Diagnostic accuracy of multidetector computed tomography coronary angiography in patients with dilated cardiomyopathy

2023 AHA/ACC/ACCP/ASPC/NLA/PCNA Guideline for the Management of Patients With Chronic Coronary Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2023 AHA/ACC/ACCP/ASPC/NLA/PCNA Guideline for the Management of Patients With Chronic Coronary Disease" provides an update to and consolidates new evidence since the "2012 ACCF/AHA/ACP/AATS/PCNA/SCAI/STS Guideline for the Diagnosis and Management of Patients With Stable Ischemic Heart Disease" and the corresponding "2014 ACC/AHA/AATS/PCNA/SCAI/STS Focused Update of the Guideline for the Diagnosis and Management of Patients With Stable Ischemic Heart Disease."

METHODS

A comprehensive literature search was conducted from September 2021 to May 2022. Clinical studies, systematic reviews and meta-analyses, and other evidence conducted on human participants were identified that were published in English from MEDLINE (through PubMed), EMBASE, the Cochrane Library, Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline.

STRUCTURE

This guideline provides an evidenced-based and patient-centered approach to management of patients with chronic coronary disease, considering social determinants of health and incorporating the principles of shared decision-making and team-based care. Relevant topics include general approaches to treatment decisions, guideline-directed management and therapy to reduce symptoms and future cardiovascular events, decision-making pertaining to revascularization in patients with chronic coronary disease, recommendations for management in special populations, patient follow-up and monitoring, evidence gaps, and areas in need of future research. Where applicable, and based on availability of cost-effectiveness data, cost-value recommendations are also provided for clinicians. Many recommendations from previously published guidelines have been updated with new evidence, and new recommendations have been created when supported by published data.

2023 AHA/ACC/ACCP/ASPC/NLA/PCNA Guideline for the Management of Patients With Chronic Coronary Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2023 AHA/ACC/ACCP/ASPC/NLA/PCNA Guideline for the Management of Patients With Chronic Coronary Disease" provides an update to and consolidates new evidence since the "2012 ACCF/AHA/ACP/AATS/PCNA/SCAI/STS Guideline for the Diagnosis and Management of Patients With Stable Ischemic Heart Disease" and the corresponding "2014 ACC/AHA/AATS/PCNA/SCAI/STS Focused Update of the Guideline for the Diagnosis and Management of Patients With Stable Ischemic Heart Disease."

METHODS

A comprehensive literature search was conducted from September 2021 to May 2022. Clinical studies, systematic reviews and meta-analyses, and other evidence conducted on human participants were identified that were published in English from MEDLINE (through PubMed), EMBASE, the Cochrane Library, Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline.

STRUCTURE

This guideline provides an evidenced-based and patient-centered approach to management of patients with chronic coronary disease, considering social determinants of health and incorporating the principles of shared decision-making and team-based care. Relevant topics include general approaches to treatment decisions, guideline-directed management and therapy to reduce symptoms and future cardiovascular events, decision-making pertaining to revascularization in patients with chronic coronary disease, recommendations for management in special populations, patient follow-up and monitoring, evidence gaps, and areas in need of future research. Where applicable, and based on availability of cost-effectiveness data, cost-value recommendations are also provided for clinicians. Many recommendations from previously published guidelines have been updated with new evidence, and new recommendations have been created when supported by published data.

Comprehensive Evaluation of Left Ventricle Dysfunction by a New Computed Tomography Scanner: The E-PLURIBUS Study

BACKGROUND

Although cardiac magnetic resonance (CMR) is considered the gold standard for myocardial fibrosis detection, cardiac computed tomography (CCT) is emerging as a promising alternative.

OBJECTIVES

The purpose of this study was to assess feasibility and diagnostic accuracy of a comprehensive functional and anatomical evaluation with CCT as compared with CMR in patients with newly diagnosed left ventricular dysfunction (LVD).

METHODS

A total of 128 consecutive patients with newly diagnosed LVD were screened. Based on the exclusion criteria, 28 cases were excluded. CCT was performed within 10 days from CMR. Biventricular volumes and ejection fraction, and presence and pattern of delayed enhancement (DE), were determined, along with evaluation of coronary arteries among patients undergoing invasive angiography in the 6 months after CCT.

RESULTS

Six cases were excluded because of claustrophobia at CMR. Among the 94 patients who formed the study population, the concordance between CCT and CMR in suggesting the cause of the LVD was high (94.7%, 89/94 patients) in the overall population and was 100% for identifying ischemic cardiomyopathy. The CCT diagnostic rate for DE assessment was also high (96.7%, 1,544/1,598 territories) and similar to that of CMR (97.4%; P = 0.345, CCT vs CMR). Moreover, CCT showed high diagnostic accuracy in the detection of DE (94.8%, 95% CI: 93.6%-95.8%) in a territory-based analysis. Biventricular volumes and function parameters as measured by CCT and CMR were similar, without significant differences with the exception of a modest difference in RV volume. CCT was confirmed to be accurate for assessing arterial coronary circulation. The mean radiation exposure of the whole CCT was 7.78 ± 2.53 mSv (0.84 ± 0.24 mSv for DE).

CONCLUSIONS

CCT performed with low-dose whole-heart coverage scanner and high-concentration contrast agent appears an effective noninvasive tool for a comprehensive assessment of patients with newly diagnosed LVD.

