Pressure Wire Used to Measure Gradient in Chronic Mesenteric Ischemia

Chronic mesenteric ischemia is a rare disorder in the United States. Frequently, its symptoms correlate poorly with the angiographically apparent degree of mesenteric artery stenosis. Measuring the pressure gradient with a small-caliber catheter is an established means of determining whether a particular stenosis is flow-limiting, thus guiding the interventional decision when stenoses are of indeterminate angiographic significance. Using a 0.014-in guidewire, however, is potentially more accurate because it eliminates any measurement error attributable to the use of a larger, potentially obstructive catheter. We present a case of chronic mesenteric ischemia in a 70-year-old woman who had abdominal pain with multiple possible causes. We used a 0.014-in pressure wire to calculate pressure gradients and guide our decision to stent tandem lesions in the superior mesenteric artery. After revascularization, the patient''s symptoms improved dramatically. To the best of our knowledge, this is the first published case in which a pressure wire was used to measure a pressure gradient in chronic mesenteric ischemia.Key words: Mesenteric arteries/pathology, mesenteric ischemia, chronic, mesenteric vascular occlusion/diagnosis/therapy, mesentery/blood supply, peripheral vascular diseases/therapy, pressure gradient, pressure wire, splanchnic circulationRecent technical advances in vascular imaging have led to increased recognition of pervasive atherosclerotic plaques. The resulting clinical challenge has been to correlate anatomic findings with the clinical presentation. Using angiography alone may lead one to underestimate or overestimate the significance of visually apparent stenoses.^1,2 Techniques for measuring stenosis severity physiologically have been introduced to help overcome these problems. The pressure gradient across a lesion, measured directly and in vivo, is likely to be the most helpful guide in this regard. The use of small-caliber catheters to measure intravascular gradients has been well established, but the results must be interpreted with caution because of the potential flow obstruction caused by the measuring catheter itself. For this reason, using a 0.014-in pressure wire to measure the translesional pressure gradient can provide more precise information.We present the case of a 70-year-old woman whose symptoms, although atypical, had features that suggested chronic mesenteric ischemia (CMI). We measured the pressure gradient across 2 tandem stenoses of uncertain severity in the proximal superior mesenteric artery (SMA) to guide our decision to stent. We believe that this is the first published case in which a pressure wire was used to measure translesional pressure gradients in a patient with CMI.     

Heart transplant recipients with confirmed 2019 novel coronavirus infection: The Detroit experience

A chronic immunosuppressed state as in solid organ transplant recipients is a reported risk factor for the novel 2019 coronavirus infection. Patients with a history of orthotopic heart transplant (OHT) at a tertiary care transplant center in Detroit, Michigan were retrospectively reviewed from March until May 2020. Clinical parameters and outcomes of 5 OHT recipients and one combined heart–lung recipient with confirmed SARS-CoV-2 were obtained. The cohort was predominately African American males with median age of 59 years (interquartile range, 48.25-73.25). All patients were classified as having mild–moderate disease; none required intubation or ICU admission with no deaths. The most common presenting symptoms were fever and shortness of breath 83% (n = 5), followed by cough and chills 67% (n = 4). All admitted patients (n = 5) received hydroxychloroquine and 3 received high-dose steroids. Antimetabolites were held for 2 patients (33.3%). The calcineurin inhibitor trough goal was decreased in only 1 patient; 3 other patients, without change in goal, required calcineurin inhibitor dosage reduction. Two patients requiring readmission presented 7 and 23 days after initial symptoms onset. In conclusion, our experience with OHT patients infected by the SARS-CoV-2 virus did not have an elevated risk of severe infection. Impact of modifying immunosuppression remains unclear.     

Initial evidence of endothelial cell apoptosis as a mechanism of systemic capillary leak syndrome

