Michael K. Atalay

ACR Appropriateness Criteria® acute chest pain--suspected pulmonary embolism.

Pulmonary embolism (PE) remains a common and important clinical condition that cannot be accurately diagnosed on the basis of signs, symptoms, and history alone. In the absence of high pretest probability and with a negative high-sensitivity D-dimer test, PE can be effectively excluded; in other situations, diagnostic imaging is necessary. The diagnosis of PE has been facilitated by technical advancements and multidetector computed tomography pulmonary angiography, which is the major diagnostic modality currently used. Ventilation and perfusion (V/Q) scans remain largely accurate and useful in certain settings. Lower-extremity ultrasound can substitute by demonstrating deep vein thrombosis; however, if negative, further studies to exclude PE are indicated. In all cases, correlation with the clinical status, particularly with risk factors, improves not only the accuracy of diagnostic imaging but also overall utilization. Other diagnostic tests have limited roles. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The development and review of the guidelines include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

The Prevalence and Clinical Significance of Noncardiac Findings on Cardiac MRI

OBJECTIVE This study aims to evaluate the prevalence, nature, and clinical significance of noncardiac findings (NCFs) at cardiac MRI. MATERIALS AND METHODS We retrospectively reviewed 240 consecutive, clinically indicated cardiac MRI examinations conducted over a 21-month period. All noncardiac findings (NCFs) were recorded. Those findings that were included in the report impressions were regarded as clinically important (INCF). Electronic medical records and related imaging studies were then reviewed for all patients having INCFs to determine their actual clinical significance. A finding was significant (SNCF) if it was associated with a new diagnosis, treatment, or intervention. The prevalences of findings in the neck, chest, and abdomen were determined. RESULTS We found 162 NCFs in 104 studies (43%), of which 94 (58%) were INCFs, and 16 (10%) were SNCFs. There was at least one INCF in 65 studies (27%)--67% of which were new--and at least one SNCF in 13 studies (5%). Compared with younger patients, patients 60 years and older were much more likely to have INCFs (43% vs 17%) and SNCFs (12% vs 1%). Overall, 29% of NCFs were in the abdomen, 70% in the chest, and 1% in the neck. The most common INCFs were pleural effusion (n = 26), air-space disease or atelectasis (n = 13), and adenopathy (n = 9). Five new cases of cancer were diagnosed, including lung (n = 2), lymphoma (n = 2), and thyroid (n = 1). CONCLUSION NCFs are commonly encountered on cardiac MRI studies, many of which are clinically relevant. Proper recognition of NCFs is critical to the comprehensive management of patients referred for cardiac MRI.

Clinical myocarditis masquerading as acute coronary syndrome.

We report a series of children with clinical myocarditis presenting with chest pain and elevated cardiac troponin I mimicking coronary syndrome. Our series illustrates the complementary role the magnetic resonance imaging and computed tomographic angiography can play in the evaluation of these patients. Elevated cardiac troponin I levels were found to be related to the extent of myocardial involvement, but did not necessarily indicate poor prognosis in children with myocarditis.

Quantitative Assessment of Right Ventricular Volumes and Ejection Fraction in Patients with Left Ventricular Systolic Dysfunction by Real Time Three-Dimensional Echocardiography versus Cardiac Magnetic Resonance Imaging

The aim of this study was to assess the accuracy and reproducibility of real time three‐dimensional echocardiographic (RT3DE) for the determination of right ventricular (RV) volumes and function in patients with left ventricular (LV) systolic dysfunction.

ACR Appropriateness Criteria® Chronic Chest Pain—High Probability of Coronary Artery Disease

Imaging is valuable in determining the presence, extent, and severity of myocardial ischemia and the severity of obstructive coronary lesions in patients with chronic chest pain in the setting of high probability of coronary artery disease. Imaging is critical for defining patients best suited for medical therapy or intervention, and findings can be used to predict long-term prognosis and the likely benefit from various therapeutic options. Chest radiography, radionuclide single photon-emission CT, radionuclide ventriculography, and conventional coronary angiography are the imaging modalities historically used in evaluating suspected chronic myocardial ischemia. Stress echocardiography, PET, cardiac MRI, and multidetector cardiac CT have all been more recently shown to be valuable in the evaluation of ischemic heart disease. Other imaging techniques may be helpful in those patients who do not present with signs classic for angina pectoris or in those patients who do not respond as expected to standard management. The ACR Appropriateness Criteria(®) are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Cardiac magnetic resonance imaging: a new tool to identify cardioaortic sources in ischaemic stroke