The Role of Cardiac Computed Tomography in Heart Failure

PURPOSE OF REVIEW

Cardiac computed tomography (CT) is becoming a more widely applied tool in the diagnosis and management of a variety of cardiovascular conditions, including heart failure. The aim of this narrative review is to examine the role of cardiac CT in patients with heart failure.

RECENT FINDINGS

Coronary computed tomographic angiography has robust diagnostic accuracy for ruling out coronary artery disease. These data are reflected in updated guidelines from major cardiology organizations. New roles for cardiac CT in myocardial imaging, perfusion scanning, and periprocedural planning, execution, and monitoring are being implemented. Cardiac CT is useful in ruling out coronary artery disease its diagnostic accuracy, accessibility, and safety. It is also intricately linked to invasive cardiac procedures that patients with heart failure routinely undergo.

Novel Cardiac Computed Tomography Methods for the Assessment of Anthracycline Induced Cardiotoxicity

Anthracyclines are among the most frequently utilized anti-cancer therapies; however, their use is frequently associated with off-target cardiotoxic effects. Cardiac computed tomography (CCT) is a validated and rapidly evolving technology for the evaluation of cardiac structures, coronary anatomy and plaque, cardiac function and preprocedural planning. However, with emerging new techniques, CCT is rapidly evolving to offer information beyond the evaluation of cardiac structure and epicardial coronary arteries to provide details on myocardial deformation, extracellular volume, and coronary vasoreactivity. The potential for molecular imaging in CCT is also growing. In the current manuscript we review these emerging computed tomography techniques and their potential role in the evaluation of anthracycline-induced cardiotoxicity.

Coronary plaque features on CTA can identify patients at increased risk of cardiovascular events

PURPOSE OF REVIEW

Multicenter studies showed that the characterization of coronary atherosclerosis by coronary computed tomography (CT) angiography (CCTA) provides independent and incremental prognostic value above and beyond traditional measures of coronary artery disease (CAD) and is able to identify patients at risk of future event. Aim of the present review is to expound the major imaging plaque features associated with increased risk of coronary event and to review the data supporting the usefulness of CCTA as tool for plaque assessment and for monitoring the changes in atherosclerotic burden.

RECENT FINDINGS

The evaluation of coronary atherosclerosis, including the measurement of imaging risk scores (e.g. CT-adapted Leaman score) was demonstrated as independent long-term predictor of acute coronary events. In particular, qualitative (remodelling index, low-attenuation plaque, napkin-ring sign, small spotty calcifications) and quantitative (plaque burden, total-, noncalcific- and fibrofatty plaque volume) plaque features were associated with increased risk. CCTA was also demonstrated to accurately quantify plaque volume vs. intravascular ultrasound and findings from PARADIGM and EVAPORATE studies supported the use of CCTA as noninvasive tool to follow the effect of medication on plaque progression/regression. Finally, interesting relationship between plaque features, coronary physiology and biomarkers have been described.

SUMMARY

Latest guidelines on the management of patients with stable CAD recommended CCTA in Class I of evidence, particularly when 'information on atherosclerosis are desired', underlining the usefulness of CCTA to characterize and quantify the atherosclerotic burden.

The Potential Role of Cardiac CT in the Evaluation of Patients With Known or Suspected Cardiomyopathy: From Traditional Indications to Novel Clinical Applications

After 15 years from its advent in the clinical field, coronary computed tomography (CCTA) is now widely considered as the best first-step test in patients with low-to-moderate pre-test probability of coronary artery disease. Technological innovation was of pivotal importance for the extensive clinical and scientific interest in CCTA. Recently, the advent of last generation wide-coverage CT scans paved the way for new clinical applications of this technique beyond coronary arteries anatomy evaluation. More precisely, both biventricular volume and systolic function quantification and myocardial fibrosis identification appeared to be feasible with last generation CT. In the present review we would focus on potential applications of cardiac computed tomography (CCT), beyond CCTA, for a comprehensive assessment patients with newly diagnosed cardiomyopathy, from technical requirements to novel clinical applications.

ACR Appropriateness Criteria® Nonischemic Myocardial Disease with Clinical Manifestations (Ischemic Cardiomyopathy Already Excluded)

Nonischemic cardiomyopathies encompass a broad spectrum of myocardial disorders with mechanical or electrical dysfunction without evidence of ischemia. There are five broad variants of nonischemic cardiomyopathies; hypertrophic cardiomyopathy (Variant 1), restrictive or infiltrative cardiomyopathy (Variant 2), dilated or unclassified cardiomyopathy (Variant 3), arrhythmogenic cardiomyopathy (Variant 4), and inflammatory cardiomyopathy (Variant 5). For variants 1, 3, and 4, resting transthoracic echocardiography, MRI heart function and morphology without and with contrast, and MRI heart function and morphology without contrast are the usually appropriate imaging modalities. For variants 2 and 5, resting transthoracic echocardiography and MRI heart function and morphology without and with contrast are the usually appropriate imaging modalities. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

MAGGIC Risk Model Predicts Adverse Events and Left Ventricular Remodeling in Non-Ischemic Dilated Cardiomyopathy

Purpose

We aimed to study the Meta-analysis Global Group in Chronic Heart Failure (MAGGIC) risk model’s prognostic value and relationship with left ventricular remodeling in dilated cardiomyopathy.

