Place of MRI in the Diagnosis of Intracardiac Masses

Amina Elfhal *¹

*Correspondence to: Dr. Amina Elfhal, Professor Jérôme Garot, Paris South Cardiovascular Institute (ICPS) – MASSY, Paris-France.

              
Copyright.

© 2025 Amina Elfhal This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Received: 26  May 2025

Published: 01 July 2025

DOI: https://doi.org/10.5281/zenodo.15838054

1. Introduction

Intracardiac masses represent a common diagnostic challenge in cardiovascular imaging. Their detection can be incidental or motivated by symptoms such as systemic embolism, rhythm disturbances, or heart failure. In this context, imaging plays a fundamental role in characterizing these abnormalities, guiding the therapeutic strategy, and directing toward a surgical or medical approach.

Among the various imaging modalities available, cardiac magnetic resonance imaging (MRI) has established itself as a reference tool for tissue characterization of cardiac masses. It allows multiplanar analysis without irradiation, excellent contrast resolution and precise functional assessment, making it essential in the assessment of cardiac tumors and their differential diagnoses.

The objective of this article is to highlight the current place of MRI in the diagnosis of intracardiac masses, by integrating data from recent literature and current recommendations.

 

2. Classification of intracardiac masses

Intracardiac masses represent a heterogeneous spectrum of pathological entities that can be tumoral, thrombotic, infectious, or even congenital in origin. It is crucial to establish a rigorous classification, as treatment and prognosis differ radically depending on the nature of the mass.

 

2.1 Benign tumors

They represent approximately 75% of primary cardiac tumors. Although histologically benign, their intracardiac location can lead to major hemodynamic consequences or embolic events.

• Myxoma : the most common in adults (approximately 50% of cases). It is generally located in the left atrium, inserted at the level of the interatrial septum, often mobile. It can cause syncope, embolisms or functional mitral obstruction.
• Lipoma : made up of adipose tissue, often well-defined, without enhancement after gadolinium, iso- or hyperintense in T1, losing the signal in sequence with fat suppression.
• Fibroma : hard benign tumor, often intramyocardial , common in children, classically isointense in T1, hypointense in T2, and intense enhancement in LGE.
• Rhabdomyoma : typical of infants, often multiple and intramyocardial , spontaneously regressive. Often associated with tuberous sclerosis of Bourneville.
• Hemangioma or fibroelastic papilloma : rarer, but possibly valvular in location.

 

2.2 Primary malignant tumors

2.2.1Primary malignant tumors

Less than 25% of primary tumors are malignant, but they have locally aggressive behavior and a poor prognosis.

• Angiosarcoma : The most common cardiac sarcoma, usually in the right atrium, often necrotic, heterogeneous, and highly vascularized. It invades the pericardium and causes hemorrhagic effusions.
• Primary cardiac lymphoma : rare, mainly affects immunocompromised patients (HIV, post-transplant). Frequently located in the pericardium or right cavities. Enhancement after gadolinium is intense.
• Undifferentiated sarcoma, leiomyosarcoma : invasive, poorly defined masses with heterogeneous enhancement and frequent pericardial extension.

2.2.2 Secondary tumors

Much more frequent than primary tumors. Involvement can occur by contiguity, by lymphatic, hematogenous route or by transvenous extension .

• Origin: lung cancer, breast cancer, melanoma, lymphoma, leukemia, kidney cancer
• May affect the myocardium, pericardium (with effusion), right cavities (by tumor embolism).
• Often multiple, poorly defined, infiltrating, variable enhancement depending on the tumor type.

 

2.3 Intracardiac pseudotumors

They represent frequent diagnostic pitfalls.

• Thrombus : Typically non-vascularized, hypointense in T1 and T2, without enhancement after gadolinium. The dynamic perfusion sequence is very useful for eliminating a tumor.
• Vegetations : grafted onto valves in an infectious context. Highly mobile, echogenic on ultrasound, rarely visualized directly on MRI.
• Pericardial/hydatid cysts : homogeneous fluid content, very hyperintense in T2, without post-gadolinium enhancement. CT scan or hydatid serology may be useful in addition.
• Pseudo-tumoral aneurysms : particularly in old infarcts with mural thrombus or thinned scar

 

3. Cardiac MRI technique applied to intracardiac masses

Cardiac MRI provides a comprehensive approach to the mass, combining morphological analysis, tissue characterization, and dynamic assessment. The acquisition strategy is based on several complementary sequences, standardized according to SCMR (Society for Cardiovascular Magnetic Resonance ) recommendations .

3.1 Morphology and mobility sequences

• Cine SSFP ( Steady -State Free Precession ) sequences : acquired in apnea on the 2nd, 3rd, 4th cavity and minor axis planes. They allow:
  • To locate the mass
  • To appreciate its mobility (mobile = emboligenic?)
  • To assess the hemodynamic impact (valvular obstruction, cavitary impact)
• 3D tracking sequences : sometimes useful for visualizing the extent of a large or infiltrating tumor.

