ACR Clinical Statement on Noninvasive Cardiac Imaging

PERIOPERATIVE myocardial complications after noncardiac surgery affect more than 1 million operations each year and are leading causes of morbidity and mortality, especially among patients undergoing vascular surgery. Myocardial complications such as perioperative myocardial infarction (MI) are common and are the most likely cause for perioperative death in all surgical populations.1In general surgery, the risk for perioperative MI is 0.8% in men older than 50 yr2and varies with the cardiovascular status, comorbidities, and the extent of the procedure, reaching more than 20% among patients undergoing vascular surgery.3As patients become older and sicker and procedures become more aggressive and extensive, physicians must find novel approaches to evaluate and prepare cardiac patients for noncardiac procedures and reduce perioperative myocardial events.The American Heart Association–American College of Cardiology guidelines for cardiac risk evaluation use the patient's history, physical examination, and functional capacity, and taking into account the expected surgery, one may recommend further assessment with noninvasive testing or coronary angiography.4The purpose of this review is to provide an overview of available imaging tools that could potentially be used for perioperative evaluation of cardiac patients before noncardiac surgery, in accord with recent guidelines and with focus on the recent progress made with cardiac computed tomography (CT).Traditionally, preoperative evaluation has relied on the patient's history, physical examination, and functional capacity. After preoperative evaluation, the physician should determine the clinical predictors as major, intermediate, or minor4and evaluate the functional capacity of the patient. New York Heart Association class II heart failure, which equals 4 metabolic equivalents,4has also been found to be an important predictor of perioperative cardiac complications after major noncardiac surgery. The cutoff value of 4 or more metabolic equivalents determines an adequate cardiac functional capacity and reserve and predicts perioperative cardiac events in patients treated with high-risk noncardiac surgery.5Finally, the extent and risk associated with the procedure should be categorized as major, intermediate, or minor. The cardiac risk is the combined incidence of cardiac death and nonfatal MI and is greater than 5% for high-risk procedures, whereas intermediate-risk procedures have less than 5% cardiac risk (1–5%), and low-risk procedures have less than 1% cardiac risk.4Indeed, based on these criteria, the flowchart of Eagle et al. 4suggests when a noninvasive test or coronary angiography may be appropriate to evaluate cardiac function, reserve, or ability to withstand surgical stress. Pertinent to the utility of evaluating cardiac structure and function, new imaging techniques for evaluation of the heart have emerged in the past couple of decades. These techniques may provide more comprehensive information regarding the structure and function of the heart and coronary arteries, and evaluate adequately patients who have mechanical restrictions to perform exercise-induced stress. Such developments in cardiac imaging may eventually provide an opportunity to revise and refine the steps involving the evaluation of cardiac patients.6,7This approach should be evaluated cautiously and should take into consideration recent recommendations and guidelines. For example, the current American Heart Association–American College of Cardiology guidelines recommend the use of perioperative β-blocker therapy as an alternative approach to decrease cardiovascular risk.8β-Blockers initiated at least 1 week before major vascular surgery and continued for 30 days postoperatively reduced significantly the perioperative incidence of nonfatal MI and death from cardiac causes in high-risk patients.9In addition to beta blockers, statins may reduce perioperative mortality in patients undergoing major vascular surgery and may have an additive effect to β-blockers.10,11The strategy of preoperative coronary artery revascularization before elective major vascular surgery to reduce perioperative cardiac morbidity and mortality was investigated in the Coronary Artery Revascularization Prophylaxis trial, a multicenter study involving patients with vascular disease and significant coronary artery disease (CAD), but no unstable angina. Cardiac revascularization did not result in increased survival, either perioperatively or in long-term follow-up, in patients who needed elective vascular surgery.12However, although the Coronary Artery Revascularization Prophylaxis study is a cornerstone trial in the perioperative care of cardiac patients for noncardiac surgery, it had some limitations. In particular, only 9% of the patients scheduled to undergo vascular operations were eligible for the study. The main reasons for exclusion were insufficient cardiac risk, an urgent vascular surgery, previous revascularization without ischemia, severe coexisting illnesses, left main coronary artery stenosis of at least 50%, left ventricular ejection fraction less than 20%, and severe aortic stenosis. The outcome of these patients has not been adequately evaluated.Indeed, taking into consideration the patient's perioperative cardiac risk according to clinical predictors, functional capacity, and the extent of the future surgery, the anesthesiologist must decide whether further cardiac assessment or perioperative medical management are indicated. Patients whose functional capacity is difficult to establish, who underwent previous coronary revascularization, who have unstable or changed cardiac status, or who have severe comorbidities may need further evaluation. Several imaging techniques are available for evaluation of cardiac patients, including cardiac CT, coronary angiography, stress echocardiography, cardiac magnetic resonance imaging (CMRI), and myocardial nuclear studies.Computed tomography is widely available in large medical centers and is routinely used in clinical practice. The basic principle of CT is that a fan-shaped, thin x-ray beam passes through the body at many angles to allow for cross-sectional images. After collimation of the beam (i.e. , achieving a definitive slice thickness using a collimator) to reduce scatter, the photons are recorded on a corresponding detector array, and the transmission data are digitized. A “filtered back projection” reconstruction algorithm, which takes into account the attenuation of the x-ray beam along its path, allows for reconstruction of the grayscale values of each picture element (pixel) with reference to the value for water and air, to depict cross-sectional