A IV IV.1 76

MC LC

I. BNH NG MCH VNH .................................................................................... 1

1.1 Tng quan........................................................................................................... 1

1.2 Cha tr .............................................................................................................. 2

1.3 Bnh mch vnh bnh nhn tiu ng ........................................................... 2

1.4 Bnh mch vnh ph n .................................................................................. 2

1.5 Bnh mch vnh ngi cao tui ....................................................................... 4

II. TNG QUAN V BNG NONG MCH ............................................................... 5

2.1 S lc lch s v bng nong mch (balloon catheter) ........................................ 5

2.2 Phn loi ............................................................................................................. 5

2.2.1 Bng p lc cao (bng cng) ........................................................................ 5

2.2.2 Bng p sut thp (bng mm) ..................................................................... 6

2.3 Vt liu bng ...................................................................................................... 7

2.4 Cng dng .......................................................................................................... 8

2.4.1 Gin n ......................................................................................................... 8

2.4.2 Phn phi stent (Stent delivery) .................................................................... 8

2.4.3 Phn phi thuc (Drug delivery) ................................................................... 9

III. MI QUAN H GIA BNH TIU NG V NG MCH VNH ....... 11

3.1 Tng quan......................................................................................................... 11

3.2 Phng php iu tr bnh MV bnh nhn tiu ng ................................ 12

3.2.1 Th thut bc cu ........................................................................................ 13

3.2.2 Nong mch vnh v t stent ...................................................................... 13

IV. NG MCH VNH PHN NHNH ................................................................ 16

4.1 Gii thiu ......................................................................................................... 16

4.2 Phn loi ........................................................................................................... 16

4.3 Stent n v stent i........................................................................................ 17

4.3.1 Phng php t mt stent .......................................................................... 18

4.3.2 Phng php t hai stent ........................................................................... 18

4.4 Kissing balloon ................................................................................................. 20

V. NGHIN CU QUY TRNH NH GI P SUT N NH MC CA

BNG CA STENT THNG .................................................................................. 22

5.1 Dng c, thit b ............................................................................................... 22

5.2 Quy trnh thc hin ........................................................................................... 23

5.3 Kt qu v tho lun ......................................................................................... 24

VI. KT LUN ............................................................................................................ 27

TI LIU THAM KHO ........................................................................................... 28

DANH MC HNH

Hnh 1: Cc cn bnh chnh gy t l t vong cao nht trn th gii vo nm 2011 (trong

bnh hp ng mch vnh dn u) ............................................................................ 1

Hnh 2: T l mc bnh ng mch vnh nam gii v n gii t nm 1997 n 2009 ... 3

Hnh 3: Bng nong vnh ng mch ................................................................................ 5

Hnh 4: Bng nong p lc cao (non-compliance) ............................................................. 6

Hnh 5: Bng p lc thp (compliance) ........................................................................... 6

Hnh 6: Cng thc phn t ca polyvinyl chloride (PVC) ................................................ 7

Hnh 7: Qu trnh to vt liu polymer ............................................................................ 7

Hnh 8: Bng vi thit k m hnh xng ch................................................................... 9

Hnh 9: Bng c mng a ng thuc - thuc thot ra ngoi mng bng ....................... 10

Hnh 10: Qu trnh gy tn thng mch mu bnh tiu ng .................................. 11

Hnh 11: So snh nguy c nhi mu c tim v cht ca cc loi stent( tin cy 95%). . 14

Hnh 12: So snh kh nng hnh thnh huyt khi ca cc loi stent ( tin cy 95%). .. 15

Hnh 13: Kiu phn loi vng ng mch phn nhnh Lefevre ...................................... 16

Hnh 14: Kiu phn loi vng ng mch phn nhnh Medina ...................................... 17

Hnh 15: Phng php t mt stent .............................................................................. 18

Hnh 16: Cc phng php t hai stent ........................................................................ 19

Hnh 17: Phng php t stent th hai thng qua thanh chng stent th nht ............. 20

Hnh 18: Phng php m rng vng tt nghn v tr mch phn nhnh bng kissing

balloon. .......................................................................................................................... 20

Hnh 19: Kissing balloon trong trng hp dng hai stent ............................................ 21

Hnh 20: Bn nc (c th kim sot c nhit ) ...................................................... 23

Hnh 21: Bng v khi vt qua p sut n nh mc ...................................................... 24

Hnh 22: M hnh kim tra p sut n nh mc ca bng ............................................. 24

Hnh 23: Chiu di bng thay i khi thay i p sut (a) v chiu di thay i ph thuc

vo mi loi stent (b) ..................................................................................................... 26

DANH MC BNG

Bng 1: Bng so snh cc vt liu lm bng. ................................................................... 8

Bng 2: Bng so snh t l to huyt khi sau khi t mt stent v hai stent ng mch

chnh v nhnh (sau 6 thng) ......................................................................................... 18

Bng 3: Bng kt qu o p sut n nh mc 10 bng stent trn .................................. 24

