Ethnic differences in the prognostic value of stress technetium-99m tetrofosmin gated single-photon emission computed tomography myocardial perfusion imaging.
OBJECTIVE
This study was designed to evaluate the differential prognostic value of gated single-photon emission computed tomographic imaging (SPECT) imaging in an ethnically diverse multicenter registry.


BACKGROUND
Ethnic minority patient populations have reportedly higher coronary heart disease mortality with greater comorbidity and a clustering of risk factors at a significantly younger age when compared with Caucasian, non-Hispanic patients. Despite our increasingly diverse population, the predictive accuracy of cardiac imaging in ethnic minority patients is ill-defined.


METHODS
A total of 7,849 patients were prospectively enrolled in a registry of patients undergoing exercise (44%) or pharmacologic stress (56%) technetium-99m tetrofosmin SPECT. Scans were scored using a 20-segment myocardial model with a 5-point severity index. Multivariable Cox proportional hazards models were employed to assess time to death or myocardial infarction.


RESULTS
A total of 1,993 African-American, 464 Hispanic, and 5,258 Caucasian non-Hispanic patients underwent SPECT imaging. African-American and Hispanic patients more often had a history of stroke, peripheral arterial disease, angina, heart failure, diabetes, hypertension, and smoking at a younger age. Moderate or severely abnormal SPECT scans were noted in 21%, 17%, and 13% of African-American, Hispanic, and Caucasian non-Hispanic patients, respectively (p < 0.0001). Cardiovascular death rates were highest for ethnic minority patients (p < 0.0001). Annual rates of ischemic heart disease death ranged from 0.2% to 3.0% for Caucasian non-Hispanic and 0.8% to 6.5% for African-American patients with low-risk to severely abnormal SPECT scans (p < 0.0001). For post-stress ejection fraction <45%, annualized risk-adjusted death rates were 2.7% for Caucasian non-Hispanic patients versus 8.0% and 14.0% for African-American and Hispanic patients (p < 0.0001).


CONCLUSIONS
The current results from a large observational registry reveal that exercise and pharmacologic stress SPECT effectively predicts major cardiovascular events in a large cohort of African-American and Hispanic patients evaluated for suspected myocardial ischemia. These results provide further evidence that ethnic minority patient populations have a worsening outcome related to cardiovascular disease.
Shaw
Leslee J
LJ
Cedars-Sinai Medical Center, Los Angeles, California 90048, USA. shaw@cshs.org
Hendel
Robert C
RC
Cerquiera
Manuel
M
Mieres
Jennifer H
JH
Alazraki
Naomi
N
Krawczynska
Elizabeth
E
Borges-Neto
Salvador
S
Maddahi
Jamshid
J
Bairey Merz
C Noel
CN
D001741:Black or African American / Q000706:statistics & numerical data; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000208:ethnology* / Q000401:mortality / Q000473:pathology; D018572:Disease-Free Survival; D005080:Exercise Test; D005260:Female; D006630:Hispanic or Latino / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D019275:Radiopharmaceuticals; D012042:Registries; D012720:Severity of Illness Index; D016019:Survival Analysis; D017256:Technetium Tc 99m Sestamibi; D015899:Tomography, Emission-Computed, Single-Photon; D014481:United States / Q000453:epidemiology; D044465:White People / Q000706:statistics & numerical data
D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi