CT AND MR IMAGING OFCARDIAC TUMORS

B.Zandi Professor of Radiology

Objectives

To review the Spectrum of CT and MRI findings for a variety of cardiac neoplasms.

The role of CT and MRI in : The Diagnosis of Cardiac Tumors To DD Benign from Malignant Masses. the use of MDCT in providing Anatomical Information MRI for Tissue Characterization of Cardiac Masses.

Cardiac tumors

Prevalence of 0.002-0.3% at Autopsy 1. Primary Cardiac Neoplasms (Benign and malignant) 2. Metastatic approximately 30 times more Prevalent than

primary

Imaging Modalities

Trans-thoracic Echocardiography Trans-esophageal Echocardiography Multi-detector CT Scanning (MDCT) Magnetic resonance imaging (MRI)

Imaging Modalities

Trans-thoracic Echocardiography : Most Widely Used imaging modality The Best Imaging modality to depict Small Masses

(Valves ) Limitations : Visualization of Extra-Cardiac Extension TEE : less limitation of acoustic window than

thoracic mode, The Airways and lungs can be obstacles for imaging

of the Aortic arch, Pulmonary Arteries and Veins

Imaging Modalities

MRI : The Modality of Choice to evaluate Cardiac Tumors. High Contrast Resolution and MPR allow : a Specific Diagnosis Optimal Evaluation of Myocardial infiltration, Pericardial involvement and Extra-Cardiac Extension.

Imaging Modalities

MDCT Scan : MDCT Recently, has been Increasingly Utilized for Cardiac Imaging. Short Image Acquisition Time compared to MRI ( an advantage in Cardiac

Imaging ) ECG Gating MDCT either by Scanning or Reconstructing Raw Data at the

point of the Least Cardiac Motion. CT has better Soft Tissue Contrast Resolution than Echo definitively characterize Fat and Calcifications Wide field-of-view helps : to assess the Extent of a Cardiac Malignancy and to detect Metastatic Lesions

Table 1. Primary Benign Tumors and Cysts of Heart andPericardium in 533 cases

Myxoma 130 (24.2) Lipoma 45 (8.4) Papillary Fibroelastoma 42 (7.9) Rhabdomyoma 36 (6.8) Fibroma 17 (3.2) Hemangioma 15 (2.8) Teratoma 14 (2.6) Mesotheloma of AV node 12 (2.3) Granular cell tumor 3 Neurofibroma 3 Lymphangioma 3 Subtotal 319 (59.8 Pericardial Cyst 82 (15.4) Bronchogenic Cyst 7 (1.3) Subtotal 89 (16.7)

Myxomas

the Most Common Benign Tumor (4th-7th decades) LOCATION : Inter-atrial Septum at fossa ovalis LA (Most Common ) 75% LA ( typically, in the Inter-atrial Septum ) 20% in RA , rarely in the Ventricles. Typical Morphologic Characteristics : Gelatinous, attached to

stalk, Calcification , Hemorrhage or Necrosis; Common

Imaging Characteristics

Echo Features : Mobile tumor, Narrow stalk CT Features : Well-defined Spherical or Ovoid Intra-Cavitary Mass

with Heterogeneous, low attenuation, Typically Lobular Contours IV-CT : Heterogeneous (Hemorrhage, Necrosis, Cyst formation,

Fibrosis or Calcification) MR Imaging Features : Heterogeneous (before contrast) Heterogeneous Enhancement (after contrast) areas of Low signal intensity within the tumor (due to Calcification or

Hemosiderin ). T2W : Markedly High Signal

LV Myxoma in 38-year-old female.A. Mass (arrow) in LA. B. Mass (arrow) extends into LV during diastolic phase through mitral valve.

MPR MDCT 4-chamber view

LA Myxoma in 65-year-old male. A. shows LA mass attached to inter-atrial septum by broad pedicle Strong Enhancement in part of mass with foci of Calcification B. Gross specimen : Multicolor Soft Tissue Mass ( mixture of Hemorrhage,

Necrosis, Cyst formation and Fibrosis )

MPR MDCT

RV Myxoma in 30-year-old female. A. Isointense mass occupying RVOT B. High Signal Intensity in most parts of mass C. Hyperenhancement of mass D. Yellow Soft Tissue Mass with narrow base of attachment to RV.

MRI-DIR MRI-TIR MRI- Gd-DIR

RV myxoma in a 55-year-old man. a mass prolapsing into the main PA .

short-axis view systole

Lipomas

The Second Most Common Benign Cardiac Tumors in adults. Age : Variabale Associated Syndromes : Tuberous Sclerosis (few cases) Location : Pericardial Space or any Cardiac Chamber Typical Morphologic Characteristics : Very large, Broad-based; no Calcification,

Hemorrhage, or Necrosis Echo : Usually Hypoechoic in the Pericardial Space, Echogenic in a cardiac

Chamber Specific CT and MR imaging Characteristics. CT : Homogeneous, low-attenuation mass MRI : Homogeneous High Signal intensity on the T1/T2 that decreases with the use of Fat-Sat sequences. do not show Contrast enhancement

RA lipoma in 62-year-old female. A. Homogeneously low-attenuated mass with pedicle (arrow) attached to free wall of RA B. Gross specimen : shows fatty nature of mass.

ECG-g MDCT

RA lipoma in a 72- year-old man. A . large mass (M) arising from the postero-lateral wall of the RA B . Circumscribed, broad-based mass , High Signal fills most of the RA. C . Smooth lipoma filling the RA.

apical 4ch view T1W MRIntra-operative photograph

Lipomatous Hypertrophy of the inter-atrial septum /35-year-old woman with AF . sparing the adjacent Fossa Ovalis, favouring the diagnosis of lipomatous hypertrophy

rather than lipoma.

4ch, T2 BB T1 BB

fat-suppressed, T2 delayed 10 min

Fatty infiltration of the inter-atrial septum in a 69-year-old, mildly obese woman with palpitations, dyspnea, and an atrial tachyarrhythmia.

wedge-shaped fatty thickening of the inter-atrial septum (arrows). extension of fatty tissue into the RV (arrowhead).

Papillary Fibroelastomas

Are Benign Endocardial Papillomas Age : Middle-age Typical Morphologic Characteristics : Small (<1.5 cm) frond- like, narrow

stalk mass attached to the Moving Valves ; Calcification rare, no Hemorrhage or Necrosis

Location : Cardiac Valves 75% of all Cardiac Valvular tumors . Echo : small masses with “Shimmering” edges CT and MR Features : Usually not seen MRI : Typically a mass on a Valve Leaflet or on the Endocardial surface Cine MR : Turbulence in the blood flow.

Papillary Fibroelastoma of AO Valve in 60-year-old female. A : abnormal Thickening of AO Valve (arrow). B, C : small mass (arrows) attached to Aortic Valve ( moving according to valvular motion ). D : slightly high signal intensity of small mass (arrow).

ECG-gated MDCT cine MR Oblique TIR MR

Rhabdomyomas

the Most Common Cardiac Tumors in Infancy and Childhood, Associated Syndromes : Tuberous Sclerosis in up to 50% of

cases Mostly Asymptomatic and generally regress spontaneously. Location : Typically in the Myocardium of Ventricles, and

multiple lesions up to 90% of cases. MRI : T1W ; Isointense to marginally Hyperintense T2W ; Hyperintense

Cardiac Rhabdomyoma in Newborn with Tuberous Sclerosis. A. Nodules in Caudate Nuclei and Frontal Lobes B. Iso-Intense mass in Septum and anterior wall of LV. C. Mild Enhancement

Gd-E T1W Sagittal T1W SE MR Axial Gd-E T1W SE MR

Fibroma of the LV in a 32-year-old F, with recurrent syncope and runs of V Tach. (a,b,c) a well-defined, low-signal mass within the anterior wall of the LV. (d) uniform enhancement and a thin rim of surrounding compressed myocardium.

T1 T2

SSFP (WB) Delayed10 min

*

Table 1. Primary Malignant Tumors and Cysts of Heart and Pericardium in533 cases

Malignant Angiosarcoma 39 (7.3) Rhabdomyosarcoma 26 (4.9) Mesothelioma 19 (3.6) Fibrosarcoma 14 (2.6) Malignant Lymphoma 7 (1.3) Extraskeletal Osteosarcoma 5 Neurogenic Sarcoma 4 Malignant Teratoma 1 Thymoma 1 Leiomyosarcoma 1 Liposarcoma Synovial Sarcoma 1 Subtotal 125 (23.5)

Angiosarcomas

The Most Common Cardiac Sarcomas (37%) Location : RA and involves the Pericardium. Presentation : Rt-sided Heart Failure or Tamponade Late Presentation (often Metastases at the time of

diagnosis, particularly to the Lung ) Invasive behavior ( Pericardial or Pleural Effusion ).