3.2 Tissue characterization sequences

• T1-weighted : useful for detecting masses rich in fat or protein (lipomas, cysts).
• T2-weighted / STIR : to assess edema or necrosis (often seen in sarcomas or lymphomas).
• Fat-suppressed sequences : to differentiate lipoma vs. mass with non-specific fatty component.

3.3 Infusion sequences and late enhancement

• First pass infusion after gadolinium injection :
  • If the mass is vascularized → suspicion of tumor
  • If no perfusion → promotes a thrombus
• LGE ( Late Gadolinium Enhancement ) :
  • Acquisition 10–15 minutes after injection.
  • The intense and heterogeneous enhancement suggests a malignant tumor.
  • The absence of enhancement (black appearance) is very suggestive of an organized thrombus.

3.4 Technical parameters

• ECG synchronization essential (acquisition in diastole preferably).
• Apnea during motion-sensitive sequences (SSFP, LGE).
• Planning oriented along the axis of the mass (sometimes with atypical cuts).
• Isotropic 3D sequences sometimes necessary for surgical planning.

 

4. Diagnostic contributions of MRI

Magnetic resonance imaging plays a central role in the evaluation of intracardiac masses, due to its unique ability to provide morphological, functional, and tissue information. Unlike other imaging modalities, MRI allows for in-depth characterization of the nature of masses, making it a leading tool in the diagnostic approach.

One of the main advantages of MRI is its ability to characterize the tissue composing the mass. Thanks to the combined use of T1- and T2-weighted sequences, associated with late enhancement sequences after injection of gadolinium, MRI makes it possible to determine the tissue composition of the mass: fatty, fibrous, myxoid, cystic, hemorrhagic or necrotic. This detailed analysis often reliably guides towards a benign or malignant etiology, thus reducing the need for invasive procedures such as intracardiac biopsy.

A fundamental diagnostic contribution of MRI lies in its ability to differentiate a tumor from a thrombus. A thrombus is characterized by the absence of perfusion in the first gadolinium pass and by a hypointense signal in late enhancement, reflecting the absence of vascularization and living tissue. Conversely, a tumor, even a benign one, shows active perfusion and, in most cases, significant late enhancement, which is often heterogeneous in the case of malignant tumors. This distinction is crucial, particularly in contexts where the therapeutic stakes are high, such as in the choice between anticoagulation or surgery.

MRI also provides a precise analysis of the location of the mass, its anatomical relationships with adjacent structures, and its potential for myocardial or pericardial infiltration. Gradient echo cine sequences allow the study of the mobility of the mass, an essential criterion for assessing embolic risk, particularly for pedunculated tumors such as myxoma. MRI is also very effective for assessing the mechanical effect of a mass on valves or intracavitary flow.

Finally, MRI can diagnose many pseudotumors, such as pericardial or hydatid cysts, post-infarction remodeled aneurysms, or certain normal structures (papillary muscles, bands), which can be confusing on ultrasound. Analysis of the content, the absence of enhancement, and the intensity of the T2 signal often make it possible to remove these diagnostic doubts.

 

5. MRI and management strategy

The impact of cardiac MRI extends far beyond diagnostics, directly influencing therapeutic decisions and multidisciplinary management choices. By providing reliable information on the nature, location, extent, and dynamic behavior of the mass, MRI allows for tailoring the therapeutic strategy to each clinical situation.

In the case of benign tumors, such as myxomas, MRI can confirm the diagnosis and specify the point of attachment, mobility and hemodynamic consequences, which are determining factors for the surgical indication. A mobile pedunculated mass, especially if it is associated with embolic events or valvular obstruction, requires curative surgical treatment. MRI plays an essential role here in guiding surgical planning and anticipating possible technical difficulties, particularly in the case of a large tumor or intramyocardial extension.

In more complex situations involving primary malignant tumors or cardiac metastases, MRI can define the locoregional extension of the lesion and its infiltrative nature. It thus contributes to disease staging, the identification of critical invaded structures, and the assessment of the feasibility of resection. In these cases, MRI also contributes to diagnostic orientation by suggesting a probable histological type, which can guide a targeted biopsy on a more accessible extracardiac site. It is fully integrated into multidisciplinary discussions involving oncologists, cardiologists, surgeons, and radiotherapists.

In the presence of an intracardiac thrombus, particularly in the context of embolic heart disease or a rhythm disorder such as atrial fibrillation, MRI can unequivocally confirm the thrombotic nature of the mass. This confirmation is crucial to avoid unnecessary surgery or to justify the initiation or continuation of anticoagulant treatment. In case of persistent diagnostic doubt, the MRI can be repeated after a few weeks of anticoagulant treatment to verify the regression or disappearance of the mass.

