Dimension reduction of microbiome data linked Bifidobacterium and Prevotella to allergic rhinitis.

Dimension reduction has been used to visualise the distribution of multidimensional microbiome data, but the composite variables calculated by the dimension reduction methods have not been widely used to investigate the relationship of the human gut microbiome with lifestyle and disease. In the present study, we applied several dimension reduction methods, including principal component analysis, principal coordinate analysis (PCoA), non-metric multidimensional scaling (NMDS), and non-negative matrix factorization, to a microbiome dataset from 186 subjects with symptoms of  allergic rhinitis (AR) and 106 controls. All the dimension reduction methods supported that the distribution of microbial data points appeared to be continuous rather than discrete. Comparison of the composite variables calculated from the different dimension reduction methods showed that the characteristics of the composite variables differed depending on the distance matrices and the dimension reduction methods. The first composite variables calculated from PCoA and NMDS with the UniFrac distance were strongly associated with AR (FDR adjusted P = 2.4 × 10-4 for PCoA and P = 2.8 × 10-4 for NMDS), and also with the relative abundance of Bifidobacterium and Prevotella. The abundance of Bifidobacterium was also linked to intake of several nutrients, including carbohydrate, saturated fat, and alcohol via composite variables. Notably, the association between the composite variables and AR was much stronger than the association between the relative abundance of individual genera and AR. Our results highlight the usefulness of the dimension reduction methods for investigating the association of microbial composition with lifestyle and disease in clinical research.

Implications of Mitral Annular Calcification on Outcomes Following Mitral Transcatheter Edge-to-Edge Repair.

BACKGROUND: Limited data exist regarding the impact of mitral annular calcification (MAC) on outcomes of transcatheter edge-to-edge repair for mitral regurgitation (MR). METHODS: We retrospectively analyzed 968 individuals (median age, 79 [interquartile range, 70-86] years; 60.0% males; 51.8% with functional MR) who underwent an isolated, first-time intervention. Stratified by MAC extent per baseline transthoracic echocardiogram, the cohort was assessed for residual MR, functional status, all-cause mortality, heart failure hospitalizations, and mitral reinterventions post-procedure. RESULTS: Patients with above-mild MAC (n=101; 10.4%) were older and more likely to be female, exhibited a greater burden of comorbidities, and presented more often with severe, primary MR. Procedural aspects and technical success rate were unaffected by MAC magnitude, as was the significant improvement from baseline in MR severity and functional status along the first postprocedural year. However, the persistence of above-moderate MR or functional classes III and IV at 1 year and the cumulative incidence of reinterventions at 2 years were overall more pronounced within the above-mild MAC group (significant MR or functional impairment, 44.7% versus 29.9%, P=0.060; reinterventions, 11.9% versus 6.2%, P=0.033; log-rank P=0.035). No link was demonstrated between MAC degree and the cumulative incidence or risk of mortality and mortality or heart failure hospitalizations. Differences in outcomes frequencies were mostly confined to the primary MR subgroup, in which patients with above-mild MAC also experienced earlier, more frequent 2-year heart failure hospitalizations (20.8% versus 9.6%; P=0.016; log-rank P=0.020). CONCLUSIONS: Mitral transcatheter edge-to-edge repair in patients with and without above-mild MAC is equally feasible and safe; however, its postprocedural course is less favorable among those with primary MR.

Mitral Transcatheter Edge-to-Edge Repair in Nonagenarians.

BACKGROUND: There are scarce data regarding mitral transcatheter edge-to-edge repair (TEER) in individuals aged 90 years and above. We aimed to evaluate patient characteristics, procedural aspects, and outcomes in this rapidly growing group. METHODS: We retrospectively studied a single-centre database of 967 isolated, first-time interventions, 103 (10.7%) of which were performed in nonagenarians. Outcomes included all-cause mortality, heart failure (HF) hospitalizations, and the persistence of significant mitral regurgitation (MR) or New York Heart Association functional class III/IV during the first postprocedural year. Analyses were repeated on a 204-patient, propensity score-matched subcohort, controlling for MitraScore elements, sex, race, MR etiology, functional status, atrial fibrillation/flutter, and procedural urgency. RESULTS: Compared with subjects below 90 years of age, nonagenarians were more likely to be white women of higher socioeconomic status; had a higher interventional risk, driven mainly by age and chronic kidney disease; presented more often with primary MR (71.8 vs 39.1%, P < 0.001); and exhibited less advanced biochemical/echocardiographic indices of cardiac remodelling. Further, their procedures were more commonly nonurgent and used fewer devices. A similarly high (> 97%) technical success rate was achieved in the 2 study groups. Likewise, no intergroup differences were observed in the rates or cumulative incidences of any of the explored endpoints, and neither of the outcomes' risks was associated with age 90 and above. Comparable outcomes were also noted in the propensity score-matched subgroups. CONCLUSIONS: In our experience, mitral TEER was equally feasible, safe, and efficacious in patients below and above 90 years of age.

