Transient Ischemic Dilation in Patients With Diabetes Mellitus

Abstract

Background-We prospectively evaluated the incremental prognostic value of transient ischemic dilation (TID) in patients with type 2 diabetes mellitus during long-term follow-up and estimated cardiac death and nonfatal myocardial infarction (MI) using traditional approaches of prognostication to more recent methods. Methods and Results-A total of 672 consecutive diabetic patients with available rest and stress gated myocardial perfusion single-photon emission computed tomographic data were enrolled. Stepwise Cox regression analysis was used to estimate cardiac death or nonfatal MI. Risk reclassification was calculated, and an exploratory analysis was performed to evaluate the effect of coronary revascularization on event-free survival. Adding TID to a multivariable model, including age, history of MI, stress type, poststress left ventricular ejection fraction, and stress-induced myocardial ischemia, improved discrimination of cardiac death or nonfatal MI (C statistic, 0.74-0.82; P=0.01; adjusted hazard ratio, 3.6; P<0.0001) and led to a net reclassification improvement of 0.39 (95% confidence interval, 0.14-0.64). Revascularization had a significant effect on event-free survival (adjusted hazard ratio, 0.25; P<0.001), with significant interactions between revascularization and poststress left ventricular ejection fraction, revascularization and stress-induced myocardial ischemia, and revascularization and TID (all P<0.01) Conclusions-TID provides independent and incremental prognostic information for the prediction of cardiac death or nonfatal MI in patients with diabetes mellitus. The addition of TID to a prediction model based on cardiovascular risk factors, left ventricular ejection fraction, and ischemia significantly improves risk discrimination and reclassification for incident cardiac events. The effect of revascularization seems to be influenced by left ventricular systolic function, stressinduced myocardial ischemia, and TID. (Circ Cardiovasc Imaging. 2013;6:908-915.)

Immortality time and serial myocardial perfusion imaging: Only those who do not die may repeat the exam

“…Transient ischemic LV cavity dilation is another high-risk variable associated with the presence of severe angiographic CAD 5 and with an adverse outcome. 6,7 Serial MPI imaging has been used to compare the effectiveness of intercurrent treatments, within the framework of randomized controlled trials. [8][9][10] Moreover, an analysis of the Detection of Ischemia in Asymptomatic Diabetics (DIAD) study not including patients with intervening cardiac events or revascularization found unexpected resolution of ischemia in most of these patients, potentially because of more aggressive medical treatment of cardiovascular risk factors.…”

Cardiovascular risk stratification in diabetic patients: Is all in METS?

“…13 Net reclassification improvement (NRI) has been adopted in diabetic patients with suspected or known CAD to evaluate the extent to which adding MPS imaging findings to a model based on traditional risk factors and ECG stress test data correctly reclassifies the risk of severe CAD and of subsequent cardiac events during a long-term follow-up. 6,[14][15][16][17] In the Impact of Inducible Ischemia by Stress SPECT (IDIS) trial, risk estimates for a coronary heart disease event were categorized in 822 consecutive diabetic patients as 0% to \3%, 3% to \5%, and C5% per year using two Cox proportional hazards models. 16,17 Model 1 used traditional coronary heart disease risk factors and ECG stress test data and model 2 used these variables plus MPS imaging data.…”

Real-time gated-SPECT myocardial perfusion imaging with CZT detectors: A promising tool for monitoring left ventricular function

“…This parameter reflects a combination of LV dilation and diffused subendocardial ischemia and provides incremental diagnostic and prognostic information to standard perfusion analysis in patients with known or suspected CAD. 23,24 Although obtained in a limited number of patients, the results reported by Nkoulou et al 16 are very interesting and open the way for wider applications of SPECT imaging. Additional and larger studies are clearly needed to assess the clinical applicability of the proposed approach.…”