Background: The various plaque components have been associated with ischemia and outcomes in patients with coronary artery disease (CAD). The main goal of this analysis was to test the hypothesis... Show moreBackground: The various plaque components have been associated with ischemia and outcomes in patients with coronary artery disease (CAD). The main goal of this analysis was to test the hypothesis that, at patient level, the fraction of non-calcified plaque volume (PV) of total PV is associated with ischemia and outcomes in patients with CAD. This ratio could be a simple and clinically useful parameter, if predicting outcomes. Methods: Consecutive patients with suspected CAD undergoing coronary computed tomography angiography with selective positron emission tomography perfusion imaging were selected. Plaque components were quantitatively analyzed at patient level. The fraction of various plaque components were expressed as percentage of total PV and examined among patients with non-obstructive CAD, suspected stenosis with normal perfusion, and those with reduced myocardial perfusion. Clinical outcomes included all-cause mortality and myocardial infarction. Results: In total, 494 patients (age 63 & PLUSMN; 9 years, 55% male) were included. Total PV and all plaque components were significantly larger in patients with reduced myocardial perfusion compared to patients with normal perfusion and those with non-obstructive CAD. During follow-up 35 events occurred. Patients with any plaque component & GE; median showed worse outcomes (log-rank p < 0.001 for all). In addition, low-attenuation plaque & GE; median was associated with worse outcomes independent of total PV (adjusted HR: 2.754, 95% CI: 1.022-7.0419, p = 0.045). The fractions of the various plaque components were not associated with outcomes. Conclusion: Larger total PV or any plaque component at patient level are associated with abnormal myocardial perfusion and adverse events. The various plaque components as fraction of total PV lack additional prognostic value. Show less
Schultz, J.; Hoogen, I.J. van den; Kuneman, J.H.; Graaf, M.A. de; Kamperidis, V.; Broersen, A.; ... ; Knuuti, J. 2022
Endothelial wall shear stress (ESS) is a biomechanical force which plays a role in the formation and evolution of atherosclerotic lesions. The purpose of this study is to evaluate coronary computed... Show moreEndothelial wall shear stress (ESS) is a biomechanical force which plays a role in the formation and evolution of atherosclerotic lesions. The purpose of this study is to evaluate coronary computed tomography angiography (CCTA)-based ESS in coronary arteries without atherosclerosis, and to assess factors affecting ESS values. CCTA images from patients with suspected coronary artery disease were analyzed to identify coronary arteries without atherosclerosis. Minimal and maximal ESS values were calculated for 3-mm segments. Factors potentially affecting ESS values were examined, including sex, lumen diameter and distance from the ostium. Segments were categorized according to lumen diameter tertiles into small (< 2.6 mm), intermediate (2.6-3.2 mm) or large (>= 3.2 mm) segments. A total of 349 normal vessels from 168 patients (mean age 59 +/- 9 years, 39% men) were included. ESS was highest in the left anterior descending artery compared to the left circumflex artery and right coronary artery (minimal ESS 2.3 Pa vs. 1.9 Pa vs. 1.6 Pa, p < 0.001 and maximal ESS 3.7 Pa vs. 3.0 Pa vs. 2.5 Pa, p < 0.001). Men had lower ESS values than women, also after adjusting for lumen diameter (p < 0.001). ESS values were highest in small segments compared to intermediate or large segments (minimal ESS 3.8 Pa vs. 1.7 Pa vs. 1.2 Pa, p < 0.001 and maximal ESS 6.0 Pa vs. 2.6 Pa vs. 2.0 Pa, p < 0.001). A weak to strong correlation was found between ESS and distance from the ostium (rho = 0.22-0.62, p < 0.001). CCTA-based ESS values increase rapidly and become widely scattered with decreasing lumen diameter. This needs to be taken into account when assessing the added value of ESS beyond lumen diameter in highly stenotic lesions. Show less
Uusitalo, V.; Kamperidis, V.; Graaf, M.A. de; Maaniitty, T.; Stenstrom, I.; Broersen, A.; ... ; Knuuti, J. 2017
The objective of this dissertation was to establish the value of QCT to further enhance the clinical applicability and accuracy of coronary CTA. The automatic characterization of coronary... Show more The objective of this dissertation was to establish the value of QCT to further enhance the clinical applicability and accuracy of coronary CTA. The automatic characterization of coronary atherosclerosis with QCT is feasible and correlates well with IVUS VH. Secondly, novel CTA risk score was created incorporating detailed information on the location, severity and composition of atherosclerosis as assessed with QCT. This CTA risk score allows accurate risk stratification of patients with suspected CAD. A drawback of coronary CTA is the fact that the hemodynamic significance of a lesion cannot be evaluated. In this thesis it was demonstrated that QCT provided better correlation with the presence of myocardial ischemia on SPECT MPI as compared to current visual assessment of coronary CTA. With regards to the specific setting of high risk diabetic patients without chest pain syndrome several conclusion can be derived from this thesis. First, if treated with optimal medical therapy, very few patients present with progression of myocardial ischemia. Second, the prognosis of these patients is good; the overall long-term event-rate is limited. Especially diabetic patients without CAD on coronary CTA have an excellent prognosis. Show less