title: Pattern of exercise-induced ST change is related to coronary flow reserve in patients with chest pain and normal coronary angiogram.
abstract: OBJECTIVE
  To evaluate the usefulness of exercise treadmill test in determining the true microvasculature-induced ischemia, we compared the pattern of ST depression with coronary flow reserve (CFR) using transthoracic Doppler echocardiography (TTE) in patients with chest pain and normal coronary angiogram.
  
  
  METHODS
  Fifty-nine subjects (M/F=21:38, mean age 55+/-9 years) with chest pain and normal coronary angiogram underwent maximal symptom-limited exercise treadmill test (ETT). CFR was estimated with TTE and dipyridamole. Patients with a history of acute myocardial infarction, regional wall motion abnormalities, hypertrophic cardiomyopathy, ejection fraction less than 50%, or primary valvular heart disease were excluded from this study.
  
  
  RESULTS
  No ST change was observed in 20 of 59 (34%) patients, up slope depression was observed in 20 (34%), flat depression in 13 (22%), and down slope depression in 6 (10%). Eleven of thirty nine (28%) exercise positive patients had decreased CFR <2.1. CFR was 3.1+/-0.6 in group with no ST change, 3.1+/-0.6 in group with up slope depression, 2.1+/-0.6 in group with flat depression (p<0.05 versus group with no change and group with upslope depression, respectively), and 2.0+/-0.4 in group with down slope depression (p<0.05 versus group with no change and group with up slope depression, respectively). Flat to down slope depression of ST change during ETT had sensitivity of 58% and specificity of 95% for predicting CFR <2.1.
  
  
  CONCLUSIONS
  Flat and down slope depression of ST segment during ETT might increase the sensitivity and specificity to detect the true microvasculature-induced ischemia that is defined as CFR less than 2.1 in patients with chest pain and normal coronary angiogram.
authors.affiliation: Department of Internal Medicine, College of Medicine, The Catholic University of Korea, #62 Yoido-dong, Youngdungpo-ku, St. Mary's Hospital, Seoul, 150-713, South Korea. younhj@catholi.ac.kr
authors.forename: Ho-Joong
authors.initials: HJ
authors.lastname: Youn
authors.forename: Chul-Soo
authors.initials: CS
authors.lastname: Park
authors.forename: Eun-Joo
authors.initials: EJ
authors.lastname: Cho
authors.forename: Hae-Ok
authors.initials: HO
authors.lastname: Jung
authors.forename: Hui-Kyung
authors.initials: HK
authors.lastname: Jeon
authors.forename: Jong-Min
authors.initials: JM
authors.lastname: Lee
authors.forename: Yong-Seok
authors.initials: YS
authors.lastname: Oh
authors.forename: Wook-Sung
authors.initials: WS
authors.lastname: Chung
authors.forename: Jae-Hyung
authors.initials: JH
authors.lastname: Kim
authors.forename: Kyu-Bo
authors.initials: KB
authors.lastname: Choi
authors.forename: Soon-Jo
authors.initials: SJ
authors.lastname: Hong
mesh_terms: D000368:Aged; D001783:Blood Flow Velocity; D002302:Cardiac Output / Q000502:physiology*; D015150:Echocardiography, Doppler; D004562:Electrocardiography; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D017566:Microvascular Angina / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008875:Middle Aged; D012680:Sensitivity and Specificity