The inhibitor of κB kinase ß (IKKß) phosphorylates IκBα twice in a single binding event through a sequential mechanism.

Phosphorylation of Inhibitor of κB (IκB) proteins by IκB Kinase ß (IKKß) leads to IκB degradation and subsequent activation of nuclear factor κB transcription factors. Of particular interest is the IKKß-catalyzed phosphorylation of IκBα residues Ser32 and Ser36 within a conserved destruction box motif. To investigate the catalytic mechanism of IKKß, we performed pre-steady-state kinetic analysis of the phosphorylation of IκBα protein substrates catalyzed by constitutively active, human IKKß. Phosphorylation of full-length IκBα catalyzed by IKKß was characterized by a fast exponential phase followed by a slower linear phase. The maximum observed rate (kp) of IKKß-catalyzed phosphorylation of IκBα was 0.32 s-1 and the binding affinity of ATP for the IKKß•IκBα complex (Kd) was 12 µM. Substitution of either Ser32 or Ser36 with Ala, Asp, or Cys reduced the amplitude of the exponential phase by approximately 2-fold. Thus, the exponential phase was attributed to phosphorylation of IκBα at Ser32 and Ser36, whereas the slower linear phase was attributed to phosphorylation of other residues. Interestingly, the exponential rate of phosphorylation of the IκBα(S32D) phosphomimetic amino acid substitution mutant was nearly twice that of WT IκBα and 4-fold faster than any of the other IκBα amino acid substitution mutants, suggesting that phosphorylation of Ser32 increases the phosphorylation rate of Ser36. These conclusions were supported by parallel experiments using GST-IκBα(1-54) fusion protein substrates bearing the first 54 residues of IκBα. Our data suggest a model wherein, IKKß phosphorylates IκBα at Ser32 followed by Ser36 within a single binding event.

Single versus multiple arterial grafting in diabetic patients at 10 years: the Arterial Revascularization Trial.

AIMS: To evaluate the impact of multiple arterial grafting (MAG) vs. single arterial grafting (SAG) in a post hoc analysis of 10-year outcomes in patients with diabetes mellitus (DM) from the Arterial Revascularization Trial (ART). METHODS AND RESULTS: The primary endpoint was all-cause mortality and the secondary endpoint was a composite of major adverse cardiac events (MACE) at 10-year follow-up. Patients were stratified by diabetes status (non-DM and DM) and grafting strategy (MAG vs. SAG). A total of 3020 patients were included in the analysis; 716 (23.7%) had DM. Overall, 55.8% non-DM patients received MAG and 44.2% received SAG, while 56.6% DM patients received MAG and 43.4% received SAG. The use of MAG compared with SAG was associated with lower 10-year mortality for both non-DM [17.7 vs. 21.0%, adjusted hazard ratio (HR) 0.87, 95% confidence interval (CI) 0.72-1.06] and DM patients (21.5 vs. 29.9%, adjusted HR 0.65, 95% CI 0.48-0.89; P for interaction = 0.12). For both groups, the rate of 10-year MACE was also lower for MAG vs. SAG. Overall, deep sternal wound infections (DSWIs) were uncommon but more frequent in the MAG vs. SAG group in both non-DM (3.3 vs. 2.1%) and DM patients (7.9 vs. 4.8%). The highest rates of DSWI were in insulin-treated patients receiving MAG (9.6 vs. 6.3%, when compared with SAG). CONCLUSION: In this post hoc analysis of the ART, MAG was associated with substantially lower mortality rates at 10 years after coronary artery bypass grafting in patients with DM. Patients with DM receiving MAG had a higher incidence of DSWI, especially if insulin dependent.

Single or multiple arterial bypass graft surgery vs. percutaneous coronary intervention in patients with three-vessel or left main coronary artery disease.

