Relationship between tissue characterization with 40MHz intravascular ultrasound imaging and 64-slice computed tomography

AbstractBackgroundIdentification of coronary plaque composition is important for selecting the treatment strategy, and 64-slice computed tomography (CT) is a noninvasive method of characterizing atherosclerotic plaques. However, the correlation between plaque characteristics detected by CT and intravascular ultrasound (IVUS) is not clear. A 40MHz IVUS imaging system (iMap-IVUS) has recently been developed to evaluate plaque composition. The aim of this study was to compare iMap-IVUS with 64-slice CT angiography for the characterization of non-calcified coronary plaques.Methods and resultsBoth 64-slice CT angiography and iMap-IVUS were performed in 19 patients (38 plaques). CT values were measured as Hounsfield units (HU) in circular regions of interest (ROI) drawn on the plaques. The iMap-IVUS system analyzed coronary plaques as fibrotic, lipidic, necrotic, or calcified tissue based on the radiofrequency spectrum.A positive correlation was found between CT values and the percentage of fibrotic plaque (r=0.34, p=0.036) or calcified plaque (r=0.40, p=0.011). Conversely, a negative correlation was found between CT values and the percentage of lipidic plaque (r=−0.41, p=0.01), or necrotic plaque (r=−0.41, p=0.01).ConclusionsGood correlations were observed between the characteristics of non-calcified plaque determined by iMap-IVUS and the CT values of plaque detected by 64-slice CT scanning

Downregulation of macrophage Irs2 by hyperinsulinemia impairs IL-4-indeuced M2a-subtype macrophage activation in obesity

M2a-subtype macrophage activation is known to be impaired in obesity, although the underlying mechanisms remain poorly understood. Herein, we demonstrate that, the IL-4/Irs2/Akt pathway is selectively impaired, along with decreased macrophage Irs2 expression, although IL-4/STAT6 pathway is maintained. Indeed, myeloid cell-specific Irs2-deficient mice show impairment of IL-4-induced M2a-subtype macrophage activation, as a result of stabilization of the FoxO1/HDAC3/NCoR1 corepressor complex, resulting in insulin resistance under the HF diet condition. Moreover, the reduction of macrophage Irs2 expression is mediated by hyperinsulinemia via the insulin receptor (IR). In myeloid cell-specific IR-deficient mice, the IL-4/Irs2 pathway is preserved in the macrophages, which results in a reduced degree of insulin resistance, because of the lack of IR-mediated downregulation of Irs2. We conclude that downregulation of Irs2 in macrophages caused by hyperinsulinemia is responsible for systemic insulin resistance via impairment of M2a-subtype macrophage activation in obesity

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

What Should We Do after the COVID-19 Vaccination? Vaccine-Associated Diseases and Precautionary Measures against Adverse Reactions

COVID-19 vaccines have been used to counteract the global COVID-19 pandemic. While these are effective, adverse reactions have been reported, such as injection-site pain, muscle ache, fever, palpitation, and chest discomfort. The release of inflammatory cytokines, such as interleukin (IL)-6 and IL-1β, is a potential mechanism for post-vaccine side-effects. Chest discomfort after the vaccination, including myocarditis and acute coronary syndrome, is a particularly serious adverse reaction. It is important to be familiar with the differential diagnoses of chest discomfort and organ-specific diseases associated with COVID-19 vaccines as the preparation for booster shots and vaccinations among children aged 5–11 years begins. High-intensity exercise, alcohol, tobacco smoking, and baths promote inflammatory cytokines, such as IL-6, which may exacerbate the adverse reactions after vaccination. Japanese data show that deaths during baths are the most common for several days after mRNA vaccination. Additionally, alcohol and tobacco smoking were identified as predictive factors of lower antibody titers after vaccination. In this review, we aimed to provide a few recommendations to prevent vaccine-associated disease