Cardiac masses are uncommon entities that can be broadly classified

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1 Dign Interv Rdiol 2012; 18:67 77 Turkish Society of Rdiology 2012 CARDIOVASCULAR IMAGING PICTORIAL ESSAY Crdic neoplsms nd pseudotumors: imging findings on multidetector CT ngiogrphy Edwrd Hoey, Arul Gneshn, Kurdow Nder, Kirn Rndhw, Richrd Wtkin ABSTRACT A wide spectrum of msses cn ffect the hert, rnging from non-mlignnt entities, such s thromi, to ggressive primry crdic tumors, such s ngiosrcoms. Echocrdiogrphy nd mgnetic resonnce imging hve trditionlly formed the minsty techniques for ssessing these lesions. Recent technologicl dvnces hve seen ECG-gted multi-detector computed tomogrphy (MDCT) emerge s vlule complimentry technique for ssessing suspected crdic mss ecuse it provides high sptil resolution, fst cquisition times, nd the ility to definitively chrcterize ft nd clcifiction. This rticle reviews the MDCT fetures of the spectrum of crdic neoplsms nd pseudotumors nd descries importnt dignostic criteri. Key words: computed tomogrphy ngiogrphy neoplsms hert From the Deprtments of Crdiovsculr Rdiology (E.H. [email protected], A.G., K.N., K.R.) nd Crdiology (R.W.), Hert of Englnd NHS Trust, Birminghm, West Midlnds, United Kingdom. Received 12 Jnury 2011; revision requested 14 Ferury 2011; revision received 6 My 2011; ccepted 7 My Pulished online 1 Novemer 2011 DOI / DIR Crdic msses re uncommon entities tht cn e rodly clssified s non-neoplstic or neoplstic. Some norml ntomicl structures (such s prominent crist terminlis) nd some nonneoplstic lesions (such s intrcvitry thromi) cn mimic true crdic neoplsm. Neoplstic msses re sudivided into metsttic, primry enign nd primry mlignnt tumors. Becuse most crdic msses re not menle to iopsy, non-invsive imging plys pivotl role in their evlution; imging is lso importnt if surgicl resection is contemplted ecuse ccurte delinetion of lesion s mrgins helps predict the likelihood of complete removl (1). A multi-modlity imging pproch is usully required when investigting suspected crdic mss, with the choice of imging technique guided y ptient-relted fctors, locl vilility, nd provider expertise. The primry gols of imging re the following: 1) to scertin if mss is present; 2) to define mss s loction, extent, nd reltionships; nd 3) to distinguish etween potentilly enign nd mlignnt lesions. Trnsthorcic echocrdiogrphy (TTE) is usully the initil imging technique nd is roust for identifying n intrcrdic mss, provided tht the coustic windows re dequte. In ptients with lrge ody hitus or emphysem, the evlution is frequently limited. Trnsesophgel echocrdiogrphy (TEE) ffords improved sptil resolution, which is especilly useful for smll msses (<1 cm) nd vlvulr lesions. However, it is invsive nd, s with TTE, provides only limited tissue chrcteriztion, often mking it impossile to confidently distinguish etween thromi nd enign nd mlignnt tumors (1). In recent yers, mgnetic resonnce imging (MRI) hs ecome the technique of choice for further differentition nd chrcteriztion of crdic mss ecuse it hs numerous dvntges over echocrdiogrphy, including n unrestricted field of view nd superior soft-tissue resolution (2). However, MRI is hevily relint on ptient coopertion to otin high qulity imges nd is not suitle for ll ptients. It is specificlly contrindicted in those ptients with clustrophoi or n implnted ferromgnetic device. Recent technologic dvnces in multi-detector computed tomogrphy (MDCT), including improvements in sptil nd temporl resolution in conjunction with ECG-gting, hve mde MDCT n extremely useful modlity for evluting crdic mss (3). ECG-gted MDCT should lso e considered Superior to MRI in some respects s it hs superior sptil resolution ( mm vs. 1 2 mm), cn definitively chrcterize ft nd clcifiction using ttenution mesurements nd cn simultneously evlute the coronry rteries. 67

