Fatty lesions of the atria and interatrial septum

The value of multimodality imaging in diagnosis and treatment of cardiac lipoma

Background

Cardiac lipoma is a rare primary tumor in the heart and pericardium. Multimodality imaging methods, especially magnetic resonance imaging (MRI), are crucial in detecting and diagnosing cardiac lipomas. Besides, they are of significant importance in management of cardiac lipomas. The aim of this study was to evaluate the value of multimodality imaging methods in diagnosing and treatment of cardiac lipoma by describing a series of cases of cardiac lipoma.

Materials and methods

Data of patients with cardiac lipoma at a local institution were retrospectively collected. Their imaging findings on echocardiography, computed tomography (CT), and cardiac MRI and clinical management were described in detail.

Results

12 patients with cardiac lipoma were retrospectively included with thirteen lipomas found within heart and pericardium. Two patients’ lipoma were symptomatic, while lipomas in other 10 patients were found incidentally. Most lipomas were sensitively detected with echocardiography. Accurate diagnoses were achieved with CT and MRI in all cases. Surgical resection was performed in one symptomatic patient due to the obstruction of the left ventricular outflow tract, while the removal of pericardial lipoma in another symptomatic patient was not possible due to diffuse myocardial infiltration observed in MRI. Based on MRI findings, two patients without clinical symptoms also underwent surgery to prevent the risk of detachment of ventricular lipoma with a narrow pedicle in one patient and potential further thinning of the myocardium by pericardial lipoma growth in another patient.

Conclusions

Cardiac lipoma could be sensitively detected and accurately diagnosed with multiple noninvasive imaging tools. Comprehensive evaluation with multimodality imaging methods should also be conducted for better management planning and follow-up in all patients.

Lipomatous hypertrophy of the interatrial septum is a pathologic, not an anatomic diagnosis

BACKGROUND AND AIM

Lipomatous hypertrophy of the interatrial septum (LHIS), a fatty tumor, is usually diagnosed on both echo and CT/MRI imaging. Cases of LHIS located outside of the interatrial septum are extremely rare and rarer still are these cases large enough to cause symptoms. The clinical literature demonstrates a misunderstanding that fatty tumors outside the intra-atrial area represent lipomas. However, pathologic understanding of these fatty tumors is clear and is based on microscopic findings.

METHODS

The tumor was removed by diving the base of attachment at the left ventricular apex via a median sternotomy on cardiopulmonary bypass.

RESULTS

The patient made an uneventful recovery and remains well at 6 months postoperatively.

CONCLUSIONS

On rare occasions, LHIS can arise from outside the interatrial septum. An LHIS can be differentiated from a lipoma by the presence of entrapped cardiac myocytes in LHIS, making it a pathological, rather than an anatomic, diagnosis.

Fibrolipoma of the left ventricle: an uncommon incidental autopsy finding

Fibrolipoma of the heart is an unusual benign tumorous entity encountered, if present, during an ordinary imaging workout or at autopsy. It is often clinically silent but it can also be symptomatic depending on the size and location of the tumor. We report a case of an 82-year-old man with a medical history of malignant pleural mesothelioma. The decedent was referred to our department to undergo a forensic autopsy after a fall. Postmortem examination revealed a large encapsulated gelatinous, yellowish cardiac mass with its pedicle on the subendocardial region of the left ventricular anterior wall and interventricular septum, protruding into the left ventricular cavity. Histological examination confirmed the diagnosis of cardiac fibro-lipoma, a rare histologic variant of lipoma, irrelevant to the cause of death in the present case. The rarity of the occurrence of fibro-lipomas provides clinical implications for the inclusion of the entity in the differential diagnosis of a cardiac mass.

Approach to Surgery for Cardiac Tumors: Primary Simple, Primary Complex, and Secondary

Cardiac tumors are rare. Most surgeons will encounter few primary cardiac tumors outside of myxomas. This article offers the authors' approach to simple and complex primary and secondary cardiac tumors. Symptoms of primary cardiac tumors are primarily determined by tumor size and anatomic location. Most simple primary tumors and some complex primary tumors are best managed by surgical resection. Secondary tumors are 30 times more frequent than primary cardiac tumors. Surgical resection of secondary tumors is rational in a few highly selected patients. For complex primary and secondary tumors, the authors recommend referral to an experienced multidisciplinary cardiac tumor team.

Surgery for Tumors of the Heart

Most surgeons will encounter only a handful of primary cardiac tumors outside of myxomas. Approximately 3 quarters of primary cardiac tumors are benign and 1 quarter is malignant. In most cases, cardiac tumors are silent but when symptoms do occur, they are primarily determined by tumor size and anatomical location, not by histopathology. The diagnosis and preoperative imaging relies heavily on multimodal imaging including echocardiography, computed tomography, magnetic resonance imaging, and coronary angiography. Surgical resection is the most common treatment for most simple primary cardiac tumors and for some complex benign tumors. Surgical resection of primary cardiac tumors frequently involves the need for complex cardiac reconstruction, particularly when malignant. Secondary tumors to the heart are 30 times more frequent than primary cardiac tumors, and their incidence is increasing, largely as a result of advances in cancer diagnosis and therapy. Surgical resection is feasible in only a small fraction of highly-selected patients with secondary tumors to the heart. For complex benign tumors-such as paraganglioma or large fibromas-and all primary and secondary malignant tumors, a multidisciplinary cardiac tumor team review in experienced centers of excellence is recommended.

Normal Variants in Echocardiography

Echocardiography is a powerful and convenient tool used routinely in the cardiac evaluation of many patients. Improved resolution and visualization of cardiac anatomy has led to the discovery of many normal variant structures that have no known pathologic consequence. Importantly, these findings may masquerade as pathology prompting unnecessary further evaluation at the expense of anxiety, cost, or potential harm. This review provides an updated and comprehensive collection of normal anatomic variants on both transthoracic and transesophageal imaging.

Benign lipomatous masses of the heart: a comprehensive series of 47 cases with cytogenetic evaluation

Benign lipomatous lesions of the heart encompass an apparently etiologically diverse group of entities including neoplastic, congenital, and reparative phenomena. Among these, lipomas and lipomatous hypertrophy of the atrial septum (LHAS) represent 2 commonly encountered mass lesions. To date, no study has systematically and comparatively evaluated the morphologic and genetic characteristics of these lesions. Tissue registry archives of Mayo Clinic were queried for cases of cardiac lipoma and LHAS (1994-2011). Clinical, imaging, and pathologic findings were reviewed. Representative cases in each cohort were evaluated by fluorescence in situ hybridization (FISH) for HMGA1 and HMGA2 loci rearrangement and for MDM2/CPM locus amplification. Five cases of cardiac lipoma were identified (mean age, 67 years; range, 48-101; 3 men): 4 right atrial and 1 left ventricular. Forty-two cases of LHAS were identified (mean age, 75.6 years; range 45-95; 20 men), 39 of which were autopsy derived. The median size was 3.4 cm for lipomas and 2.8 cm for LHAS (n = 14). A single case each of cardiac lipoma and LHAS were found to harbor HMGA2 rearrangement, whereas no case showed cytogenetic abnormality of HMGA1 or CPM. This represents the largest series of histopathologically confirmed cardiac lipomas from a single institution. In addition, it is the first to evaluate cardiac lipomas and LHAS for genetic alterations associated with extracardiac lipomatous lesions. The genetic and morphologic similarities found provide evidence in support of the neoplastic classification of cardiac lipomas. A single case of LHAS contained an HMGA2 rearrangement, challenging the currently accepted hypothesis of pathogenesis for this lesion.

Fatty foci within the heart diagnosed with ECG-gated multi-slice computed tomography: frequency and morphology

BACKGROUND

The purpose of our study was to analyze the frequency of focal fatty replacement (FR) of the heart, as well as the distribution and detailed morphology of FR in a large group of patients referred to multi-slice computed tomography with ECG-gating examinations (ECG-MSCT) for various clinical reasons.

MATERIAL AND METHODS

The ECG-MSCT examinations of 1830 consecutive patients were analyzed. The examinations were performed using 8-row (1015 patients) and 64-row (815 patients) MSCT, in pre- and post-contrast scanning. We analyzed the morphology of FR, the dimensions and densities of changes, as well as the morphology and localization of FR with regard to clinical diagnosis.

RESULTS

204 subjects (11.1%) had FR within the heart (113 men; 91 women; mean age 57.8 years); 66% of fatty foci were seen only in the native scanning. The distribution of the fat was: right ventricle (RV) 31.9%, left ventricle (LV) 21.5%, biventricular 39.7%, interventricular or atrial septum 5.9%, and atria 1%. In the RV, fat was localized mainly in the papillary muscles, while in the LV fat was mainly subendocardial (p<0.001). The morphology of the fat was: linear 61.6%, oval 14.8%, punctuate 10.6%, irregular 10.2%, and bilobular 2.8%. Fat was primarily located subendocardially in the LV in patients after myocardial infarction. In patients with suspected coronary artery disease, it was mainly observed subpericardially in the RV and in papillary muscles (p<0.001).

