Multimodal Imaging Guides Prophylactic Surgery for Extensive Left Ventricular Lipoma

Multimodal imaging confirmed a rare, extensive left ventricular lipoma that occupied nearly the entire ventricular cavity and involved the papillary muscles, guiding proactive surgical resection in an asymptomatic patient despite standard guideline recommendations for conservative observation.

The mass was discovered incidentally in a 32-year-old male during routine preoperative evaluation for kidney stones at a local medical center. His baseline medical history and physical examination showed no abnormal signs, and a standard twelve-lead surface electrocardiogram demonstrated normal cardiac conduction without pathological changes.

Upon admission, transthoracic echocardiography revealed two distinct irregular, hyperechoic, broad-based, and immobile masses situated within different segments of the left ventricle. The first mass, designated M1, arose from the basal segment of the inferoseptal wall, measuring 4.6 by 1.8 centimeters with a 3.9-centimeter base, and its superior margin approached within approximately 0.3 centimeters of the anterior mitral leaflet annulus. The second mass, designated M2, exhibited punctate hyperechoic microcalcifications and was attached along the middle and apical segments of the inferolateral and inferior walls, measuring 3.9 by 3.6 centimeters with a 3.5-centimeter base, while color Doppler interrogation confirmed that neither ventricular inflow, outflow, nor the lumen suffered hemodynamic obstruction.

To assess the internal structure and vascularity of the lesions, clinicians initiated contrast echocardiography. Left ventricular opacification demonstrated an absence of contrast agent filling within the internal bodies of the masses. Myocardial contrast echocardiography was subsequently conducted using 2.5 milliliters of SonoVue contrast agent administered at a steady rate through the left cubital vein over two minutes, followed by a three-milliliter normal saline flush. Sequential imaging of the right and left heart revealed slight contrast enhancement at the attachment bases, demonstrating an unclear tissue boundary between the tumor margins and the underlying myocardium.

Additional non-invasive imaging techniques corroborated the echocardiographic findings and refined the tissue diagnosis. Cardiac magnetic resonance imaging showed homogeneous signals consistent with adipose tissue across all evaluated pulse sequences. In addition, 18F-fluorodeoxyglucose positron emission tomography combined with computed tomography revealed no abnormal metabolic uptake, ruling out high metabolic activity and confirming a benign adipose lesion corresponding directly with ultrasound observations.

Although cardiac lipomas represent the second most common primary benign cardiac tumor, accounting for eight to twelve percent of cases, clinical guidelines typically advise conservative non-surgical monitoring when patients remain asymptomatic. However, clinicians opted for surgical intervention because extensive ventricular tumors carry substantial risks of future complications. Growth of the mass could induce malignant ventricular arrhythmias due to proximity to conduction pathways, trigger left ventricular outflow tract obstruction, or cause progressive mechanical compression leading to left ventricular aneurysms or sudden cardiac death.

To prevent these adverse outcomes while minimizing surgical trauma, surgeons performed a targeted resection through a small aortic incision. The surgical team removed the majority of the soft tissue adhering to the interventricular septum and papillary muscles, successfully reducing the potential for hemodynamic disturbances across the mitral valve orifice and ventricular outflow tract. Complete tumor extirpation was technically impossible because preoperative myocardial contrast echocardiography had revealed that portions of the tumor were integrated with and partly immersed within the interventricular septum.

Intraoperative monitoring with transesophageal echocardiography confirmed a residual, slightly hyperechoic mass located near the apical segment of the left ventricular inferolateral wall. Complementary real-time three-dimensional transesophageal echocardiography supplied detailed anatomical visualization of the remaining tissue. Postoperative histopathological examination of the resected tissue demonstrated mature adipose cells without evidence of cellular infiltration or malignancy, validating the preoperative imaging diagnosis.

The case underscores the technical utility of contrast echocardiography and three-dimensional imaging in cardiac mass evaluation. Contrast echocardiography provides real-time visualization of microvascular perfusion patterns, helping clinicians differentiate hypervascular malignant lesions from hypovascular or avascular benign masses such as myxomas, lipomas, or thrombi. Because the technique is non-invasive, avoids ionizing radiation, and does not require nephrotoxic contrast agents, it offers a practical alternative for patients with renal impairment who cannot undergo contrast-enhanced magnetic resonance imaging. Furthermore, three-dimensional echocardiography generates volumetric datasets and surface reconstructions that aid in clarifying spatial relationships with adjacent structures for surgical navigation.

Beyond initial surgical planning, contrast echocardiography serves as an effective modality for long-term postoperative surveillance. By identifying neovascularization, contrast enhancement allows clinicians to distinguish vascularized residual or recurrent tumor tissue from avascular postoperative scars or thrombotic formations. The authors concluded that integrated multimodal imaging provides indispensable information across the entire clinical continuum, from establishing an accurate initial diagnosis to formulating individualized surgical strategies and conducting ongoing post-resection monitoring.

Transthoracic echocardiography served as the primary first-line modality following the incidental detection of left ventricular masses during preoperative examination for kidney stones in an asymptomatic thirty-two-year-old male. Baseline medical history, physical examination, and twelve-lead surface electrocardiography were entirely normal. Non-standard transthoracic views revealed two irregular, broad-based, immobile, hyperechoic masses occupying distinct ventricular regions. The first lesion, designated M1, arose from the basal inferoseptal wall, measuring 4.6 by 1.8 centimeters with a 3.9-centimeter base, its superior attachment terminating approximately 0.3 centimeters from the anterior mitral leaflet annulus. The second lesion, designated M2, was attached to middle and apical segments of inferolateral and inferior walls, measuring 3.9 by 3.6 centimeters with a 3.5-centimeter base and displaying punctate hyperechoic microcalcifications. Color Doppler interrogation confirmed that neither ventricular inflow, outflow, nor the intracavitary lumen experienced hemodynamic obstruction despite the significant mass dimensions.

