Prevalence of Wolff-Parkinson-White syndrome, association with congenital heart disease, and natural history in newborns
Presented By:
Maria Munk Pærregaard1, Joachim Haartmann1, Christian Pihl1, Adrian Pietersen1, Kasper Karmark Iversen1, Henning Bundgaard2, Alex Hørby Christensen1,2*
1) Department of Cardiology, Herlev-Gentofte Hospital, Copenhagen University Hospital, Copenhagen, Denmark. 2) Department of Cardiology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.
maria.munk.paerregaard@regionh.dkOverview:
Background: Wolff-Parkinson-White (WPW) syndrome is characterized by an accessory electrical pathway between the atria and ventricles. Clinically, the condition can lead to supraventricular tachycardia, and is associated with sudden cardiac death and congenital heart disease. Studies inves-tigating the prevalence, associated structural cardiac abnormalities, and natural history in newborns are few.
Purpose: To determine the prevalence of WPW syndrome in newborns, describe electrocardio-graphic and echocardiographic characteristics, and the natural history in childhood.
Methods: Electrocardiograms (ECGs) and echocardiograms of newborns (aged 0-30 days) from a large, prospective, general population study were included. WPW cases were identified through manual evaluation of outliers in PR-interval, QRS-duration, and QRS axis. Newborns with suspect-ed or confirmed pre-excitation on their initial ECG were offered a cardiac follow-up. Localization of the accessory pathway was assessed utilizing a QRS polarity algorithm. Cases were matched 1:4 to controls by age, sex, weight and gestational age.
Results: Among the 17,489 ECGs we identified 17 (76% boys) newborns with definite WPW syn-drome consistent with a prevalence of 0.1%. At follow-up (available in 12/17 children) at a mean age of three years, the WPW pattern remained in three children while the ECG had normalized in the nine remaining children. The median values for the newborns’ heart rate, PR-interval, QRS-duration, QTc(Bazett), the maximum amplitude in R-V1 and S-V6 in cases and controls were 131 vs. 142 beats per minute, 80 vs. 96 ms, 74 vs. 56 ms, 449 vs. 420 ms, 1,562 vs. 1,028 µV and 546 vs. 693 µV, respectively (all p<0.05, Figure 1). The newborns’ QRS axis, max amplitude in S-V1 and R-V6 did not differ among cases and controls (all p>0.05). Echocardiographic measurements of the newborns’ left ventricular diameter and function, wall thicknesses, and doppler measurements of trans-mitral- and main pulmonary artery blood flow did not differ significantly between cases and controls (all p>0.05). The accessory electrical pathway was left-sided in 14 (82%) of the new-borns. One newborn had significant mitral regurgitation while all other newborns had structurally normal hearts; there were no cases of Ebstein’s anomaly.
Conclusion: The prevalence of WPW syndrome in our cohort of asymptomatic newborns was 0.1%. The syndrome was more frequent in boys, the accessory pathway was mostly left-sided, and was associated with changes in several ECG parameters, but generally not associated with structural heart disease. A striking observation was, that the WPW pattern in the majority of children could not be reproduced on follow-up ECGs at a mean age of three years, suggesting either that the ECG pattern is intermittent, or normalization occurs.
Purpose: To determine the prevalence of WPW syndrome in newborns, describe electrocardio-graphic and echocardiographic characteristics, and the natural history in childhood.
Methods: Electrocardiograms (ECGs) and echocardiograms of newborns (aged 0-30 days) from a large, prospective, general population study were included. WPW cases were identified through manual evaluation of outliers in PR-interval, QRS-duration, and QRS axis. Newborns with suspect-ed or confirmed pre-excitation on their initial ECG were offered a cardiac follow-up. Localization of the accessory pathway was assessed utilizing a QRS polarity algorithm. Cases were matched 1:4 to controls by age, sex, weight and gestational age.
Results: Among the 17,489 ECGs we identified 17 (76% boys) newborns with definite WPW syn-drome consistent with a prevalence of 0.1%. At follow-up (available in 12/17 children) at a mean age of three years, the WPW pattern remained in three children while the ECG had normalized in the nine remaining children. The median values for the newborns’ heart rate, PR-interval, QRS-duration, QTc(Bazett), the maximum amplitude in R-V1 and S-V6 in cases and controls were 131 vs. 142 beats per minute, 80 vs. 96 ms, 74 vs. 56 ms, 449 vs. 420 ms, 1,562 vs. 1,028 µV and 546 vs. 693 µV, respectively (all p<0.05, Figure 1). The newborns’ QRS axis, max amplitude in S-V1 and R-V6 did not differ among cases and controls (all p>0.05). Echocardiographic measurements of the newborns’ left ventricular diameter and function, wall thicknesses, and doppler measurements of trans-mitral- and main pulmonary artery blood flow did not differ significantly between cases and controls (all p>0.05). The accessory electrical pathway was left-sided in 14 (82%) of the new-borns. One newborn had significant mitral regurgitation while all other newborns had structurally normal hearts; there were no cases of Ebstein’s anomaly.
Conclusion: The prevalence of WPW syndrome in our cohort of asymptomatic newborns was 0.1%. The syndrome was more frequent in boys, the accessory pathway was mostly left-sided, and was associated with changes in several ECG parameters, but generally not associated with structural heart disease. A striking observation was, that the WPW pattern in the majority of children could not be reproduced on follow-up ECGs at a mean age of three years, suggesting either that the ECG pattern is intermittent, or normalization occurs.