AIM: The aim of this study was to compare long-term all-cause mortality between patients receiving percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) using multiple (MAG) or single arterial grafting (SAG). METHODS AND RESULTS: The current study is a post hoc analysis of the SYNTAX Extended Survival Study, which compared PCI with CABG in patients with three-vessel (3VD) and/or left main coronary artery disease (LMCAD) and evaluated survival with ≥10 years of follow-up. The primary endpoint was all-cause mortality at maximum follow-up (median 11.9 years) assessed in the as-treated population. Of the 1743 patients, 901 (51.7%) underwent PCI, 532 (30.5%) received SAG, and 310 (17.8%) had MAG. At maximum follow-up, all-cause death occurred in 305 (33.9%), 175 (32.9%), and 70 (22.6%) patients in the PCI, SAG, and MAG groups, respectively (P < 0.001). Multiple arterial grafting [adjusted hazard ratio (HR) 0.66, 95% confidence interval (CI) 0.49-0.89], but not SAG (adjusted HR 0.83, 95% CI 0.67-1.03), was associated with significantly lower all-cause mortality compared with PCI. In patients with 3VD, both MAG (adjusted HR 0.55, 95% CI 0.37-0.81) and SAG (adjusted HR 0.68, 95% CI 0.50-0.91) were associated with significantly lower mortality than PCI, whereas in LMCAD patients, no significant differences between PCI and MAG (adjusted HR 0.90, 95% CI 0.56-1.46) or SAG (adjusted HR 1.11, 95% CI 0.81-1.53) were observed. In patients with revascularization of all three major myocardial territories, a positive correlation was observed between the number of myocardial territories receiving arterial grafts and survival (Ptrend = 0.003). CONCLUSION: Our findings suggest that MAG might be the more desirable configuration for CABG to achieve lower long-term all-cause mortality than PCI in patients with 3VD and/or LMCAD. TRIAL REGISTRATION: Registered on clinicaltrial.gov. SYNTAXES: NCT03417050 (https://clinicaltrials.gov/ct2/show/NCT03417050); SYNTAX: NCT00114972 (https://www.clinicaltrials.gov/ct2/show/NCT00114972).

Five-year outcomes after state-of-the-art percutaneous coronary revascularization in patients with de novo three-vessel disease: final results of the SYNTAX II study.

AIMS: The SYNTAX II study evaluated the impact of advances in percutaneous coronary intervention (PCI), integrated into a single revascularization strategy, on outcomes of patients with de novo three-vessel disease. The study employed decision-making utilizing the SYNTAX score II, use of coronary physiology, thin-strut biodegradable polymer drug-eluting stents, intravascular ultrasound, enhanced treatments of chronic total occlusions, and optimized medical therapy. Patients treated with this approach were compared with predefined patients from the SYNTAX I trial. METHODS AND RESULTS: SYNTAX II was a multicentre, single-arm, open-label study of patients requiring revascularization who demonstrated clinical equipoise for treatment with either coronary artery bypass grafting (CABG) or PCI, predicted by the SYNTAX score II. The primary endpoint was major adverse cardiac and cerebrovascular events (MACCE), which included any revascularization. The comparators were a matched PCI cohort trial and a matched CABG cohort, both from the SYNTAX I trial. At 5 years, MACCE rate in SYNTAX II was significantly lower than in the SYNTAX I PCI cohort (21.5% vs. 36.4%, P < 0.001). This reflected lower rates of revascularization (13.8% vs. 23.8%, P < 0.001), and myocardial infarction (MI) (2.7% vs. 10.4%, P < 0.001), consisting of both procedural MI (0.2% vs. 3.8%, P < 0.001) and spontaneous MI (2.3% vs. 6.9%, P = 0.004). All-cause mortality was lower in SYNTAX II (8.1% vs. 13.8%, P = 0.013) reflecting a lower rate of cardiac death (2.8% vs. 8.4%, P < 0.001). Major adverse cardiac and cerebrovascular events' outcomes at 5 years among patients in SYNTAX II and predefined patients in the SYNTAX I CABG cohort were similar (21.5% vs. 24.6%, P = 0.35). CONCLUSIONS: Use of the SYNTAX II PCI strategy in patients with de novo three-vessel disease led to improved and durable clinical results when compared to predefined patients treated with PCI in the original SYNTAX I trial. A predefined exploratory analysis found no significant difference in MACCE between SYNTAX II PCI and matched SYNTAX I CABG patients at 5-year follow-up.

The Use of Intraoperative Transit Time Flow Measurement for Coronary Artery Bypass Surgery: Systematic Review of the Evidence and Expert Opinion Statements.

