Photon-counting detector computed tomography in cardiac imaging.

Photon-counting detector computed tomography (PCD-CT) has emerged as a revolutionary technology in CT imaging. PCD-CT offers significant advancements over conventional energy-integrating detector CT, including increased spatial resolution, artefact reduction and inherent spectral imaging capabilities. In cardiac imaging, PCD-CT can offer a more accurate assessment of coronary artery disease, plaque characterisation and the in-stent lumen. Additionally, it might improve the visualisation of myocardial fibrosis through qualitative late enhancement imaging and quantitative extracellular volume measurements. The use of PCD-CT in cardiac imaging holds significant potential, positioning itself as a valuable modality that could serve as a one-stop-shop by integrating both angiography and tissue characterisation into a single examination. Despite its potential, large-scale clinical trials, standardisation of protocols and cost-effectiveness considerations are required for its broader integration into clinical practice. This narrative review provides an overview of the current literature on PCD-CT regarding the possibilities and limitations of cardiac imaging.

Clinical and echocardiographic parameters associated with outcomes in patients with moderate secondary mitral regurgitation.

BACKGROUND: Significant secondary mitral regurgitation (SMR) is known to be associated with worse prognosis. However, data focusing specifically on moderate SMR and associated risk factors are lacking. In the present study, clinical and echocardiographic parameters associated with outcomes were evaluated in a large cohort of patients with moderate SMR. METHODS: Patients with moderate SMR were retrospectively included and stratified by New York Heart Association (NYHA) class and specific aetiology (atrial SMR (aSMR) or ventricular SMR (vSMR)) with a further classification of vSMR based on left ventricular ejection fraction (LVEF) ≥40% or <40%. The primary endpoint was all-cause mortality and the secondary endpoint was the composite of all-cause mortality and heart failure (HF) events. RESULTS: Of the total 1061 patients with moderate SMR (age 69±11 years, 59% male) included, 854 (80%) were in NYHA class I-II and 207 (20%) were in NYHA class III-IV. Regarding the aetiology, 352 (33%) had aSMR and 709 (67%) had vSMR, of which 329 (46%) had LVEF ≥40% and 380 (54%) had LVEF <40%. During a median follow-up of 82 (IQR 55-115) months, 397 (37%) died and 539 (51%) patients had HF events or died. On multivariable analysis, NYHA class III-IV (HR 1.578; 95% CI 1.244 to 2.002, p<0.001) and SMR aetiology were independently associated with both endpoints. Specifically, compared to aSMR, vSMR with LVEF ≥40% had a HR of 1.528 (95% CI 1.108 to 2.106, p=0.010) and vSMR with LVEF <40% had a HR of 1.960 (95% CI 1.434 to 2.679, p<0.001). To further support these findings, patients were matched for (1) NYHA class and (2) SMR aetiology by propensity scores including age, sex, diabetes, chronic obstructive pulmonary disease, renal function, left atrial volume index, NYHA class (only for SMR aetiology matching), LVEF, SMR aetiology (only for NYHA class matching), tricuspid regurgitation severity and right ventricular pulmonary artery coupling index. After matching, NYHA class and SMR aetiology remained associated with both outcomes (for both: log rank p<0.050). CONCLUSION: In patients with moderate SMR, distinction in SMR aetiology and assessment of symptoms are important independent determinants of outcome.

Augmented and virtual reality imaging for collaborative planning of structural cardiovascular interventions: a proof-of-concept and validation study.

