Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_3612_Библиотеки_им_академика_М_И_Перельмана
.pdf
Key Questions in CONGENITAL CARDIAC SURGERY
13 What are the echocardiographic features of atrial
septal defects?
Echocardiography can be used to definitively diagnose the type of
•
anatomical defect with 2D and 3D images (Figure 9).
Colour-flow Doppler is used to quantify the shunt across the atrial
•
septum (Figure 10).
ps`
AB
i^
lлнбмг=
лЙЕмеЗмг=
ЗЙСЙЕн
o^=
460
o^ss=
fs`
C
fs`
o^=
lлнбмг=йкбгмг=ЗЙСЙЕн
i^
Figure 9. Transthoracic echocardiography, with: A) 3D images demonstrating
a large ostium secundum defect with a multi-fenestrated fossa membrane;
and 2D images demonstrating: B) an ostium primum defect, with alignment of
both atrioventricular valves on the same plane, which is typical of a partial
atrioventricular septal defect; and C) an inferior sinus venosus defect. SVC =
superior vena cava; IVC = inferior vena cava; RA = right atrium; LA = left atrium;
LAVV = left atrioventricular valve; RAVV = right atrioventricular valve.
i^ss=
13 Atrial septal defects
Данная книга находится в списке для перевода на русский язык сайта https://meduniver.com/
o^
Figure 10. Transoesophageal echocardiogram demonstrating
a moderate-large left-to-right shunt across the interatrial
septum on colour-flow Doppler. RA = right atrium; LA = left
atrium.
461
Echocardiography can also demonstrate the haemodynamic
•
consequences of the defect, including:
a) right ventricular chamber size and function (degree of dilatation
and dysfunction) (Figure 11);
b) right atrial enlargement;
c) pulmonary artery dilatation;
d) tricuspid regurgitation.
It is also important to identify any associated cardiac abnormalities,
•
including:
a) cleft mitral and mitral regurgitation (in ostium primum defects);
b) persistent left-sided superior vena cava (in coronary sinus
defects);
c) anomalous pulmonary venous drainage (in sinus venosus
defects) (Figure 12).
Key Questions in CONGENITAL CARDIAC SURGERY
AB
os=
is=
os=
s=
i
Figure 11. Parasternal: A) long-axis; and B) short-axis transthoracic
echocardiographic images demonstrating right ventricular dilatation,
secondary to volume overload in a patient with an ostium secundum defect.
RV = right ventricle; LV = left ventricle.
462
ps`
orms
i^
páåìë
o^=
оЙезлмл
ЗЙСЙЕн
Figure 12. Doppler echocardio-
graphy demonstrating flow across the
superior cavo-atrial junction, inflow
from an anomalous right upper
pulmonary vein (RUPV) into the right
atrium and a shunt across a sinus
venosus defect. SVC = superior vena
cava; RA = right atrium; LA = left atrium.
13 Atrial septal defects
Данная книга находится в списке для перевода на русский язык сайта https://meduniver.com/
14 Describe the bubble test (Figure 13)
Sterile saline is agitated by passing it between two syringes to
•
produce tiny bubbles.
Following intravenous injection of the saline, echocardiographic
•
images of the left and right atrium are monitored.
A
_мДДдЙл=бе=o^Los
is=
i^
B
_мДДдЙл=бе=i^
C
_мДДдЙл=бе=is
Figure 13. Bubble test demonstrated
on serial transthoracic apical fourchamber images: A) the right atrium
(RA) and ventricle (RV) are filled with
bubbles; B) during a Valsalva
manoeuvre, the bubbles fill the left
atrium (LA) first; and then C) the left
ventricle (LV).
463
Key Questions in CONGENITAL CARDIAC SURGERY
If the atrial septum is intact, the bubbles should remain on the right
•
side.
Bubbles within the left atrium indicate a communication between the
•
atria, suggestive of an atrial septal defect.
15 What are cardiac catheterisation findings of atrial
septal defects?
Routine cardiac catheterisation is unnecessary in children with a
•
previously diagnosed uncomplicated atrial septal defect.
For patients with pulmonary hypertension, associated congenital
•
abnormalities or age over 40 with suspected coronary artery disease,
cardiac catheterisation is an important component of the surgical
work-up.
Oxygen saturation measurements in the systemic and pulmonary
•
circulations will reveal a step-up in right ventricular and pulmonary
artery oxygen saturations (Table 1).
464
Table 1. Cardiac catheterisation data demonstrating a step-up in right atrial
(RA) oxygen saturations in an adult patient with an ostium secundum defect.
SVC = superior vena cava; MPA = main pulmonary artery; LPA = left pulmonary
artery; FA = femoral artery; RUPV = right upper pulmonary vein; BCV =
brachiocephalic vein; IVC = inferior vena cava; EDP = end-diastolic pressure.
páíÉ
SVC
RA
MPA
LPA
FA
RUPV
BCV
High SVC
Low SVC
Mid RA
Low RA
High RA
Low IVC
High IVC
mкЙллмкЙ ~еЗ=зсуЦЙе=л~нмк~нбзе=З~н~
p~í
B
65
96
79.3
78.8
93
97.4
63.9
64.3
61.7
96
76.3
67.7
68.8
68.2
~
ããeÖ
7
6.5
î
ããeÖ
pулнздбЕ
ггeЦ
82
125
aб~лнздбЕ
ггeЦ
26
65
bam
ããeÖ
75
jÉ~å
ããeÖ
28
13 Atrial septal defects
Данная книга находится в списке для перевода на русский язык сайта https://meduniver.com/
High oxygen saturations in the superior vena cava may indicate the
•
presence of a sinus venosus defect.