Transit time flow measurement (TTFM) allows quality control in coronary artery bypass grafting but remains largely underused, probably because of limited information and the lack of standardization. We performed a systematic review of the evidence on TTFM and other methods for quality control in coronary artery bypass grafting following PRISMA standards and elaborated expert recommendations by using a structured process. A panel of 19 experts took part in the consensus process using a 3-step modified Delphi method that consisted of 2 rounds of electronic voting and a final face-to-face virtual meeting. Eighty percent agreement was required for acceptance of the statements. A 2-level scale (strong, moderate) was used to grade the statements based on the perceived likelihood of a clinical benefit. The existing evidence supports an association between TTFM readings and graft patency and postoperative clinical outcomes, although there is high methodological heterogeneity among the published series. The evidence is more robust for arterial, rather than venous, grafts and for grafts to the left anterior descending artery. Although TTFM use increases the duration and the cost of surgery, there are no data to quantify this effect. Based on the systematic review, 10 expert statements for TTFM use in clinical practice were formulated. Six were approved at the first round of voting, 3 at the second round, and 1 at the virtual meeting. In conclusion, although TTFM use may increase the costs and duration of the procedure and requires a learning curve, its cost/benefit ratio seems largely favorable, in view of the potential clinical consequences of graft dysfunction. These consensus statements will help to standardize the use of TTFM in clinical practice and provide guidance in clinical decision-making.

FAK promotes stromal PD-L2 expression associated with poor survival in pancreatic cancer.

BACKGROUND: Pancreatic Cancer is one of the most lethal cancers, with less than 8% of patients surviving 5 years following diagnosis. The last 40 years have seen only small incremental improvements in treatment options, highlighting the continued need to better define the cellular and molecular pathways contributing to therapy response and patient prognosis. METHODS: We combined CRISPR, shRNA and flow cytometry with mechanistic experiments using a KrasG12Dp53R172H mouse model of pancreatic cancer and analysis of publicly available human PDAC transcriptomic datasets. RESULTS: Here, we identify that expression of the immune checkpoint, Programmed Death Ligand 2 (PD-L2), is associated with poor prognosis, tumour grade, clinical stage and molecular subtype in patients with Pancreatic Ductal Adenocarcinoma (PDAC). We further show that PD-L2 is predominantly expressed in the stroma and, using an orthotopic murine model of PDAC, identify cancer cell-intrinsic Focal Adhesion Kinase (FAK) signalling as a regulator of PD-L2 stromal expression. Mechanistically, we find that FAK regulates interleukin-6, which can act in concert with interleukin-4 secreted by CD4 T-cells to drive elevated expression of PD-L2 on tumour-associated macrophages, dendritic cells and endothelial cells. CONCLUSIONS: These findings identify further complex heterocellular signalling networks contributing to FAK-mediated immune suppression in pancreatic cancer.

Bilateral versus Single Internal-Thoracic-Artery Grafts at 10 Years.

BACKGROUND: Multiple arterial grafts may result in longer survival than single arterial grafts after coronary-artery bypass grafting (CABG) surgery. We evaluated the use of bilateral internal-thoracic-artery grafts for CABG. METHODS: We randomly assigned patients scheduled for CABG to undergo bilateral or single internal-thoracic-artery grafting. Additional arterial or vein grafts were used as indicated. The primary outcome was death from any cause at 10 years. The composite of death from any cause, myocardial infarction, or stroke was a secondary outcome. RESULTS: A total of 1548 patients were randomly assigned to undergo bilateral internal-thoracic-artery grafting (the bilateral-graft group) and 1554 to undergo single internal-thoracic-artery grafting (the single-graft group). In the bilateral-graft group, 13.9% of the patients received only a single internal-thoracic-artery graft, and in the single-graft group, 21.8% of the patients also received a radial-artery graft. Vital status was not known for 2.3% of the patients at 10 years. In the intention-to-treat analysis at 10 years, there were 315 deaths (20.3% of the patients) in the bilateral-graft group and 329 deaths (21.2%) in the single-graft group (hazard ratio, 0.96; 95% confidence interval [CI], 0.82 to 1.12; P=0.62). Regarding the composite outcome of death, myocardial infarction, or stroke, there were 385 patients (24.9%) with an event in the bilateral-graft group and 425 patients (27.3%) with an event in the single-graft group (hazard ratio, 0.90; 95% CI, 0.79 to 1.03). CONCLUSIONS: Among patients who were scheduled for CABG and had been randomly assigned to undergo bilateral or single internal-thoracic-artery grafting, there was no significant between-group difference in the rate of death from any cause at 10 years in the intention-to-treat analysis. Further studies are needed to determine whether multiple arterial grafts provide better outcomes than a single internal-thoracic-artery graft. (Funded by the British Heath Foundation and others; Current Controlled Trials number, ISRCTN46552265 .).

