Stretch-induced compliance mechanism in pregnancy-induced cardiac hypertrophy and the impact of cardiovascular risk factors

Pressure overload-induced hypertrophy compromises cardiac stretch-induced compliance (SIC) after acute volume overload (AVO). We hypothesized that SIC could be enhanced by physiological hypertrophy induced by pregnancy's chronic volume overload. This study evaluated SIC-cardiac adaptation in pregnant women with or without cardiovascular risk (CVR) factors. Thirty-seven women (1st trimester, 1stT) and a separate group of 31 (3rd trimester, 3rdT) women [healthy or with CVR factors (obesity and/or hypertension and/or with gestational diabetes)] underwent echocardiography determination of left ventricular end-diastolic volume (LVEDV) and E/e' before (T0), immediately after (T1), and 15 min after (T2; SIC) AVO induced by passive leg elevation. Blood samples for NT-proBNP quantification were collected before and after the AVO. Acute leg elevation significantly increased inferior vena cava diameter and stroke volume from T0 to T1 in both 1stT and 3rdT, confirming AVO. LVEDV and E/e' also increased immediately after AVO (T1) in both 1stT and 3rdT. SIC adaptation (T2, 15 min after AVO) significantly decreased E/e' in both trimesters, with additional expansion of LVEDV only in the 1stT. NT-pro-BNP increased slightly after AVO but only in the 1stT. CVR factors, but not parity or age, significantly impacted SIC cardiac adaptation. A distinct functional response to SIC was observed between 1stT and 3rdT, which was influenced by CVR factors. The LV of 3rdT pregnant women was hypertrophied, showing a structural limitation to dilate with AVO, whereas the lower LV filling pressure values suggest increased diastolic compliance.NEW & NOTEWORTHY The sudden increase of volume overload triggers an acute myocardial stretch characterized by an immediate rise in contractility by the Frank-Starling mechanism, followed by a progressive increase known as the slow force response. The present study is the first to characterize echocardiographically the stretch-induced compliance (SIC) mechanism in the context of physiological hypertrophy induced by pregnancy. A distinct functional adaptation to SIC was observed between first and third trimesters, which was influenced by cardiovascular risk factors.

Prognostic value of flow-status in severe aortic stenosis patients undergoing percutaneous intervention

PURPOSE

Low-flow status is a mortality predictor in severe aortic stenosis (SAS) patients, including after transcatheter aortic valve implantation (TAVI) treatment. However, the best parameter to assess flow is unknown. Recent studies suggest that transaortic flow rate (FR) is superior to currently used stroke volume index (SVi) in defining low-flow states. Therefore, we aimed to evaluate the prognostic value of FR and SVi in patients undergoing TAVI.

METHODS

A single-centre retrospective analysis of all consecutive patients treated with TAVI for SAS between 2011 and 2019 was conducted. Low-FR was defined as < 200 mL/s and low-SVi as < 35 mL/m2. Primary endpoint was all-cause five-year mortality, analyzed using Kaplan-Meier curves and Cox regression models. Secondary endpoint was variation of NYHA functional class six months after procedure. Patients were further stratified according to ejection fraction (EF < 50%).

RESULTS

Of 489 cases, 59.5% were low-FR, and 43.1% low-SVi. Low-flow patients had superior surgical risk, worse renal function, and had a higher prevalence of coronary artery disease. Low-FR was associated with mortality (hazard ratio 1.36, p = 0.041), but not after adjustment to EuroSCORE II. Normal-SVi was not associated with survival, despite a significative p-trend for its continuous value. No associations were found for flow-status and NYHA recovery. When stratifying according to preserved and reduced EF, both FR and SVi did not predict all-cause mortality.

CONCLUSION

In patients with SAS undergoing TAVI, a low-FR state was associated with higher mortality, as well as SVi, but not at a 35 mL/m2 cut off.

Unsupervised clustering to differentiate rheumatoid arthritis patients based on proteomic signatures

OBJECTIVE

Patients with rheumatoid arthritis (RA) have different presentations and prognoses. Cluster analysis based on proteomic signatures creates independent phenogroups of patients with different pathophysiological backgrounds. We aimed to identify distinct pathophysiological clusters of RA patients based on circulating proteomic biomarkers.

METHOD

This was a cohort study including 399 RA patients. Clustering was performed on 94 circulating proteins (92 CVDII Olink®, high-sensitivity troponin T, and C-reactive protein). Unsupervised clustering was performed using a partitioning cluster algorithm.

RESULTS

The clustering algorithm identified two distinct clusters: cluster 1 (n = 223) and cluster 2 (n = 176). Compared with cluster 1, cluster 2 included older patients with a higher burden of comorbidities (cardiovascular and RA related), more erosive and longer RA duration, more dyspnoea and fatigue, walking a shorter distance in the Six-Minute Walk Test, with more severe diastolic dysfunction, and a 4.5-fold higher risk of death or hospitalization for cardiovascular reasons. Tumour necrosis factor (TNF) receptor superfamily-related pathways were mainly responsible for the model's discriminative ability.

CONCLUSION

Using unsupervised cluster analysis based on proteomic phenotypes, we identified two clusters of RA patients with distinct biomarkers profiles, clinical characteristics, and different outcomes that could reflect different pathophysiological backgrounds. TNF receptor superfamily-related proteins may be used to distinguish subgroups.

The Association between Gestational Diabetes and the Microbiome: A Systematic Review and Meta-Analysis

Gestational diabetes, affecting about 10% of pregnancies, is characterized by impaired glucose regulation and can lead to complications for health of pregnant women and their offspring. The microbiota, the resident microbes within the body, have been linked to the development of several metabolic conditions. This systematic review with meta-analysis aims to summarize the evidence on the differences in microbiota composition in pregnant women with gestational diabetes and their offspring compared to healthy pregnancies. A thorough search was conducted in the PubMed, Scopus, and Web of Science databases, and data from 21 studies were analyzed utilizing 41 meta-analyses. In the gut microbiota, Bifidobacterium and Alistipes were found to be more abundant in healthy pregnancies, while Roseburia appears to be more abundant in gestational diabetes. The heterogeneity among study findings regarding the microbiota in the meconium is considerable. The placental microbiota exhibited almost no heterogeneity, with an increased abundance of Firmicutes in the gestational diabetes group and a higher abundance of Proteobacteria in the control. The role of the microbiota in gestational diabetes is reinforced by these findings, which additionally point to the potential of microbiome-targeted therapies. To completely comprehend the interactions between gestational diabetes and the microbiome, standardizing methodologies and further research is necessary.

Diagnostic and monitoring applications using Near infrared (NIR) Spectroscopy in cancer and other diseases

Early cancer diagnosis plays a critical role in improving treatment outcomes and increasing survival rates for certain cancers. NIR spectroscopy offers a rapid and cost-effective approach to evaluate the optical properties of tissues at the microvessel level and provides valuable molecular insights. The integration of NIR spectroscopy with advanced data-driven algorithms in portable instruments has made it a cutting-edge technology for medical applications. NIR spectroscopy is a simple, non-invasive and affordable analytical tool that complements expensive imaging modalities such as functional magnetic resonance imaging, positron emission tomography and computed tomography. By examining tissue absorption, scattering, and concentrations of oxygen, water, and lipids, NIR spectroscopy can reveal inherent differences between tumor and normal tissue, often revealing specific patterns that help stratify disease. In addition, the ability of NIR spectroscopy to assess tumor blood flow, oxygenation, and oxygen metabolism provides a key paradigm for its application in cancer diagnosis. This review evaluates the effectiveness of NIR spectroscopy in the detection and characterization of disease, particularly in cancer, with or without the incorporation of chemometrics and machine learning algorithms. The report highlights the potential of NIR spectroscopy technology to significantly improve discrimination between benign and malignant tumors and accurately predict treatment outcomes. In addition, as more medical applications are studied in large patient cohorts, consistent advances in clinical implementation can be expected, making NIR spectroscopy a valuable adjunct technology for cancer therapy management. Ultimately, the integration of NIR spectroscopy into cancer diagnostics promises to improve prognosis by providing critical new insights into cancer patterns and physiology.