Cardiac catheterisation also allows the size of the shunt to be
•
quantified by calculating the shunt fraction.
16 How do you calculate the shunt fraction (Qp:Qs)
(Figure 14)?
Using the Fick principle:
•
Flow = O2consumption
arteriovenous O2concentration difference
Flow = O2consumption
(arteriovenous O2sats difference x Hb x 1.34 x 10)
Pulmonary flow = O2consumption
[(PV sats - PA sats) x Hb x 1.34 x 10]
465
Systemic flow = O2consumption
[(Ao sats - RA sats) x Hb x 1.34 x 10]
As O2consumption and Hb are the same in both equations
Pulmonary flow: systemic flow ratio (shunt ratio)
Qp:Qs = (Ao sats - RA sats)
(PV sats - PA sats)
RA sats = (3 x SVC sats) + (1 x IVC sats)
4
PV = pulmonary vein; PA = pulmonary artery; Ao = aorta; RA = right
atrium; SVC = superior vena cava; IVC = inferior vena cava; Hb =
haemoglobin; sats = oxygen saturations.
Key Questions in CONGENITAL CARDIAC SURGERY
466
VVB
VVB
UOB
UOB
VVB
VVB
SQB
SUB
Figure 14. Shunt calculation based on the Fick principle. RA sats = ([3 x
64] + [1 x 68]) / 4 = 65%. Measured PA saturations = 82%. Measured PV
saturations = 99%. Assuming aortic and PV saturation are equal, the
Qp:Qs shunt in this patient will be: (99 - 65) / (99 - 82) = 34 / 17 = 2:1.
17 What are the therapeutic options for a patient with an
atrial septal defect?
Conservative management:
•
a) infants with an ostium secundum defect <8mm (as 66% close
within 18 months);
b) adults with a Qp:Qs ratio of <1.5;
c) patients with severe pulmonary vascular resistance, shunt
reversal and fixed pulmonary hypertension (pulmonary artery
systolic pressure [PASP] >60mmHg, pulmonary vascular
resistance [PVR] >12 WU).
Medical therapy — to optimise patients with atrial arrhythmias and
•
right ventricular volume overload prior to intervention.
13 Atrial septal defects
Данная книга находится в списке для перевода на русский язык сайта https://meduniver.com/
Percutaneous closure.
•
Surgery.
•
18 What are the indications for therapeutic closure of an
atrial septal defect?
A Qp:Qs ratio of >2.
•
Atrial arrhythmia.
•
Reversible pulmonary hypertension.
•
Right ventricular dysfunction.
•
Patent foramen ovale in patients with a demonstrated right-to-left
•
shunt (by saturations or bubble study) and recurrent paradoxical
cerebral emboli.
19 What are the contraindications for therapeutic closure
of an atrial septal defect?
Asymptomatic patient with a clinically insignificant atrial septal defect
•
(Qp:Qs <1.5).
Shunt reversal with fixed pulmonary hypertension (PASP >60mmHg,
•
PVR >12 WU).
467
20 What are the principles of device closure for an atrial
septal defect (Figure 15)?
Device closure is only suitable in patients with:
•
a) ostium secundum defects (within the fossa ovalis);
b) 5mm rim from the defect to the valves and major veins;
c) defect <40mm in size.
General anaesthesia or local anaesthesia with sedation.
•
Femoral venous access with fluoroscopic and transoesophageal
•
guidance.
The diameter of the defect is measured both by echocardiography
•
and sizing balloon.
Deployment of the occluder device.
•
There are several types of occluder devices available, including:
•
a) AMPLATZER™ Septal Occluder (St Jude Medical, St Paul,
MN, USA) (Figure 16);
b) CardioSEAL®Septal Occlusion System (NNMT Medical,
Boston, MA, USA);
c) HELEX®Septal Occluder (Gore, Flagstaff, AZ, USA).
Key Questions in CONGENITAL CARDIAC SURGERY
AB
CD
468
EF
Figure 15. Device closure of an atrial septal defect. Transoesophageal
echocardiographic images demonstrating: A) an ostium secundum
defect with a large shunt; B) measurement of the size of the fossa ovalis
membrane and assessment of the margins of the defect for positioning of
the device; C) partial deployment of the device; and D) complete
deployment resulting in a stabilised disc position with no residual shunt
demonstrable on colour flow Doppler. Fluoroscopic images
demonstrating: E) measurement of the defect diameter by the balloon
catheter; and F) deployment of the device.
13 Atrial septal defects
Данная книга находится в списке для перевода на русский язык сайта https://meduniver.com/
Figure 16. AMPLATZER™ atrial septal occluder in an
explanted heart.
Medical, Inc. or its related companies. Reproduced with
permission from St. Jude Medical™, © 2013. All rights
reserved.
AMPLATZER is a trademark of St. Jude
21 What are the surgical approaches for an atrial septal
defect (Figure 17)?
Median sternotomy.
•
Submammary anterior thoracotomy.
•
Posterolateral thoracotomy.
•
Robotic or video-assisted minimally invasive thoracoscopic access.
•
Skin incision
Chest wall incision
4th intercostal space
Sternum
I
II
III
IV
V
VI
469
Figure 17. Common surgical approaches to repair an ASD.
Соседние файлы в папке Библиотека им академика М.И. Перельмана