Scaling at different ontogenetic stages: Gastrointestinal tract contents of a marsupial foregut fermenter, the western grey kangaroo Macropus fuliginosus melanops.

Prominent ontogenetic changes of the gastrointestinal tract (GIT) should occur in mammals whose neonatal diet of milk differs from that of adults, and especially in herbivores (as vegetation is particularly distinct from milk), and even more so in foregut fermenters, whose forestomach only becomes functionally relevant with vegetation intake. Due to the protracted lactation in marsupials, ontogenetic differences can be particularly well investigated in this group. Here, we report body mass (BM) scaling relationships of wet GIT content mass in 28 in-pouch young (50 g to 3 kg) and 15 adult (16-70 kg) western grey kangaroos Macropus fuliginosus melanops. Apart from the small intestinal contents, in-pouch young and adults did not differ in the scaling exponents ('slope' in log-log plots) but did differ in the scaling factor ('intercept'), with an implied substantial increase in wet GIT content mass during the out-of-pouch juvenile period. In contrast to forestomach contents, caecum contents were elevated in juveniles still in the pouch, suggestive of fermentative digestion of milk and intestinal secretion residues, particularly in the caecum. The substantial increase in GIT contents (from less than 1 to 10-20% of BM) was associated mainly with the increase in forestomach contents (from 25 to 80% of total GIT contents) and a concomitant decrease in small intestine contents (from 50 to 8%), emphasizing the shifting relevance of auto-enzymatic and allo-enzymatic (microbial) digestion. There was a concomitant increase in the contents-to-tissue ratio of the fermentation chambers (forestomach and caecum), but this ratio generally did not change for the small intestine. Our study not only documents significant ontogenetic changes in digestive morpho-physiology, but also exemplifies the usefulness of intraspecific allometric analyses for quantifying these changes.

Sex differences in outcomes after coronary artery bypass grafting: a pooled analysis of individual patient data.

AIMS: Data suggest that women have worse outcomes than men after coronary artery bypass grafting (CABG), but results have been inconsistent across studies. Due to the large differences in baseline characteristics between sexes, suboptimal risk adjustment due to low-quality data may be the reason for the observed differences. To overcome this limitation, we undertook a systematic review and pooled analysis of high-quality individual patient data from large CABG trials to compare the adjusted outcomes of women and men. METHODS AND RESULTS: The primary outcome was a composite of all-cause mortality, myocardial infarction (MI), stroke, and repeat revascularization (major adverse cardiac and cerebrovascular events, MACCE). The secondary outcome was all-cause mortality. Multivariable mixed-effect Cox regression was used. Four trials involving 13 193 patients (10 479 males; 2714 females) were included. Over 5 years of follow-up, women had a significantly higher risk of MACCE [adjusted hazard ratio (HR) 1.12, 95% confidence interval (CI) 1.04-1.21; P = 0.004] but similar mortality (adjusted HR 1.03, 95% CI 0.94-1.14; P = 0.51) compared to men. Women had higher incidence of MI (adjusted HR 1.30, 95% CI 1.11-1.52) and repeat revascularization (adjusted HR 1.22, 95% CI 1.04-1.43) but not stroke (adjusted HR 1.17, 95% CI 0.90-1.52). The difference in MACCE between sexes was not significant in patients 75 years and older. The use of off-pump surgery and multiple arterial grafting did not modify the difference between sexes. CONCLUSIONS: Women have worse outcomes than men in the first 5 years after CABG. This difference is not significant in patients aged over 75 years and is not affected by the surgical technique.

Postoperative Atrial Fibrillation and Long-Term Risk of Stroke After Isolated Coronary Artery Bypass Graft Surgery.

BACKGROUND: Postoperative atrial fibrillation (pAF) after coronary artery bypass grafting is a common complication. Whether pAF is associated with an increased risk of cerebrovascular accident (CVA) remains uncertain. We investigated the association between pAF and long-term risk of CVA by performing a post hoc analysis of 10-year outcomes of the ART (Arterial Revascularization Trial). METHODS: For the present analysis, among patients enrolled in the ART (n=3102), we excluded those who did not undergo surgery (n=25), had a history of atrial fibrillation (n=45), or had no information on the incidence of pAF (n=9). The final population consisted of 3023 patients, of whom 734 (24.3%) developed pAF with the remaining 2289 maintaining sinus rhythm. Competing risk and Cox regression analyses were used to investigate the association between pAF and the risk of CVA. RESULTS: At 10 years, the cumulative incidence of CVA was 6.3% (4.6%-8.1%) versus 3.7% (2.9%-4.5%) in patients with pAF and sinus rhythm, respectively. pAF was an independent predictor of CVA at 10 years (hazard ratio, 1.53 [95% CI, 1.06-2.23]; P=0.025) even when CVAs that occurred during the index admission were excluded from the analysis (hazard ratio, 1.47 [95% 1.02-2.11]; P=0.04). CONCLUSIONS: Patients with pAF after coronary artery bypass grafting are at higher risk of CVA. These findings challenge the notion that pAF is a benign complication.

