Cardiac Tumors & Masses

Moderator Band AKA:

Septomarginal Trabecula

Moderator Band (Septomarginal Trabecula)

• thick bundle of muscle traversing the RV

• variable size

• often verifies RV in fetal scanning

  • seen in lower 1/3

    • more toward apex

• not always visualized

• may act as a protective mechanism to resist RV overdistension

Normal Variants:

• Prominent RV Trabeculations

  • enhanced by RVH

• atrial appendage lined w/ pectinate m

• Ridge of Marshall

Ridge of Marshall AKA:

• Coumadin Ridge

• Warfarin Ridge

Ridge of Marshall

• tissue separating LAA and LUPV

• may be confused w/ clot

Fat

• can be found anywhere in heart

  • appears echogenic

Epicardial Fat Pad

• often located anteriorly

• sandwiched between epicardium and myocardium

  • seen PLAX if anterior

• appears anechoic in this location

  • can mimic loculated pericardial effusion

Eustachian Valve

• a membranous, endocardial tissue flap

• located at opening of the IVC into RA

  • may produce flow obstruction

    • IVC may become dilated

• needs to be determined from pathological mass / tumor

Eustachian Valve during fetal circulation:

• directs blood from RA to PFO (patent foramen ovale)

• serves no significant purpose in adult

Thebesian Valve

• a flap of endocardial tissue that guards the Coronary Sinus opening into the RA

• often continuous w/ the Eustachian valve

• not typically referenced in clinical practice

Chiari Network

• a freely mobile, lace/mesh-like membrane

  • located in RA near orifice of coronary sinus

• embryonic remnant

  • similar to Eustachian

• seen in 2-3% of the pop

• needs to be DDX’d from mass or tumor

LV Bands or False Tendons

• traverse the LV cavity

  • may be multiple

• seen in any view of the LV

• if prominent can produce confusing echos

• clinical significance is unknown

• rarely produce symptoms

What are other DDx’s for cardiac tumors / masses?

• MAC

• calcified papillary muscles

• artifacts:

  • near field gain

  • main bang

  • side lobes

Cardiac Tumor Categories:

• Primary

• Metastatic / Secondary

Primary Cardiac Tumors

• originate w/in the heart

• classified as:

  • benign (75%)

  • malignant (25%)

Metastatic / Secondary Cardiac Tumors

• originate from a primary malignancy located somewhere else in the body

• more common than primary tumors

Types of Primary Benign Cardiac Tumors:

• Myxoma

  • 50% of primary benign tumors

• Papilloma / Papillary Fibroelastoma

  • 10%

• Lipoma

  • 10%

• Fibroma

  • 4% of primary benign tumors

• Rhabdomyoma

What is the most common benign tumor of the adult population?

Myxoma

What is the most common benign tumor found in children?

Rhabdomyoma

Myxoma

• neoplasm that arises from endocardial tissue

  • 80% located in LA

  • RA 2nd most common

• usually attached by a stalk to the IAS

  • “pedunculated”

  • often arises from IAS

    • near region of fossa ovalis

Where might a Myxoma originate at?

• atrial appendage

• origin of a pulmonary vein

Myxoma characteristics:

• polypoid mass of gelatinous tissue

• tumor is usually mobile + moves w/ blood flow

Classic LA Myxoma

• echogenic mass located in the body of the LA in systole and prolapses through the mitral orifice in diastole

  • causes stenosis if large enough

    • narrowing of orifice

    • mimics MS

Potential risks of a Myxoma include:

• pt’s are at high risk for embolization

  • systemic or pulmonary

• death

  • d/t obstruction of flow, arrhythmia, emboli

• tumor may re-occur

  • can grow back after surgical removal

    • if seed still remains

Myxoma symptoms:

• asymptomatic → small

• Systemic embolization

  • from possible tumor fragments

• MV / TV obstruction

  • from tumor’s prolapsing motion into valve during diastole

• CP

• Dyspnea / DOE

• Hemoptysis

• Pulm edema

• syncope

• weakness / fatigue

• cachexia

  • weight loss

Myxoma Auscultastion

New / acquired / “changing” cardiac murmur → tumor “plop”

Myxoma EKG findings:

• conduction disturbances

  • arrhythmias

  • a-fib

  • atrial flutter

  • bundle branch blocks

Myxoma m-mode findings:

• blunted E-point of MV

• reduced E-F slope

  • can mimic MS

• heavy band of echoes behind AMVL in diastole

What does a Myxoma most closely mimic?

