Computed tomography and nuclear medicine for the assessment of coronary inflammation: clinical applications and perspectives.

There is increasing evidence that in patients with atherosclerotic cardiovascular disease (ASCVD) under optimal medical therapy, a persisting dysregulation of the lipid and glucose metabolism, associated with adipose tissue dysfunction and inflammation, predicts a substantial residual risk of disease progression and cardiovascular events. Despite the inflammatory nature of ASCVD, circulating biomarkers such as high-sensitivity C-reactive protein and interleukins may lack specificity for vascular inflammation. As known, dysfunctional epicardial adipose tissue (EAT) and pericoronary adipose tissue (PCAT) produce pro-inflammatory mediators and promote cellular tissue infiltration triggering further pro-inflammatory mechanisms. The consequent tissue modifications determine the attenuation of PCAT as assessed and measured by coronary computed tomography angiography (CCTA). Recently, relevant studies have demonstrated a correlation between EAT and PCAT and obstructive coronary artery disease, inflammatory plaque status and coronary flow reserve (CFR). In parallel, CFR is well recognized as a marker of coronary vasomotor function that incorporates the haemodynamic effects of epicardial, diffuse and small-vessel disease on myocardial tissue perfusion. An inverse relationship between EAT volume and coronary vascular function and the association of PCAT attenuation and impaired CFR have already been reported. Moreover, many studies demonstrated that 18F-FDG PET is able to detect PCAT inflammation in patients with coronary atherosclerosis. Importantly, the perivascular FAI (fat attenuation index) showed incremental value for the prediction of adverse clinical events beyond traditional risk factors and CCTA indices by providing a quantitative measure of coronary inflammation. As an indicator of increased cardiac mortality, it could guide early targeted primary prevention in a wide spectrum of patients. In this review, we summarize the current evidence regarding the clinical applications and perspectives of EAT and PCAT assessment performed by CCTA and the prognostic information derived by nuclear medicine.

Case Report: Acute Heart Failure Induced by the Combination of Takayasu's, Takotsubo and Coronary Vasospasm in an Elementary School Teacher-A Reaction to Return-to-Work Stress After COVID-19?

Introduction: Takayasu's arteritis (TA) is a systemic inflammatory disease that affects aorta and its major branches. There are several cardiac manifestations of TA and an association with Takotsubo syndrome (TTS) - but not coronary vasospasm - has been previously reported. The role of emotional stress in this context is unknown. Case presentation: A 58-year-old Caucasian female elementary school teacher, with a history of generalized anxiety disorder (GAD), severe asymptomatic aortic regurgitation (AR), and TA in remission under corticosteroids, was admitted in the emergency department with worsening chest pain and dyspnea, initiated after a period of intense emotional stress (increased workload during COVID-19 pandemic). Physical examination revealed signs of heart failure (HF) with hemodynamic stability and an early diastolic heart murmur. The electrocardiogram showed sinus tachycardia, T wave inversion in left precordial and lateral leads, and a corrected QT of 487 ms. Laboratorial evaluation presented high values of high-sensitivity troponin I (3494 ng/L) and B-type natriuretic peptide (4759 pg/mL). The transthoracic echocardiogram revealed severe dilation of left ventricle (LV) with moderate systolic dysfunction, due to apical and midventricular akinesia, and severe AR. The coronary angiography showed normal coronary arteries. An acetylcholine provocative test induced spasm of both the left anterior descending and circumflex arteries, accompanied by chest pain and ST depression, completely reverted after intracoronary nitrates administration. The patient was switched to diltiazem and a drug multitherapy for HF was started. A cardiac magnetic resonance revealed severe dilation of the LV, mild apical hypokinesia, improvement of ejection fraction to 53%, signs of myocardial edema and increased extracellular volume in apical and mid-ventricular anterior and anterolateral walls, and absence of myocardial late gadolinium enhancement, compatible with TTS. At discharge, the patient was clinically stable, without signs of HF, and a progressive reduction of troponin and BNP levels was observed. A final diagnosis of TTS and coronary vasospasm in a patient with GAD and TA was done. Discussion: We present the first case of acute HF showing coexistence of TA, TTS and coronary vasospasm. TA is a rare inflammatory disease that can be associated with TTS and coronary vasospasm. Besides that, coronary vasospasm may also be involved in TTS pathophysiology, suggesting a complex interplay between these diseases. Mood disorders and anxiety influence the response to stress, through a gain of the hypothalamic-pituitary-adrenal axis and an increased cardiovascular system sensitivity to catecholamines. Therefore, although the mechanisms behind these three pathologies are not yet fully studied, this case supports the role of inflammatory and psychiatric diseases in TTS and coronary vasospasm.

Cardiac Care of Non-COVID-19 Patients During the SARS-CoV-2 Pandemic: The Pivotal Role of CCTA.