Purpose: Virtual reality (VR) and augmented reality (AR) have led to significant advancements in cardiac preoperative planning, shaping the world in profound ways. A noticeable gap exists in the availability of a comprehensive multi-user, multi-device mixed reality application that can be used in a multidisciplinary team meeting. Approach: A multi-user, multi-device mixed reality application was developed, supporting AR and VR implementations. Technical validation involved a standardized testing protocol and comparison of AR and VR measurements regarding absolute error and time. Preclinical validation engaged experts in interventional cardiology, evaluating the clinical applicability prior to clinical validation. Clinical validation included patient-specific measurements for five patients in VR compared with standard computed tomography (CT) for preoperative planning. Questionnaires were used at all stages for subjective evaluation. Results: Technical validation, including 106 size measurements, demonstrated an absolute median error of 0.69 mm (0.25 to 1.18 mm) compared with ground truth. The time to complete the entire task was 892 ± 407 s on average, with VR measurements being faster than AR ( 804 ± 483 versus 957 ± 257 s , P = 0.045 ). On clinical validation of five preoperative patients, there was no statistically significant difference between paired CT and VR measurements (0.58 [95% CI, - 1.58 to 2.74], P = 0.586 ). Questionnaires showcased unanimous agreement on the user-friendly nature, effectiveness, and clinical value. Conclusions: The mixed reality application, validated through technical, preclinical, and clinical assessments, demonstrates precision and user-friendliness. Further research of our application is needed to validate the generalizability and impact on patient outcomes.

Clinically Relevant Extracardiac Findings at Cardiac Imaging: Insights from the European MR/CT Registry.

Purpose To determine the prevalence of clinically relevant extracardiac findings at cardiac CT and MRI examinations from a multicenter, multinational MR/CT registry and the relationship of prevalence with examination indications and patient characteristics. Materials and Methods This was a retrospective analysis of data from the European Society of Cardiovascular Radiology MR/CT Registry. Data from 208 506 cardiac CT examinations (median patient age, 66 years [IQR, 55-77]; 121 617 [58.33%] male patients) and 228 462 cardiac MRI examinations (median patient age, 57 years [IQR, 42-69]; 145 792 [63.81%] male patients) entered into the registry between January 2011 and November 2023 were analyzed. Clinically relevant extracardiac findings were defined as findings requiring follow-up examinations or influencing clinical management. The association of examination indication and patient characteristics, including age, with prevalence of extracardiac findings was evaluated using incidence rate ratios (IRRs) derived from multivariable Poisson regression models. Results The prevalence of clinically relevant extracardiac findings was 3.28% (6832 of 208 506) at cardiac CT and 1.50% (3421 of 228 462) at cardiac MRI examinations. Extracardiac findings were more common at CT examinations performed for transcatheter aortic valve replacement (IRR, 2.07; P < .001) and structural heart disease (IRR, 1.44; P < .001) compared with CT performed for coronary artery disease (IRR, 1; reference). Extracardiac findings were more common at MRI examinations performed for myocarditis (IRR, 1.36; P < .001) and structural heart disease (IRR, 1.16; P < .001) than for coronary artery disease. Older patient age was also significantly associated with higher prevalence of extracardiac findings, with an IRR for both CT and MRI examinations of 1.02 (P < .001). Conclusion Data from the multicenter, multinational MR/CT registry indicate that clinically relevant extracardiac findings are present at cardiovascular CT and MRI examinations, and the prevalence of these findings is associated with examination indication and patient age. Keywords: Cardiac Imaging Techniques, Incidental Findings, MRI, CT Angiography, CT, Heart Disease Supplemental material is available for this article. © RSNA, 2024.

Randomised study for the Optimal Treatment of symptomatic patients with low-gradient severe Aortic valve Stenosis and preserved left ventricular ejection fraction (ROTAS trial).

BACKGROUND: The best management of symptomatic patients with low-gradient (LG) severe aortic stenosis (AS) and preserved left ventricular ejection fraction (LVEF) has not been established. The Randomised study for the Optimal Treatment of symptomatic patients with low-gradient severe Aortic valve Stenosis (ROTAS) trial aimed to assess the superiority of aortic valve replacement (AVR) versus medical treatment (MT) in this specific group of AS patients. METHODS: Patients with symptomatic LG severe AS and preserved LVEF (>50%) underwent dobutamine stress echocardiography and/or CT-aortic calcium score to confirm AS severity and were then randomised 1:1 to AVR or MT. The primary endpoint was a composite of overall death and/or cardiovascular hospitalisation. RESULTS: The ROTAS study was stopped early because of insufficient recruitment. In the end, only 52 patients (age 79±7 years; women 54%; NYHA III-IV 27%; median STS score 3.3%) were included in the study. During follow-up (mean: 14±7 months), the primary endpoint occurred in 12 (23%) patients. Compared with MT, AVR was not associated with a significant prognostic benefit (events: 5/26 (19%) vs 7/26 (27%) (HR 0.76, 95% CI 0.24 to 2.39, p=0.63). During follow-up, 11 (42%) patients in the MT group developed class I criteria for AVR or severe symptoms justifying a cross-over to the AVR group. CONCLUSIONS: Because of the small number of included patients and short follow-up the ROTAS trial was underpowered and unable to demonstrate a difference in the study endpoint between treatment arms. In patients in the MT arm, a regular echocardiographic and clinical assessment might be useful to disclose those developing class I indications of AVR or severe AS-related symptoms. TRIAL REGISTRATION NUMBER: NCT01835028.

