Does the weekend effect exist for acute type A aortic dissection?-a retrospective case-control study.

Background: The weekend effect refers to the mortality difference for patients admitted/operated on weekends compared to those on weekdays. The study aimed to provide new evidence on the impact of the weekend effect on acute type A aortic dissection (ATAAD). Methods: Primary endpoints were operative mortality, stroke, paraplegia, and continuous renal replacement therapy (CRRT). A meta-analysis of current evidence on the weekend effect was first conducted. Analyses based on single-center data (retrospective, case-control study) were further performed. Results: A total of 18,462 individuals were included in the meta-analysis. The pooled results showed that mortality was not significantly higher for ATAAD on weekends compared to that on weekdays [odds ratio (OR): 1.16, 95% CI: 0.94-1.43]. The single-center cohort included 479 patients, which also showed no significant differences in primary and secondary outcomes between the two groups. The unadjusted OR for weekend group over weekday group was 0.90 (95% CI: 0.40-1.86, P=0.777). The adjusted OR for weekend group was 0.94 (95% CI: 0.41-2.02, P=0.880) controlling for significant preoperative factors, and 0.75 (95% CI: 0.30-1.74, P=0.24) controlling for significant preoperative and operative factors altogether. In PSM matched cohort, the operative mortality was still comparable between the weekend group [10 (7.2%)] and weekday group [9 (6.5%)] (P=1.000). No significant survival difference was observed between the two groups (P=0.970). Conclusions: The weekend effect was not found to be applicable to ATAAD. However, clinicians should be cautious of the weekend effect as it is disease-specific and may vary across healthcare systems.

How credit default swap market measures carbon risk.

Given the increasing concerns about the carbon risk's influence on economy, this paper is aimed at exploring the impact of carbon emission on credit risk, measured by credit default swap. By using monthly updated data of 363 unique US companies among a period between 2007 and 2020, we uncover that firm's direct carbon emission increases its CDS spreads, whereas indirect emission is not priced by credit market seriously. Considering dynamic effects of carbon risk, we find a positive correlation between carbon risk and the CDS term structure, which implies that carbon risk's influence on long-term concern of credit risk can be more pronounced. Using exogenous shock: Paris Agreement, our finding remains robust. Finally, we also examine potential channels, including companies' sustainability awareness, green transition willingness, and ability, through which carbon risk is priced among the credit market. This paper provides further evidence of carbon credit premium and contributes to the implications of carbon cutting activities.

Right axillary artery cannulation in acute type A aortic dissection with involvement of the right axillary artery.

OBJECTIVE: The right axillary artery is currently recommended for arterial cannulation in surgery for acute type A aortic dissection. However, the feasibility of cannulation on a dissected right axillary artery remains undetermined. The objective was to examine the feasibility of cannulation on a dissected right axillary artery. METHODS: From 2016 to 2020, 835 patients who underwent acute type A aortic dissection repair were included in this study. Cannulation strategy and perioperative outcomes of patients who did and did not have right axillary artery dissection were compared. Propensity score matching and logistic regression were applied. RESULTS: A total of 124 patients had right axillary artery dissection, and 711 patients did not. Direct right axillary artery cannulation was used for cardiopulmonary bypass in the majority of patients, but with a lower rate in patients with right axillary artery dissection (n = 88 [71.0%] vs n = 579 [81.4%], P = .007). Right axillary artery cannulation failure (n = 3 [2.4%] vs n = 5 [0.7%], P = .102) and related complications (n = 1 [0.8%] vs n = 6 [0.8%], P = 1.000) were rare in both groups. In-hospital mortality (n = 18 [14.5%] vs n = 59 [8.3%], P = .027) and stroke (n = 14 [11.3%] vs n = 42 [5.9%], P = .027) were significantly higher in the right axillary artery dissection group, but after propensity score matching, in-hospital outcomes were comparable. Right axillary artery dissection was not a risk factor for mortality, stroke, right axillary artery cannulation not performed, or right axillary artery cannulation failure. CONCLUSIONS: Direct right axillary artery cannulation is feasible for most patients with acute type A aortic dissection with right axillary artery dissection.