Bng 4: Kt qu o p sut n nh mc ca bng lm t vt liu khng tng thch .... 25

I. BNH NG MCH VNH

1.1 Tng quan

Bnh ng mch vnh (MV) gy nn bi nhng mng bm c hnh thnh t

m, cholesterol v cc cht khc trn thnh ng mch vnh. Lu dn, cc mng bm ny

ln ln v lm hp dng chy ca mu, ng thi lm gim lng mu cha cht oxy dn

v tim. Hin nay trn ton th gii c khong 40 triu ngi mc bnh ng mch vnh

(MV). Mi nm c thm khong 5,8 triu ngi mc BMV. BMV l nguyn nhn gy

t vong hng u trong cc bnh tim mch. Ring nm 2001 c 7,2 triu ngi cht v

BMV. Ti Vit nam BMV ang tng ln mt cch r rt. Theo cc s liu thng k th t

trc nm 1963 BMV l rt him gp, sau nm 1963 BMV bt u gia tng. Ring ti

TP H Ch Minh trong nm 2000 c 3222 bnh nhn mc bnh v t vong 122

trng hp.

Nu cc mng bm ny khng n nh, b v nt, mu s ng cc li ti nhng

ch v nt trn cc mng bm , khin mu khng th lu thng, v hu qu l dn n

chng nhi mu c tim. Khi ln tui, c bit nam gii trn 45 tui v n trn 55 tui th

nguy c mc bnh MV rt cao. Nguy c ny cng xy ra trong gia nh c ngi mc

bnh tim sm, c th l c cha hoc anh ch em b bnh tim trc 55 tui hay c m hoc

ch em gi b bnh trc 65 tui.

Hnh 1: Cc cn bnh chnh gy t l t vong cao nht trn th gii vo nm 2011 (trong

bnh hp ng mch vnh dn u)

Mt iu ng lo ngi l bnh MV v nhi mu c tim xut hin ngy cng

nhiu nhng ngi di 50 tui, c c nhng bnh nhn di 40 tui. Cng nh trn

th gii, ti Vit Nam bnh mch vnh ang tr thnh mi nguy ln cho sc khe cng

ng v l gnh nng khng ch cho ngi bnh.

1.2 Cha tr

Bnh MV l cn bnh eo ui ngi bnh sut i v thng khng

c pht hin sm, n khi triu chng xut hin th bnh tin trin kh lu. Do vy,

cch phng bnh tt nht l phi tm sot cc yu t nguy c, kim sot chng ng thi

pht hin bnh sm v iu tr kp thi. Trong trng hp cc phng php iu tr bnh

MV nh: thay i li sng, dng thuc thch hp, nong hoc t gi MV u b

tc th m bc cu MV s l cu cnh gip bnh nhn thot khi cn bnh him ngho

ny. Phu thut bc cu MV l bin php s dng cc mch mu khe mnh t chn,

ngc, bng lm cu ni gip mu lu thng n nui vng c tim sau v tr tc nghn.

Tuy nhin, phu thut bc cu MV ch mang li hiu qu cao nht nu thc hin ng

thi im. Nu khng pht hin sm v phu thut kp thi th nhiu vng c tim b tn

thng khng hi phc v hiu qu phu thut cng gim i. Do vy, vic tm sot

pht hin v iu tr sm bnh MV l v cng quan trng.

1.3 Bnh mch vnh bnh nhn tiu ng

Qua rt nhiu nghin cu ti nhiu trung tm khc nhau ngi ta nhn thy rng

nguy c b BMV bnh nhn tiu ng tng gp 2-4 ln so vi ngi khng b tiu

ng. Trong khi t l trong dn c ni chung l 2-4 % th t l ny bnh nhn tiu

ng tng ln mt cch ng k ti 55%. T l t vong do cc bnh tim mch ni chung

ngi bnh tiu ng cng cao gp 2-6 ln so vi ngi khng b bnh.

1.4 Bnh mch vnh ph n

T l ph n mc bnh ng mch vnh tng t 2-3 ln sau thi k mn kinh. S

gia tng ny hon ton khng gii thch c nguyn nhn, nhng lng cholesterol,

chng cao huyt p v lng cht bo ng xung quanh vng bng nhiu trong giai on

ny c nh gi l nhng nguy c lm pht sinh bnh nghn ng mch vnh ph

n.

Nhng cuc nghin cu y hc v bnh tim mch trc y thng tp trung vo

n ng. Nhng gi y, cc nh khoa hc nhn ra rng c s khc bit r nt v bnh

ng mch vnh gia n ng v ph n. Chng hn, nhng ngi n ng b nhi mu

c tim thng c nhng biu hin c th nh: cn au tht ngc, khi u t ngc v

lan ra vai, c, cnh tay. ph n cng c nhng triu chng tng t, nhng cn thm

nhng du hiu ph khc nh: kh th, nng, nn ma, au hm, au lng v cm gic

mt mi. Chng nhi mu c tim ph n thng xy ra khi h lo lng hoc b cng

thng thn kinh, ngay c lc ng. Trong khi n ng, nhi mu c tim thng xy ra

khi luyn tp th dc hay trong lc ang lm vic. Do ph n khng thng xuyn c

nhng biu hin nhi mu c tim c th, nn thng chm tr trong vic iu tr v i

din vi nguy c t vong nhiu hn n ng.

Hnh 2: T l mc bnh ng mch vnh nam gii v n gii t nm 1997 n 2009

Hip hi tim M c nhng hng dn c bit gip ngn nga v iu tr ng

mch vnh ph n. Nhng hng dn ny cp n s thay i li sng, s dng

thuc men v iu tr hooc-mon ph n trong giai on mn kinh. Di y l nhng

thay i v li sng gip ngn nga bnh ng mch vnh.