The impact of heart failure therapy in patients with mildly reduced ejection fraction: a network meta-analysis

BACKGROUND

Recent heart failure (HF) guidelines have re-classified HF patients with left ventricular ejection fraction (LVEF) between 41% and 49% as HF with mildly reduced ejection fraction (HFmrEF). HFmrEF treatment is often considered a grey zone as no randomized controlled trials (RCTs) were conducted exclusively on these patients.

AIMS

A network meta-analysis (NMA) was performed to compare treatment effect of mineralocorticoid receptor antagonists (MRA), angiotensin receptor neprilysin inhibitor (ARNi), angiotensin receptor blockers (ARB), angiotensin-converting-enzyme inhibitors (ACEi), sodium-glucose cotransporter-2 inhibitors (SGLT2i), and beta-blockers (BB) in HFmrEF cardiovascular (CV) outcomes.

METHODS AND RESULTS

RCTs sub-analyses evaluating the efficacy of pharmacological treatment in HFmrEF patients were searched. Hazard ratios (HRs) and their variance were extracted from each RCT for (i) composite of CV death or HF hospitalizations, (ii) CV death, and (iii) HF hospitalizations. A random-effects NMA was performed to compare and assess the treatment efficiency. Six RCTs with subgroup analysis according to participants' ejection fraction, a patient-level pooled meta-analysis of two RCTs, and an individual patient-level analysis of eleven BB RCTs were included, totalling 7966 patients. To our primary endpoint, SGLT2i vs. placebo was the only comparison with significant results, with a 19% risk reduction in the composite of CV death or HF hospitalizations [HR 0.81, 95% confidence interval (CI) 0.67-0.98]. In HF hospitalizations, the impact of the pharmacological therapies was more notorious, and ARNi reduced in 40% the risk of HF hospitalizations (HR 0.60, 95% CI 0.39-0.92), SGLT2i in 26% (HR 0.74, 95% CI 0.59-0.93) and renin-angiotensin system inhibition (RASi) with ARB and ACEi in 28% (HR 0.72, 95% CI 0.53-0.98). Although BBs were globally less beneficial, they were the only class that supported a reduced risk of CV death (HR vs. placebo: 0.48, 95% CI 0.24-0.95). We did not observe a statistically significant difference in any comparison between active treatments. There was a sound reduction with ARNi on the primary endpoint (HR vs. BB: 0.81, 95% CI 0.47-1.41; HR vs. MRA 0.94, 95% CI 0.53-1.66) and on HF hospitalizations (HR vs. RASi 0.83, 95% CI 0.62-1.11; HR vs. SGLT2i 0.80, 95% CI 0.50-1.30).

CONCLUSIONS

In addition to SGLT2i, pharmacological treatment recommended for HF with reduced LVEF, namely, ARNi, MRA, and BB, can also be effective in HFmrEF. This NMA did not show significant superiority over any pharmacological class.

Higher coronary artery calcium score is associated with increased risk of atrial fibrillation recurrence after catheter ablation

BACKGROUND

Coronary artery calcium score (CACS) is associated with an increased risk of atrial fibrillation (AF) development, but scarce data are available regarding the impact on AF recurrence. This study aims to assess the impact of CACS on AF recurrence following catheter ablation.

METHODS

Retrospective study of patients with AF undergoing cardiac computed tomography (CCT) before ablation (2017-2019). Patients with coronary artery disease (CAD), significant valvular heart disease and previous catheter ablation were excluded. A cut-off of CACS ≥ 100 was used according to literature.

RESULTS

A total of 311 patients were included (median age 57 [48, 64] years, 65% men and 21% with persistent AF). More than half of the patients had a CACS > 0 (52%) and 18% a CACS ≥ 100. Patients with CACS ≥ 100 were older (64 [59, 69] vs 55 [46, 63] years, p ​< ​0.001), had more frequently hypertension (68% vs 42%, p ​< ​0.001) and diabetes mellitus (21% vs 10%, p ​= ​0.020). During a median follow-up of 34 months (12-57 months), 98 patients (32%) had AF recurrence. CACS ≥ 100 was associated with increased risk of AF recurrence (unadjusted Cox regression: hazard ratio [HR] 2.0; 95% confidence interval [CI], 1.3-3.1, p ​= ​0.002). After covariate adjustment, CACS ≥ 100 and persistent AF remained independent predictors of AF recurrence (HR, 1.7; 95% CI, 1.0-2.8, p ​= ​0.039 and HR, 2.0; 95% CI, 1.3-3.2, p ​= ​0.004, respectively).

CONCLUSION

An opportunistic evaluation of CACS could be an important tool to improve clinical care considering that CACS ≥ 100 was independently associated with a 69% increase in the risk of AF recurrence after first catheter ablation.

Clinical relevance of the blanking period on late recurrence after catheter ablation of atrial fibrillation

INTRODUCTION

Recurrence of atrial fibrillation (AF) within the blanking period after catheter ablation (CA) is traditionally classified as a transient and benign event. However, recent findings suggest that early recurrence (ER) is associated with late recurrence (LR), challenging the predefined "blanking period". We aimed to determine the clinical and procedural predictors of ER and LR after CA and establish the risk of LR in patients who experience ER.

METHODS AND RESULTS

Retrospective single-centre study including all patients who underwent a first procedure of AF CA between 2017 and 2019. ER was defined as any recurrence of AF, atrial flutter or atrial tachycardia >30 s within 90 days after CA and LR as any recurrence after 90 days of CA. A total of 399 patients were included, 37% women, median age of 58 years [49-66] and 77% had paroxysmal AF. Median follow-up was 33 months (from 13 to 61). ER after CA was present in 14% of the patients, and LR was reported in 32%. Among patients who experienced ER, 84% also had LR (p < .001). Patients with ER had a higher prevalence of moderate/severe valvular heart disease, persistent AF, previous electrical cardioversion, a larger left atrium, higher coronary artery calcium score, and higher rates of intraprocedural electrical cardioversion and cardiac fibrosis on eletroanatomical mapping compared with patients without ER. After covariate adjustment, ER and female sex were defined as independent predictors of LR (hazard ratio [HR] 4.69; 95% confidence interval [CI], 2.99-7.35; p < .001 and HR 2.73; 95% CI, 1.47-5.10; p = .002, respectively).

CONCLUSION

The risk of LR after an index procedure of CA was significantly higher in patients with ER (five-fold increased risk). These results support the imperative need to clarify the clinical role of the blanking period.

Epicardial adipose tissue volume is not an independent predictor of atrial fibrillation recurrence after catheter ablation

INTRODUCTION AND OBJECTIVES

Previous studies have suggested that epicardial adipose tissue (EAT) could exert a paracrine effect in the myocardium. However, few studies have assessed its role in the risk of atrial fibrillation (AF) recurrence. This study aimed to evaluate the association between EAT volume, and its attenuation, with the risk of AF recurrence after AF ablation.

METHODS

A total of 350 consecutive patients who underwent AF ablation were included. The median age was 57 [IQR 48-65] years and 21% had persistent AF. Epicardial fat was quantified by multidetector computed tomography using Syngo.via Frontier-Cardiac Risk Assessment software, measuring pericardial fat volume (PATV), EAT volume, and attenuation of EAT posterior to the left atrium. AF recurrence was defined as any documented episode of AF, atrial flutter, or atrial tachycardia more than 3 months after the procedure.

RESULTS

After a median follow-up of 34 [range, 12-57] months, 114 patients (33%) had AF recurrence. Univariable Cox regression showed that patients with an EAT volume ≥ 80mL had an increased risk of AF recurrence (HR, 1.65; 95%CI, 1.14-2.39; P=.007). However, after multivariable adjustment, EAT volume did not remain an independent predictor of AF recurrence (HR, 1.24; 95%CI, 0.83-1.87; P=.3). Similar results were observed with PATV. Patients with lower attenuation of EAT did not have a higher risk of AF recurrence (log-rank test, P=.75).

CONCLUSIONS

EAT parameters including the evaluation of EAT volume, PATV and EAT attenuation were not independent predictors of AF recurrence after catheter ablation.

