title: Strain measurements during adenosine triphosphate infusion before and after percutaneous coronary intervention.
abstract: BACKGROUND
  In regional myocardial ischemia, contractile delay develops, which can be assessed by measuring time to peak strain (TPS) on tissue Doppler imaging. The aims of the present study were to clarify the usefulness of TPS measurements during adenosine triphosphate (ATP) stress in assessing myocardial ischemia and to evaluate whether prolongation of TPS disappears immediately after percutaneous coronary intervention (PCI) or not.
  
  
  RESULTS
  A total of 26 patients underwent strain measurements before and after PCI. Corrected TPS for heart rate (TPSc) in target regions and in control regions were measured both at baseline and during ATP infusion. TPSc ratio was calculated as a ratio of TPSc during ATP stress to TPSc at baseline. TPSc in the target region significantly increased during ATP infusion before PCI, which was significantly longer than hyperemic TPSc in control regions. Accordingly, TPSc ratio in the target regions before PCI was significantly greater than that in control regions (1.22+/-0.17 vs 0.96+/-0.09, respectively, P<0.0001). Following PCI, the TPSc ratio in the target regions significantly decreased to 0.98+/-0.05 (P<0.0001). Receiver operating characteristic curve analysis provided a cut-off of 1.04 in TPSc ratio for detecting myocardial ischemia with a sensitivity of 93% and specificity of 93%.
  
  
  CONCLUSIONS
  TPS measurements during ATP stress differentiated target from control myocardium before PCI. The prolongation of TPSc disappeared immediately after PCI.
authors.affiliation: Cardiology, Tokyo Women's Medical University, Tokyo 162-8666, Japan.
authors.forename: Motoko
authors.initials: M
authors.lastname: Hosaka
authors.forename: Atsushi
authors.initials: A
authors.lastname: Takagi
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Takagi
authors.forename: Kyomi
authors.initials: K
authors.lastname: Ashihara
authors.forename: Nobuhisa
authors.initials: N
authors.lastname: Hagiwara
mesh_terms: D000255:Adenosine Triphosphate / Q000008:administration & dosage*; D000368:Aged; D000787:Angina Pectoris; D015906:Angioplasty, Balloon, Coronary; D015150:Echocardiography, Doppler / Q000379:methods* / Q000592:standards; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000175:diagnosis*; D012372:ROC Curve
chemical_list: D000255:Adenosine Triphosphate