Differentiation of cardiac thrombus from cardiac tumor combining cardiac MRI and 18F-FDG-PET/CT Imaging

Multiple thrombi mimicking metastases in the right atrium of patients with non-Hodgkin's lymphoma diagnosed by multimodal cardiac imaging: one case report

BACKGROUND

Right-side heart mass can be found incidentally on routine transthoracic echocardiography (TTE). Accurate diagnosis of cardiac mass often requires more than one imaging method. We present a mid-age woman with non-Hodgkin lymphoma who was found to have multiple right atrial masses mimicking metastases on routine TTE, which were finally diagnosed as thrombi by multimodal cardiac imaging.

CASE PRESENTATION

A 52-year-old woman was diagnosed with primary mediastinal diffuse large B cell lymphoma (DLBCL) almost six months prior. The TTE revealed multiple masses in the right atrium with normal cardiac function when she was being evaluated for the next chemotherapy. On arrival, she was hemodynamically stable and asymptomatic. Physical examination was no remarkable. Laboratory findings showed leukocytosis of 17,900 cells/mm3, hemoglobin of 7.5 mg/dL, and a normal D-dimer level. The suspicious diagnosis of right atrial metastasis was made by TEE. However, the diagnosis of right atrial thrombi was made by contrast CMR. Finally, the 18 F-FDG PET-CT demonstrated no metabolic activity in the right atrium, which further supported the diagnosis of thrombi. Eventually, the masses were removed by cardiopulmonary bypass thoracotomy because of a high risk of pulmonary embolism. Histopathology confirmed the diagnosis of thrombi.

CONCLUSIONS

This case highlights the importance of multimodality cardiac imaging in the appropriate diagnosis of a RA masses in patient of lymphoma. Diagnosis of RA masses can be made using multimodal cardiac imaging like TTE, TEE and CMR, even PET. Echocardiography is the most commonly used on multimodal imaging in cardiac thrombus. CMR has high specificity in differentiating a tumor from thrombus, while 18 F-FDG PET has good sensitivity to determine the nature of the masses.

Multi-modality cardiac image computing: A survey

Multi-modality cardiac imaging plays a key role in the management of patients with cardiovascular diseases. It allows a combination of complementary anatomical, morphological and functional information, increases diagnosis accuracy, and improves the efficacy of cardiovascular interventions and clinical outcomes. Fully-automated processing and quantitative analysis of multi-modality cardiac images could have a direct impact on clinical research and evidence-based patient management. However, these require overcoming significant challenges including inter-modality misalignment and finding optimal methods to integrate information from different modalities. This paper aims to provide a comprehensive review of multi-modality imaging in cardiology, the computing methods, the validation strategies, the related clinical workflows and future perspectives. For the computing methodologies, we have a favored focus on the three tasks, i.e., registration, fusion and segmentation, which generally involve multi-modality imaging data, either combining information from different modalities or transferring information across modalities. The review highlights that multi-modality cardiac imaging data has the potential of wide applicability in the clinic, such as trans-aortic valve implantation guidance, myocardial viability assessment, and catheter ablation therapy and its patient selection. Nevertheless, many challenges remain unsolved, such as missing modality, modality selection, combination of imaging and non-imaging data, and uniform analysis and representation of different modalities. There is also work to do in defining how the well-developed techniques fit in clinical workflows and how much additional and relevant information they introduce. These problems are likely to continue to be an active field of research and the questions to be answered in the future.

Expert review for clinical and translational imaging actionable imaging findings in the daily PET/CT scenario

Background and aim

The American College of Radiology (ACR) defines "actionable findings" the ones requiring a special communication between radiologists and referring clinicians, suggesting to organize their categorization in a three-degree scale on the basis of the risk for the patient to develop complications. These cases may fall in a grey-zone communication between different care figures with the risk of being underestimated or even not being considered at all. In this paper, our aim is to adapt the ACR categorization to the most frequent actionable findings encountered when reporting PET/CT images in a Nuclear Medicine Department, describing the most frequent and relevant imaging features and presenting the modalities of communication and the related clinical interventions that can be modulated by the prognostic severity of the clinical cases.

Materials and methods

We performed a descriptive, observational and critical analysis of the most relevant literature on the topic of "actionable findings", in particular, starting from the reports of the ACR Actionable Reporting Work Group, we categorised and described, in a narrative review, the most relevant "actionable findings" encountered in the Nuclear Medicine PET/CT daily practice.

Results

To the best of our knowledge, to date there are no clear indications on this selective PET/CT topic, considering that the current recommendations target mainly radiologists and assume a certain level of radiological expertise. We resumed and classified the main imaging conditions under the term of "actionable findings" according to the corresponding anatomical districts, and we described their most relevant imaging features (independently of PET avidity or not). Furthermore, a different communication timing and strategy was suggested on the basis of the findings' urgency.