Standards for conducting and reporting consensus and recommendation documents: European Society of Cardiovascular Radiology policy from the Guidelines Committee.

Cardiovascular imaging is exponentially increasing in the diagnosis, risk stratification, and therapeutic management of patients with cardiovascular disease. The European Society of Cardiovascular Radiology (ESCR) is a non-profit scientific medical society dedicated to promoting and coordinating activities in cardiovascular imaging. The purpose of this paper, written by ESCR committees and Executive board members and approved by the ESCR Executive Board and Guidelines committee, is to codify a standardized approach to creating ESCR scientific documents. Indeed, consensus development methods must be adopted to ensure transparent decision-making that optimizes national and global health and reaches a certain scientific credibility. ESCR consensus documents developed based on a rigorous methodology will improve their scientific impact on the management of patients with cardiac involvement. CRITICAL RELEVANCE STATEMENT: This document aims to codify the methodology for producing consensus documents of the ESCR. These ESCR indications will broaden the scientific quality and credibility of further publications and, consequently, the impact on the diagnostic management of patients with cardiac involvement. KEY POINTS: Cardiovascular imaging is exponentially increasing for diagnosis, risk stratification, and therapeutic management. The ESCR is committed to promoting cardiovascular imaging. A rigorous methodology for ESCR consensus documents will improve their scientific impact.

CT-derived Fractional Flow Reserve: How, When, and Where to use this Novel Cardiac Imaging Tool.

Fractional flow reserve computed tomography (FFRCT) is a novel imaging modality. It utilizes computational fluid dynamics analysis of coronary blood flow obtained from CCTA images to estimate the decrease in pressure across coronary stenosis during the maximum hyperemia. The FFRCT can serve as a valuable tool in the assessment of coronary artery disease (CAD). This non-invasive option can be used as an alternative to the invasive fractional Flow Reserve (FFR) evaluation, which is presently considered the gold standard for evaluating the physiological significance of coronary stenoses. It can help in several clinical situations, including Assessment of Acute and stable chest pain, virtual planning for coronary stenting, and treatment decision-making. Although FFRCT has demonstrated potential clinical applications as a non-invasive imaging technique, it is also crucial to acknowledge its limitations in clinical practice. As a result, it is imperative to meticulously evaluate the advantages and drawbacks of FFRCT individually and contemplate its application in combination with other diagnostic examinations and clinical data.

Perfect Match: Radiomics and Artificial Intelligence in Cardiac Imaging.

Cardiovascular diseases remain a significant health burden, with imaging modalities like echocardiography, cardiac computed tomography, and cardiac magnetic resonance imaging playing a crucial role in diagnosis and prognosis. However, the inherent heterogeneity of these diseases poses challenges, necessitating advanced analytical methods like radiomics and artificial intelligence. Radiomics extracts quantitative features from medical images, capturing intricate patterns and subtle variations that may elude visual inspection. Artificial intelligence techniques, including deep learning, can analyze these features to generate knowledge, define novel imaging biomarkers, and support diagnostic decision-making and outcome prediction. Radiomics and artificial intelligence thus hold promise for significantly enhancing diagnostic and prognostic capabilities in cardiac imaging, paving the way for more personalized and effective patient care. This review explores the synergies between radiomics and artificial intelligence in cardiac imaging, following the radiomics workflow and introducing concepts from both domains. Potential clinical applications, challenges, and limitations are discussed, along with solutions to overcome them.

