Detection of cardiac myxomas with non-contrast chest CT

Multimodality Imaging of Benign Primary Cardiac Tumor

Primary cardiac tumors (PCTs) are rare, with benign PCTs being relatively common in approximately 75% of all PCTs. Benign PCTs are usually asymptomatic, and they are found incidentally by imaging. Even if patients present with symptoms, they are usually nonspecific. Before the application of imaging modalities to the heart, our understanding of these tumors is limited to case reports and autopsy studies. The advent and improvement of various imaging technologies have enabled the non-invasive evaluation of benign PCTs. Although echocardiography is the most commonly used imaging examination, it is not the best method to describe the histological characteristics of tumors. At present, cardiac magnetic resonance (CMR) and cardiac computed tomography (CCT) are often used to assess benign PCTs providing detailed information on anatomical and tissue features. In fact, each imaging modality has its own advantages and disadvantages, multimodality imaging uses two or more imaging types to provide valuable complementary information. With the widespread use of multimodality imaging, these techniques play an indispensable role in the management of patients with benign PCTs by providing useful diagnostic and prognostic information to guide treatment. This article reviews the multimodality imaging characterizations of common benign PCTs.

Cardiac myxomas: A narrative review

Cardiac myxomas are common primary neoplasms of the heart. They are biologically benign but “functionally malignant” because of the potential for embolization. They arise most commonly from the left atrium, but no chambers of the heart are immune. They may be sporadic in the majority but also familial as a part of the Carney complex. Two morphological forms exist: polypoid and papillary. Polypoid myxomas often present with obstructive features, while the papillary forms are more prone to embolization. Histogenesis is still controversial; the current view centres around origin from the primitive pluripotent mesenchymal cells. They may be of giant proportion, be calcified or get infected. Clinical presentation typically involves the triad of intracardiac obstruction, embolic events and constitutional symptoms. Precordial examination findings may simulate those of mitral or tricuspid stenosis. The presence of tumour plop and change of the physical findings with changing position may help differentiation between the two. Echocardiography is the investigation of choice. Echogenic polypoid or papillary mobile mass within the atrial cavity remaining attached to the interatrial septum through a stalk are the tell-tale echocardiographic features. Cardiac magnetic resonance and computed tomographic scanning may have incremental diagnostic value. Histopathological examination reveals abundant loose myxoid stroma with scattered round, polygonal or stellate cells with dense irregular nuclei. Genetic testing may detect mutations in the PRKAR1A gene in the familial form of cardiac myxoma, i.e. the Carney complex. Surgical excision is the mainstay of treatment with low operative mortality, excellent postoperative survival and low recurrence rate. The current trend favours minimal-access surgery with or without robotic assistance. Physicians should have appropriate preparedness to make a timely diagnosis and enthusiastic treatment to avoid potentially fatal complications.

Cardiac myxomas: clinical presentation, diagnosis and management

Cardiac myxomas (CM) are the most common type of primary cardiac tumours in adults, which have an approximate incidence of up to 0.2% in some autopsy series. The purpose of this review is to summarise the literature on CM, including clinical presentation, differential diagnosis, work-up including imaging modalities and histopathology, management, and prognosis. CM are benign neoplasms developed from multipotent mesenchyme and usually present as an undifferentiated atrial mass. They are typically pedunculated and attached at the fossa ovalis, on the left side of the atrial septum. Potentially life-threatening, the presence of CM calls for prompt diagnosis and surgical resection. Infrequently asymptomatic, patients with CM exhibit various manifestations, ranging from influenza-like symptoms, heart failure and stroke, to sudden death. Although non-specific, a classic triad for CM involves constitutional, embolic, and obstructive or cardiac symptoms. CM may be purposefully characterised or incidentally diagnosed on an echocardiogram, CT scan or cardiac MRI, all of which can help to differentiate CM from other differentials. Echocardiogram is the first-line imaging technique; however, it is fallible, potentially resulting in uncommonly situated CM being overlooked. The diagnosis of CM can often be established based on clinical, imaging and histopathology features. Definitive diagnosis requires macroscopic and histopathological assessment, including positivity for endothelial cell markers such as CD31 and CD34. Their prognosis is excellent when treated with prompt surgical resection, with postsurgical survival rates analogous to overall survival in the age-matched general population.