Surgical treatment strategies for patients with type A aortic dissection involving arch anomalies.

Objective: The aim of the study was to investigate surgical modalities and outcomes in patients with type A aortic dissection involving arch anomalies. Method: Patients with type A aortic dissection who underwent surgical treatment at our center between January 2017 and 31 December 2020 were selected for this retrospective analysis. Data including computed tomography (CT), surgical records, and cardiopulmonary bypass records were analyzed. Perioperatively survived patients were followed up, and long-term mortality and aortic re-interventions were recorded. Result: A total of 81 patients with arch anomalies were included, 35 with "bovine" anomalies, 23 with an aberrant right subclavian artery, 22 with an isolated left vertebral artery, and one with a right-sided arch + aberrant left subclavian artery. The strategies of arch management and cannulation differed according to the anatomic variation of the aortic arch. In total, seven patients (9%) died after surgery. Patients with "bovine" anomalies had a higher perioperative mortality rate (14%) and incidence of neurological complications (16%). Overall, four patients died during the follow-up period, with a 6-year survival rate of 94.6% (70/74). A total of four patients underwent aortic re-intervention during the follow-up period; before the re-intervention, three received the en bloc technique (13.6% 3/22) and one received hybrid therapy (11.1% 1/9). Conclusion: With complete preservation and reconstruction of the supra-arch vessels, patients with type A aortic dissection combining arch anomalies can achieve a favorable perioperative prognostic outcome. Patients who received the en bloc technique are more likely to require aortic re-intervention than patients who underwent total arch replacement with a four-branched graft vessel. Cannulation strategies should be tailored according to the variation of anatomy, but routine cannulation with the right axillary artery can still be performed in most patients with arch anomalies, even for patients with an aberrant right subclavian artery.

Aortic Balloon Occlusion Technique Does Not Improve Peri-Operative Outcomes for Acute Type A Acute Aortic Dissection Patients With Lower Body Malperfusion.

Background: The management of malperfusion is vital to improve the outcomes of surgery for acute type A acute aortic dissection (ATAAD). Open arch repair under hypothermic circulatory arrest with selective antegrade cerebral perfusion (HCA/sACP) is safe and efficient but associated with inevitable hypothermia and ischemia-reperfusion injury. The aortic balloon occlusion (ABO) technique is shown to be organ protective by allowing higher temperature and shorter circulatory arrest time. In this study, we aimed to evaluate the safety and efficacy of this new technique for ATAAD patients with lower body malperfusion. Methods: Between January 2013 and November 2020, 355 ATAAD patients with lower body malperfusion who underwent arch repair in our institute were enrolled. The patients were divided into 2 groups: ABO group (n = 85) and HCA/sACP group (n = 271). Propensity score matching was performed to correct baseline differences. Results: Using the propensity score matching, 85 pairs were generated. Circulatory arrest time was significantly lower in the ABO group compared with the HCA/sACP group (median, 8 vs. 22 min; p < 0.001). The incidence of in-hospital mortality (10.6 vs. 12.9%; p = 0.812), stroke (7.1 vs. 7.1%; p = 1.000), dialysis (25.9 vs. 32.9%; p = 0.183), hepatic dysfunction (52.9 vs. 57.6%; p = 0.537), tracheostomy (4.7 vs. 2.4%; p = 0.682), paraplegia (1.2 vs. 4.7%; p = 0.368) were comparable between ABO and HCA/sACP groups. Other outcomes and major adverse events were comparable. The multivariable logistic analysis did not recognize ABO technique protective against any major adverse outcomes. Conclusions: For ATAAD patients with lower body malperfusion, the ABO technique allows the performance of arch repair with frozen elephant trunk (FET) under higher temperature and shorter circulatory arrest time. However, ABO technique did not improve perioperative outcomes. Future studies are warranted to evaluate the efficacy of this technique.

Coronary Malperfusion Secondary to Acute Type A Aortic Dissection: Surgical Management Based on a Modified Neri Classification.

