Prevalence of symptomatic and silent stress-induced perfusion defects in diabetic patients with suspected coronary artery disease referred for myocardial perfusion scintigraphy.
OBJECTIVE
Silent myocardial ischaemia--as evaluated by stress-induced perfusion defects on myocardial perfusion scintigraphy (MPS) in patients without a history of chest pain--is frequent in diabetes and is associated with increased rates of cardiovascular events. Its prevalence has been determined in asymptomatic diabetic patients, but remains largely unknown in diabetic patients with suspected coronary artery disease (CAD) in the clinical setting. In this study we therefore sought (a) to determine the prevalence of symptomatic and silent perfusion defects in diabetic patients with suspected CAD and (b) to characterise the eventual predictors of abnormal perfusion.


METHODS
The patient population comprised 133 consecutive diabetic patients with suspected CAD who had been referred for MPS. Studies were performed with exercise (41%) or pharmacological stress testing (1-day protocol, (99m)Tc-sestamibi, 201Tl or both). We used semi-quantitative analysis (20-segment polar maps) to derive the summed stress score (SSS) and the summed difference score (SDS).


RESULTS
Abnormal MPS (SSS> or =4) was observed in 49 (37%) patients (SSS=4.9+/-8.4, SDS=2.4+/-4.7), reversible perfusion defects (SDS> or =2) in 40 (30%) patients [SSS=13.3+/-10.9; SDS=8.0+/-5.6; 20% moderate to severe (SDS>4), 7% multivessel] and fixed defects in 21 (16%) patients. Results were comparable between patients with and patients without a history of chest pain. Of 75 patients without a history of chest pain, 23 (31%, 95% CI=21-42%) presented reversible defects (SSS=13.9+/-11.3; SDS=7.4+/-1.2), indicative of silent ischaemia. Reversible defects were associated with inducible ST segment depression during MPS stress [odds ratio (OR)=3.2, p<0.01). Fixed defects were associated with erectile dysfunction in males (OR=3.7, p=0.02) and lower aspirin use (OR=0.25, p=0.02).


CONCLUSIONS
Silent stress-induced perfusion defects occurred in 31% of the patients, a rate similar to that in patients with a history of chest pain. MPS could identify these patients with a potentially increased risk of cardiovascular events.
Prior
John O
JO
Division of Nuclear Medicine, Centre Hospitalier Universitaire Vaudois (CHUV University Hospital), 1011, Lausanne, Switzerland. john.prior@chuv.hospvd.ch
Monbaron
David
D
Koehli
Melanie
M
Calcagni
Maria-Lucia
ML
Ruiz
Juan
J
Bischof Delaloye
Angelika
A
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015984:Causality; D015897:Comorbidity; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D003920:Diabetes Mellitus / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D005080:Exercise Test; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D015995:Prevalence; D011379:Prognosis; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D012680:Sensitivity and Specificity; D013557:Switzerland / Q000453:epidemiology; D017256:Technetium Tc 99m Sestamibi
D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi