The prognosis for prognosis remains excellent

Abstract

Do we really need another paper on prognosis? The topic has been explored exhaustively. We have seen studies identifying the ability of myocardial perfusion imaging (MPI) to stratify prognosis with planar imaging and SPECT, thallium, sestamibi, tetrofosmin, dual isotope, and rubidium. [1][2][3][4][5][6][7][8][9][10][11] We have heard about prognosis using treadmill exercise and pharmacologic stress using dipyridamole, adenosine, and dobutamine. 5,10,[12][13][14][15] We have read studies looking at men, women, metabolic syndrome, obesity, diabetics, and patients with endstage renal disease. 5,[16][17][18][19][20] The literature is peppered with studies looking at low and intermediate Duke treadmill scores, patients with LBBB, left ventricular hypertrophy, and normal EKGs. 12,[21][22][23] There are papers looking at patients with suspected coronary disease, catheterization documented coronary disease, stable angina, and post infarction patients. 10,13,24,25 When it seems that the list is complete, when every conceivable subgroup has been identified and studied, Doukky et al 26 have managed to identify yet another group: MPI in an outpatient primary care setting. As a group, this referral population would be expected to have less acuity and presumably a better prognosis, but as this group is more reflective of the general population it certainly merits careful scrutiny.They identified a consecutive series of 1,546 patients of whom greater than 1400 met entry criteria; a mean follow-up of 27 months was obtained in 99%. The majority of the scans were normal, only 12.5% were deemed abnormal due to perfusion defects, decreased function or both. Not surprisingly, the overall cardiac event rates were both hard events (mortality and myocardial infarction) and revascularization were low. Cox analysis once again showed that an abnormal MPI was a strong predictor of cardiac events while the overall event rates in patients with normal scans was quite low (0.54% death or MI) somewhat lower than the approximately 1% rate reported in cardiologist-based practices. The summed stress score, as in previous studies, showed a stepwise influence on prognosis.The study was performed using only a single blinded reader using semi-quantitative analysis with commercially available software. It should be noted that the authors used a SSS of C1 as abnormal, a deviation from most of the published literature. This is unlikely to effect the conclusions as the most important finding is the correlation between SSS and outcome and not where the line between normal and abnormal is drawn.This study raises important questions about appropriateness. This includes not just whether the indication for the test was appropriate but also the appropriate follow-up of abnormal tests and the appropriateness of the appropriate use criteria themselves. The authors report that nearly half the studies ordered were classified as inappropriate under the current AUC criteria. It is noted that AUC criteria were not as widely recognized during the time the study was con...

Prediction Models for Cardiac Risk Classification with Nuclear Cardiology Techniques

“…Documented changes in the clinical manifestations and treatment of coronary artery disease are challenging the role of cardiac radionuclide imaging for prognostication. Nevertheless, recent reviews [26,27] and meta-analysis [28•] have well described the abundance of evidence published on the prognostic accuracy of stress myocardial perfusion imaging and Bthe prognosis for prognosis remains excellent^ [29]. This review, rather than focus on individual studies, will analyze some specific aspects related to prediction model building and validation.…”

Studies of vertex tracking with SOI pixel sensors for future lepton colliders

“…Vertex tracking is one of the capabilities most crucial to a detector at future lepton colliders and flavour factories. Much of the anticipated physics program at a high energy lepton collider, such as the ILC, CLIC or a muon collider relies on the ability of efficiently discriminating heavy (t, b, c and τ ) from light fermions [1,2]. If the Higgs boson exists at a mass of ≃ 125 GeV, as possibly indicated by the recent preliminary LHC [3,4] and Tevatron [5] results, the precise determination of its couplings to fermions will be essential to test whether the Brout-Englert-Higgs mechanism of electro-weak symmetry breaking is also responsible for fermion mass generation.…”

Have SPECT artifacts breathed their last?

“…That is, the highest risk patients should still be correctly identified and the prognostic power of MPI (which is its most clinically useful feature) remains intact. 12 This is not to neglect the importance of diagnostic accuracy; we should continue to pursue all avenues that might improve this. It is helpful that the artifacts encountered are usually mild and appear to be atypical for coronary distributions.…”