A rare primary right atrial angiosarcoma

Stephen Maharaj¹, Amanda-Marie Mc Carthy², Risshi Rampersad¹, Natasha Rahaman², William R. Torres¹, Jose Martinez¹, Julio Garcia¹, Giovanni Teodori²

¹ Cardiology Department, Caribbean Heart Care Medcorp Ltd., St. Clair Medical Centre, Port of Spain, Trinidad and Tobago.

² Surgical Department, Caribbean Heart Care Medcorp Ltd., St. Clair Medical Centre, Port of Spain, Trinidad and Tobago.

Corresponding Author:
Dr. Stephen Maharaj
Email: [email protected]; [email protected]

DOAJ: ef90140260ab4263ab801396cba87922
DOI: https://doi.org/10.48107/CMJ.2025.09.003
Published Online: September 30, 2025

Copyright: This is an open-access article under the terms of the Creative Commons Attribution License which permits use, distribution, and reproduction in any medium, provided the original work is properly cited.

©2025 The Authors. Caribbean Medical Journal published by Trinidad & Tobago Medical Association

ABSTRACT
Primary cardiac angiosarcoma is a type of rare malignant cardiac neoplasm. These patients usually have a poor prognosis as primary angiosarcomas are associated with early metastasis. Currently, there are no guidelines or effective treatment methods available. Therefore, management relies on previous experience and case reports. We are interested in reporting this case to contribute to the existing knowledge on the topic.

Our report highlights the case of a 22-year-old woman with a right atrial sarcoma who initially presented with severe pericardial effusion with impending Cardiac Tamponade. The patient’s critical condition was stabilized with emergency pericardiocentesis. However, due to the extensive progression of the lesion, surgical resection was the only feasible treatment option.

PRESENTATION OF CASE
A 22-year-old female of East Indian descent with no prior cardiovascular disease nor family history of cardiovascular disease and no significant medical history presented to an emergency department with complaints of shortness of breath for one month. A chest x-ray performed at that institution showed a massive bottle-shaped cardiac silhouette (as seen in figure 1A).

She was then referred to the cardiology unit at another institution for further care. On admission to the facility, she complained of atypical chest pain, cough and shortness of breath for one month. There were no complaints of fever, syncope or palpitations. On physical examination, there were no signs of cardiac tamponade, no distended neck veins or muffled heart sounds, and no hypotension. The blood pressure on admission was 110/80 mmHg, pulse 108, and oxygen saturation was 99% on room air. Significant laboratory investigations included pro- Brain Natriuretic Peptide (401pg/mL), erythrocyte sedimentation rate (15 mm Hr) and D-dimer (2.31mg/L). An ECHO was subsequently performed (as seen in Figure 1 B) that showed an estimated ejection fraction of 66%, severe pericardial effusion with signs of impending cardiac tamponade and a hyperechoic, homogenous fixed mass inside the pericardial sac related to the right atrium which measured 66mm in length and 63mm in thickness with collapsing free wall of the right atrium, normal valves and no intracavitary thrombi.

High resolution CT scan (as seen in figure 1 C) findings revealed a large pericardial effusion of approximately 4.9cm, a right anterior pericardial mass measuring approximately 7.2 x 7.1 cm, and bibasal compressive pulmonary atelectasis, which was more pronounced in the left lung field as opposed to that on the right. The scan also showed a small bilateral pleural effusion.

An urgent ECHO-guided pericardiocentesis was performed under local anaesthesia, and 1.3 L of uncoagulable blood serosanguinous fluid was drained. An 8.5Fr pigtail was left in the pericardium, which drained approximately 1 L of serosanguinous fluid post-pericardiocentesis over 72 hours. The drain was subsequently removed and a post pericardiocentesis ECHO was performed, which showed an estimated ejection fraction of 65%, minimal circumferential pericardial effusion without hemodynamic compromise, a homogenous mass measuring 66 mm x 63 mm related to the free wall of the right atrium, mild tricuspid valve regurgitation, mild pulmonary valve regurgitation, normal aortic and mitral valves anatomy and function and no intracavitary thrombi. The cytology of the pericardial fluid showed an abundance of neutrophils but was negative for malignant cells. The patient was reviewed by the surgical team and surgical resection of the cardiac mass was performed one week after the pericardiocentesis. While awaiting surgery, the patient was managed on colchicine, analgesia and a proton pump inhibitor.

The cardiovascular surgical team excised the pericardial mass from the right atrial wall via median sternotomy and a cardiopulmonary bypass (with aortic and vena caval cannulation) (as seen in Figure 1 D).

