Myocardial Ischemia During Mental Stress: Role of Coronary Artery Disease Burden and Vasomotion

• Type of Material: Article
• Authors: Ronnie Ramadan, Emory University; David Sheps, University of Florida; Fabio Esteves, Emory University; A. Maziar Zafari, Emory University; J. Douglas Bremner, Emory University; Viola Vaccarino, Emory University; Arshed Ali Quyyumi, Emory University
• Language: English
• Date: 2013-10-25
• Publisher: American Heart Association
• Publication Version: Final Published Version
• Copyright Statement: © 2013 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.
• License: Creative Commons Attribution-Noncommercial 3.0 Unported
• Final Published Version (URL): http://jaha.ahajournals.org/content/2/5/e000321
• Title of Journal or Parent Work: Journal of the American Heart Association
• ISSN: 2047-9980
• Volume: 2
• Issue: 5
• Grant/Funding Information: National Institutes of Health (grants 5R01HL70265‐5 and 5P01HL101398‐02)
• Keywords: coronary disease; mental stress; ischemia; vasoconstriction
• Research Categories: Health Sciences, Mental Health; Health Sciences, Public Health

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. Methods and 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. Keywords: coronary disease, ischemia, mental stress, vasoconstriction