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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_3651_Библиотеки_им_академика_М_И_Перельмана
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Fig. 10.1 A 12-lead ECG showing sinus rhythm with a heart rate of 72bpm, QRS axis at +45°, two isolated PVC of
different morphologies (star), and incomplete RBBB
R. Le Bouar et al.
Fig. 10.2 Left panel: Transthoracic echocardiography image showing a non-dilated left ventricle, with preserved LV
systolic function. Right panel: Apical four-chamber view showing a non-dilated left and right atrium
effort, with LBBB morphology, superior or inferior axis.
Given the right ventricular dilation found at
transthoracic echocardiography, a cardiac MRI
was performed, which demonstrated an enlarged
RV, with dyskinesia of the basal wall, with late
gadolinium enhancement in this area, localized
aneurysm of the RV inferior and lateral wall, preserved RV EF%, arguments in favor of arrhythmogenic cardiomyopathy (Fig.10.3).
Question 1: What is the most likely cause
of the patient’s syncope?
A. Sustained monomorphic ventricular
tachycardia.
B. Polymorphic ventricular tachycardia.
C. Supraventricular tachycardia.
D. Paroxysmal AV block.
E. Vasovagal syncope.
ab
cd
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Fig. 10.3 Panel A: Cardiac MRI image (cine SSFP four-
chamber view) showing an enlarged right ventricle, with a
ratio of end-diastolic diameter of RV/end-diastolic diameter of LV>1. Panel B: cine SSFP short-axis view also
Given the suspicion of arrhythmic syncope in
the context of newly diagnosed arrhythmogenic
cardiomyopathy, an electrophysiological study
was subsequently scheduled and performed.
showing dilation of the right ventricle, a criteria in favor
of arrhythmogenic cardiomyopathy. Panel C: Localized
aneurysm of the RV inferior wall (red arrow). Panel D:
Localized aneurysm of the lateral RV wall
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
Electrophysiological Study andRF
Catheter Ablation Procedure
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
The ablation procedure was performed under
local anesthesia and conscious sedation. Vascular
access was obtained using the modied Seldinger
sheath in the right common femoral vein and
advanced up to the right ventricle. A Pentaray
catheter (Biosense Webster, Johnson & Johnson)
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R. Le Bouar et al.
was introduced in a 9F 20cm vascular sheath and
was subsequently advanced via the right common
femoral vein to the RV.The CARTO® 3 electroanatomic mapping system (Biosense Webster,
Johnson & Johnson) was used to guide mapping
and ablation of the accessory pathway.
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®).
Baseline intervals were AH = 86 ms,
HV=15ms, and HV=50ms.
Programmed ventricular stimulation
(S1=600ms, S2=230ms, S4=240ms) induced
a sustained monomorphic ventricular tachycardia
with a cycle length of 250ms, with LBBB and
superior axis (Fig. 10.4), which was hemodynamically moderately tolerated (dyspnea, palpitations, a drop in systolic blood pressure from
130 mmHg to 95 mmHg). The VT was terminated by three ventricular extrastimuli.
At his moment, the diagnosis of arrhythmogenic cardiomyopathy was established on the
basis of the presence of two major diagnostic criteria, according to current guidelines [1]: RV
dyskinesia and a ratio of RV end-diastolic volume to BSA of >110mL/m2 evidenced by cardiac MRI and sustained monomorphic VT with
LBBB morphology and superior axis.
Question 2: Where is the origin of the VT
presented in Fig. 10.3
A. RVOT.
B. LVOT.
C. RV septum.
D. LV septum.
E. RV lateral wall.
Given the 12-lead aspect of the VT (LBBB
morphology superior axis and a precordial transition in V4, with an RS aspect of the QRS com-
Fig. 10.4 Wide QRS complex tachycardia with a cycle length of 250ms initiated during programmed ventricular
stimulation, with left bundle branch block morphology and superior axis, compatible with VT
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plex in V4 and unique R in V5, a QRS width of
160ms), the diagnosis of arrhythmogenic cardiomyopathy, an origin at the level of the RV lateral
wall, was suspected. Mapping RV was therefore
commenced basal and lateral wall of the RV.