To clarify tumor vascularity and structural composition, clinicians conducted contrast-enhanced echocardiography to exclude hypervascular malignancies and avascular thrombi. Left ventricular opacification initially revealed complete absence of contrast filling within the masses. Clinicians subsequently performed myocardial contrast echocardiography by administering 2.5 milliliters of SonoVue contrast agent via the left cubital vein at a constant infusion rate over two minutes, followed by a three-milliliter normal saline flush. Sequential opacification of the right and left heart chambers demonstrated slight contrast enhancement at the attachment bases of both masses, indicating an unclear boundary with the underlying myocardium. This precise perfusion pattern matched the histological features of cardiac lipoma, allowing the medical team to eliminate other benign neoplasms and confirm that the tumor margins merged directly into myocardial tissue.

Cross-sectional multimodal imaging supplied further soft-tissue characterization that corroborated the echocardiographic assessment. Cardiac magnetic resonance imaging exhibited homogeneous signals identical to fat across all pulse sequences, confirming uniform adipose composition without suspicious heterogeneity. Concurrently, fluorine-18 fluorodeoxyglucose positron emission tomography showed an absence of abnormal metabolic uptake, verifying that the masses lacked malignant or inflammatory activity. These cross-sectional imaging modalities substantiated the echocardiographic findings and reinforced diagnostic certainty. By capturing detailed soft-tissue features that corresponded directly with ultrasound observations, multimodal evaluation eliminated diagnostic ambiguity. The comprehensive alignment between echocardiography, magnetic resonance imaging, and positron emission tomography established the definitive presence of an extensive, benign left ventricular lipoma prior to invasive intervention.

The surgical strategy diverged from conventional guideline recommendations, which generally endorse conservative management for asymptomatic cardiac lipomas because of their benign pathology. Although lipomas represent the second most frequent primary benign cardiac tumor, comprising eight to twelve percent of primary cardiac neoplasms, conservative management was considered inappropriate due to the extraordinary size and critical anatomical involvement in this patient. The tumor occupied nearly the entire left ventricular cavity and enveloped the papillary muscles. The clinical team recognized that untreated lesions could enlarge over time, precipitating severe hemodynamic and electrophysiological complications. Proximity to specialized conduction pathways posed a risk of malignant ventricular arrhythmias, while mass impingement on ventricular outflow pathways could generate progressive outflow obstruction. Additionally, persistent mechanical compression against the myocardium risked causing left ventricular aneurysms or irreversible structural compromise, justifying proactive resection to prevent sudden cardiac death.

To mitigate operative trauma and prevent intraoperative cardiac injury, surgeons accessed the tumor through a small aortic incision. The surgical intervention focused on resecting the majority of the soft tissue adhering to the interventricular septum and papillary muscles, successfully reducing future hemodynamic risks across the mitral valve orifice, ventricular inflow, and ventricular outflow tract. Complete tumor removal proved unfeasible because preoperative myocardial contrast echocardiography had revealed that portions of the neoplasm were integrated with and partly immersed within the interventricular septum. Intraoperative transesophageal echocardiography confirmed a residual, slightly hyperechoic mass near the apical segment of the inferolateral wall, while real-time three-dimensional transesophageal imaging provided detailed spatial confirmation of the remaining cardiac architecture. Postoperative histological evaluation validated the preoperative diagnostic conclusions, demonstrating mature adipose tissue without malignant transformation or invasive cellular infiltration.

The surgical outcome and ongoing management reflect broader prognostic considerations documented in cardiac tumor literature, which associates incomplete surgical resection and postoperative ventricular arrhythmias with increased postoperative mortality in ventricular lipoma cases. Given the planned incomplete resection, longitudinal monitoring plays a decisive role in patient safety. Contrast echocardiography provides dynamic, real-time assessment of tissue vascularity and microperfusion at low cost and without ionizing radiation, making it exceptionally advantageous for bedside evaluation and for patients with renal impairment who cannot receive magnetic resonance contrast agents. Concurrently, three-dimensional echocardiography offers volumetric datasets and surface reconstructions that aid in clarifying spatial morphology. In postoperative follow-up, contrast echocardiography enables clinicians to distinguish avascular scars or thrombotic formations from vascularized residual tissue or recurrent tumor neovasculature. The authors concluded that integrated multimodal imaging provides indispensable clinical value across perioperative decision-making and dynamic postoperative monitoring, while reporting that no datasets were generated or analyzed during the study.

Subject of Research: Multimodal imaging and surgical intervention for left ventricular lipoma

Article Title: Diagnostic characteristics of multimodality imaging for left ventricular lipoma: new insights on surgical intervention

Article References: Liu, T., Fang, L., Shi, J., He, L., Zhang, J., Li, Y., Xie, M., & Wang, J. (2025). Diagnostic characteristics of multimodality imaging for left ventricular lipoma: new insights on surgical intervention. Cardiovascular Ultrasound, 23(1), Article 11. https://doi.org/10.1186/s12947-025-00346-2

Image Credits: AI Generated

DOI: 10.1186/s12947-025-00346-2

Keywords: left ventricular lipoma, multimodal imaging, transthoracic echocardiography, contrast-enhanced echocardiography, myocardial contrast echocardiography, left ventricular opacification, cardiac magnetic resonance imaging, positron emission tomography, prophylactic surgical resection, interventricular septum, papillary muscles, transesophageal echocardiography, three-dimensional echocardiography, cardiac neoplasms, SonoVue, hemodynamic obstruction, ventricular arrhythmia