Anoxygenic phototroph of the Chloroflexota uses a type I reaction centre

Scientific exploration of phototrophic bacteria over nearly 200 years has revealed large phylogenetic gaps between known phototrophic groups that limit understanding of how phototrophy evolved and diversified1,2. Here, through Boreal Shield lake water incubations, we cultivated an anoxygenic phototrophic bacterium from a previously unknown order within the Chloroflexota phylum that represents a highly novel transition form in the evolution of photosynthesis. Unlike all other known phototrophs, this bacterium uses a type I reaction centre (RCI) for light energy conversion yet belongs to the same bacterial phylum as organisms that use a type II reaction centre (RCII) for phototrophy. Using physiological, phylogenomic and environmental metatranscriptomic data, we demonstrate active RCI-utilizing metabolism by the strain alongside usage of chlorosomes3 and bacteriochlorophylls4 related to those of RCII-utilizing Chloroflexota members. Despite using different reaction centres, our phylogenomic data provide strong evidence that RCI-utilizing and RCII-utilizing Chloroflexia members inherited phototrophy from a most recent common phototrophic ancestor. The Chloroflexota phylum preserves an evolutionary record of the use of contrasting phototrophic modes among genetically related bacteria, giving new context for exploring the diversification of phototrophy on Earth.

First-Line Chemoimmunotherapy versus Sequential Platinum-Based Chemotherapy Followed by Immunotherapy in Patients with Non-Small Cell Lung Cancer with ≤49% Programmed Death-Ligand 1 Expression: A Real-World Multicenter Retrospective Study

BACKGROUND

The long overall survival (OS) observed among patients with non-small cell lung cancer (NSCLC) with high programmed death-ligand 1 (PD-L1) expression in chemoimmunotherapy (CIT) groups in previous phase III trials suggests the limited efficacy of CIT among the subgroup with ≤49% PD-L1 expression on tumor cells. Hence, sequential treatment with first-line platinum-based chemotherapy followed by second-line immune checkpoint inhibitor treatment (SEQ) is an option. This study examined whether first-line CIT would provide better outcomes than SEQ in patients with advanced NSCLC with ≤49% PD-L1 expression.

METHODS

This retrospective study evaluated patients with untreated NSCLC who received first-line CIT or SEQ at nine hospitals in Japan. OS, progression-free survival (PFS), PFS-2 (the time from first-line treatment to progression to second-line treatment or death), and other related outcomes were evaluated between the CIT and SEQ groups.

RESULTS

Among the 305 enrolled patients, 234 eligible patients were analyzed: 165 in the CIT group and 69 in the SEQ group. The COX proportional hazards model suggested a significant interaction between PD-L1 expression and OS (p = 0.006). OS in the CIT group was significantly longer than that in the SEQ group in the 1-49% PD-L1 expression subgroup but not in the <1% PD-L1 expression subgroup. Among the subgroup with 1-49% PD-L1 expression, the CIT group exhibited longer median PFS than the SEQ group (CIT: 9.3 months (95% CI: 6.7-14.8) vs. SEQ:5.5 months (95% CI: 4.5-6.1); p < 0.001), while the median PFS in the CIT group was not statistically longer than the median PFS-2 in the SEQ group (p = 0.586). There was no significant difference between the median PFS in the CIT and SEQ groups among the <1% PD-L1 expression subgroup (p = 0.883); the median PFS-2 in the SEQ group was significantly longer than the median PFS in the CIT group (10.5 months (95% CI: 5.9-15.3) vs. 6.4 months (95% CI: 4.9-7.5); p = 0.024).

CONCLUSIONS

CIT is recommended for patients with NSCLC with 1-49% PD-L1 expression because it significantly improved OS and PFS compared to SEQ. CIT had limited benefits in patients with <1% PD-L1 expression, and the median PFS-2 in the SEQ group was significantly longer than the median PFS in the CIT group. These findings will help physicians select the most suitable treatment option for patients with NSCLC, considering PD-L1 expressions.

Predictive Value of Modified Glasgow Prognostic Score and Persistent Inflammation among Patients with Non-Small Cell Lung Cancer Treated with Durvalumab Consolidation after Chemoradiotherapy: A Multicenter Retrospective Study

BACKGROUND

Durvalumab consolidation after chemoradiotherapy (CRT) is a standard treatment for locally advanced non-small cell lung cancer (NSCLC). However, studies on immunological and nutritional markers to predict progression-free survival (PFS) and overall survival (OS) are inadequate. Systemic inflammation causes cancer cachexia and negatively affects immunotherapy efficacy, which also reflects survival outcomes.

PATIENTS AND METHODS

We retrospectively investigated 126 patients from seven institutes in Japan.

RESULTS

The modified Glasgow Prognostic Score (mGPS) values, before and after CRT, were the essential predictors among the evaluated indices. A systemic inflammation-based prognostic risk classification was created by combining mGPS values before CRT, and C-reactive protein (CRP) levels after CRT, to distinguish tumor-derived inflammation from CRT-induced inflammation. Patients were classified into high-risk (n = 31) and low-risk (n = 95) groups, and the high-risk group had a significantly shorter median PFS of 7.2 months and an OS of 19.6 months compared with the low-risk group. The hazard ratios for PFS and OS were 2.47 (95% confidence interval [CI]: 1.46-4.19, p < 0.001) and 3.62 (95% CI: 1.79-7.33, p < 0.001), respectively. This association was also observed in the subgroup with programmed cell death ligand 1 expression of ≥50%, but not in the <50% subgroup. Furthermore, durvalumab discontinuation was observed more frequently in the high-risk group than in the low-risk group.