An anatomical map of the RV was initially
created. This showed a dilated RV with a volume
of 170mL.Next, a bipolar voltage map of the RV
was created with the Pentaray catheter (> 3.000
points). This demonstrated the presence of several adjacent “patchy” low voltage areas (<
0.5mV) measuring 15cm2 at the level of the lateral and basal RV wall (Fig.10.5).
The unipolar voltage map (cutoff values of
3.5 mV—5.3 mV) showed the presence of a
wider area of low-voltage local electrograms at
the level of the basal and lateral RV wall, in the
peri-tricuspid region, with additional narrow
areas of low-voltage electrograms at the level of
the anterior RVOT (Fig.10.6).
Next, an activation map of the RV during sinus
rhythm was created. This showed the presence of
a late activation region at the level of the basal
and lateral wall of the RV, corresponding to the
area of low-amplitude electrograms present on
the unipolar and on the bipolar voltage maps
(Fig.10.7).
Next, programmed ventricular stimulation
was performed with induction of the sustained
monomorphic VT from Fig. 10.4. However, an
activation map could not be performed, due to the
hemodynamically less well-tolerated character of
the tachycardia (near syncope, accompanied by a
drop in the systolic blood pressure from
110 mmHg to 75 mmHg). The VT was terminated with three ventricular extrastimuli.
Question 3: What would be the next best
step at this point of the procedure?
A. Terminate the procedure and prescribe
anti-arrhythmic drugs: amiodarone +
beta blockers.
B. Terminate the procedure and prescribe
anti-arrhythmic drugs: ecainide +
beta blockers.
C. Perform ablation in the area of late
activation during sinus rhythm, at the
level of the lateral LV wall.
D. Create a pacemap during sinus rhythm
to identify the VT circuit.
E. I don’t know.
Fig. 10.5 CARTO
image of the right
ventricle in RAO 45°,
showing the bipolar
voltage map, with an
area of low voltage
(<1.5mV) situated near
the tricuspid valve
toward the lateral wall of
the RV (encircled red
area)
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R. Le Bouar et al.
Fig. 10.6 CARTO image of the right ventricle in RAO
45° (same view as in Fig.10.5) showing the unipolar voltage map (low cutoff value = 3.5 mV, high cutoff
value=5.3mV), with an area of low voltage (<1.5mV)
situated near the tricuspid valve toward the lateral wall of
the RV (encircled red area), corresponding to the area of
Terminating the procedure and prescribing
anti- arrhythmic drugs were not a desired option,
neither by the performing physician nor the
patient. Identifying the VT circuit by creating a
pacemap during sinus rhythm was the option of
choice.
This was created by pacing from the distal
electrode of the roving/ablation catheter at a xed
coupling interval of 600ms in several areas of the
RV, with emphasis on the area of slow conduction
during sinus rhythm, based on the technique
described by de Chillou etal. [2, 3]. 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. A
superposed correlation of 95% was observed at
the level of the area corresponding to the exit
low voltage recorded by the bipolar voltage map. The
orange circle represents a small adjacent area of fragmented signals, partially superposed to the encircled area
of low voltage EGMs, where late potentials could be
recorded in sinus rhythm (Fig.10.7)
zone during VT and to the slow conduction area
during sinus rhythm, conrming the exit zone of
the VT.Pacemaping was continued in areas adjacent to the exit zone of the VT, until a site with a
very low correlation between the locally induced
morphology and the morphology of the VT was
found, corresponding to the entrance zone of the
VT.Between the entrance and the exit zone of the
VT, the VT isthmus was delineated. This was parallel to the tricuspid valve, with the entrance zone
being situated at the junction of the lateral, basal,
and inferior RV wall and the exit zone being situated toward the lateral and anterior RV wall. The
two outer loops of the VT were represented
between the exit and the entrance zones
(Fig.10.8). The mechanism was macro-reentry,
with a dual loop or “gure of 8” circuit.
