CẬP NHẬT

HƯỚNG DẪN CẮT ĐỐT QUA
CATHETER CÁC RỐI LOẠN NHỊP
Ở TRẺ EM
BS Bùi Thế Dũng
BV Đại học Y Dược – TP. HCM


TÀI LIỆU THAM KHẢO
1. Freidman RA (2002), "NASPE Expert Consensus
Conference: Radiofrequency Catheter Ablation in
Children with and without Congenital Heart
Disease“
2. Cohen MI (2012), "PACES/HRS Expert Consensus
Statement on Asymptomatic Young Patient With
WPW Pattern"
3. Saul JP (2016), "PACES/HRS expert consensus
statement on the use of catheter ablation in children
and patients with congenital heart disease“


3 main issues
1.
2.
•
•
•
•
•
•

3.

Safety - Efficacy
Procedure:
laboratory equipment
personnel
ablation energy
catheter choice
sedation/anesthesia
pre- and post-ablation procedure management
Arrhythmia type


SAFETY - EFFICACY
 The 2002 consensus: depended on patient age,
typically expressed as “< or > 5 years”
 HRS 2014: 2 groups: ≤ 12 years or 12 – 18
years
 The 2016 consensus: patient weight was more
important than age – chose cutoff “15 kg”
 Succes rate of RFCA:
1991 – 1995 (Early Era, n=4193): 90.4%
1996 – 1999 (Late Era, n=3407): 95.2%


SAFETY - EFFICACY
 2000 – 2002 (n=2761, 41 centers):
Succes rate of RFCA: 93% SVT, 78% VT
Recurrence at 12 months: 24.6% right septal
APs, 15.8% right freewall APs; 9.3% left free

wall APs, 4.8% left septal APs; 4.8% AVNRT
 Complications:
1991 – 1995: 4.2%
1996 – 1999: 3%


Complications
 Death and major complications:
 congenital heart disease
 lower patient weight
 greater number of RF applications
 left-sided procedures
 Three most common serious complications:
 AV block: 0.89 – 0.56%
 Perforation or pericardial effusion: 0.69 – 0.53%
 thrombi or emboli: 0.37 – 0.19%


Fluoroscopy Exposure
Deterministic effects
(threshold level is 2 Gy)

Stochastic effects
(dose independent)

Skin erythema

Malignancies: 0.02% – 0.03%

Epilation


Hereditary defects

Cataracts
Retarded bone growth
Sterility

Decreased white blood cell
Organ atrophy
Fibrosis


Techniques to Reduce
Procedure-Based Radiation
1. As Low as Reasonably Achievable (ALARA)
• Pulsed fluoroscopy
• Lower frame rate
• Adjusting collimators to decrease field view
• Limiting the use of magnification
• “store fluoro” function instead of cineangiography
• Alternating between two views rather than a single
imaging view to minimize site exposure
2. Nonfluoroscopic systems
• 3-D imaging systems + TEE or ICE


Anesthesia and Sedation
 Aims: improve patient comfort, reduce movement, and
have minimal effect on the arrhythmia substrate
 Personnel:

• Pts > 12 years: nurse anesthetist
• Pts ≤ 12 years: nurse anesthetist + anesthesiologist
 General anesthesia with endotracheal intubation or
laryngeal mask: age ≤ 12 years, significant CHD;
ventricular dysfunction; pulmonary hypertension;
hemodynamic instability; prolonged procedure; the need
for complete immobility and patient or parent choice.


Safety Recommendations
Class I
 In-house pediatric cardiovascular surgical support for
patients < 15 kg
 A pediatric (or congenital) cardiovascular surgical
program at the same institution where the ablation is
performed for patients ≤ 12 years of ages
 Age-appropriate cardiovascular surgical program and
back-up at the same institution where the ablation is
performed for patients from 12 to 18 years of ages


Safety Recommendations
Class I
 For patients ≤ 12 years of and/or with moderate or
complex CHD, the procedure staff should have a
pediatric and/or CHD pts anesthesiologist
 Fluoroscopy use should be as low as possible
 Anticoagulation with unfractionated heparin: When
the procedure will take place in the left atrium or
ventricle, or there is a known or potential right-to-left

shunt to prevent systemic embolization (ACT: 250 –
300 s during procedures)


Safety Recommendations
Class IIa
Cryoablation is useful for septal substrates and
proximity to smaller coronary arteries
Class IIb
Cryoablation can be useful for pts < 15 kg
Class III
Ablation is not recommended for patients with
an intracardiac thrombus


Procedural Recommendations
Class I
 EP lab and postprocedure recovery unit should be
suitable for the care of pediatric and CHD pts
 Ablation for patients with moderate or complex CHD
or complex arrhythmias should be performed by an
electrophysiologist with the appropriate expertise
 3D mapping system should be available and strongly
considered for mapping and ablation of postoperative
arrhythmias in patients with moderate or complex CHD


Procedural Recommendations
Class IIa
Irrigated or large electrode-tip RF catheters

can be useful for the ablation of postoperative
arrhythmias in patients with CHD
Nonfluoroscopic imaging can be useful to
reduce radiation exposure
Cryoablation can be useful for slow pathway
modification in pediatric patients with AVNRT


Clinical Presentations
1.
•
•
•
•
2.
3.

