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

Stimuli-Responsive Drug Delivery of Doxorubicin Using Magnetic Nanoparticle Conjugated Poly(ethylene glycol)-<i>g</i>-Chitosan Copolymer

Stimuli-responsive nanoparticles are regarded as an ideal candidate for anticancer drug targeting. We synthesized glutathione (GSH) and magnetic-sensitive nanocomposites for a dual-targeting strategy. To achieve this goal, methoxy poly (ethylene glycol) (MePEG) was grafted to water-soluble chitosan (abbreviated as ChitoPEG). Then doxorubicin (DOX) was conjugated to the backbone of chitosan via disulfide linkage. Iron oxide (IO) magnetic nanoparticles were also conjugated to the backbone of chitosan to provide magnetic sensitivity. In morphological observation, images from a transmission electron microscope (TEM) showed that IO nanoparticles were embedded in the ChitoPEG/DOX/IO nanocomposites. In a drug release study, GSH addition accelerated DOX release rate from nanocomposites, indicating that nanocomposites have redox-responsiveness. Furthermore, external magnetic stimulus concentrated nanocomposites in the magnetic field and then provided efficient internalization of nanocomposites into cancer cells in cell culture experiments. In an animal study with CT26 cell-bearing mice, nanocomposites showed superior magnetic sensitivity and then preferentially targeted tumor tissues in the field of external magnetic stimulus. Nanocomposites composed of ChitoPEG/DOX/IO nanoparticle conjugates have excellent anticancer drug targeting properties

Follow-up of Shelhigh porcine pulmonic valve conduits

BACKGROUND: We implanted Shelhigh porcine pulmonic valve conduits because of the limited availability of homografts in our country. The aim of this study was to evaluate the short-term results of SPVC. METHODS: From November 2002 to July 2005, the Shelhigh porcine pulmonic valve conduit was implanted in 73 patients (81 procedures) in the right ventricular outflow tract to correct congenital heart diseases. Operative procedures were Rastelli operation in 65, anatomic correction of atrioventricular discordance in 5, and Ross operation in 3. Age at operation was 6.8 +/- 7.5 years, including 11 patients under 1 year. The median conduit size was 18 mm (range, 12 to 24 mm). RESULTS: There was no operative mortality and 1 nonconduit-related late death (mean follow-up, 11.3 +/- 10.7 months). Ten conduits (12.3%, 7 patients) were removed at a median of 9.6 months (range, 2.5 to 25.4) owing to obstruction in 9 and pseudoaneurysm in 1. In the explanted conduits, we found a prominent intimal peel at the distal anastomosis without leaflet calcification. Freedom from reoperation at 24 months was 87% +/- 11.7% in large-sized conduits (>or=18 mm) and 62.8% +/- 10.6% in small-sized conduits (or=18 mm) fail after 2 years of implantation due to intimal peel formation at the distal segment