CONCLUSIONS

The incidental frequency of FR within the heart in patients diagnosed with the ECG-MSCT examinations is about 11%. Pre-contrast scanning is the most valuable for FR assessment.

Anatomic variants mimicking pathology on echocardiography: differential diagnosis

Differentiation of normal from abnormal findings is critical in echocardiography. Anatomic variants occurring in normal cardiac developments often simulate pathologic entities. This review focuses on the differential diagnosis of normal anatomic structures from pathologic ones in echocardiography.

Primary cardiac tumours in the paediatric population

Primary cardiac tumours are relatively rare in the paediatric population, and they may occur with different signs and symptoms in foetal or post-natal life. The clinical manifestations of cardiac tumours in foetal life may include arrhythmias, congestive heart failure and hydrops. In post-natal life, cardiac tumours may cause cyanosis, respiratory distress, myocardial dysfunction, valvular insufficiency, arrhythmias, inflow or outflow tract obstructions and sudden death. Surgical treatment is essential when symptoms are present, while the role of medical therapy can merely be palliative. Results are various and related to the patients' and tumour characteristics. Primary benign heart tumours mainly have a good prognosis, while malignant neoplasms usually have a poor prognosis; in both cases, however, a strict follow-up is always mandatory in order to detect the recurrence of cardiac neoplasms after surgery.

Lipomatous hypertrophy of the interatrial septum in ECG-gated multislice computed tomography of the heart

BACKGROUND

Lipomatous hypertrophy of the interatrial septum (LHIS) is a benign disorder characterized by fat accumulation in the interatrial septum (IAS). The purpose of the study was to analyze the incidental detection of LHIS in patients with various clinical conditions, referred to ECG-gated multislice computed tomography (ECG-MSCT) examinations of the heart.

MATERIAL/METHODS

The ECG-MSCT examinations of 5786 patients (2839 women; 2947 men), were analyzed. The examinations were performed using 8-row (1015 patients) and 64-row (4771 patients) MSCT, in pre- and postcontrast scanning. We analyzed the shape of the IAS, density and maximal thickness of IAS, the thickness of the epicardial adipose tissue, and the degree of contact of IAS with the ascending aorta and superior vena cava. We also determined body mass index (BMI) in patients with LHIS.

RESULTS

LHIS was detected in 56 (0.96%) patients, with an average age of 61.5±9.8 years. The mean BMI in the analyzed group was 30.1±4.86. During the end-diastolic phase the thickness of IAS was significantly higher (p<0.0001), and on average equaled 18.3 mm. The mean optical density of the IAS was conspicuously higher (p<0.0001) in post-contrast phase than in pre-contrast phase. The thickness of the epicardial adipose tissue in the region of the left atrioventricular groove was on average 15 mm. In all cases the dumbbell shape of IAS was observed.

CONCLUSIONS

The incidental frequency of LHIS occurrence in patients diagnosed with the ECG-MSCT examinations is about 1%. In most subjects it is linked with a higher BMI and increased thickness of the epicardial adipose tissue.

Lipomatous hypertrophy of the interatrial septum: report of two cases where histological examination and surgical intervention were unavoidable

Lipomatous hypertrophy of the interatrial septum (LHIS) is an increasingly recognized heart condition characterized by fatty deposits in the interatrial septum with sparing of the fossa ovalis. Its distinctive characteristic features by imaging techniques, benign nature, and the fact that most patients remain asymptomatic, has limited the need for histological confirmation and operative intervention in most cases. In this report, we describe two cases of LHIS where cardiac surgical intervention was indispensable: in the first patient, due to the presence of an additional left atrial tumour found out as mixoma and in the second, to relief a superior vena cava obstruction together with bypass grafts for severe coronary artery disease. Histological samples of the interatrial septal lesion were obtained in both cases either because of uncertainty of the diagnosis (Case 1) or to confirm the diagnosis (Case 2).

Lipoma of the right atrium

A 66-year-old asymptomatic woman was admitted to our hospital with the diagnosis of a right atrial mass detected on an outside transthoracic echocardiogram and confirmed on transesophageal echocardiography. Physical examination and basal electrocardiogram were normal. Transthoracic echocardiography revealed a 3.8 x 2.5 cm echogenic mass in the right atrium. A multislice CT examination demonstrated a right atrial mass with a fat density ranging from -80 to -110 HU. The patient had a successful surgical excision of the mass, and the diagnosis of lipoma was confirmed on histopathological examination.