European Journal of Cardiovascular Medicine

A 45-year-old woman with a history of cervical myelopathy post-fusion and tobacco use presented to the emergency department with a 3-day history of dyspnea, dry cough, high-grade fever (103°F), and generalized malaise. Over the preceding six months, she had experienced intermittent episodes of presyncope and fatigue but had not sought medical attention. On arrival, she appeared acutely ill and in respiratory distress, with vital signs notable for tachycardia (heart rate 140 bpm), tachypnea (24 breaths/min), and hypoxia (oxygen saturation 80% on room air). Cardiovascular examination revealed normal heart sounds without murmurs, and the remainder of the physical exam was unremarkable.

Initial laboratory evaluation showed leukocytosis (WBC 13.06 × 10³/µL), elevated lactate (3.4 mmol/L), procalcitonin (3.99 ng/mL), and anemia with microcytosis (Hb 10.3 g/dL, MCV 67.8 fL). Her D-dimer was significantly elevated at 4869 ng/mL, with mildly elevated troponin (20 ng/L) and proBNP (2443 pg/mL). A respiratory viral panel tested positive for respiratory syncytial virus (RSV). A CT angiogram of the chest performed to evaluate for pulmonary embolism revealed multilobar pneumonia and an incidental finding of a left atrial mass as shown in figures A and B. Transthoracic echocardiography (TTE) confirmed a large left atrial myxoma measuring 6 × 3 cm, prolapsing into the left ventricle.

The patient was started on supportive therapy for RSV pneumonia and transferred to a cardiac surgical center. Preoperative evaluation, including left heart catheterization, confirmed her suitability for surgery. She underwent successful resection of the left atrial myxoma via median sternotomy. Intraoperative findings revealed a large mass originating from the atrial septum. Histopathological analysis confirmed a benign myxoma with areas of hemorrhage, infarction, calcification, and osseous metaplasia. Postoperatively, a follow-up echocardiogram suggested a possible intracardiac thrombus, prompting initiation of apixaban.

During recovery, the patient developed atrial fibrillation with a conversion pause. She was started on oral amiodarone and was closely monitored. She subsequently experienced a junctional rhythm, but was deemed stable for discharge by the electrophysiology team and discharged with a 30-day ambulatory cardiac monitor. By postoperative day 3, she was hemodynamically stable and transferred to the telemetry unit. Her diet was gradually advanced, and she began ambulating independently. Surgical drains were removed on day 4, and she continued to progress well. She was discharged home in stable condition with follow-up arranged with cardiothoracic surgery and cardiology.

Although atrial myxomas are extremely rare (estimated at 0.5–1 case per million annually), a small subset can masquerade as pneumonia-like presentations. [1] Atrial myxomas, though rare, are clinically important due to their risk of causing systemic embolization and intracardiac obstruction. This case highlights the diagnostic difficulty posed by their nonspecific symptoms, which can closely resemble infectious or inflammatory diseases.[2,3]

The patient’s initial presentation with respiratory symptoms and positive RSV testing led to a preliminary diagnosis of viral pneumonia. However, the presence of protracted episodic presyncopal attacks, fatigue and tachycardia prompted further investigation, revealing the left atrial myxoma. Multimodal imaging including CT and TTE played a critical role in establishing the diagnosis. This supports multimodal imaging in evaluating cardiac tumours, especially in patients with atypical clinical presentations, which may easily be mistaken for infectious or inflammatory diseases.  Without this approach, the diagnosis could have been delayed, and in the event of complications like stroke or severe systemic embolic phenomenon, the window for intervention could have been lost. [4] 

Surgical resection remains the gold standard for atrial myxomas. [5] In this case, the excision of the giant myxoma with base involvement of atrial septum was possible. Surgical resection is through a median sternotomy. The patient was managed for postoperative atrial fibrillation which is common in a substantial number of patients undergoing myxoma excision. [6] Patient was managed with amiodarone and anticoagulation. The histopathological findings confirmed the benign nature of the tumor, and the patient recovered well. [7] Several similarities emerge when comparing this case with others. The literature corroborates the epidemiology and clinical presentation of atrial myxomas. As is typical in many other cases of atrial myxomas, the diagnosis was delayed due to the non-specific nature of the clinical symptoms. Evaluation of such reports stresses that large tumors with smooth surfaces or located in unusual zones are more likely to embolize, resulting in severe systemic effects. [8] There was a large tumor base and an embolic potential in this case, thus emphasizing the need for early diagnosis as well as surgery for these high risk patients. Similar to the patient in this report, atrial myxoma affects the majority of patients in adulthood, and women are affected more than men. 