Figure 1:  A) Chest X-ray showing an enlarged heart shadow, B) ECHO showing the right atrial mass, C) CT scan showing right atrial tumour, D) Intraoperative photograph of the right atrial tumour during surgery

The patient was then transferred to the ICU in a hemodynamically stable condition, normal Sinus rhythm. A Transthoracic ECHO was done five days post-surgery which showed an estimated ejection fraction of 65%, no mass seen, minimal circumferential pericardial effusion without hemodynamic compromise, normal valves and no intracavitary thrombi.

Histopathology confirmed the diagnosis of angiosarcoma (Classification of soft tissue sarcomas: histological grading with Fédération Nationale des Centres de Lutte Contre le Cancer-FNCLCC: Grade 3) with strong and diffusely positive for CD34 and Ki-67 proliferation index 30-40%. The sections show a spindle cell and vasoformative neoplasm infiltrating cardiac muscle and there are foci with anastomosing vascular spaces lined by markedly atypical cells with enlarged and irregular nuclei in addition to sheets of similarly atypical spindle cells (Fig. 2).

Figure 2: This image shows pathological analysis identifying the tumour as a primary cardiac angiosarcoma: A) The sections show a spindle cell and vasoformative neoplasm infiltrating cardiac muscle and there are foci with anastomosing vascular spaces lined by markedly atypical cells with enlarged and irregular nuclei in addition to sheets of similarly atypical spindle cells, B) Immunohistochemistry showing strongly and diffusely positive for CD34 and Ki-67 proliferation index 30-40%

The postoperative period was uneventful and the patient was discharged six days post procedure. Referral to the oncology unit for adjuvant chemotherapy/radiation therapy was recommended. After consultation with the oncology unit, doxorubicin and isosorbide adjuvant chemotherapy for a total of 6 cycles was commenced. Her post-chemotherapy CT scan was normal with complete resolution of previous pericardial effusion, no evidence of recurrence or residual disease and no metastatic disease within the chest, abdomen or pelvis.

DISCUSSION
Cardiac angiosarcoma is a rare malignant tumour which originates from the endothelial lining of the blood vessels in the heart. It is responsible for approximately 25% of all primary cardiac tumours and is one of the most aggressive and fatal primary cardiac tumours.^(1,2) Unlike secondary cardiac tumours which start from other parts of the body, primary cardiac angiosarcoma originates from within the heart.¹ They often affect the  younger  population (20 – 40 years) but can occur at any age.³  The right side of the heart, particularly the right atrium, is commonly affected, however, other cardiac chambers and structures can also be affected. Sarcomas of the left and right heart have different presentations and characteristics. Left-sided tumours tend to be more solid, less invasive and metastasize later. In contrast, the right-sided tumours tend to be bulkier, more invasive and metastasize earlier.⁴ The defining characteristic of cardiac angiosarcoma is the rapid formation of abnormal blood vessels that infiltrate healthy heart tissue, leading to its destruction. Due to its invasive nature and tendency to metastasize early on, diagnosis and treatment of cardiac angiosarcoma are particularly challenging.

Cardiac angiosarcomas can have diverse and nonspecific clinical presentations, which can lead to delayed diagnosis due to its location within the heart. Dyspnea is the most common symptom followed by fatigue, chest pain, palpitations and sometimes syncope.¹ Other clinical manifestations include valvular dysfunction, pericardial effusion, and cardiac tamponade. The symptoms can be related to the size, location and invasiveness of the tumour and its effect on cardiac function. Metastases commonly occur in the liver, lungs, lymph nodes, bones and adrenal glands. These patients may develop systemic symptoms due to the metastasis which can significantly worsen the prognosis of the disease.

Echocardiography is usually the first test performed to examine patients with suspected cardiac tumours. It assesses the tumour size, mobility and the presence of associated complications such as pericardial effusion or valvular abnormalities. However, there are limitations such as poor description of various tissue types and dependence on the skill and technique of the technician.¹

Cardiac CT scans are very useful in providing a comprehensive understanding of the anatomy of cardiac tumours and identifying the presence of systematic metastasis.¹ They are also helpful in detecting calcifications linking to tumours and assist in transthoracic biopsy.