Patients and Methods

Dilated cardiomyopathy patients were prospectively recruited and underwent clinical assessments. MAGGIC risk score was calculated. Patients were followed up for adverse events and echocardiography. Primary endpoints were all-cause mortality and first rehospitalization due to heart failure. Secondary endpoint was left ventricular remodeling defined as a decline in left ventricular ejection fraction >10% or an increase in left ventricular end-diastolic diameter >10%. Survival status was examined using Cox regression analysis. The model’s ability to discriminate adverse events and left ventricular remodeling was calculated using a receiver operating characteristics curve.

Results

In total, 114 patients were included (median follow-up time = 31 months). The risk score was independently related to adverse events (2-year all-cause mortality: hazard ratio [HR] = 1.122; 95% confidence interval [CI], 1.043–1.208; 1-year first rehospitalization due to heart failure: HR = 1.094; 95% CI, 1.032–1.158; 2-year first rehospitalization due to heart failure: HR = 1.088; 95% CI, 1.033–1.147, all P < 0.05). One-year change in left ventricular end-diastolic diameter was correlated with the risk score (r = 0.305, P = 0.002). The model demonstrated modest ability in discriminating adverse events and left ventricular remodeling (all areas under the curve were 0.6–0.7).

Conclusion

The MAGGIC risk score was related to adverse events and left ventricular remodeling in dilated cardiomyopathy.

Multi-Modality Imaging in Dilated Cardiomyopathy: With a Focus on the Role of Cardiac Magnetic Resonance

Heart failure (HF) is recognized as a leading cause of morbidity and mortality worldwide. Dilated cardiomyopathy (DCM) is a common phenotype in patients presenting with HF. Timely diagnosis, appropriate identification of the underlying cause, individualized risk stratification, and prediction of clinical response to treatment have improved the prognosis of DCM over the last few decades. In this article, we reviewed the current evidence on available imaging techniques used for DCM patients. In this direction, we evaluated appropriate scenarios for the implementation of echocardiography, nuclear imaging, and cardiac computed tomography, and we focused on the primordial role that cardiac magnetic resonance (CMR) holds in the diagnosis, prognosis, and tailoring of therapeutic options in this population of special clinical interest. We explored the predictive value of CMR toward left ventricular reverse remodeling and prediction of sudden cardiac death, thus guiding the decisions for device therapy. Principles underpinning the use of state-of-the-art CMR techniques such as parametric mapping and feature-tracking strain analysis are also provided, along with expectations for the anticipated future advances in this field. We also attempted to correlate the evidence with clinical practice, with the intent to address questions on selecting the optimal imaging method for different indications and clinical needs. Overall, we recommend a comprehensive assessment of DCM patients at baseline and at follow-up intervals depending on the clinical status, with the addition of CMR as a second-line modality to other imaging techniques. We also provide an algorithm to guide the detailed imaging approach of the patient with DCM. We expect that future guidelines will upgrade their clinical recommendations for the utilization of CMR in DCM, which is expected to further improve the quality of care and the outcomes. This review provides an up-to-date perspective on the imaging of dilated cardiomyopathy patients and will be of clinical value to training doctors and physicians involved in the area of heart failure.

Computed Tomographic Angiography Assessment of Epicardial Coronary Vasoreactivity for Early Detection of Doxorubicin-Induced Cardiotoxicity

Background

The vascular endothelium is a novel target for the detection, management, and prevention of doxorubicin (DOX)-induced cardiotoxicity.

Objectives

The study aimed to: 1) develop a methodology by computed tomography angiography (CTA) to evaluate stress-induced changes in epicardial coronary diameter; and 2) apply this to a chronic canine model of DOX-induced cardiotoxicity to assess vascular toxicity.

Methods

To develop and validate quantitative methods, sequential retrospectively gated coronary CTAs were performed in 16 canines. Coronary diameters were measured at prespecified distances during rest, adenosine (ADE) (280 μg/kg/min), rest 30 min post-ADE, and dobutamine (DOB) (5 μg/kg/min). A subgroup of 8 canines received weekly intravenous DOX (1 mg/kg) for 12 to 15 weeks, followed by rest-stress CTA at cumulative doses of ∼4-mg/kg (3 to 5 mg/kg), ∼8-mg/kg (7 to 9 mg/kg), and ∼12-mg/kg (12 to 15 mg/kg) of DOX. Echocardiograms were performed at these timepoints to assess left ventricular ejection fraction and global longitudinal strain.

Results

Under normal conditions, epicardial coronary arteries reproducibly dilated in response to ADE (left anterior descending coronary artery [LAD]: 12 ± 2%, left circumflex coronary artery [LCx]: 13 ± 2%, right coronary artery [RCA]: 14 ± 2%) and DOB (LAD: 17 ± 3%, LCx: 18 ± 2%, RCA: 15 ± 3%). With DOX, ADE vasodilator responses were impaired after ∼4-mg/kg (LAD: –3 ± 1%, LCx: 0 ± 2%, RCA: –5 ± 2%) and ∼8-mg/kg (LAD: –3 ± 1%, LCx: 0 ± 1%, RCA: –2 ± 2%). The DOB dilation response was preserved at ∼4-mg/kg of DOX (LAD: 18 ± 4%, LCx: 11 ± 3%, RCA: 11 ± 2%) but tended to decrease at ∼8-mg/kg of DOX (LAD: 4 ± 2%, LCx: 8 ± 3%, RCA: 3 ± 2%). A significant left ventricular ejection fraction reduction was observed only at 12 to 15 mg/kg DOX (baseline: 63 ± 2%, 12-mg/kg: 45 ± 3%). Global longitudinal strain was abnormal at ∼4-mg/kg of DOX (p = 0.011).

