Benito Musto, Berardo Sarubbi*, Valentino Ducceschi*, Antonio D’Onofrio, Ciro Cavallaro, Filippo Vecchione, Carmine Musto, Raffaele Calabro*.
*Division of Paediatric Cardiology, Second University of Naples, Monaldi Hospital, Division of Cardiology, Monaldi Hospital, Naples, Italy
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BACKGROUND. Congenital junctional ectopic
tachycardia (JET) is a rare supraventricular tachycardia, presenting in the first six months of life
as persistent sustained form, associated in up to 60% of cases with cardiomegaly and heart
failure. The purpose of our study is to examine retrospectively the clinical presentation and
outcome of a cohort of 9 patients with congenital JET referred during a 20-year period time to a
single Unit and all medically treated.
METHODS. Nine patients (2 M and 7 F, mean age 3.9 months) suffering from persistent
sustained JET were referred to Monaldi Hospital between 1980 and 1999. All the patients
underwent medical treatment.
Digoxin was given in controlling the symptoms of cardiac failure, in presence of cardiomegaly
and/or decreased LV ejection fraction. Propafenone was used in all the patients, alone or in
combination with digoxin, as first step of treatment. Amiodarone was administered when
propafenone resulted ineffective after 4 days of treatment. A Ic antiarrhythmic drug (propafenone
or flecainide) was associated to amiodarone when it resulted ineffective, alone, in controlling the
arrhythmia. Treatment success was defined as a stable decrease in the ventricular rate £140
beats/min; while partial success was defined as a decrease in the rate of tachycardia (usually heart
rate £170 bpm) which resulted in alleviation of symptoms.
RESULTS. At presentation the age of patients varied from 1 to 6 months and the
ventricular rate ranged between 170 and 300 bpm. A family history of JET was positive in 55.6%
of the patients (5/9). Four patients (44.4%) exhibited clinical signs of heart failure and 6/9
(66.7%) echocardiographic evidences of impaired LV function. In 3 patients propafenone, used alone,
resulted in a partial success. In the other 6 patients the drug was completely ineffective. In these
patients irresponsive to propafenone, amiodarone resulted in 2 total successes, 1 partial success
and 3 failures. The combination of amiodarone + propafenone resulted in 2 total successes and 1
partial success. Systemic side effects did not occur during pharmacological treatment in all the
patients, nor deterioration of ventricular function during drug-treatment. No-one of the patients
underwent catheter ablation to control the arrhythmia.
CONCLUSION. JET therapy relay on different medical option; surgical or radiofrequency
ablation are extreme procedures that might be required in drug-refractory JET, especially in adults
or in patients with severe congestive failure not responsive to medical management. Physicians
should not be discouraged by initial failure, because “true” drug-refractory JET are very rare. In
those cases not responding to a single drug regimen, an association of antiarrhythmic agents
having different electrophysiological effects, may control otherwise untreatable JET.
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