CONCLUSION

Combining pre-CRT mGPS values with post-CRT CRP levels in patients with locally advanced NSCLC helps to predict the PFS and OS of durvalumab consolidation after CRT.

Impact of respiratory bacterial infections on mortality in Japanese patients with COVID-19: a retrospective cohort study

BACKGROUND

Although cases of respiratory bacterial infections associated with coronavirus disease 2019 (COVID-19) have often been reported, their impact on the clinical course remains unclear. Herein, we evaluated and analyzed the complication rates of bacterial infections, causative organisms, patient backgrounds, and clinical outcome in Japanese patients with COVID-19.

METHODS

We performed a retrospective cohort study that included inpatients with COVID-19 from multiple centers participating in the Japan COVID-19 Taskforce (April 2020 to May 2021) and obtained demographic, epidemiological, and microbiological results and the clinical course and analyzed the cases of COVID-19 complicated by respiratory bacterial infections.

RESULTS

Of the 1,863 patients with COVID-19 included in the analysis, 140 (7.5%) had respiratory bacterial infections. Community-acquired co-infection at COVID-19 diagnosis was uncommon (55/1,863, 3.0%) and was mainly caused by Staphylococcus aureus, Klebsiella pneumoniae and Streptococcus pneumoniae. Hospital-acquired bacterial secondary infections, mostly caused by Staphylococcus aureus, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia, were diagnosed in 86 patients (4.6%). Severity-associated comorbidities were frequently observed in hospital-acquired secondary infection cases, including hypertension, diabetes, and chronic kidney disease. The study results suggest that the neutrophil-lymphocyte ratio (> 5.28) may be useful in diagnosing complications of respiratory bacterial infections. COVID-19 patients with community-acquired or hospital-acquired secondary infections had significantly increased mortality.

CONCLUSIONS

Respiratory bacterial co-infections and secondary infections are uncommon in patients with COVID-19 but may worsen outcomes. Assessment of bacterial complications is important in hospitalized patients with COVID-19, and the study findings are meaningful for the appropriate use of antimicrobial agents and management strategies.

The left ventricular remodeling assessment by cardiac magnetic resonance in chronic aortic regurgitation; implications for outcome

Background

Chronic aortic regurgitation (AR) causes left ventricular (LV) volume overload resulting in progressive LV remodeling, which negatively affect clinical outcome. Clinical Guidelines recommend assessment of LV remodeling by echocardiography, but little is known about comparative remodeling quantification by cardiac magnetic resonance (CMR) and association with outcomes.

Purpose

To assess LV remodeling in AR by CMR, compared with echocardiographic measures and determine its impact on clinical outcome.

Methods

Patients with native, ≥moderate, chronic AR by echocardiography who underwent CMR exam within 90 days of diagnosis from January 2012 to February 2020 were enrolled. The endpoint was a composite of death, heart failure hospitalization, and heart failure symptom exacerbation during follow-up.

Results

The 178 patients included had median age (IQR) of 58 years (44–69), and most (88%, n=158) presented with no or minimal symptoms (NYHA class I/II). At diagnosis symptomatic vs. no/minimal symptoms patients presented with much more advanced LV remodeling by CMR (EDVI 133 [83–151] vs. 96 [80–123] p=0.024, ESVI 66 [46–85] vs. 42 [30–58], P=0.001) while echocardiography showed limited differences (EDVI 76 [57–93] vs. 65 [54–87] p=0.507, ESVI 38 [30–58] vs. 27 [20–42], p=0.072). During follow-up (3.3 years [1.6–5.8]), aortic valve replacement (AVR) was performed in 49 patients. In patients with no/minimal symptoms, the composite endpoint occurred in 54 (34%) patients including eight deaths and 30 heart failure hospitalizations. Patients with LV end-systolic volume index (LVESVi) &gt;45 ml/m2 by CMR had higher likelihood for composite endpoint (Panel A) confirmed in multivariate models, adjusting for age, sex, AVR (time-dependent), EuroSCORE2, and LV End-systolic-dimension-index (LVESDi) &gt;25 mm/2, with adjusted hazard ratio 1.84 [1.02–3.33], p&lt;0.044 (Panel B). LVESVi by CMR was at least as powerful in determining clinical outcomes as guideline-recommended Doppler-Echocardiographic variables.

Conclusion

Assessment of LV remodeling by CMR in patients with clinically significant AR is feasible in routine clinical practice, detects with high sensitivity LV remodeling associated with development of HF symptoms and is independently predictive of clinical outcome. Hence, CMR provides a powerful tool for evaluation and risk stratification of patients with AR.

Funding Acknowledgement

Type of funding sources: None. Panel APanel B

Impact of left ventricular fibrosis and longitudinal systolic strain on outcomes in low gradient aortic stenosis

Background

The clinical utility of comprehensive cardiac magnetic resonance (CMR) for the assessment of myocardial structure and function remains unknown in patients with low gradient (LG) aortic stenosis (AS).

Purpose

This study sought to compare CMR characteristics of myocardial structure and function according to different flow / gradient patterns of AS: classical low flow LG (LFLG); paradoxical LFLG; normal flow LG; and high gradient, and to evaluate their impact on the outcomes of these patients.

Methods

International multicentric prospective study included 147 patients with LG moderate to severe AS and 18 patients with high gradient severe AS who underwent comprehensive CMR evaluation of left ventricular global longitudinal strain (LVGLS), extracellular volume fraction (ECV), and late gadolinium enhancement (LGE).