Conclusions

CTA can reliably assess epicardial coronary diameter in response to pharmacological stressors, providing a noninvasive functional index of coronary vasoreactivity. Impaired epicardial vasodilation occurs early in DOX-induced cardiotoxicity.

Myocardial Assessment with Cardiac CT: Ischemic Heart Disease and Beyond

PURPOSE OF REVIEW

The aim of this review is to highlight recent advancements, current trends, and the expanding role for cardiac CT (CCT) in the evaluation of ischemic heart disease, nonischemic cardiomyopathies, and some specific congenital myocardial disease states.

RECENT FINDINGS

CCT is a highly versatile imaging modality for the assessment of numerous cardiovascular disease states. Coronary CT angiography (CCTA) is now a well-established first-line imaging modality for the exclusion of significant coronary artery disease (CAD); however, CCTA has modest positive predictive value and specificity for diagnosing obstructive CAD in addition to limited capability to evaluate myocardial tissue characteristics.

SUMMARY

CTP, when combined with CCTA, presents the potential for full functional and anatomic assessment with a single modality. CCT is a useful adjunct in select patients to both TTE and CMR in the evaluation of ventricular volumes and systolic function. Newer applications, such as dynamic CTP and DECT, are promising diagnostic tools offering the possibility of more quantitative assessment of ischemia. The superior spatial resolution and volumetric acquisition of CCT has an important role in the diagnosis of other nonischemic causes of cardiomyopathies.

Computed tomography of cardiomyopathies

Cardiac computed tomography (CT) is increasingly used in the evaluation of cardiomyopathies, particularly in patients who are not able to undergo other non-invasive imaging tests such as magnetic resonance imaging (MRI) due to the presence of MRI-incompatible pacemakers/defibrillators or other contraindications or due to extensive artifacts from indwelling metallic devices. Advances in scanner technology enable acquisition of CT images with high spatial resolution, good temporal resolution, wide field of view and multi-planar reconstruction capabilities. CT is useful in cardiomyopathies in several ways, particularly in the evaluation of coronary arteries, characterization of cardiomyopathy phenotype, quantification of cardiac volumes and function, treatment-planning, and post-treatment evaluation. In this article, we review the imaging techniques and specific applications of CT in the evaluation of cardiomyopathies.

Korean Guidelines for Diagnosis and Management of Chronic Heart Failure

The prevalence of heart failure (HF) is skyrocketing worldwide, and is closely associated with serious morbidity and mortality. In particular, HF is one of the main causes for the hospitalization and mortality in elderly individuals. Korea also has these epidemiological problems, and HF is responsible for huge socioeconomic burden. However, there has been no clinical guideline for HF management in Korea. 
The present guideline provides the first set of practical guidelines for the management of HF in Korea and was developed using the guideline adaptation process while including as many data from Korean studies as possible. The scope of the present guideline includes the definition, diagnosis, and treatment of chronic HF with reduced/preserved ejection fraction of various etiologies.

High-pitch versus conventional cardiovascular CT in patients being assessed for transcatheter aortic valve implantation: a real-world appraisal

Objective

High-pitch protocols are increasingly used in cardiovascular CT assessment for transcatheter aortic valve implantation (TAVI), but the impact on diagnostic image quality is not known.

Methods

We reviewed 95 consecutive TAVI studies: 44 (46%) high-pitch and 51 (54%) standard-pitch. Single high-pitch scans were performed regardless of heart rate. For standard-pitch acquisitions, a separate CT-aortogram and CT-coronary angiogram were performed with prospective gating, unless heart rate was ≥70 beats/min, when retrospective gating was used. The aortic root and coronary arteries were assessed for artefact (significant artefact=1; artefact not limiting diagnosis=2; no artefact=3). Aortic scans were considered diagnostic if the score was >1; the coronaries, if all three epicardial arteries scored >1.

Results

There was no significant difference in diagnostic image quality for either the aorta (artefact-free high-pitch: 31 (73%) scans vs standard-pitch: 40 (79%), p=0.340) or the coronary tree as a whole (10 (23%) vs 15 (29%), p=0.493). However, proximal coronary arteries were less well visualised using high-pitch acquisitions (16 (36%) vs 30 (59%), p=0.04). The median (IQR) radiation dose was significantly lower in the high-pitch cohort (dose-length product: 347 (318–476) vs 1227 (1150–1474) mGy cm, respectively, p<0.001), and the protocol required almost half the amount of contrast.

Conclusions

The high-pitch protocol significantly reduces radiation and contrast doses and is non-inferior to standard-pitch acquisitions for aortic assessment. For aortic root assessment, the high-pitch protocol is recommended. However, if coronary assessment is critical, this should be followed by a conventional standard-pitch, low-dose, prospectively gated CT-coronary angiogram if the high-pitch scan is non-diagnostic.