Stroke of undetermined aetiology or ‘cryptogenic’ stroke accounts for 30–40% of ischaemic strokes despite extensive diagnostic evaluation. The role and yield of cardiac imaging is controversial. Cardiac MRI (CMR) has been used for cardiac disorders, but its use in cryptogenic stroke is not well established. We reviewed the literature (randomised trials, exploratory comparative studies and case series) on the use of CMR in the diagnostic evaluation of patients with ischaemic stroke. The literature on the use of CMR in the diagnostic evaluation of ischaemic stroke is sparse. However, studies have demonstrated a potential role for CMR in the diagnostic evaluation of patients with cryptogenic stroke to identify potential aetiologies such as cardiac thrombi, cardiac tumours, aortic arch disease and other rare cardiac anomalies. CMR can also provide data on certain functional and structural parameters of the left atrium and the left atrial appendage which have been shown to be associated with ischaemic stroke risk. CMR is a non-invasive modality that can help identify potential mechanisms in cryptogenic stroke and patients who may be targeted for enrolment into clinical trials comparing anticoagulation to antiplatelet therapy in secondary stroke prevention. Prospective studies are needed to compare the value of CMR as compared to transthoracic and transesophageal echocardiography in the diagnostic evaluation of cryptogenic stroke.

Left Main Pseudoaneurysm After Postpartum Coronary Dissection

The patient is a 34-year-old woman, para 3, gravida 3, with dyslipidemia and former tobacco use, who 1-week postpartum experienced an acute myocardial infarction. Initial angiography revealed a left main (LM) artery dissection with probable subintimal hematoma extending into the proximal left anterior descending (LAD) and left circumflex (LCX) coronary arteries (Figure 1A). Left ventriculography revealed anterior and apical akinesis with an ejection fraction of 30%. Because definitive therapy with percutaneous revascularization carries the risk of dissection extension and occlusion and because there was minimal luminal encroachment and TIMI (thombolysis in myocardial infarction) flow grade 3, we elected for medical therapy, including aspirin, and further observation. Also controversially, we elected not to anticoagulate because of the theoretical potential to maintain false lumen patency. Figure 1. A , Initial angiography suggests left main coronary dissection (X). Narrowing of the proximal left ascending (Y) and proximal left circumflex (Z) coronary artery segments compared to the corresponding midsegments suggests intramural hematoma. B , Surveillance angiography 1 week later reveals clear extension of dissection into left circumflex artery and near obliteration of the mid-left ascending artery (arrow). Because of the high-risk nature of the problem and the unpredictable natural history, surveillance angiography 1 week after myocardial infarction was performed and revealed obvious progression of the LM dissection flap into the proximal LAD and LCX arteries, with significant luminal narrowing and TIMI 2 flow in the LAD artery (Figure 1 …

Multimodal Imaging after Sudden Cardiac Arrest in an 18-Year-Old Athlete.

We report the case of a previously healthy 18-year-old male athlete who twice presented with sudden cardiac arrest. Our use of electrocardiography, echocardiography, cardiac magnetic resonance, coronary angiography, coronary computed tomographic angiography, and nuclear stress testing enabled the diagnoses of apical hypertrophic cardiomyopathy and anomalous origin of the right coronary artery. We discuss the patients treatment and note the useful role of multiple cardiovascular imaging methods in cases of sudden cardiac arrest.

The Transaxial Orientation Is Superior to Both the Short Axis and Horizontal Long Axis Orientations for Determining Right Ventricular Volume and Ejection Fraction Using Simpson's Method with Cardiac Magnetic Resonance

We sought to determine which of the three orientations is the most reliable and accurate for quantifying right ventricular (RV) volume and ejection fraction (EF) by cardiac magnetic resonance using Simpsons method. We studied 20 patients using short axis (SA), transaxial (TA), and horizontal long axis (HLA) orientations. Three readers independently traced RV endocardial contours at end-diastole and end-systole for each orientation. End-diastolic volumes (EDVs), end-systolic volumes (ESVs), and EF were calculated and compared with the 3D piecewise smooth subdivision surface (PSSS) method. The intraclass correlation coefficients among the 3 readers for EDV, ESV, and EF were 0.92, 0.82, and 0.42, respectively, for SA, 0.95, 0.92, and 0.67 for TA, and 0.85, 0.93, and 0.69 for HLA. For mean data there was no significant difference between TA and PSSS for EDV (−2.6%, 95% CI: −8.2 to 3.3%), ESV (−5.9%, −15.2 to 4.5%), and EF (1.7%, −1.5 to 4.9%). HLA was accurate for ESV (−8.9%, −18.5 to 1.8%) and EF (−0.7%, −3.8 to 2.5%) but significantly underestimated EDV (−9.8, −16.6 to −2.4%). SA was accurate for EDV (0.5%, −6.0 to 7.5%) but overestimated ESV (10.5%, 0.1 to 21.9%) and had poor interrater reliability for EF. Conclusions. The TA orientation provides the most reliable and accurate measures of EDV, ESV, and EF.

Familial pseudocoarctation of the aorta.

Pseudocoarctation of the aorta (PCOA) is an unusual congenital malformation of the aortic arch characterized by an acute anterior angulation of the aortic arch at the level of the ligamentum arteriosum with little or no obstruction. This report describes the occurrence of PCOA and other aortic arch abnormalities including true coarctation, right aortic arch, and aneurysms of the proximal and distal aortic arch in three generations of a single family. To our knowledge, a familial form of PCOA has not been described.