images. Reconstruction algorithms and multirow detectors applied in current scanners enable three-dimensional volumetric imaging and multiple high-quality reconstructions of various volumes of interest.13Current clinical scanners used for cardiovascular imaging employ either a rotating x-ray source with a circular, stationary detector array (e.g. , helical CT) or electromagnetic deflection of an electron beam to replace mechanical motion (electron beam computed tomography [EBCT]).14Multidetector computed tomography (MDCT) is a helical CT with a large array of detectors, which allow it to acquire a large number of slices simultaneously (4–256) and greatly increase its resolution. However, to obtain quantitative measurements of tissue opacity within a specific cardiac phase (e.g. , for measurement of perfusion), the scanning time should generally be less than 100 ms.15Sufficiently high temporal resolution (the time required to acquire the data for one image) is currently offered only by the EBCT (50 ms/image) and the novel Dual-Source CT (SOMATOM® Defi-nition; Siemens Medical Systems, Forchheim, Germany) (83 ms/image), a recently released model of MDCT that has two x-ray tubes (rather than one) positioned at 90° to each other, thereby doubling temporal resolution.16However, this technique remains to be validated for such measurements.Electron beam computed tomography was developed in the 1980s and hailed as an ultimate cardiac scanner. It allows almost simultaneous data acquisition from up to eight parallel slices (7–8 mm thick) by rapid sweeping of an electron beam along target rings in as little as 50 ms per scan. Because it does not involve moving parts (and therefore decreases the need for cooling), the speed of acquisition (temporal resolution) with EBCT is faster than with MDCT (table 1) and usually does not require slowing the heart rate pharmacologically. The high speed of EBCT is offset by moderate image quality and relatively restricted power for acquisition of a large number of images, which decreased its popularity for comprehensive cardiac studies. Consequently, its availability is limited, resulting in declining use of this technology.Multidetector computed tomography is a relatively ubiquitous and newer scanner that has temporal resolution of 330–400 ms/image, which enables many studies of cardiac anatomy and global function (e.g. , ejection fraction and cardiac output). Spatial resolution can be achieved with 64-slice scanners using isotropic voxels (consistent three-dimensional image quality in any reconstruction plane) of 0.4 × 0.4 × 0.4 mm. The technique involves continuous rotation of the x-ray tube and detectors and simultaneous translation of the patient through the gantry opening, and can acquire multiple simultaneous sections of variable widths using prospective electrocardiographic triggering.17Alternatively, retrospective electrocardiographic gating enables reconstruction of images at any desired time in the cardiac cycle. Data can be used from multiple slices to reconstruct other imaging planes. The images are of best quality when the resting heart rate (HR) is less than 70 beats/min. At faster heart rates, motion artifacts may become more prominent, and therefore HR may need to be pharmacologically decreased before scanning. The temporal resolution of MDCT determines the overall scan time. As gantry rotation speeds increase, the minimum slice thickness decreases, with submillimeter sections throughout the heart acquired during a single breath hold. The overall CT scan time is approximately 12 s, and the mean total time for the examination is less than 13 min with 64-slice technology.The improvement in MDCT technology enabled the assessment of significant luminal stenosis and identification of nonstenotic atherosclerotic plaques. Virtual noninvasive angiography, with three-dimensional reconstruction of coronary anatomy from cardiac CT images, can provide information about coronary luminal obstruction, calcium scoring, and composition of the plaque.18Furthermore, it has the added benefit of offering fine details of the examined vessels (fig. 1).Excellent sensitivity and specificity were found for evaluation of proximal, middle and distal left anterior descending, first diagonal, proximal and distal circumflex, obtuse marginal and proximal mid and distal right coronary artery.19A meta-analysis of diagnostic performance of MDCT compared with invasive coronary angiography showed a sensitivity of 85% and a specificity of 95% for identification of CAD. On average, 87% of segments had diagnostic image quality, with a significant increase from 78% with 4-slice systems to 96% with the more recent 16-slice systems.6Multidetector computed tomography could provide a clinically useful tool in the workup of symptomatic patients before angiography.20A patient with chronic chest pain indicative of CAD could undergo CT angiography, and if low calcium score and no circumferential calcifications (or other test results indicative of ischemia) are found, invasive angiography may not be indicated, because MDCT has excellent negative predictive value to rule out CAD. By this approach, patients with primarily microvessel disease (which may cause angina and abnormal stress test results) may be identified and not required to go through unnecessary fluoroscopic angiography, and aggressive medical therapy would be indicated before surgery.20MDCT also has high diagnostic accuracy in detecting bypass graft stenosis and occlusions in symptomatic patients after coronary artery bypass grafting, which might potentially reduce dramatically the number of unnecessary invasive angiographies performed in these patients.21However, although the MDCT technique has been extensively evaluated for its accuracy for detection of CAD compared with standard coronary angiography,6,19,20,22it has not been applied for the routine evaluation of cardiac patients for noncardiac surgery and, to date, is not a recommended technique for perioperative risk stratification.The main technical limitations of cardiac CT for evaluation of the coronary arteries include the difficulty in handling cardiac motion, arrhythmia, severe calcifications, vessel size less than 1.5 mm, breathing, the presence of stents, and poor enhancement.22Lesions with extensive calcified components and implanted coronary stents compromise the accuracy of MDCT coronary angiography by causing artifacts.23Stent type and diameter influence evaluability of in-stent restenosis by MDCT, but in evaluable stents, sensitivity is still 86% and specificity is 98%.24When HR is reduced below 70 beats/min, image quality is improved, especially in terms of the visualization of the right coronary and left circumflex arteries, which are both significantly