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_3651_Библиотеки_им_академика_М_И_Перельмана
.pdf
6 Case 6
https://t.me/medicina_free
89
Fig. 6.2 A 24-hour Holter ECG showing a high ventricular arrhythmia burden, with isolated, coupled, and runs of
mostly monomorphic PVC, representing 37% of the total number of QRS complexes/24h
90
https://t.me/medicina_free
R. Le Bouar et al.
Fig. 6.3 Left panel: M mode echocardiography showing
an end-systolic diameter of the LV of 57mm, with mild
systolic LV dysfunction, LV EF of 46% (Teichholz).
Fig. 6.4 Left panel: Angiography image of the left coronary artery showing severe stenosis (70–90%) of the left
anterior descending coronary artery in its midpart (red
arrow). Right panel: LAD coronary artery after percuta-
Right panel: Apical four-chamber view showing mild
systolic LV dysfunction, LV EF of 46% (single-plane
Simpson method)
neous transluminal angioplasty and stent implantation in
its midpart (red arrow), showing no residual stenosis at
this level
6 Case 6
https://t.me/medicina_free
91
Fig. 6.5 Left panel: Cardiac MRI image in parasternal
short-axis view showing late enhancement at the level of
the interventricular septum (red arrow). Right panel:
Apical four-chamber view showing late enhancement at
the level of the interventricular septum and at the level of
the LV apex (red arrow)
Figure 6.1 explained. A 12-lead ECG showing sinus rhythm with a heart rate of 60bpm,
QRS axis at −90°, LAFB, RBBB, isolated
monomorphic PVC.These PVCs have a “unique
R” morphology in leads II, III, aVF, and I, QS in
leads aVL, aVR, with a precordial transition in
lead V3, compatible with an outow tract origin. Of note, the duration of the PVC QRS complex is 145ms. The transition from V2 to V3 is
abrupt.
92
https://t.me/medicina_free
R. Le Bouar et al.
A catheter ablation procedure was offered and
accepted by the patient.
Electrophysiological Study andRF
Catheter Ablation Procedure
The ablation procedure was performed under
local anesthesia and conscious sedation. Vascular
access was obtained using the modied Seldinger
technique, under Doppler ultrasound guidance. A
6F bipolar non-steerable catheter (Viking, Boston
Scientic®) was introduced in a 6F 20cm vascular sheath and was subsequently advanced via the
right common femoral vein up to the right ventricular apex. A Biosense Webster® SmartTouch
SF open-irrigated 3.5mm tip with double curve
D/F was used as the roving/ablation catheter,
which was introduced in a 9F 20 cm vascular
sheath at the level of the right common femoral
vein and advanced at the level of the right ven-
tricle. The CARTO ® 3 electro-anatomic mapping system (Biosense Webster, Johnson &
Johnson) was used to guide mapping and ablation
of the PVC.
Ventricular pacing was carried out at twice the
diastolic threshold using the EP-4™ Cardiac
Stimulator (Abbott®) system. Surface ECG and
intracavitary ECGs were recorded by the
WorkMate Claris™ System (Abbott®).
Given QRS transition of the PVC in lead V3,
mapping of the PVC was commenced in the
RVOT.
An anatomical map of the RVOT was initially
created. Next, an activation map of the RVOT
during the frequent PVCs was created. This
showed the presence of a wide area of early activation at the level of the posterior RVOT, with the
earliest bipolar local electrogram not preceding
the surface QRS (Fig.6.6). The unipolar electrogram at the site of the earliest activation pattern
had a “rS” pattern.
Fig. 6.6 Left panel: CARTO image of the RVOT in a
LAO 138°, cranial 6° view showing the activation map
during PVC with the earliest endocardial activation at the
level of superior posterior and septal part of the RVOT
(red area). Right panel: A 12-lead ECG together with the
earliest ventricular electrogram recorded by the distal
electrode of the ablation catheter (Map 1–2) in the RVOT
6 Case 6
https://t.me/medicina_free
A pacemap was subsequently created by pacing from the distal electrode of the roving/ablation catheter at a xed coupling interval of
600ms in several areas of the RVOT, with emphasis on the large area of the earliest activation during the PVCs. The PASO module of the CARTO
system was used to compare the resulting 12-lead
ECG during local pacing with the morphology of
the PVC. The best superposed concordance of
88% was observed at the level of the high septal
part of the RVOT (Fig.6.7).
Question 2: Is this a good ablation site?
A. Yes. The activation map indicates a
focal mechanism originating from this
site.
B. Yes. The pacemap indicates a correla-
tion of almost 90% between the sponta-
93
neous PVC and the local pacing- induced
QRS morphology.
