title: Impaired myocardial perfusion and perfusion reserve associated with increased coronary resistance in persistent idiopathic atrial fibrillation.
abstract: OBJECTIVE
  Patients with atrial fibrillation (AF) present with symptoms of myocardial ischaemia despite exclusion of coronary artery disease. A small vessel disease has been suggested. We quantified myocardial perfusion, perfusion reserve, and coronary vascular resistance (CVR) in AF patients using positron emission tomography (PET).
  
  
  RESULTS
  Twenty-five male patients (age: 58 +/- 13 years) with persistent idiopathic AF were compared with 13 age- and risk-matched male controls (age: 56 +/- 8 years). Using H(2)(15)O-PET, myocardial blood flow (MBF) was quantified at rest, at hyperaemia (adenosine), and during cold-pressor-testing (CPT). Scans were repeated 4.1 +/- 2.3 months after cardioversion in 10 AF patients. In AF, resting MBF (0.95 +/- 0.19 vs. 1.14 +/- 0.22 mL/min/mL; P = 0.009), hyperaemic MBF (2.07 +/- 0.80 vs. 3.33 +/- 0.78 mL/min/mL; P < 0.001), and MBF under CPT (0.90 +/- 0.25 vs. 1.14 +/- 0.25 mL/min/mL; P < 0.014) were significantly reduced compared with matched controls. Hyperaemic CVR was increased in AF (47 +/- 21 vs. 29 +/- 7 mmHg x mL/min/mL; P = 0.012) but unchanged at rest and under CPT. After cardioversion, resting MBF and MBF under CPT in AF were similar to matched controls, however, hyperaemic MBF and CVR were not recovered.
  
  
  CONCLUSIONS
  In AF, MBF at baseline, at hyperaemia, and at CPT is reduced, whereas CVR under hyperaemic conditions is increased. Following electrical cardioversion, these findings are partly reversible and therefore most likely secondary to the arrhythmia.
authors.affiliation: Department of Nuclear Medicine, University of Münster, Albert-Schweitzer-Str. 33, D-48149 Münster, Germany.
authors.forename: Felix T
authors.initials: FT
authors.lastname: Range
authors.forename: Michael
authors.initials: M
authors.lastname: Schäfers
authors.forename: Tayfun
authors.initials: T
authors.lastname: Acil
authors.forename: Klaus P
authors.initials: KP
authors.lastname: Schäfers
authors.forename: Peter
authors.initials: P
authors.lastname: Kies
authors.forename: Matthias
authors.initials: M
authors.lastname: Paul
authors.forename: Sven
authors.initials: S
authors.lastname: Hermann
authors.forename: Betty
authors.initials: B
authors.lastname: Brisse
authors.forename: Günter
authors.initials: G
authors.lastname: Breithardt
authors.forename: Otmar
authors.initials: O
authors.lastname: Schober
authors.forename: Thomas
authors.initials: T
authors.lastname: Wichter
mesh_terms: D000328:Adult; D000367:Age Factors; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D003326:Coronary Circulation / Q000502:physiology*; D004452:Echocardiography; D004554:Electric Countershock; D004730:Endothelium, Vascular; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D045265:Natriuretic Peptides / Q000097:blood; D049268:Positron-Emission Tomography; D012307:Risk Factors; D014655:Vascular Resistance / Q000502:physiology*
chemical_list: D000889:Anti-Arrhythmia Agents; D045265:Natriuretic Peptides