This case emphasizes the importance of maintain a high index of suspicion for atrial myxomas in patients with unexplained systemic or cardiovascular symptoms. Multimodal imaging and timely surgical intervention are crucial for optimal outcomes. Long term follow-up is essential to monitor for recurrence and thromboembolic complications. 

Clinical Question 1

Which of the following clinical features should raise suspicion for atrial myxoma despite an initial diagnosis of viral pneumonia?
A. Productive cough with purulent sputum
B. Positive RSV panel
C. Persistent fatigue and presyncope over months
D. Elevated lactate and leukocytosis

Correct Answer: C. Persistent fatigue and presyncope over months

Explanation: Atrial myxomas frequently present with non-specific systemic symptoms such as fatigue, presyncope, or weight loss. These symptoms, particularly when chronic and unexplained, should prompt evaluation for structural cardiac disease.[7]

Clinical Question 2
What is the definitive treatment for a symptomatic left atrial myxoma?
A. Anticoagulation alone
B. Serial echocardiographic monitoring
C. Surgical excision via median sternotomy
D. Chemotherapy and radiotherapy

Correct Answer: C. Surgical excision via median sternotomy

Explanation: Surgical resection is the only curative approach for atrial myxomas, given the risks of embolization and intracardiac obstruction. Delayed surgery increases morbidity and mortality.[5]

Figure A

Coronal view of contrast-enhanced chest CT angiogram demonstrating a large, well-defined left atrial mass consistent with a left atrial myxoma, seen prolapsing toward the mitral valve.

Figure B

Axial view of contrast-enhanced chest CT angiogram showing a large, well-circumscribed left atrial mass measuring approximately 74.1 mm × 41.9 mm, consistent with a giant left atrial myxoma. The mass is seen occupying the left atrial cavity and prolapsing toward the mitral valve orifice.

Key Learning Points

• Atrial myxomas can mimic respiratory infections, making them a diagnostic challenge when presenting with symptoms like cough, fever, and dyspnea.
• Multimodal imaging including CT chest and echocardiography, is critical for identifying intracardiac masses in atypical presentations.
• Surgical resection is the definitive treatment, and early intervention is crucial to prevent complications such as embolic stroke or sudden cardiac death.

1. Badhey N, Narain A, Chhabra K, Dhamija A. Rapidly emergent left atrial myxoma in asymptomatic young male. 2024;166(4):A4028-A4029.
2. Jaravaza DR, Lalla U, Zaharie SD, de Jager LJ. Unusual presentation of atrial myxoma: a case report and review of the literature. Am J Case Rep. 2021;22:e931437. doi:10.12659/AJCR.931437
3. Settembrini AM, Foresti L, Verlato P, et al. Atrial myxoma presenting as acute lower limb ischemia: case report and scoping review of the literature. 2020;28(3):194-204. doi:10.1177/1708538120905569
4. Hasan M, Abdelmaseih R, Faluk M, Chacko J, Nasser H. Atrial myxoma, a rare cause of sudden cardiac death: a case report and review of literature. 2020;12(12):e6704. doi:10.7759/cureus.6704
5. Maldonado-Suarez J, Del Rio Santiago V, Molina-Lopez VH. Large right atrial myxoma: a rare presentation. 2020;12(10):e54265. doi:10.7759/cureus.54265
6. Settembrini AM, Foresti L, Verlato P, et al. Atrial myxoma presenting as acute lower limb ischemia: case report and scoping review of the literature. 2020;28(3):194-204. doi:10.1177/1708538120905569
7. Pinede L, Duhaut P, Loire R. Clinical presentation of left atrial cardiac myxoma: a series of 112 consecutive cases. Medicine (Baltimore). 2001;80(3):159-172.
8. Shrestha S, Raut A, Jayswal A, Yadav RS, Poudel CM. Atrial myxoma with cerebellar signs: a case report. Case Rep Orthop. 2020;2020:230-238. doi:10.26502/fccm.92920119