prone to motion artifacts (particularly at higher HR) because of their close proximity to the atrium, which is reactivated during the early diastolic phase.25For evaluation of coronary artery calcium volume with MDCT, thin-slice retrospective spiral electrocardiographic–gated scanning is desirable.26Most studies on coronary calcification have been performed using EBCT, which is still considered the “gold standard” (table 1). To image the coronary arteries with EBCT, 30–40 axial images are obtained with 3-mm slice thickness, using single-slice prospective electrocardiographic triggering in the craniocaudal direction along the full length of the heart. Rapid image acquisition at 100 ms allows accurate measurement of calcium deposits in the coronary arteries.27Quantification of coronary artery calcifications was found to be independently associated with cardiac events in a 3-yr follow-up of thousands of initially asymptomatic patients.28Noninvasive characterization and quantification of atherosclerotic plaque burden may also have important implications for the prevention of CAD progression and its complications.18For the past several years, CMRI has been considered the reference standard for assessment of left ventricular (LV) functions. However, cardiac CT is playing an increasingly important role in this evaluation. Both CT and CMRI surpass two-dimensional imaging techniques, such as standard two-dimensional echocardiography, for cardiac quantification because of their ability to generate contiguous short axis cine images, allowing for three-dimensional measurements without the use of geometric assumptions.29Postprocessing tools allow fast and semiautomatic determination of LV function parameters from MDCT data in analogy to known CMRI evaluation approaches.30Studies have demonstrated excellent correlation between cardiac CT and CMRI for LV ejection fraction, end-diastolic volume, end-systolic volume, stroke volume, and myocardial mass.30Furthermore, global and regional LV functions agree well with echocardiography, with correlation coefficients ranging from 0.91 to 0.97 for MDCT and from 0.93 to 0.98 for CMRI.7,30,31Although MDCT is not considered to be the first-line modality for assessment of LV function, it can provide a combined assessment of cardiac morphology and function without the need for additional radiation exposure in patients undergoing MDCT coronary angiography. The acquisition of images is performed according to the R–R interval. For MDCT, the image data are gated with the electrocardiogram to allow reconstruction at various times throughout the cardiac cycle. CT allows quantitative analysis of regional and global systolic function in normal and pathologic conditions by using short axis slices from the base to the apex of the heart. End-diastole and end-systole are defined as maximal and minimal LV volume, and LV ejection fraction is the difference between them.30Diastolic function can also be assessed from the rate of change of the LV volume during diastole.13Also, because temporal resolution for electrocardiographic-gated cardiac CT scans (down to 165 ms) is poorer in comparison to cine CMRI (30–40 ms), CT imaging may miss peak ejection rate or peak filling rate. However, advances in MDCT imaging that will improve temporal resolution may correct this problem.16Regional wall motion abnormalities, myocardial thinning, ventricular aneurysm, and mural thrombi in the infarcted area can all be detected by cardiac CT. Dual-phase contrast CT can detect acute MI characterized by an initial filling defect and late enhancement at the site of the damaged myocardium. Late enhancement may have the potential to distinguish viable from nonviable myocardium, and has significant prognostic value for the recovery of the myocardial wall motion and thickness after ischemia and in response to therapeutic revascularization.32In patients with previous MI, MDCT permits accurate, noninvasive assessment of coronary artery stenosis, LV function, and perfusion, assessed from a single data set.33If the myocardium supplied by the stenotic or occluded vessel is still viable, medical treatment or revascularization can be considered to reduce the risk of perioperative ischemia in the affected myocardium.Experimental studies in animals and humans demonstrated that cardiac CT could be used to assess microvascular function, although this technique is not used clinically, partially because of high radiation exposure. Evaluation of myocardial perfusion at rest and after infusion of vasodilators imposing cardiac challenge can reveal the presence of otherwise undetectable limited myocardial flow reserve, which might have a significant value for detection of borderline or very early alterations in cardiac microvascular function, as well as detecting increases in microvascular permeability that may reflect endothelial dysfunction or ischemic changes.34The use of CT scanning is limited by the need for contrast media and radiation exposure (table 2). The risks associated with contrast media administration include extravasation at the contrast injection site, allergic contrast reaction, and a decline in function, as well as and vascular In patients with administration of contrast media is media has been reduced and is than that used during angiography potential of alternative contrast such as might further decrease the various radiation are with MDCT, and scanning may allow a decrease in radiation of cardiac function and volumes may from to potentially any based on gated that data several cardiac limitations include the need to image quality in patients and the need for and physicians for acquisition and of cardiac CT data of the limitations of MDCT is the need to decrease heart rate at time of which may be in some It further the need for CT technology to acquisition time a greater volume of developed scanners such as the Dual-Source MDCT may this to temporal the number of that can be from axial CT images is limited only by gantry rotation speed and patient heart decreased ejection fraction in is associated with decreased overall postoperatively and with increased incidence of heart failure, but no has been found with main associated with cardiac events is the presence of wall motion has a low predictive is appropriate in patients who American Heart Association–American College of Cardiology clinical guidelines and who would require if no surgery were as well as in with aortic sensitivity of can be by the heart either or pharmacologically. stress test with administration of can provide information about cardiac function, ventricular and function, and a is in to 85% of maximal HR or or as wall motion abnormalities, whereas a in ejection fraction in response to administration is a of more