T o o muc h me dic ine a nd ve no us thro mb o e mb o lism: Ho w - PowerPoint PPT Presentation

T o o muc h me dic ine a nd ve no us thro mb o e mb o lism: Ho w c a n we ma ke thing s “We ll” a g a in? E mily G Mc Do na ld MD MSc ; Assista nt pro fe sso r o f me dic ine ; Mc Gill Unive rsity He a lth Ce ntre Ca na dia n So c ie ty o f Inte rna l Me dic ine ; No ve mb e r, 2017; T o ro nto , Ca na da

Ob je c tive s:  De sc rib e the ro o t o f the pro b le m: o ve rd ia g no sis a nd o ve rtre a tme nt o f ve no us thro mb o e mb o lism  Ca se o f CT pulmo na ry a ng io g ra m (a nd ve no us Do pple r) o ve ruse  Disc uss whe n a ntic o a g ula tio n ma y no t b e re q uire d  Disc uss pra c titio ne r va ria b ility in the inve stig a tio n o f VT E  Re d uc e o ve r-inve stig a tio n, o ve rd ia g no sis, a nd o ve rtre a tme nt o f VT E within yo ur pra c tic e

Co nflic ts o f inte re st:  Inte lle c tua l inte re st in re d uc ing o ve ruse a nd o ve rtre a tme nt a nd ”wind ing b a c k the ha rms o f to o muc h me d ic ine ”  Gra nts re c e ive d fro m the Ca na d ia n Institute s o f He a lth Re se a rc h a nd the Ca na d ia n F ra ilty Ne two rk to stud y d e pre sc rib ing a nd c o -c re a to r o f Me d Sa fe r, a to o l to sto p me d ic a tio ns in o ld e r a d ults (pa te nt pe nd ing )  I’ m no t a n e xpe rt in thro mb o sis  I’ ve no t e ve r ta ke n o r re c e ive d pha rma -re la te d mo ne y/ me rc ha nd ise

T hro mb o sis: a b it o f histo ry  F irst writte n re fe re nc e : in a nc ie nt Ind ia n me d ic a l te xts, physic ia n a nd surg e o n Susruta (c irc a 600 BCE ) d e sc rib e s a pa tie nt with a pa inful swo lle n le g tha t is d iffic ult to tre a t.  Mid -1800s, Je a n Cruve ilhie r, pro mine nt F re nc h pa tho lo g ist, pro po se d a c e ntra l ro le fo r ve no us infla mma tio n a nd thro mb o sis in a ll d ise a se c o nd itio ns “phle b itis d o mina te s a ll o f pa tho lo g y”

And who is this?

Rudo lph Virc ho w

Virc ho w’ s tria d

Onc e the pa tho lo g y wa s ide ntifie d, the c ha lle ng e b e c a me dia g no sis. Histo ry o f the dia g no sis o f pulmo na ry e mb o lism

Dia g no sis o f PE  Prio r to the 1960s the c linic al d ia g no sis wa s ne ithe r se nsitive no r spe c ific  E K G (S1Q3T 3), CXR (we ste rma rk’ s sig n a nd Ha mpto n’ s hump), physic a l e xa m

Re f: Da le n JE , Alpe rt JS. Na tura l histo ry o f pulmo na ry e mb o lism. Pro g Ca rdio va sc Dis 1975 ;17:259–70

Dia g no sis o f pulmo na ry e mb o lism  Pulmo na ry a ng io g ra ms (first c a se se rie s 1964)  L ung sc a n (1960s)

Pulmo na ry Ang io g ra phy in PE  Wa s the “g o ld sta nd a rd ”; a ne g a tive pulmo na ry a ng io g ra m e xc lud e s c linic ally r e le vant PE .  Inva sive me tho d a nd no lo ng e r pe rfo rme d re pla c e d b y CT a ng io g ra m sinc e 2000 in E uro pe a nd 2006 in No rth Ame ric a