Severe functional mitral stenosis due to a left atrial myxoma masquerading as asthma

While cardiac myxomas are the most common primary cardiac tumours, their overall incidence remains rare. Most cases (90%) are sporadic and occur in the third–sixth decades of life with a female predominance and have a specific predilection for the left atrium (75%). While often asymptomatic, clinical presentations depend on the tumour size, architecture and location. Echocardiography remains the mainstay for diagnostic evaluation. Tumour resection is the only definitive treatment. Histopathology using H&E and immunohistochemical stains, such as calretinin and CD34, confirms the diagnosis. We present a case of a patient with reported history of asthma who presented with recurrent acute on chronic shortness of breath refractory to inhaler therapy, multiple outpatient visits and hospitalisations for ‘asthma exacerbations’. After further evaluation, she was diagnosed with a left atrial myxoma attached to the inferior aspect of the intra-atrial septum complicated by severe functional mitral stenosis.

Natural Growth of Left Atrial Myxoma

Myxomas are common benign cardiac tumors that can cause life-threatening events. Urgent surgical excision is needed. Therefore, little is known about their growth rate. We present a peculiar case of an incidental left atrial myxoma offering calculation of a growth curve over more than 6 years. The myxoma was incidentally seen retrospectively on computed tomography scans in follow-up for bladder carcinoma in a 71-year-old patient. The patient underwent surgical resection of the myxoma. The authors emphasize that myxoma can be unnoticed on non-electrocardiogram-gated computed tomography scans. In the presented case, cardiac myxoma appears to grow linearly over time.

Combined PET/CT with thoracic contrast-enhanced CT in assessment of primary cardiac tumors in adult patients

Background

¹⁸F-FDG PET/CT is a key molecular imaging modality to noninvasively assess and differentiate benign and malignant cardiac tumors. However, few benign cardiac tumors can be characterized by increased ¹⁸F-FDG uptake, which makes differential diagnosis difficult. This study sought to retrospectively evaluate whether combined ¹⁸F-FDG PET/CT with thoracic contrast-enhanced CT (CECT) helps in assessing primary cardiac tumors in adult patients, compared with CECT or PET/CT alone.

Methods

Forty-six consecutive patients who were diagnosed as primary cardiac tumors were enrolled. All patients underwent ¹⁸F-FDG PET/CT followed by thoracic CECT before biopsy or surgery. Visual qualitative interpretation and quantitative analysis were performed, and diagnostic performance was evaluated.

Results

More than half (16/29) of benign tumors exhibited with mild ¹⁸F-FDG uptake. There were significant differences in ¹⁸F-FDG uptake and the degree of absolute enhancement between benign and malignant tumors (P < 0.001). The combination of two modalities improved the specificity from 79 to 93%, the positive predictive value from 73 to 89%, and the accuracy of diagnosis from 85 to 93%. There were significant differences between PET/CT alone or thoracic CECT alone and combined modalities (P = 0.034 and P = 0.026, respectively). The combination with the optimal SUVmax cutoff value generated 94% sensitivity, 100% specificity, 97% negative predictive values, 100% positive predictive values, and 98% accuracy rates.

Conclusions

Combining ¹⁸F-FDG PET/C with thoracic CECT significantly improved specificity and accuracy compared to CECT or PET/CT alone in detecting tumors. This combination of diagnostic imaging is effective in differentiating malignant from benign masses.

Primary cardiac tumors associated with genetic syndromes: a comprehensive review

Various cardiac tumors occur in the setting of a genetic syndrome such as myxomas in Carney complex and rhabdomyomas in tuberous sclerosis. Tumor biology can be different in syndromic forms, and on imaging children sometimes demonstrate additional manifestations of the underlying syndrome. We discuss the imaging appearance of cardiac tumors occurring in the framework of a genetic syndrome, the findings that suggest an underlying syndrome, and the impact on management.

Progressive wheeze: atrial myxoma masquerading as chronic obstructive pulmonary disease

Atrial myxoma, the commonest primary cardiac neoplasm, presents with symptoms of heart failure, embolic phenomena or constitutional upset. We present an atypical case, with wheeze and symptomatic exacerbations typical of chronic obstructive pulmonary disease. With no early clinical evidence of heart failure, the patient was managed with inhaled steroids and bronchodilators, with little relief. Only when the patient was in extremis requiring intubation, due to respiratory failure, did clinical evidence of left heart failure become apparent, with echocardiography demonstrating a massive left atrial myxoma obstructing the mitral valve annulus. Following successful surgical resection, the patient's symptoms fully abated. This case highlights the importance of considering cardiac wheeze in those initially managed as obstructive airway disease not responding in a typical fashion to initial bronchodilator therapy, and particularly in those with rapidly progressive symptoms. Such patients should be referred early for cardiac imaging. The excellent prognosis and quick recovery after timely surgical resection of a myxoma are also highlighted.