- Khng nn ht thuc v trnh ht th khi thuc th ng.

- Thng xuyn luyn tp nhng bi tp vi cng va phi, khong 30 pht

/ngy nh i nhanh. Vic ny s hu ch hn cho bn nu c thc hin vo tt c cc

ngy trong tun.

n nhng thc phm c li cho tim, hn ch cc thc phm c bo v lng

cholesterol cao.

- Duy tr ch s trng lng c th v s o vng eo di 88cm.

- Trong trng hp bn c nhng tru chng ca bnh ng mch vnh, cn

trnh lo lng v mun phin.

- Khng nn ung ru.

- Trnh nhng thc phm lm tng huyt p, gim ngay vic n mn nu bn nag

b chng huyt p cao.

1.5 Bnh mch vnh ngi cao tui

Tui cao cng vi nhng thay i trong i sng kinh t, x hi nh hng

nhiu ti tp qun sinh hot ca ngi Vit Nam v c th l mt nguyn nhn quan

trng ca t l gia tng bnh MV nc ta. Hin nay c khong 9% bnh nhn ni tr

ti Vin Tim mch Vit Nam. Bnh vin Bch Mai c s ca mc bnh MV a s l

ngi cao tui.

II. TNG QUAN V BNG NONG MCH

2.1 S lc lch s v bng nong mch (balloon catheter)

Pht trin t nhng nm 1970, bng p sut cao (high-pressure balloons) c s

dng trong th thut m rng mch mu. Thng thng s dng dung dch chn sng

hoc dung dch ng trng (thng qua ng tim) nh p sut cao p mng bm vo

thnh mch v cho php dng mu hot ng bnh thng. Thu hi bng bng cch bm

chn khng cch ny cho php bng co rt li. Phng php ny c u im l t lm

vnh mch b tn thng. Hin nay, bng p sut cao c thnh mng, nh, rt ph hp

cho nhng ng mch nh vi ng knh, chiu di v hnh dng c vng phn b rng,

c bit l nhng thit k chuyn bit c hnh dng phc tp dng cho nhng ng dng

ring hay dng ph. Bng c ci thin vi thit k tng tnh linh hot ph hp cho

nhiu thit b y khoa. C nhiu ng dng nh: thit b phn gii thuc, thit b a stent,

nong mch vnh

Hnh 3: Bng nong vnh ng mch

2.2 Phn loi

C hai loi bng cn bn dng trong y khoa. Mt l bng c p sut cao, hai l

loi p sut thp. Hai loi ny c mt s c im chung.

2.2.1 Bng p lc cao (bng cng)

L loi bng khng n hi, gin n nh lc nn. Thng c lm t vt liu

khng p ng hoc t p ng (non-compliant/low-compliant material) - l vt liu gip

cho bng lu gi c hnh dng v thit k ngay khi di p sut cao. Thnh bng

loi ny mng v c bn cng gin cao. Bng cng c ng knh t 0.5-50 mm hoc

hn v c th c bt k chiu di no m vn gi c thnh mng. C th thit k bng

vi nhiu ng knh khc nhau v c u nhn t 1-90 .

Hnh 4: Bng nong p lc cao (non-compliance)

2.2.2 Bng p sut thp (bng mm)

L loi bng n hi, thng lm t silicone hoc nha, dng ng, c s dng

c nh, loi bng mm ny khng th gi c ng hnh dng khi p sut cao.

Hnh 5: Bng p lc thp (compliance)

Bng phi kim sot c kch thc v p sut m bo rng n s khng tip

tc gin n v lm v ng mch sau khi phong ta c tc nghn. Balloon compliance

l cm t m t trng thi ng knh ca bng thay i ph hp vi p sut. i vi

bng cng, n c th gin khong 5-10% vi p sut nh mc trong khi loi bng mm

c th co gin 100-600%. Sau khi gim p sut, bng mm tr li hnh dng v kch

thc ban u. Loi ny thng khng th s dng cho nhng ng dng y khoa c p

sut cao.

2.3 Vt liu bng

Loi bng u tin c ch to t polyvinyl chloride (PVC), c thnh dy cng

ging nh cc loi bng mm ngy nay. T u nhng nm 80, crosslinked polyethelene

v polyester (PET) polyethylen terephthalate c chp nhn l vt liu cho bng, v

chng dn thay th PVC.

Hnh 6: Cng thc phn t ca polyvinyl chloride (PVC)

Cui nhng nm 80, vt liu nylon ra i v polyerethane c sn xut ngay sau

. Nylon khng bn nh PET nhng li l vt liu y ha hn v n mm hn. Ngy

nay, hu ht cc loi bng mm u s dng vt liu nylon v PET. PET c u im l c

bn co gin tt, chu c p sut nh mc cao trong khi nylon th mm hn. Mt

tnh cht u vit na l kh nng truyn nhit v r v mt quang hc, chnh iu ny

lm cho bng PET ph hp vi cc tia laser, nng lng siu m v sng ngn. Mt c

im vt tri ca PET l kh nng c thnh thng mng v hnh dng rt chnh xc,

PET c thnh cc k mng, dao ng khong 5-50m.