Radial-Artery or Saphenous-Vein Grafts in Coronary-Artery Bypass Surgery.

BACKGROUND: The use of radial-artery grafts for coronary-artery bypass grafting (CABG) may result in better postoperative outcomes than the use of saphenous-vein grafts. However, randomized, controlled trials comparing radial-artery grafts and saphenous-vein grafts have been individually underpowered to detect differences in clinical outcomes. We performed a patient-level combined analysis of randomized, controlled trials to compare radial-artery grafts and saphenous-vein grafts for CABG. METHODS: Six trials were identified. The primary outcome was a composite of death, myocardial infarction, or repeat revascularization. The secondary outcome was graft patency on follow-up angiography. Mixed-effects Cox regression models were used to estimate the treatment effect on the outcomes. RESULTS: A total of 1036 patients were included in the analysis (534 patients with radial-artery grafts and 502 patients with saphenous-vein grafts). After a mean (±SD) follow-up time of 60±30 months, the incidence of adverse cardiac events was significantly lower in association with radial-artery grafts than with saphenous-vein grafts (hazard ratio, 0.67; 95% confidence interval [CI], 0.49 to 0.90; P=0.01). At follow-up angiography (mean follow-up, 50±30 months), the use of radial-artery grafts was also associated with a significantly lower risk of occlusion (hazard ratio, 0.44; 95% CI, 0.28 to 0.70; P<0.001). As compared with the use of saphenous-vein grafts, the use of radial-artery grafts was associated with a nominally lower incidence of myocardial infarction (hazard ratio, 0.72; 95% CI, 0.53 to 0.99; P=0.04) and a lower incidence of repeat revascularization (hazard ratio, 0.50; 95% CI, 0.40 to 0.63; P<0.001) but not a lower incidence of death from any cause (hazard ratio, 0.90; 95% CI, 0.59 to 1.41; P=0.68). CONCLUSIONS: As compared with the use of saphenous-vein grafts, the use of radial-artery grafts for CABG resulted in a lower rate of adverse cardiac events and a higher rate of patency at 5 years of follow-up. (Funded by Weill Cornell Medicine and others.).

Anti-PD-1/anti-CTLA-4 efficacy in melanoma brain metastases depends on extracranial disease and augmentation of CD8+ T cell trafficking.

Inhibition of immune checkpoints programmed death 1 (PD-1) and cytotoxic T lymphocyte-associated protein 4 (CTLA-4) on T cells results in durable antitumor activity in melanoma patients. Despite high frequency of melanoma brain metastases (BrM) and associated poor prognosis, the activity and mechanisms of immune checkpoint inhibitors (ICI) in metastatic tumors that develop within the "immune specialized" brain microenvironment, remain elusive. We established a melanoma tumor transplantation model with intracranial plus extracranial (subcutaneous) tumor, mimicking the clinically observed coexistence of metastases inside and outside the brain. Strikingly, intracranial ICI efficacy was observed only when extracranial tumor was present. Extracranial tumor was also required for ICI-induced increase in CD8+ T cells, macrophages, and microglia in brain tumors, and for up-regulation of immune-regulatory genes. Combined PD-1/CTLA-4 blockade had a superior intracranial efficacy over the two monotherapies. Cell depletion studies revealed that NK cells and CD8+ T cells were required for intracranial anti-PD-1/anti-CTLA-4 efficacy. Rather than enhancing CD8+ T cell activation and expansion within intracranial tumors, PD-1/CTLA-4 blockade dramatically (∼14-fold) increased the trafficking of CD8+ T cells to the brain. This was mainly through the peripheral expansion of homing-competent effector CD8+ T cells and potentially further enhanced through up-regulation of T cell entry receptors intercellular adhesion molecule 1 and vascular adhesion molecule 1 on tumor vasculature. Our study indicates that extracranial activation/release of CD8+ T cells from PD-1/CTLA-4 inhibition and potentiation of their recruitment to the brain are paramount to the intracranial anti-PD-1/anti-CTLA-4 activity, suggesting augmentation of these processes as an immune therapy-enhancing strategy in metastatic brain cancer.

