Pulmonary valve replacement in tetralogy of Fallot improves the repolarization.
OBJECTIVE
To assess the effect of pulmonary valve replacement (PVR) on the repolarization of patients with tetralogy of Fallot.


BACKGROUND
Pulmonary valve regurgitation may cause right ventricular failure in adult patients with Fallot's tetralogy. In these patients, prolonged depolarization and disturbed repolarization are associated with ventricular arrhythmias and sudden cardiac death.


METHODS
Thirty Fallot patients (age 32+/-9 years, 19 male) eligible for PVR were studied with cardiac magnetic resonance imaging (CMR) before and 6 months after PVR. Electrocardiograms obtained during initial and follow-up CMR were analyzed and occurrence of ventricular arrhythmias was studied.


RESULTS
Right ventricular end-diastolic volume (RV EDV) decreased from 322+/-87 to 215+/-57 ml after PVR (P<0.0001). The spatial QRS-T angle normalized from 117+/-34 to 100+/-35 degrees , P=0.0004 (normal angle <105 degrees). QT dispersion and T-wave complexity did not change significantly. T-wave amplitude decreased from 376+/-121 to 329+/-100 microV (P=0.01). T-wave area decreased from 43+/-15 to 38+/-13 microV s (P=0.02). Decreases in T-wave amplitude and area were most prominent in the right precordial leads overlying the RV. Three patients had sustained ventricular arrhythmias and one patient died suddenly. These patients had a QRS duration >160 ms. No severe ventricular arrhythmias were found in patients with a RV EDV <220 ml, QRS-T angle <100 degrees , QT dispersion <60 ms or T-wave complexity <0.30.


CONCLUSIONS
Normal repolarization indices may be associated with the absence of severe ventricular arrhythmias. PVR in Fallot patients with dilated right ventricles has a beneficial effect on electrocardiographic indices of repolarization heterogeneity.
Hooft van Huysduynen
Bart
B
Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, PO Box 9600, 2300 RC Leiden, The Netherlands.
Henkens
Ivo R
IR
Swenne
Cees A
CA
Oosterhof
Thomas
T
Draisma
Harmen H M
HH
Maan
Arie C
AC
Hazekamp
Mark G
MG
de Roos
Albert
A
Schalij
Martin J
MJ
van der Wall
Ernst E
EE
Vliegen
Hubert W
HW
D000328:Adult; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D019918:Heart Valve Prosthesis Implantation / Q000379:methods*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D011664:Pulmonary Valve / Q000601:surgery*; D011665:Pulmonary Valve Insufficiency / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery; D017180:Tachycardia, Ventricular / Q000517:prevention & control; D013771:Tetralogy of Fallot / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D016896:Treatment Outcome