Hnh 7: Qu trnh to vt liu polymer

Bng bng t nylon th mm hn so vi lm bng PET, mc d khng bn bng,

chnh v vy bng nylon cn phi c thnh dy hn. Tuy nhin, chnh v mm nn n d

dng gp li v rt ra khi ng thng.

Bng 1: Bng so snh cc vt liu lm bng.

2.4 Cng dng

2.4.1 Gin n

Bng gin n m vng ng mch b tt nghn (c dng trong phng php

can thip to mch qua da PTCA). Cc bng thng dng trong trng hp ny thng

c ng knh khong 2-4mm, chiu di 10-40mm v p sut nh mc khong 10-20

atm.

2.4.2 Phn phi stent (Stent delivery)

Bng cng thng c s dng t v lm gin n stent, nhm lm gim t l

ti hp v ng kn thnh ng mch. Stent, bng bc quanh ng thng v c a vo

v tr tt nghn. Bng gin n lm stent gin theo, do lm thnh mch cng m ra.

Dng p sut gin n cho php stent gin n y trc khi tng tc vi thnh

ng mch. S dng bng cng (vt liu t tng thch) gip cho stent v ng mch

khng b gin qu mc, m bo tnh an ton. Sau khi lm xp, bng c a ra khi c

th trong khi stent vn cn li.

2.4.3 Phn phi thuc (Drug delivery)

Bng cng (high-pressure balloon) rt hu ch khi dng trong phn phi thuc ti

cc v tr c bit trong c th. Mt phng php s dng bng a thuc vo v tr

tn thng hoc tc nghn l s dng 2 bng ring l trn thn ng thng phong

ta vng h tn, trong khi thuc s truyn qua khe l gia 2 bng thot ra ngoi. Khi qu

trnh thao tc thc hin xong, thuc chy ra ngoi, vng tn thng c m rng, sau

lm xp bng v co rt li.

Hnh 8: Bng vi thit k m hnh xng ch

Mt loi bng hnh dng xng ch (dog bone-shaped balloon) c th phn phi

thuc bng cch s dng phng php tng t. on cui ca bng c th bng hoc

khc ty thuc vo hnh dng mch. Khi bm bng, u cui s phong ta vt thng v

thuc thot ra ngoi thng qua cc l on gia bng. C th dng tia laser, ng thng

nng hoc cc thit b khoan to b mt l.

Mt loi bng PET thnh cc mng c th bin i thnh lp mng c nhiu ht

porous, vi ng knh mt vi m. Mt bng c th c ti hng nghn l. y l

phng php phn gii thuc c hiu qu to ln v c th kim sot ng kch thc l,

do c th iu kin ng lng thuc mc d rt nh ti v tr tn thng. t bit c

ngha i vi cc loi thuc c hay t tin . Mc d bng loi ny c nhiu vi ht

nhng cc k bn.

Hnh 9: Bng c mng a ng thuc - thuc thot ra ngoi mng bng

Thuc ph trn b mt bng v c phng thch ti v tr ch trong c th. Qu

trnh vn chuyn thuc c thc hin nh p sut, tia laser, nhit

III. MI QUAN H GIA BNH TIU NG V NG MCH

VNH

3.1 Tng quan

Danh t tiu ng hay diabetes mellitus l tn gi chung ca mt nhm bnh

nh hng n vic s dng glucose, mt loi ng trong mu hay ng huyt. L mt

nhm bnh ri lon chuyn ha cachohydrat khi hoocmon insulin ca ty b thiu hay

gim tc ng trong c th, biu hin bng mc ng trong mu lun cao.

Bnh tiu ng c th gy ra bin chng trn nhiu c quan, nhng thng gp,

gy tn km v nghim trng hn ht l bin chng tim mch. V cc c quan v b phn

trong c th u cha nhiu mch mu, cho nn tn thng mch mu s dn n tn

thng cc c quan nh mt, thn, thn kinhC s lin quan cht ch gia bnh tiu

ng v bnh tim mch. Tn sut bnh tim mch ngi b tiu ng cao gp 2-4 ln

sao vi ngi khng b. Khong 2/3 s bnh nhn tiu ng t vong l do bin chng

tim mch nh nhi mu c tim v t qu.

Hnh 10: Qu trnh gy tn thng mch mu bnh tiu ng

C nhiu nguyn nhn gii thch ti sao bnh tim mch thng gp ngi b tiu

ng. ngi b tiu ng, lng ng huyt trong mu tng cao lm tn hi n

cc mch mu, mch mu cng nh th cng d b tn thng hn. Lng ng trong

mu cao lm tng lng ng m thnh mch v lm chm dng chy ca mu. Theo

thi gian, s lng ng m c th pht trin thnh mng x va v lm dy thnh mch

mu. Nhng mng bm thnh mch c th v ra, tri dt n ni khc v lm tc

nghn. Ti ch v, cc t bo ca h min dch bt u hot ng, qu trnh ng mu

xut hin to cc mu ng, gy cn tr lu thng mu hoc tc mch t ngt.