Arterial Grafts for Coronary Bypass: A Critical Review After the Publication of ART and RADIAL.

Observational and randomized evidence shows that arterial grafts have better patency rates than saphenous vein grafts (SVGs) in coronary artery bypass grafting. Observational studies suggest that the use of multiple arterial grafts is associated with longer postoperative survival, but this must be interpreted in the context of treatment allocation bias and hidden confounders intrinsic to the study designs. Recently, a pooled analysis of 6 randomized trials comparing the radial artery with the SVG as the second conduit and the largest randomized trial comparing the use of single and bilateral internal thoracic arteries have provided apparently divergent results about a clinical benefit with the use of >1 arterial conduit. However, both analyses have methodological limitations that may have influenced their results. At present, it is unclear whether the well-documented increased patency rate of arterial grafts translates into clinical benefits in the majority of patients undergoing coronary artery bypass grafting. A large randomized trial testing the arterial grafts hypothesis (ROMA [Randomized Comparison of the Clinical Outcome of Single Versus Multiple Arterial Grafts]) is underway and will report the results in a few years.

Sex-related differences in outcomes after coronary artery bypass surgery-A patient-level pooled analysis of randomized controlled trials: rationale and study protocol.

INTRODUCTION: The impact of sex on the outcomes after coronary artery bypass grafting (CABG) is controversial. The majority of CABG studies are retrospectively collected clinical or registry data, women comprise only a minority, and the reported findings represent the male predominated cohort. This individual patient meta-analysis is aimed at evaluating sex-related differences in outcomes after CABG using high quality data from randomized controlled trials (RCTs). METHODS AND ANALYSIS: A systematic literature search will be performed to identify all CABG RCTs (minimum follow-up: 5 years). Detailed specification for the minimum deidentified patient records' data requirements will be provided to RCT primary contact to request their deidentified data for pooling. The pooled analysis will follow the prospective register of systematic reviews (PROSPERO) and the preferred reporting items for systematic reviews and meta-analyses for individual patient data systematic reviews (PRISMA-IPD) recommendations and will compare sex-related outcomes after CABG. The main hypothesis is that outcomes after CABG are worse in women than in men. We will also test whether treatment effects for off-pump and the use of multiple arterial grafts are present within each sex, and also, whether there are differential treatment effects between sexes. The primary endpoint will be a composite of all-cause mortality, myocardial infarction, stroke, and repeat revascularization at long-term follow up. ETHICS AND DISSEMINATION: Ethics approval and participant consent for the study will be obtained locally by each study team if needed. Data will be disseminated and submitted to peer-reviewed scientific journals and meetings irrespective of study outcome.

Impact of large periprocedural myocardial infarction on mortality after percutaneous coronary intervention and coronary artery bypass grafting for left main disease: an analysis from the EXCEL trial.

AIMS: The prognostic implications of periprocedural myocardial infarction (PMI) after percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) remain controversial. We examined the 3-year rates of mortality among patients with and without PMI undergoing left main coronary artery intervention randomized to PCI with everolimus-eluting stents vs. CABG in the large-scale, multicentre, prospective, randomized EXCEL trial. METHODS AND RESULTS: By protocol, PMI was defined using an identical threshold for PCI and CABG [creatinine kinase-MB (CK-MB) elevation >10× the upper reference limit (URL) within 72 h post-procedure, or >5× URL with new Q-waves, angiographic vessel occlusion, or loss of myocardium on imaging]. Cox proportional hazards modelling was performed controlling for age, sex, hypertension, diabetes mellitus, left ventricular ejection fraction, SYNTAX score, and chronic obstructive pulmonary disease (COPD). A total of 1858 patients were treated as assigned by randomization. Periprocedural MI occurred in 34/935 (3.6%) of patients in the PCI group and 56/923 (6.1%) of patients in the CABG group [odds ratio 0.61, 95% confidence interval (CI) 0.40-0.93; P = 0.02]. Periprocedural MI was associated with SYNTAX score, COPD, cross-clamp duration and total procedure duration, and not using antegrade cardioplegia. By multivariable analysis, PMI was associated with cardiovascular death and all-cause death at 3 years [adjusted hazard ratio (HR) 2.63, 95% CI 1.19-5.81; P = 0.02 and adjusted HR 2.28, 95% CI 1.22-4.29; P = 0.01, respectively]. The effect of PMI was consistent for PCI and CABG for cardiovascular death (Pinteraction = 0.56) and all-cause death (Pinteraction = 0.59). Peak post-procedure CK-MB ≥10× URL strongly predicted mortality, whereas lesser degrees of myonecrosis were not associated with prognosis. CONCLUSION: In the EXCEL trial, PMI was more common after CABG than PCI, and was strongly associated with increased 3-year mortality after controlling for potential confounders. Only extensive myonecrosis (CK-MB ≥10× URL) was prognostically important.

