title: Coronary flow reserve as a link between exercise capacity, cardiac systolic and diastolic function.
abstract: BACKGROUND
  Decreased coronary flow reserve (CFR) is associated with increased risk of adverse cardiovascular events. We sought to investigate how CFR from left anterior descending (LAD) coronary artery reflects clinical markers of cardiac function.
  
  
  METHODS
  We enrolled 400 patients referred for myocardium perfusion scintigraphy due to chest pain at Sahlgrenska University Hospital in Gothenburg, Sweden. Transthoracic echocardiography including adenosine-assisted CFR in LAD was performed at a separate occasion.
  
  
  RESULTS
  Median age was 62years (range 32-83) and 47% were female. Prior myocardial infarction had occurred in 28% of the population. In adjusted multivariate models, CFR in LAD was associated with echocardiography left ventricle ejection fraction at rest (β=0.97, p=0.033) as well as under stress (β=1.52, p=0.0056) and maximum exercise capacity (β=6.27, p=0.026). CFR in LAD outweighed left ventricle ejection fraction as the determinant of maximum exercise capacity. Hyperaemic diastolic mitral annulus peak velocity measured by vector velocity imaging was inversely associated with LAD CFR (β=-0.39, p=0.0077). In subgroup analyses these findings were associated with normal coronary perfusion in myocardium perfusion scintigraphy.
  
  
  CONCLUSIONS
  In patients with angina-like symptoms CFR measured in LAD reflects well both systolic and diastolic cardiac function emphasizing the essential role of myocardial microvascular circulation in cardiac physiology.
authors.affiliation: Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden; AstraZeneca R&D, Mölndal, Sweden; Heart Centre, University of Turku, Turku, Finland.
authors.forename: Juuso I
authors.initials: JI
authors.lastname: Blomster
authors.affiliation: Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden; Department of Clinical Physiology, Sahlgrenska University Hospital, Gothenburg, Sweden.
authors.forename: Sara
authors.initials: S
authors.lastname: Svedlund
authors.affiliation: Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.
authors.forename: Helena
authors.initials: H
authors.lastname: U Westergren
authors.affiliation: Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden; AstraZeneca R&D, Mölndal, Sweden; Department of Clinical Physiology, Sahlgrenska University Hospital, Gothenburg, Sweden. Electronic address: li-ming.gan@gu.se.
authors.forename: Li-Ming
authors.initials: LM
authors.lastname: Gan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002637:Chest Pain / Q000209:etiology* / Q000503:physiopathology; D003971:Diastole; D004452:Echocardiography; D005080:Exercise Test; D005260:Female; D053805:Fractional Flow Reserve, Myocardial; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000503:physiopathology; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D013599:Systole; D016277:Ventricular Function, Left
keywords: Cardiac imaging; Coronary flow reserve; Diastolic function; Echocardiography; Systolic function