Application of ex vivo cryo-imaging technique for three-dimensional finite element analysis of atherosclerotic plaque rupture

PublishedCryo-imaging is an ex vivo vascular imaging modality that acquires serial 2D fluorescence and bright-field images at 20μm increments without sacrifice to tissue morphology. These features make Cryo-imaging an attractive approach for rendering high-resolution 3D volumes that may serve as a basis for finite element analysis (FEA) studies of plaque rupture. This work demonstrates the first use of Cryo-imaging for the imaging of a human coronary vessel and the subsequent rendering of a 3D FE model that clearly delineates critical anatomical features of atherosclerotic plaque. FEA is then performed to assess the plaque rupture conditions that result in a thrombotic episode

Serial Assessment of Vessel Interactions After Drug-Eluting Stent Implantation in Unprotected Distal Left Main Coronary Artery Disease Using Frequency-Domain Optical Coherence Tomography

ObjectivesThis study sought to assess stent-vessel interactions after drug-eluting stent (DES) implantation in unprotected left main coronary artery (ULM) by frequency-domain optical coherence tomography (FD-OCT).BackgroundPercutaneous coronary intervention using DES in ULM has been increasingly performed in routine practice. Recently, FD-OCT assessments of DES-vessel interactions have been used as surrogates for DES safety; however, there are no FD-OCT studies in ULM.MethodsWe prospectively enrolled 33 consecutive patients with ULM disease treated with sirolimus- (n = 11) and everolimus-eluting stents (n = 22). FD-OCT assessments were performed post-percutaneous coronary intervention and at 9-month follow-up. Three different segments of ULM were compared: distal (DIS), bifurcation (BIF), and ostial-body (BODY). The primary endpoints were percentages of uncovered and malapposed struts at 9-month follow-up, and the secondary endpoint was neointimal hyperplasia area.ResultsWe analyzed 25,873 stent struts. Significant differences were demonstrated for percentage of uncovered struts (3.4%, 11.7%, and 18.7%, respectively for DIS, BIF, and BODY; p < 0.05 for all the comparisons). Malapposition was also more common in BODY (5.3%) than in DIS (0.6%) and BIF (2.0%) segments (p < 0.05 for BODY vs. DIS, and BODY vs. BIF). Equivalent neointimal hyperplasia areas were demonstrated in all segments. Acute malapposition rates led to different patterns of DES-vessel interactions at 9-month follow-up.ConclusionsDistinct patterns of DES-vessel interactions were demonstrated in different segments of ULM. Acute stent strut malapposition affects these findings

Testosterone replacement therapy among HIV-infected men in the CFAR Network of Integrated Clinical Systems

The objectives of this study were to determine the rate of testosterone replacement therapy (TRT) initiation, TRT predictors and associated monitoring in HIV-infected men

The ability of contemporary cardiologists to judge the ischemic impact of a coronary lesion visually

Background: Landmark trials showed that invasive pressure measurement (Fractional Flow Reserve, FFR) was a better guide to coronary stenting than visual assessment. However, present-day interventionists have benefited from extensive research and personal experience of mapping anatomy to hemodynamics. Aims: To determine if visual assessment of the angiogram performs as well as invasive measurement of coronary physiology. Methods: 25 interventional cardiologists independently visually assessed the single vessel coronary disease of 200 randomized participants in The Objective Randomized Blinded Investigation with optimal medical Therapy of Angioplasty in stable angina trial (ORBITA). They gave a visual prediction of the FFR and Instantaneous Wave-free Ratio (iFR), denoted vFFR and viFR respectively. Each judged each lesion on 2 occasions, so that every lesion had 50 vFFR, and 50 viFR assessments. The group consensus visual estimates (vFFR-group and viFR-group) and individual cardiologists' visual estimates (vFFR-individual and viFR-individual) were tested alongside invasively measured FFR and iFR for their ability to predict the placebo-controlled reduction in stress echo ischemia with stenting. Results: Placebo-controlled ischemia improvement with stenting was predicted by vFFR-group (p < 0.0001) and viFR-group (p < 0.0001), vFFR-individual (p < 0.0001) and viFR-individual (p < 0.0001). There were no significant differences between the predictive performance of the group visual estimates and their invasive counterparts: p = 0.53 for vFFR vs FFR and p = 0.56 for viFR vs iFR. Conclusion: Visual assessment of the angiogram by contemporary experts, provides significant additional information on the amount of ischaemia which can be relieved by placebo-controlled stenting in single vessel coronary artery disease