Evaluation of computed tomography in patients with atypical angina or chest pain clinically referred for invasive coronary angiography: randomised controlled trial

OBJECTIVE

 To evaluate whether invasive coronary angiography or computed tomography (CT) should be performed in patients clinically referred for coronary angiography with an intermediate probability of coronary artery disease.

DESIGN

 Prospective randomised single centre trial.

SETTING

 University hospital in Germany.

PARTICIPANTS

 340 patients with suspected coronary artery disease and a clinical indication for coronary angiography on the basis of atypical angina or chest pain.

INTERVENTIONS

 168 patients were randomised to CT and 172 to coronary angiography. After randomisation one patient declined CT and 10 patients declined coronary angiography, leaving 167 patients (88 women) and 162 patients (78 women) for analysis. Allocation could not be blinded, but blinded independent investigators assessed outcomes.

MAIN OUTCOME MEASURE

 The primary outcome measure was major procedural complications within 48 hours of the last procedure related to CT or angiography.

RESULTS

 Cardiac CT reduced the need for coronary angiography from 100% to 14% (95% confidence interval 9% to 20%, P<0.001) and was associated with a significantly greater diagnostic yield from coronary angiography: 75% (53% to 90%) v 15% (10% to 22%), P<0.001. Major procedural complications were uncommon (0.3%) and similar across groups. Minor procedural complications were less common in the CT group than in the coronary angiography group: 3.6% (1% to 8%) v 10.5% (6% to 16%), P=0.014. CT shortened the median length of stay in the angiography group from 52.9 hours (interquartile range 49.5-76.4 hours) to 30.0 hours (3.5-77.3 hours, P<0.001). Overall median exposure to radiation was similar between the CT and angiography groups: 5.0 mSv (interquartile range 4.2-8.7 mSv) v 6.4 mSv (3.4-10.7 mSv), P=0.45. After a median follow-up of 3.3 years, major adverse cardiovascular events had occurred in seven of 167 patients in the CT group (4.2%) and six of 162 (3.7%) in the coronary angiography group (adjusted hazard ratio 0.90, 95% confidence interval 0.30 to 2.69, P=0.86). 79% of patients stated that they would prefer CT for subsequent testing. The study was conducted at a University hospital in Germany and thus the performance of CT may be different in routine clinical practice. The prevalence was lower than expected, resulting in an underpowered study for the predefined primary outcome.

CONCLUSIONS

 CT increased the diagnostic yield and was a safe gatekeeper for coronary angiography with no increase in long term events. The length of stay was shortened by 22.9 hours with CT, and patients preferred non-invasive testing.Trial registration ClinicalTrials.gov NCT00844220.

The role of angiographic follow-up after percutaneous coronary intervention

In the early days of coronary angioplasty, follow-up coronary angiography was often performed to assess restenosis. Angiographic restenosis has been shown to be associated with worse clinical outcomes, though the exact causality has yet to be determined. Numerous studies have repeatedly demonstrated that routine follow-up coronary angiography increases the incidence of target lesion revascularization without a clear reduction in mortality or myocardial infarction. Despite the lack of proven benefit of angiographic follow-up, routine follow-up coronary angiography is still being performed in certain countries and facilities. There are several factors that might explain the lack of benefit of angiographic follow-up: 1) lower incidence of stent failure in the current drug-eluting stent era has attenuated the net clinical benefit of follow-up angiography. 2) Angiographic restenosis might not lead to myocardial ischemia. 3) Patients that do have functionally significant restenosis are often referred for coronary angiography due to clinical indications such as intractable angina. 4) Absence of restenosis at the time of follow-up angiography does not exclude future restenosis. The absence of proven benefit in unselected populations does not necessarily preclude the presence of benefit in selected population, and there may be a subgroup of patients who can benefit from angiographic follow-up such as those with a large myocardial ischemic territory or those at very high risk of restenosis. Until there is more clinical evidence with respect to follow-up angiography, the decision of whether or not to perform it routinely in selected high-risk population should entail an in-depth discussion with the patient.

Novel Imaging Techniques for Heart Failure

Imaging techniques play a main role in heart failure (HF) diagnosis, assessment of aetiology and treatment guidance. Echocardiography is the method of choice for its availability, cost and it provides most of the information required for the management and follow up of HF patients. Other non-invasive cardiac imaging modalities, such as cardiovascular magnetic resonance (CMR), nuclear imaging-positron emission tomography (PET) and single-photon emission computed tomography (SPECT) and computed tomography (CT) could provide additional aetiological, prognostic and therapeutic information, especially in selected populations. This article reviews current indications and possible future applications of imaging modalities to improve the management of HF patients.

Imaging Techniques in Acute Heart Failure

In recent years, imaging techniques have revolutionized the diagnosis of heart failure. In patients with a clinical picture of acute decompensation, prognosis is largely determined by early implementation of general measures and treatment of the underlying cause. Given its diagnostic yield and portability, ultrasound has become an essential tool in the setting of acute heart failure, and is currently found in all medical departments involved in the care of the critically ill patient. Cardiac magnetic resonance and computed tomography allow detailed characterization of multiple aspects of cardiac structure and function that were previously unavailable. This helps guide and monitor many of the treatment decisions in the acute heart failure population in an entirely noninvasive way. This article aims to review the usefulness of the imaging techniques that are clinically relevant in the context of an episode of acute heart failure. We discuss the indications and limitations of these techniques in detail and describe the general principles for the appropriate interpretation of results.