2 c d Figure 1. d. A suspected mss locted ner the mitrl vlve. MDCT ws le to provide definitive ssessment in this cse, following n incomplete trnsthorcic echocrdiogrm (with limited coustic windows) nd inconclusive MRI study. A two-chmer SSFP MRI imge () showing focl thickening of the nterior mitrl vlve leflet (rrows). A fourchmer delyed-enhncement MRI imge () cquired 10 minutes fter injecting 0.1 mmol/kg gdolinium- DTPA nd using n inversion recovery pulse sequence to ttenute the signl from the norml myocrdium, showing sence of lte enhncement (rrows). A two-chmer imge from rteril phse ECG-gted MDCT (c). The improved sptil resolution of MDCT compred with MRI shows tht the nterior mitrl vlve leflet is split (rrows). This lesion is therefore diverticulum rther thn mss, s ws suspected on the sis of the MRI. Also note the thickening nd clcifiction of the su-vlvulr pprtus, which is most likely secondry to rheumtic fever. A delyed-phse MDCT imge (d) showing trpping of contrst medium within the diverticulum (rrows). LV, left ventricle; LA, left trium. Indeed, severl consensus sttements now include ECG-gted MDCT s recommended technique for evluting crdic msses (4). Occsionlly, crdic mss my e detected for the first time on non-ecg-gted thorcic MDCT studies performed for n unrelted indiction, nd rdiologists should e fmilir with its vrious chrcteristic fetures so tht they cn generte meningful differentil dignosis. This rticle descries the MDCT ppernces of the most common crdic pseudotumors nd neoplsms. Multidetector CT technique To provide isotropic sptil resolution, MDCT studies re idelly performed using t lest 64-detector row system (3). Non-ECG gted MDCT with intrvenous contrst infusion my e dequte for loclizing crdic mss. In the sence of ECG-gting, however, there re often significnt motion rtifcts, which cn preclude detecting smll lesions nd cuse lurring of the mrgins of lrger lesions, thus limiting the ssessment of locl extension. ECG-gting minimizes crdic motion-relted rtifcts, thus enling more precise evlution of lesion mrgins. Retrospective ECG-gting (continuous dt cquisition through the crdic cycle) is preferred over prospective ECG-gting (dt cquisition t single time point) ecuse it llows cine loops to e reconstructed, nd lesion moility cn e ssessed. Retrospective ECG-gting crries much higher rdition urden thn prospective ECG-gting (10 15 msv vs. 2 5 msv), however. Scnning from the crin to the crdic pex usully provides sufficient volume of coverge. We typiclly use 70 ml of iodinted contrst medium t 5 ml/s followed y 50%:50% contrst:sline flush, which helps mintin some opcifiction in the right hert chmers ut which is not so dense s to crete strek rtifcts. A follow-up study 2 3 min lter without dditionl contrst injection cn help with tissue chrcteriztion ecuse delyed enhncement within mss signifies contrst ccumultion in n expnded interstitium, such s within res of tumor necrosis. Delyed phse imges my lso e useful prolem-solving technique in cses where evlutions with echocrdiogrphy nd/or MRI hve een incomplete or inconclusive (Fig. 1). Prospective ECG-gting with low tue voltge (80 kv) nd norml tue current ( mas) hs een recommended to minimize rdition exposure while mximizing the contrst-to-noise rtio etween the tumor tissue nd norml myocrdium in delyed phse MDCT (5). 68 Jnury 2012 Dignostic nd Interventionl Rdiology Hoey et l.