Ve ntila tio n-Pe rfusio n Sc a ns  Use ful if no rma l (ne g a tive pre d ic tive va lue o f 97%)  Also use ful if High pr obability (po sitive pre d ic tive va lue o f 85 to 90%)  Unfo rtuna te ly, o nly d ia g no stic in 30 to 50% o f pa tie nts

 PIOPE D stud y (1990 JAMA)--> the impo rta nc e o f pre -te st pro b a b ility  In this la nd ma rk tria l we le a rn: the c o mb ina tio n o f hig h c linic a l pro b a b ility a nd a hig h pro b a b ility sc a n e q ua ting to the pre se nc e o f PE a nd a lo w c linic al pro b a b ility with a lo w pro b a b ility sc a n e xc lud ing PE

Ve ntila tio n-pe rfusio n sc a ns  De spite PIOPE D 2, c o nc e rns a b o ut spe c ific ity o f V/ Q  re po rting po sitive o r ne g a tive finding s in sha de s of g r a y  Only dia g no stic in 30 to 50% o f pa tie nts  Clinic ia ns c o ntinue d to se a rc h fo r a ye s/ no te st fo r a c ute PE  CT CT rapidl idly evolv lved t to fill t ll this rol ole  We re it no t fo r de finite a lle r isks o f g ic a nd ne phr otoxic r c o ntra st me dia a nd the a dde d r a dia tion b urde n o f MDCT A, the ve ntila tio n/ pe rfusio n sc a n wo uld virtua lly disa ppe a r fro m the dia g no stic a lg o rithm fo r pulmo na ry e mb o lism.

CT sc a ns- impro ve me nts me a n g re a te r de te c tio n ra te  In 1992, Re my-Ja rd in re po rte d the use o f spira l CT sc a nning fo r c e ntra l PE . T he stud y c o nc lud e d tha t spira l CT ha d a se nsitivity o f 100% a nd spe c ific ity o f 96% fo r a d ia g no sis o f c e ntra l PE .  In 1995, Go o d ma n a nd c o lle a g ue s--> CT se nsitivity 86%, spe c ific ity 92%, a nd like liho o d ra tio 10.7.  Whe n subse gme ntal ve sse ls we r e inc lude d, howe ve r , se nsitivity was 63% , spe c ific ity 89% , and like lihood r atio 5.7.

Ca se o f o ve r-inve stig a tio n a nd o ve rdia g no sis  With this in mind le t’ s c o nside r a c a se

Ca se e xa mple o f o ve r-inve stig a tio n  40 fe ma le with no pa st me d ic a l histo ry o n the o ra l c o ntra c e ptive pill pre se nts to a c o mmunity c linic a fte r a flig ht ho me fro m F ra nc e with ne w le ft c a lf pa in

I mpre ssio n a nd pla n:  “Hig h risk fo r DVT a nd PE ” ( like ly b e c a use o f the histo ry o f a irpla ne tra ve l)  No me ntio n o f the We ll’ s sc o re  CT pulmo na ry a ng io g ra m is pe rfo rme d  No CXR  No D-d ime r  No d o pple r

CT -Pulmo na ry e mb o lus  De spite two inje c tions, the bolus of c ontr ast is le ss than ade quate fo r a sse ssing se g me nta l a nd sub se g me nta l b ra nc he s. No filling d e fe c ts id e ntifie d within the ma in pulmo na ry a rte rie s.  T he re is a q ue stio na b le filling d e fe c t in a la te ra l lo we r lo b e se g me nta l b ra nc h se e ima g e 151 se rie s 5.  If pulmo nary e mb o lism str o ngly suspe c te d wo uld re c o mme nd a re pe at e xaminatio n in this patie nt o r a ve ntilatio n pe rfusio n sc an.