Angiosarcomas

CT : a Low-Density Irregular or Nodular Mass in the RA Specific MR feature: (on T1/T2 ) a Heterogeneous Papillary

Appearance , with and Nodular areas of High Signal interspersed within areas of Intermediate Signal

Enhancement : Linear along the Vascular Spaces as a “Sunray”

Angiosarcoma of RA in 48- year-old male. A. large mass at the free wall of RA.(irregular and nodular contour and strong contrast

enhancement). B. mostly Isointense mass in RA. C. Heterogeneously Hyperintense mass . D. Heterogeneous Hyper-enhancement /areas of no enhancement (Intra-tumoral Thrombosis).

. ECG-gated MDCT DIR MR TIR MR

Gd-E DIR MR

Primary Cardiac Angiosarcoma in a 55-year-old man with Weight loss, Dyspnea, and Peripheral Edema.

A. a large, Heterogeneous, Isointense mass completely obliterates the RA. (areas of low and High signal , (due to hemorrhage , necrosis ).

T1W DIR FSE T2W DIR FSE

GdE T1W DIR FSE 4Ch SSFP

Primary cardiac angiosarcoma in a 25-year old woman : with leg swelling, abdominal pain, bloating, and dyspnea. A. a large Heterogeneous mass at the RA free wall. predominantly isointense ,

some areas of High-Signal (localized hemorrhage) B,C. large, Hyperintense, Water- rich mass, left pl eff

T1WSE echo-planar T2W DIR fast SE T2W DIR Fat-Supp

The influence of different MR SequencesPrimary Cardiac Angiosarcoma

Other Cardiac Sarcomas

Including : Undifferentiated Sarcomas Malignant Fibrous Histiocytomas (MFHs) Leiomyosarcomas Osteosarcomas Lymphosarcomas Myxosarcomas Neurogenic Sarcomas Synovial Sarcomas Neurofibrosarcomas Kaposi’s Sarcomaso Although most Angiosarcomas occur in the RA, the other sarcomas

affect the LA more frequently, (an important differentiating feature)

Rhabdomyosarcoma

is the Commonest Childhood Primary Cardiac Malignancy two distinct Histological Types: Embryonal types, occur in Children and Adults Pleomorphic , Much Less Frequent and occur in Adulthood Location : No Specific Chamber Valves involvement , is more likely than any other Primary

Cardiac Sarcoma Multiple sites of involvement

Rhabdomyosarcoma

The presentation: Depends on the area of involvement, but as the other Cardiac Sarcomas, CHF is common. MRI : T1W Iso-intense to myocardium Homogeneous Gd-enhancement Some areas of low Signal Intensity (Central Necrosis).

Rhabdomyosarcoma in 22 year old A,D. MDCT+IV : LA mas Extending through the septum to the RA B,C. T1 SE 6 months after resection , Recurrence at the septum and pericardial involvement

MDCT+IV

T1 SE

T1 SE

T1 SE

Fibrosarcoma CT 4 Chamber Involvement T1W 1 year later after therapy

Primary Cardiac Lymphomas

Extremely Rare, ( incidence of 0.15 to 1% ) Most Common Type : Diffuse Large B cell Mostly : Solid Infiltrative Tumors in one or multiple

chambers of the heart. Mimicking Classic HCM (massive infiltration of the

myocardium )

Primary Cardiac Lymphomas

CT : as Hypo- or Iso-attenuated Infiltration Enhancement : Heterogeneous MRI : T1W ; Isointense T2W ; Heterogeneously Hyperintense Gd-E ; Heterogeneous Enhancement

Primary Cardiac Lymphoma (diffuse large B-cell type) in 73-year-old male. A. Homogeneous infiltration at RA wall and inter-atrial septum. Pericardial effusion; (Pericardial invasion ?) B. Diffuse Infiltrative Mass in RA Homogeneous Enhancement (distinguishes it from pericardial eff)

Enh-MDCT Gd-E DIR MR

(a) A 35-year-old man with AIDS presented with dyspnoea. a large, solid mass filling the LA isointense with myocardium. (b) A 42-year-old F, no history of immunosuppression /with cardiac failure. Diffuse soft-tissue mass filling the pericardial space and the free wall of the RA

and LV

T1 BB SSFP (WB)

Primary cardiac lymphoma : different patterns of cardiac involvement.