Results

Patients with classical LFLG (n=90) had more LV adverse remodeling and impaired longitudinal function including higher ECV, and higher LGE and volume, and worst LVGLS, compared to other patterns of AS. Over a median follow-up of 2-years, 43 deaths and 48 composite outcomes of death or heart failure hospitalization occurred in LG AS patients. As LVGLS or ECV worsened, risks of adverse events also increased (per tertile of LVGLS: HR [95% CI] for mortality, 1.50 [1.02–2.20]; p=0.04; HR [95% CI] for composite outcome, 1.45 [1.01–2.09]; p&lt;0.05) (per tertile of ECV: HR [95% CI] for mortality, 1.63 [1.07–2.49]; p=0.02; HR [95% CI] for composite outcome, 1.54 [1.02–2.33]; p=0.04). LGE presence was also associated with higher mortality (HR [95% CI], 2.27 [1.01–5.11]; p&lt;0.05) and risk of the composite outcome (HR [95% CI], 3.00 [1.16–7.73]; p=0.02). The risk of all-cause death and of the composite outcome increased in proportion to the number of impaired components (i.e. LVGLS, ECV and LGE) (Figure) with and without adjustment for age, true severe AS, classical LFLG, and aortic valve replacement as a time-varying covariate.

Conclusions

In this international multicentric study of LG AS, comprehensive CMR assessment of myocardial structure and function provides independent prognostic value that is cumulative and incremental to clinical and echocardiographic characteristics.

Funding Acknowledgement

Type of funding sources: None.

Computed tomography derived left ventricular global longitudinal strain associate with clinical outcomes in patients undergoing transcatheter aortic valve replacement

Funding Acknowledgements

Type of funding sources: None.

Background

Computed tomography angiography (CTA) is key imaging modality for procedure planning for transcatheter aortic valve replacement (TAVR). Functional assessment by CTA with LV global longitudinal strain (LVGLS) has recently shown to be feasible. However, there is limited data on its prognostic value in patients with severe aortic stenosis (AS) who treated with TAVR.

Purpose

To evaluate the association of baseline CTA-LVGLS with post-TAVR outcome.

Methods

 Patients who underwent contrast multiphasic gated CTA for TAVR planning were studied. LVGLS was measured using dedicated feature-tracking software (Medis®). Cox regression analysis evaluated the association of baseline LVGLS with a composite outcome of all-cause death and heart failure hospitalization after TAVR.

Results

A total of 431 patients were included (median [IQR] age, 83 [77,87]years; 44% female); the society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) score, 3.3 [2.3,5.1]%; CTA-LVGLS, -18.0 [-21.6,-14.2]%; LV ejection fraction was preserved at 60 [55,65]%. After a median follow-up of 19 [13,27] months, 99 composite outcomes occurred after TAVR. On multivariable Cox regression analysis, LVGLS was associated with the risk of composite outcome even after adjustment for baseline characteristics (Figure A). Patients with reduced LVGLS (above the median &gt;-18.0%) had higher risk of the composite outcome than those with preserved GLS (p = 0.003; Figure B).

Conclusion

Baseline CTA-LVGLS was associated with the risk of death or heart failure hospitalization over the clinical and echocardiographic characteristics in severe AS patients undergoing TAVR.

Abstract Figure.

Computed tomography characteristics of patients with functional MR receiving MitraClip

Funding Acknowledgements

Type of funding sources: None.

Background

Percutaneous leaflet repair with the MitraClip device (Abbott Vascular, Menlo Park, CA) is safe and effective in patients with severe functional mitral regurgitation (FMR). Residual or recurrent MR may occur in up to 40% of patients and is associated with persistent symptoms and impaired survival. The anatomical characteristics associated with residual or recurrent MR after MitraClip are not well defined by computed tomography angiography (CTA) in FMR population.

Methods

A retrospective analysis of patients with significant FMR, who underwent retrospective-gated CTA at Minneapolis Heart Institute between July 2015 to January 2020, identified those who underwent percutaneous leaflet repair with MitraClip. Anatomical and functional parameters were assessed by pre-procedure CTA and compared between those with and without residual (≥2) MR.

Results

  A total of 25 patients were included (median[Q1, Q3]; age, 80[75, 85]; 44% men) and classified into ventricular FMR (V-FMR, n = 12) and atrial FMR (A-FMR, n = 13) according to anatomical and functional characteristics by CTA. 50% of V-FMR and 38% of A-FMR had residual/worsening MR. Among V-FMR patients with residual/worsening MR, shorter coaptation length was observed (2.2[2, 2.3] mm vs. 3.5[3, 4], p = 0.006) (Figure). No differences in anatomical or functional characteristics were seen in A-FMR patients.

Conclusion

Longer coaptation length in V-FMR is predictive of successful MitraClip procedure, whereas mitral annulus size and cardiac volumes are not.

&lt;Ventricular FMR&gt; Total (N = 12) No residual/no worsening MR (N = 6) Residual/worsening MR (N = 6) P value Septal-lateral diameter, mm 31.9 (30.5, 37.9) 32.2 (30.1, 39.8) 31.9 (29.5, 35) 0.749 Annulus area, cm&sup2; 11.2 (10.4, 13.6) 11.3 (10.1, 14.6) 11.1 (9.6, 12.6) 0.631 Tenting area, cm&sup2; 1.6 (1.3, 2.1) 1.6 (1.2, 2.2) 1.7 (1.2, 2.3) 0.873 Tenting height, mm 8.5 (6.5, 9.7) 8.5 (6.6, 9.3) 8.3 (6.3, 10.1) 0.749 Coaptation length, mm 2.6 (2.1, 3.5) 3.5 (3.0, 4.0) 2.2 (2.0, 2.3) 0.006 &lt;Atrial FMR&gt; Total (N = 13) No residual/no worsening MR (N = 8) Residual/worsening MR (N = 5) P value Septal-lateral diameter, mm 32.3 (29.5, 39.0) 32.0 (29.2, 39.9) 34.3 (30.8, 39.02) 0.464 Annulus area, cm&sup2; 10.3 (9.2, 14.7) 10.2 (9.0, 14.6) 12.4 (9.4, 14.7) 0.661 Tenting area, cm&sup2; 1.2 (0.8, 1.8) 1.1 (0.7, 2.2) 1.3 (0.7, 1.8) 0.884 Tenting height, mm 5.5 (4.1, 6.9) 6.3 (4.1, 8.7) 4.6 (3.7, 5.8) 0.213 Coaptation length, mm 2.3 (1.5, 2.8) 2.5 (1.4, 3.5) 1.9 (1.5, 2.6) 0.464 Comparison of baseline CT parameters between no residual/ no worsening MR and residual/ worsening MR Abstract Figure.

