Resul t s : Mitral regurgi tat ion was the mos t c o m m o n valvular ab- normali ty seen in 77% (105/136) fol lowed by mitral s tenosis in 14% (19/136) and combined stenosis and regurgitation in 9% (12/ 136). The majority o f mitral regurgitation was non-rheumatic in ori- gin (88/105). Ches t radiographic f indings in non- rheumat ic nfitral regurgitat ion included cardiac en largement in 67% (59/88), pul- monary venous hyper tens ion in 58% (51/88), and left atrial en- largement in 41% (36/88). The mos t c o m m o n f inding in rheumat ic mitral regurgi tat ion was pu lmonary venous hyper tens ion in 70% (12/17) fol lowed by card iomegaly and left atrial en la rgement seen in 65% (11/17) each. In compar ison, pu lmonary venous hyperten- sion and left atrial enlargement were the c o m m o n f indings seen in 95% and 74% respectively, in patients with mitral stenosis. In 53% of these patients, there was no cardiac enlargement . Ches t radio- graphs underes t imated the left atrial en la rgement detected at echo- cardiography (51% vs. 89%).

Conclus ions : (1) Non-rheumat ic mitral regurgitation is the mos t c o m m o n form of M V D encountered today. (2) Whi le diagnosis o f mitral s tenosis f rom chest radiograph is often possible, d iagnos ing non-rheumat ic mitral regurgi tat ion is difficult. (3) In about 25% of patients with mitral stenosis, the only radiographic abnormal i ty is pu lmonary venous hypertension.

0 3 - 1 4 CT Depict ion of in Situ Vascular Stump Thrombosis Following Pulmonary Resect ion for Cancer Ange la J. Gessner , MD, Thomas Jefferson University Hospital, Philadelphia, PA, Richard J. Wechsler , MD, A n a M. Salazar, MD, Paul W. Spiru, MD, Robert M. Steiner, M D

P u r p o s e : To assess the incidence and s ignif icance o f vascular s tump thrombosis found on C T scans performed fol lowing lung resect ions for carcinoma.

Me thods /Ma te r i a l s : A computer search of C T chest scan reports be tween 1994 and 1997 identif ied 265 scans on 90 patients fol- lowing pu lmonary lobec tomy or pneumonec tomy . These scans were reviewed by two radiologists in concert to identify vascular s tump int ra luminal defects and/or concomitant pu lmonary embol i in other lung segments . The medical records of the involved pa- tients were reviewed for predisposing thrombogenic factors, suspi- c ion o f pu lmonary embol i and adjuvant studies.

Resu l t s : Six patients, all with r ight sided lobec tomy or pneu- monec tomy, were identified as hav ing pu lmonary arterial intralu- minal clot. T h r o m b u s in four patients was only identified at the s tump site without clot e lsewhere in the lung. Pu lmonary emboli were found in two patients without s tump thrombosis, 1 with posi- tive lower extremity Doppler examinat ion, the other having a negative inferior vena cavogram before filter placement.

Conc lus ions : Incidental s tump thrombosis was found in 4% of patients fol lowing pu lmonary resect ion and does not appear to be a r isk factor for pu lmonary embol i sm.

0 3 - 1 5 Plain Film Diagnosis of Congenital Heart Disease Laura M. Fayad, MS, MD, Columbia-Presbyterian Medical Cen- ter, New York, NY, Lawrence M. Boxt, M D

P u r p o s e : To develop a cl inical ly re levant approach to the diag- nosis o f congeni ta l heart d i sease based upon plain f i lm changes caused by ma l fo rma t ions and their phys io logic sequelae.

Materials, M e t h o d s & R esu l t s : In pat ients with heart disease, congeni ta l ma l fo rma t ions cause al terat ions o f cardiac func t ion wh ich resul t in radiographic changes in the appearance o f the hear t and pu lmona ry vasculature . Phys io logic changes resul t in cardiac chambe r dilatat ion and myocard ia l hyper t rophy, both o f which resul t in changes in the appearance o f left and r ight heart border - fo rming structures. Sequent ia l analys is o f these changes in the pos teroanter ior (PA) radiograph, and correlat ion with changes in the sharpness , caliber, and distr ibution of the paren-

chyma l pu lmona ry blood vesse ls provide the basis for e lucidat ing these pa thophys io log ic m e c h a n i s m s , a l lowing d iagnosis o f the congeni ta l mal format ions . No clinical in format ion is a s s u m e d in this formulat ion.

