Pacemaker Implantation After Mitral Valve Surgery With Atrial Fibrillation Ablation.

BACKGROUND: The incidence of permanent pacemaker (PPM) implantation is higher following mitral valve surgery (MVS) with ablation for atrial fibrillation (AF) compared with MVS alone. OBJECTIVES: This study identified risk factors and outcomes associated with PPM implantation in a randomized trial that evaluated ablation for AF in patients who underwent MVS. METHODS: A total of 243 patients with AF and without previous PPM placement were randomly assigned to MVS alone (n = 117) or MVS + ablation (n = 126). Patients in the ablation group were further randomized to pulmonary vein isolation (PVI) (n = 62) or the biatrial maze procedure (n = 64). Using competing risk models, this study examined the association among PPM and baseline and operative risk factors, and the effect of PPM on time to discharge, readmissions, and 1-year mortality. RESULTS: Thirty-five patients received a PPM within the first year (14.4%), 29 (83%) underwent implantation during the index hospitalization. The frequency of PPM implantation was 7.7% in patients randomized to MVS alone, 16.1% in MVS + PVI, and 25% in MVS + biatrial maze. The indications for PPM were similar among patients who underwent MVS with and without ablation. Ablation, multivalve surgery, and New York Heart Association functional (NYHA) functional class III/IV were independent risk factors for PPM implantation. Length of stay post-surgery was longer in patients who received PPMs, but it was not significant when adjusted for randomization assignment (MVS vs. ablation) and age (hazard ratio [HR]: 0.81; 95% confidence interval [CI]: 0.61 to 1.08; p = 0.14). PPM implantation did not increase 30-day readmission rate (HR: 1.43; 95% CI: 0.50 to 4.05; p = 0.50). The need for PPM was associated with a higher risk of 1-year mortality (HR: 3.21; 95% CI: 1.01 to 10.17; p = 0.05) after adjustment for randomization assignment, age, and NYHA functional class. CONCLUSIONS: AF ablation, multivalve surgery, and NYHA functional class III/IV were associated with an increased risk for permanent pacing. PPM implantation following MVS was associated with a significant increase in 1-year mortality. (Surgical Ablation Versus No Surgical Ablation for Patients With Atrial Fibrillation Undergoing Mitral Valve Surgery; NCT00903370).

Eight-year follow-up of the Clopidogrel After Surgery for Coronary Artery Disease (CASCADE) trial.

OBJECTIVE: In this 8 years' follow-up study, we evaluated the long-term outcomes of the addition of clopidogrel to aspirin during the first year after coronary artery bypass grafting, versus aspirin plus placebo, with respect to survival, major adverse cardiac, or major cerebrovascular events, including revascularization, functional status, graft patency, and native coronary artery disease progression. METHODS: In the initial Clopidogrel After Surgery for Coronary Artery Disease trial, 113 patients were randomized to receive either daily clopidogrel (n = 56) or placebo (n = 57), in addition to aspirin, in a double-blind fashion for 1 year after coronary artery bypass grafting. All patients were re-evaluated to collect long-term clinical data. Surviving patients with a glomerular filtration rate > 30 mL/min were asked to undergo a coronary computed tomography angiogram to evaluate the late saphenous vein graft patency and native coronary artery disease progression. RESULTS: At a median follow-up of 7.6 years, survival rate was 85.5% ± 3.8% (P = .23 between the 2 groups). A trend toward enhanced freedom from all-cause death or major adverse cardiac or cerebrovascular events, including revascularization, was observed in the aspirin-clopidogrel group (P = .11). No difference in functional status or freedom from angina was observed between the 2 groups (P > .57). The long-term patency of saphenous vein graft was 89.11% in the aspirin-clopidogrel group versus 91.23% in the aspirin-placebo group (P = .79). A lower incidence of moderate to severe native disease progression was observed in the aspirin-clopidogrel group versus the aspirin-placebo group (7 out of 122 vs 13 out of 78 coronary segments that showed progression, respectively [odds ratio, 0.3 ± 0.2; 95% confidence interval, 0.1-0.8; P = .02]). CONCLUSIONS: At 8 years' follow-up, the addition of clopidogrel to aspirin during the first year after coronary artery bypass grafting exhibited a lower incidence of moderate to severe progression of native coronary artery disease and a trend toward higher freedom from major adverse cardiac or cerebrovascular events, including revascularization, or death in the aspirin-clopidogrel group. CLINICAL TRIAL REGISTRATION: http://www.clinicaltrials.gov. Unique identifier: NCT00228423.

One-pot synthesis of polyunsaturated fatty acid amides with anti-proliferative properties.

A one-pot environmentally friendly transamidation of ω-3 fatty acid ethyl esters to amides and mono- or diacylglycerols was investigated via the use of a polymer-supported lipase. The method was used to synthesize a library of fatty acid monoglyceryl esters and amides. These new derivatives were found to have potent growth inhibition effects against A549 lung cancer cells.

Elucidation of the structure-activity relationships of apelin: influence of unnatural amino acids on binding, signaling, and plasma stability.

Apelin is the endogenous ligand of the APJ receptor, a member of the G-protein-coupled receptor family. The apelin-APJ complex has been detected in many tissues and is emerging as a promising target for several pathophysiological conditions. There is currently little information on the structure-activity relationship (SAR) of the apelin hormone. In an effort to better delineate SAR, we synthesized analogues of apelin-13 modified at selected positions with unnatural amino acids, with a particular emphasis on the C-terminal portion. Analogues were then tested in binding and functional assays by evaluating Gi/o-mediated decreases in cAMP levels and by assessing ß-arrestin2 recruitment to the APJ receptor. The plasma stability of new compounds was also assessed. Several analogues were found to possess increased binding and higher stability than the parent peptide.

Role of acidic amino acid residues in chitooligosaccharide-binding to Streptomyces sp. N174 chitosanase.

We examined the oligosaccharide binding to Streptomyces sp. N174 chitosanase by fluorescence spectroscopy. By means of the tryptophan fluorescence quenching, the oligosaccharide binding abilities were evaluated using the three mutant enzymes (D57A, E197A, and D201A). The enzymatic activities of the mutant enzymes were 0.5%, 20.0%, and 38.5% of that of the wild type, respectively. Scatchard plot obtained for the wild type enzyme showed a biphasic profile, suggesting that the oligosaccharide binds to the chitosanase with two different binding sites (the high affinity site and the low affinity site). In contrast, Scatchard plot for E197A exhibited a monophasic profile, in which the slope of the line corresponds to that for the low affinity binding of the wild type enzyme. A monophasic profile was also obtained for D201A, but the slope of the line was similar to that of the high affinity binding. Thus, we conclude that Glu197 and Asp201 are responsible for oligosaccharide binding at the high affinity site and the low affinity site, respectively, which correspond to the (-n) subsites and the (+n) subsites (n=1, 2, and 3). The fluorescence quenching was very weak in D57A, suggesting a strong contribution of this residue to the oligosaccharide binding.