Tn thng mch mu nh: xy ra cc nhnh ca ng mch v cc mch mu

nh hn. Cc mch mu nh b nh hng bi bnh tiu ng c th lm suy yu thnh

mch v lm cho chng phnh ln nh qu bng gi l vi phnh mch. Thnh ca nhng

mch mu ny sau b r r, gy ra tc nghn dng chy, lm gim cung cp oxy v

cht dinh dng n cc m do mch mu ny chi phi, c th dn n tn thng hoc

cht m. Tnh trng ny cng l yu t gp phn quan trng trong cc bin chng kinh

in ca bnh tiu ng nh: bnh vng mc, bnh thn v thn kinh do tiu ng.

3.2 Phng php iu tr bnh MV bnh nhn tiu ng

Khi bnh nhn tiu ng mc cc bnh lin quan n ng mch vnh, cn phi

tin hnh ti thng mch mu. Thut ng ti thng mch mu n gin ngha l hi phc

li dng mu t tim n cc b phn khc ca c th sau khi mch mu b vn cc do

mng bm. Trong trng hp lin quan n tim mch, c th thc hin th thut phu

thut bc cu, nong mch vnh v t stent.

Nong mch vnh v t stent thng c gi chung l PCI (percutaneous

coronary intervention). Cn nhiu tranh ci xoay quanh vn chn PCI hay bc cu

ng mch cho bnh nhn tiu ng. n gin bi v cha c nghin cu lm sng no

tp trung su vo vn lm sao x l cc ng mch nh i vi bnh nhn tiu ng.

Hn th na, cc bnh ng mch vnh ngi tiu ng thng khc v c tnh trng

xu hn. V d, nhng bnh nhn b tiu ng thng c mng x va phn b nhiu

hn, di hn v nh hng n nhiu ng mch, ch khng n gin ch l mt v tr tc

nghn nh nhng ngi bnh khng b tiu ng. Sau khi thc hin th thut PCI,

nhiu bnh nhn tiu ng xut hin tt nghn tr li do m so tng sinh qu mc (ti

hp). iu ny gii thch ti sao cc bnh nhn tiu ng cn phi tip tc tin hnh cc

th thut ln na.

3.2.1 Th thut bc cu

Trc y, phu thut bc cu l s la chn hng u cho bnh nhn tiu ng,

bi v cc nghin cu trc cho rng phu thut bc cu em li kh nng sng st lu

di hn so vi PCI. Nhng cc nghin cu hin nay (SCAI Statement on the BARI 2D

Trial v SCAI Statement on the SYNTAX Trail) lm thay i quan nim ny. Ngy

nay nhiu stent ph thuc xut hin trn th trng tiu th, nhiu nh nghin cu tin

tng rng PCI l cch thc tt nht.

Trong khi , theo HealthDay News ngy 15.10.2013, cc nghin cu cho thy t

l ngi cht v t nguy c tn cng tim mch ngi tin hnh th thut bc cu hn

nhng ngi thc hin nong mch vnh. Nong mch vnh ch c nh trong mt thi

gian, trong khi bnh tiu ng c tnh cht lan ta. Khng n gin ch l tn thng

mt mch mu, m h tn ton b mch.

Mt nghin cu c cng b vo 11.5.2012 th cho rng bnh nhn tiu ng

tri qua th thut bc cu loi b vng ng mch b tc nghn th sng lu hn so vi

nhng ngi chn phng php nong vnh ng mch.

3.2.2 Nong mch vnh v t stent

Cho n hin nay, kt qu lm sng khi so snh gia cc loi stent ph thuc vi

nhau v so snh stent ph thuc vi stent trn vn cn gy nhiu tranh ci khi dng cho

bnh nhn tiu ng.

Theo nghin cu ca Sripal Bangalore v cc cng s pht hnh vo 10.8.2012 th

dng stent ph thuc em li hiu qu cao (gim cc ri ro v ti thng mch mu, bao

gm hnh thnh huyt khi tr) hn so vi dng stent trn khng ph thuc. Bn cnh

, cn c s khc bit ng k khi s dng stent ph cc loi thuc khc nhau. Stent ph

everolimus th em li hiu qu cao nht (xc sut 87%), sau n stent ph sirolimus,

paclitaxel, zotarolimus (hnh 9, hnh 10).

Hnh 11: So snh nguy c nhi mu c tim v cht ca cc loi stent( tin cy 95%).

Hnh 12: So snh kh nng hnh thnh huyt khi ca cc loi stent ( tin cy 95%).

IV. NG MCH VNH PHN NHNH

4.1 Gii thiu

Tn thng ng mch vnh phn nhnh chim khong 15-20% trong tng s

bnh ng mch vnh. Tc nghn vng phn nhnh l mt trong nhng tn thng phc

tp v gy kh khn khi tin hnh tr liu bi v cn phi hi phc c khong trong ca

ng mch chnh ln ng mch nhnh. Mc tiu ca liu php iu tr l phi ti u kt

qu th thut v quan trng hn l phi t thnh cng v mt lu di nh l t l ti hp

tr thp v t gp cc vn bt li ln trong lm sng. Phng php nong mch vnh

phn nhnh bng bng em li t l ti hp cao. Mc d stent thng em li kt qu y

ha hn nhng m t l ti hp vn cn cao. Phng php s dng stent ph thuc lm

thay i cch thc tr liu kiu tn thng phn nhnh ny, tuy nhin vng ng mch

nhnh b ng li t ngt khi s dng chin lc t mt stent, bn cnh khi s dng

chin lc t hai stent th lm hnh thnh huyt khi v ti hp.