Conclusion

A systematic categorization of the actionable imaging findings according to their prognostic severity may help the reporting physician to choose how and when to communicate with the referring clinician or to identify cases requiring a prompt clinical evaluation. Effective communication is a critical component of diagnostic imaging: timely receipt of the information is more important than the method of delivery.

Massive left atrial thrombus evades multimodality imaging as a myxoma in a bicaval heart transplant recipient

Intracardiac masses are an extremely rare and poorly described complication following a bicaval heart transplantation. We describe the case of an asymptomatic 62-year-old male with a large left atrial mass found incidentally on transthoracic echocardiography 6 years post-transplant. A battery of additional imaging tests was ordered including transesophageal echocardiography, ¹⁸ F-fluorodeoxyglucose positron emission tomography/computed tomography, and T1 and T2 magnetic resonance imaging. Although imaging biomarkers were generally nonspecific, the mass was most consistent with a cardiac myxoma. However, intraoperative findings confirmed by pathology revealed a massive organizing thrombus. The patient had an uneventful recovery after surgical removal of the mass. Our case highlights a very rare phenomenon in heart transplant recipients which remains a unique diagnostic challenge even with current advances in imaging.

An Unusual Cause of Right Heart Failure: Hemorrhagic Pericardial Cyst Presenting as a Pericardial Mass and Constrictive Pericarditis

Congenital pericardial cysts are very rare neoplasms of the middle mediastinum. We report a case of a young woman who was referred to the surgical department with abdominal pain. The ultrasound done showed moderate ascites and pleural effusion. Further evaluation with computed tomography (CT) chest revealed a calcified mass in the pericardium. Follow-up echocardiography showed an echogenic mass in the pericardium. Magnetic resonance imaging (MRI) revealed a hyperintense mass with a delayed enhancement of the contents with features of right heart failure. So, an emergency surgical resection was done that showed a large hemorrhagic mass with pultaceous material in the pericardial cavity. The pathological report confirmed the diagnosis of a hemorrhagic pericardial cyst with organized material.

Assessment of cardiac tumors by 18F-FDG PET/CT imaging: Histological correlation and clinical outcomes

BACKGROUND

To evaluate the diagnostic value of 18F-FDG PET/CT in distinguishing benign versus malignant cardiac tumors as well as to assess its prognostic value.

METHODS

We analyzed 38 patients with cardiac tumors who underwent 18F-FDG PET/CT and followed for median 8.5 ± 12.5 months. SUVmax and TBRmax (maximum tumor-to-background ratio) by receiver-operating characteristic (ROC) curve analysis were used to obtain threshold for the diagnosis of malignancy as defined by histology (n = 38). Survival was assessed and correlated with the dignity of the lesions and PET parameters.

RESULTS

Optimal cut-off values indicating malignancy were as follows: SUVmax = 3.44, with 100% sensitivity and 92.9% specificity, and TBRmax = 1.55, with 95.8% sensitivity and 92.9% specificity. A significant difference of 18F-FDG uptake was observed between primary benign (n = 14, SUVmax = 2.35 ± 1.31, TBRmax = 1.05 ± 0.50) compared to primary malignant cardiac tumors (n = 11, SUVmax = 8.90 ± 4.23, TBRmax = 3.82 ± 1.44) as well as cardiac metastases and lymphoma (n = 13, SUVmax = 14.37 ± 8.05, TBRmax = 6.19 ±  3.38) (all P < .001). Survival rate was significantly lower in patients with malignant as compared to benign cardiac tumors (P < .05). Regression analysis revealed that the lesion dignity determined by the cut-off value of SUVmax was an independent predictor for death in patients with cardiac tumors (P < .05).

CONCLUSION

18F-FDG uptake in cardiac tumors can differentiate between benign and malignant cardiac tumors and predicts survival.

