Author + information
- Received April 24, 1993
- Revision received November 4, 1993
- Accepted November 9, 1993
- Published online March 15, 1994.
- Marcelo Di Carli, MDa,b,
- Todd Sherman, MD, FACCa,b,
- Sandeep Khanna, MDa,b,
- Michael Davidson, BSa,b,
- Soleyman Rokhsar, BSa,b,
- Randall Hawkins, MD, PhDa,b,
- Michael Phelps, PhDa,b,
- Heinrich Schelbert, MD, FACCa,b and
- Jamshid Maddahi, MD, FACC∗,a,b
- ↵∗Address for correspondence: Dr. Jamshid Maddahi, Division of Nuctear Medicine, University of California, Los Angeles School of Medicine, CHS AR-175,10833 Le Conte Avenue. Los Angeles, California 90024-1721.
Objectives. This study aimed to determine whether angiographically visualized collateral vessels in patients with chronic coronary artery disease imply the presence of viable myocardium in asynergic regions subtended by completely occluded coronary arteries.
Background. Patients with chronic coronary artery disease who are being considered for revascularization frequently exhibit angiographically visualized collateral vessels to completely occluded coronary arteries supplying seventy asynergic myocardial regions. However, little is known about the relation between angiographic collateral flow and myocardial viability in these patients.
Methods. We studied 42 patients with 78 completely occluded coronary arteries supplying asynergic territories. Angiographic collateral vessels were interpreted as absent (grade 1) in 14 patients, minimal (grade 2) in 27 and well developed (grade 3) in 37. Myocardial viability was determined with positron emission tomography using nitrogen-13 (N-13) ammonia and fluorine-18 (F-18) deoxyglucose lor assessment of regional perfusion and glucose uptake, respectively. Positron emission tomographic patterns were interpreted as mismatch (perfusion defect with enhanced F-18 deoxyghicose uptake); transmural match (severe concordant reduction or absence of both perfusion and F-18 deoxyglucose uptake) or nontransmural match (mild to moderate concordant reduction of both perfusion and F-18 deoxyglucose uptake).
Results. There was no significant correlation (p = 0.14) between the severity of perfusion deficit assessed by positron emission tomography and the collateral grade. The extent of mismatch was unrelated to either the presence or the magnitude of collateral vessels. Conversely, with increasing collateral vessels from grade 1 to 3, the total extent of positron emission tomographic match remained similar, whereas the ratio of transmural to nontransmural match decreased. Myocardial viability was usually present in severely hypokinetic regions (82%). It was lower in akinetic-dyskinetic regions (49%). Of the 64 regions with angiographic collateral vessels, 37 (58%) (95% confidence interval [CI]46% to 70%) showed positron emission tomographic mismatch. In contrast, 7 (50%) of 14 (95% CI 24% to 76%) regions without collateral vessels on angiography exhibited positron emission tomographic mismatch. The presence of angtographically visualized collateral vessels was a sensitive (84%) but not specific (21%) marker of viability.
Conclusions. In patients with chronic coronary artery disease, angtographically visualized collateral vessels to asynergc myocardial regions subtended by occluded coronary arteries do not always imply the presence of viable myocardium, suggesting that revascularization may not always provide a functional benefit.
☆ This study was supported in part by the Director of the Office of Energy Research, Office of Health and Environmental Research, Washington, D.C. and Research Grant HL-29845, National Heart. Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland. This work was completed during Dr. DiCarli's tenure as a Research Fellow of the American Heart Association, Greater Los Angeles Affiliate, Los Angeles, California.
- Received April 24, 1993.
- Revision received November 4, 1993.
- Accepted November 9, 1993.