4.2 Phn loi

ng mch vng phn nhnh khc nhau ty vo v tr, ti trng ca mng bm,

gc phn nhnh, ng knh v v tr vng phn nhnh. Do tnh c trng tng vng nh

vy cho nn phi chn chin lc nong vnh ng mch tt nht, ph hp nht cho tng

kiu phn nhnh. Thng thng kiu phn loi vng ng mch phn nhnh b tn

thng ca Lefevre c s dng nht. Tuy nhin, kiu phn loi ny cng vi mt s

phn loi c khc thng gy kh nh.

Hnh 13: Kiu phn loi vng ng mch phn nhnh Lefevre

i vi kiu phn loi Medina th n gin, d nh m cung cp y thng tin

cn thit. Kiu phn loi ny m t bt k on hp no vt qu 50% lng mch trong ba

nhnh theo trnh t sau: ng mch chnh, nhnh xa v nhnh bn. K hiu 1 biu

tng c s hin din ti hp v k hiu 0 c ngha l khng c ti hp.

Hnh 14: Kiu phn loi vng ng mch phn nhnh Medina

Vng tc nghn phn nhnh kiu n gin th v tr tc nghn nm mch chnh

hay mch xa (1,1,0; 1,0,0 v 0,1,0). Liu php cha tr cng n gin hn, thng thng

s dng t mt stent trong phn ng mch chnh, v bao ph lun vng nhnh. Tuy

nhin, trong trng hp vng tc nghn phn nhnh phc tp, nh trong trng hp

1,0,1; 0,1,1 v 1,1,1 (vng tn thng nm phn nhnh) cho nn cn phi s dng thm

mt stent na mi em li hiu qu.

4.3 Stent n v stent i

Khi s dng stent, mt cu hi ln c t ra l c hay khng vic t stent c

hai vng, vng ng mch chnh v vng ng mch nhnh. Dng nh stent i th hiu

qu hn bi v phng thc ny em li kt qu sau khi t tt. Tuy nhin, vn cn nhiu

lo ngi v cc bt li v lu di nh l to huyt khi.

Bng 2: Bng so snh t l to huyt khi sau khi t mt stent v hai stent ng mch

chnh v nhnh (sau 6 thng)

4.3.1 Phng php t mt stent

i vi phng php ny, c th dng hoc khng dng bng nong mch v tr

nhnh bn.

Hnh 15: Phng php t mt stent

4.3.2 Phng php t hai stent

Nhiu k thut t stent vo vng ng mch tn thng phn nhnh c pht

trin (hnh 14). Trong , phng php T-stenting v reverse T-stenting th khng m

bo vng ng mch nhnh c ph stent hon ton. Trong k thut T-stenting, mt

stent ban u c t vo v tr ng mch nhnh, sau stent th hai t vo ng

mch chnh. i vi reverse T-stenting th ngc li, stent ban u c t vo ng

mch chnh, stent th hai s lung qua thanh chng nn ca stent ban u i qua vng

ng mch nhnh. K thut ny c s dng rng ri trong trng hp ng mch ng

mch chnh b tn thng, v stent t ng mch nhnh nhm mc ch ti u ha kt

qu cha tr. Trong trng hp ny, v tr tn thng gn ging hnh ch T, gc gia

ng mch nhnh v ng mch chnh ln hn 70 s lm cho stent nong vng tc

nghn d dng hn. Tc nghn ti hp mch nhnh thng xy ra sau khi t stent, cho

nn kh nng bao ph stent v tr ny l cc k quan trng.

Hnh 16: Cc phng php t hai stent

Ngc li, cc k thut Culotte, Crush v Simultaneous-kissing stent m bo

vng nhnh c stent bao ph hon ton. i vi k thut Culotte, stent u tin c

a vo mch nhnh bng h thng bng v ng thng, sau bng v ng thng a ra

ngoi, stent s t c phn nhnh ln phn mch chnh, sau stent th hai thng qua

thanh chng stent th nht v t mch chnh. Trong phng php Crush, c hai stent

u t cng lc mch nhnh v mch chnh, iu ny s lm san bng cc t bo nh

ln dc trong lng mch chnh. Nhc im ln nht ca cc phng php ny l nhiu

lp kim loi trong lng mch, cho nn d hnh thnh huyt khi. Vi Simultaneous-

kissing, hai stent s c t vo mch chnh v mch nhnh, k thut ny c thi gian

thc hin ngn hn v t gp cc tr ngi xu hn so vi phng php T-stenting.

Hnh 17: Phng php t stent th hai thng qua thanh chng stent th nht

4.4 Kissing balloon

Kissing balloon (KS) l k thut chuyn dng u tin dng nong mch vng

phn nhnh v vn tip tc ng vai tr quan trng cho n nay. Kissing balloon c hai

nhim v chnh: (1) tin phong m rng v sa cha tn thng lng ng mch v (2)

gin n stent. Tuy nhin, i vi nhng mng bm canxi qu phc tp v nguy him th

khng dng k thut ny. Quyt nh chn kissing balloon cn ph thuc vo nhiu yu

t nh: kiu thit k stent, vt liu bng (tng thch hay khng tng thch), ng knh

bng, v tr tn thng.Thng thng, p sut dng bm bng nm trong khong 8-

14 atm v p sut bm bng mch nhnh nh hn p sut bm bng mch chnh.