Korean guidelines for the appropriate use of cardiac CT

The development of cardiac CT has provided a non-invasive alternative to echocardiography, exercise electrocardiogram, and invasive angiography and cardiac CT continues to develop at an exponential speed even now. The appropriate use of cardiac CT may lead to improvements in the medical performances of physicians and can reduce medical costs which eventually contribute to better public health. However, until now, there has been no guideline regarding the appropriate use of cardiac CT in Korea. We intend to provide guidelines for the appropriate use of cardiac CT in heart diseases based on scientific data. The purpose of this guideline is to assist clinicians and other health professionals in the use of cardiac CT for diagnosis and treatment of heart diseases, especially in patients at high risk or suspected of heart disease.

Functional relevance of coronary artery disease by cardiac magnetic resonance and cardiac computed tomography: myocardial perfusion and fractional flow reserve

Coronary artery disease (CAD) is one of the leading causes of morbidity and mortality and it is responsible for an increasing resource burden. The identification of patients at high risk for adverse events is crucial to select those who will receive the greatest benefit from revascularization. To this aim, several non-invasive functional imaging modalities are usually used as gatekeeper to invasive coronary angiography, but the diagnostic yield of elective invasive coronary angiography remains unfortunately low. Stress myocardial perfusion imaging by cardiac magnetic resonance (stress-CMR) has emerged as an accurate technique for diagnosis and prognostic stratification of the patients with known or suspected CAD thanks to high spatial and temporal resolution, absence of ionizing radiation, and the multiparametric value including the assessment of cardiac anatomy, function, and viability. On the other side, cardiac computed tomography (CCT) has emerged as unique technique providing coronary arteries anatomy and more recently, due to the introduction of stress-CCT and noninvasive fractional flow reserve (FFR-CT), functional relevance of CAD in a single shot scan. The current review evaluates the technical aspects and clinical experience of stress-CMR and CCT in the evaluation of functional relevance of CAD discussing the strength and weakness of each approach.

Diagnostic accuracy of multidetector computed tomography coronary angiography in 325 consecutive patients referred for transcatheter aortic valve replacement

BACKGROUND

Multidetector computed tomography (MDCT) provides detailed assessment of valve annulus and iliofemoral vessels in transcatheter aortic valve replacement (TAVR) patients. However, data on diagnostic performance of MDCT coronary angiography (MDCT-CA) are scarce. The aim of the study is to assess diagnostic performance of MDCT for coronary artery evaluation before TAVR.

METHODS

A total of 325 consecutive patients (234 without previous myocardial revascularization, 49 with previous coronary stenting, and 42 with previous coronary artery bypass graft [CABG]) underwent invasive coronary angiography and MDCT before TAVR. MDCT-CA was performed using the same data set dedicated to standard MDCT aortic annulus evaluation. Multidetector computed tomography-CA evaluability and diagnostic accuracy in comparison with invasive coronary angiography as criterion standard were assessed.

RESULTS

The MDCT-CA evaluability of native coronaries was 95.6%. The leading cause of unevaluability was beam-hardening artifact due to coronary calcifications. In a segment-based analysis, MDCT-CA showed sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for detecting ≥50% stenosis of 91%, 99.2%, 83.4%, 99.6% and 98.8%, respectively. The MDCT-CA evaluability of coronary stents was 82.1%. In a segment-based analysis, MDCT-CA showed sensitivity, specificity, PPV, NPV, and accuracy for detecting ≥50% in-stent restenosis of 94.1%, 86.7%, 66.7%, 98.1%, and 88.3%, respectively. All CABGs were correctly assessed by MDCT-CA. In a patient-based analysis, MDCT-CA showed sensitivity, specificity, PPV, NPV, and accuracy of 89.7%, 90.8%, 80.6%, 95.4%, and 90.5%, respectively.

CONCLUSIONS

Multidetector computed tomography-CA allows to correctly rule out the presence of significant native coronary artery stenosis, significant in-stent restenosis, and CABG disease in patients referred for TAVR.

Clinical use of multimodality imaging in the assessment of dilated cardiomyopathy

Learning objectives: =To understand the use of cardiovascular imaging for diagnosis, evaluation of prognosis and for supporting treatment decisions and monitoring therapy in patients with dilated cardiomyopathy by providing morphologic, functional and etiologic information, including refined assessment of ventricular function. =To provide to the clinical cardiologist the information on what to expect from each imaging modality and how to work together with the cardiovascular imaging expert to fully explore the potential of complementary imaging techniques. = To provide a look into the future role of new imaging modalities such as molecular imaging.

Assessment of the myocardium with cardiac computed tomography

The imaging of myocardial disease is of increasing importance for cardiologists from all subspecialties, for diagnosis, risk stratification, or to facilitate therapy. While the gold standard modalities for such assessment are cardiac magnetic resonance and echocardiography, these are not universally suitable. Cardiac computed tomography (CT), well-established for the assessment of coronary artery disease (CAD), can be of value in the assessment of myocardial pathology, due to excellent patient compatibility and tolerability, high spatial resolution, and acceptable tissue characterization. This review considers the value and limitations of CT in the assessment of the myocardial sequelae of CAD, and for patients with a variety of other cardiomyopathic diseases, depicts some of the common findings, and considers current developments in this area.