Secondary Cardiac Lymphoma , bilateral Adrenal, renal and intera and retroperitoneal involvement.

Metastatic Involvement

Much More Common than Primary Tumors, Ratio of 30:1 Cardiac mets occur in 11% of cases of malignancies Most Frequent Malignancies to the heart : Lung , Breast, Melanomas and Lymphomas The Most Common site : Epicardium Spreading means : 1. mainly the Mediastinal Lymphatics to the Epicardial Surface 2. Hematogenously through the : Coronary arteries, or less commonly IVC 3. Direct Extension ( Thymic , Bronchial, Breast and Esophagus )

Metastatic Involvement

Commonly Coincidence Hematogenous Mets in other organs (Lungs).

Trans-Venous tumor spread : into the RA through the SVC (lung ) or IVC (kidney or liver) into the LA via the Pulmonary Veins. DD of Metastases from Thrombus : Enhancement Patterns after IV Gd-E: (Hetergenous Enh) IR Time 400-500msec

Intracardiac Metastases ( 20-year-old, Seminoma ; with dyspnoea and chest pain. MDCT : Several large low attenuation masses within the RV. the changes in both lungs, caused by multiple tumour emboli.

Hematogenous Cardiac Metastases from HCC A ,B . Marked Diffuse Thickening of RV free wall (arrows). C, D. HCC Characteristic pattern of early enhancement and wash out

MDCT Gd-e DIR MR

Arterial (C) and delayed (D) CT

Direct Venous Extension of a left-sided RCC LRV and IVC are filled by a isointense mass extending into the RA

Nonenhanced T1W SE echo-planar

Tumorlike Lesions

Thrombus is The commonest Mimic of a cardiac Neoplasms

Most likely to be located posteriorly in the LA,( AF , or severe LV Dysfunction)

It can also be found in the right side of the heart

Tumor-like Lesions (Thrombus)

MR Characteristics : Variable depending on the age of the thrombus.

Acute thrombus : Bright on both T1 and T2 Subacute thrombus : Bright on T1, and Low-Signal areas on T2 (the

Paramagnetic effects of Methemoglobin ) Chronic organized thrombus : T1/T2; Low Signal (Water depletion ,

with or without calcification ) Gd-E ; Useful for DD thrombus from tumors ( Thrombus doesn't

enhance) Long Inversion time (400 msec) Note : Organized Thrombus may show some surface Enhancement) DD : Slow or Static Flow / Flows through the imaging plane

Intracardiac Thrombus. (a) A 64-year-old man with a past history

of anterior wall myocardial infarction. non-enhanced mass (arrows) and an

overlying (high signal) full thickness MI. (b) A 55-year-old man with a prior history

of anterior myocardial infarction. a low-attenuation mass within the LV

delayed- 10 min + 500mSec IR

Vertical, long axis (2-ch) delayed 10 min ,long IR time(500 ms)

Flow artefact within the RV as a low attenuation filling defect ‘‘pseudotumour’’ IVC inflow

SSFP

Thrombus different locations

RCA Aneurysm. a smoothly marginated mass indenting the RV free wall.

Axial SSFP Coronal Gd-E First pass

T

CONCLUSION

CT and MRI may be useful in the DD of Benign/Malignant cardiac masses. CT is useful for the evaluation of Ca and Fat content within a mass The High Spatial Resolution of MDCT is beneficial to define Small Lesions MDCT is useful in the Staging of Malignant Tumors. The Excellent Contrast Resolution of MRI allows Characterization of

Fibromas and Hemangiomas. Homogeneity of a mass due to compact cellularity may be characteristic of

a Lymphoma. Acquisition of Post-Contrast Sequences enables better depiction of tumor

Vascularity and can be used to define Tumor Borders. MRI has an important role in DD Thrombi from Cardiac Tumors. MDCT and MRI might help determine Resectability of a Tumor and allow

planning for reconstruction of the cardiac chambers.