Functional DSCT assessment of tricuspid regurgitation: AROA reproducibility and comparison with 3D TEE

Funding Acknowledgements

Type of funding sources: None.

onbehalf

Minneapolis Heart Institute Foundation

Background

Tricuspid regurgitation (TR) assessment by echocardiography is often challenging. Functional dual-source CT (DSCT) with third-generation scanners allows accurate evaluation of leaflet anatomy and mobility.

Purpose

Investigate the reproducibility of tricuspid anatomical regurgitant orifice area (AROA) by DSCT, and its correlation with TR quantification by 3D TEE.

Methods

We evaluated patients with symptomatic TR referred for transcatheter tricuspid repair. DSCT (SOMATOM Force [Siemens, Erlangen, Germany]) and 3D TEE was performed on the same day as part of our institutional registry. DSCT scans were retrospective and ECG-gated, with a contrast protocol to enhance the right heart. The reproducibility of tricuspid AROA was assessed in 20 patients. The tricuspid AROA was compared with the TR severity (5-grade classification) and the 3D VCA by TEE (Panel 1).

Results

We included 60 patients (Table). The AROA had excellent intra and interobserver reliability (ICC 0.99 [0.97, 0.99] and 0.99 [0.96, 0.99]). We found a stepwise increase in tricuspid AROA from moderate to torrential TR (Panel 2A). Of 60 patients, 3D VCA was feasible in 39; in those, we found an excellent linear correlation of AROA and 3D VCA (Panel 2B).

Conclusions

Tricuspid AROA by DSCT was reproducible, showed a stepwise increase from moderate to massive TR and correlated with 3D VCA by TEE.

Baseline Patient Characteristics All (n = 60) Age, years 82 ± 7 BSA, m2 1.8 ± 0.2 NYHA III-IV, n(%) 42 (70) Atrial Fibrilation 55 (91) Hypertension 44 (73) Pulmonary Hypertension 34 (56) Chronic Kidney Disease 25 (44) Coronary Artery Disease 17 (28) Chronic Lung Disease 14 (23) Permanent Pacemaker 13 (21) Diabetes Mellitus 10 (17) Mitral Valve Repair (MitraClip) 9 (15) Mitral Valve Replacement 7 (12) Mitral Valve Repair 3 (5) Aortic Valve Replacement 5 (8) Values are mean ± SD and n (%). BSA = body surface area. Abstract Figure. Panels

Left ventricular remodeling after transcatheter mitral valve replacement with Tendyne

Background

Data on changes in left atrial (LA) and left ventricular (LV) volumes after transcatheter mitral valve replacement (TMVR) are limited.

Purpose

This study sought to describe the anatomical and functional changes in left-sided cardiac chambers by computed tomography angiography (CTA) from baseline to 1-month after TMVR with Tendyne prosthesis.

Methods

We analyzed patients who underwent TMVR with Tendyne prosthesis (Abbott Structural, Menlo Park, CA) between 2015 and 2018. Changes in LV end-diastolic volume (LVEDV), ejection fraction (LVEF), mass (LV mass), LA volume and global longitudinal strain (GLS) were assessed at baseline and at 1-month after TMVR with CTA. Specific Tendyne implant characteristics were identified and correlated with remodeling changes.

Results

A total of 36 patients (mean age 73±8 years, 78% men, 86% secondary MR) were studied. There were significant decreases in LVEDV (268±68 vs. 240±66ml, p&lt;0.001), LVEF (38±10 vs. 32±11%, p&lt;0.001), LV mass (126±37 vs. 117±32g, p&lt;0.001), LA volume (181±74 vs. 174±70 ml, p=0.027) and GLS (−12.6±5.1 vs. −9.5±4.0%, p&lt;0.001) from baseline to 1-month follow-up. Favorable LVEDV reverse-remodeling occurred in the majority (30 of 36 patients, or 83%). Closer proximity of the Tendyne apical pad to the true apex was predictive of favorable remodeling (pad distance: 25.0±7.7 vs. 33.5±8.8mm, p=0.02 for those with and without favorable remodeling).

Conclusions

TMVR with Tendyne results in favorable left-sided chamber remodeling in the majority of patients treated, as detected on CTA at 1-month after implantation. CTA identifies the favorable post-TMVR changes, which could be related to specific characteristics of the device implantation.

Funding Acknowledgement

Type of funding source: None

P212 Computed tomography derived left ventricular outflow tract area downgrades severity of prosthesis-patient mismatch after transcatheter aortic valve replacement

Background

Prosthesis-patient mismatch (PPM) is associated with poor outcomes after surgical aortic valve replacement, but evidence in the era of transcatheter aortic valve replacement (TAVR) is small. Although PPM is conventionally defined by transthoracic echocardiogram (TTE) derived indexed effective orifice area (EOAi), TTE may underestimate left ventricular outflow tract (LVOT) area when compared with cardiac computed tomography angiography (CTA).

