title: The role of the atrial electromechanical delay in predicting atrial fibrillation in beta-thalassemia major patients.
abstract: BACKGROUND
  Paroxysmal atrial tachyarrhythmias frequently occur in beta-thalassemia major (β-TM) patients. The aim of the current study was to evaluate the atrial electromechanical delay (AEMD) in a large β-TM population with normal cardiac function and its relationship to atrial fibrillation (AF) onset.
  
  
  METHODS
  Eighty β-TM patients (44 men, 36 women), with a mean age of 36.2 ± 11.1 years, and 80 healthy subjects used as controls, matched for age and gender, were studied for the occurrence of AF during a 5-year follow-up, through 30-day external loop recorder (ELR) monitoring performed every 6 months. Intra-AEMD and inter-AEMD of both atria were measured through tissue Doppler echocardiography. P-wave dispersion (PD) was carefully measured using 12-lead electrocardiogram (ECG).
  
  
  RESULTS
  Compared to the healthy control group, the β-TM patients showed a statistically significant increase in inter-AEMD, intra-left AEMD, maximum P-wave duration, and PD. Dividing the β-TM group into two subgroups (patients with or without AF), the inter-AEMD, intra-left AEMD, maximum P-wave duration, and PD were significantly higher in the subgroup with AF compared to the subgroup without AF. There were significant good correlations of intra-left AEMD and inter-AEMD with PD. A cut-off value of 40.1 ms for intra-left AEMD had a sensitivity of 76.2% and a specificity of 97.5% in identifying β-TM patients with AF risk. A cut-off value of 44.8 ms for inter-AEMD had a sensitivity of 81.2% and a specificity of 98.7% in identifying this category of patients.
  
  
  CONCLUSIONS
  Our results showed that the echocardiographic atrial electromechanical delay indices (intra-left and inter-AEMD) and the PD were significantly increased in β-TM subjects with normal cardiac function. PD and AEMD represent non-invasive, inexpensive, useful, and simple parameters to assess the AF risk in β-TM patients.
authors.affiliation: Chair of Cardiology, Second University of Naples - Monaldi Hospital, Naples, Italy. anna_rago@alice.it.
authors.forename: Anna
authors.identifier: http://orcid.org/0000-0001-9252-2997
authors.initials: A
authors.lastname: Rago
authors.affiliation: Chair of Cardiology, Second University of Naples - Monaldi Hospital, Naples, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Russo
authors.affiliation: Chair of Cardiology, Second University of Naples - Monaldi Hospital, Naples, Italy.
authors.forename: Andrea Antonio
authors.initials: AA
authors.lastname: Papa
authors.affiliation: H.T. MED Pozzuoli (NA), Naples, Italy.
authors.forename: Carmine
authors.initials: C
authors.lastname: Ciardiello
authors.affiliation: Internal Medicine Unit, Cardarelli Hospital, Naples, Italy.
authors.forename: Bruno
authors.initials: B
authors.lastname: Pannone
authors.affiliation: Internal Medicine Unit, Cardarelli Hospital, Naples, Italy.
authors.forename: Maria Carolina
authors.initials: MC
authors.lastname: Mayer
authors.affiliation: Chair of Cardiology, Second University of Naples - Monaldi Hospital, Naples, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Cimmino
authors.affiliation: Chair of Cardiology, Second University of Naples - Monaldi Hospital, Naples, Italy.
authors.forename: Gerardo
authors.initials: G
authors.lastname: Nigro
mesh_terms: D000328:Adult; D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000453:epidemiology*; D015984:Causality; D015897:Comorbidity; D004452:Echocardiography / Q000379:methods*; D004562:Electrocardiography / Q000379:methods*; D056966:Excitation Contraction Coupling; D005260:Female; D006801:Humans; D015994:Incidence; D007558:Italy / Q000453:epidemiology; D008297:Male; D015203:Reproducibility of Results; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D017086:beta-Thalassemia / Q000175:diagnosis* / Q000453:epidemiology*
keywords: Atrial electromechanical delay; Atrial fibrillation; Beta-thalassemia major; P-wave dispersion