Association of Radial Artery Graft vs Saphenous Vein Graft With Long-term Cardiovascular Outcomes Among Patients Undergoing Coronary Artery Bypass Grafting: A Systematic Review and Meta-analysis.

Importance: Observational studies have suggested that the use of radial artery grafts for coronary artery bypass grafting may improve clinical outcomes compared with the use of saphenous vein grafts, but this has not been confirmed in randomized trials. Objective: To compare clinical outcomes between patients receiving radial artery vs saphenous vein grafts for coronary artery bypass grafting after long-term follow-up. Design, Setting, and Participants: Patient-level pooled analysis comparing radial artery vs saphenous vein graft in adult patients undergoing isolated coronary artery bypass grafting from 5 countries (Australia, Italy, Serbia, South Korea, and the United Kingdom), with enrollment from 1997 to 2009 and follow-up completed in 2019. Interventions: Patients were randomized to undergo either radial artery (n = 534) or saphenous vein (n = 502) grafts for coronary artery bypass grafting. Main Outcomes and Measures: The primary outcome was a composite of death, myocardial infarction, or repeat revascularization and the secondary outcome was a composite of death or myocardial infarction. Results: A total of 1036 patients were randomized (mean age, 66.6 years in the radial artery group vs 67.1 years in the saphenous vein group; 376 [70.4%] men in the radial artery group vs 351 [69.9%] in the saphenous vein group); 942 (90.9%) of the originally randomized patients completed 10 years of follow-up (510 in the radial artery group). At a median (interquartile range) follow-up of 10 (10-11) years, the use of the radial artery, compared with the saphenous vein, in coronary artery bypass grafting was associated with a statistically significant reduction in the incidence of the composite outcome of death, myocardial infarction, or repeat revascularization (220 vs 237 total events; 41 vs 47 events per 1000 patient-years; hazard ratio, 0.73 [95% CI, 0.61-0.88]; P < .001) and of the composite of death or myocardial infarction (188 vs 193 total events; 35 vs 38 events per 1000 patient-years; hazard ratio, 0.77 [95% CI, 0.63-0.94]; P = .01). Conclusions and Relevance: In this individual participant data meta-analysis with a median follow-up of 10 years, among patients undergoing coronary artery bypass grafting, the use of the radial artery compared with the saphenous vein was associated with a lower risk of a composite of cardiovascular outcomes.

SERUM BIOCHEMISTRY OF FREE-RANGING SOUTHERN HAIRY-NOSED WOMBATS (LASIORHINUS LATIFRONS).

Listed as near-threatened by the International Union for Conservation of Nature (IUCN), the southern hairy-nosed wombat (SHNW, Lasiorhinus latifrons) faces threats such as drought, habitat degradation and loss, disease, and persecution because of competition with agriculture. To assist with evaluation of wombat health, this study reports serum biochemical reference intervals (RIs) for wild-caught SHNW from South Australia established from 126 apparently healthy SHNW using a Beckman Coulter AU480® Automated Chemistry Analyzer using RefVal Advisor. Partitioning of RIs for male and female wombats and for the two methods of sampling was performed as appropriate, and additional significant differences (P < 0.05) in biochemical profiles were identified across age class and season examined. A number of differences were observed between male and female wombats, most notably higher creatinine, urea, and sodium in females. Subadult and juvenile wombats had significantly lower total protein, globulin, and ALT activity, and significantly higher ALP activity than adults. Wombats sampled in winter and spring had significantly higher total protein, albumin, potassium, bicarbonate, and enzyme activities (ALP, ALT, AST, GGT, GLDH, lipase), and significantly lower glucose and creatinine when compared to individuals sampled in summer and autumn. Differences in CK activity and anion gap observed between the two methods of sampling likely reflect delay and handling of animals between capture and blood collection. The serum biochemical RIs documented here are considered representative of a population of healthy SHNW, providing a tool for health assessment and monitoring of SHNW health in South Australia and elsewhere.