Purpose

To evaluate the inter-modality (TTE vs CTA) agreement and inter-valve (balloon-expanding valve (BEV) vs. self-expandable valve (SEV)) differences in EOAi and the severity of PPM after TAVR.

Methods

We analyzed all patients who underwent TAVR between 2015 to 2017and who had both of CTA and TTE at 30-days after TAVR. EOAi was calculated using the continuity equation and then indexed to body surface area as per guidelines using TTE derived LVOT diameter (EOAi-TTE) or post-procedure CTA derived LVOT area (EOAi-CTA). The external LVOT diameter was measured at inflow of TAVR bioprosthetic stent frame as per recommendations. The EOAi was used to define the grading severity of PPM: None (&gt; 0.85 cm²/m²); Moderate (0.65 to 0.85 cm²/m²); and Severe (&lt; 0.65 cm²/m²). Paired or Student t-test and Chi-square test were used to assess the inter-modality and inter-valve difference.

Results

A total of 280 patients were included (the mean age, 81.2 ± 8.1 years; 48%, female). BEV was used in 150 patients (54%). The mean EOAi-TTE vs. EOAi-CTA was 1.00 ± 0.32 and 1.41 ± 0.50 cm²/m², respectively, p &lt; 0.001. Prevalence of severe (TTE 9% versus CTA 4%, p &lt; 0.01) and moderate (TTE 28% versus CTA 7%, p &lt; 0.01) PPM was lower when adjudicated by CTA (Figure-Panel A). There was a trends towards smaller EOAi by either TTE (0.97 ± 0.31 vs. 1.04 ± 0.33, p = 0.07) or CTA (1.38 ± 0.45 vs. 1.46 ± 0.56, p = 0.21) for BEV vs. SEV (Figure-Panel B). There was no significant difference in the severity of PPM defined by either EOAi-TTE (Figure-Panel C) or EOAi-CTA (Figure-Panel D) between these patients.

Conclusion

EOAi-CTA was larger and downgraded the severity of PPM than the EOAi-TTE. There was no significant difference in the severity of PPM defined by post-procedure CT between patients treated with BEV and those with SEV.

Abstract P212 Figure.

P5568Disease stages of structural and functional cardiac changes associate with outcomes in patients with mitral regurgitation receiving mitral valve intervention

Background/Introduction

Severe mitral regurgitation (MR) produces volume overload resulting in progressive cardiac dysfunction that can extend beyond the left-sided chambers. It is unknown whether a specific MR staging system, that would quantify the extent of structural and functional cardiac changes, would be associated with outcomes in severe MR patients receiving mitral valve (MV) intervention.

Purpose

To examine the clinical utility of a novel MR staging system, based on the extent of cardiac damage, for prediction of clinical outcomes for patients with severe MR who underwent surgical or transcatheter therapy.

Methods

Patients were categorized into five stages using pre-procedural echocardiography; Stage 0: no other cardiac damage detected; Stage 1: Left atrium (LA) abnormality, as defined by the presence of atrial fibrillation or LA chamber enlargement; Stage 2: LV dysfunction, as defined by LV ejection fraction <60%; Stage 3: Pulmonary artery vasculature or tricuspid valve abnormality, as defined by the presence of systolic pulmonary arterial pressure ≥60 mmHg) or ≥grade 2 tricuspid regurgitation; and Stage 4: Right ventricular (RV) disease as defined by the presence of >mild RV dysfunction. The primary outcomes were all-cause mortality, and the combined endpoint of death or heart failure rehospitalization at one-year follow-up.

Results

A total of 696 patients with MR (age 70±14 years; 60% men) who underwent MV surgery (69%) or transcatheter MV repair with MitraClip device (31%) were examined. Prevalences of stage 0, 1, 2, 3, and 4 were 6.6%, 34.6%, 20.0%, 26.6%, and 12.2%, respectively. The median follow-up time was 15 months (IQR, 6.4, 24.4 months). At one-year, there was graded increase in all-cause death and in the combined endpoint of death or heart failure rehospitalization with each MR stage (Figure). In multivariate models, these associations remained independently associated with both one-year endpoints for patients receiving either surgical or transcatheter interventions.

Figure 1

Conclusion

This novel MR staging system is practical and may improve clinical risk stratification of patients with severe MR being considered for MV interventions.

P302Prediction of long-term success with global longitudinal strain in patients treated with transcatheter mitral repair

Background

Transcatheter mitral valve repair with MitraClip is effective for patients with mitral regurgitation (MR) and high or prohibitive surgical risk. Global longitudinal strain (GLS) allows evaluation of subclinical myocardial dysfunction, but its incremental clinical utility is unknown in patients treated with MitraClip.

Purpose

To evaluate the relation of baseline GLS and 1-year combined endpoint of all-cause death and heart failure hospitalization in patients treated with MitraClip.

Methods

We analyzed all patients who underwent MitraClip in our hospital between 2012 and 2018. Baseline LV GLS was obtained by 2D speckle tracking echocardiography, averaging the 18-segments from 3 apical views. Receiver operating characteristic (ROC) analyses were used to assess GLS cut-point associated with mortality. Multivariate models with Cox regression tested its relationship after adjustment of baseline characteristics.

Results

We examined 155 patients (mean age 83±7 years, 52% men; mean LVEF 56±10%, the Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) for repair 6.62±5.22%). At one-year, there were 30 deaths and 9 of heart failure hospitalizations, totalizing a composite outcome rate of 25.2%. Baseline GLS (per 1% increase) was associated with 1-year combined endpoint before (HR 1.10, 95% CI 1.02–1.19, p=0.02) and after (HR 1.10, 95% CI 1.01–1.20, p=0.04, respectively) adjustment for baseline characteristics. The optimal value of GLS for discriminating mortality at 1-year was −14.5% (AUC, 0.60; sensitivity 40%, specificity 76%). After accounting for baseline characteristics, patients with reduced GLS (>−14.5%) had worse 1-year combined endpoint than those with preserved GLS (≤−14.5%) (p<0.001; Figure).