Preprocedural transthoracic echocardiography for predicting outcomes of transcatheter edge-to-edge repair for chronic primary mitral regurgitation.

INTRODUCTION AND OBJECTIVES: Limited data exist on the prognostic usefulness of transthoracic echocardiography preceding MitraClip for chronic primary mitral regurgitation (MR). We evaluated the predictive ability of transthoracic echocardiography in this setting. METHODS: A total of 410 patients (median age, 83 years, 60.7% males) were included in the study. The primary outcome was the 1-year composite of all-cause mortality or heart failure hospitalization. Secondary endpoints encompassed individual elements of the primary outcome, the persistence of significant functional impairment or above-moderate MR at 1 year, and above-mild MR at 1-month. RESULTS: The only parameter associated with the risk of the primary outcome was a ventricular end systolic diameter index of ≥2.1 cm/m2, corresponding to the cohort's 4th quartile (HR, 2.44; 95%CI, 1.09-4.68; P=.022). Concurrently, higher left atrial volume index (LAVi) and a mid-diastolic medial-lateral mitral annular diameter (MAD) equal to or above the cohort's median of 32.2mm were linked to a higher probability of death and heart failure hospitalization, respectively. LAVi of ≥ 60mL/m2, above-mild mitral annular calcification, and above-moderate tricuspid regurgitation conferred higher odds of functional class III-IV or above-moderate MR persistence. All variables except LAVi and MAD, as well as indexed mid-diastolic medial-lateral MAD of ≥ 20.2mm/m2 and mitral effective regurgitant orifice area of ≥ 0.40 cm2, were associated with greater-than-mild MR at 1 month. CONCLUSIONS: Preprocedural increased indexed left heart dimensions, mainly left ventricular end-systolic diameter index, MAD, mitral annular calcification, mitral effective regurgitant orifice area, and tricuspid regurgitation mark a less favorable course post-MitraClip for chronic primary MR.

Prognostic value of left ventricular global longitudinal strain in transcatheter edge-to-edge repair for chronic primary mitral regurgitation.

AIMS: Left ventricular global longitudinal strain (LVGLS) is a known outcome predictor in transcatheter edge-to-edge repair (TEER) for functional mitral regurgitation (MR). We aimed to assess its prognostic yield in the setting of TEER for chronic primary MR. METHODS AND RESULTS: We conducted a single-centre, retrospective analysis of 323 consecutive patients undergoing isolated, first-time procedures. Stratified by baseline LVGLS quartiles (≤-19%, -18.9% to -16%, -15.9% to -12%, >-12%), the cohort was evaluated for the primary composite outcome of all-cause mortality or heart failure hospitalizations, as well as secondary endpoints consisting of mitral reinterventions and the persistence of significant residual MR and/or functional disability-all along the first year after intervention. Subjects with worse (i.e. less negative) LVGLS exhibited higher comorbidity, more advanced HF, and elevated procedural risk. Post-TEER, those belonging to the worst LVGLS quartile group sustained increased mortality (16.9% vs. 6.3%, Log-Rank P = 0.005, HR 1.75, 95% CI 1.08-4.74, P = 0.041) and, when affected by LV dysfunction/dilatation, more primary outcome events (21.1% vs. 11.5%, Log-Rank P = 0.037, HR 1.68, 95% CI 1.02-5.46, P = 0.047). No association was demonstrated between baseline LVGLS and other endpoints. Upon exploratory analysis, 1-month post-procedural LVGLS directly correlated with and was worse than its baseline counterpart by 1.6%, and a more impaired 1-month value-but not the presence/extent of deterioration-conferred heightened risk for the primary outcome. CONCLUSION: TEER for chronic primary MR is feasible, safe, and efficacious irrespective of baseline LVGLS. Yet, worse baseline LVGLS forecasts a less favourable post-procedural course, presumably reflecting a higher-risk patient profile.