SVT
AVNRT
AVRT
AT
AFL
WPW pattern and AP mediated Tachycardias
VT


Indications for SVT Ablation
Class I
 Documented SVT, recurrent or persistent associated
with ventricular dysfunction in pts > 15 kg

 Documented SVT, recurrent or persistent when
medical therapy is either not effective or is intolerant
 Documented SVT, recurrent or persistent when the
family wishes to avoid chronic drugs in pts > 15 kg
 Recurrent hemodynamic compromise (hypotension or
syncope) from SVT in pts > 15 kg
 Recurrent SVT requiring emergency medical care or
electrical cardioversion for termination in pts > 15 kg


Indications for SVT Ablation
Class II a
Recurrent symptoms clearly consistent with
PSVT in pts > 15 kg, and one of the following:
evidence of AP involvement; inducible SVT
Slow pathway modification in pts > 15 kg with
documented SVT, when SVT is not inducible
at EP testing, but evidence for dual AV nodal
physiology. Cryotherapy should be considered


Indications for SVT Ablation
Class II b
Recurrent symptoms clearly consistent with
PSVT in pts < 15 kg, and one of the following:
evidence of AP; inducible SVT.
Cryotherapy should be considered
Recurrent hypotension or syncope from SVT
in pts < 15 kg
Intermittent symptomatic SVT which is

nonsustained (less than 30s) in pts > 15kg


Indications for SVT Ablation
Class III
SVT controlled with medical therapy without
intolerable adverse effects in pts < 15 kg
Clinical symptoms consistent with SVT, but no
inducible SVT, and no evidence for dual AV
nodal physiology during EP testing
Slow pathway modification when dual AV
node physiology is demonstrated after ablation
of a different arrhythmia substrate (such as an
AP when there is no inducible AVNRT


Indications for WPW pattern Ablation
Class I
WPW pattern following cardiac arrest
WPW pattern with syncope when there are
predictors of high risk for cardiac arrest (The
shortest preexcited RR interval during AF, or
during incremental atrial pacing ≤ 250 ms;
Multiple accessory pathways)


Indications for WPW pattern Ablation
Class II a
 WPW pattern with ventricular dysfunction in pts
> 15 kg, or when medical therapy is either not

effective or intolerant in pts < 15 kg
 WPW pattern with predictors of high risk for
cardiac arrest in pts > 15 kg
 WPW pattern with syncope, without predictors of
high risk for cardiac arrest in pts > 15 kg
 Asymtomatic WPW pattern in pts > 15 kg when
the absence of WPW pattern is a prerequisite for
participation in personal or professional activities


Indications for WPW pattern Ablation
Class II b
Asymtomatic WPW pattern in pts > 15 kg
without high risk for cardiac arrest because of
a patient or family choice
Class III
WPW pattern caused by a fasciculoventricular
accessory pathway
WPW pattern without symptoms in pts < 15 kg


Indications for ablation of
ventricular arrhythmias without CHD
Class I
 VPCs or VT caused ventricular dysfunction, when
medical therapy is either not effective or intolerant, or
as an alternative to medical therapy in pts > 15 kg
 Recurrent or persistent symptomatic verapamil –
sensitive VT, idiopathic outflow tract VT, or VT with
hemodynamic compromise, when medical therapy is

either not effective or intolerant, or as an alternative
to medical therapy in pts > 15 kg (LOVT-VT was a
Class IIa indication in the prior pediatric guidelines)


Indications for ablation of
ventricular arrhythmias without CHD
Class II a
 VPCs with correlated symptoms in pts > 15 kg
Class II b
 Accelerated
idioventricular
rhythm
with
correlated symptoms in pts > 15 kg
(Class IIa in the prior pediatric guidelines)
 Recurrent/frequent
polymorphic
ventricular
arrhythmia when there is a suspected triggering
focus, arrhythmia, or substrate that can be
targeted


Indications for ablation of
ventricular arrhythmias without CHD
Class III
VT in pts < 15 kg controlled medically, or is
well tolerated without ventricular dysfunction
Acc. idioventricular rhythm in pts < 15kg

Asymptomatic VPCs, VT, or accelerated
idioventricular rhythm that is not suspected of
causing or leading to ventricular dysfunction
VPCs, VT due to transient reversible causes