severe CAD. has excellent negative predictive values and sensitivity but moderate specificity and is significantly and long-term cardiac risk using initial cardiac risk assessment and noninvasive testing with may the perioperative and long-term treatment of patients undergoing major vascular comparison with other noninvasive a diagnostic new of may improve cardiac risk compared with standard in patients undergoing noncardiac surgery whose functional capacity be evaluated by stress stress has a relatively low and can assess cardiac structure and function, wall thickness, aortic and the presence of However, has sensitivity for detection of single vessel disease and is to distinguish between microvascular and CAD (table because wall motion can be found in progress has been made during the past in which is used to evaluate a of heart and including CAD. CMRI is based on the of which and to an magnetic CMRI a causes deflection of the from the direction of the main magnetic The is during the of the back their in the magnetic are and data are used for image many image are for assessment of global ventricular and function, ejection fraction, stroke volume, and detection of and acute and chronic LV can be and using analysis of may find use in the clinical magnetic resonance imaging has higher temporal resolution but resolution (the ability to distinguish between two on the image) than cardiac resolution of 1.5 × 1.5 may have an CMRI for detection of because its overall accuracy in the detection of coronary artery stenosis is higher (table 2). The axial image of MDCT allows more vascular as compared with CMRI that may artifacts to sensitivity and specificity of CMRI for detection of coronary artery stenosis are and whereas of coronary segments are is noninvasive and high-quality images of the heart (table 2). However, CMRI examination be applied in patients who have a or and the presence of and stents can CMRI images and to is the of the test than an during which the patient must be CMRI is an important noninvasive tool and does not the use of potential contrast are needed to evaluate its use as a perioperative tool and its correlation with perioperative cardiac use of myocardial computed tomography and tomography has in the past two because of their in useful information about myocardial perfusion and function based on administration of an unstable with has been used for many for preoperative cardiac evaluation. the coronary response associated with testing not the HR and has been used in patients scheduled to undergo vascular surgery. However, has low and negative predictive and was not significantly associated with the incidence of perioperative MI, ischemia, or other the other the of this test was when used in patients undergoing aortic surgery whose risk could not have been on the of clinical value of imaging for preoperative cardiac assessment in high-risk has been demonstrated in patients before and vascular of myocardial with is important in patients with LV function to and the potential of revascularization can be These studies showed excellent correlation of with cardiac both perioperatively within 30 days and at long-term has high sensitivity in coronary disease but limited sensitivity for detecting significant disease and CAD (table 2). It also little functional data other than myocardial perfusion and has relatively low resolution that the quality of scanners have a maximal of approximately is required for before the performance of myocardial perfusion because the coronary effect of or is by with can be used to functional recovery of viable myocardium after coronary artery a is from a a in and with an results in of both the and the with to in the of electromagnetic radiation of two which in from each and are detected by a of radiation detectors at The difference in time the photons each radiation detector is used to detect the source of the of radiation detectors are in the gantry with million of per the imaging is useful in noninvasive quantification of myocardial flow and coronary flow reserve, and is also of detecting early disease in high-risk asymptomatic and the progression or of is to especially in patients and in undergoing remains a significant its high and limited availability currently its use as a technology of coronary angiography is well and involves injection of contrast media into the coronary artery by imaging in multiple planes. is by comparison of diameter at a stenotic site with that of a normal reference can evaluate coronary stenosis, LV function, and (table coronary angiography is an invasive technique and has a major rate of including mortality in of it may involve for the patient and is associated with other such as vascular complications for diagnostic and for complications and complications the risk of coronary angiography with that of MDCT, some risks are common to both procedures, such as an allergic contrast reaction, and exposure to whereas are to contrast media injection causes severe allergic in of risks of a of for MDCT angiography and for coronary angiography. However, the and risks and a overall risk of mortality from coronary that for MDCT angiography use of a power in a vascular with cardiac CT an additional risk of which in of the relatively significant number of negative invasive angiographies performed each the risks to this procedure by using noninvasive can greatly to the morbidity and mortality of coronary angiography. the number of negative angiographies might to significant because the of cardiac may be as as times that of cardiac evaluation of patients with or known cardiac disease for noncardiac surgery has been in the of of and The preoperative evaluation on assessment of clinical predictors, functional capacity, and the extent of the surgical The first-line to reduce perioperative morbidity and mortality include medical therapy with with HR and However, the strategy may also include of noninvasive imaging techniques that provide comprehensive and assessment of cardiac structure and In particular, in patients with restricted physical in assessment of the functional capacity is obtained using imaging with evaluation of the heart may potentially to treatment Cardiac CT is can provide coronary angiography for plaque assessment and scoring, and can assess LV function, and myocardial in a fast and relatively CT can in out significant CAD and determination of the need for invasive angiography. cardiac CT might potentially be the tool for overall evaluation of cardiac patients for noncardiac surgery. at this is no that preoperative cardiac CT scanning is to reduce perioperative studies are needed to assess the role of cardiac CT in the evaluation of patients at risk for cardiovascular disease before noncardiac surgery.