CT vs SPECT: CT is the first-line test for the diagnosis and prognosis of stable coronary artery disease

Non-invasive cardiac imaging is pivotal in the diagnosis and prognosis of patients with stable CAD. Nuclear SPECT, PET, stress echocardiography and more recently cardiac magnetic resonance imaging have been utilized with excellent diagnostic accuracy. However, along with their inherent individual limitations, most modalities detect ischemia but lack the ability to define coronary anatomy or evaluate for subclinical atherosclerosis. A modality that not only accurately diagnoses obstructive CAD and also facilitates early identification of non-obstructive CAD may be of interest because it may allow for earlier aggressive risk factor modification and primary prevention. Cardiac computerized tomographic angiography (CCTA) has the potential to accurately detect or exclude luminal stenosis, as well as identify and quantify subclinical atherosclerosis in the absence if luminal narrowing. However CCTA, being a relatively a new modality, has less supporting evidence when compared to more mature modalities such as SPECT. Therefore, the question that begs to be addressed is whether CCTA can be utilized as a first line test in establishing the diagnosis and prognosis of CAD.

Methodological quality of diagnostic accuracy studies on non-invasive coronary CT angiography: influence of QUADAS (Quality Assessment of Diagnostic Accuracy Studies included in systematic reviews) items on sensitivity and specificity

OBJECTIVES

To evaluate the methodological quality of diagnostic accuracy studies on coronary computed tomography (CT) angiography using the QUADAS (Quality Assessment of Diagnostic Accuracy Studies included in systematic reviews) tool.

METHODS

Each QUADAS item was individually defined to adapt it to the special requirements of studies on coronary CT angiography. Two independent investigators analysed 118 studies using 12 QUADAS items. Meta-regression and pooled analyses were performed to identify possible effects of methodological quality items on estimates of diagnostic accuracy.

RESULTS

The overall methodological quality of coronary CT studies was merely moderate. They fulfilled a median of 7.5 out of 12 items. Only 9 of the 118 studies fulfilled more than 75 % of possible QUADAS items. One QUADAS item ("Uninterpretable Results") showed a significant influence (P = 0.02) on estimates of diagnostic accuracy with "no fulfilment" increasing specificity from 86 to 90 %. Furthermore, pooled analysis revealed that each QUADAS item that is not fulfilled has the potential to change estimates of diagnostic accuracy.

CONCLUSIONS

The methodological quality of studies investigating the diagnostic accuracy of non-invasive coronary CT is only moderate and was found to affect the sensitivity and specificity. An improvement is highly desirable because good methodology is crucial for adequately assessing imaging technologies.

KEY POINTS

• Good methodological quality is a basic requirement in diagnostic accuracy studies. • Most coronary CT angiography studies have only been of moderate design quality. • Weak methodological quality will affect the sensitivity and specificity. • No improvement in methodological quality was observed over time. • Authors should consider the QUADAS checklist when undertaking accuracy studies.

Use of 3x2 tables with an intention to diagnose approach to assess clinical performance of diagnostic tests: meta-analytical evaluation of coronary CT angiography studies

OBJECTIVE

To determine whether a 3 × 2 table, using an intention to diagnose approach, is better than the "classic" 2 × 2 table at handling transparent reporting and non-evaluable results, when assessing the accuracy of a diagnostic test.

DESIGN

Based on a systematic search for diagnostic accuracy studies of coronary computed tomography (CT) angiography, full texts of relevant studies were evaluated to determine whether they could calculate an alternative 3 × 2 table. To quantify an overall effect, we pooled diagnostic accuracy values according to a meta-analytical approach.

DATA SOURCES

Medline (via PubMed), Embase (via Ovid), and ISI Web of Science electronic databases.

ELIGIBILITY CRITERIA

Prospective English or German language studies comparing coronary CT with conventional coronary angiography in all patients and providing sufficient data for a patient level analysis.

RESULTS

120 studies (10,287 patients) were eligible. Studies varied greatly in their approaches to handling non-evaluable findings. We found 26 studies (including 2298 patients) that allowed us to calculate both 2 × 2 tables and 3 × 2 tables. Using a bivariate random effects model, we compared the 2 × 2 table with the 3 × 2 table, and found significant differences for pooled sensitivity (98.2 (95% confidence interval 96.7 to 99.1) v 92.7 (88.5 to 95.3)), area under the curve (0.99 (0.98 to 1.00) v 0.93 (0.91 to 0.95)), positive likelihood ratio (9.1 (6.2 to 13.3) v 4.4 (3.3 to 6.0)), and negative likelihood ratio (0.02 (0.01 to 0.04) v 0.09 (0.06 to 0.15); (P<0.05)).

CONCLUSION

Parameters for diagnostic performance significantly decrease if non-evaluable results are included by a 3 × 2 table for analysis (intention to diagnose approach). This approach provides a more realistic picture of the clinical potential of diagnostic tests.

Dual source computed tomography coronary angiography in new onset cardiomyopathy

AIM: To evaluate safety and utility of coronary computed tomography angiography (CCTA) compared to invasive coronary angiography (ICA) in new cardiomyopathy.

