achieve the still elusive target of sustainable cardiac imaging in the field of noninvasive diagnosis of coronary artery disease.

Do Men and Women Differ on Measures of Mental Stress-Induced Ischemia?

To consider the effects of gender on ischemia in a larger sample, with broadly defined coronary artery disease (CAD). Mental stress has been shown to cause transient myocardial ischemia in a significant percentage of people with CAD. However, little is known about the effects of mental stress on ischemic processes in women. Most studies to date either had few women or required a positive exercise stress test. Participants (61 women, 93 men; average age = 63 years) had documented CAD (positive stress test, abnormal catheterization even with minimal disease, or previous myocardial infarction). They underwent mental stress testing and radionuclide perfusion imaging (stress/ rest). Cardiac function data were collected and stress was compared with baseline. The data were then submitted to a series of analyses of variance. A total of 50 (32%) participants exhibited reversible ischemia post psychological stress. This reflects a relative rate of 33% (n = 31 of 93) for men and 31% (n = 19 of 61) for women. No difference between men and women were observed on any measure of hemodynamic functioning (blood pressure, heart rate, or cardiac perfusion). Results of this study showed no significant differences between men and women on measures of hemodynamic functioning or cardiac perfusion.

Screening for Coronary Artery Disease After Mediastinal Irradiation for Hodgkin's Disease

Incidental cardiac irradiation during treatment of thoracic neoplasms has increased risks for subsequent acute myocardial infarction or sudden cardiac death. Identifying patients who have a high risk for a coronary event may decrease morbidity and mortality. The objective of this study was to evaluate whether stress imaging can identify severe, unsuspected coronary stenoses in patients who had prior mediastinal irradiation for Hodgkin's disease. We enrolled 294 outpatients observed at a tertiary care cancer treatment center after mediastinal irradiation doses 35 Gy for Hodgkin's disease who had no known ischemic cardiac disease. Patients underwent stress echocardiography and radionuclide perfusion imaging at one stress session. Coronary angiography was performed at the discretion of the physician. Among the 294 participants, 63 (21.4%) had abnormal ventricular images at rest, suggesting prior myocardial injury. During stress testing, 42 patients (14%) developed perfusion defects (n = 26), impaired wall motion (n = 8), or both abnormalities (n = 8). Coronary angiography showed stenosis 50% in 22 patients (55%), less than 50% in nine patients (22.5%), and no stenosis in nine patients (22.5%). Screening led to bypass graft surgery in seven patients. Twenty-three patients developed coronary events during a median of 6.5 years of follow-up, with 10 acute myocardial infarctions (two fatal). Stress-induced signs of ischemia and significant coronary artery disease are highly prevalent after mediastinal irradiation in young patients. Stress testing identifies asymptomatic individuals at high risk for acute myocardial infarction or sudden cardiac death.

Below Radar

Below Radar

Evaluation of Patients with Chest Pain who Present to the Emergency Department: Utility of Multidetector CT

SummaryThe evaluation of patients who present to the Emergency Department with chest pain remains challenging, particularly for atypical chest pain. This article discusses imaging techniques that are used in such equivocal cases, including radionuclide perfusion imaging and echocardiography, with emphasis on the potential role of multi‐detector computed tomography.