Author + information
- Received June 23, 2010
- Revision received October 29, 2010
- Accepted November 9, 2010
- Published online February 1, 2011.
- Shanmugam Uthamalingam, MD⁎,
- Hui Zheng, PhD†,
- Marcia Leavitt, BA⁎,
- Eugene Pomerantsev, MD, PhD⁎,
- Imad Ahmado, MD⁎,
- Gagandeep S. Gurm, MD⁎ and
- Henry Gewirtz, MD⁎,⁎ ()
- ↵⁎Reprint requests and correspondence:
Dr. Henry Gewirtz, Cardiac Unit/Yawkey 5E, Massachusetts General Hospital, Boston, Massachusetts 02114
Objectives The authors tested the hypothesis that exercise treadmill testing (ETT)–induced ST-segment elevation (STE) in electrocardiographic lead aVR is an important indicator of significant left main coronary artery (LMCA) or ostial left anterior descending coronary artery (LAD) stenosis.
Background Although STE in lead aVR is an indicator of LMCA or very proximal LAD occlusion in acute coronary syndromes, its predictive power in the setting of ETT is uncertain.
Methods Rest and stress electrocardiograms, clinical and stress test parameters, and single photon-emission computed tomographic myocardial perfusion imaging (MPI) data, when available, were obtained in 454 subjects (378 with MPI) who underwent cardiac catheterization and standard Bruce ETT ≤ 6 months before catheterization. Patients were selected for LMCA or ostial LAD disease (≥50% stenosis) with or without other coronary artery disease (CAD), CAD (≥70% stenosis) without significant LMCA or ostial LAD, or no significant CAD. Univariate followed by multivariate logistic regression analyses of clinical, electrocardiographic, stress test, and single photon-emission computed tomographic MPI variables were used to identify significant correlates of LMCA or ostial LAD stenosis. Bayesian analysis of the data also was performed.
Results LMCA (n = 38) or ostial LAD (n = 42) stenosis occurred in 75 patients (5 patients had both). The remainder had CAD without LMCA or ostial LAD stenosis (n = 276) or no CAD (n = 103). In multivariate analysis, the strongest predictor was stress-induced STE in lead aVR (p < 0.0001, area under the curve 0.82). Both left ventricular ejection fraction (after stress) and percent reversible LAD ischemia on single photon-emission computed tomographic MPI also contributed significantly in multivariate analysis (p < 0.005 and p < 0.05, respectively, areas under the curve 0.60 and 0.64, respectively). Although additional electrocardiographic, stress test, and MPI variables were significant univariate predictors, none was statistically significant in multivariate analysis. At 1-mm STE in lead aVR, sensitivity for LMCA or ostial LAD stenosis was 75%, specificity was 81%, overall predictive accuracy was 80%, and post-test probability increased nearly 3 times from 17% to 45%.
Conclusions Stress (ETT)–induced STE in lead aVR is an important indicator of significant LMCA or ostial LAD stenosis and should not be ignored.
This work was conducted with support from Harvard Catalyst The Harvard Clinical and Translational Science Center (National Institutes of Health award UL1 RR 025758 and financial contributions from Harvard University and its affiliated academic health care centers). The content is solely the responsibility of the authors and does not necessarily represent the official views of Harvard Catalyst, Harvard University and its affiliated academic health care centers, the National Center for Research Resources, or the National Institutes of Health. Dr. Gewirtz has received a research grant from FluoroPharma unrelated to this topic. All other authors have reported that they have no relationships to disclose.
- Received June 23, 2010.
- Revision received October 29, 2010.
- Accepted November 9, 2010.
- American College of Cardiology Foundation