MS

Myxoma 2D findings:

• visualization of myxoma

  • allows detection, location, + sizing

• exaggerated motion of myxoma

  • d/t prolapsing from LA into the LV

Myxoma Doppler findings:

• mimics valvular MS findings

• MR may be noted

What is a new method of Myxoma diagnosis?

• Myocardial Contrast Echocardiography

  • contrast agent injection directly into the CA’s

    • shows normal myocardial perfusion

  • a myxoma will light up d/t contrast perfusion

  • thrombus will not absorb contrast

Other methods of Myxoma diagnosis:

• coronary angiography

Myxoma Treatment:

• prompt surgical excision

• serial echocardiography to R/O reoccurrence after surgical removal

  • LA myxoma can reoccur if ‘seed’ is not removed

    • similar to a wart

• some pt’s given anti-coag’s + rescanned within 1 month

  • to differentiate from a thrombus

Papilloma / Papillary Fibroelastoma

• most common tumor of cardiac valves + valve apparatus

  • can arise from any endocardial surface

  • most common: AoV, MV, TV in children

• small, pedunculated benign tumor

  • attached by a single stalk

  • very mobile

• clinical significance is unclear

  • noted to be an emboli source d/t attracting platelets / fibrin

• DDx: Endocarditis & Lambl’s excrescence

Lipoma

• neoplasm of mature fat cells

• well-defined, homogenous, dense mass

• can invade all 3 heart layers

Types of Lipomas:

• Fibrolipomas

  • contain fibrous connective tissue component along w/ fat

• Myolipomas

  • contain muscular tissue along w/ fat

Where are Lipomas usually located?

• LV

• RA

• IAS

  • termed: Lipomatous Hypertrophy of IAS

Lipomatous Hypertrophy of IAS

• most common Lipoma location is IAS

• “Dumbell” shaped IAS

  • d/t IAS thickening w/ sparing of fossa ovalis

• may cause A-fib

• associated w/ steroid use

Fibroma

• most commonly arise from LV free wall or IVS

  • intramural

    • embedded in myocardium

  • can extend into chambers as they enlarge

  • does not invade the pericardium

    • malignant counterpart will → fibrosarcoma

Fibromas may cause:

• obstruction to LV inflow or outflow

  • associated w/ sudden death

• CHF

• arrhythmias

Characteristics of Fibromas include:

• isolated

• slow growing

• un-capsulated

• well-circumscribed

• highly echogenic

Rhabdomyoma

• found at birth and <1 yr

• 70-90% have multiple tumors

• associated w/ tuberous sclerosis

• found in ventricular walls

  • more common in RV

  • solid, echo-dense mass protruding into ventricular cavity

• mortality d/t blood flow obstruction

• have been reported to recede over time

What is the most common tumor found in children?

Rhabdomyoma

Other primary benign heart tumors include:

• hemangioma

• teratoma

Hemangioma

• vascular tumor

• located in any chamber

  • right heart > lt

Teratoma

• composed of skeletal, nerve, connective tissues

  • teeth, hair, skeletal components may be found

• located in RA, RV, + septum

Angiosarcoma

• RA location 80%

• most common primary malignant tumor of the heart

• may cause inflow obstruction

• associated w/ pericardial effusion

Angiosarcoma note:

• applies to a wide range of malignant endothelial vascular neoplasms that affect a variety of sites

  • skin, liver, bone, breast, spleen, heart

Other Primary Malignant Intracardiac Tumors in order of MOST to least common:

1. Rhabdomyosarcoma

2. Mesothelioma

3. Fibrosarcoma

4. Osteosarcoma

Mesothelioma

• malignant intracardiac tumor d/t asbestos exposure

• occur in pericardium of heart, but most commonly found in pleural lining (lungs)

Metastatic / Secondary Intracardiac Tumors

• pericardial > myocardial involvement

  • pericardial effusion

    • often the 1st indication

  • heart invaded by:

    • malignancy of breast or lung

    • sarcoma

    • melanoma

    • lymphoma (can also invade myocardium)

    • Renal, Liver, Wilm’s tumors

  • extend from IVC to RA (1st) and RV (2nd)

    • rarely affects LV function

What extracardiac tumors may compress cardiac structures?

• mediastinal tumors/cysts

  • thymus

  • lymphoma

• pericardial tumors/cysts

• pleural tumor

• hematoma

• teratoma

• pancreatic cyst

• diaphragmatic hernia