C. No. The earliest activation in the RVOT
does not precede the beginning of the
QRS.
D. No. The local unipolar electrogram
recorded by the distal electrode of the
roving/mapping catheter has an “rS”
pattern.
E. No. The pacemap indicates a correlation
of 88% between the spontaneous PVC
and the local pacing- induced QRS morphology, and this is not good enough.
Figure 6.6 explained. CARTO image of the
RVOT in a LAO 138°, cranial 6° view showing
the activation map during PVC with the earliest
endocardial activation at the level of superior
posterior and septal part of the RVOT (red area).
Fig. 6.7 CARTO image in LAO 145° caudal 7°showing
the activation map of the RVOT during PVC.The roving/
ablation catheter in contact with the postero-septal wall in
its superior part, at the level of the earliest endocardial
activation during PVC.The pacemap performed at this
particular site (left side of the image, yellow star) reproduces a QRS morphology with a concordance of only
88% compared to that of the PVC
94
https://t.me/medicina_free
R. Le Bouar et al.
It is worth noting that the earliest endocardial
activation does not precede the beginning of the
QRS complex on 12-lead ECG (right panel).
Also, the earliest endocardial activation (red
color) is recorded in the RVOT in a large area.
This, together with the earliest local activation
that begins after the QRS onset should raise suspicions about the RVOT being a suboptimal target for RF ablation.
Figure 6.7 explained. CARTO image in LAO
145° caudal 7° showing the activation map of the
RVOT during PVC.The roving/ablation catheter
in contact with the postero-septal wall in its superior part, at the level of the earliest endocardial
activation during PVC.The pacemap performed
at this particular site (left side of the image, yellow star) reproduces a QRS morphology with a
concordance of only 88% compared to that of the
PVC, which is a suboptimal ablation criteria. RF
application at this level determined the disappearance of the PVC, but with reappearance
1min after.
The activation map of the RVOT during the
PVCs identied a possible ablation site, at the
level of the posterior RVOT, where the local
bipolar electrogram did not precede the QRS
onset on the surface ECG. Also, the unipolar
electrogram at the site of the earliest activation
pattern had a “rS” pattern, not a desirable “QS”
pattern, suggesting a suboptimal ablation site.
Access to the basal aorta was obtained by was
puncturing the right common femoral artery
using the modied Seldinger technique, under
Doppler ultrasound guidance. The Biosense
Webster® SmartTouch SF catheter was introduced in a 9F 20cm vascular sheath and was subsequently advanced via the external and then
common iliac artery, descending aorta, aortic
arch, and the ascending aorta up to the level of
the aortic cusps.
An anatomical map of the aortic cusps, sinus
of Valsalva, and the basal ascending aorta was
initially created. During mapping of the junction
of the right and left coronary cusps, before any
RF delivery was performed, disappearance of the
PVC was noticed, likely due to a “catheter bump”
at this level. Therefore, no activation mapping
was possible at this point of the procedure.
Question 4: What would be the next best
step at this point of the procedure?
A. Terminate the procedure and retry
another day, after reappearance of
PVCs.
B. Terminate the procedure and offer long-
term anti-arrhythmic drugs.
C. Perform a pacemap to identify the origin
of the PVCs.
D. Wait 20min for the PVCs to reappear
and perform activation mapping.
E. Administer isoprenaline.
Question 3: What would be the next best
step at this point of the procedure?
A. Increase power to 40W and reapply RF
energy at this site.
B. Map the LVOT region.
C. Map the coronary cusp region.
D. Terminate the procedure and suggest
anti-arrhythmic medication.
E. I don’t know.
Given the suboptimal ablation criteria in the
RVOT, mapping of the aortic root was considered
the next best step of the procedure.
A waiting period of 20min was considered the
next best step at this point of the procedure.
However, no PVCs appeared during this phase.
Question 5: What would be the next best
step at this point of the procedure?
A. Terminate the procedure and retry
another day, after reappearance of
PVCs.
B. Terminate the procedure and offer long-
term anti-arrhythmic drugs.
6 Case 6
https://t.me/medicina_free
95
C. Terminate the procedure since no reap-
pearance of PVCs indicates procedural
success.
D. Perform a pacemap to identify the origin
of the PVCs.
E. Administer isoprenaline.
Next, isoprenaline was administered, but
without appearance of any PVCs.
Question 6: What would be the next best
step at this point of the procedure?
A. Terminate the procedure and retry
another day, after reappearance of
PVCs.
B. Terminate the procedure and offer long-
term anti-arrhythmic drugs.
C. Terminate the procedure since no reap-
pearance of PVCs indicates procedural
success.
D. Perform a pacemap to identify the origin
of the PVCs.
E. I don’t know.
Creation of a pacemap of the aortic cusps was
considered the next best step at this point of the
procedure. This was subsequently performed,
and this found a concordance of 97% between the
PVC morphology and the locally induced QRS
morphology at the level of the junction of the
right and left coronary cusps, at the site where
mechanical disappearance of the PVCs was
noticed (Fig.6.8).
A few isolated spontaneous PVCs were
observed at this point of the procedure. This
Fig. 6.8 CARTO image in LAO 124° cranial 13° showing the RVOT (left side of the image in purple) and the
base of the aorta (right side of the image), with the roving/
ablation catheter at the level of the junction of the left and
right aortic cusp and the base of the left ventricle underneath the base of the aorta (lower right part of the image).
The pacemap in the left aortic cusp performed at the level
of the earliest endocardial activation site (yellow star)
reproduces a QRS morphology with a concordance of
almost 97% compared to that of the PVC (optimal ablation criteria)
96
https://t.me/medicina_free
allowed performance of an activation map
(Fig. 6.9). The bipolar electrode of the roving/
ablation catheter situated at the level of the left
sinus of Valsalva recorded a local ventricular
electrogram that preceded the surface QRS by
20 ms. The local unipolar electrogram had a
“QS” aspect at this specic site.
Question 7: Is this a good ablation site?
A. Yes. The earliest bipolar local electro-
gram precedes the surface QRS by
20ms and this should be enough for a
successful site.
B. Yes. The activation map of the right cor-
onary cusp indicates a focal mechanism
originating from this site.
C. Yes. The local unipolar electrogram
recorded by the distal electrode of the
R. Le Bouar et al.
roving/mapping catheter has a “QS”
pattern.
D. All of the above.
E. No. The earliest endocardial activation
in the LVOT precedes the beginning of
the QRS complex by only 20 ms, and
this is usually not good enough for a
successful lesion.
RF delivery at the site of earliest endocardial
activation with a target power of 25 W (with
energy titration from 15 to 25 W) and a target
ablation index of 350 was applied (Fig. 6.10),
with prompt disappearance of PVCs.
After a waiting period of 30min, IV isoprena-
line was administered as continuous infusion,
with no PVC observed.
Fig. 6.9 Right panel: CARTO image in LAO 120°
showing the activation map of the RVOT (left side of the
image) and of the base of the aorta (right side of the
image). The earliest local endocardial activation is
recorded at the level of the junction of the left and right
coronary cusp. Left panel: Local electrogram recorded
during PVC by the roving/ablation catheter at the level of
the left coronary cusp (Map 1–2). The bipolar electrogram
precedes the onset of the QRS by 20ms and the local unipolar electrogram has a “QS” aspect
6 Case 6
https://t.me/medicina_free
Fig. 6.10 CARTO
image in LAO 113°
cranial 24° showing the
activation map of the
aortic root with
superposed RF ablation
lesions
97
There were no complications related to the
procedure.
The 12-lead ECG post-ablation is shown in
Fig.6.11.
The patient was discharged from the hospital
48 h later.
The result of the 24-h Holter ECG performed
2 months after the RF ablation procedure is
shown in Fig.6.12. It demonstrated the presence
of 572 PVC of two morphologies, representing
0.6% of the total number of QRS complexes
recorded in the 24-h interval.
Transthoracic echocardiography performed
2 months after the ablation procedure demonstrated an increase in the LVEF% from 46 to 52%
post-ablation (Fig.6.13).
Answers
Question 1: E. Junction of the left and
right coronary cusp.
Question 2:
C. No. The earliest endocardial activation in the RVOT does not precede the
beginning of the QRS complex.
D.No. The local unipolar electrogram
recorded by the distal electrode of the
roving/mapping catheter has an “rS”
pattern.
E.No. The pacemap indicates a correlation of 88% between the spontaneous PVC and the local pacing-induced
QRS morphology, and this is not good
enough.
Question 3: C. Map the coronary cusp
region.
Question 4: D.Wait 20min for the PVCs
to reappear and perform activation
mapping.
Question 5: E.Administer isoprenaline.
Question 6: D. Perform a pacemap to
identify the origin of the PVCs.
Question 7: D.All of the above.
98
https://t.me/medicina_free
Fig. 6.11 A 12-lead ECG after the RF ablation procedure showing sinus rhythm with a heart rate of 64bpm, QRS axis
at −90°, LAFB, RBBB, and absence of PVC
R. Le Bouar et al.
Fig. 6.12 A 24-hour Holter ECG performed 2months after the RF ablation procedure showing a very low arrhythmia
burden
Соседние файлы в папке Библиотека им академика М.И. Перельмана