3 The imges re reconstructed with 0.75-mm slice thickness nd red on viewing pltform with multi-plnr cpilities. The imges re initilly reviewed in the xil plne nd then reconstructed in the stndrd crdic imging plnes: verticl long xis (two-chmer), horizontl long xis (four-chmer), left ventriculr short xis, nd left ventriculr outflow trct (three-chmer). Figure 2. A left tril ppendge thromus in ptient with tril firilltion. This ECG-gted xil rteril phse MDCT imge shows low ttenution-filling defect within the left tril ppendge (rrows). PA, pulmonry rtery; LAA, left tril ppendge. Pseudotumors A vriety of non-neoplstic msses cn mimic crdic tumors nd should e recognized s such to void misdignosis. Intrcvitry thromi Thromi re the most common intrcrdic msses nd re the mjor differentil for ny intrcvitry lesion. Most thromi develop in regions of slow flow or round nidus, such s centrl venous ctheter tip. Common loctions for thromus re the left ventricle, in ssocition with neurysm formtion fter myocrdil infrctions, nd the left tril ppendge, in ptients with tril firilltion (Fig. 2). On MDCT, thromus ppers s well-circumscried, low-ttenution mss tht usully does not enhnce, even on delyed phse scns. Rrely, chronic thromi my show some peripherl enhncement due to the presence of firous pseudocpsule (Fig. 3). Chronic thromi my occsionlly contin clcifictions. The min differentil is tril myxom, for which there cn e considerle overlp of MDCT imging results. Indeed, recent study y Scheffel et l. (6) showed tht prolpse through the trioventriculr vlve orifice is the only relile feture fvoring myxom over left tril thromus on ECGgted MDCT; lesion size, origin, nd ttenution chrcteristics were poor discrimintors. Lipomtous hypertrophy Lipomtous hypertrophy of the tril septum descries n excess of norml rown ft in this region nd is considered n ntomicl vrint rther thn true neoplsm. Unlike n intertril lipom, which is the min differentil dignosis, it chrcteristiclly spres the foss ovlis, which gives it dumell-like ppernce (Fig. 4) (7). Volume 18 Issue 1 Norml ntomicl structures The crist terminlis is verticlly orientted firomusculr ridge tht runs long the posterior wll of the right trium; its size nd shpe my Figure 3.,. A left ventriculr thromus in ptient with ischemic crdiomyopthy. A non- ECG-gted xil rteril phse MDCT imge () showing sutle lminted thromus dherent to the interventriculr septum (rrows). The left ventricle is dilted, nd there re signs of decompenstion with ilterl pleurl effusions (sterisks). A delyed phse imge () showing non-enhncement of the thromus compred with the djcent myocrdium, which mkes it more conspicuous (rrows). RV, right ventricle. vry considerly mong individuls. The modertor nd extends oliquely cross the right ventricle, contins conduction fiers, nd should not e mistken for mss (3). Crdic neoplsms nd pseudotumors 69

4 Pericrdil cyst Pericrdil cysts re enign congenitl lesions tht rise from the pericrdium ut do not communicte with the pericrdil spce. They hve n incidence of 1: nd re most commonly locted t the right nterior crdiophrenic ngle, lthough they my occur nywhere in the medistinum (8). They re simple uniloculr lesions tht contin wter-sed fluid without internl sept. Although usully symptomtic, some ptients my complin of symptoms tht include chest pin nd persistent cough. MDCT shows homogenous, nonenhncing mss of wter ttenution (Fig. 5). Bronchogenic cyst Bronchogenic cysts re well-circumscried, thin-wlled, fluid-filled structures tht re thought to rise from the ronchil tree s result of norml udding of the ventrl foregut. Approximtely two-thirds re situted within the medistinum, most often in sucrinl or right prtrchel loction. MDCT shows shrply mrginted medistinl mss consisting of soft-tissue or wter ttenution. Pericrdil hemtom Pericrdil hemtoms usully result from prior crdic surgery, trum or myocrdil infrction. In n cute context, compression of the crdic chmers my impede distolic ventriculr filling nd led to hemodynmic compromise. Chronic hemtoms tend to ecome orgnized, often clcify, nd re frequent cuse of constrictive pericrditis. Clcifiction is mnifest s signl void on ll MRI pulse sequences, nd MDCT is the modlity of choice for definitive chrcteriztion (Fig. 6). Metstses Metstses to the hert nd pericrdium re times more common thn primry crdic tumors (9). They generlly pper lte in the course of the primry disese, nd isolted crdic involvement is rre in the sence of multi-orgn dissemintion. The spreding mechnisms include direct extension (Fig. 7) nd hemtogenous nd venous seeding (Fig. 8), with hemtogenous seeding eing the most common route for tumors of ronchil nd rest origin (the mjority of the primry lesions). The pericrdium is the most frequent site of involvement, which often tkes the form of mlignnt Figure 4. Lipomtous hypertrophy of the tril septum, which ws n incidentl finding on non-ecggted thorcic MDCT. An xil imge showing the clssicl uniform ft ttenution (-100 HU) nd dumell thickening of the tril septum (rrows), which spres the mid-septum (foss ovlis). LV, left ventricle. Figure 5.,. A pericrdil cyst tht ws n incidentl finding. An xil MDCT imge () showing well-circumscried nd uniformly low-ttenution structure in the right crdiophrenic ngle (rrows). A coronl T2-weighted MR imge () showing uniform high signl within the lesion (rrows), confirming its fluid content. RV, right ventricle; IVC, inferior ven cv. effusion. Aside from pericrdil effusions, metstses my lso mnifest on MDCT s multiple soft-tissue density msses (9). 70 Jnury 2012 Dignostic nd Interventionl Rdiology Hoey et l.

