[ECG changes after transcatheter correction of the secondary defect of the interatrial septum with Amplatzer...

To study ECG changes after transcatheter correction of the interatrial defect (IAD) with Amplatter occluder.

Secondary transcatheter IAD correction was made with Amplatzer Septal Occluder (AGA Medical Corporation, U.S.A.) in 33 adults (mean age 33.5 +/- 2.3 years) and 22 children (mean age 11.2 +/- 1.3 years). Short- and long-term outcomes of the defect correction were followed up for 1 to 12 months.

Ectopic atrial rhythm registered initially in 2 adult patients was corrected to 1 month after the operation. Normalization or reduction of the electric axis of the heart (EAH) deviation were achieved in 45.5% adults and 66.7% children who had vertical axis or right shift of the axis. Baseline right ventricular hypertrophy (RV, +SV(5,6) > 10.5 mm) was diagnosed in 10 adults and 9 children. To the end of the first year after IAD correction this hypertrophy was detected in 5 adults and 3 children (50 and 33.3%, respectively). Blockade of the right bundle of His (complete in 5 cases and incomplete in 23 cases) was diagnosed before treatment in 18 adults and 10 children. To month 12 after the defect correction incomplete blockade persisted only in 2 (11.1%) adults and 1 (10%) child. In 6 months P wave amplitude diminished in adults from 1.9 +/- 0.12 to 1.7 +/- 0.10 mm (p<0.01), in children--from 1.8 +/- 0.07 to 1.6 +/- 0.11 mm (p<0.05). QRS complex duration decreased both in adults and children (from 0.10 +/- 0.003 to 0.08 +/- 0.004 s, p<0.01 and from 0.09 +/- 0.003 to 0.08 +/- 0.002 s, p<0.05, respectively). In the latter duration of the interval P-Q reduced significantly in 3 months from 0.18 +/- 0.005 to 0.17 +/- 0.005 s (p<0.05).

ECG changes after transcatheter correction of IAD manifest with normalization of the EAH or reduction of its shift to the right, regress of right ventricular hypertrophy, elimination or reduction of the right bundle of His and absence of significant deterioration of cardiac arrhythmia.