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Ventricular repolarisation during exercise challenge occurring late after Kawasaki disease
Hugo Gravel1, Nagib Dahdah, Anne Fournier
1Division of Pediatric Cardiology, Centre Hospitalier Universitaire Sainte-Justine, 3175 Chemin de la Côte-Sainte-Catherine, Montreal, Quebec H3T 1C5, Canada.
Pediatric Cardiology
|February 22, 2012
Summary
Children with a history of Kawasaki disease (KD) show abnormal heart repolarization during exercise. This QT dispersion (QTd) abnormality is present even years after KD, regardless of coronary complications.
Area of Science:
- Pediatric Cardiology
- Electrophysiology
- Cardiovascular Research
Background:
- Kawasaki disease (KD) can lead to coronary artery abnormalities.
- Repolarization abnormalities, like increased QT dispersion (QTd), are known in adults with coronary artery disease.
- QTd has been reported at rest in children post-KD, but exercise-induced changes are unstudied.
Purpose of the Study:
- To investigate the pattern of QT dispersion (QTd) response to exercise testing in children with a history of Kawasaki disease (KD).
- To determine if exercise unmasks repolarization abnormalities in children late after KD, irrespective of coronary sequelae.
Main Methods:
- Compared QT dispersion (QTd) during exercise testing in children with no coronary complications, coronary dilation, and severe complications post-KD, against healthy controls.
- Measured QT intervals from QRS onset to T wave apex (QTa) and end (QTe).
- Assessed resting and exercise-induced QTd abnormalities.
Main Results:
- Resting QTd was significantly increased in KD subjects compared to controls.
- Abnormal QTd was present in 29-36% of KD patients, evenly distributed across severity groups.
- Exercise testing revealed significantly altered QTd response in KD patients, independent of resting QTd or coronary sequelae.
Conclusions:
- Abnormal resting and exercise-induced repolarization are detectable in children long after Kawasaki disease.
- These repolarization abnormalities are present irrespective of the severity of coronary sequelae following KD.
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