title: Prolonged atrium electromechanical interval is associated with stroke in patients with atrial fibrillation after catheter ablation.
abstract: BACKGROUND
  Atrial fibrillation (AF) is associated with increased risk of embolic stroke. Catheter ablation of AF provides an effective therapy for patients with symptomatic and drug-refractory AF. The aim of this study was to evaluate whether the atrial electromechanical interval is useful in identifying patients at risk of stroke after successful catheter ablation.
  
  
  RESULTS
  A total of 279 AF patients who received catheter ablation and showed no evidence of recurrences were enrolled. Electromechanical interval (PA-PDI) was determined as the time interval from the initiation of P wave deflection to the peak of mitral inflow A wave on pulse wave Doppler imaging. The PA-PDI interval was measured for each patient after the 3-month blanking period of catheter ablation. The clinical endpoint was the occurrence of ischemic stroke. During the follow-up of 46.5 ± 17.2 months, 6 patients suffered from ischemic strokes. Patients with strokes had higher CHA2DS2-VASc scores and longer PA-PDI intervals (138.7 ± 12.4 ms vs 161.2 ± 7.7 ms, P value < 0.001) compared to those without strokes. At a cutoff point of 150 ms identified by ROC curve, the positive and negative predictive values of the PA-PDI interval to predict stroke were 86.7% and 100%, respectively. The PA-PDI interval improved the predictive performance of the CHA2DS2-VASc score, and the area under the ROC curve increased from 0.75 to 0.85.
  
  
  CONCLUSIONS
  Our results suggest that the PA-PDI interval is a useful tool to identify patients with high risk of stroke after successful catheter ablation of AF.
authors.affiliation: Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Tze-Fan
authors.initials: TF
authors.lastname: Chao
authors.forename: Yenn-Jiang
authors.initials: YJ
authors.lastname: Lin
authors.forename: Hsuan-Ming
authors.initials: HM
authors.lastname: Tsao
authors.forename: Shih-Lin
authors.initials: SL
authors.lastname: Chang
authors.forename: Li-Wei
authors.initials: LW
authors.lastname: Lo
authors.forename: Yu-Feng
authors.initials: YF
authors.lastname: Hu
authors.forename: Ta-Chuan
authors.initials: TC
authors.lastname: Tuan
authors.forename: Cheng-Hung
authors.initials: CH
authors.lastname: Li
authors.forename: Hung-Yu
authors.initials: HY
authors.lastname: Chang
authors.forename: Tsu-Juey
authors.initials: TJ
authors.lastname: Wu
authors.forename: Wen-Chung
authors.initials: WC
authors.lastname: Yu
authors.forename: Shih-Ann
authors.initials: SA
authors.lastname: Chen
mesh_terms: D000328:Adult; D000368:Aged; D019540:Area Under Curve; D001281:Atrial Fibrillation / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D016275:Atrial Function; D002545:Brain Ischemia / Q000209:etiology* / Q000503:physiopathology; D017115:Catheter Ablation / Q000009:adverse effects*; D016009:Chi-Square Distribution; D018619:Echocardiography, Doppler, Pulsed; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012372:ROC Curve; D018570:Risk Assessment; D012307:Risk Factors; D020521:Stroke / Q000209:etiology* / Q000503:physiopathology; D013997:Time Factors; D016896:Treatment Outcome