Management of left ventricular thrombus: a narrative review

Left ventricular thrombus (LVT) is a serious complication of acute myocardial infarction (MI) and also non-ischemic cardiomyopathies. We performed a narrative literature review, manual-search of reference lists of included articles and relevant reviews. Our literature review indicates that the incidence of LVT following acute MI has decreased, probably due to improvement in patient care as a result of better and earlier reperfusion techniques. Predictors of LVT include anterior MI, involvement of left ventricular (LV) apex (regardless of the coronary territory affected), LV akinesis or dyskinesis, reduced LV ejection fraction (LVEF), severe diastolic dysfunction and large infarct size. LVT is associated with increased risk of systemic embolism, stroke, cardiovascular events and death, and there is evidence that anticoagulant therapy for at least 3 months can reduce the risk of these events. Cardiac magnetic resonance (CMR) has the highest diagnostic accuracy for LVT, followed by echocardiography with the use of echocardiographic contrast agents (ECAs). Although current guidelines suggest use of vitamin K antagonist (VKA) for a minimum of 3 to 6 months, there is growing evidence of the benefits of direct acting oral anticoagulants in treatment of LVT. Embolic events appear to occur even after resolution of LVT suggesting that anticoagulant therapy needs to be considered for a longer period in some cases. Recommendations for the use of triple therapy in the presence of the LVT are mostly based on extrapolation from outcome data in patients with atrial fibrillation (AF) and MI. We conclude that the presence of LVT is more likely in patients with anterior ST-segment elevation MI (STEMI) (involving the apex) and reduced ejection fraction (EF). LVT should be considered a marker of increased long-term thrombotic risk that may persist even after thrombus resolution. Ongoing clinical trials are expected to elucidate the best management strategies for patients with LVT.

Myocardial Metastasis of Tongue Cancer: A Rare Localization

Patient: Male, 72-year-old

Final Diagnosis: Metastatic squamous cell carcinoma

Symptoms: None

Medication:—

Clinical Procedure: —

Specialty: Cardiology

Masses in right side of the heart: spectrum of imaging findings

Primary heart tumors are rare, benign tumors represent the majority of these. If a cardiac mass is found, the probability that it is a metastasis or a so-called “pseudo-mass” is extremely higher than a primary tumor. The detection of a heart mass during a transthoracic echocardiography (TE) is often unexpected. The TE assessment can be difficult, particularly if the mass is located at the level of the right chambers. Cardiac Computed Tomography (CCT) can be useful in anatomical evaluation and Cardiac Magnetic Resonance (CMR) for masses characterization as well. We provide an overview of right cardiac masses and their imaging futures. (www.actabiomedica.it)

Assessment of Cardiac Masses by Cardiac Magnetic Resonance Imaging: Histological Correlation and Clinical Outcomes

Background

Cardiac magnetic resonance imaging (CMR) provides useful information for characterizing cardiac masses, but there are limited data on whether CMR can accurately distinguish benign from malignant lesions. We aimed to describe the distribution and imaging characteristics of cardiac masses identified by CMR and to determine the diagnostic accuracy of CMR for distinguishing benign from malignant tumors.

Methods and Results

We examined consecutive patients referred for CMR between May 2008 and August 2013 to identify those with a cardiac mass. In patients for whom there was histological correlation, 2 investigators blinded to all data analyzed the CMR images to categorize the mass as benign or malignant. For benign masses, readers were also asked to specify the most likely diagnosis. Benign masses were defined as benign neoplastic or non‐neoplastic. Malignant masses were defined as primary cardiac or metastatic. Of 8069 patients (mean age: 58±16 years; 55% female) undergoing CMR, 145 (1.8%) had a cardiac mass. In most cases (142, 98%), there was a known cardiac mass before the CMR study. Among 145 patients with a cardiac mass, 93 (64%) had a known history of malignancy. Among 53 cases that had histological correlation, 25 (47%) were benign, 26 (49%) were metastatic, and 2 (4%) were malignant primary cardiac masses. Blinded readers correctly diagnosed 89% to 94% of the cases as benign versus malignant, with a 95% agreement rate (κ=0.83).

Conclusions

Although CMR can be highly effective in distinguishing benign from malignant lesions, pathology remains the gold standard in accurately determining the type of mass.

Role of Imaging for Suspected Cardiac Thrombus

PURPOSE OF REVIEW

Cardiac thrombus formation is a frequent complication of a variety of prevalent diseases. Embolism of cardiac thrombus has the potential to result in significant morbidity and mortality from cerebrovascular and peripheral vascular events.

RECENT FINDINGS

Echocardiography is the most commonly used imaging modality for diagnosing intracardiac thrombus. However, technological advances in computed tomography and magnetic resonance imaging have allowed newer noninvasive modalities to evolve into robust tools for the clinical evaluation of patients suspected of disease. Complimentary use of these imaging techniques is crucial in the diagnosis of cardiac thrombus and initiation of anticoagulation therapy.

Impact of ST-segment elevation on the outcome of Takotsubo syndrome

Background

Recent studies have highlighted that Takotsubo syndrome (TTS), mimicking acute coronary syndrome (ACS), is associated with poor clinical outcome. TTS is associated with different repolarization disorders including ST-segment elevation. ST elevation myocardial infarction (STEMI) in ACS is associated with declined prognosis. However, the clinical and prognostic impact of ST-segment elevation on TTS remains lacking.

Aim

The aim of this study was to determine the short- and long-term prognostic impact of ST-segment elevation on TTS patients as compared with STEMI patients.