5 Figure 6. Constrictive pericrditis secondry to clcified pericrdil hemtom. This short-xis, rteril-phse ECGgted MDCT imge t the level of the mid portion of the left ventricle shows hevy pericrdil clcifiction (rrows). There is indenttion of the left ventricle, suggesting degree of hemodynmic compromise. RV, right ventricle; LV, left ventricle. Figure 7. The direct extension of ronchogenic crcinom into the left trium. This xil MDCT imge shows tumor extending long the right inferior pulmonry vein (rrows). LA, left trium. Figure 8.,. The hemtogenous spred of metstses from n dvnced testiculr tumor, s depicted y non-ecg-gted MDCT study. A coronl imge () showing lrge deposits filling nd expnding into the right ventricle (rrows). Also note severl left lung nodules. An xil imge () showing multiple deposits lodged within the proximl pulmonry rteries nd multiple prenchyml nodules (rrows). RA, right trium; LV, left ventricle. Primry crdic tumors Primry crdic tumors re rre, with n estimted lifetime incidence of 0.02% (10). The pproximte frequencies of the sutypes, tken from the surgicl nd pthology literture, re presented in Tle. The clinicl mnifesttions re non-specific nd depend on size, tumor type, nd loction. While some remin cliniclly silent, others present with symptoms, such s intrcrdic ostruction, tmponde, Volume 18 Issue 1 rrhythmis, nd systemic emoliztion (11). Benign primry tumors Most enign primry crdic tumors cn e completely resected with miniml moridity nd mortlity, nd mny ptients enjoy survivl similr to tht of the generl popultion (10). The typicl fetures include well-defined mss tht involves single crdic chmer nd hs nrrow trnsition zone. Myxom Myxoms ccount for 50% of ll enign primry crdic tumors nd my rise from pluripotent residul mesenchyml cells in the suendocrdium (11). The vst mjority rise within the tri, with 75% occurring on the left nd 15% 20% on the right side. A nrrow ttchment point t the foss ovlis of the tril septum is typicl, ut they cn originte from ny endocrdil surfce, including the vlves (1). Crdic neoplsms nd pseudotumors 71

6 Resection is required for definitive dignosis nd to prevent mjor complictions, especilly strokes secondry to the systemic emoliztion of left-sided tumor frgments (1). Most myxoms pper on MDCT s pedunculted low-ttenution intrcvitry msses (Fig. 9), lthough some myxoms re rod sed nd contin clcifictions. Lrge lesions my prolpse through the mitrl or tricuspid vlve orifices (Fig. 10) (6). Arteril phse enhncement is usully not pprent, ut delyed enhncement is recognized nd typiclly heterogeneous (6). Thromus is the mjor differentil dignosis, s hs een previously discussed. Firoelstom Firoelstoms re endocrdil ppilloms composed of collgen nd elstic-tissue fiers, with n endothelil covering nd connective tissue pedicle. They cn rise from ny endocrdil surfce, ut the mjority re found on the ortic nd mitrl vlves (12). Most re smll (<1 cm) nd remin cliniclly silent, ut there is the potentil for emoliztion into the systemic or pulmonry circultion from ccumulted thromi. Becuse of their smll size, TEE is the optiml mens of detection, nd MDCT ssessment is rrely indicted; however, they re occsionl findings on MDCT ppering s focl low ttenution vlve nodule (3). Firoelstoms re typiclly locted wy from the vlvulr free edge, nd the vlve function is usully preserved; this outcome is in contrst to endocrditis-induced vegettion, which lso ppers s low ttenution lesion ut which typiclly involves the vlvulr free edge nd cuses vlve destruction nd dysfunction (1). In our experience, we hve found multi-sequence MRI more useful thn MDCT in the preopertive work-up of suspected firoelstoms (Fig. 11). Lipom Lipoms re slow growing neoplsms composed of mture dipose tissue. They my rise from the epicrdil, myocrdil or endocrdil surfces, including the tril septum (7). Most ptients re symptomtic, ut these tumors re recognized cuse of rrhythmis, especilly tril firilltion. Lrge lipoms cn sometimes produce Tle. The pproximte frequency of enign nd mlignnt primry crdic tumors, dpted from references 10 nd 11 Benign Percentge Myxom 50% Firoelstom 15% Lipom 5% Firom 4% Other 1% Totl 75% Mlignnt Angiosrcom 10% Srcoms with myofirolstic differentition Undifferentited pleomorphic srcom 5% Osteosrcom 1% Leiomyosrcom <1% Firosrcom <1% Liposrcom <1% Myofirolstic tumor <1% Rhdomyosrcom 5% Primry lymphom 1% Pericrdil tumor Mesotheliom 2% Synovil srcom <1% Totl 25% Figure 9. A smll left tril myxom, which ws n incidentl finding. This xil MDCT imge shows well-circumscried, low-ttenution mss in reltion to the tril septum (rrows). A thromus cn hve n identicl CT ppernce; however, this lesion filed to resolve with nticogultion nd ws susequently surgiclly resected, which confirmed the dignosis of myxom. RA, right trium; LV, left ventricle. 72 Jnury 2012 Dignostic nd Interventionl Rdiology Hoey et l.

7 Figure 11. d. A firoelstom of the tricuspid vlve, which ws n incidentl finding in contrst-enhnced thorcic MDCT study performed for different indiction. An MRI ws performed for further chrcteriztion, nd the findings were typicl for ppillry firoelstom. An xil non-ecg-gted MDCT imge () showing tiny, well-circumscried lowttenution nodule within the right ventriculr cvity (rrows). A four-chmer SSFP MRI imge () nd coronl SSFP MRI imge (c) showing tht the nodule is ttched to the tricuspid su-vlvulr pprtus (rrows). A delyed gdoliniumenhnced imge (d) cquired 10 min following the injection of 0.1 mmol/kg gdolinium-dtpa nd using n inversion-recovery pulse sequence to ttenute the signl from the norml myocrdium. It shows complete sence of enhncement within the nodule (rrow), which supports of enign etiology. The morphologicl informtion provided y the MRI is most consistent with ppillry firoelstom. LV, left ventricle. c c d Figure 10. c. A lrge left tril myxom in ptient who presented with plpittions nd emolic phenomen. A distolic phse echocrdiogrm imge () showing lrge mss prolpsing through the mitrl vlve orifice (rrows). An xil ECG-gted MDCT imge () showing tht the lesion is ttched to the tril septum y nrrow pedicle (rrow) nd hs low ttenution nd villous mrgin. A two-chmer MDCT imge (c) in distole showing lesion prolpse through the mitrl vlve orifice (rrow), which is considered relile mens of distinguishing myxoms from thromi. RA, right trium; RV, right ventricle; LV, left ventricle. Volume 18 Issue 1 Crdic neoplsms nd pseudotumors 73

8 symptoms secondry to their compressive effects. Lipoms re difficult to dignose using echocrdiogrphy due to n extremely vrile echo-pttern (1). Both MRI nd MDCT re relile techniques for definitively chrcterizing ft. On MDCT, lipom ppers s well-circumscried lesion of homogeneous ft ttenution (-50 to -150 HU) (Fig. 12). Figure 12. An intertril lipom in ptient with suprventriculr tchycrdi. A four-chmer imge from n ECG-gted MDCT study showing lrge well-circumscried lesion (rrows) within the tril septum tht hs uniform ft ttenution (-110 HU). LV, left ventricle; RV, right ventricle. Firom Firoms re well-circumscried