Background: Coronary malperfusion (CM) secondary to acute type A aortic dissection (ATAAD) is considered rare but has a high mortality rate. This study examined the incidence, management, and outcomes of patients with CM secondary to ATAAD and proposes a modified Neri classification. Methods: Between 2015 and 2020, out of 1018 patients who underwent surgical repair for ATAAD, 137 presented with CM, including 68 (49.6%), 43 (31.3%), and 15 (10.9%) with Neri types A, B, and C, respectively, and 11 (8.0%) with coronary orifice intimal tear (COIT), which we consider a novel category. Results: The occurrence rate of CM was 13.4%. CM was associated with higher in-hospital mortality (18.2% vs. 7.8%, p < 0.001). For Neri type A (98.5%) and most type B lesions (72.1%), coronary repair was adequate. Coronary artery bypass grafting (CABG) was necessary for type B patients unsuited for repair (23.2%) and for all type C patients (100%). Repair of COIT was possible (45.5%). The in-hospital mortality rates differed significantly among the four lesion groups (p = 0.006). Conclusions: The occurrence of CM secondary to ATAAD may be more frequent than previously reported. Surgical management based on lesion classification achieved acceptable outcomes. Repair was adequate for Neri type A and most type B lesions. Other type B and type C lesions could be treated by CABG. Coronary orifice intimal tear is a unique set of lesions, for which orifice repair was also possible.

Transcriptome and N6-Methyladenosine RNA Methylome Analyses in Aortic Dissection and Normal Human Aorta.

Objective: To investigate the N6-methyladenosine (m6A) modification and the expressions of the m6A regulatory genes in the acute aortic dissection (AD). Methods: MeRIP-seq and RNA-seq experiments of aortic media tissue samples obtained from AD (n = 4) and Controls (n = 4) were conducted. m6A methylation quantification was used to measure the total mRNA m6A level. The five m6A regulators mRNA expressions were analyzed by quantitative polymerase chain reaction (qPCR). Western blot analyses and immunofluorescence staining were used to detect the difference of METTL14 protein expression in the aortas of AD and Normal. Results: Among AD patients, we detected significantly elevated levels of m6A in total RNA. Compared with the normal group, the up methylated coding genes of AD were primarily enriched in the processes associated with extracellular fibril organization, while the genes with down methylation were enriched in the processes associated with cell death regulation. Furthermore, many differentially methylated m6A sites (DMMSs) coding proteins were mainly annotated during the extracellular matrix and inflammatory responses. Conclusions: These findings indicate that differential m6A methylation and m6A regulatory genes, including MTEEL14 and FTO, may act on functional genes through RNA modification, thereby regulating the pathogenesis of aortic dissection.

Hydroxyapatite nanocrystals stimulate osteogenic differentiation in primary human aortic smooth muscle cells by activation of oxidative stress and the ERK pathway.

BACKGROUND: Hydroxyapatite nanocrystal (HN) deposition underlies the development of vascular calcification, which is an actively regulated process resembling bone formation. This study investigated the role of HNs in inducing osteogenic differentiation of primary human aortic smooth muscle cells (HASMCs). METHODS: Primary HASMCs were incubated with HNs, cell osteogenic differentiation was evaluated by von kossa staining and calcium content. The expressions of SM-α-actin and bone markers, including runt-related transcription factor 2 (Runx2), osteopontin (OPN), osterix, and collagen 1 (COL1) were also determined. Antioxidants, ERK-specific inhibitor were used to examine whether oxidative stress and the ERK pathway were required for this transition. RESULTS: Stimulation of HASMCs with HNs increased calcium deposition, expression of bone markers and decreased SM-α-actin expression. HNs produced reactive oxygen species (ROS) in HASMCs, as evaluated by fluorescent probe. Antioxidants inhibited HN-induced osteogenic differentiation. Furthermore, the inhibitor of the ERK pathway, PD98059, suppressed the effect of HNs on bone marker expression. CONCLUSIONS: These findings suggest that HNs stimulated osteogenic differentiation of vascular smooth muscle cells that build biomineralized deposits partly by activating oxidative stress and the ERK pathway.

