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Background: In patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI), selecting an antithrombotic regimen requires balancing risks of ischemic cardiac events, stroke, and bleeding., Methods: We studied 467 patients with AF undergoing PCI in the time period from December 2015 to July 2018 identified via a chart audit by 47 Canadian cardiologists in the CONNECT AF+PCI (the Co ordinated N ational N etwork to E ngage Interventional C ardiologists in the Antithrombotic T reatment of Patients With A trial F ibrillation Undergoing P ercutaneous C oronary I ntervention) study, to determine patterns of initial antithrombotic therapy selection., Results: The median (25th, 75th percentile) CHADS 2 score was 2 (1, 3), and PCI was performed in the setting of acute coronary syndrome in 62.1%. Triple antithrombotic therapy (TAT) was the initial treatment in 62.7%, dual-pathway therapy in 25.7%, and dual antiplatelet therapy in 11.6%, with a temporal increase in use of dual-pathway therapy during the course of the study; median intended TAT duration was 1 (1, 3) month. Compared with patients selected for TAT, patients selected for dual-pathway therapy were less likely to have prior myocardial infarction (35.8% vs 25.8%, P  = 0.045) and prior PCI (33.8% vs 23.3%, P  = 0.03), and they received shorter total length of stents (38 [23, 56] vs 30 [20, 46] mm, P  = 0.03). Patients selected for dual-pathway therapy had a higher prevalence of prior stroke/transient ischemic attack (13.0% vs 23.3%, P  = 0.01). There was no difference in prevalence of anemia (21.5% vs 25.8%, P  = 0.30). Use of dual-pathway therapy was similar among patients with acute coronary syndrome and those with stable disease (24.1% vs 28.2%, P  = 0.32)., Conclusions: Approximately one-quarter of AF patients undergoing PCI are treated with dual-pathway therapy in Canadian practice, with its use increasing during the studied period. Patients selected for dual-pathway therapy have less-complex coronary disease history and intervention., (© 2021 The Authors.)

In this work, we use the transfer matrix method to optimize TPBi capping layers deposited on organic light emitting diodes with respect to light extraction and transmittance. The green transparent organic light emitting diodes comprise three organic semiconductors (CBP, Ir(ppy)₃ and TPBi) forming an efficient simplified phosphorescent organic light emitting diode stack. A transparent cathode of 2 nm Cs₂CO₃, 2 nm Al and 16 nm Au is deposited by thermal evaporation. The diode stack as well as the capping layer are deposited by organic vapor phase deposition. The refractive indices and extinction coefficients of all materials in the transparent organic light emitting diodes (glass, indium tin oxide, organic semiconductors and cathode) are determined using spectroscopic ellipsometry combined with optical transmittance and reflectance measurements. With these spectrally resolved data, we calculate the transmittance of transparent organic light emitting diodes with TPBi capping layers of different thicknesses. The results were validated with high accuracy in the visible spectral range and beyond (360 nm-1000 nm) by a series of experiments. By choosing a TPBi capping layer of optimized thickness (here 50 nm), we fabricated transparent organic light emitting diodes with an optical transmittance which was strongly enhanced from 47% (reference without capping layer) to 65%, measured at 555 nm.

Background: Revascularization in patients with chronic kidney disease (CKD) and coronary artery disease (CAD) is often deferred because of concern over progression of renal failure., Hypothesis: Revascularization with either coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) leads to progression of renal failure, but improves survival compared with medical therapy in patients with CKD., Patients and Methods: Linkages between the British Columbia Cardiac Registry and the British Columbia Renal Registry of patients with established CAD and CKD who underwent CABG, PCI, or were treated medically were propensity matched. Overall patient survival was analyzed using a Cox proportional hazard model. Primary renal outcomes, defined as patients requiring long-term dialysis or progressive loss in kidney function, were analyzed using a competing risk approach., Results: On the basis of the matched cohort, the risk of renal outcome in the first three months was the highest in the CABG group, but comparable between the PCI and the medical group (estimated probability at 3 months: 12.7% for CABG, 5.4% for PCI, 4.4% for medical; P<0.01). The estimated probability for the renal outcome at 24 months was similar across the groups: 37.9% for CABG, 37.6% for PCI, and 35.2% for medical therapy (P=0.62). The mortality risk at 24 months was lower for CABG (3.9%) compared with PCI (14.5%) or medical therapy (16.4%) (P<0.01)., Conclusion: In patients with CAD and CKD who undergo the current practice of CABG, PCI, or are treated with medical therapy, progression of renal failure is higher in the first 3 months for CABG, but similar for all groups at 24 months. The 2-year mortality is lower in patients treated with CABG compared with PCI or medical therapy.