To develop a cardiac computed tomographic (CT) method with which to determine extracellular volume (ECV) fraction, with cardiac magnetic resonance (MR) imaging as the reference standard. Study participants provided written informed consent to participate in this institutional review board-approved study. ECV was measured in healthy subjects and patients with heart failure by using cardiac CT and cardiac MR imaging. Paired Student t test, linear regression analysis, and Pearson correlation analysis were used to determine the relationship between cardiac CT and MR imaging ECV values and clinical parameters. Twenty-four subjects were studied. There was good correlation between myocardial ECV measured at cardiac MR imaging and that measured at cardiac CT (r = 0.82, P < .001). As expected, ECV was higher in patients with heart failure than in healthy control subjects for both cardiac CT and cardiac MR imaging (P = .03, respectively). For both cardiac MR imaging and cardiac CT, ECV was positively associated with end diastolic and end systolic volume and inversely related to ejection fraction (P < .05 for all). Mean radiation dose was 1.98 mSv ± 0.16 (standard deviation) for each cardiac CT acquisition. ECV at cardiac CT and that at cardiac MR imaging showed good correlation, suggesting the potential for myocardial tissue characterization with cardiac CT.

Cardiac computed tomography (CT) produces high-quality anatomical images of the cardiac valves and associated structures. Cardiac magnetic resonance imaging (MRI) provides images of valve morphology, and allows quantitative evaluation of valvular dysfunction and determination of the impact of valvular lesions on cardiovascular structures. Recent studies have demonstrated that cardiac CT and MRI are important adjuncts to echocardiography for the evaluation of aortic and mitral valvular heart diseases (VHDs). Radiologists should be aware of the technical aspects of cardiac CT and MRI that allow comprehensive assessment of aortic and mitral VHDs, as well as the typical imaging features of common and important aortic and mitral VHDs on cardiac CT and MRI.

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Cardiac magnetic resonance (CMR) imaging is the golden standard used for the diagnosis of cancer therapy-related cardiac dysfunction (CTRCD). The consistency of cardiac computed tomography (CCT) in CTRCD cases using CMR imaging is investigated in this study.Methods and Results:In 7 clinically confirmed CTRCD patients, focal late enhancement was confirmed on both CCT and CMR for 4 patients. Myocardial extracellular volume (ECV) values measured by CCT and CMR were elevated in all patients, suggesting the presence of diffuse myocardial damage. The study findings indicated that CCT could provide adequate information about late myocardial enhancement and ECV quantification, indicating the effective evaluation of CTRCD by CCT.

Funding Acknowledgements Type of funding sources: Public hospital(s). Main funding source(s): The research fund of the Heart Center, Rigshospitalet, Denmark Background Assessment of left ventricular (LV) volumes and function is crucial in managing patients. New imaging modalities are becoming more common. It is therefore important to compare them with the standard echocardiographic method that most treatments rely on and to determine if they are suitable for all LV geometries. Purpose The purpose was to compare end-diastolic volume (EDV), end-systolic volume (ESV) and LV ejection fraction (LVEF) for the three most common imaging modalities; echocardiography, cardiac magnetic resonance (CMR) and cardiac computed tomography (CCT). Methods We included 85 subjects with various LV geometries; no cardiac disease (n = 44) and various cardiac disorders (n = 41). Cardiac assessment was performed using echocardiography followed immediately by CMR; re-examination after median 6 days, interquartile range 3-18 days using echocardiography followed immediately by CCT. We compared EDV, ESV and LVEF by three-dimensional echocardiography (echo-3D), CMR and CCT to echocardiographic biplane method of discs (echo-BP). The population was divided in four LV geometry profiles (normal, dilatation, hypertrophy, dilatation and hypertrophy) according to gender, age and indexed CMR-values of EDV and LV mass. We calculated inter-modality-ratios by dividing the values from echo-3D, CMR and CCT with echo-BP, to evaluate variances between the LV geometries. Results The figure demonstrates the agreement to echo-BP divided by geometry. Echo-3D had overall best agreement to EDV, ESV and LVEF. CMR overestimated both EDV and ESV. CCT overestimated EDV but not ESV. CCT overestimated LVEF by 4-16% in absolute values, whereas CMR and echo-3D had better agreement for LVEF. The correlation between echo-BP and echo-3D, CMR, and CCT, respectively was; EDV 0.91, 0.94, 0.90, ESV 0.86, 0.86, 0.79, and LVEF 0.40, 0.46, 0.38, all p &amp;lt; 0.001. CMR especially overestimated EDV and ESV in "hypertrophy and dilatation" whereas CCT especially underestimated EDV and ESV in solely "hypertrophy", with larger overestimation of LVEF. ANOVA-analysis of inter-modality-ratios between LV geometries indicated significant variation for EDV but not ESV by echo-3D (F = 2.9, p &amp;lt; 0.05 and F = 1.6, NS), no significant variation for EDV or ESV by CMR (F = 0.01 and 2.4, both NS), and significant variation for both EDV and ESV by CCT (F = 5.4, p &amp;lt; 0.01 and 7.2, p &amp;lt; 0.001). No significant variation for LVEF by echo-3D (F = 1.0, NS), but significant variation for CMR and CCT (CMR: F = 4.5, p &amp;lt; 0.01 and CCT: F = 8.6, p &amp;lt; 0.001) with slightly higher variation for CCT. Conclusions Echo-3D had the overall best agreement of volumes and LVEF, compared to echo-BP as a reference. CMR overestimated EDV and ESV whereas CCT overestimated EDV but not ESV, resulting in overestimation of LVEF by CCT but not CMR. In hypertrophic non-dilated LVs; CCT underestimated both EDV and especially ESV, with larger overestimation of LVEF. In general, CMR appears to be less dependent on LV geometry compared to echo-3D and CCT. Abstract Figure.

