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ABSTRACT A 2-year longitudinal microbiome study of 22 patients who underwent colectomy with an ileal pouch anal anastomosis detected significant increases in distinct populations of Bacteroides during 9 of 11 patient visits that coincided with inflammation (pouchitis). Oligotyping and metagenomic short-read annotation identified Bacteroides populations that occurred in early samples, bloomed during inflammation, and reappeared after antibiotic treatment. Targeted cultivation of Bacteroides isolates from the same individual at multiple time points and from several patients detected subtle genomic changes, including the identification of rapidly evolving genomic elements that differentiate isogenic strains of Bacteroides fragilis from the mucosa versus lumen. Each patient harbored Bacteroides spp. that are closely related to commonly occurring clinical isolates, including Bacteroides ovatus , B. thetaiotaomicron , B. vulgatus , and B. fragilis , which contained unique loci in different patients for synthesis of capsular polysaccharides. The presence of unique Bacteroides capsular polysaccharide loci within different hosts and between the lumen and mucosa may represent adaptations to stimulate, suppress, and evade host-specific immune responses at different microsites of the ileal pouch. IMPORTANCE This longitudinal study provides an opportunity to describe shifts in the microbiomes of individual patients who suffer from ulcerative colitis (UC) prior to and following inflammation. Pouchitis serves as a model for UC with a predictable incidence of disease onset and enables prospective longitudinal investigations of UC etiology prior to inflammation. Because of insufficient criteria for predicting which patients will develop UC or pouchitis, the interpretation of cross-sectional study designs suffers from lack of information about the microbiome structure and host gene expression patterns that directly correlate with the onset of disease. Our unique longitudinal study design allows each patient to serve as their own control, providing information about the state of the microbiome and host prior to and during the course of disease. Of significance to the broader community, this study identifies microbial strains that may have genetic elements that trigger the onset of disease in susceptible hosts.

ObjectivesTo identify number of cases needed to maximize device success and minimize adverse events after transfemoral transcatheter aortic valve replacement (TF‐TAVR), and determine if adverse events were linked to the technical performance learning curve.BackgroundTF‐TAVR is a complex procedure with an incompletely characterized learning curve for clinical outcomes.MethodsFrom 4/2007–2/2012, 1521 patients underwent TF‐TAVR in the PARTNER‐I trial. Outcomes learning curves were defined as number of cases needed to reach a plateau for device success, adverse events, and post‐procedure length of stay. Institutional variation was accounted for by mixed‐model non‐linear techniques, which were also used to identify contribution of the procedure time learning curve to 30‐day major adverse events and length of stay.ResultsEighty percent device success was achieved after 22 cases; major vascular complications fell below 5% after 70 cases and major bleeding below 10% after 25 cases. It took an average of 28 cases to achieve a consistent low risk of 30‐day major adverse events, but institutions entering in the middle of the trial achieved it after about 26. The most significant correlate of 30‐day major adverse events and post‐procedure length of stay was procedure time (P < 0.0001). However, this association was related to patient and unmeasured variables, not the procedure time learning curve (P = 0.6).ConclusionsBy end of trial, a consistent low risk of adverse events was achieved after ∼26 cases. However, these improved results were due to change in patient risk profile; outcomes were not linked to the technical performance learning curve. © 2015 Wiley Periodicals, Inc.

ObjectivesTo assess technical performance learning curves of teams performing transfemoral transcatheter aortic valve replacement (TF‐TAVR).BackgroundTF‐TAVR is a new procedure for treating severe aortic stenosis. The number of cases required for procedural efficiency is unknown.MethodsIn the PARTNER‐I trial, 1,521 patients underwent TF‐TAVR from 4/2007–2/2012. Learning curve analysis of technical performance metrics was performed using institution‐specific patient sequence number, interval between procedures, and institutional trial entry date. Learning curve characteristics were assessed using semi‐parametric and parametric mixed‐effects models.ResultsAs patient sequence number increased, average procedure time decreased from 154 to 85 minutes (P < 0.0001), and fluoroscopy time from 28 to 20 minutes (P < 0.0001). Procedure time plateaued at an average of 83 minutes (range 52–140). Procedure time plateau was dynamic during the course of the trial, averaging 25 cases (range 21–52) by its end. The later institutions enrolled in the trial, the shorter the initial procedure time. During the trial, percutaneous rather than surgical access increased from 7.9% to 69%.ConclusionsTechnical performance learning curves exist for TF‐TAVR; procedural efficiency increased with experience, with concomitant decreases in radiation and contrast media exposure. The number of cases needed to achieve efficiency decreased progressively, with optimal procedural performance reached after approximately 25 cases for late‐entering institutions. Knowledge and experience accumulated by early TF‐TAVR institutions were disseminated, shortening the learning curve of late‐entering institutions. Technological advances resulting from learning during the trial moved the field from initial conservative surgical cut‐down to percutaneous access for most patients. © 2015 Wiley Periodicals, Inc.