Myocardial Revascularization Trials.

This article reviews the context and evidence of recent myocardial revascularization trials that compared percutaneous coronary intervention with coronary artery bypass grafting for the treatment of left main and multivessel coronary artery disease. We develop the rationale that some of the knowledge synthesis resulting from these trials, particularly with regard to the claimed noninferiority of percutaneous coronary intervention beyond nondiabetic patients with low anatomic complexity, may have been affected by trial design, patient selection based on suitability for percutaneous coronary intervention, and end point optimization favoring percutaneous coronary intervention over coronary artery bypass grafting. We provide recommendations that include holding a circumspect interpretation of the currently available evidence, as well as suggestions for the collaborative design and conduct of future clinical trials in this and other fields.

New Strategies for Surgical Myocardial Revascularization.

We summarize the evidence on the new strategies for coronary artery bypass grafting (CABG). Hybrid CABG implies surgical grafting of the left anterior descending artery and percutaneous treatment of the other target vessels, with the promise of combining the durable benefits of surgery with the less invasive approach of percutaneous coronary interventions. Robotic CABG and minimally invasive CABG are performed through minimal incision or port access with dedicated equipment and instruments. Anaortic coronary artery bypass refers to off-pump CABG using only in-situ grafts. The use of multiple arterial grafts has been shown to improve patency and is potentially associated with better clinical outcomes. All these techniques require dedicated training and are more complex than conventional CABG but can significantly improve the results of surgery. Validation of the results of these new approaches in large randomized trials is a priority for the surgical community.

B-Type Natriuretic Peptide Assessment in Patients Undergoing Revascularization for Left Main Coronary Artery Disease: Analysis From the EXCEL Trial.

BACKGROUND: Elevated B-type natriuretic peptide (BNP) is reflective of impaired cardiac function and is associated with worse prognosis among patients with coronary artery disease (CAD). We sought to assess the association between baseline BNP, adverse outcomes, and the relative efficacy of percutaneous coronary intervention (PCI) versus coronary artery bypass grafting (CABG) in patients with left main CAD. METHODS: The EXCEL trial (Evaluation of XIENCE Versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization) randomized patients with left main CAD and low or intermediate SYNTAX scores (Synergy Between PCI With TAXUS and Cardiac Surgery) to PCI with everolimus-eluting stents versus CABG. The primary end point was the composite of all-cause death, myocardial infarction, or stroke. We used multivariable Cox proportional hazards regression to assess the associations between normal versus elevated BNP (≥100 pg/mL), randomized treatment, and the 3-year risk of adverse events. RESULTS: BNP at baseline was elevated in 410 of 1037 (39.5%) patients enrolled in EXCEL. Patients with elevated BNP levels were older and more frequently had additional cardiovascular risk factors and lower left ventricular ejection fraction than those with normal BNP, but had similar SYNTAX scores. Patients with elevated BNP had significantly higher 3-year rates of the primary end point (18.6% versus 11.7%; adjusted hazard ratio [HR], 1.62; 95% confidence interval [CI], 1.16-2.28; P=0.005) and higher mortality (11.5% versus 3.9%; adjusted HR, 2.49; 95% CI, 1.48-4.19; P=0.0006), both from cardiovascular and noncardiovascular causes. In contrast, there were no significant differences in the risks of myocardial infarction, stroke, ischemia-driven revascularization, stent thrombosis, graft occlusion, or major bleeding. A significant interaction ( Pinteraction=0.03) was present between elevated versus normal BNP and treatment with PCI versus CABG for the adjusted risk of the primary composite end point at 3 years among patients with elevated BNP (adjusted HR for PCI versus CABG, 1.54; 95% CI, 0.96-2.47) versus normal BNP (adjusted HR, 0.74; 95% CI, 0.46-1.20). This interaction was stronger when log(BNP) was modeled as a continuous variable ( Pinteraction=0.002). CONCLUSIONS: In the EXCEL trial, elevated baseline BNP levels in patients with left main CAD undergoing revascularization were independently associated with long-term mortality but not nonfatal adverse ischemic or bleeding events. The relative long-term outcomes after PCI versus CABG for revascularization of left main CAD may be conditioned by the baseline BNP level. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT01205776.