C o n e l u s l o n : A cl inically re levant me thod for d iagnos ing and c lass i fy ing congeni ta l heart d isease is constructed, based upon the PA ches t f i lm presenta t ion o f these mal format ions .

0 3 - 1 6 FDG-PET and CT Assessment of Peripheral and Cen- tral Lung Lesions A n g e l a Lignell i , MD, Columbia Presbyterian Medical Center, New York, NY, John H. Aus t in , MD, Gregory D.N. Pearson, MD, PhD, Chitra Manoj , Ronald L. Van Heer tum, M D

P u r p o s e : To evaluate ma l ignancy of per ipheral vs. central lung les ions by us ing f luorodeoxyg lucose (FDG) PET and C T criteria.

Methods and M a t e r i a l s : Twen ty -one adul t patients , ages 38 to 84 yrs., wi th lung nodules or m a s s e s were studied. Les ions ranged in size f rom l c m to 6 c m at CT. Peripheral lesions were def ined as les ions located a d is tance o f 2.0 cm or less f rom vis- ceral p leura while all other les ions were classif ied as central. Based on ches t CT, les ions were def ined as mal ignan t or ben ign us ing ana tomic criteria wh ich included spicnlat ions, presence and pat tern o f calcif icat ions, shape and size. Standardized uptake value (SUV) of >2.5 was accepted as the ma in F D G - P E T crite- r ion for ma l ignancy . A total o f 11 les ions were classif ied as cen- tral and 10 as peripheral , Final ma l ignancy status was de te rmined by b iopsy or a 2 year m i n i m u m clinical fol low-up. Mal ignan t le- s ions compr i sed 6/11 central les ions and 2/10 peripheral lesions.

Resul t s : PET and CT determination o f likelihood of mal ignancy was concordant in 10/11 o f the central lesions, and 4/10 peripheral lesions. The following table is included to summar ize the results:

CT correct PET correct

Central mal ignant 6/6 6/6

Central ben ign 4/5 5/5

Peripheral mal ignant 2/2 0/2

Peripheral benign 4/8 7/8

Of the 2 mal ignant peripheral lesions both were biopsied with the first lesion d iagnosed as metastat ic renal cancer and the second one as combined large and small cell lung cancer with neuroendo- crine features. For both central and peripheral lesions combined sen- sitivity of CT was found to be 100% and specificity 62%, while for PET overall sensit ivi ty was 75% and specificity 92%.

Cone lus ions : Both CT and PET appear to be concordant in cor- rectly characterizing central lung lesions as mal ignant or benign. For peripheral lesions neither technique is consis tent ly accurate in determining mal ignancy as CT appears to have a lower specificity with respect to PET, but PET in turn has a lower sensitivity. W e plan to expand this series in an at tempt to further delineate whether malignancy of lung lesions may be assessed based on criteria o f lo- cation, me tabo l i sm and anatomic appearance.

0 3 - 1 7 Work.up of Pulmonary Embolism in a Teaching Hospi- tal: Prel iminary Analysis of Data from 683 Pat ients Max P. Rosen, MD, Beth Israel Deaconess Medical Center, Bos- ton, MA, Roger Davis , ScD, Daniel Z. Sands, MD, MPH, W h i t n e y Drake, Karen M. Kuntz , ScD

Purpose: The purpose o f our s tudy is to (1) D o c u m e n t M D s ' ability to accurate ly assess the clinical l ikel ihood of pu lmona ry e m b o l i s m (PE), (2) Ident i fy pat ient and phys ic ian characteris t ics associa ted with an incomple te work-up for PE and (3) As se s s the impac t o f an incomple te work-up for PE on pat ient survival .

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