Author + information
- Received March 30, 2006
- Revision received July 5, 2006
- Accepted July 6, 2006
- Published online December 19, 2006.
- John J. Mahmarian, MD, FACC⁎,1,⁎ (, )
- Leslee J. Shaw, PhD†,2,
- Neil G. Filipchuk, MD‡,3,
- Habib A. Dakik, MD§,
- Sherif S. Iskander, MD∥,4,
- Terrence D. Ruddy, MD¶,
- Milena J. Henzlova, MD#,4,
- Felix Keng, MD⁎⁎,
- Adel Allam, MD††,
- Lemuel A. Moyé, MD, PhD‡‡,
- Craig M. Pratt, MD, FACC⁎,
- INSPIRE Investigators
- ↵⁎Reprint requests and correspondence:
Dr. John J. Mahmarian, Department of Cardiology, Methodist DeBakey Heart Center, 6550 Fannin Street, SM-677, Houston, Texas 77030.
Objectives The purpose of this study was to determine whether gated adenosine Tc-99m sestamibi single-photon emission computed tomography (ADSPECT) could accurately define risk and thereby guide therapeutic decision making in stable survivors of acute myocardial infarction (AMI).
Background Controversy continues as to the role of noninvasive stress imaging in stratifying risk early after AMI.
Methods The INSPIRE (Adenosine Sestamibi Post-Infarction Evaluation) trial is a prospective multicenter trial which enrolled 728 clinically stable survivors of AMI who had gated ADSPECT within 10 days of hospital admission and subsequent 1-year follow-up. Event rates were assessed within prospectively defined INSPIRE risk groups based on the adenosine-induced left ventricular perfusion defect size, extent of ischemia, and ejection fraction.
Results Total cardiac events/death and reinfarction significantly increased within each INSPIRE risk group from low (5.4%, 1.8%), to intermediate (14%, 9.2%), to high (18.6%, 11.6%) (p < 0.01). Event rates at 1 year were lowest in patients with the smallest perfusion defects but progressively increased when defect size exceeded 20% (p < 0.0001). The perfusion results significantly improved risk stratification beyond that provided by clinical and ejection fraction variables. The low-risk INSPIRE group, comprising one-third of all enrolled patients, had a shorter hospital stay with lower associated costs compared with the higher-risk groups (p < 0.001).
Conclusions Gated ADSPECT performed early after AMI can accurately identify a sizeable low-risk group who have a <2% death and reinfarction rate at 1 year. Identifying these low-risk patients for early hospital discharge may improve utilization of health care resources at considerable cost savings.
↵1 Dr. Mahmarian is on the Advisory Board for CV Therapeutics and Astellas Pharma US.
↵2 Dr. Shaw has received research grants for the END and COURAGE trials
↵3 Dr. Filipchuk received research grants for the DIAD, CCORD, and AMISCAN studies
↵4 Drs. Iskander and Henzlova are on the Speakers’ Bureau for Bristol-Myers Squibb.
Funding for INSPIRE was provided by Bristol-Myers Squibb Medical Imaging, Astellas Pharma US, and Schering Plough Research Institute.
- Received March 30, 2006.
- Revision received July 5, 2006.
- Accepted July 6, 2006.
- American College of Cardiology Foundation