Hướng dẫn cắt đốt qua Catheter các rối loạn nhịp ở trẻ em - Bùi Thế Dũng

.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. SVT 
• AVNRT 
• AVRT 
• AT 
• AFL 
2. WPW pattern and AP mediated Tachycardias 
3. 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 
Indications for ablations 
in patients with CHD 
Class I 
Recurrent or persistent AT, SVT related to AP or 
twin AV nodes in patients with CHD when 
medical therapy is either not effective or 
intolerant. Ablation is also recommended as an 
alternative to medical therapy for pts > 15 kg 
WPW pattern and high-risk, commonly in 
Ebstein’s anomaly, in pts > 15 kg 
Ablation as adjunctive therapy to an ICD in pts 
with recurrent monomorphic VT, a VT storm, or 
multiple appropriate shocks that are not 
manageable by device reprogramming or drug 
Indications for ablations 
in patients with CHD 
Class II a 
• Sustained monomorphic VT causing symptoms 
or hypotension, when drug therapy is not 
effective or intolerant. Ablation is an alternative 
to medical therapy in pts > 15 kg 
• AVNRT when medical therapy is either not 
effective or intolerant in pts > 15 kg with 
moderate or complex CHD 
Class I Indications for Ablation for 
Infants and Patients <15 kg 
 Pediatric cardiovascular surgical support should be 
available in-house during ablation procedures 
Documented SVT, when medical therapy is either not 
effective or intolerant 
WPW pattern following resuscitated cardiac arrest 
WPW pattern with syncope when there are predictors 
of high risk for cardiac arrest 
 Idiopathic JET, or congenital JET associated with 
ventricular dysfunction, when medical therapy is either 
not effective or intolerant (cryotherapy is preferred) 
Class I Indications for Ablation for 
Infants and Patients <15 kg 
VPC or VT with ventricular dysfunction, when 
medical therapy is not effective or intolerant 
SVT related to accessory AV connections or twin 
AV nodes in patients with CHD when medical 
therapy is either not effective or intolerant 
Symptomatic AT occurring outside the early 
postoperative phase (less than 3 – 6 months) in 
patients with CHD, when medical therapy is 
either not effective or intolerant 
Summary 
The important roles of advancements in imaging 
technologies and ablation energy sources 
• nonfluoroscopic systems 
• higher-energy RF sources 
• cryoenergy 
Patient weight was more important than age 
High succes rate and safety if follow guideline