METHODS: Eighteen patients (mean age 56.5 years, 10 males) who presented for evaluation of new onset heart failure with evidence of systolic dysfunction (ejection fraction < 40%) on echocardiography and recent ICA were prospectively enrolled. Patients with known coronary artery disease, atrial fibrillation, creatinine > 1.5 g/dL, and contraindication to intravenous contrast administration were excluded. CCTA was performed using a dual source 64-slice scanner. Mean heart rate was 75 beats per minute. Stenosis was graded for each coronary segment as: none, mild (< 50%), moderate (50%-70%), severe (> 70%), or non-evaluable. Ischemic cardiomyopathy (ICM) was diagnosed if severe stenosis was present in the left main, proximal left anterior descending artery, or two or more major arteries.

RESULTS: Two patients were diagnosed with ICM by ICA. CCTA correctly identified 2 patients with ICM and 16 patients as non-ICM. CCTA successfully evaluated 240/246 coronary segments with an accuracy of 97.5%, sensitivity 70%, specificity 98.7%, positive predictive value of 70%, and negative predictive value of 98.7% for identifying severe stenosis on a per-segment level.

CONCLUSION: Dual source 64-slice multi-detector CCTA is a safe, accurate, and non-invasive technique for diagnosing ICM in patients presenting during the acute phase of newly diagnosed cardiomyopathy.

Clinical indications for cardiac computed tomography. From the Working Group of the Cardiac Radiology Section of the Italian Society of Medical Radiology (SIRM)

Cardiac computed tomography (CCT) has grown as a useful means in different clinical contexts. Technological development has progressively extended the indications for CCT while reducing the required radiation dose. Even today there is little documentation from the main international scientific societies describing the proper use and clinical indications of CCT; in particular, there are no complete guidelines. This document reflects the position of the Working Group of the Cardiac Radiology Section of the Italian Society of Radiology concerning the indications for CCT.

Imaging the right heart: the use of integrated multimodality imaging

During recent years, right ventricular (RV) structure and function have been found to be an important determinant of outcome in different cardiovascular and also pulmonary diseases. Currently, echocardiography and cardiac magnetic resonance (CMR) imaging are the two imaging modalities most commonly used to visualize the RV. Most structural abnormalities of the RV can be reliably described by echocardiography but due its complex geometrical shape, echocardiographic assessment of RV function is more challenging. Newer promising echocardiographic techniques are emerging but lack of validation and limited normal reference data influence their routine clinical application. Cardiac magnetic resonance is generally considered the clinical reference technique due to its unlimited imaging planes, superior image resolution, and three-dimensional volumetric rendering. The accuracy and reliability of CMR measurements make it the ideal tool for serial examinations of RV function. Multidetector computed tomography (MDCT) plays an important role in the diagnosis of pulmonary emboli but can also be used for assessing RV ischaemic disease or as an alternative for CMR if contra-indicated. Radionuclide techniques have become more obsolete in the current era. The different imaging modalities should be considered complimentary and each plays a role for different indications.

Role of multimodality imaging in ischemic and non-ischemic cardiomyopathy

Chronic heart failure (CHF) is a major and growing problem in the western hemisphere, affecting about 5 million patients in the United States. In daily practice patients with left ventricular systolic dysfunction (LVSD) and significant angiographic coronary artery disease (CAD) are felt to have an ischemic cardiomyopathy (ICMP) and those without CAD or mild-moderate CAD out of proportion to the extent of LVSD are felt to have a non-ischemic cardiomyopathy (NICMP). Although invasive coronary angiography is the gold standard for the diagnosis of CAD, recent advances in non-invasive imaging have created multiple options for evaluating ICMP and NICMP. This review details the role of cardiac imaging in the diagnosis of ICMP and NICMP and outlines an algorithm of use of non-invasive tests in asymtomatic LVSD and symptomatic heart failure.

Radiation dose and diagnostic accuracy of multidetector computed tomography for the detection of significant coronary artery stenoses: a meta-analysis

We conducted a meta-analysis evaluating the critical ratio between effective radiation dose (ED), feasibility (Fe) and diagnostic accuracy (Ac) of multidetector computed tomography (MDCT) for the detection of significant coronary artery disease. By using our predetermined criteria, we selected human studies published in English in which the ED and raw data of Ac vs. invasive coronary angiography in a segment based model were specified. Data from 31 studies including 3661 patients (mean age 61.9 ± 4.5 years, heart rate 62.5 ± 6.7 bpm) and 50,236 coronary artery segments were analysed and are reported. Overall, Fe, sensitivity, specificity, negative predictive value, positive predictive value, Ac and ED were 95%, 90%, 96%, 99%, 69%, 95% and 10.4 ± 5.4 mSv, respectively. Multivariate analysis showed that prospective ECG-gating (-8.8 mSv CI95% -13.4 to -4.3 mSv, p=0.001), dual-source (-3.7 mSv CI95% -7.9 to 0 mSv, p=0.05) and BMI-adapted scanning protocols (-4.5 mSv CI95% -8.7 to -2.7 mSv, p=0.03) were independent predictors of ED reduction. In patients with low heart rate, the best compromise between ED, Fe and Ac (2.5 mSv, 97% and 98%, respectively) was obtained combining prospective ECG-gating and BMI-adapted scanning protocols, while in patients with high heart rate the strategy associated with the best results (10 mSv, 98% and 97%, respectively) was the use of dual-source MDCT with retrospective ECG gating and modulation dose. In conclusion, careful selection of CT scanning protocols according to the patient's characteristics is critical for keeping the radiation exposure "as low as reasonably achievable" (ALARA) without impairing Fe and Ac.