BACKGROUND: Systemic capillary leak syndrome (SCLS) is a rare disorder of unknown etiology that is characterized by acute recurrent attacks of hypovolemic shock commonly following an inflammatory stimulus such as a viral illness. Prophylactic therapy is generally ineffective, and the outcome is frequently fatal. METHODS: In order to investigate the cellular mechanisms leading to SCLS, we examined the effects of sera from two patients with active SCLS on microvascular endothelial cell apoptosis in vitro. Apoptosis was determined by morphologic criteria, DNA fragmentation, annexin V stain, and by a quantitative photometric assay. The apoptotic pathway was investigated by Western blot of endothelial cells lysate after exposure to SCLS sera. RESULTS: The sera from patients with active SCLS mediated profound apoptosis of microvascular endothelial cells shortly after exposure. The exposed microvascular endothelial cells underwent immediate apoptosis as evidenced by morphologic changes, plasma membrane phosphatidylserine exposure, and by DNA fragmentation. Increased Bax/Bcl-2 ratio in endothelial cells exposed to SCLS sera was observed and suggested an oxidation injury as the possible mechanism for endothelial apoptosis. This potential mechanism was further explored by measuring intracellular reactive oxygen species (ROS) following SCLS serum exposure. Sera from both patients caused marked increases in ROS, initially detectable at 1 h and persisted for at least 12 h, with control serum from healthy subjects showing no effect on basal endothelial cell ROS concentrations. CONCLUSION: Components from the sera of patients with active systemic capillary leak syndrome in contrast to healthy subject sera mediate early and extensive endothelial apoptosis in vitro that is associated with oxidation injury. These data represent compelling initial evidence for oxidation-induced apoptosis as a likely mechanism for endothelial injury leading to SCLS.     

Respiratory involvements among women exposed to the smoke of traditional biomass fuel and gas fuel in a district of Bangladesh

Objectives

Burning of biomass fuel (cow-dung, crop residue, dried leaves, wood, etc.) in the kitchen releases smoke, which may impair the respiratory functions of women cooking there. This paper aimed to compare the respiratory symptoms between biomass fuel users and gas fuel users in Bangladesh.

Methods

A cross-sectional survey was conducted through face-to-face interviews and chest examination of 224 adult women using biomass fuel in a rural village and 196 adult women using gas fuel in an urban area.

Results

The prevalence of respiratory involvement (at least one among nine symptoms and two diseases) was significantly higher among biomass users than among gas users (29.9 vs. 11.2 %). After adjustment for potential confounders by a logistic model, the odds ratio (OR) of the biomass users for the respiratory involvement was significantly higher (OR = 3.23, 95 % confidence interval 1.30–8.01). The biomass fuel use elevated symptoms/diseases significantly; the adjusted OR was 3.04 for morning cough, 7.41 for nasal allergy, and 5.94 for chronic bronchitis. The mean peak expiratory flow rate of biomass users (253.83 l/min) was significantly lower than that of gas users (282.37 l/min).

Conclusions

The study shows significant association between biomass fuel use and respiratory involvement among rural women in Bangladesh, although the potential confounding of urban/rural residency could not be ruled out in the analysis. The use of smoke-free stoves and adequate ventilation along with health education to the rural population to increase awareness about the health effects of indoor biomass fuel use might have roles to prevent these involvements.     

Effects of Graphene Oxide and Crumb Rubber on the Fresh Properties of Self-Compacting Engineered Cementitious Composite Using Response Surface Methodology

Graphene oxide-modified rubberized engineered cementitious composite (GO-RECC) is attracting the attention of researchers because of the reported benefits of the GO and crumb rubber (CR) on the strength and deformation properties of the composite. While it is well established that GO negatively affects the workability of cementitious composites, its influence on the attainment of the desired self-compacting (SC) properties of ECC has not yet been thoroughly investigated, especially when combined with crumb rubber (CR). In addition, to simplify the number of trial mixes involved in designing SC-GO-RECC, there is a need to develop and optimize the process using Design of Experiment (DOE) methods. Hence, this research aims to investigate and model using response surface methodology (RSM), the combined effects of the GO and CR on the SC properties of ECC through the determination of T₅₀₀, slump flow, V-funnel, and L-box ratio of the SC-GORECC as the responses, following the European Federation of National Associations Representing for Concrete (EFNARC) 2005 specifications. The input factors considered were the GO by wt.% of cement (0.02, 0.04, 0.06, and 0.08) and CR as a replacement of fine aggregate by volume (5, 10, and 15%). The results showed that increasing the percentages of GO and CR affected the fresh properties of the SC-GORECC adversely. However, all mixes have T₅₀₀ of 2.4 to 5.2 s, slump flow of 645 to 800 mm, V-funnel time of 7.1 to 12.3 s, and L-box ratio (H2/H1) of 0.8 to 0.98, which are all within acceptable limits specified by EFNARC 2005. The developed response prediction models were well fitted with R² values ranging from 91 to 99%. Through the optimization process, optimal values of GO and CR were found to be 0.067% and 6.8%, respectively, at a desirability value of 1.0.     

Use of short-term steroids in the prophylaxis of atrial fibrillation after cardiac surgery

Objectives

To assess the effectiveness of corticosteroids in the prophylaxis of postoperative atrial fibrillation (AF) in patients undergoing elective coronary artery bypass grafting or valvular heart surgery in terms of reducing its incidence and decreasing the length of hospital stay.