Coronary artery disease (CAD) is a leading cause of mortality and morbidity in most developed countries [1]. CAD is a common and sometimes disabling disorder, although medication therapy, percutaneous coronary intervention and coronary artery bypass grafting have developed recently. Medical doctors need to prevent from developing acute coronary syndrome. The development of non-invasive cardiac imaging tools (particularly, cardiac computed tomography, echocardiography and so on) for the diagnostic and prognostic assessments of patients is evolving evidence for various treatment strategies. Cardiac catheterization is golden standard for the diagnosis of CAD. Although the risk of adverse events for invasive coronary angiography is generally considered to be low, potential life-threatening complications can arise, including not only coronary artery dissection, but also arrhythmia, stroke, hemorrhage, myocardial infarction (MI), and death [2]. Non-invasive imaging devices for CAD have been developing, such as echocardiography, scintigraphy, computed tomography (CT) and magnetic resonance imaging (MRI) and so on. Particularly, the development of cardiac CT is remarkable in the last 10 years. Prior report suggested a hierarchial model of efficacy to assess the contribution of diagnostic imaging to the patient management process. Level 1 is technical quality of the images. Level 2 is diagnostic accuracy, sensitivity, and specificity associated with interpretation of the images. Level 3 is whether the information produces change in the referring physician’s diagnostic thinking. Level 4 is efficacy, which concerns effect on the patient management plan. Level 5 is effect of the information on patient outcomes. Level 6 is societal costs and benefits of a diagnostic imaging technology [3]. CT imaging was introduced in 1972 [4]. The ability to obtain cross-sectional images of the computer-assisted tomography, Sir Geoffrey N. Hounsfield and Allan M. Cormack were awarded the Nobel prize in Medicine in 1979. Since a 4 detector row cardiac CT angiography was launched in 1998. Cardiac CT has experienced rapid improvement of imaging qualities with the ongoing evolution of cardiac CT. The diagnostic accuracy of the 64 detector cardiac CT to detect coronary stenoses is available. Cardiac CT is useful for the diagnosis and risk stratification of CAD. Cardiac CT presently has not been considered a routine replacement for invasive coronary angiography,

Myocardial fat is often seen at cardiac computed tomography (CT) and magnetic resonance (MR) imaging of healthy adults and patients with myocardial diseases. Physiologic myocardial fat develops with aging and is commonly seen at CT in the anterolateral right ventricular (RV) free wall and RV outflow tract with normal or thickened RV myocardium and a normal-sized RV in elderly patients. Pathologic conditions with myocardial fat include healed myocardial infarction (MI); arrhythmogenic RV cardiomyopathy or dysplasia (ARVC); and others, such as cardiac lipoma, lipomatous hypertrophy of the interatrial septum, tuberous sclerosis complex, dilated cardiomyopathy, and cardiomyopathy with muscular dystrophy. In patients with healed MI, CT and MR imaging show fat in left ventricular myocardium that is of normal thickness or thin and follows the distribution of the coronary artery; CT often depicts fat in mostly subendocardial regions. In patients with ARVC, characteristic CT and MR imaging findings include a thin RV outflow tract and free wall caused by subepicardial fatty infiltration; fat in the RV moderator band, trabeculae, and ventricular septum; and RV enlargement and wall motion abnormality. Recognition of patient age, characteristic locations of myocardial fat, myocardial thickness, and ventricular size helps in differentiating physiologic and pathologic myocardial fat at cardiac imaging; findings of wall motion abnormality and late gadolinium enhancement at MR imaging help narrow the diagnosis.

