title: High-frequency QRS electrocardiogram predicts perfusion defects during myocardial perfusion imaging.
abstract: BACKGROUND
  Changes in high-frequency (HF) QRS components of the electrocardiogram (ECG) (150-250 Hz) are more sensitive than changes in conventional ST segments for detecting myocardial ischemia. We investigated the accuracy of 12-lead HF QRS ECG in detecting perfusion defects during adenosine tetrofosmin myocardial perfusion imaging (MPI).
  
  
  RESULTS
  12-lead HF QRS ECG recordings were obtained from 45 patients before and during adenosine technetium Tc 99m tetrofosmin MPI tests. Before the adenosine infusions, recordings of HF QRS were analyzed according to a morphologic score that incorporated the number, type, and location of reduced amplitude zones (RAZs) present in the 12 leads. During the adenosine infusions, recordings of HF QRS were analyzed according to the maximum percentage changes (in both the positive and negative directions) that occurred in root mean square voltage amplitudes within the 12 leads. The best set of prospective HF QRS criteria had a sensitivity of 94% and a specificity of 83% for correctly identifying the MPI result. The sensitivity of simultaneous ST-segment changes (18%) was significantly lower than that of any individual HF QRS criterion (P < .001).
  
  
  CONCLUSIONS
  Analysis of 12-lead HF QRS ECG is highly sensitive and reasonably specific for detecting perfusion defects during adenosine MPI stress tests and significantly more sensitive than analysis of conventional ST segments.
authors.affiliation: MD Anderson Cancer Center, Houston, TX 77030, USA. amrahman@mdanderson.org
authors.forename: M Atiar
authors.initials: MA
authors.lastname: Rahman
authors.forename: Alex
authors.initials: A
authors.lastname: Gedevanishvili
authors.forename: Yochai
authors.initials: Y
authors.lastname: Birnbaum
authors.forename: Laura
authors.initials: L
authors.lastname: Sarmiento
authors.forename: Waralee
authors.initials: W
authors.lastname: Sattam
authors.forename: Walter B
authors.initials: WB
authors.lastname: Kulecz
authors.forename: Todd T
authors.initials: TT
authors.lastname: Schlegel
mesh_terms: D000241:Adenosine; D000368:Aged; D002637:Chest Pain / Q000175:diagnosis; D003326:Coronary Circulation / Q000502:physiology*; D004562:Electrocardiography; D005080:Exercise Test; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology; D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D011300:Preoperative Care; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D012044:Regression Analysis; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D014665:Vasodilator Agents
chemical_list: D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D014665:Vasodilator Agents; C078700:technetium tc-99m tetrofosmin; D000241:Adenosine