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Fig. 10.7 CARTO image in RAO 25° showing the activation map of the right ventricle in sinus rhythm. In the encircled
orange area, a late local activation wavefront could be recorded (red arrow)
RF ablation was performed during sinus
rhythm, with a target power of 35W and a target
ablation index of 450. Several RF applications
were performed at the level of the VT isthmus.
The bipolar voltage map of the RV with superposed RF ablation lesions at the end of the abla-
Given the diagnosis of arrhythmogenic cardiomyopathy, a dual-chamber ICD was implanted
during hospitalization (Fig.10.11).
The patient was discharged from the hospital
48 h after ICD implantation on beta blocker
therapy.
tion is shown in Fig.10.9.
Programmed ventricular stimulation of up to
three extrastimuli, at two coupling intervals
(600 ms et 400 ms), with the shortest coupling
interval limited at 200ms, at two sites (apex of
the RV and RVOT), at baseline and after isoprenaline administration did not induce any sustained
arrhythmias.
There were no complications related to the
procedure.
Answers
Question 1: A.Sustained monomorphic
ventricular tachycardia.
Question 2: E.RW lateral wall.
Question 3: D.Create a pacemap during sinus rhythm to identify the VT
circuit.
The ECG post-ablation is shown in Fig.10.10.
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R. Le Bouar et al.
Fig. 10.8 CARTO image of the right ventricle in RAO
45° caudal 15° showing the pacemap, with the roving/
ablation catheter positioned at the level of the late activation zone in sinus rhythm (orange circle), where pacing
(yellow star) reproduces a QRS morphology with a concordance of 95% with the morphology of the clinical VT,
corresponding to the exit zone of the VT.The violet zone
corresponds to the entrance zone of the VT, where local
pacemap produced a discordant QRS morphology com-
pared to that of the clinical VT. The red curved arrows
indicate the direction of the propagation of the activation
wavefront during VT from the exit zone, corresponding to
the two outer loops of the VT (arrows added for learning
purpose). The straight red arrow indicates the direction of
the wavefront propagation inside the VT isthmus. The two
white lines represent the boundaries of the VT isthmus
(added for learning purpose)
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Fig. 10.9 CARTO image of the right ventricle in RAO
45° showing the bipolar voltage map post-RF ablation at
the level of the VT isthmus (white lines) and exit zone
(orange circle). The pink and red dots represent RF lesions
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Fig. 10.11 Chest X-ray performed after the ICD implantation showing the distal end of the ventricular electrode
situated at the level of the RV apex and the distal end of
the atrial electrode at the level of the right atrial
appendage
Fig. 10.10 A 12-lead ECG recorded after the ablation procedure, showing sinus rhythm with a heart rate of 62bpm,
QRS axis at +55°, and incomplete RBBB
Commentary
The present case illustrates a catheter ablation
procedure of a sustained monomorphic ventricular tachycardia in a 59-year-old male patient with
newly diagnosed arrhythmogenic cardiomyopathy. Several observations can be made about the
present case.
Arrhythmogenic cardiomyopathy, formerly
known as arrhythmogenic right ventricular dysplasia/arrhythmogenic right ventricular cardiomyopathy, is a heritable cardiac genetic disease
characterized by bro-fatty replacement of ventricular myocytes. Its prevalence is estimated to
be around 1 in 5,000 individuals [4]. It affects
both ventricles, with a right ventricular
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R. Le Bouar et al.
predominance [5]. The disease is caused by
mutations in genes encoding desmosomal proteins: plakoglobin (JUP), plakophilin-2 (PKP2),
desmoglein-2 (DSG2), desmoplakin (DSP), desmocollin-2 (DSC2), transforming growth factor
beta-3 (TGF3), and transmembrane protein family members (TMEM) [1]. It is mainly transmitted in an autosomal dominant fashion, but
autosomal recessive transmitted forms exist, in
syndromes associating arrhythmogenic cardiomyopathy and cutaneous modications, such as
the Naxos syndrome and the Carvajal syndrome.