Introduction Extra-cellular volume (ECV) fraction on magnetic resonance imaging (MRI) can evaluate the degree of myocardial fibrosis and has been reported to help diagnose and evaluate the prognosis of cardiomyopathy. In hypertrophic cardiomyopathy (HCM), ECV analysis on MRI is reported to help predict ventricular arrhythmias. However, the performance of cardiac MRI takes time, and there are also several contraindications. Cardiac computed tomography (CT) is more versatile than cardiac MRI and is also useful in screening coronary artery disease. ECV analysis on CT is now available, and a good correlation with ECV on MRI has been reported. We hypothesized that ECV on CT, a new fibrosis indicator, would be useful in predicting prognosis in HCM patients. Purpose To determine the utility of ECV analysis on CT to predict the prognosis in patients with HCM. Methods One hundred and three HCM patients (68 males, 66 ± 11 years old) who underwent cardiac CT using 320-row detector CT or 256-row detector CT, from 2008 to 2021 at our two hospitals were analyzed. We measured left ventricular (LV) ECV (LV-ECV) on CT and collected patient characteristics, transthoracic echocardiographic, and other CT findings. We investigated the relationship between these findings and the major adverse cardiac events (MACEs) (cardiac death, fatal arrhythmia, and heart failure hospitalization) after CT. Results All patients were followed for 64 ± 54 months after cardiac CT, and 15 patients (14.6%) had MACEs (ten heart failure hospitalization cases, two ventricular fibrillation cases, two sustained ventricular tachycardia cases, and one sudden cardiac death case). The patients with MACEs had a significantly higher LV-ECV, sudden cardiac death (SCD) risk score and lower LV ejection fraction (LVEF) than those without MACEs（42.0 ± 8.3% vs. 33.7 ± 6.1%, P &amp;lt; 0.001, 2.4 ± 0.39 vs 1.95 ± 0.16, P= 0.047, and 57.7 ± 11.9% vs. 66.7 ± 6.9%, P = 0.004). The percentage of dilated phase HCM was significantly higher in the patients with MACEs than those without MACEs (21% vs 0%, p=0.002). LV-ECV was the only significant predictor of MACEs based on the multivariate analysis by Cox proportional hazard model (hazard ratio 1.23, 95% confidence interval 1.09-1.41, P&amp;lt;0.001). The optimal threshold of LV-ECV to predict MACEs was 37.6% based on the receiver operating characteristic analysis. The sensitivity and specificity of LV-ECV to predict MACEs were 73% and 78% at the best cut-off, and the area under the curve was 0.79 (Figure A). The patients with LV-ECV ≥ 37.6% (30 patients) had significantly higher MACEs than those with LV-ECV &amp;lt; 37.6% during the follow-up periods (P &amp;lt; 0.001) (Figure B). Conclusion LV-ECV on CT of 37.6% is a good prognostic indicator in HCM cases. ECV analysis on CT helped predict MACEs in HCM cases.

The purpose of quantitative evaluation of cardiac images is to acquire more objective, accurate, and delicate numeric data than from the results of qualitative observation. By quantitative analysis, the prediction of cardiovascular risk and the depiction of subtle changes have become more reliable. Until cardiac computed tomography (CT) and magnetic resonance imaging (MRI) were introduced 10 years ago, echocardiography had been traditionally used for cardiac morphology imaging. Based on technical advancements, cardiovascular CT and MRI started to be used for quantitative evaluation of cardiovascular structures. In this article, quantitative evaluation techniques in cardiovascular imaging will be discussed with an emphasis on CT and MRI. Keywords: Cardiac CT, cardiac MRI, coronary calcium score, myocardial blood flow volume, plaque characterization, signal intensity mapping, ventricular function, wall shear stress.

A 67-year-old woman who had previous history of hypertension and hyperlipidemia was referred to the cardiologist because of nonspecific electrocardiographic abnormalities. During physical exam a systolic murmur was detected. Transthoracic echocardiography (TTE) showed aortic valve sclerosis with no evidence of valvular stenosis. An unexpected finding was the presence of a membrane at left atrium (LA) and a transesophageal echocardiography (TEE) was recommended with suspicion of cor triatriatum. No signs of obstruction to LA flow were demonstrable with pulsed-wave or colour Doppler analysis. On 3D TEE imaging, a structure compatible with a left atrial tendon was visualized. To complete the study computed tomography (CT) was performed, revealing the presence of a real membrane dividing the LA into two components, separating the pulmonary veins from the true LA chamber with the left atrial appendage (LAA), being the patient diagnosed of cor triatriatum. Cor triatriatum sinister (CTS) is a rare but well-recognised form of congenital heart disease. It is believed to reflect failure of incorporation of the common pulmonary vein into the LA. Defining the relationship between the CTS membrane and the LAA allows differentiation from a supra­mitral ring. In CTS, the membrane is located superior to the LAA (between the LAA and pulmonary veins), while a supra­mitral ring is located inferior to the LAA and is often adher­ent to, and constitutes part of, the mitral valve leaflets. The diagnosis of CTS may be made at any age. Most cases involve a nonobstructive membrane, diagnosis of which is facilitated by advances in imaging technology. TTE is adequate to define the clinical relevance of CTS but it may be more precisely tailored with cardiac CT or cardiac magnetic resonance (CMR) imaging. This case emphasizes the importance of a multimodality imaging approach. CTS can present as an isolated lesion, but it is more commonly seen in association with other congenital cardiac anomalies (patent foramen ovale, atrial septal defect, patent ductus arterio­sus, coarctation of the aorta, persistent left superior vena cava, ventricular septal defect, anomalous pulmonary venous drainage, and a variety of left-sided cardiac abnormalities). Nonobstructive asymptomatic adults do not require intervention. However, onset of any cardiovascular symptom should prompt detailed evaluation. A turbulent jet arising from the opening in an obstructive CTS membrane may produce jet lesions on the structurally normal mitral valve causing damage and secondary mitral regurgitation. Surgi­cal resection is the first line of management for an obstructive membrane in the LA. The development of atrial fibrillation in an individual with nonobstructive CTS may also constitute an indication for surgi­cal resection as the presence of the membrane may increase the risk of thromboembolic events. Abstract P1335 Figure. Cor triatriatum sinister (TTE,3D-TEE,CT)