Conclusions

Baseline GLS is independently associated with 1-year combined endpoint of all-cause mortality and/or heart failure hospitalization in patients who received transcatheter mitral valve repair. Detection of subclinical myocardial dysfunction by GLS may improve risk stratification and long-term success in these patients.

Acknowledgement/Funding

Valve Science Center, Minneapolis Heart Institute Foundation

1337Myocardial extracellular volume in patients with aortic stenosis undergoing valve intervention - A multicentre T1 mapping study

Background

The development of myocardial fibrosis is a key mechanism in the transition from compensated hypertrophy to heart failure in aortic stenosis (AS). Focal and diffuse fibrosis can be quantified using cardiac magnetic resonance (CMR) imaging late gadolinium-enhanced (LGE) and T1 mapping techniques.

Purpose

To assess T1 mapping measures of fibrosis in patients with severe AS referred for aortic valve intervention, and determine their associations with clinical characteristics, disease severity and long-term clinical outcome.

Methods

In this international prospective cohort study, patients with severe AS underwent contrast enhanced CMR with T1 mapping and LGE prior to aortic valve intervention. Image analysis was performed by a single core laboratory and the extracellular volume fraction [ECV%] calculated from T1 mapping images. The presence of LGE was determined visually and quantified using the full-width-at-half-maximum technique.

Results

Four-hundred and forty patients (70±10 years, 59% male) from ten international centres were enrolled. Aortic valve intervention was performed 15 [4 to 58] days following CMR. Within a follow-up of 3.8 [2.8 to 4.6] years, 52 patients died.

ECV% (mean 27.7±3.6%) correlated with increasing age, Society of Thoracic Surgeons Predicted Risk of Mortality score, known coronary artery disease, lower peak aortic-jet velocity, larger left ventricular (LV) mass, lower LV ejection fraction, and presence of LGE (P<0.05 for all). Following adjustment for all demographic and clinical variables, ECV% remained associated with age (P=0.028), LV ejection fraction (P<0.001) and presence of LGE (P=0.035).

Univariable predictors of all-cause mortality included age, male sex, impaired LV ejection fraction and presence of LGE (all P<0.05). A progressive increase in all-cause mortality was seen across tertiles of ECV% (17.3, 31.6 and 52.7 deaths per 1000 patient-years; log-rank test, P=0.009). ECV% was independently associated with all-cause mortality following adjustment for age, sex, impaired LV ejection fraction and presence of LGE (HR per unit increase in ECV: 1.10, 95%, (1.02–1.19), P=0.013).

ECV440 abstract iamge

Conclusion

In patients with severe aortic stenosis scheduled for aortic valve intervention, extracellular volume-based T1 mapping correlates with LV decompensation. ECV% is a strong independent predictor of late all-cause mortality and is a potential therapeutic target.

Impact of different timing of consuming sweet snack on postprandial glucose excursions in healthy women

AIMS

Our aim was to evaluate the acute effect of eating sweet snacks at different times of day on glycaemic parameters in young women without diabetes.

METHODS

In this randomized controlled three-treatment crossover study, 17 women [(means ± SD) age: 21.2 ± 0.8 years, BMI: 20.7 ± 2.5 kg/m2, HbA_1c: 36 ± 2 mmol/mol (5.1 ± 0.2%)] wore flash (continuous) glucose monitoring systems for 7 days. Each participant consumed identical test meals on days 4, 5 and 6, but consumed sweet snacks (baked cake: 498 kcal; 53.6 g of carbohydrate, 8.0 g of protein, 28.0 g of fat) at 12:30 (post-lunch), 15:30 (mid-afternoon) and 19:30 (post-dinner), respectively, on each of those days. Daily glycaemic parameters on those 3 days of snacking at different times of day were compared within-participant.

RESULTS

The mean amplitude of glycaemic excursions (3.54 ± 0.32 vs. 2.73 ± 0.20 mmol/L; P < 0.05), standard deviation of glucose (1.20 ± 0.11 vs. 0.92 ± 0.07 mmol/L; P < 0.05), incremental area under the curve (IAUC) for glucose at 12:00-07:00 (986 ± 89 vs. 716 ± 88 mmol/L × min; P < 0.05) and IAUC at 07:00-10:00 the next day (141 ± 17 vs. 104 ± 12 mmol/L × min; P < 0.05) when the snack was eaten post-dinner were all significantly higher than with mid-afternoon snacking.

CONCLUSION

Eating sweet snacks post-dinner should be avoided because it worsens glucose excursions as well as postprandial glucose levels after both dinner and the following day's breakfast in young healthy (non-diabetic) women.

Impact of respiratory function on the progression from metabolically healthy non-overweight to metabolically abnormal phenotype

BACKGROUND AND AIMS

Recent studies identified that metabolically abnormal non-overweight phenotype is a risk factor for cardiovascular diseases. However, only little is known about risk factors for the progression from metabolically healthy non-overweight (MHNO) to metabolically abnormal phenotype. In this study, we investigated the impact of respiratory function on the progression from MHNO to metabolically abnormal phenotype.

