title: Alterations of pressure waveforms along the coronary arteries and the effect of microcirculatory vasodilation.
abstract: OBJECTIVE
  We sought to investigate the differences of pressure waveforms at a distal point of an epicardial coronary artery comparatively to the ostium and to assess the effect of microcirculatory vasodilation on them.
  
  
  BACKGROUND
  Pressure waveforms in the systematic circulation and their alterations along the aorta due to wave reflections from the periphery have been extensively studied. However, similar data regarding intracoronary pressure waveforms and the effects of coronary microcirculation on them are limited.
  
  
  METHODS
  In 18 patients who underwent diagnostic coronary angiogram or percutaneous coronary intervention in the left circumflex or the right coronary artery, we studied pressure waveforms recorded by a high-fidelity pressure wire, which was advanced to the ostium and to a distal site of the free of significant lesions left anterior descending coronary artery. Pressure recording was performed both at rest and at hyperemia induced by intravenous infusion of adenosine. Analysis of pressure waveforms at the frequency domain was performed with Fast Fourier Transform.
  
  
  RESULTS
  At baseline conditions, distal pressure waveforms were characterized by higher pulsatility, higher presystolic wave and higher amplitude of the 11th to the 15th harmonics. Hyperemia increased the pulsatility, compressed the notch and decreased the amplitude of higher than the 10th harmonics of distal waveforms.
  
  
  CONCLUSIONS
  This study identifies differences of pressure waveforms between proximal and distal sites of free of significant lesions coronary arteries, which are affected by the status of coronary microcirculation and may therefore facilitate assessment of microvascular disease.
authors.affiliation: First Department of Cardiology, Athens Medical School, Hippokratio Hospital, 114 Vasilisis Sofias Ave, Athens 11527, Greece.
authors.forename: Manolis
authors.initials: M
authors.lastname: Vavuranakis
authors.forename: Ilias
authors.initials: I
authors.lastname: Stamatopoulos
authors.forename: Theodore G
authors.initials: TG
authors.lastname: Papaioannou
authors.forename: Stavros
authors.initials: S
authors.lastname: Nikolopoulos
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Toutouzas
authors.forename: Christodoulos
authors.initials: C
authors.lastname: Stefanadis
mesh_terms: D000241:Adenosine; D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000502:physiology*; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000503:physiopathology*; D003326:Coronary Circulation / Q000502:physiology*; D003331:Coronary Vessels / Q000502:physiology*; D005260:Female; D006801:Humans; D006940:Hyperemia / Q000503:physiopathology; D008297:Male; D008833:Microcirculation / Q000502:physiology; D008875:Middle Aged; D011673:Pulsatile Flow / Q000502:physiology; D014664:Vasodilation / Q000187:drug effects / Q000502:physiology*; D014665:Vasodilator Agents
chemical_list: D014665:Vasodilator Agents; D000241:Adenosine