Hnh 18: Phng php m rng vng tt nghn v tr mch phn nhnh bng kissing

balloon.

Hnh 19: Kissing balloon trong trng hp dng hai stent

Trong qu trnh t hai stent vo vng mch phn nhnh, s xy ra mt s tip xc

(kiss) nh gia bng-bng, bng-stent, cho nn ngi ta gi phng php dng bng t

stent ny l kissing balloon.

V. NGHIN CU QUY TRNH NH GI P SUT N NH

MC CA BNG CA STENT THNG

Mi loi bng s c bm t ti ng knh danh ngha (nominal) ca ring

tng loi. p sut bng dao ng t p sut danh ngha ti p sut n nh mc. Tt c

cc bng u c th gin trn kch thc danh ngha vi p sut cao hn p sut danh

ngha.

p sut n nh mc l p sut cc i m ti bng khng b v. Trong kim

tra in vitro, 99.9% bng s khng n di hoc ti p sut n nh mc vi tin cy

95%. p sut n nh mc phi c tnh ton v dn nhn. p sut bng khng c

vt qu p sut n nh mc.

H thng bng - ng thng cn phi c kim tra v nh gi cc ch tiu nh p

sut danh ngha v p sut n nh mc m bo an ton v hiu qu trong khi s

dng. Bng phi th hin v hot ng theo ng thit k khi c bm phng ln v

khng xut hin nguy c r r hoc n.

5.1 Dng c, thit b

Thit b dng trong kim tra phi c kh nng kim sot chnh xc v th tch, p

sut, tc chy, gim thiu sai lch khi thc hin lp li. Thit b phi o v v hoc th

hin biu p sut v th tch ca bng nong mch, o lng khong thi gian bm

phng v x hi xp bng.

Cc thit b, dng c gm c:

B nc (c th cha th tch ln ti 3.5l)

My m thi gian

Dung dch bm

My kim tra v tr r r

ng bm hoc l thit b tng ng ( chnh xc 5%, duy tr c p lc

bm, tun th theo tiu chun ISO 594-1 hoc ISO 594-2).

Hnh 20: Bn nc (c th kim sot c nhit )

5.2 Quy trnh thc hin

Quy trnh kim tra bng nong thng c thc hin bng cch s dng kt hp

gia kim tra p sut v kim tra su chn khng xc minh qu trnh bm phng/lm

xp bng, thng tin v ng cong gin n.

Dng phng php Crescent Burst Tester tnh (ISO 10555)

Quy trnh:

a. u tin, lm y b nc bng nc sch, iu chnh nhit nc n

nhit 37OC (gi tr nhit c th sai lch 0.2)

b. Tip theo, cho dung dch bm vo bng bng ng bm (Lu , trong bc

thao tc ny trnh lm h hi bng, nu c lp tc quay li bc a vi bng

khc)

c. Nhn chm ton b bng vo bn nc

d. Gi nguyn bc c t nht trong vng 2 pht

e. Thi phng bng t p sut ban u cho n khi ti p sut m bng n

(ghi nhn li p sut bng v)

f. Tin hnh tng t t bc a n bc e i vi cc bng khc m bo

c ngha v mt thng k

g. Thc hin tnh ton p sut n nh mc ( chnh xc ng tin cy).

Hnh 21: Bng v khi vt qua p sut n nh mc

Hnh 22: M hnh kim tra p sut n nh mc ca bng

5.3 Kt qu v tho lun

Thc hin kim tra p sut n nh mc ca 10 bng stent trn, kt qu thu c

th hin qua bng bn di.

Bng 3: Bng kt qu o p sut n nh mc 10 bng stent trn

H thng bng stent trn MicroDriver

STT 1 2 3 4 5 6 7 8 9 10

ng knh bng (mm)

2.25 2.25 2.26 2.25 2.25 2.25 2.26 2.25 2.25 2.25

p sut danh nh (atm)

13 13 12.9 13 12.9 13 13 13 13 -

p sut n nh mc (atm)

21 21 21 21 21.1 21 21 21 21 -

Nhn xt: Ngoi mu bng s 10 khng c kt qu v k thut vin kim tra lm

h bng ngay giai on bm cht lng, 9 mu cn li u cho kt qu o p sut n nh

mc l 21 atm. Nh vy, bng phn phi stent trn u cho p sut n nh mc l nh

nhau v nm trong gii hn thit k.

Ngoi ra, quy trnh kim tra cng tin hnh nh gi p sut n nh mc cc loi

bng c ng knh khc nhau, bng 4 th hin kt qu thu c.

Bng 4: Kt qu o p sut n nh mc ca bng lm t vt liu khng tng thch

ng knh bng

(mm)

Chiu di bng (mm)

20 30 40 60 80 100 120 150 180 200

3.0

24 ATM

4.0

5.0

6.0 22 ATM

7.0 20 ATM 18 ATM

8.0

9.0 18 ATM

10.0 14 ATM

12.0

Mt vn cn ch l kim tra thng s p sut phi i i vi kim tra chiu

di bng, c bit l khi bng gin n di p sut cao, thay i chiu di bng cng nh

hng n thnh mch, n v tr gn hoc xa vng tn thng cn cha tr.