ggregtes of collgen nd firolsts tht rise in n intr-myocrdil loction, most often in the ventriculr septum or left-ventriculr free wll. Although histologiclly enign, they cn cuse ventriculr rrhythmis nd sudden deth from interference with conduction pthwys (2, 11). The mjority occur in infnts nd children, ut presenttion in dulthood lso occurs. On MDCT, firom ppers s discrete focl soft-tissue ttenution mss (Fig. 13) tht sometimes contins foci of clcifiction (3). Other enign tumors Rhdomyoms usully occur in ssocition with tuerous sclerosis. They re common in childhood ut tend to regress spontneously nd re rrely encountered in dults. On MDCT, they mnifest s single or multiple solid homogeneous msses rising in the left ventriculr myocrdium (1). Hemngioms re vsculr mlformtions composed of lood-filled, endothelil-lined, nd thin-wlled spces. Most ptients re symptomtic, nd they re often discovered incidentlly t crdic surgery, lthough exertionl dyspne is recognized presenttion. On MDCT, hemngioms pper s well-defined expnsile msses within the ventriculr myocrdium/pericrdium nd my contin clcifictions; enhncement is usully vid nd prolonged (3). Prgnglioms originte from crdic neuroendocrine cells, nd ptients typiclly present with symptoms of excess ctecholmines, e.g., hypertension nd flushing. Resection is usully curtive provided it is complete. On MDCT, prgnglioms pper s discrete, heterogeneous low-ttenution msses in the typicl crdic gngli distriution pthwys, i.e., t the root of the gret vessels nd long the wlls of the tri (2). Figure 13.,. A firom of the left ventricle in ptient with plpittions. A three-chmer MDCT imge () showing well-circumscried, soft-tissue ttenuted intr-myocrdil mss t the left ventriculr pex (rrows). A short-xis MDCT imge () tht gin shows the welldefined mrgins of this tumor (rrows). LV, left ventricle; RV, right ventricle. 74 Jnury 2012 Dignostic nd Interventionl Rdiology Hoey et l.

9 Figure 14.,. An ngiosrcom rising from the right tril free wll in ptient with symptoms of right hert filure. An xil T1-weighted MR imge () showing lrge mss with mixed signl intensity centered on the right trium (rrows). The centrl high signl res my reflect hemorrhgic foci within this highly vsculr lesion. An xil T2-weighted MR imges () showing tht the lesion hs high wter content (rrows), which is very suggestive of mlignnt etiology. LV, left ventricle; RV, right ventricle. Mlignnt primry tumors Imging findings suggestive of mlignnt crdic tumor include right tril loction, involvement of more thn one crdic chmer, size >5 cm, hemorrhgic pericrdil effusion, rod se of ttchment, extension into the medistinum or gret vessels, nd delyed enhncement (13). Srcoms Srcoms ccount for the mjority of primry mlignnt crdic tumors nd re the second most common primry tumor fter myxoms. Histologiclly, they re clssified into three min sugroups: ngiosrcoms, srcoms with myofirolstic differentition, nd rhdomyosrcoms (11). Angiosrcoms Angiosrcoms re highly ggressive neoplsms composed of irregulr vsculr chnnels lined y nplstic epithelil cells. The pek incidence is in the fourth decde, nd there is strong mle predominnce. The mjority originte in the right trium; they typiclly fill this chmer, with infiltrtion long the pericrdium nd into the tricuspid vlve nd right coronry rtery (1, 2). The clinicl presenttion usully occurs t n dvnced stge, with symptoms of right hert filure nd/or crdic tmponde (11). Distnt metstses re present in up to 90% of the cses t the time of dignosis; these metstses