Cardiac MRI is a superior imaging technique for characterizing soft tissue and differentiating between various abnormalities specific to the myocardium. It can distinguish between thrombi and tumours in the cavity and may show distinct patterns for angiosarcoma, such as a cauliflower-like appearance, or a sunray appearance from a linear contrast along vascular pools. ^(1,5)

To confirm the presence of angiosarcoma, it is necessary to conduct a tissue biopsy. This can be done through surgical resection or open cardiac biopsy, particularly if the tumour is in the right atrium. These methods provide the most accurate diagnosis, compared to pericardiocentesis, pericardial fluid cytology, or even endomyocardial biopsies. The latter has low diagnostic yield and is less effective in diagnosing cardiac angiosarcoma.¹

Histopathological examination and immunohistochemistry are critical in diagnosing primary cardiac angiosarcoma. Microscopic visualization of the tumour shows solid areas of spindle cells, the formation of anastomotic vascular channels by malignant cells, and primary anaplastic cells.^(1,6) In this case, the histological findings showed spindle cells and vasoformative neoplasm infiltrating cardiac muscle as well as foci with anastomosing vascular spaces lined by markedly atypical cells with enlarged and irregular nuclei. To predict the probability of metastases and overall survival, a histological grading is done using three parameters: tumour differentiation, mitotic count and tumour necrosis. The grading system used in this case was FNCLCC (Fédération Nationale des Centres de Lutte Contre le Cancer) which grades from 1, 2 or 3. The grading system is based on the total scores from tumour differentiation, mitotic count, and tumour necrosis. Grade 1 indicates a low-grade tumour, which tends to have a better prognosis. Grade 2 indicates a moderately differentiated soft tissue sarcoma, while Grade 3, or high-grade tumours, are associated with worse outcomes. Any sarcomas that receive a high differentiation score are automatically classified accordingly. In this case, the FNCLCC grade was 3.^(1,6) Immunohistochemistry strains are used to identify the origin of sarcoma when the primary location is unknown. To identify endothelial angiosarcomas, markers such as CD31, CD34, P53 and Ki67 can be seen. In this case, CD34 and Ki67 were seen. Positive straining of CD31 and CD34 shows the presence of vascular lumens throughout the lesion. Ki67 strain determines the proliferation rate which is often associated with poor prognosis outcomes.¹

The current treatment approach for primary cardiac angiosarcoma is surgical resection, followed by adjuvant chemotherapy and/or radiation therapy. ^(1,7) To improve the chance of survival, complete surgical resection of the tumour, in the absence of metastasis, is the first-line treatment.⁷

CONCLUSION
Primary cardiac angiosarcoma is a rare and aggressive tumour that often develops in the right atrium of the heart. Due to its rarity, diagnosis and treatment can be challenging and most cases have reported metastasis and poor prognosis upon diagnosis. The most effective first-line treatment for primary cardiac angiosarcoma is the radical resection of the tumour to achieve optimal survival for patients, particularly if there is no evidence of metastasis, as demonstrated in our case study.

Acknowledgements: Participation by attending and resident medical staff of Caribbean Heart Care Medcorp Ltd is acknowledged.
Ethical approval statement: Approved by the Ethics Review Board under Medcorp Limited with reference number CHCMSM2.
Financial disclosure or funding: Not applicable.
Conflict of interest: The authors declare that there is no conflict of interest.
Informed consent: Written informed consent was obtained from the patient for publication of this case report and images used.
Author contributions: All authors conceived and drafted/edited this manuscript. All authors read and approved the final manuscript.

 REFERENCES

1. Naina Kumari, S. Bhandari, Anzal Ishfaq et al. (2023). Primary Cardiac Angiosarcoma: A Review. Cureus, 15. https://doi.org/10.7759/cureus.41947
2. Bouma, W., Lexis, C.P., Willems, T.P. et al. Successful surgical excision of primary right atrial angiosarcoma. J Cardiothorac Surg6, 47 (2011). https://doi.org/10.1186/1749-8090-6-47
3. Dhaeyer S., Lau CW., Meert V., et al. (2020) Angiosarcoma of the Heart: Case Report. J. Clinical Cardiology and Cardiovascular Interventions, 3(11);https://doi.org/10.31579/2641-0419/100
4. Yadav, A. Mangla (2020). Primary pericardial angiosarcoma: case report and review of treatment options. ecancermedicalscience, 14. https://doi.org/10.3332/ecancer.2020.1056
5. Zhu, L. Guo, Z. Tian et al. (2021). [Clinical and imaging characteristics and prognosis of patients with primary cardiac angiosarcoma]. Zhonghua xin xue guan bing za zhi, 49 4. https://doi.org/10.3760/cma.j.cn112148-20200427-00351
6. Orlandi, A., Ferlosio, A., Roselli, M. et al. (2010). Cardiac Sarcomas: An Update. Journal of Thoracic Oncology, 5(9), 1483-1489. https://doi.org/10.1097/JTO.0b013e3181e59a91
7. Guo, Y., Liu, Q., & Wu, H. (2023). Primary cardiac tumor: A case report of right atrial angiosarcoma and review of the literature. Frontiers in Oncology, 13. https://doi.org/10.3389/fonc.2023.1164153