title: Validity of Electrocardiographic QT Interval in Predicting Left Ventricular Diastolic Dysfunction in Patients with Suspected Heart Failure.
abstract: OBJECTIVE
  To determine the validity of electrocardiographic QT interval in predicting left ventricular diastolic dysfunction in patients with suspected heart failure using echocardiogram as the gold standard.
  
  
  METHODS
  Cross-sectional validation study.
  
  
  METHODS
  AFIC-NIHD, Rawalpindi, from December 2012 to June 2013.
  
  
  METHODS
  Patients with suspected heart failure undergoing 12-lead electrocardiogram and echocardiography were inducted. All electrocardiograms were analyzed by a single trained reader unaware of the echocardiographic findings. QTc interval was calculated according to the published guidelines. All patients underwent a complete M mode, 2 dimensional, Doppler, and tissue Doppler echocardiography using aiE33 ultrasound system and diastolic dysfunction was calculated.
  
  
  RESULTS
  Three hundred patients were studied. Descriptive statistics of age was 61.42 years ±10.43. Of all the patients 218 patients (72.7%) were male and 82 patients were female (27.3%). Mean QT interval (msec) was 427.29 ±54.69. One hundred and eighty patients (60.0%) had diastolic dysfunction and 120 patients (40%) had no diastolic dysfunction. The sensitivity of electrocardiographic QTc interval in predicting diastolic dysfunction was 71.11% and specificity was 88.11%.
  
  
  CONCLUSIONS
  Prolonged electrocardiographic QTc interval in patients with suspected heart failure is a useful tool in predicting diastolic dysfunction.
authors.affiliation: Department of Cardiology, Armed Forces Institute of Cardiology (AFIC), Rawalpindi.
authors.forename: Hamid Sharif
authors.initials: HS
authors.lastname: Khan
authors.affiliation: Department of Cardiology, Armed Forces Institute of Cardiology (AFIC), Rawalpindi.
authors.forename: Imran
authors.initials: I
authors.lastname: Iftikhar
authors.affiliation: Department of Cardiology, Armed Forces Institute of Cardiology (AFIC), Rawalpindi.
authors.forename: Qaiser
authors.initials: Q
authors.lastname: Khan
mesh_terms: D000368:Aged; D003430:Cross-Sectional Studies; D003971:Diastole; D004452:Echocardiography; D015150:Echocardiography, Doppler / Q000379:methods*; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D006333:Heart Failure / Q000150:complications* / Q000503:physiopathology; D006801:Humans; D008133:Long QT Syndrome / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000503:physiopathology