title: Strain rate imaging pre- and post-percutaneous coronary intervention: a potential role in the objective detection of ischaemia in exercise stress echocardiography.
abstract: OBJECTIVE
  To determine the feasibility of strain rate imaging (SRI) in the objective detection of exercise-induced ischaemia.
  
  
  RESULTS
  Sixteen patients undergoing elective percutaneous coronary intervention (PCI) underwent treadmill exercise stress echocardiography (ESE) pre- and post-PCI. Measurement of systolic SRI parameters was attempted in all myocardial segments at baseline, peak stress, and in recovery. Segments were divided into those supplied by target (Group 1) and non-target vessels (Group 2). Percutaneous coronary intervention was successful in all patients. In Group 1, there was no significant difference in post-systolic strain rate (SRps) at baseline or at peak stress but there was significantly greater SRps pre-PCI compared with post-PCI at 30 min into recovery (-0.37 +/- 0.53 vs. -0.07 +/- 0.44 s(-1), P = 0.004). There were similar findings with the SRps index [ratio of SRps:peak systolic strain rate (SRsys)]. Group 2 segments did not demonstrate any significant differences in SRI parameters pre- and post-PCI. At peak exercise pre-PCI, Group 1 segments had significantly delayed time to SRsys compared with Group 2 (0.12 +/- 0.05 vs. 0.09 +/- 0.05 s, P = 0.013), a difference that was abolished post-PCI.
  
  
  CONCLUSIONS
  This suggests a potential role for SRI in the objective detection of exercise-induced ischaemia by echocardiography at peak stress and during recovery at the time of improved image quality.
authors.affiliation: Cardiothoracic Division, The James Cook University Hospital, Middlesbrough TS4 3BW, UK. jeet.thambyrajah@stees.nhs.uk
authors.forename: J
authors.initials: J
authors.lastname: Thambyrajah
authors.forename: K
authors.initials: K
authors.lastname: Vijayalakshmi
authors.forename: R J
authors.initials: RJ
authors.lastname: Graham
authors.forename: A J
authors.initials: AJ
authors.lastname: Turley
authors.forename: M A
authors.initials: MA
authors.lastname: de Belder
authors.forename: M J
authors.initials: MJ
authors.lastname: Stewart
mesh_terms: D015906:Angioplasty, Balloon, Coronary; D025401:Echocardiography, Stress; D005080:Exercise Test; D017079:Exercise Tolerance; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging* / Q000628:therapy*; D013599:Systole; D013997:Time Factors