Left Atrial Thrombus Masquerading as a Myxoma in a Patient with Mitral Stenosis

An Unusual Case of Cardiac Mass: A Multimodal Approach in Diagnosis and Treatment

Diagnosing intracardiac masses poses a complex, multimodal challenge. We present the case of a 72-year-old woman with a history of rheumatic fever leading to mitral stenosis and a previous mitral valve commissurotomy who reported fatigue, weakness, and palpitations over the past three months. Echocardiography revealed a tumor (53 × 40 mm) in the enlarged left atrium, attached by a wide base to the left atrium wall, exhibiting variable densities. Computerized tomography identified a heterodense mass (53 × 46 × 37 mm) with similar attachments. Angiography showed two branches from the circumflex artery intricately associated with the mass. Despite unsuccessful embolization of the mass' blood supply, surgical intervention including mitral valve replacement, tricuspid valve annuloplasty, and tumor removal was pursued. Pathohistological analysis confirmed the mass as a thrombus. During the postoperative follow-up, the patient presented with no complaints. Follow-up echocardiography indicated the normal function of the mechanical mitral valve prosthesis and the absence of intracardiac masses. While it remains unknown whether this neovascularization is specific to patients with severe mitral valve disease, this case highlights the diagnostic challenges of differentiating between thrombi and tumors in the context of mitral valve disease. It illustrates the critical role of multimodal imaging in elucidating the anatomical and functional relationships within the heart, thereby guiding accurate diagnosis and effective treatment.

Massive Mural Thrombus Masquerading as Myxoma

A 75-year-old Caucasian female with a past medical history including insulin-dependent diabetes mellitus, hypertension, and dyslipidemia, presented to the emergency room for having palpitations for three weeks. Echocardiography revealed a very large left atrial mass mimicking myxoma. Mass was excised and examined by pathology, revealing a mural thrombus. A mural thrombus is not an uncommon mass found in the left atrium. However, it does not often present symptomatically, strongly mimics an atrial myxoma on cardiac imaging, and has rarely ever been reported to be greater than seven centimeters in any dimension. We present a case of a 75-year-old Caucasian woman with a massive, symptomatic cardiac thrombus masquerading as a myxoma on imaging.

Comparison of Clinical and Echocardiographic Characteristics between Cardiac Myxomas and Masses Mimicking Myxoma

BACKGROUND AND OBJECTIVES

Cardiac myxoma is the most frequent benign cardiac tumor that can result in cardiac and systemic symptoms. We investigated clinical and echocardiographic characteristics of patients with cardiac masses suggesting myxoma.

METHODS

We investigated 265 consecutive patients with an echocardiographic diagnosis of cardiac myxomas in 4 teaching hospitals in Korea.

RESULTS

The mean age was 61±16 years and 169 patients (63.8%) were female. The most frequent referral reason for echocardiography was an evaluation of cardiac symptoms (43.4%). Tumors were incidentally detected in 82 patients (30.9%). Left atrium (LA) was the most frequently involved site (84.5%) and 19 patients (7.2%) had non-atrial tumors. The mean tumor size was 38.7×26.0 mm (range, 4-96 mm). Of 186 patients (70.2%) who had pathological diagnosis, 174 (93.5%) were confirmed with myxoma, 8 (4.3%) with other tumors and 4 (2.2%) with thrombi. Compared to myxoma, smaller size (20.4×12.6 mm vs. 41.4×27.6 mm, p<0.01) and non-LA location (87.5% vs. 10.5%, p<0.001) were associated with non-myxoma tumors, and more frequent atrial fibrillation (AF, 75.0% vs. 7.0%, p<0.001) and larger LA diameter (55.0±14.6 mm vs. 41.3±7.7 mm, p=0.001) were related to thrombi.

CONCLUSIONS

Of 265 patients with an echocardiographic diagnosis with cardiac myxomas, 174 (65.7%) were surgically confirmed with myxomas. Compared with cardiac myxoma, other tumors were smaller and more frequently found in non-atrial sites. Thrombi were associated with AF and larger LA diameter.