Background— Tricuspid regurgitation (TR) and right ventricular (RV) dysfunction adversely affect outcomes in patients with heart failure or mitral valve disease, but their impact on outcomes in patients with aortic stenosis treated with transcatheter aortic valve replacement has not been well characterized. Methods and Results— Among 542 patients with symptomatic aortic stenosis treated in the Placement of Aortic Transcatheter Valves (PARTNER) II trial (inoperable cohort) with a Sapien or Sapien XT valve via a transfemoral approach, baseline TR severity, right atrial and RV size and RV function were evaluated by echocardiography according to established guidelines. One-year mortality was 16.9%, 17.2%, 32.6%, and 61.1% for patients with no/trace (n=167), mild (n=205), moderate (n=117), and severe (n=18) TR, respectively ( P <0.001). Increasing severity of RV dysfunction as well as right atrial and RV enlargement were also associated with increased mortality ( P <0.001). After multivariable adjustment, severe TR (hazard ratio, 3.20; 95% confidence interval, 1.50–6.82; P =0.003) and moderate TR (hazard ratio, 1.60; 95% confidence interval, 1.02–2.52; P =0.042) remained associated with increased mortality as did right atrial and RV enlargement, but not RV dysfunction. There was an interaction between TR and mitral regurgitation severity ( P =0.04); the increased hazard of death associated with moderate/severe TR only occurred in those with no/trace/mild mitral regurgitation. Conclusions— In inoperable patients treated with transcatheter aortic valve replacement, moderate or severe TR and right heart enlargement are independently associated with increased 1-year mortality; however, the association between moderate or severe TR and an increased hazard of death was only found in those with minimal mitral regurgitation at baseline. These findings may improve our assessment of anticipated benefit from transcatheter aortic valve replacement and support the need for future studies on TR and the right heart, including whether concomitant treatment of TR in operable but high-risk patients with aortic stenosis is warranted. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT01314313.

Background— The higher risk of adverse outcomes after transapical (TA) versus transfemoral (TF) transcatheter aortic valve replacement (TAVR) could be attributable to TA-TAVR being an open surgical procedure or to clinical differences between TA- and TF-TAVR patients. We compared outcomes after neutralizing patient differences using propensity score matching. Methods and Results— From April 2007 to February 2012, 1100 Placement of Aortic Transcatheter Valves (PARTNER)-I patients underwent TA-TAVR and 1521 underwent TF-TAVR with Edwards SAPIEN balloon-expandable bioprostheses. Propensity matching based on 111 preprocedural variables, exclusive of femoral access morphology, identified 501 well-matched patient pairs (46% of possible matches), 95% of whom had peripheral arterial disease. Matched TA-TAVR patients experienced more adverse procedural events, longer length of stay (5 versus 8 days; P <0.0001), and slower recovery (New York Heart Association class I, 31% versus 38% at 30 days, equalizing by 6 months at 51% versus 47%); stroke risk was similar (3.4% versus 3.3% at 30 days and 6.0% versus 6.7% at 3 years); mortality was elevated for the first 6 postprocedural months (19% versus 12%; P =0.01); but aortic regurgitation was less (34% versus 52% mild and 8.9% versus 12% moderate to severe at discharge, P =0.001; 36% versus 50% mild and 10% versus 15% moderate to severe at 6 months, P <0.0001). Conclusions— The likelihood of adverse periprocedural events and prolonged recovery is greater after TA-TAVR than TF-TAVR in vasculopathic patients after accounting for differences in cardiovascular risk factors, although stroke risk is equivalent and aortic regurgitation is less. As smaller delivery systems permit TF-TAVR in many of these patients, we recommend a TF-first access strategy for TAVR when anatomically feasible. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT00530894.

Objective Takayasu arteritis is a rare large vessel vasculitis with incompletely understood etiology. This study was undertaken to perform the first unbiased genome‐wide association analysis of Takayasu arteritis. Methods Two independent cohorts of patients with Takayasu arteritis from Turkey and North America were included in our study. The Turkish cohort consisted of 559 patients and 489 controls, and the North American cohort consisted of 134 patients and 1,047 controls of European ancestry. Genotyping was performed using the Omni1‐Quad and Omni2.5 genotyping arrays. Genotyping data were subjected to rigorous quality control measures and subsequently analyzed to discover genetic susceptibility loci for Takayasu arteritis. Results We identified genetic susceptibility loci for Takayasu arteritis with a genome‐wide level of significance in IL6 (rs2069837) (odds ratio [OR] 2.07, P = 6.70 × 10 −9 ), RPS9 / LILRB3 (rs11666543) (OR 1.65, P = 2.34 × 10 −8 ), and an intergenic locus on chromosome 21q22 (rs2836878) (OR 1.79, P = 3.62 × 10 −10 ). The genetic susceptibility locus in RPS9 / LILRB3 lies within the leukocyte receptor complex gene cluster on chromosome 19q13.4, and the disease risk variant in this locus correlates with reduced expression of multiple genes including the inhibitory leukocyte immunoglobulin‐like receptor gene LILRB3 ( P = 2.29 × 10 −8 ). In addition, we identified candidate susceptibility genes with suggestive levels of association ( P < 1 × 10 −5 ) with Takayasu arteritis, including PCSK5, LILRA3, PPM1G/NRBP1 , and PTK2B . Conclusion Our findings indicate novel genetic susceptibility loci for Takayasu arteritis and uncover potentially important aspects of the pathophysiology of this form of vasculitis.