Usability and accuracy of two different aortic annulus sizing software programs in patients undergoing transcatheter aortic valve replacement.

BACKGROUND: Semi-automated software is essential for planning and prosthesis selection prior transcatheter aortic valve replacement (TAVR). Reliable data on the usability of software programs for planning a TAVR is missing. The aim of this study was to compare software programs 'Valve Assist 2' (GE Healthcare) and 3mensio 'Structural Heart' (Pie Medical Imaging) regarding usability and accuracy of prosthesis size selection in program-inexperienced users. METHODS: Thirty-one participants (n = 31) were recruited and divided into program-inexperienced users (beginners) (n = 22) and experts (n = 9). After software training, beginners evaluated 3 patient cases in 129 measurements (n = 129) using either Valve Assist 2 (n = 11) or Structural Heart (n = 11) on 2 test days (T1, T2). System Usability Scale (SUS) and ISONORM 9241/110-S (ISONORM) questionnaire were used after the test. The valve size selected by each beginner was compared with the valve size selected from expert group. RESULTS: Valve Assist 2 had higher SUS Score: median 78.75 (25th, 75th percentile: 67.50, 85.00) compared to Structural Heart: median 65.00 (25th, 75th percentile: 47.50, 73.75), (p < 0,001, r = 0.557). Also, Valve Assist 2 showed a higher ISONORM score: median 1.05 (25th, 75th percentile: - 0.19, 1.71) compared to Structural Heart with a median 0.05 (25th, 75th percentile: - 0.49, 0.13), (p = 0.036, r = 0.454). Correctly selected valve sizes were stable over time using Valve Assist 2: 72.73% to 69.70% compared to Structural Heart program: 93.94% to 40% (χ2 (1) = 21.10, p < 0.001, φ = 0.579). CONCLUSION: The study shows significant better usability scores for Valve Assist 2 compared to 3mensio Structural Heart in program-inexperienced users.

Aortic geometry and long-term outcome in patients with a repaired coarctation.

OBJECTIVE: This study aims to compare aortic morphology between repaired coarctation patients and controls, and to identify aortic morphological risk factors for hypertension and cardiovascular events (CVEs) in coarctation patients. METHODS: Repaired coarctation patients with computed tomography angiography (CTA) or magnetic resonance angiography (MRA) were included, followed-up and compared with sex-matched and age-matched controls. Three-dimensional aortic shape was reconstructed using patients' CTA or MRA, or four-dimensional flow cardiovascular magnetic resonance in controls, and advanced geometrical characteristics were calculated and visualised using statistical shape modelling. In patients, we examined the association of geometrical characteristics with (1) baseline hypertension, using multivariable logistic regression; and (2) cardiovascular events (CVE, composite of aortic complications, coronary artery disease, ventricular arrhythmias, heart failure hospitalisation, stroke, transient ischaemic attacks and cardiovascular death), using multivariable Cox regression. The least absolute shrinkage and selection operator (LASSO) method selected the most informative multivariable model. RESULTS: Sixty-five repaired coarctation patients (23 years (IQR 19-38)) were included, of which 44 (68%) patients were hypertensive at baseline. After a median follow-up of 8.7 years (IQR 4.8-15.4), 27 CVEs occurred in 20 patients. Aortic arch dimensions were smaller in patients compared with controls (diameter p<0.001, wall surface area p=0.026, volume p=0.007). Patients had more aortic arch torsion (p<0.001) and a higher curvature (p<0.001). No geometrical characteristics were associated with hypertension. LASSO selected left ventricular mass, male sex, tortuosity and age for the multivariable model. Left ventricular mass (p=0.014) was independently associated with CVE, and aortic tortuosity showed a trend towards significance (p=0.070). CONCLUSION: Repaired coarctation patients have a smaller aortic arch and a more tortuous course of the aorta compared with controls. Besides left ventricular mass index, geometrical features might be of importance in long-term risk assessment in coarctation patients.

Combined brain-heart MRI identifies cardiac and white matter lesions in patients with systemic lupus erythematosus and/or antiphospholipid syndrome: A pilot study.