most frequently Volume 18 Issue 1 occur in the lungs, liver, nd rin. The prognosis is dire, with few ptients surviving eyond 12 months (14). MRI is the technique of choice for ssessing the precise reltionship of the tumor to djcent structures if resection or deulking surgery is eing contemplted (Fig. 14). On imging studies, ngiosrcoms typiclly pper s lrge msses with heterogeneous composition, often in ssocition with sheet-like pericrdil thickening nd hemorrhgic pericrdil effusion. Srcoms with myofirolstic differentition This group of tumors is diverse nd my contin heterologous elements, such s one. They occur predomintely in dulthood nd re su-clssified s undifferentited srcoms, leiomyosrcoms, firosrcoms, liposrcoms, nd osteosrcoms. They most often originte long the posterior wll of the left trium nd tend to exhiit slow infiltrtive growth ptterns (3). Their infiltrtive nture is redily pprecited on MDCT, which helps differentite them from thromi nd myxom (Fig. 15). Clcifictions should lert physicins to the possiility of n osteosrcom. Liposrcoms rrely contin sufficient mounts of mcroscopic ft to permit confident dignosis sed on their morphologic imging chrcteristics (2). Rhdomyosrcoms Rhdomyosrcoms re mlignnt tumors of strited muscle. Although they ccount for only round 5% of dult primry crdic tumors, they re the most common peditric crdic mlignncy. Rhdomyosrcoms my rise nywhere in the myocrdium, with tendency towrds multiple sites of origin, vlvulr involvement nd extension into the pericrdil spce. On MDCT, they usully pper s lrge infiltrtive mss tht my contin centrl res of necrosis (Fig. 16). When the pericrdium is involved, it usully hs nodulr ppernce; this finding is in contrst to ngiosrcoms, which usully produce sheet-like thickening (1). Primry crdic lymphoms Primry crdic lymphom descries disese tht is confined to the hert or pericrdium, which distinguishes it from the more common cse of crdic involvement y non-hodgkin s lymphom (3). Most of these lymphoms occur in immunocompromised ptients, re of B-cell origin, nd follow n ggressive clinicl course. Unlike other primry crdic mlignncies, they often hve fvorle response to chemotherpy. The right trium is reported to e the most common site, ut unlike srcoms, they re less likely to hve necrosis nd rrely involve the vlves (1). The imging findings re non-specific, Crdic neoplsms nd pseudotumors 75

10 c Figure 15. c. A srcom with myofirolstic differentition in ptient with symptoms of left hert filure tht ws evluted with ECG-gted MDCT. A two-chmer rteril phse MDCT imge () showing loulted mss rising from the roof of left trium (rrows) nd utting the nterior mitrl vlve leflet (rrowhed). A coronl rteril phse imge () through the ody of left trium showing tht the mss is ttched to its lterl wll nd is infiltrting into the left inferior pulmonry vein (rrows) nd reching the pericrdium. An xil delyedphse imge (c) showing ptchy res of lte enhncement (rrows), which implies differentil wshout kinetics within this mlignnt lesion. LV, left ventricle; LA, left trium. Figure 16.,. A rhdomyosrcom in ptient with chest pin nd weight loss. An xil MDCT imge () t the level of the ortic root showing tumor infiltrtion surrounding the left nterior descending coronry rtery (rrows). Also note the presence of pulmonry metstsis (rrowhed). Axil MDCT imge () t the level of the left trium shows lrge infiltrtive mss centered on the left ventriculr free wll (rrows). Ao, ortic root. 76 Jnury 2012 Dignostic nd Interventionl Rdiology Hoey et l.