The primary manifestations of arrhythmogenic cardiomyopathy are mainly ventricular
arrhythmias, followed by right heart failure. It is
one of the primary causes of sudden cardiac death
in young adults, accounting for 11% of causes
and 22% of cases in competitive athletes [4].
Establishing the correct diagnosis relies on a set
of criteria showing the presence and the consequences of the bro-fatty replacement of the ventricular myocytes [1]. The differential diagnosis
takes into account RVOT VT in patients with
structurally normal heart, Uhl’s anomaly, dilated
cardiomyopathy, sarcoidosis, myocarditis, and
Brugada syndrome. Treatment addresses mainly
ventricular arrhythmias and heart failure. For
ventricular arrhythmias, anti-arrhythmic drugs,
catheter ablation, and ICD implantation are possible options.
Ventricular arrhythmias in patients with
arrhythmogenic cardiomyopathy originate
mainly in the right ventricle, but they can arise
from the LV also, when there is biventricular
involvement. The most common sites involved in
the right ventricle include the RVOT, the RV
apex, and the lateral RV wall. Several morphologies of VT have been described. In the study of
Marcus etal. [6], the most common morphology
was LBBB with superior axis (36.8%), followed
by LBBB inferior axis (26.3%), LBBB indeterminate axis (21%), indeterminate morphology
(13%), and RBBB pattern in 2.6%.
The differential diagnosis of VT arising from
the right ventricle is most often made with RVOT
VT in patients with no structural heart disease.
Both the 12-lead ECG recorded during VT and
during sinus rhythm can provide useful clues
regarding one etiology or the other. The ECG
recorded during sinus rhythm may show T wave
inversion in the right precordial leads (V1 to V3)
in 32% of patients with arrhythmogenic cardiomyopathy. They can be found in only 1–3% in
healthy young individuals and in up to 4% of
patients with RVOT VT in the absence of arrhythmogenic cardiomyopathy [7–10]. However,
according to Kazmierczak etal. (1998), negative
T waves in the anterior leads can be found in 50%
of patients with arrhythmogenic cardiomyopathy,
as well as in 20% of patients with TV from RVOT
and no structural heart disease.
The cornerstone of sustained VT/VF treatment in patients with arrhythmogenic cardiomyopathy is ICD implantation. As shown before,
this reduces mortality and improves prognosis in
this population of patients [11, 12]. However, frequent ICD shocks are associated with an impaired
quality of life. Catheter ablation of ventricular
arrhythmias has been associated with a reduction
in the number of ICD shocks and has successfully been performed in patients with arrhythmogenic cardiomyopathy. Besides reducing the
number of ICD discharges, catheter ablation has
been shown to have other potential benets. In
their study, Mathew etal. [13] also found a trend
toward an improved outcome (freedom from sustained VT/VF, heart transplant, and death,
p=0.058) in their population of 47 patients, after
a mean 1.7 ablation procedures, with 56% of procedures requiring an endocardial-only approach,
13% an epicardial-only approach, and 31% a
combined endo-epi approach. Freedom from sustained VT/VF was 63% at 1 year and 45% at
5 years after multiple procedures, with 36% of
patients requiring an endocardial-only approach.
Therefore, according to this study, almost twothirds of patients require an epicardial approach
or a combined endo-epi approach for a successful
VT ablation.
In the above-presented patient, only one VT
morphology was present, as demonstrated by
the PVS at the beginning of the EP study. The
endocardial- only approach was enough to
achieve successful VT ablation. The bipolar
voltage map was able to identify areas of lowamplitude electrograms, corresponding to path-
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ological myocardial tissue, most likely brosis.
