Assessing the Prevalence and Predicting Factors of an Abnormal Gated
Myocardial Perfusion SPECT in Asymptomatic Patients with Type 2 Diabetes
Abstract
Abstract Introduction: Considering the significant prevalence of silent
myocardial ischemia and its related morbidity and mortality in
asymptomatic type two diabetic patients, it is not well known whether
early screening with MPI is cost-effective. However, predicting factors
are not elucidated. Materials and Methods: This was a cross-sectional
study including 63 asymptomatic patients with type 2 diabetes mellitus
(T2DM), with normal ECG and ejection fraction. Patients with any history
of documented valvular, congestive or ischemic heart disease, renal or
hepatic failure were excluded. At first all patients were interviewed
and checked for risk factors and then patients underwent a two-day
rest/stress 99mTc-MIBI gated MPI SPECT. Data was assessed by QPS/QGS and
4DM software and evaluated by a nuclear medicine specialist with summed
stress score (SSS) of more than 4 defined as CAD. Results: There were 42
females (67%) and 21 males (33%), with a mean age of 61.33 ± 6.98
years and 7.97 ± 4.86 years history of T2DM. CAD was detected in 26
(41.3%) patients and was significantly associated with male gender,
smoking, requiring insulin therapy and EF (P-value = 0.019, 0.046, 0.05,
0.033, respectively). A significant association was found between the
duration of diabetes, especially when >15y, and the
probability of having CAD.. Multivariable logistic regression revealed
that smoking; male gender and diabetes duration were the strongest
independent predictors of abnormal MPI results. Conclusion: We found a
high (46%) prevalence of abnormal stress MPI SPECT in patients with
type 2 diabetes mellitus, despite being asymptomatic. Asymptomatic
patients with a history of smoking, long duration of diabetes, being
under insulin treatment and male gender might benefit from MPI for early
detection of silent ischemia. Keyword: 99mTc-MIBI; Gated Myocardial
Perfusion Imaging; Type 2 Diabetes Mellitus; Silent Ischemia;
Asymptomatic CAD; Early Screening