Objectives The aim of this study was to investigate the relationship between platelet reactivity (PR) after a loading dose (LD) of prasugrel and thrombotic events. Background Post-treatment PR has ...been shown to be strongly associated with the occurrence of major adverse cardiac events (MACE) after percutaneous coronary intervention (PCI) in the clopidogrel era. Prasugrel is a new P2Y12 –adenosine diphosphate receptor with a higher potency on PR. Methods A prospective multicenter study included patients who underwent successful PCI for acute coronary syndromes and received prasugrel therapy. Vasodilator-stimulated phosphoprotein (VASP) index was measured after the prasugrel LD. High on-treatment PR was defined as a VASP index ≥50%. MACE included cardiovascular death, myocardial infarction, and definite stent thrombosis at 1 month. Results Three hundred one patients were enrolled. The mean VASP index after 60 mg of prasugrel was 34.3 ± 23.1%. High on-treatment PR was observed in 76 patients (25.2%). Patients experiencing thrombotic events after PCI had significantly higher VASP indexes compared with those free of events (64.4 ± 14.4% vs. 33.4 ± 22.7%; range: 51% to 64% and 5% to 47.6%, respectively; p = 0.001). Kaplan-Meier analysis comparing good responders and patients with high on-treatment PR demonstrated a significantly higher rate of MACE in patients with suboptimal PR inhibition (log-rank p < 0.001). Receiver-operating characteristic curve analysis found a cutoff value of 53.5% of the VASP index to predict thrombotic events at 1 month (r = 0.86, p < 0.001). Patients with minor or major Thrombolysis In Myocardial Infarction unrelated to coronary artery bypass grafting bleeding and those without had similar VASP indexes (30 ± 17.8% vs. 34.3 ± 23%, p = 0.70). Conclusions Despite the use of prasugrel, a significant number of patients undergoing PCI in the setting of acute coronary syndromes do not achieve optimal PR inhibition. Such patients have a higher risk for MACE after PCI.
Stent thrombosis remains a significant pitfall of percutaneous coronary intervention (PCI). A recent trial observed that an adjusted loading dose (LD) of clopidogrel according to platelet monitoring ...decreases the rate of major adverse cardiovascular events after PCI. We investigated if such a strategy of a tailored clopidogrel LD according to platelet reactivity monitoring could decrease the rate of stent thrombosis. This multicenter prospective randomized study included 429 patients with a low clopidogrel response after a 600-mg LD undergoing PCI. Patients were randomized to a control group (n = 214) and to a vasodilator-stimulated phosphoprotein (VASP)-guided group (n = 215). In the VASP-guided group, patients received up to 3 additional 600-mg LDs of clopidogrel to obtain a VASP index <50% before PCI. The primary end point was the rate of stent thrombosis at 1 month. Secondary end points were rates of major adverse cardiovascular events and bleeding. Patients in the 2 groups had a high body mass index and were often diabetic (control vs VASP-guided group 28 ± 5.1 vs 27.9 ± 4.7 kg/m 2 , p = 0.8, and 39% vs 33%, p = 0.2, respectively). PCI was performed in most patients for acute coronary syndrome in the 2 groups (52.3% vs 50.7%, p = 0.8). Despite a 2,400-mg LD of clopidogrel, 8% of patients in the VASP-guided group remained low responders. The rate of stent thrombosis was significantly lower in the VASP-guided group (0.5% vs 4.2%, p <0.01). The rate of major adverse cardiovascular events was also higher in the control group (8.9% vs 0.5%, p <0.001). There was no difference in the rate of bleeding (2.8% vs 3.7%, p = 0.8). In conclusion, a tailored clopidogrel LD according to platelet reactivity monitoring decreases the rate of early stent thrombosis after PCI without increasing bleeding.
In this study, we investigated the Zicavo Metamorphic Complex (southern Corsica), which is part of the innermost Axial Zone of the Corsica-Sardinia Variscan belt. To better evaluate its geological ...and structural outline, a 1:5000 geological map, coupled with new structural/microstructural and petrographic data, is presented. The complex is formed by three tectonic units, from bottom to top: (i) an Orthogneiss Unit, (ii) a Leptyno-Amphibolite Unit, and (iii) a Micaschist Unit. They are separated by ductile shear zones with a top-to-the-SE sense of shear. They underwent a polyphase deformation and polymetamorphic history, with a shortening stage in the amphibolite facies, responsible for the main structures and shearing, followed by an exhumation phase.
To evaluate the feasibility and accuracy of quantification of calcified coronary stenoses using virtual non-calcium (VNCa) images in coronary CT angiography (CCTA) with photon-counting detector (PCD) ...CT compared with quantitative coronary angiography (QCA).
This retrospective, institutional-review board approved study included consecutive patients with calcified coronary artery plaques undergoing CCTA with PCD-CT and invasive coronary angiography between July and December 2022. Virtual monoenergetic images (VMI) and VNCa images were reconstructed. Diameter stenoses were quantified on VMI and VNCa images by two readers. 3D-QCA served as the standard of reference. Measurements were compared using Bland-Altman analyses, Wilcoxon tests, and intraclass correlation coefficients (ICC).