Hnh 23: Chiu di bng thay i khi thay i p sut (a) v chiu di thay i ph thuc

vo mi loi stent (b)

Nhn xt: Khi thc hin kim tra p sut n nh mc ca cc loi bng c ng

knh t 3mm n 12mm v chiu di t 20mm n 200mm. Kt qu cho thy bng c p

sut n nh mc nm trong gii hn cho php ty thuc vo ng knh v kch thc

ca mi loi bng. Bn cnh c th thy rng bng c ng knh cng ln th p sut

n nh mc cng gim, tuy nhin y v s lng bng kim tra cha ln, cho nn

cn phi tin hnh kim tra vi s lng ln c ngha v mt thng k. Ngoi ra,

mt vn cn c quan tm l bng c cng kch thc nhng khi m rng cho cc

loi stent khc nhau th p sut n nh mc cng khc nhau. iu ny cho thy s nh

hng ca thit k stent ln p sut n nh mc.

VI. KT LUN

(1) S hi ha ca h thng phn phi stent ng vai tr quan trng n hiu qu

ca th thut. Ngoi vic m bo tnh tng thch sinh hc ca stent thng cng cc

tiu chun khc, nht thit phi thc hin nh gi p sut n nh mc ca bng. y l

mt trong nhng tiu chun m bo tnh an ton v hiu qu khi t stent. ngha

ca vic phn tch p sut n nh mc ca bng gip cho cc bc s iu tr bit thng

tin cn thit thc hin t stent v gim st kt qu tt hn.

Quy trnh thc hin:

a. u tin, lm y b nc bng nc sch, iu chnh nhit nc n nhit

37OC (gi tr nhit c th sai lch 0.2)

b. Tip theo, cho dung dch bm vo bng bng ng bm (Lu , trong bc thao

tc ny trnh lm h hi bng, nu c lp tc quay li bc a vi bng khc)

c. Nhn chm ton b bng vo bn nc

d. Gi nguyn bc c t nht trong vng 2 pht

e. Thi phng bng t p sut ban u cho n khi ti p sut m bng n (ghi

nhn li p sut bng v)

f. Tin hnh tng t t bc a n bc e i vi cc bng khc m bo c

ngha v mt thng k

g. Thc hin tnh ton p sut n nh mc ( chnh xc ng tin cy).

(2) Vic tm ra p sut n nh mc ca mi h thng phn phi ph thuc vo

vt liu (tng thch v khng tng thch) v cng ngh ch to bng. Bng cch bm

nc vo trong bng ri t vo trong bn nc 37 2OC, bt u bm bng t p sut

ban u cho n p sut m bng n, ghi nhn li kt qu v tin hnh thc hin lp li

(c ngha v mt thng k), tnh ton kt qu. Vic nh gi p sut n nh mc ca

bng l mt trong nhng ch tiu nh gi mc an ton v hiu qu khi s dng h

thng phn phi stent bng bng vo ng mch, cc nh gi ny phi thc hin theo

quy trnh nghim ngc m bo tt nht mc chnh xc, trnh sai st.

TI LIU THAM KHO

1. Caixeta A, et al. Clinical follow-up 3 years after everolimus- and paclitaxel-

eluting stents. JACC Cardiovasc Interv. 2010;3(12):12208.

2. Shabalovskaya SA. On the nature of the biocompatibility and on medical

applications of NiTi shape memory and superelastic alloys. Biomed Mater Eng

1996;6(4):267-89.

3. Nguyen KT, Su SH, Sheng A, Wawro D, Schwade ND, Brouse CF, et al. In

vitro hemocompatibility studies of drug-loaded poly-(L-lactic acid) fibers.

Biomaterials 2003;24:5191-201.

4. Matthews IP, Gibson C, Samuel AH. Sterilisation of implantable devices. Clin

Mater. 1994;

5. Lichtenfels, Frankini, & Cardozo. (2011). Stent graft infection. J. Vasc. Bras.

6. Sigwart et al. (1992). Coronary stents. 45-55 & 57-77.

7. Stent Materials and Manufacturing: Requirements and Possibilities /

Opportunities. ASM Materials & Processes for Medical Devices Conference

8-10 Sept. 2003, Anaheim, CA.

8. Caixeta A, et al. Clinical follow-up 3 years after everolimus- and paclitaxel-

eluting stents. JACC Cardiovasc Interv. 2010;3(12):12208.

9. Serruys PW, et al. A bioabsorbable everolimus-eluting coronary stent system

(ABSORB): 2-year outcomes and results from multiple imaging

methods. Lancet. 2009;

10. MedMarket Diligence report #C245, worldwide market for drug-eluting, bare

and other coronary stents. 2009;20082017.

11. In: Rutala WA, editor. Association for Professionals in Infection Control and

Epidemiology. DC.: Washington; 2001.

12. ISO TC 198. ISO/Draft International Standard, Aseptic processing of health

care products, Part 7: Alternate processes for atypical medical devices and

combination devices.

13. http://www.medscape.org/viewarticle/501397

14. http://www.bmj.com/content/345/bmj.e5170

A IV IV.1 76

Documents

Transcript of A IV IV.1 76