BACKGROUND: Antiphospholipid syndrome (APS) can occur primarily (PAPS) or secondary to another autoimmune disease (SAPS), most commonly systemic lupus erythematosus (SLE). Recently, we reported that subclinical brain involvement was highly prevalent in patients with autoimmune diseases, including SLE. We aimed to investigate whether patients with SLE, PAPS or SAPS and cardiac symptoms showed differences in cardiac/brain involvement based on combined brain-heart magnetic resonance imaging (MRI). METHODS: We prospectively recruited 15 patients with SAPS (86 % with SLE) and 3 patients with PAPS and compared their MRI findings to those of 13 patients with SLE from our previous publication. All patients underwent routine cardiovascular/neurological examination and standard echocardiography. RESULTS: No patients had abnormalities in routine clinical workup/echocardiography. The vast majority had white matter hyperintensities (WMHs) and all had evidence of myocardial fibrosis and/or inflammation. Patients with SAPS had a lower median WMH number [1.00 (1.00, 2.00)] than those with PAPS [3.00 (2.50, 3.00)] or SLE [2.00 (2.00, 3.00)] (p = 0.010). Subcortical and deep WM were highly prevalent. Periventricular WMHs were more frequent in patients with SLE [6 (46.2 %)] or PAPS [2 (66.7 %)] (p = 0.023). Higher lesion burdens (1 WMH vs. 2 WMHs vs. ≥ WMHs) were associated with the presence of cardiac fibrosis [3 (33.3 %) vs. 10 (83.3) vs. 7 (77.8), p = 0.039] and affected the deep and periventricular WM (p < 0.001 for both). CONCLUSION: In patients with PAPS, SAPS or SLE, cardiac symptoms and normal routine workup, combined brain-heart MRI identified abnormalities in both organs in the majority of patients. Combined brain-heart MRI offers excellent diagnostic value, but its incorporation into routine clinical practice should be further investigated. Clinical relevance statement Combined brain-heart magnetic resonance imaging in antiphospholipid syndrome may help to assess the presence of abnormalities in both organs.

Social media for cardiac imagers: a review.

Cardiac imaging plays a pivotal role in the diagnosis and management of cardiovascular diseases. In the burgeoning landscape of digital technology and social media platforms, it becomes essential for cardiac imagers to know how to effectively increase the visibility and the impact of their activity. With the availability of social sites like X (formerly Twitter), Instagram, and Facebook, cardiac imagers can now reach a wider audience and engage with peers, sharing their findings, insights, and discussions. The integration of persistent identifiers, such as digital object identifiers (DOIs), facilitates traceability and citation of cardiac imaging publications across various digital platforms, further enhancing their discoverability. To maximize visibility, practical advice is provided, including the use of visually engaging infographics and videos, as well as the strategic implementation of relevant hashtags and keywords. These techniques can significantly improve the discoverability of cardiac imaging research through search engine optimization and social media algorithms. Tracking impact and engagement is crucial in the digital age, and this review discusses various metrics and tools to gauge the reach and influence of cardiac imaging publications. This includes traditional citation-based metrics and altmetrics. Moreover, this review underscores the importance of creating and updating professional profiles on social platforms and participating in relevant scientific communities online. The adoption of digital technology, social platforms, and a strategic approach to publication sharing can empower cardiac imaging professionals to enhance the visibility and impact of their research, ultimately advancing the field and improving patient care.

Competence of radiologists in cardiac CT and MR imaging in Europe: insights from the ESCR Registry.

