Study population
A 12-year-old girl weighing 46 kg and 165 cm in height (with a body
surface area of 1.45 m2) presented with almost
incessant, drug-refractory AT was referred for radiofrequency catheter
ablation. She had a 5-month history of palpitations, and the
electrocardiogram (ECG) showed persistent atrial tachycardia with
variable (3-1:1) conduction, and a maximum heart rate of 150 beats/min
(Figure 1).
The echocardiogram revealed enlarged left atrium diameter (LAD, 37 mm;
normal range < 35 mm). The left ventricular end-diastolic and
end-systolic diameters (LVEDD and LVESD) were 48 (normal range
< 48 mm) and 30 mm, respectively, with a normal left
ventricular ejection fraction (LVEF) of 67% (Table 1). The markers of
myocardial injury were normal, and no inflammatory edema of myocardial
tissue was found by echocardiography. The ECG was repeated, and the
results showed the AT was in the range of 140-180 beats/minute without
dynamic ST change. The atrial tachycardia lasted for more than 2 days
with elevated NT-proBNP (2586 pg/ml, normal range < 285
pg/ml), elevated GPT (109 U/L, normal range < 75 U/L), and
elevated GOT (43 U/L, normal range < 38 U/L) level.
After ruling out reversibility and other causes, the patient was
admitted to the hospital for electrophysiology examination and ablation.
Transesophageal echocardiography (TEE) was performed before ablation to
verify the absence of a left atrial thrombus and guide LAA resection.
Patients had been treated with anticoagulants before ablation.