Patients and methods

Our institutional database constituted a consecutive cohort of 138 TTS patients and 138 ACS patients matched for age and sex. TTS patients (n=41) with ST-segment elevation were compared with ACS patients with ST-segment elevation (n=64).

Results

Chest pain was significantly more documented in STEMI patients as compared with TTS patients (48.8% vs 78.1%; P<0.01). Cardiovascular risk factors such as diabetes mellitus (12.2% vs 29.7%; P=0.02) were significantly more presented in STEMI patients. Although the initial left ventricular ejection fraction (LVEF) was more declined in TTS patients (39%±9% vs 45%±16%; P<0.01), the LVEF was more declined in STEMI patients at follow-up (54%±10% vs 45%±16%; P=0.04). Inhospital complications such as respiratory failure were significantly more presented in TTS patients (68.3% vs 20.3%; P<0.01). The short-term as well as the long-term morality was similar in both groups. In univariate analysis, male sex, ejection fraction (EF) <35%, glomerular filtration rate (GFR) <60 mL/min, cardiogenic shock, inotropic drugs, and history of cancer were predictors of 5-year mortality.

Conclusion

Rates of the long-term mortality in TTS patients with ST elevations are comparable with STEMI patients.

Pitfalls and Misinterpretations of Cardiac Findings on PET/CT Imaging: A Careful Look at the Heart in Oncology Patients

Positron emission tomography (PET) computed tomography (CT) with 2-[fluorine-18] fluoro-2-deoxy-d-glucose (FDG) has been established as an effective modality for evaluation of cancer. Interpretations of patterns of physiologic ¹⁸F-FDG uptake by the heart is particularly difficult given the wide normal variations of ¹⁸F-FDG metabolic activity observed. Atypical patterns of focal or diffuse physiologic cardiac ¹⁸F-FDG uptake and post-therapeutic effects after radiation therapy, systemic diseases, or cardiomyopathy may also be confused with malignant disease on ¹⁸F-FDG PET/CT. In this article, we review the variations of normal cardiac ¹⁸F-FDG uptake observed in oncology patients and the appearances of other patterns of pathologic metabolic activity, related or not related to the malignancy being investigated, that may lead to false-negative and false-positive results.

Precision Medicine and PET/Computed Tomography in Cardiovascular Disorders

PET/computed tomography (CT) can evaluate the metabolic and anatomic involvement of a variety of inflammatory, infectious, and malignant cardiovascular disorders. PET/CT is useful in evaluating coronary vasculature, hibernating myocardium, cardiac sarcoidosis, cardiac amyloidosis, cerebrovascular disease, acute aortic syndromes, cardiac and vascular neoplasms, cardiac and vascular infections, and vasculitis. Novel targeted radiopharmaceutical agents and novel use of established techniques show promise in diagnosing and monitoring cardiovascular diseases.

Native aortic valve thrombosis in patient with protein S deficiency

Native aortic valve thrombosis is an extremely rare condition, the causes of which include previous aortic valve diseases, endocarditis, valvular injury by a catheter intervention and an underlying hypercoagulative state. Its diagnosis is important for preventing life-threatening embolic complications. Here, we report a case of native aortic valve thrombosis and recurrent systemic embolism in a patient with protein S deficiency, a disorder associated with a hypercoagulative state.

Takotsubo Syndrome and Embolic Events

Takotsubo cardiomyopathy (TTC), initially defined as a benign disease, is associated with several complications. One of them is a thromboembolism, which is clinically presented by events such as stroke, ventricular thrombi, and peripheral embolization, and can be present at index event of TCC as well as at any time in disease course. Patients with elevated C-reactive protein levels, markedly elevated D-dimers and severely impaired left ventricular function seem to be at higher risk of developing thrombemboli. Treatment strategies prescribed in the management of thombembolic complications in patients with acute myocardial infarction includes a short course of anticoagulation. A similar analogy could also be considered for patients with TTC presenting with this complications. Nevertheless, an individualized close-follow-up is of utmost importance to avoid any relapse and not to oversee any impeding complications in light of dynamic processes in myocardial stunning.

Cardiac Magnetic Resonance for Evaluating Catheter Related FDG Avidity

A 53-year-old female with a history of metastatic left arm melanoma presented for F(18) fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) which showed a moderately FDG avid focus at her port catheter tip near the cavoatrial junction. Although catheter tip related FDG avidity has previously been suggested to be bland thrombus or infection, melanoma can metastasize to unusual locations including the superior vena cava. In addition, the patient had an elevated risk of anticoagulation due to a history of hemorrhagic brain metastases. Therefore, confirmatory cardiac magnetic resonance (CMR) was obtained and findings were consistent with bland catheter-related thrombus.