title: Myocardial blood flow in patients with dilated cardiomyopathy: quantitative assessment with velocity-encoded cine magnetic resonance imaging of the coronary sinus.
abstract: OBJECTIVE
  To quantify global myocardial perfusion using magnetic resonance imaging (MRI) in patients with heart failure due to idiopathic dilated cardiomyopathy (IDC) and to compare myocardial perfusion and microvascular reactivity with healthy subjects.
  
  
  METHODS
  A total of 19 subjects (healthy volunteers (N = 12) and IDC patients (N = 7)) were studied using cine MRI to measure left ventricular (LV) mass and a velocity-encoded cine MRI technique to measure coronary sinus flow at rest and after dipyridamole-induced hyperemia. Absolute values of total myocardial blood flow (MBF) were calculated from coronary sinus flow and LV mass.
  
  
  RESULTS
  At baseline, MBF was not significantly different in patients with IDC (0.48 +/- 0.07 mL/minute/g) and healthy subjects (0.55 +/- 0.19 mL/minute/g, P= 0.41). After dipyridamole administration, MBF in IDC patients increased to a level significantly less than that in normal volunteers (1.05 +/- 0.35 mL/minute/g vs. 1.99 +/- 1.05 mL/minute/g, P < 0.05). Consequently, MBF reserve was impaired in patients with IDC (2.19 +/- 0.77) compared to that in healthy subjects (3.51 +/- 1.29, P < 0.05). A moderate correlation was found between MBF reserve and LV ejection fraction (r = 0.48, P < 0.05).
  
  
  CONCLUSIONS
  MBF reserve is reduced in patients with IDC, indicating that coronary microcirculatory flow is impaired. This integrated MRI approach allows quantitative measurement of global MBF in humans and may have the potential to study the effects of pharmacological interventions on myocardial perfusion.
authors.affiliation: Department of Radiology, University of California, San Francisco, California 94143-0628, USA.
authors.forename: Norbert
authors.initials: N
authors.lastname: Watzinger
authors.forename: Gunnar K
authors.initials: GK
authors.lastname: Lund
authors.forename: Maythem
authors.initials: M
authors.lastname: Saeed
authors.forename: Gautham P
authors.initials: GP
authors.lastname: Reddy
authors.forename: Philip A
authors.initials: PA
authors.lastname: Araoz
authors.forename: Ming
authors.initials: M
authors.lastname: Yang
authors.forename: Alan B
authors.initials: AB
authors.lastname: Schwartz
authors.forename: Martin
authors.initials: M
authors.lastname: Bedigian
authors.forename: Charles B
authors.initials: CB
authors.lastname: Higgins
mesh_terms: D000328:Adult; D000368:Aged; D002311:Cardiomyopathy, Dilated / Q000175:diagnosis / Q000503:physiopathology*; D003326:Coronary Circulation / Q000502:physiology*; D004176:Dipyridamole; D005260:Female; D006333:Heart Failure / Q000503:physiopathology; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008833:Microcirculation / Q000503:physiopathology; D008875:Middle Aged; D014665:Vasodilator Agents
chemical_list: D014665:Vasodilator Agents; D004176:Dipyridamole