METHODS AND RESULTS

In this retrospective cohort study, 8949 (3872 men and 5077 women) individuals with MHNO, who participated in a health-checkup program from 2004 to 2015, were enrolled. Four metabolic factors (high-normal blood pressure or hypertension, impaired fasting glucose or diabetes, hypertriglyceridemia, and low HDL cholesterol concentration) were used to define metabolically healthy (less than two factors) or metabolically abnormal (two or more factors) phenotypes. Respiratory function was measured by spirometry. Over a median 4.0 years of follow-up, 927 participants progressed to metabolically abnormal phenotype. The percentage of FVC for predicted values (HR 0.98, 95% CI 0.93-1.03, p = 0.418) was not associated with the progression to metabolically abnormal phenotype after adjusting for covariates, including age, sex, alcohol consumption, exercise, smoking status, and body mass index, whereas the percentage of FEV₁ for predicted values (%FEV₁) (HR 0.87, 95% CI 0.84-0.91, p < 0.001) and the FEV₁/FVC ratio (HR 0.86, 95% CI 0.78-0.95, p = 0.004) were associated with the progression to metabolically abnormal phenotype.

CONCLUSION

Decrease in respiratory function in terms of %FEV₁ and the FEV₁/FVC ratio is associated with the progression to metabolically abnormal phenotype in individuals with MHNO.

Consuming snacks mid-afternoon compared with just after lunch improves mean amplitude of glycaemic excursions in patients with type 2 diabetes: A randomized crossover clinical trial

AIMS

Our aim was to explore the acute effects of consuming snacks at different times on glucose excursions in patients with type 2 diabetes (T2D).

METHODS

Seventeen patients with T2D [means±SD: age 67.4±9.4-years; BMI 23.5±3.1kg/m²; HbA_1c 55±6mmol/mol (7.2±1.0%)] were randomly assigned in this crossover study. Each participant wore a continuous glucose monitoring device for 4 days and consumed identical test meals on the second and third days, comprising breakfast at 0700h, lunch at 1200h and dinner at 1900h. Half the participants consumed 75kcal biscuits at 1230h (just after lunch) on the second day and at 1530h (mid-afternoon) on the third day, while the other half consumed snacks at the same times, but vice versa. Each patient's glucose parameters were compared against baseline for the 2days of snacking at different times of day.

RESULTS

Consuming snacks in the mid-afternoon led to significantly lower mean amplitudes of glycaemic excursions (mean±SEM: 5.19±0.48 vs. 6.90±0.69mmol/L, P<0.01; standard deviation: 1.75±0.17 vs. 2.16±0.21mmol/L, P<0.01) and incremental areas under the curve for glucose after dinner (479±76 vs. 663±104mmol/L per min, P<0.01) compared with snacking just after lunch, whereas mean glucose levels did not differ over the 2days.

CONCLUSION

These results suggest that consuming snacks well separated from lunch may be an effective way to suppress postprandial glucose levels and glycaemic excursions.

Magnetic Resonance Imaging Compared with Computed Tomography and Angiography in Moyamoya Disease

Magnetic resonance (MR) imaging performed in 13 patients with moyamoya disease was reviewed and compared with computed tomography (CT) and angiography. The MR findings consisted of occlusion of arteries, collateral vessels and parenchymal changes. Narrowing or occlusion of the middle cerebral artery and the supraclinoid portion of the internal carotid artery were seen in all hemispheres but one. Collateral vessels, cerebral infarcts and atrophy with dilatation of the ventricles were observed on MR imaging. In general, the MR findings correlated well with angiography regarding occlusive changes and moyamoya vessels but was less sensitive in a few cases. Because of its higher sensitivity in detecting occlusive changes and collateral vessels, MR imaging was superior to CT in the diagnosis of this disease.

Leukotriene C4contents, synthase and catabolic activity in human meningiomas

Leukotriene has been proposed as a factor of tumour induced brain oedema. Independently of its size, meningioma occasionally shows various extents of peritumoural oedema. We investigated LTC4 tissue contents, LTC4 catabolic and synthetic activity in 12 human meningiomas and their correlation with peritumoural oedema was studied. LTC4 contents were varied from 0.01 to 8.21 pg/mg tissue. When LTA4, an unstable expoxide intermediate was incubated with tumour homogenate, LTC4 was rapidly synthesized. However, LTC4 levels generated by incubating LTA4 with each homogenate were much different in each case. Degradation of LTC4 to LTD4, LTE4, and other polar materials was also rapid by incubation with tumour homogenates. Approximately 70% of added LTC4 was transformed to LTD4, LTE4 nor 6-trans LTB4 diastereoisomers during 30 min incubation at 37 degrees C. The results suggested that there were significant LTC4 tissue contents and LTC4 synthetic and catabolic activity in meningiomas. Oedema index ranged from 1.0 (no peritumoural oedema) to 67.5. No significant correlation, however, was observed not only between the LTC4 tissue contents and LTC4 synthetic or catabolic activities but also between each of these three parameters and peritumoural oedema. Thus, these results do not support a significant correlation of sulfidopeptide LTs with oedema formation in meningioma patients. Since leukotrienes are extremely unstable compounds, LTC4 tissue contents should be carefully discussed along with a consideration of rapid LTC4 synthesis and catabolism. Further role of leukotrienes in meningioma tissue should be studied.