As in other types of cardiomyopathies, in
patients with arrhythmogenic cardiomyopathy,
brosis represents the substrate of ventricular
tachycardia [14]. The activation map recorded
during sinus rhythm identied a zone of late
ventricular activation (Fig. 10.7, Video 10.1),
which corresponded to the zone of slow conduction identied by the bipolar voltage map
(Fig.10.5) and which turned out to be the VT
isthmus identied by the pacemap during sinus
rhythm (Fig.10.8). Of note, the unipolar voltage
map suggested the presence of an epicardial
scar, as shown by the areas of low voltage. As
demonstrated by Scanavacca etal. [15] in their
study on patients with Chagas myocarditis, low
endocardial unipolar voltage was an independent predictor of epicardial bipolar scar, with a
71% sensitivity and 75% specicity when using
a cutoff value of 4.0mV.Hutchinson etal. [16]
proposed a cutoff value of 8.3mV for unipolar
voltage maps as a good identier of epicardial
scar in patients with VT and nonischemic cardiomyopathy. Weintraub et al. suggest cutoff
values of 3.5–5.5mV for endocardial unipolar
voltage maps [17] and Venlet etal. of 3.7mV or
3.9mV [18].
In this patient, RF ablation at the level of the
VT isthmus rendered the VT non-inducible. An
ICD was subsequently implanted despite the
good result of the ablation procedure, according
to the current recommendations and given the
progressive character of the disease, for the secondary prevention of sudden cardiac death [19].
Learning Points
• Syncope can be the rst manifestation in
patients with arrhythmogenic
cardiomyopathy.
• This can be due to fast sustained mono-
morphic ventricular tachycardia.
• The electrophysiological study can
establish the presence of malignant ventricular arrhythmias when noninvasive
workup raises suspicion about the possible arrhythmic nature of syncope.
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• The diagnosis of arrhythmogenic cardiomyopathy requires a set of criteria
demonstrating the presence and consequences of the bro-fatty replacement
of ventricular myocardium.
• Catheter ablation of ventricular tachycardia in the setting of arrhythmogenic
cardiomyopathy is a good treatment
option, since all anti-arrhythmic drugs
are palliative.
• ICD implantation is indicated in such
patients despite successful catheter
ablation, given the progressive character
of the disease and the risk of sudden cardiac death.
References
1. Marcus FI, McKenna WJ, Sherrill D, Basso C, Bauce
B, Bluemke DA, etal. Diagnosis of arrhythmogenic
right ventricular cardiomyopathy/dysplasia: proposed
modication of the task force criteria. Circulation.
2010;121(13):1533–41.
2. de Chillou C, Groben L, Magnin-Poull I, Andronache
M, MagdiAbbas M, Zhang N, et al. Localizing the
critical isthmus of postinfarct ventricular tachycardia:
the value of pace-mapping during sinus rhythm. Heart
Rhythm. 2014;11(2):175–81.
3. de Chillou C, Sellal JM, Magnin-Poull I.Pace mapping
to localize the critical isthmus of ventricular tachycardia. Card Electrophysiol Clin. 2017;9(1):71–80.
4. Gemayel C, Pelliccia A, Thompson
PD. Arrhythmogenic right ventricular cardiomyopathy. J Am Coll Cardiol. 2001;38(7):1773–81.
5. Corrado D, Link MS, Calkins H. Arrhythmogenic
right ventricular cardiomyopathy. N Engl J Med.
2017;376(1):61–72.
6. Marcus FI, Zareba W, Calkins H, Towbin JA, Basso
C, Bluemke DA, et al. Arrhythmogenic right ventricular cardiomyopathy/dysplasia clinical presentation and diagnostic evaluation: results from the North
American multidisciplinary study. Heart Rhythm.
2009;6(7):984–92.
7. Marcus FI, Zareba W.The electrocardiogram in right
ventricular cardiomyopathy/dysplasia. How can the
electrocardiogram assist in understanding the pathologic and functional changes of the heart in this disease? J Electrocardiol. 2009;42(2):136.e1–5.
8. Marcus FI. Prevalence of T-wave inversion beyond
V1 in young normal individuals and usefulness
for the diagnosis of arrhythmogenic right ven-
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