Expedited review
Relationship between stress-induced myocardial ischemia and atherosclerosis measured by coronary calcium tomography

https://doi.org/10.1016/j.jacc.2004.06.042Get rights and content
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Objectives

We assessed the relationship between stress-induced myocardial ischemia on myocardial perfusion single-photon emission computed tomography (MPS) and magnitude of coronary artery calcification (CAC) by X-ray tomography in patients undergoing both tests.

Background

There has been little evaluation regarding the relationship between CAC and inducible ischemia or parameters that might modify this relationship.

Methods

A total of 1,195 patients without known coronary disease, 51% asymptomatic, underwent stress MPS and CAC tomography within 7.2 ± 44.8 days. The frequency of ischemia by MPS was compared to the magnitude of CAC abnormality.

Results

Among 76 patients with ischemic MPS, the CAC scores were >0 in 95%, ≥100 in 88%, and ≥400 in 68%. Of 1,119 normal MPS patients, CAC scores were >0, ≥100, and ≥400 in 78%, 56%, and 31%, respectively. The frequency of ischemic MPS was <2% with CAC scores <100 and increased progressively with CAC ≥100 (p for trend <0.0001). Patients with symptoms with CAC scores ≥400 had increased likelihood of MPS ischemia versus those without symptoms (p = 0.025). Absolute rather than percentile CAC score was the most potent predictor of MPS ischemia by multivariable analysis. Importantly, 56% of patients with normal MPS had CAC scores ≥100.

Conclusions

Ischemic MPS is associated with a high likelihood of subclinical atherosclerosis by CAC, but is rarely seen for CAC scores <100. In most patients, low CAC scores appear to obviate the need for subsequent noninvasive testing. Normal MPS patients, however, frequently have extensive atherosclerosis by CAC criteria. These findings imply a potential role for applying CAC screening afterMPS among patients manifesting normal MPS.

Abbreviations and acronyms

CAC
coronary artery calcium
CAD
coronary artery disease
CT
computed tomography
EBCT
electron beam computed tomography
HU
Hounsfield units
MPS
myocardial perfusion single-photon emission computed tomography
MSCT
multislice spiral computed tomography
SDS
summed difference score
SPECT
single-photon emission computed tomography
SRS
summed rest score
SSS
summed stress score
Tc
technetium
Tl
thallium

Cited by (0)

This study was supported by a grant from the Eisner Foundation, Los Angeles, California. Dr. John J. Mahamarian acted as Guest Editor for this paper.