Aim: The aim of this study is to evaluate the potential use of coronary CT angiography (CCTA) as the sole available non-invasive diagnostic technique for suspected coronary artery disease (CAD) during the coronavirus disease 2019 (COVID-19) pandemic causing limited access to the hospital facilities. Methods and Results: A consecutive cohort of patients with suspected stable CAD and clinical indication to non-invasive test was enrolled in a hub hospital in Milan, Italy, from March 9 to April 30, 2020. Outcome measures were obtained as follows: cardiac death, ST-elevation myocardial infarction (STEMI), non-ST-elevation myocardial infarction (NSTEMI), and unstable angina. All the changes in medical therapy following the result of CCTA were annotated. A total of 58 patients with a mean age of 64 ± 11 years (36 men and 22 women) were enrolled. CCTA showed no CAD in 14 patients (24.1%), non-obstructive CAD in 30 (51.7%) patients, and obstructive CAD in 14 (24.1%) patients. Invasive coronary angiography (ICA) was considered deferrable in 48 (82.8%) patients. No clinical events were recorded after a mean follow-up of 376.4 ± 32.1 days. Changes in the medical therapy were significantly more prevalent in patients with vs. those without CAD at CCTA. Conclusion: The results of the study confirm the capability of CCTA to safely defer ICA in the majority of symptomatic patients and to correctly identify those with critical coronary stenoses necessitating coronary revascularization. This characteristic could be really helpful especially when the hospital resources are limited.

Quantitative Evaluation of COVID-19 Pneumonia Lung Extension by Specific Software and Correlation with Patient Clinical Outcome.

Lung infection named as COVID-19 is an infectious disease caused by the most recently discovered coronavirus 2 (SARS-CoV-2). CT (computed tomography) has been shown to have good sensitivity in comparison with RT-PCR, particularly in early stages. However, CT findings appear to not always be related to a certain clinical severity. The aim of this study is to evaluate a correlation between the percentage of lung parenchyma volume involved with COVID-19 infection (compared to the total lung volume) at baseline diagnosis and correlated to the patient's clinical course (need for ventilator assistance and or death). All patients with suspected COVID-19 lung disease referred to our imaging department for Chest CT from 24 February to 6 April 2020were included in the study. Specific CT features were assessed including the amount of high attenuation areas (HAA) related to lung infection. HAA, defined as the percentage of lung parenchyma above a predefined threshold of -650 (HAA%, HAA/total lung volume), was automatically calculated using a dedicated segmentation software. Lung volumes and CT findings were correlated with patient's clinical course. Logistic regressions were performed to assess the predictive value of clinical, inflammatory and CT parameters for the defined outcome. In the overall population we found an average infected lung volume of 31.4 ± 26.3% while in the subgroup of patients who needed ventilator assistance and who died as well as the patients who died without receiving ventilator assistance the volume of infected lung was significantly higher 41.4 ± 28.5 and 72.7 ± 36.2 (p < 0.001). In logistic regression analysis best predictors for ventilation and death were the presence of air bronchogram (p = 0.006), crazy paving (p = 0.007), peripheral distribution (p < 0.001), age (p = 0.002), fever at admission (p = 0.007), dyspnea (p = 0.002) and cardiovascular comorbidities (p < 0.001). In multivariable analysis, quantitative CT parameters and features added incremental predictive value beyond a model with only clinical parameters (area under the curve, 0.78 vs. 0.74, p = 0.02). Our study demonstrates that quantitative evaluation of lung volume involved by COVID-19 pneumonia helps to predict patient's clinical course.

Extent of lung involvement over severity of cardiac disease for the prediction of adverse outcome in COVID-19 patients with cardiovascular disease.

BACKGROUND: Aim of the present study was to assess if the presence of high cardiovascular risk, left ventricle systolic dysfunction or elevated BNP or Troponin are able to independently predict the outcome of patients with known cardiac disease and COVID-19 pneumonia. METHODS AND RESULTS: From March 7th to April 28th, forty consecutive patients with known cardiac disease (chronic coronary artery disease, n=38; atrial fibrillation, n = 7; valvular disease, n = 13) referred to our emergency department for symptoms of suspected COVID-19, laboratory diagnosis of COVID-19 and typical signs of viral pneumonia at chest CT were enrolled in the study. The only predictor of the composite end-point (all cause of death + invasive ventilation + thromboembolic event) was the lung involvement % at chest CT (OR: 1.06; 95%CI: 1.01-1.11, P = 0.02). In the multivariate analysis, the lung involvement % at chest CT was the only independent predictor of the composite end-point (OR: 1.06; 95%CI: 1.01-1.11, P = 0.034). CONCLUSIONS: The extent of lung involvement by COVID-19 is the only independent predictor of adverse outcome of patients and is predominant over the severity of cardiac disease.

Role of computed tomography in COVID-19.

Coronavirus disease 2019 (COVID-19) has become a rapid worldwide pandemic. While COVID-19 primarily manifests as an interstitial pneumonia and severe acute respiratory distress syndrome, severe involvement of other organs has been documented. In this article, we will review the role of non-contrast chest computed tomography in the diagnosis, follow-up and prognosis of patients affected by COVID-19 pneumonia with a detailed description of the imaging findings that may be encountered. Given that patients with COVID-19 may also suffer from coagulopathy, we will discuss the role of CT pulmonary angiography in the detection of acute pulmonary embolism. Finally, we will describe more advanced applications of CT in the differential diagnosis of myocardial injury with an emphasis on ruling out acute coronary syndrome and myocarditis.