RATIONALE: To provide an overview of the current status of cardiac multimodality imaging practices in Europe and radiologist involvement using data from the European Society of Cardiovascular Radiology (ESCR) MRCT-registry. MATERIALS AND METHODS: Numbers on cardiac CT and MRI examinations were extracted from the MRCT-registry of the ESCR, entered between January 2011 and October 2023 (n = 432,265). Data collection included the total/annual numbers of examinations, indications, complications, and reporting habits. RESULTS: Thirty-two countries contributed to the MRCT-registry, including 29 European countries. Between 2011 and 2022, there was a 4.5-fold increase in annually submitted CT examinations, from 3368 to 15,267, and a 3.8-fold increase in MRI examinations, from 3445 to 13,183. The main indications for cardiac CT were suspected coronary artery disease (CAD) (59%) and transcatheter aortic valve replacement planning (21%). The number of patients with intermediate pretest probability who underwent CT for suspected CAD showed an increase from 61% in 2012 to 82% in 2022. The main MRI indications were suspected myocarditis (26%), CAD (21%), and suspected cardiomyopathy (19%). Adverse event rates were very low for CT (0.3%) and MRI (0.7%) examinations. Reporting of CT and MRI examinations was performed mainly by radiologists (respectively 76% and 71%) and, to a lesser degree, in consensus with non-radiologists (19% and 27%, respectively). The remaining examinations (4.9% CT and 1.7% MRI) were reported by non-radiological specialties or in separate readings of radiologists and non-radiologists. CONCLUSIONS: Real-life data on cardiac imaging in Europe using the largest available MRCT-registry demonstrate a considerable increase in examinations over the past years, the vast majority of which are read by radiologists. These findings indicate that radiologists contribute to meeting the increasing demands of competent and effective care in cardiac imaging to a relevant extent. CLINICAL RELEVANCE STATEMENT: The number of cardiac CT and MRI examinations has risen over the past years, and radiologists read the vast majority of these studies as recorded in the MRCT-registry. KEY POINTS: • The number of cardiac imaging examinations is constantly increasing. • Radiologists play a central role in providing cardiac CT and MR imaging services to a large volume of patients. • Cardiac CT and MR imaging examinations performed and read by radiologists show a good safety profile.

Pre-TAVI imaging: an Italian survey by the CT PRotocol optimization (CT-PRO) group.

PURPOSE: The purpose of this survey was to evaluate the current state-of-art of pre-TAVI imaging in a large radiological professional community. METHODS: Between December 2022 and January 2023 all members of the Italian Society of Medical and Interventional Radiology (SIRM) were invited by the CT PRotocol Optimization group (CT-PRO group) to complete an online 24-item questionnaire about pre-TAVI imaging. RESULTS: 557 SIRM members participated in the survey. The greatest part of respondents were consultant radiologists employed in public hospitals and 84% claimed to routinely perform pre-TAVI imaging at their institutions. The most widespread acquisition protocol consisted of an ECG-gated CT angiography (CTA) scan of the aortic root and heart followed by a non-ECG-synchronized CTA of the thorax, abdomen, and pelvis. Contrast agent administration was generally tailored on the patient's body weight with a preference for using high concentration contrast media. The reports were commonly written by radiologists with expertise in cardiovascular imaging, and included all the measurements suggested by current guidelines for adequate pre-procedural planning. About 60% of the subjects affirmed that the Heart Team is present at their institutions, however only 7% of the respondents regularly attended the multidisciplinary meetings. CONCLUSIONS: This survey defines the current pre-TAVI imaging practice in a large radiological professional community. Interestingly, despite the majority of radiologists follow the current guidelines regarding acquisition and reporting of pre-TAVI imaging studies, there is still a noteworthy absence from multidisciplinary meetings and from the Heart Team.

Value Creation Through Artificial Intelligence and Cardiovascular Imaging: A Scientific Statement From the American Heart Association.

Multiple applications for machine learning and artificial intelligence (AI) in cardiovascular imaging are being proposed and developed. However, the processes involved in implementing AI in cardiovascular imaging are highly diverse, varying by imaging modality, patient subtype, features to be extracted and analyzed, and clinical application. This article establishes a framework that defines value from an organizational perspective, followed by value chain analysis to identify the activities in which AI might produce the greatest incremental value creation. The various perspectives that should be considered are highlighted, including clinicians, imagers, hospitals, patients, and payers. Integrating the perspectives of all health care stakeholders is critical for creating value and ensuring the successful deployment of AI tools in a real-world setting. Different AI tools are summarized, along with the unique aspects of AI applications to various cardiac imaging modalities, including cardiac computed tomography, magnetic resonance imaging, and positron emission tomography. AI is applicable and has the potential to add value to cardiovascular imaging at every step along the patient journey, from selecting the more appropriate test to optimizing image acquisition and analysis, interpreting the results for classification and diagnosis, and predicting the risk for major adverse cardiac events.