Coronary artery disease (CAD) represents a widespread burden to both individual and public health, steadily rising across the globe. The current guidelines recommend non-invasive anatomical or functional testing prior to invasive procedures. Both coronary computed tomography angiography (cCTA) and stress cardiac magnetic resonance imaging (CMR) are appropriate imaging modalities, which are increasingly used in these patients. Both exhibit excellent safety profiles and high diagnostic accuracy. In the last decade, cCTA image quality has improved, radiation exposure has decreased and functional information such as CT-derived fractional flow reserve or perfusion can complement anatomic evaluation. CMR has become more robust and faster, and advances have been made in functional assessment and tissue characterization allowing for earlier and better risk stratification. This review compares both imaging modalities regarding their strengths and weaknesses in the assessment of CAD and aims to give physicians rationales to select the most appropriate modality for individual patients.

BACKGROUND: Cardiac amyloidosis is associated with poor outcomes and is caused by the interstitial deposition of misfolded proteins, typically ATTR (transthyretin) or AL (light chains). Although specific therapies during early disease stages exist, the diagnosis is often only established at an advanced stage. Cardiovascular magnetic resonance (CMR) is the gold standard for imaging suspected myocardial disease. However, differentiating cardiac amyloidosis from hypertrophic cardiomyopathy may be challenging, and a reliable method for an image-based classification of amyloidosis subtypes is lacking. This study sought to investigate a CMR machine learning (ML) algorithm to identify and distinguish cardiac amyloidosis. METHODS: This retrospective, multicenter, multivendor feasibility study included consecutive patients diagnosed with hypertrophic cardiomyopathy or AL/ATTR amyloidosis and healthy volunteers. Standard clinical information, semiautomated CMR imaging data, and qualitative CMR features were integrated into a trained ML algorithm. RESULTS: Four hundred participants (95 healthy, 94 hypertrophic cardiomyopathy, 95 AL, and 116 ATTR) from 56 institutions were included (269 men aged 58.5 [48.4–69.4] years). A 3-stage ML screening cascade sequentially differentiated healthy volunteers from patients, then hypertrophic cardiomyopathy from amyloidosis, and then AL from ATTR. The ML algorithm resulted in an accurate differentiation at each step (area under the curve, 1.0, 0.99, and 0.92, respectively). After reducing included data to demographics and imaging data alone, the performance remained excellent (area under the curve, 0.99, 0.98, and 0.88, respectively), even after removing late gadolinium enhancement imaging data from the model (area under the curve, 1.0, 0.95, 0.86, respectively). CONCLUSIONS: A trained ML model using semiautomated CMR imaging data and patient demographics can accurately identify cardiac amyloidosis and differentiate subtypes.

Background: Acute myocardial injury is a common diagnosis in the emergency department and differential diagnoses are numerous. Cardiac magnetic resonance (CMR) strain sequences, such as fast strain ENCoded (fSENC), are early predictors of myocardial function loss. This study assessed the potential diagnostic and prognostic benefits of a layer-specific approach. Methods: For this prospective study, patients in the emergency department fulfilling rule-in criteria for non-ST-elevation myocardial infarction (NSTEMI) received an ultra-fast fSENC CMR. Volunteers without cardiac diseases (controls) were recruited for comparison. Measurements were performed in a single heartbeat acquisition to measure global longitudinal strain (GLS) and segmental longitudinal strain and dysfunctional segments. The GLS was measured in two layers and a difference (GLS(difference) = GLS(epicardial) - GLS(endocardial)) was calculated. The performance of those strain features was compared to standard care (physical examination, cardiac biomarkers, electrocardiogram). According to the final diagnosis after discharge, patients were divided into groups and followed up for 2 years. Results: A total of 114 participants, including 50 controls, were included. The 64 patients (51 male) were divided into a NSTEMI (25), myocarditis (16), and other myocardial injury group (23). GLS served as a potent predictor of myocardial injury (area under the curve (AUC) 91.8%). The GLS(difference) provided an excellent diagnostic performance to identify a NSTEMI (AUC 83.2%), further improved by including dysfunctional segments (AUC 87.5%, p = 0.01). An optimal test was achieved by adding fSENC to standard care (AUC 95.5%, sensitivity 96.0%, specificity 86.5%, p = 0.03). No death occurred in 2 years for patients with normal GLS and <= 5 dysfunctional segments, while three patients died that showed abnormal GLS or >5 dysfunctional segments. Conclusions: Layer-specific strain is a potential new marker with high diagnostic performance in the identification and differentiation of acute myocardial injuries.