CT PA fo r sub se g me nta l PE F a lse Po sitive Appa re nt filling de fe c ts L ung windo w re ve a ls mo tio n a rtifa c t

CT PA fo r sub se g me nta l PE F a lse Po sitive / Re pro d uc ib ility T he r e is r e lative ly poor inte r obse r ve r agr e e me nt for subse gme ntal and/ or small pulmonar y ar te r y de fe c ts, e spe c ially in CT pulmonar y angiogr ams de gr ade d by te c hnic al ar tifac ts.

T a ke ho me po int:  CT PA a s first-line ima g ing fo r suspe c te d pulmo na ry e mb o lism c a n inc re a se the d e te c tio n o f sma ll, sub se g me nta l pulmo na ry e mb o lism, whic h mig ht ha ve a q ue stio na b le c linic al re le va nc e (fa lse po sitive / o ve rd ia g no sis)

A c a se inspire s a study

Study pe rfo rme d a t the MUHC  We re tro spe c tive ly re vie we d a ll CT PA a t a n a c a d e mic te a c hing ho spita l in Mo ntré a l, Ca na d a , fro m Se pte mb e r 2014 to Ja nua ry 2016.  A to ta l o f 1394 e xaminations or de r e d by 182 physic ians we r e e positive . A multiva ria b le inc lude d, of whic h 199 (14.3% ) we r lo g istic re g re ssio n a na lysis wa s pe rfo rme d to e xplo re whe the r physic ia n spe c ia lty, ye a rs in pra c tic e , physic ia n se x, o r to ta l numb e rs o f stud ie s o rd e re d pe r physic ia n we re a sso c ia te d with CT PA d ia g no stic yie ld . Cho ng J, L e e T , Siva kuma ra n L , Ga llix B, Mc Dona ld E G ; a c c e pte d fo r pub lic a tio n No v 1 st , 2017; JAMA inte rna l me dic ine (IN PRE SS)

Study pe rfo rme d a t the MUHC  Via GE E lo g istic re g re ssio n, the odds of a positive CT PA de c r e ase d as the total numbe r of sc ans or de r e d pe r e ase d . physic ian inc r  F or e ac h additional te n studie s or de r e d, the odds of a positive r e sult de c r e ase d [OR 0.76; (95% CI 0.73- 0.79)]. Cho ng J, L e e T , Siva kuma ra n L , Ga llix B, Mc Dona ld E G ; a c c e pte d fo r pub lic a tio n No v 1 st , 2017; JAMA inte rna l me dic ine (IN PRE SS)

T ABL E 1: Positive CT PA E xa mina tions for All Physic ia ns T a b le o f the Numb e r o f Physic ia ns, Studie s, a nd Numb e r/ Pe rc e nta g e o f Po sitive CT PA with Ma jo r Spe c ia lty Gro uping s. Physic ia ns we re stra tifie d b y the to ta l study vo lume the y o rde re d during the o b se rva tio n pe rio d. Stud y Vo lume Numb e r o f Physic ia ns Numb e r o f CT PA Numb e r o f Po sitive CT PA Physic ia n Stud ie s (%) Sp e c ia lty Gro up : ER, Othe r (%) 1-10 145 411 85 (20.7) ER: 13 (9.0) Othe r: 132 (91.0) 11-20 14 228 37 (16.2) ER: 8 (57.1) Othe r: 6 (42.9) 21-30 9 198 30 (15.2) ER: 8 (88.9) Othe r: 1 (11.1) 31-40 6 179 20 (11.2) ER: 5 (83.3) Othe r: 1 (16.7) 41-50 5 219 19 (8.7) ER: 5 (100.0) > 50 3 159 8 (5.0) ER: 3 (100.0) T OT AL 182 1,394 199 (14.2) ER: 42 (23.1) Othe r: 140 (76.9) Cho ng J, L e e T , Siva kuma ra n L , Ga llix B, Mc Donald E G ; a c c e pte d fo r pub lic a tio n: No v 1 st , 2017; JAMA inte rna l me dic ine (IN PRE SS)