Thirty patients mean age, 64 years ± 8 (standard deviation); 26 men with 81 coronary stenoses from calcified plaques were included. Ten of the 81 stenoses (12%) had to be excluded because of erroneous plaque subtraction on VNCa images. Median diameter stenosis determined on 3D-QCA was 22% (interquartile range, 11%-35%; total range, 4%-88%). As compared with 3D-QCA, VMI overestimated diameter stenoses (mean differences -10%,
< .001, ICC: .87 and -7%,
< .001, ICC: .84 for reader 1 and 2, respectively), whereas VNCa images showed similar diameter stenoses (mean differences 0%,
= .68, ICC: .94 and 1%,
= .07, ICC: .93 for reader 1 and 2, respectively).
First experience in mainly minimal to moderate stenoses suggests that virtual calcium removal in CCTA with PCD-CT, when feasible, has the potential to improve the quantification of calcified stenoses.
The Paleozoic French Variscan Belt in Massif Central and Massif Armoricain is a collision belt that provides a good example of a suture zone where ophiolites are rare, and the frontal (i.e., the ...magmatic arc) part of the upper plate is not present. In the lower plate (or Gondwana), the continental rocks are subdivided into an Upper Gneiss Unit (UGU) and a Lower Gneiss Unit (LGU). The UGU experienced a high‐pressure (and likely ultra‐high‐pressure) metamorphism followed by crustal melting during their exhumation. New chemical U‐Th‐Pb monazite ages and ion‐probe U‐Pb zircon ages on migmatites allow us to constrain the P‐T‐t paths followed by the UGU and LGU. By comparison with thermomechanical experiments, a possible geodynamic evolution scenario can be proposed for the Variscan convergence. The high‐compression regime of continental subduction developed during the initial subduction of the northern margin of Gondwana under Armorica in Silurian times. This induced the formation of a new subduction zone in the back‐arc basin, which is the youngest, hottest, and thus mechanically the weakest part of the overriding plate. As a result, the arc‐back‐arc basin domain has been almost totally subducted below Armorica. Only a limited part of the back‐arc basin rocks remains exposed in the Devonian St‐Georges‐sur‐Loire Unit. Subsequently, the continental subduction of Gondwana resumed with a steeper dip associated with low‐compression regime that in turn allowed the high‐pressure rocks to be exhumed and partly melted in Late Devonian times. Such a scheme depicts quite well the complexity of the Variscan Belt.
Background The purpose of the study was to determine the long-term prognostic value of normal adenosine stress cardiac magnetic resonance imaging (CMR) in patients referred for evaluation of ...myocardial ischemia. Methods We reviewed 300 consecutive patients (age 65 ± 11 years, 74% male) with suspected or known coronary disease and normal wall motion who had undergone adenosine stress CMR negative for ischemia and scar. Most patients were at intermediate risk of coronary artery disease. The end points studied were all causes of mortality and major adverse cardiac events, including cardiac death, myocardial infarction, revascularization, and hospitalization for unstable angina. Results During a mean follow-up of 5.5 years (mean = 5.4 ± 1.1), 16 patients died because of various causes (cardiac death in 5 patients). Three patients had a nonfatal myocardial infarction, 7 patients were hospitalized for revascularization, and 11 were medically treated for unstable angina. The annual cardiac event rate was 1.3% (0.78% in the first 3 years and 1.9% between the fourth and sixth years). The predictors of major adverse cardiac events in a multivariate analysis model were as follows: advanced age (hazard ratio HR 1.15, 95% confidence interval 95% CI 1.02-1.30), diabetes (HR 17.5, 95% CI 2.2-140), and the habit of smoking (HR 5.9, 95% CI 1.0-35.5). For all causes of mortality, the only predictor was diabetes (HR 11.4, 95% CI 1.76-74.2). Patients with normal stress CMR had an excellent outcome during the 3 years after the study. The cardiac event rate was higher between the fourth and sixth years. Conclusion Over a 5.5-year period, a low event rate and excellent prognosis occurred in patients with normal adenosine stress CMR. Low- to intermediate-risk patients with a normal CMR are at low risk for subsequent cardiac events.
A paucity of data on outcome of coronary multislice computed tomography (CT) is available. The aim of this study was to assess the long-term follow-up of 64-slice CT in a homogenous patient group. In ...total 222 patients (136 men, 61%, 59 ± 11 years of age) with chest pain at intermediate risk of coronary artery disease (CAD) and no previous CAD underwent 64-slice CT. Coronary lesions were considered significant or not based on a threshold of 50% luminal narrowing. Plaques were classified as calcified, noncalcified, and mixed based on type. End point during follow-up was major adverse cardiac events (nonfatal myocardial infarction, unstable angina requiring hospitalization, myocardial revascularization). Coronary plaques were detected in 162 patients (73%). Coronary artery stenosis was significant in 62 patients. Normal arteries were found in 59 patients (27%). During a mean follow-up of 5 ± 0.5 years, 30 cardiac events occurred. Annualized event rates were 0% in patients with normal coronary arteries, 1.2% in patients with nonsignificant stenosis, and 4.2% in patients with significant stenosis (p <0.01). Predictors of cardiac events were presence of significant stenosis, proximal stenosis, and multivessel disease. Noncalcified and mixed plaques had the worse prognosis (p <0.05). In conclusion, 64-CT provides long-term incremental value in patients at intermediate risk of CAD.
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