Concerns exist that long-term cardiac alterations occur after severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) infection, particularly in patients who were hospitalized in the acute phase or who remain symptomatic. This study investigates potential long-term functional and morphological alterations after SARS-CoV-2 infection. The authors of this study investigated patients after SARS-CoV-2 infection by using a mobile 1.5T clinical magnetic resonance scanner for cardiac alterations. Cardiac function and dimensions were assessed using a highly efficient cardiac magnetic resonance protocol, which included cine sequences, global longitudinal and circumferential strain assessed by fast-Strain-ENCoded imaging, and T1 and T2 mapping. We assessed symptoms through a questionnaire. Patients were compared with a control group matched for age, gender, body mass index, and body surface area. Median follow-up time was 395 (192-408) days. The final population included 183 participants (age 48.4 ± 14.3 years, 48.1% male (88/183)). During the acute phase of SARS-CoV-2 infection, 27 patients were hospital-admitted. Forty-two patients reported persistent symptoms (shortness of breath, chest pain, palpitations, or leg edema), and 63 reported impaired exercise tolerance. Left ventricular (LV) functional and morphological parameters were within the normal range. T1- and T2-relaxation times were also within the normal range, indicating that the presence of myocardial edema or fibrosis was unlikely. Persistently symptomatic patients showed a slightly reduced indexed LV stroke volume. Functional parameters remained normal in patients who were hospitalized for SARS-CoV-2, persistently symptomatic, or with ongoing impaired exercise tolerance. Irrespective of ongoing symptoms or severity of prior illness, patients who have recovered from SARS-CoV-2 infection demonstrate normal functional and morphological cardiac parameters. Long-term cardiac changes due to SARS-CoV-2 infection appear to be rare.

Introduction: Advanced chronic kidney disease (CKD) is an independent risk factor for coronary artery disease (CAD). Due to its unique uremia-derived pathophysiology of atherosclerosis and the limitations of using potentially harmful contrast agents, the best non-invasive approach to assess CAD in these patients remains unclear. We sought to investigate the accuracy, safety, and prognosis of patients with severe CKD undergoing dobutamine stress cardiac magnetic resonance imaging (CMR).Materials and methods: In this retrospective, single-center study, patients on dialysis or with a glomerular filtration rate of <15 ml/min/1.73 m² who underwent dobutamine stress CMR were included. A rest and stress wall motion analysis was performed using dobutamine/atropine as stressor. The target heart rate was 85% of the maximum heart rate. Periprocedural adverse events and 1-year follow-up data were obtained.Results: A total of 176 patients (127 men, 49 women) with a mean age of 60.9 ± 14.7 years were included, of which 156 patients were on permanent dialysis. Short-term symptoms such as angina or shortness of breath during stress CMR were frequent (22.1%), but major complications were rare (one patient with myocardial infarction, 0.6%). The 1-year event rate was high (16.4%) with a significant independent correlation to reduced ejection fraction at rest (p = 0.037) and failure to achieve the target heart rate (p = 0.029). The overall accuracy for predicting significant CAD was good (sensitivity of 71.4%, specificity of 98.4%) and excellent if the target heart rate was achieved (83.3%, 97.9%). A negative stress CMR was highly predictive for the absence of major adverse cardiac event or any coronary revascularization during the 1-year follow-up (negative predictive value of 95.0%).Discussion: Dobutamine stress CMR is a safe and accurate diagnostic imaging technique in patients at advanced stages of chronic kidney disease. A reduced ejection fraction and the inability to reach the target heart rate are independent predictors of a poor outcome.

Following the world-wide COVID-19 pandemic, many patients reported ongoing severe cardiovascular symptoms after the acute phase. This multisystemic condition has been named long COVID syndrome. Whilst cardiovascular magnetic resonance (CMR) imaging is the gold standard to diagnose acute myocardial damage, no specific changes have been shown in long COVID patients. However, endothelial dysfunction has been hypothesized to contribute to its pathogenesis. Oxygenation-sensitive CMR during breathing exercise is a simple, non-invasive and accurate test to objectify vascular function, that has not been applied to long COVID patients yet. After receiving approval from the local ethics committee, this prospective observational case-control study enrolled (i) patients reporting symptoms for ≥6 weeks following an acute COVID-19 infection or vaccination, and (ii) healthy volunteers with neither symptoms nor history of cardiovascular disease. Participants completed a questionnaire, point-of-care testing of cardiac biomarkers, a standard non-contrast CMR and an oxygenation-sensitive CMR. Heart rate response and breathing-induced myocardial oxygenation reserve (B-MORE) were assessed during metronome-paced hyperventilation and apnea. 31 patients (17 female; age 39.4 [30.3; 51.6] years) and 27 controls (12 female; age 33.3 [27.3; 46.8]) were included with comparable demographics and cardiovascular risk factors between groups. Laboratory testing and standard CMR did not reveal any pathologies in either of the groups. Indexed left ventricular stroke volume was significantly lower in patients (44.5ml [41.2; 46.6] vs. 55.9ml [49.2; 59.2]; p0.05 for all). Vasoactive breathing exercises induced a significant increase in heart rate (+35/min [21; 45]) and B-MORE (9.8% [4.3; 17.2]) in controls. In patients however, heart rate increase was blunted (+15/min [7; 26]; p<0.001) and B-MORE was significantly lower (7.3% [3.4; 10.4], p=0.044). This pilot study is the first to show a blunted hemodynamic and myocardial oxygenation response to vasoactive breathing maneuvers during Oxygenation-sensitive CMR in long COVID patients. This simple, non-invasive test may be the first to objectify complaints of affected patients and indicates evidence for the crucial role of the endothelium in the pathophysiology of long COVID.