Author + information
- Received October 18, 2007
- Revision received December 5, 2007
- Accepted December 8, 2007
- Published online March 1, 2008.
- Masahiro Terashima, MD, PhD, FACC⁎,
- Patricia K. Nguyen, MD⁎,
- Geoffrey D. Rubin, MD†,
- Carlos Iribarren, MD, MPH, PhD§,
- Brian K. Courtney, MD⁎,
- Alan S. Go, MD§∥,
- Stephen P. Fortmann, MD‡ and
- Michael V. McConnell, MD, MSEE, FACC⁎,⁎ ()
Reprint requests and correspondence:
Dr. Michael V. McConnell, Division of Cardiovascular Medicine, Stanford University School of Medicine, 300 Pasteur Drive, Room H-2157, Stanford, California 94305-5233.
Objectives This study evaluated the hypothesis that impaired nitroglycerin (NTG)-induced coronary vasodilation is associated with advanced coronary atherosclerosis in asymptomatic older patients.
Background Atherosclerosis is associated with both structural and functional abnormalities of the vessel wall. Noninvasive functional measures of subclinical coronary atherosclerosis may help characterize high-risk subjects and guide preventive therapy.
Methods A total of 236 older patients (age 60 to 72 years, 33% female) without a history of cardiovascular disease were studied. Nitroglycerin-induced coronary vasodilation was measured by magnetic resonance angiography (MRA). Cross-sectional images of the right coronary artery were acquired before and 5 min after 0.4-mg sublingual NTG using a gated, breath-held spiral coronary MRA sequence (0.7-mm resolution). Quantitative analysis of the increase in cross-sectional area was performed in the 90% of patients (n = 212) with adequate image quality. Quantitation of coronary artery calcification (CAC) was performed by multidetector computed tomography using the Agatston method.
Results Forty patients (19%) had advanced CAC (≥400). Coronary vasodilation to NTG was significantly impaired (p = 0.02) in patients with advanced CAC (median [interquartile range] = 15.9% [4.2% to 28.0%] vs. 21.5% [9.6% to 36.6%] for CAC <400). Importantly, NTG-induced coronary vasodilation remained independently associated with advanced CAC after multivariate analysis incorporating risk factors (p = 0.02) and other potential confounders (p = 0.04). There was no significant difference in coronary vasodilation between men and women, but few women (n = 3) had advanced CAC.
Conclusions Impaired NTG-induced coronary vasodilation by MRA is associated with advanced coronary atherosclerosis in a community-based cohort of older asymptomatic subjects. Coronary MRA may provide a noninvasive functional assessment of subclinical coronary atherosclerosis.
This study was supported by grants from the Donald W. Reynolds Foundation (Las Vegas, Nevada); National Heart, Lung, and Blood Institute (grant R01HL39297, Bethesda, Maryland); and General Electric Healthcare (Waukesha, Wisconsin). Dr. Rubin is a consultant/advisory board member for TeraRecon, Inc., and Siemens Medical Solutions. Dr. McConnell receives research support from GE Healthcare, is on a scientific advisory board for Kowa, Inc., and has been an advisor for Philips Medical Systems.
- Received October 18, 2007.
- Revision received December 5, 2007.
- Accepted December 8, 2007.
- American College of Cardiology Foundation