Tricuspid annular plane systolic excursion for the evaluation of right ventricular function in functional cardiac CT compared to MRI

to evaluate the diagnostic accuracy of late iodine enhancement (LIE) in cardiac computed tomography (CCT) compared to late gadolinium enhancement (LGE) in cardiac magnetic resonance (CMR) for myocardial tissue characterization. EMBASE, PubMed/MEDLINE, and CENTRAL were searched for studies reporting the accuracy of LIE with LGE as the gold standard of reference. QUADAS-2 tool was used to assess the risk of bias. A bivariate random-effects model was used to analyze, pool, and plot the diagnostic performance measurements across studies. Pooled sensitivity, specificity, positive (+LR) and negative (-LR) likelihood ratio, diagnostic odds ratio (DOR), and hierarchical summary ROC curve (HSROC) were computed. Prospero registration number: CRD42023484045. Fourteen studies involving 526 patients and 5758 myocardial segments were included. At the patient level, LIE in CCT showed a pooled sensitivity of 0.96 (95% CI: 0.88-0.99), specificity of 0.95 (95% CI: 0.88-0.98) and the HSROC AUC of 0.98 (95% CI: 0.97-0.99). The +LR was 20.97 (95% CI: 7.54-58.38) and the -LR was 0.04 (95% CI: 0.01-0.13), resulting in a DOR of 535 (95% CI: 94-3024). At the segment level, sensitivity was 0.86 (95% CI: 0.79-0.91), specificity was 0.98 (95% CI: 0.96-0.99), and the HSROC AUC was 0.97 (95% CI:0.95-0.98). The +LR was 55.08 (95% CI: 19.94-152.16) and the -LR was 0.14 (95% CI: 0.09-0.22) with a DOR of 388 (95% CI: 113-1333). Dual-energy CCT improved segment-level sensitivity to 0.93 (95% CI: 0.88-0.96). LIE in CCT shows excellent diagnostic accuracy when compared to LGE in CMR for myocardial tissue characterization, suggesting its potential as a promising alternative to CMR. Question How does myocardial tissue characterization by late iodine enhancement (LIE) on cardiac CT (CCT) compare to late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR)? Findings LIE in CCT demonstrates excellent diagnostic accuracy, with high sensitivity and specificity at both patient and segment levels, using LGE in CMR as the reference. Clinical relevance LIE in CCT provides a reliable alternative to LGE in CMR, especially for patients for whom CMR is not available or feasible or is contraindicated, thus improving access to myocardial tissue characterization.

The authors sought to compare magnetic resonance imaging (MRI) and computed tomography (CT) for assessing left ventricular (LV) function parameters in a large patient population. The study was conducted on 181 patients who underwent cardiac MRI and cardiac CT for various indications. For MRI, we used two-dimensional cine balanced steady-state free precession (b-SSFP) sequences, and for CT we used multiphase short-axis reconstructions. Volume data sets were evaluated with dedicated software. Results were compared with a paired, two-tailed Student's t test, Pearson's correlation (r), and Bland-Altman analysis. A high level of concordance was observed between cardiac MRI and CT. Ejection fraction (EF) was 53+/-14% for MRI vs. 53%+/-15% for CT. There was good correlation for EF (r=0.71; p>0.05) and end-systolic volume (r=0.74; p>0.05). End-diastolic volume (74+/-23 ml at MRI vs. 71+/-19 ml at CT; r=0.58; p<0.05) and myocardial mass (63+/-20 g at MRI and 56+/-18 g at CT; r=0.89; p<0.01) showed statistically significant differences, although the discrepancy had no clinical impact. MRI and CT show a good level of agreement in assessing LV function parameters, and both can be used interchangeably in clinical practice.

Myocardial infarction (MI) is a leading cause of morbidity and mortality worldwide. Although rapid diagnosis and reperfusion in the acute setting rely primarily on clinical assessment, electrocardiography, echocardiography, and invasive coronary angiography, advanced cardiac imaging plays an essential role beyond the hyperacute phase. Cardiac computed tomography (CCT) and cardiac magnetic resonance (CMR) imaging provide complementary information that extends from coronary anatomy to myocardial tissue characterization and functional assessment. CMR imaging enables the comprehensive, multiparametric evaluation of MI, including left ventricular function, myocardial edema and area at risk, infarct size and transmural extent, microvascular obstruction, intramyocardial hemorrhage, myocardial viability, and ischemia using cine imaging, T1/T2 and T2* mapping, perfusion imaging, and late gadolinium enhancement. These features support an accurate differentiation between acute and chronic infarction, an assessment of myocardial salvage, and prognostic stratification. CCT offers a rapid, non-invasive assessment of coronary artery stenosis and plaque characteristics and has expanded to include an evaluation of ventricular function, myocardial perfusion, and delayed-enhancement patterns. When combined with CT-derived fractional flow reserve or myocardial perfusion imaging, CT allows for an integrated anatomic and functional assessment of the myocardium, particularly for non-culprit lesions, following MI. Myocardial delayed-enhancement CT can visualize the infarcted myocardium and microvascular injury in select patients, though it remains complementary to magnetic resonance imaging. This pictorial essay illustrates the imaging spectrum of MI and its major mechanical and thromboembolic complications, including ventricular rupture, septal defects, papillary muscle rupture, aneurysm formation, left ventricular thrombi, and pericardial disease. By highlighting the strengths and limitations of CCT and CMR and providing practical guidance for modality selection, this article aims to support informed clinical decision-making in the contemporary management of patients with MI.