[CRT-FORUM] 35E 4 years old girl, with a Dilated Cardiomiopathy. Dr. De Boeck

[CRT-INFO]

Dear colleague de la Paz from Cuba,
There is emerging evidence that -in particular in a pediatric 
population, WPW can induce dyssynchrony and heart failure (see 
references). This is particularly the case for septal bypasses, in which 
the physiology resembles that of a common left bundle branch block 
(LBBB). In such cases, dyssynchrony is often visible by the naked eye as 
septal bouncing or apical rocking, often there is septal thinning. 
However, one should realize that there is a major difference with LBBB 
in that there is no delayed contraction in WPW, only premature 
contraction. The LV free wall is not only timely activated compared to 
the atrial filling but moreover also via the normal His-Purkinje system. 
Such activation ensures a normal endo-to epicardial activation and 
better preservation of systolic/diastolic performance. The most 
physiologic reynchronization that you can achieve will therefore be to 
take away the cause of the premature activation, this is a 
radiofrequency ablation (RFCA) of the accessory pathway in WPW. At least 
two pediatric reports in recent literature show that RFCA restores 
normal synchrony and improves LV function in children with septal 
bypasses and EF< 50%. The only real safety concern of an ablation would 
be accidental ablation of the AV-node/His bundle itself, Only in that 
case a biventricular device would be needed. In other cases, 
"resynchronization" by a device would result in an unneccessary early 
contraction of the lateral wall (unfavorable diastolic filling) and an 
unphysiological epicardial to endocardial contraction sequence. Also, 
devices in children are problematic for a number of other reasons, as 
children (but not hteir devices/leads) are growing, face a lot of 
device/battery changes in their life and an increased risk for 
complications. If there is really evidence for severe sinus node 
dysfunction during electrophysiologic study or after RFCA, an atrial 
lead pacing-system is still possible.

Best regards,

Bart De Boeck,
UMCUtrecht, the Netherlands & USBasel, Switzerland

1/ Emmel M, Balaji S, Sreeram N: Ventricular preexcitation associated 
with dilated cardiomyopathy: a causal relationship? Cardiol Young 2004, 
14:594-599.
2/ Tomaske M, Janousek J, Razek V, Gebauer RA, Tomek V, Hindricks G, 
Knirsch W, Bauersfeld U: Adverse effects of Wolff-Parkinson-White 
syndrome with right septal or posteroseptal accessory pathways on 
cardiac function. Europace 2008, 10:181-189.
> COLLEAGUES OF THE CRT SYMPOSIUM : My name is Pedro de la Paz, a 
> pediatric cardiologist of Matanzas, Cuba. I would ask you about a 4 
> years old girl, with a Dilated Cardiomiopathy, symptomatic (class 
> II-III NYHA) with severe depressed LVEF, less than 30%, under 
> treatment with furosemide, spironolactone, captopril and carvedilol,  
> a WPW syndrome and a simple sinusal arrhythmia (probable sinus node 
> dysfunction),  is it possible to consider the electrical device 
> implantation (PM), to improve her VI disfunction ?
>
> thanks Dr Pedro (Cuba)
>


-- 
Dr. Sergio Dubner
President of Scientific Committee

Dr. Edgardo Schapachnik
President of Steering Committee