Calcium Phosphate Crystals from Uremic Serum Promote Osteogenic Differentiation in Human Aortic Smooth Muscle Cells.

Recent study demonstrated that calcium phosphate (CaP) crystals isolated from high phosphate medium were a key contributor to arterial calcification. The present study further investigated the effects of CaP crystals induced by uremic serum on calcification of human aortic smooth muscle cells. This may provide a new insight for the development of uremic cardiovascular calcification. We tested the effects of uremic serum or normal serum on cell calcification. Calcification was visualized by staining and calcium deposition quantified. Expression of various bone-calcifying genes was detected by real-time PCR, and protein levels were quantified by western blotting or enzyme-linked immunosorbent assays. Pyrophosphate was used to investigate the effects of CaP crystals' inhibition. Finally, CaP crystals were separated from uremic serum to determine its specific pro-calcification effects. Uremic serum incubation resulted in progressively increased calcification staining and increased calcium deposition in HASMCs after 4, 8 and 12 days (P vs 0 day <0.001 for all). Compared to cells incubated in control serum, uremic serum significantly induced the mRNA expression of bone morphogenetic factor-2, osteopontin and RUNX2, and increased their protein levels as well (P < 0.05 for all). Inhibition of CaP crystals with pyrophosphate incubation prevented calcium deposition and bone-calcifying gene over-expression increased by uremic serum. CaP crystals, rather than the rest of uremic serum, were responsible for these effects. Uremic serum accelerates arterial calcification by mediating osteogenic differentiation. This effect might be mainly attributed to the CaP crystal content.

Impact of break-in period on the short-term outcomes of patients started on peritoneal dialysis.

OBJECTIVES: Peritoneal dialysis (PD) is one of the first-line modalities of renal replacement therapy in patients with end-stage renal disease. Guidelines recommended a break-in period of at least 2 weeks before full PD start. However, the optimal duration of the break-in period is still unclear. In the present study, we investigated the effect of various break-in periods on short-term outcomes in patients on PD. ♢ METHODS: All patients who underwent Tenckhoff catheter implantation and initiated PD in Renji Hospital, Shanghai Jiao Tong University School of Medicine, between 1 January 2001 and 31 December 2010 were included. Patients were grouped according to the duration of their break-in period: 7 days or less (BI ≤ 7), 8 - 14 days (BI8-14), and more than 14 days (BI>14). Kaplan-Meier curves and log-rank tests were used to compare short-term outcomes in the various groups. ♢ RESULTS: Our study enrolled 657 patients (44.5% men), of whom 344, 137, and 176 patients were in the respective break-in groups. Compared with BI>14 patients, BI ≤ 7 patients had a lower estimated glomerular filtration rate (5.34 ± 1.86 mL/min/1.73 m(2) vs 6.55 ± 1.71 mL/min/1.73 m(2), p < 0.001) and lower serum albumin (33.29 ± 5.36 g/L vs 36.64 ± 5.40 g/L, p < 0.001). The incidence of mechanical complications during the first 6 months was significantly higher in BI ≤ 7 patients than in BI>14 patients (8.4% vs 1.7%, p = 0.004). However, we observed no significant differences between the three groups with respect to the prevalence of catheter dysfunction requiring surgical intervention (p > 0.05). Logistic regression analysis showed that BI ≤ 7 [relative risk: 4.322; 95% confidence interval (CI): 1.278 to 14.608; p = 0.019] was an independent predictor of catheter dysfunction, but not of catheter dysfunction requiring surgical intervention (p > 0.05). Catheter dysfunction [hazard ratio (HR): 20.087; 95% CI: 7.326 to 55.074; p < 0.001] and peritonitis (HR: 4.533; 95% CI: 1.748 to 11.751; p = 0.002) were risk factors for technique failure during the first 6 months, but BI ≤ 7 was not correlated with technique failure. ♢ CONCLUSIONS: Patients starting PD with a break-in period of less than 1 week might experience a minor increased risk of mechanical complications, but no major effect on technique survival.