title: Epicardial and microvascular coronary vasomotor dysfunction and its relation to myocardial ischemic burden in patients with non-obstructive coronary artery disease.
abstract: To assess the relative contribution of epicardial endothelium-dependent (EDD) and microvascular endothelium-independent (EIMVD) coronary vasomotor dysfunction to the extent of myocardial ischemia in patients with normal angiograms or non-obstructive coronary artery disease (NOCAD).
  
  
  
  Coronary vasomotion was evaluated by quantitative angiography and blood flow (CBF) measurements during intracoronary acetylcholine, nitroglycerine, and adenosine in 101 patients. Myocardial SPECT ischemic burden was evaluated by semi-quantitative scoring of summed stress (SSS) and summed ischemic (SDS) perfusion defect size.
  
  
  
  Coronary vasomotor dysfunction was found in most patients (83; 77%) with a divergent behavior of EDD and EIMVD in one half of them (52.4%). There was no significant difference in SDS between patients with and without EIMVD, whereas SDS was significantly greater in subjects with EDD as compared to patients with normal response to acetylcholine (4.31 ± 2.44 vs 1.35 ± 1.45; P < .0001). Patients with EDD, either alone or in combination with EIMVD, had significantly higher SSS as compared to patients with lone EIMVD or normal vasomotor function (8.50 ± 5.32; 5.55 ± 3.21; 2.60 ± 2.14; and 1.74 ± 1.66, respectively; P < .0001). Acetylcholine CBF correlated inversely with both SDS (r = -0.545; P < .001) and SSS (r = 0.538; P < .001).
  
  
  
  In NOCAD patients with symptoms and signs of myocardial ischemia, vasomotor dysfunction is common. EDD is associated with greater extent of ischemia as compared to isolated EIMVD. Thus, assessment of both EIMVD and EDD is needed to recognize mechanisms of ischemia and identify patients with greater ischemic burden.
authors.affiliation: Department of Cardiology, Ospedale di Circolo & Fondazione Macchi, University Hospital-Varese, Università dell'Insubria, Viale Borri 57, 21100, Varese, Italy. edoardo.verna@virgilio.it.
authors.forename: Edoardo
authors.initials: E
authors.lastname: Verna
authors.affiliation: Department of Cardiology, Ospedale di Circolo & Fondazione Macchi, University Hospital-Varese, Università dell'Insubria, Viale Borri 57, 21100, Varese, Italy.
authors.forename: Sergio
authors.initials: S
authors.lastname: Ghiringhelli
authors.affiliation: Department of Cardiology, Ospedale di Circolo & Fondazione Macchi, University Hospital-Varese, Università dell'Insubria, Viale Borri 57, 21100, Varese, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Provasoli
authors.affiliation: Nuclear Medicine, Ospedale di Circolo & Fondazione Macchi, University Hospital, Università dell'Insubria, Varese, Italy.
authors.forename: Simone
authors.initials: S
authors.lastname: Scotti
authors.affiliation: Department of Cardiology, Ospedale di Circolo & Fondazione Macchi, University Hospital-Varese, Università dell'Insubria, Viale Borri 57, 21100, Varese, Italy.
authors.forename: Jorge
authors.initials: J
authors.lastname: Salerno-Uriarte
mesh_terms: D000328:Adult; D000368:Aged; D003324:Coronary Artery Disease / Q000503:physiopathology*; D003326:Coronary Circulation; D003331:Coronary Vessels / Q000503:physiopathology*; D004730:Endothelium, Vascular / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D055806:Microvessels / Q000503:physiopathology; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000503:physiopathology*; D010496:Pericardium / Q000503:physiopathology*
keywords: Coronary artery disease; Coronary blood flow; Endothelial dysfunction; Microvascular disease; Myocardial perfusion imaging (SPECT)