MRI is also used in infectious situations, particularly when a vegetation or abscess is suspected but difficult to characterize by echocardiography. It can then provide additional information useful for management, particularly in cases of suspected pericardial extension, myocardial abscess, or atypical intracardiac mass.

Thus, beyond its diagnostic role, MRI appears to be a major decision-making tool in therapeutic orientation, whether it concerns surgery, anticoagulation, oncological treatment or infectious management.

 

6. Limitations of MRI and prospects for development

Despite its many advantages, cardiac magnetic resonance imaging has certain limitations that should be taken into account in daily clinical practice.

Among the main constraints, absolute or relative contraindications constitute a significant obstacle. Patients with devices not compatible with the MRI environment (certain pacemakers or non-conditional defibrillators, ferromagnetic brain clips, implantable pumps) cannot benefit from the examination. In addition, patients with severe renal insufficiency (GFR < 30 mL / min/1.73 m²) cannot receive gadolinium due to the risk, although rare, of nephrogenic systemic fibrosis. These situations require the use of alternative techniques such as transesophageal ultrasound, cardiac CT or PET-CT depending on the context.

Technically, the quality of MRI can be affected by motion artifacts (poor apnea, irregular rhythm, tachycardia) or magnetic susceptibility artifacts (presence of metallic materials). Highly mobile masses can be difficult to characterize accurately, especially if ECG synchronization or apnea are not optimal. Similarly , very small volume lesions, particularly in an infectious context (valvular vegetations), can escape the spatial resolution of MRI, making transesophageal ultrasound superior in this specific setting.

Finally, access to cardiac MRI is not yet universal. It requires specialized expertise, adapted sequences, and expert reading, which can limit its use in facilities that lack trained teams or a suitable technical platform.

Nevertheless, there are many opportunities for development . The integration of advanced sequences such as T1 and T2 mapping , 4D flow imaging , or hybrid MRI-PET approaches promise to further refine tissue characterization and the detection of active tumor lesions. The use of specific or targeted contrasts , currently under development, could also improve the detection of tumor or inflammatory tissue. In the future, artificial intelligence could play an increasing role in automated mass detection, morphological analysis, and histological type prediction, particularly in complex or rare cases.

 

7. Conclusion

Cardiac MRI has established itself in recent years as an essential tool in the evaluation of intracardiac masses. With its unique ability to provide a detailed analysis of the morphology, dynamic behavior, and, above all, the tissue composition of masses, it not only allows for a more precise diagnosis but also for guiding therapeutic management with high reliability.

Its role is particularly decisive in the differentiation between tumor and thrombus, in the evaluation of the local extension of malignant tumors, as well as in the identification of pseudotumors or normal structures simulating a mass. In many cases, MRI makes it possible to avoid invasive procedures or to direct a targeted biopsy to a more accessible site. It is therefore an essential part of a multimodal and multidisciplinary approach to diagnosis.

Despite some technical or accessibility limitations, constant technological advances in cardiac MRI suggest an increasing role in the diagnostic strategy of intracardiac masses, with future applications in early detection, prognostic stratification and therapeutic monitoring.

In conclusion, cardiac MRI currently represents the most comprehensive modality for characterizing intracardiac masses, and it should be considered a reference examination in any diagnostic assessment of suspicious cardiac mass, in addition to other imaging techniques.

 

References

1.         Motwani M, Kidambi A, Herzog BA, et al. MRI in the evaluation of cardiac tumors: a review of current evidence. JACC Cardiovasc Imaging. 2014;7(10):896–905.

2.         Tyebally S, Chen D, Bhattacharyya S, et al. Cardiac tumors: JACC CardioOncology State-of-the-Art Review. JACC CardioOncol. 2020;2(2):293–311.

3.         Gulati G, Sharma S, Kothari SS, et al. Cardiac masses and tumors: a multimodality imaging approach from the Mayo Clinic. Radiographics. 2020;40(7):1910–1935.

4.         Hoey ETD, Shahid M, Ganeshan A, et al. Cardiac tumors: diagnosis and management. Clin Radiol. 2009;64(12):1212–1220.

5.         Randhawa K, Ganeshan A, Hoey ET. Magnetic resonance imaging of cardiac masses. Curr Probl Diagn Radiol. 2011;40(4):135–144.

6.         Araoz PA, Eklund HE, Welch TJ, Breen JF. CT and MR imaging of primary cardiac malignancies. Radiographics. 1999;19(6):1421–1434.

7.         Poterucha TJ, Kochav J, O’Connor DS, Rosner GF. Cardiac tumors: clinical presentation, diagnosis, and management. Curr Treat Options Cardiovasc Med. 2012;14(4):386–398.

8.      Grebenc ML, Rosado-de-Christenson ML, Green CE, et al. Primary cardiac and pericardial neoplasms: radiologic-pathologic correlation. Radiographics. 2000;20(4):1073–1103.

9.     Boxt LM. MR imaging of cardiac tumors and masses. Magn Reson Imaging Clin N Am. 2003;11(1):127–146.