Cardiac Tumors: Echocardiographic Diagnosis and Forensic Correlations

In the past, cardiac tumors were a just clinical curiosity and the prognosis was poor. Surgical management became possible after the advent of cardiopulmonary bypass, and more recently, preoperative diagnosis was greatly improved by the development of echocardiography, computed tomography, and magnetic resonance imaging. The value of echocardiography for diagnosing cardiac mass lesions has become well established. Numerous advances have occurred in the last 5 decades, and the evolution of echocardiography involves the development of its many modalities. This review is intended to help echocardiologists and forensic pathologists in providing good medical practice when faced with the challenge of investigating unexpected clinical signs, particularly in young people, or unexpected postmortem findings.

Biatrial thrombi resembling myxoma regressed after prolonged anticoagulation in a patient with mitral stenosis: a case report

Background

Many cases of cardiac masses have been reported in the literature, but in this case report we described a rare case of biatrial cardiac mass that represented a challenge for diagnosis and therapy. The differentiation between cardiac masses such as thrombi, vegetations, myxomas and other tumors is not always straightforward and an exact diagnosis is important because of its distinct treatment strategy. Transthoracic/esophageal echocardiography and cardiac magnetic resonance play an important role in establishing the diagnosis of cardiac masses. However, no current noninvasive diagnostic tool has the ability to absolutely diagnose cardiac masses; obtaining a pathological specimen by surgical resection of cardiac masses is the only reliable method to diagnose cardiac masses accurately. Our case report is an exception in that the final diagnosis was affirmed by empirical anticoagulation therapy based on clinical judgment and noninvasive characterization of biatrial mass.

Case presentation

We described a 54-year-old Malay man with severe mitral stenosis and atrial fibrillation who presented with a biatrial mass. Transthoracic/esophageal echocardiography and cardiac magnetic resonance detected a large, homogeneous right atrial mass typical of a thrombus, and a left atrial mass adhering to interatrial septum that mimicked atrial myxoma. The risk factors, morphology, location, and characteristics of the biatrial cardiac mass indicated a diagnosis of thrombi. However, our patient declined surgery. As a result, the nature of his cardiac masses was not specified by histology. Of note, his left atrial mass was completely regressed by long-term warfarin, leaving a residual right atrial mass. Thus, we affirmed the most probable diagnosis of cardiac thrombi. During the course of treatment, he had an episode of non-fatal ischemic stroke most probably because of a thromboembolism.

Conclusions

Noninvasive characterization of cardiac mass is essential in clarifying the diagnosis and directing treatment strategy. Anticoagulation is a feasible treatment when the clinical assessment, risk factors, and imaging findings indicate a diagnosis of thrombi. After prolonged anticoagulation therapy, complete resolution of biatrial thrombi was achievable in our case.

Cardiac myxoma in Iceland: a case series with an estimation of population incidence

Cardiac myxoma (CM) is the most common primary benign tumor of the heart, but the true age-standardized incidence rate (ASR) has remained unknown. We therefore used nationwide registries in Iceland to study CM and establish its incidence rate. This was a retrospective study involving all patients diagnosed with CM in Iceland between 1986 and 2010. Cases were identified through three different registries, and hospital charts and histology results reviewed. An ASR was estimated based on a world standard population (w). Nine cases of CM (six women) were identified with a mean age of 62.8 years (range: 37-85), giving an ASR of 0.11 (95% CI: 0.05-0.22) per 100,000. The mean tumor size was 4.4 cm (range: 1.5-8.0) with all the tumors located in the left atrium. Dyspnea (n = 6) and ischemic stroke (n = 2) were the most common symptoms. All patients underwent complete resection of the tumor and there were no postoperative deaths or CM-related deaths at follow-up (mean 85 months). The ASR of CM in Iceland was 0.11 per 100,000. To our knowledge, this is the first study to determine the incidence of CM in an entire population. In Iceland, the presenting symptoms and mode of detection of CM are similar to those in other series.