Background: Little is known on whether there are ethnic differences in outcomes following percutaneous coronary intervention (PCI) and coronary artery bypass grafting surgery (CABG) after acute myocardial infarction (AMI). We compared 30-day and long-term mortality, recurrent AMI, and congestive heart failure in South Asian, Chinese and White patients with AMI who underwent PCI and CABG., Methods: Hospital administrative data in British Columbia (BC), Canada were linked to the BC Cardiac Registry to identify all patients with AMI who underwent PCI (n = 4729) or CABG (n = 1687) (1999-2003). Ethnicity was determined from validated surname algorithms. Logistic regression for 30-day mortality and Cox proportional-hazards models were adjusted for age, sex, socio-economic status, severity of coronary disease, comorbid conditions, time from AMI to a revascularization procedure and distance to the nearest hospital., Results: Following PCI, Chinese had higher short-term mortality (Odds Ratio (OR): 2.36, 95% CI: 1.12-5.00; p = 0.02), and South Asians had a higher risk for recurrent AMI (OR: 1.34, 95% CI: 1.08-1.67, p = 0.007) and heart failure (OR 1.81, 95% CI: 1.00-3.29, p = 0.05) compared to White patients. Risk of heart failure was higher in South Asian patients who underwent CABG compared to White patients (OR (95% CI) = 2.06 (0.92-4.61), p = 0.08). There were no significant differences in mortality following CABG between groups., Conclusions: Chinese and South Asian patients with AMI and PCI or CABG had worse outcomes compared to their White counterparts. Further studies are needed to confirm these findings and investigate potential underlying causes.

Background: Bleeding following percutaneous coronary intervention (PCI) is common and may lead to transfusion and death. Although previous work has examined the effect of red blood cell (RBC) transfusion in patients with coronary disease, no study had investigated whether transfusion of non-RBC components was associated with mortality following PCI., Methods: All subjects transfused in the 10 days following PCI were identified using the British Columbia Cardiac and Central Transfusion Registries. Patients undergoing cardiac surgery following PCI were excluded as transfusion was assumed to be due to surgical related bleeding. Transfusion products were categorised as RBC and non-RBC comprising platelets, plasma and cryoprecipitate. Blood product use was compared according to thirty day mortality using multivariate regression and propensity adjustment for confounding variables., Results: From a total of 32,580 patients who underwent PCI, 952 patients received at least 1 blood product within 10 days of PCI. Non-RBC transfusion occurred more commonly in the cohort of transfused patients dying within 30 days (p<0.001). After adjustment for baseline risk, transfusion of plasma/cryoprecipitate (HR 5.17; 95% C.I. 2.87-9.32, p<0.001) and platelets (HR 2.13; 95% C.I. 1.10-4.13, p=0.03) was associated with increased 30 day mortality. In a propensity risk adjusted model, transfusion of plasma/cryoprecipitate and RBC transfusion volume remained as significant predictors of 30-day mortality (p<0.001)., Conclusions: Transfusion following PCI appears to be associated with an increased risk of death within 30 days. We now report that transfusion with plasma rich non-RBC products may confer an additional mortality risk to patients undergoing PCI., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Background: Blood transfusion has been associated with an increased mortality in patients undergoing percutaneous coronary intervention (PCI). Although the reasons for this remain unclear, it may be related to the structural and functional changes occurring within red blood cells (RBCs) during storage. We investigated whether RBC storage duration was associated with mortality in patients requiring transfusion after PCI., Methods: We collected data on all RBC transfusions occurring within 10 days of PCI (excluding those related to cardiac surgery) using the British Columbia Cardiac Registry and Central Transfusion Registry. Transfusion details were analyzed according to 30-day survival., Results: From a total of 32,580 patients undergoing PCI, 909 (2.8%) patients received RBCs with a mean storage duration of 25 +/- 10 days. In these 909 patients, mean transfusion volumes were lower in survivors (2.8 +/- 2.1 vs 3.8 +/- 2.9 U, P = .002) than those who died within 30 days. In a multivariate analysis to adjust for baseline risk, mean RBC storage age (HR 1.02 [95% CI 1.01-1.04], P = .002) and transfusion volume (HR 1.26 [95% CI 1.18-1.34], P < .001) both predicted 30-day mortality. Transfused patients who received only older blood (RBC min age >28 days) appeared to be at greater risk of death (HR 2.49 [95% CI 1.45-4.25], P = .001)., Conclusion: Red blood cell transfusion is associated with increased 30-day mortality in patients undergoing PCI. Although current transfusion practice permits RBC storage for up to 42 days, the use of older red cells may pose an additional hazard to this patient group., (2010 Mosby, Inc. All rights reserved.)

