Myocardial risk area defined by technetium-99m sestamibi imaging during percutaneous transluminal coronary angioplasty: comparison with coronary angiography.
OBJECTIVE
The purpose of this study was to compare the assessment of myocardial area at risk in patients with coronary artery stenosis by coronary angiography and quantitative myocardial perfusion imaging with technetium-99m sestamibi.


BACKGROUND
Decisions concerning patient management frequently rely on semiquantitative angiographic estimation of the myocardial area at risk, although this approach has not been well validated. Technetium-99m sestamibi is a perfusion imaging agent with little redistribution after initial myocardial uptake. This characteristic allows for injection during angioplasty and later imaging for visualization and quantitation of the nonperfused area at risk.


METHODS
Thirty-nine patients referred for coronary angioplasty were studied. Technetium-99m sestamibi was injected intravenously during angioplasty balloon inflation. Planar (33 patients) or tomographic (6 patients) imaging was performed after completion of angioplasty. Imaging was repeated 24 to 48 h later. Myocardial risk area (perfusion defect on angioplasty image) was quantified as an integral using circumferential count distribution profiles and normal reference. Angiographic risk area was assessed using five scoring methods.


RESULTS
The scintigraphic risk area was 14 +/- 15 on planar images and 39 +/- 16 on tomography. Scintigraphic risk area of patients with infarction was larger than in patients without (22 +/- 17 versus 7 +/- 8, p = 0.003). The left anterior descending coronary artery had a larger mean risk area than other vessels (22 +/- 15 versus 7 +/- 11, p = 0.002). The presence of angiographic collateral channels was associated with smaller risk areas. Angiographic risk scores correlated only moderately with the technetium-99m sestamibi risk area (r = 0.54 to 0.65), with considerable spread of data.


CONCLUSIONS
Area at risk estimated from coronary angiography does not correlate well with that from quantitative myocardial perfusion imaging with technetium-99m sestamibi. These findings emphasize that the functional significance of coronary artery disease is not predicted by coronary anatomy alone.
Haronian
H L
HL
Department of Medicine (Section of Cardiovascular Medicine), Yale University School of Medicine, New Haven, Connecticut 06510.
Remetz
M S
MS
Sinusas
A J
AJ
Baron
J M
JM
Miller
H I
HI
Cleman
M W
MW
Zaret
B L
BL
Wackers
F J
FJ
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015906:Angioplasty, Balloon, Coronary; D002985:Clinical Protocols; D003097:Collateral Circulation; D017023:Coronary Angiography; D003327:Coronary Disease / Q000145:classification / Q000150:complications* / Q000175:diagnosis* / Q000473:pathology / Q000628:therapy; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology / Q000209:etiology* / Q000473:pathology; D015588:Observer Variation; D011237:Predictive Value of Tests; D011379:Prognosis; D015203:Reproducibility of Results; D012307:Risk Factors; D012720:Severity of Illness Index; D017256:Technetium Tc 99m Sestamibi; D015899:Tomography, Emission-Computed, Single-Photon
D017256:Technetium Tc 99m Sestamibi