title: A novel method for left anterior coronary artery flow velocity assessment by transthoracic echocardiography at the peak of a supine bicycle test.
abstract: BACKGROUND
  Assessment of coronary flow is only performed during pharmacological tests. Supine bicycle tests permit the visualization of coronary flow assessments during exercise.
  
  
  OBJECTIVE
  To assess the parameters of coronary flow in the left anterior descending artery (LAD) during exercise, which could be a sign of significant LAD narrowing.
  
  
  METHODS
  A total of 253 patients were enrolled: Group 1, 186 non-selective participants before undergoing a coronary angiography; and Group 2, 67 controls without coronary artery disease (CAD). All the patients performed a supine bicycle echocardiography test. Coronary flow velocities and coronary flow velocity reserve (CFVR) were measured at the mid-segment of the LAD during exercise. Patients in Group 1 underwent a coronary angiography.
  
  
  RESULTS
  In comparison with participants without significant LAD stenosis, patients with LAD lesions had a lower ΔV (16 ± 21 vs. 27 ± 20 cm/s, P < 0.04) and a lower CFVR (1.5 ± 0.8 vs. 2.0 ± 0.6, P < 0.004). In comparison with patients without significant proximal LAD stenosis, the patients with proximal LAD lesions had a lower flow velocity at the peak of exercise (49 ± 32 vs. 61 ± 19 cm/s, P < 0.02), a lower ΔV (13 ± 19 vs. 26 ± 22 cm/s, P < 0.004), and a lower CFVR (1.4 ± 0.6 vs. 1.9 ± 0.7, P < 0.0001). In comparison with the control group, the patients with LAD stenosis had a lower flow velocity at the peak of exercise, a lower ΔV, and a lower CFVR.
  
  
  CONCLUSIONS
  Non-invasive CFVR measurement in the LAD could provide valuable additional information to a conventional echocardiography exercise test. In routine clinical practice, CFVR is sufficient for a diagnosis of severe stenosis.
authors.affiliation: Medika Cardiocenter, Saint Petersburg, Russian Federation angela.zagatina@centrum.cz.
authors.forename: Angela
authors.initials: A
authors.lastname: Zagatina
authors.affiliation: Medika Cardiocenter, Saint Petersburg, Russian Federation.
authors.forename: Nadezhda
authors.initials: N
authors.lastname: Zhuravskaya
authors.affiliation: Egom Clinical and Translational Research Services, Halifax, NS, Canada.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Egom
authors.affiliation: Fifth Department of Internal Medicine, University Hospital, Bratislava, Slovak Republic.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Kovacova
authors.affiliation: Second Department of Internal Medicine, St. Anne's University Hospital and Masaryk University, Brno, Czech Republic.
authors.forename: Peter
authors.initials: P
authors.lastname: Kruzliak
mesh_terms: D001642:Bicycling / Q000502:physiology; D001783:Blood Flow Velocity; D016022:Case-Control Studies; D017023:Coronary Angiography; D003326:Coronary Circulation; D003327:Coronary Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D018619:Echocardiography, Doppler, Pulsed; D025401:Echocardiography, Stress; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged
keywords: Coronary flow reserve; LAD flow; coronary flow velocity; exercise echo; visualization of coronary artery