Impact of low-carbohydrate diet on body composition: meta-analysis of randomized controlled studies

The effect of low-carbohydrate diet (LCD) on body composition, especially fat mass, in obese individuals remains to be elucidated. We performed a meta-analysis to provide quantitative summary estimates of the mean change of body weight (kg) and fat mass (kg) in LCD comparing to those in control diet. Literature searches were performed using EMBASE, MEDLINE and Cochrane Library until Dec 2014. Fourteen randomized controlled studies were included in this meta-analysis. Eight studies including very LCD (50 g carbohydrate or 10% calorie from carbohydrate) and seven studies including mild LCD (about 40% calorie from carbohydrate). Meta-analysis carried out on data of 1416 obese individuals, showed that LCD was associated with decrease in body weight (-0.70 kg [95% CI -1.07/-0.33]) or fat mass (-0.77 kg [-1.55/-0.32]). Subgroup meta-analysis of studies in over 12 months suggested that LCD was not associated with decrease in body weight (-0.44 kg [-0.94/0.07]), but LCD was associated with decrease in fat mass (-0.57 kg [-1.05/-0.09]). In addition, very LCD was associated with decrease in fat mass (-0.97 kg [-1.50/-0.44]), but mild LCD was not associated with decrease in fat mass (-0.43 kg [-1.15/0.33]). LCD, especially very LCD, might be effective for decrease in fat mass in obese individuals. © 2016 World Obesity.

Heart rate-corrected QT interval is a novel risk marker for the progression of albuminuria in people with Type 2 diabetes

AIMS

A close association between heart rate-corrected QT interval (QTc) and albuminuria in people with Type 2 diabetes has been reported in cross sectional studies. The aim of this study was to evaluate the relationship between QTc and change in urine albumin excretion (UAE) or progression of albuminuria in people with Type 2 diabetes.

METHODS

We measured QTc in 251 consecutive people at baseline. We performed a 5-year follow-up cohort study to assess the relationship between QTc and change in UAE, defined as an increase of UAE/follow-up duration (year), or progression of albuminuria, defined as an increase in the category of diabetic nephropathy.

RESULTS

During follow-up, 23 of 151 people with normoalbuminuria and 13 of 73 people with microalbuminuria at baseline had progression of albuminuria. Multiple regression analysis demonstrated that QTc was independently associated with change in UAE (β = 0.176, P = 0.0104). Logistic regression analyses showed that QTc was a risk marker for progression of albuminuria [odds ratio per 0.01-s increase in QTc 1.35, 95% confidence interval (CI) 1.11-1.66, P = 0.0024] after adjusting for confounders. According to the receiver operator characteristic (ROC) analysis, the optimal cut-off point of QTc for progression of albuminuria was 0.418 s [area under the ROC curve 0.75 (95% CI 0.66-0.82), sensitivity = 0.86, specificity = 0.56, P < 0.0001].

CONCLUSIONS

Heart rate-corrected QT interval could be a novel risk marker for progression of albuminuria in people with Type 2 diabetes.

Alterations in time intervals of ductus venosus and atrioventricular flow velocity waveforms in growth-restricted fetuses

OBJECTIVE

To investigate time intervals of the ductus venosus (DV) flow velocity waveform (FVW) and those of the cardiac cycle that correspond with each DV-FVW component in fetuses with intrauterine growth restriction (IUGR) due to placental insufficiency.

METHODS

Women with a pregnancy complicated by IUGR were recruited into the study, as was a normal control group. Time intervals for systolic (S) and diastolic (D) components were measured in DV-FVW as follows: S(DV), from the nadir of the a-wave during atrial contraction to the nadir between the S-wave and D-wave; D(DV), from the nadir between S-wave and D-wave to the nadir of the a-wave. Regarding cardiac cycles, the following variables were measured from ventricular inflow through the tricuspid valve (TV) and mitral valve (MV): S(TV) and S(MV), from the second peak of ventricular inflow caused by atrial contraction (A-wave) to the opening of the atrioventricular valve; D(TV) and D(MV), from the opening of the atrioventricular valve to the peak of the A-wave. In the IUGR group, only the last examination performed within 1 week of delivery was used for analysis. All variables were analyzed statistically using Z-scores.

RESULTS

Data were obtained from 249 normal fetuses and 26 fetuses with IUGR. Compared to normal fetuses, S(DV) showed a significant decrease (P < 0.001), while D(DV) showed a significant increase (P < 0.001) in the IUGR group. Regarding cardiac cycles, S(TV) and S(MV) showed significant decreases (P = 0.014 and P < 0.001, respectively) and D(TV) and D(MV) showed significant increases (P = 0.008 and P = 0.002, respectively) in fetuses with IUGR.

CONCLUSION

Time-interval alterations of DV-FVW in growth-restricted fetuses reflect the hemodynamic events caused by placental insufficiency.

Time-interval analysis of ductus venosus flow velocity waveforms in twin-to-twin transfusion syndrome treated with laser surgery

OBJECTIVES

To investigate time-interval variables of ductus venosus (DV) flow velocity waveforms (FVWs) in twin-to-twin transfusion syndrome (TTTS), comparing the results with reference ranges from normal singleton fetuses. The impact of laser surgery and the effect of prognostic factors were also evaluated.

METHODS

In 107 TTTS cases, DV-FVWs of both recipients and donors were recorded 1 day before and 2 days after laser therapy. Time intervals for systolic (S) and early diastolic (D) peaks were analyzed retrospectively with regard to acceleration time (acc-S and acc-D for S and D, respectively) and deceleration time (dec-S and dec-D for S and D, respectively). For each variable, Z-scores were calculated with respect to previously reported normal reference ranges.

RESULTS

Z-scores for all variables showed statistically significant differences from those observed previously in normal fetuses, with the exception of dec-S of donors. The most striking differences were observed in longer dec-S of recipients (P < 0.001) and longer dec-D of donors (P < 0.001). Laser therapy showed significant impact on dec-S and acc-D in recipients and on all variables in donors. Regarding the short-term prognosis, acc-S and dec-S showed significant differences for the prediction of intrauterine fetal demise in donors (P = 0.009 and P = 0.011, respectively).

CONCLUSION

This study demonstrates that time-interval variables of DV-FVWs may differentiate the characteristic hemodynamic changes caused by unbalanced blood volume between recipients and donors.