11 ut they usully pper s isottenuting reltive to myocrdium on MDCT. Severl morphologic sutypes hve een descried, including solitry nodulr mss nd diffuse infiltrtive process, often in ssocition with extensive pericrdil effusion. Primry pericrdil mlignncy Mesotheliom cn rise from the pericrdil mesothelil cell lyer. An ssocition with sestos exposure is ssumed ut yet to e estlished, owing to the rrity of these tumors. They cuse progressive pericrdil encsement with rethlessness nd chest pin; the prognosis is dire, with few surviving eyond 12 months from the time of dignosis (15). MDCT is superior to MRI for these tumors ecuse the lung prenchym nd pleur cn e simultneously evluted for signs of sestos-relted disese, i.e., clcified pleurl plques, diffuse pleurl thickening, nd interstitil firosis. Pericrdil mesothelioms pper s multiple enhncing nd colescing pericrdil msses tht envelop the pericrdil spce ut rrely infiltrte deep into the underlying myocrdium. As with pleurl mesothelioms, long dely time (70 90 s) is recommended for the initil set of imges ecuse this tumor is typiclly poorly vsculrized nd my not e optimlly visulized in n rteril phse study (Fig. 17). Pericrdil synovil srcoms re extremely ggressive tumors tht re composed of spindle nd epithelioid cells, with imging fetures tht show considerle overlp with ngiosrcoms. A heterogeneously enhnced multi-loulted mss with extensive pericrdil infiltrtion nd deep invsion on MDCT hs een descried. As conclusion, MDCT cn provide useful complimentry informtion to echocrdiogrphy nd MRI for ssessing suspected crdic mss; in some instnces, it is the modlity of choice for definitive chrcteriztion. In prticulr, MDCT offers high sptil resolution, fst cquisition times nd the ility to definitively chrcterize ft nd clcifiction. Rdiologists should e fmilir with the key distinguishing fetures of oth neoplstic nd nonneoplstic msses, s highlighted in this review. Conflict of interest disclosure The uthors declred no conflicts of interest. References 1. Sprrow PJ, Kurin JB, Jones TR, Sivnnthn MU. MR imging of crdic tumors. Rdiogrphics 2005; 25: Syed IS, Feng D, Hrris SR, et l. MR imging of crdic msses. Mgn Reson Imging Clin N Am 2008; 16: Hoey E, Mnkd K, Puppl S, Gopln D, Sivnnthn MU. MRI nd CT ppernces of crdic tumours in dults. Clin Rdiol 2009; 12: Cronro, S, Villines TC, Husleiter J, Devine PJ, Gerer TC, Tylor AJ. Interntionl, multidisciplinry updte of the 2006 Appropriteness Criteri for Crdic Computed Tomogrphy. J Crdiovsc Comput Tomogr 2009; 3: Brodoefel H, Klumpp B, Reimnn A, et l. Lte myocrdil enhncement ssessed y 64-MSCT in reperfused porcine myocrdil infrction: dignostic ccurcy of low-dose CT protocols in comprison with mgnetic resonnce imging. Eur Rdiol 2007; 17: Figure 17. Pericrdil mesotheliom in ptient with progressive dyspne. This lte phse (90 s) non-ecg-gted xil MDCT imge shows enhncing circumferentil nodulr pericrdil msses (rrows). RV, right ventricle; LV, left ventricle. 6. Scheffel H, Bumueller S, Stolzmnn P, et l. Atril myxoms nd thromi: comprison of imging fetures on CT. AJR Am J Roentgenol 2009; 192: Slnitri JC, Pereles FS. Crdic lipom nd lipomtous hypertrophy of the intertril septum: crdic mgnetic resonnce imging findings. J Comput Assist Tomogr 2004; 28: Grizzrd JD, Ang GB. Mgnetic resonnce imging of pericrdil disese nd crdic msses. Mgn Reson Imging Clin N Am 2007; 15: Chiles C, Woodrd PK, Gutierrez FR, Link KM. Metsttic involvement of the hert nd pericrdium: CT nd MR imging. Rdiogrphics 2001; 21: Elrdissi AW, Derni JA, Dly RC, et l. Survivl fter resection of primry crdic tumors: 48-yer experience. Circultion 2008; 118: Burke A, Jeudy Jr J, Virmni R. Crdic tumours: n updte. Hert 2008; 94: Gowd RM, Khn IA, Nir CK, Meht NJ, Vsvd BC, Scchi TJ. Crdic ppillry firoelstom: comprehensive nlysis of 725 cses. Am Hert J 2003; 146: Hoffmnn U, Gloits S, Schim W, et l. Usefulness of mgnetic resonnce imging of crdic nd prcrdic msses. Am J Crdiol 2003; 92: Pigott C, Welker M, Khosl P, Higgins RS. Improved outcome with multimodlity therpy in primry crdic ngiosrcom. Nt Clin Prct Oncol 2008; 5: Kinum S, Msi T, Ymuchi T, Tked K, Ito H, Sw Y. Primry mlignnt pericrdil mesotheliom presenting s pericrdil constriction. Ann Thorc Crdiovsc Surg 2008; 14: Volume 18 Issue 1 Crdic neoplsms nd pseudotumors 77