The effect of nitroprusside on pressure wave transmission from ascending aorta to radial artery was studied in 10 patients with severe congestive heart failure. Nitroprusside resulted in a beneficial increase in cardiac index, reduction of pulmonary wedge pressure and reductions of aortic and radial arterial mean pressures. In 6 patients with an identifiable late systolic peak of aortic pressure (group I), nitroprusside reduced aortic systolic pressure more than radial systolic pressure, resulting in an increase in the difference between aortic and radial systolic arterial pressure (group I control 13 +/- 4, nitroprusside 20 +/- 6 mm Hg; p less than 0.025). Yet in 4 patients in whom no aortic late systolic pressure wave was apparent (group II), nitroprusside did not alter the difference between aortic and radial systolic pressures. Radial arterial pressure is often used to estimate the effect of nitroprusside on the arterial pressure load on the left ventricle. These results indicate that a reduction of radial systolic pressure induced by nitroprusside may underestimate the true reduction of aortic systolic pressure and thus the effect of the vasodilator on the arterial load on the left ventricle. The enhanced difference between aortic and radial arterial systolic pressures appears to be the consequence of nitroprusside on arterial pressure reflections.

It has previously been shown that nitroglycerin increases the compliance of forearm arteries. The present study investigates whether nitroglycerin reduces the hydraulic load on the heart (as measured by aortic input impedance) by a mechanism compatible with an increase in peripheral arterial compliance. In eight subjects, measurements of aortic flow and pressure were made with a catheter tipped probe before and during intravenous nitroglycerin (6 to 30 micrograms/min) administration. The reduction of aortic systolic pressure (129 +/- 5 to 113 +/- 4 mmHg, P less than 0.001) was due to a decrease in the late systolic pressure peak. There was no change in stroke volume, heart rate or systemic vascular resistance. The lower systolic pressure resulted from a decrease in the amplitude of the first harmonic of input impedance (210 +/- 19 to 143 +/- 11 dyne.s.cm-5, P less than 0.005) yet characteristic impedance (a measure of local aortic distensibility) did not change. The ratio of maxima to minima of the impedance spectrum was reduced (1.02 +/- 0.09 to 0.71 +/- 0.11, P less than 0.05) suggesting a decrease in the amplitude of reflected waves contributing to aortic impedance. Nitroglycerin at doses which have no effect on arteriolar resistance vessels, reduces systolic aortic pressure by diminishing the amplitude of wave reflections returning to the ascending aorta in late systole. This mechanism is compatible with the peripheral arterial effects of nitroglycerin.