The 24-hour changes in the complexity of ventricular repolarization in hemodialysis (HD) patients were quantified by principal component analysis (PCA) of the T wave. The effects of dialysis sessions leading to different plasma potassium levels ('Klow' and 'Khigh') were analyzed. Forty-six Holter recordings were collected from twelve patients. PCA was applied to the T waves extracted from each beat. Repolarization complexity was quantified by the ratio of the second to the first eigenvalue (PCA ratio). Hemodialysis caused a significant increase in the PCA ratio (+50% at the end of the sessions), which recovered to the basal value during the first hour post-dialysis. In the last two hours of dialysis PCA ratio was significantly higher in Klow sessions than in Khigh ones. Results show a significant HD-induced increase of the T wave complexity, strongly related to the therapy-induced potassium depletion.
S. Severi, E. Grandi, G. Alessandrini, A. Santoro, S. Cavalcanti (2006). Principal Component Analysis of the T Wave: 24 Hour Monitoring of Repolarization Complexity in Dialysis Patients.
Principal Component Analysis of the T Wave: 24 Hour Monitoring of Repolarization Complexity in Dialysis Patients
SEVERI, STEFANO;GRANDI, ELEONORA;ALESSANDRINI, GIORGIA;SANTORO, ANTONIO;CAVALCANTI, SILVIO
2006
Abstract
The 24-hour changes in the complexity of ventricular repolarization in hemodialysis (HD) patients were quantified by principal component analysis (PCA) of the T wave. The effects of dialysis sessions leading to different plasma potassium levels ('Klow' and 'Khigh') were analyzed. Forty-six Holter recordings were collected from twelve patients. PCA was applied to the T waves extracted from each beat. Repolarization complexity was quantified by the ratio of the second to the first eigenvalue (PCA ratio). Hemodialysis caused a significant increase in the PCA ratio (+50% at the end of the sessions), which recovered to the basal value during the first hour post-dialysis. In the last two hours of dialysis PCA ratio was significantly higher in Klow sessions than in Khigh ones. Results show a significant HD-induced increase of the T wave complexity, strongly related to the therapy-induced potassium depletion.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
