title: Myocardial ischemia during mental stress: role of coronary artery disease burden and vasomotion.
abstract: BACKGROUND
  Mental stress-induced myocardial ischemia (MSIMI) is associated with adverse prognosis in patients with coronary artery disease (CAD), yet the mechanisms underlying this phenomenon remain unclear. We hypothesized that compared with exercise/pharmacological stress-induced myocardial ischemia (PSIMI) that is secondary to the atherosclerotic burden of CAD, MSIMI is primarily due to vasomotor changes.
  
  
  RESULTS
  Patients with angiographically documented CAD underwent 99mTc-sestamibi myocardial perfusion imaging at rest and following both mental and physical stress testing, performed on separate days. The severity and extent of CAD were quantified using the Gensini and Sullivan scores. Peripheral arterial tonometry (Itamar Inc) was used to assess the digital microvascular tone during mental stress as a ratio of pulse wave amplitude during speech compared with baseline. Measurements were made in a discovery sample (n = 225) and verified in a replication sample (n = 159). In the pooled (n = 384) sample, CAD severity and extent scores were not significantly different between those with and without MSIMI, whereas they were greater in those with compared with those without PSIMI (P < 0.04 for all). The peripheral arterial tonometry ratio was lower in those with compared with those without MSIMI (0.55 ± 0.36 versus 0.76 ± 0.52, P = 0.009). In a multivariable analysis, the peripheral arterial tonometry ratio was the only independent predictor of MSIMI (P = 0.009), whereas angiographic severity and extent of CAD independently predicted PSIMI.
  
  
  CONCLUSIONS
  The degree of digital microvascular constriction, and not the angiographic burden of CAD, is associated with MSIMI. Varying causes of MSIMI compared with PSIMI may require different therapeutic interventions that require further study.
authors.affiliation: Division of Cardiology, Department of Medicine, Emory University School of Medicine, Atlanta, GA.
authors.forename: Ronnie
authors.initials: R
authors.lastname: Ramadan
authors.forename: David
authors.initials: D
authors.lastname: Sheps
authors.forename: Fabio
authors.initials: F
authors.lastname: Esteves
authors.forename: A Maziar
authors.initials: AM
authors.lastname: Zafari
authors.forename: J Douglas
authors.initials: JD
authors.lastname: Bremner
authors.forename: Viola
authors.initials: V
authors.lastname: Vaccarino
authors.forename: Arshed A
authors.initials: AA
authors.lastname: Quyyumi
mesh_terms: D000368:Aged; D003324:Coronary Artery Disease / Q000150:complications* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000209:etiology*; D013315:Stress, Psychological / Q000150:complications*; D014661:Vasoconstriction
keywords: coronary disease; ischemia; mental stress; vasoconstriction