Unusual CD4+CD28nullT Lymphocytes and Recurrence of Acute Coronary Events

ObjectivesWe hypothesized that the expansion of unusual T lymphocytes, CD4+CD28nullT cells, might represent a key pathogenetic mechanism of recurrent instability.BackgroundClinical presentation of acute coronary syndromes (ACS) is variable. Some patients have recurrent episodes of instability, despite optimal treatment, whereas others have a single acute event in their life. The CD4+CD28nullT cells, with a functional profile that favors vascular injury, have recently been found both in peripheral blood and in unstable coronary plaques of patients with ACS.MethodsPeripheral blood T cells from 120 consecutive unstable angina (UA) patients were analyzed for the distribution of T-cell subsets by flow cytometry. Patients were subgrouped according to the occurrence of prior (during the 24 months before the study enrollment) and subsequent (during the 24 months of follow-up) acute coronary events. For 51 patients, the index event was the first ever (G1); 30 patients had prior events (G2); and 39 patients had further events at follow-up (death, myocardial infarction, or UA) or both before and after the index event (G3).ResultsThe CD4+CD28nullT-cell frequency was higher in G3 than in G2 and G1 (median 9.5% [range 2.4% to 48.0%] vs. 5.1% [range 0.4% to 27.8%] and 2.3% [range 0.2% to 22.8%], respectively; p < 0.001). The expansion of these unusual T lymphocytes was higher in patients with elevated C-reactive protein levels, and it was reduced by statin therapy. On multivariate logistic regression analysis, CD4+CD28nullT-cell frequency was an independent predictor of future acute coronary events (odds ratio 3.01, 95% confidence interval 1.1 to 8.25; p = 0.023).ConclusionsA perturbation of T-cell repertoire is strongly associated with the recurrence of acute coronary events, conceivably playing a key pathogenetic role

Impact of diabetes mellitus on prediction of clinical outcome after coronary revascularization by ¹⁸F-FDG SPECT in patients with ischemic left ventricular dysfunction

Nuclear imaging using 18F-FDG is an established method for the noninvasive assessment of myocardial viability. Data on the value of 18F-FDG imaging in patients with diabetes mellitus are scarce. The aim of this study was to assess whether, in patients with diabetes mellitus and ischemic left ventricular (LV) dysfunction, 18/F-FDG imaging can predict improvement of LV function and heart failure symptoms after coronary revascularization. Methods: A total of 130 consecutive patients with ischemic LV dysfunction who were already scheduled for surgical revascularization were studied; 34 of the patients had diabetes mellitus. All patients underwent radionuclide ventriculography to assess left ventricular ejection fraction (LVEF), resting 2-dimensional echocardiography to identify dysfunctional myocardial tissue, and dual-isotope 18F-FDG/99m/Tc- tetrofosmin SPECT after oral administration of acipimox. Nine to 12 mo after coronary revascularization, radionuclide ventriculography and echocardiography were repeated. An improvement in LVEF by at least5% was considered significant. Results: 18F-FDG SPECT demonstrated that 610 (50%) of 1,212 dysfunctional segments were viable. Patients with and without diabetes mellitus had a comparable number of dysfunctional but viable segments per patient. Also, the number of patients with a substantial amount of dysfunctional but viable myocardium (≥ viable segments) was comparable between the groups with and without diabetes mellitus. The presence of substantial viability on 18F-FDG SPECT was predictive of improvement in LVEF and heart failure symptoms postoperatively (sensitivity and specificity of 82% and 89%, respectively, in patients with diabetes and 83% and 93%, respectively, in patients without diabetes; not statistically significant). Conclusion: 18F-FDG SPECT is practical for routine assessment of myocardial viability in patients with ischemic LV dysfunction with or without diabetes mellitus. Patients with substantial myocardial viability on 18F-FDG SPECT have a high probability of improvement of LV function and symptoms after coronary revascularization, irrespective of the absence or presence of diabetes mellitus.</p

Impact of diabetes mellitus on prediction of clinical outcome after coronary revascularization by ¹⁸F-FDG SPECT in patients with ischemic left ventricular dysfunction

Nuclear imaging using 18F-FDG is an established method for the noninvasive assessment of myocardial viability. Data on the value of 18F-FDG imaging in patients with diabetes mellitus are scarce. The aim of this study was to assess whether, in patients with diabetes mellitus and ischemic left ventricular (LV) dysfunction, 18/F-FDG imaging can predict improvement of LV function and heart failure symptoms after coronary revascularization. Methods: A total of 130 consecutive patients with ischemic LV dysfunction who were already scheduled for surgical revascularization were studied; 34 of the patients had diabetes mellitus. All patients underwent radionuclide ventriculography to assess left ventricular ejection fraction (LVEF), resting 2-dimensional echocardiography to identify dysfunctional myocardial tissue, and dual-isotope 18F-FDG/99m/Tc- tetrofosmin SPECT after oral administration of acipimox. Nine to 12 mo after coronary revascularization, radionuclide ventriculography and echocardiography were repeated. An improvement in LVEF by at least5% was considered significant. Results: 18F-FDG SPECT demonstrated that 610 (50%) of 1,212 dysfunctional segments were viable. Patients with and without diabetes mellitus had a comparable number of dysfunctional but viable segments per patient. Also, the number of patients with a substantial amount of dysfunctional but viable myocardium (≥ viable segments) was comparable between the groups with and without diabetes mellitus. The presence of substantial viability on 18F-FDG SPECT was predictive of improvement in LVEF and heart failure symptoms postoperatively (sensitivity and specificity of 82% and 89%, respectively, in patients with diabetes and 83% and 93%, respectively, in patients without diabetes; not statistically significant). Conclusion: 18F-FDG SPECT is practical for routine assessment of myocardial viability in patients with ischemic LV dysfunction with or without diabetes mellitus. Patients with substantial myocardial viability on 18F-FDG SPECT have a high probability of improvement of LV function and symptoms after coronary revascularization, irrespective of the absence or presence of diabetes mellitus.</p

Why do patients with ischemic cardiomyopathy and a substantial amount of viable myocardium not always recover in function after revascularization?

In patients with ischemic cardiomyopathy and a substantial amount of dysfunctional but viable myocardium, myocardial revascularization may improve left ventricular ejection fraction. The aim of this study was to evaluate why not all patients with a substantial amount of viable tissue recover in function after revascularization