Aortic Valve Surgery in Patients with Infective Endocarditis: Mid-Term Follow-up of Patients Treated With the ST. Jude Medical Trifecta Valve

BACKGROUND

It is particularly difficult to choose the appropriate prosthesis to treat infective endocarditis.

OBJECTIVES

To investigate the outcomes after aortic valve replacement with a stented bioprosthesis (Trifecta) in patients with active or previous infective endocarditis.

METHODS

We performed a single-centre, retrospective study including consecutive patients with infective endocarditis who underwent aortic valve replacement between July 2011 and June 2019. Survival and reintervention were assessed as of December 2021. Hospital mortality was defined as death in-hospital or within 30-days of surgery. Kaplan-Meier method was used for time-to-event outcome assessment (all-cause mortality and reoperation). Data are median (minimum and maximum) or absolute (relative) frequencies.

RESULTS

We included 51 patients, median age of 69 (40 to 87) years, 78% male. The median follow-up time was 5.4 years and the maximum was 10 years. Most patients (71%) had native valve infective endocarditis and 16% had previous endocarditis. Surgery was urgent in 82%. Hospital mortality occurred in 10 patients (20%). After excluding these patients, 1-, 3-, 6-, and 9-years cumulative survival rates were 93%, 78%, 72%, and 72%, respectively. There were five bioprosthesis-related reoperations: 4 due to endocarditis at 1-year, 3-years, and 5-years on follow-up (n=1, 1 and 2, respectively) and 1 due to non-structural deterioration, 6-years after surgery.

CONCLUSIONS

Despite the small sample size, this report supports a satisfactory performance profile of the Trifecta bioprosthesis in the treatment of infective endocarditis.

Interleukin-6, infection and cardiovascular outcomes in acute heart failure: Findings from the EDIFICA registry

AIMS

Interleukin-6 (IL-6) is upregulated in response to infectious and inflammatory triggers and independently predicts all-cause mortality in acute heart failure (AHF). However, the association of IL-6 with cardiovascular outcomes and its interplay with C-reactive protein and infection, a major precipitating factor in AHF, remains poorly understood.

METHODS AND RESULTS

The association between IL-6 and clinical outcomes (180 days) in AHF was evaluated using a cohort of 164 patients from the EDIFICA registry. Median IL-6 levels at admission were 17.4 pg/mL. Patients in the higher admission IL-6 tertile presented with lower blood pressure and more congestion, were diagnosed more frequently with infection, and had a longer hospital stay. Higher IL-6 levels were associated with increased risk of HF rehospitalization (hazard ratio per log₂ 3.69, 95% confidence interval (CI) 1.26-10.8, p =.017) and the composite of HF rehospitalization or cardiovascular death (hazard ratio per log₂ 3.50; 95% CI 1.28-9.57; p =.014), independently of major AHF prognosticators, including B-type natriuretic peptide and renal function. However, no independent associations were found for all-cause rehospitalization or mortality. Despite a moderate correlation of IL-6 with C-reactive protein (CRP) levels (R = .51), the latter were not associated with clinical outcomes in this population.

CONCLUSIONS

IL-6 levels associate with higher rate of cardiovascular events in AHF, independently of classical prognosticators and evidence of infection, outperforming CRP as an inflammatory outcome biomarker.

Metabolic profiling of induced acute pancreatitis and pancreatic cancer progression in a mutant Kras mouse model

Untargeted Nuclear Magnetic Resonance (NMR) metabolomics of polar extracts from the pancreata of a caerulin-induced mouse model of pancreatitis (Pt) and of a transgenic mouse model of pancreatic cancer (PCa) were used to find metabolic markers of Pt and to characterize the metabolic changes accompanying PCa progression. Using multivariate analysis a 10-metabolite metabolic signature specific to Pt tissue was found to distinguish the benign condition from both normal tissue and precancerous tissue (low grade pancreatic intraepithelial neoplasia, PanIN, lesions). The mice pancreata showed significant changes in the progression from normal tissue, through low-grade and high-grade PanIN lesions to pancreatic ductal adenocarcinoma (PDA). These included increased lactate production, amino acid changes consistent with enhanced anaplerosis, decreased concentrations of intermediates in membrane biosynthesis (phosphocholine and phosphoethanolamine) and decreased glycosylated uridine phosphates, reflecting activation of the hexosamine biosynthesis pathway and protein glycosylation.

Frailty-Independent Undertreatment Negative Impact on Survival in Older Patients With Breast Cancer

Purpose

The management of older adults with breast cancer (BC) remains controversial. The challenging assessment of aging idiosyncrasies and the scarce evidence of therapeutic guidelines can lead to undertreatment. Our goal was to measure undertreatment and assess its impact on survival.

Methods

Consecutive patients with BC aged 70 years or older were prospectively enrolled in 2014. Three frailty screening tools (G8, fTRST, and GFI) and two functional status scales (Karnofsky performance score and Eastern Cooperative Oncology Group Performance Status) were applied. Disease characteristics, treatment options, and causes of mortality were recorded during a 5-year follow-up. In addition, we defined undertreatment and correlated its survival impact with frailty.

Results

A total of 92 patients were included in the study. The median age was 77 (range 70–94) years. The prevalence of frailty was discordant (G8, 41.9%; fTRST, 74.2%; GFI, 32.3%). Only 47.8% of the patients had a local disease, probably due to a late diagnosis (73.9% based on self-examination). Thirty-three patients (35.6%) died, of which 15 were from BC. We found a considerably high proportion (53.3%) of undertreatment, which had a frailty-independent negative impact on the 5-year survival (hazard ratio [HR], 5.1; 95% confidence interval [CI], 2.1–12.5). Additionally, omission of surgery had a frailty-independent negative impact on overall survival (HR, 3.9; 95% CI, 1.9–7.9).

Conclusion

BC treatment in older adults should be individualized. More importantly, assessing frailty (not to treat) is essential to be aware of the risk-benefit profile and the patient's well-informed willingness to be treated. Undertreatment in daily practice is frequent and might have a negative impact on survival, as we report.

Pseudo-patella baja after total knee arthroplasty: Radiological evaluation and clinical repercussion

BACKGROUND

Anterior knee pain is an important complication after total knee arthroplasty (TKA). One possible contributor is the elevation of the joint line, known as pseudo-patella baja (PPB). Limited research has been conducted regarding this condition impacting TKA management. This study aims to evaluate the incidence, identify possible related factors and assess PPB clinical repercussions.

METHODS

A total of 813 consecutive TKAs were retrospectively reviewed. Patients were submitted to the same surgical procedure and information regarding TKA characteristics was collected. Lateral postoperative knee radiographs were analyzed using the modified Insall-Salvati Ratio and the Blackburne-Peel Index. A clinical evaluation was conducted on 112 knees where the Oxford Knee and Kujala Scores were applied. Range of motion was evaluated, and knee pain was assessed using the numeric pain rating scale, in addition to analgesic consumption.

RESULTS

A cohort of 612 knees was analyzed, of which 64 knees developed PPB (10.5% incidence). Statistically significant differences were found for advance components sizes (femoral P = 0.026 and tibial P < 0.001), polyethylene thickness (P < 0.001) and patients' height (P = 0.022) with smaller implant sizes, greater insert thicknesses and lower height showing an association with PPB. The PPB group had a significantly lower median Kujala score (P = 0.011), higher frequency of flexion contracture and of anterior knee pain (P = 0.039).

CONCLUSION

PPB has a clinical relevance that should not be overlooked. Its prevention through the recreation of the natural position of the joint line and correct choice of implant sizes and polyethylene thickness is of major importance and should always be considered.

A systematic review and meta-analysis of randomized controlled studies comparing off-pump versus on-pump coronary artery bypass grafting in the elderly

AIM

Comparison of short and mid-term outcomes between off-pump CABG (OPCAB) and on-pump CABG (ONCAB) in patients older than 65 throughout a meta-analysis of randomized clinical trials (RCTs).

EVIDENCE ACQUISITION

A literature search was conducted using 3 databases. RCTs reporting mortality outcomes of OPCAB versus ONCAB among the elderly were included. Data on myocardial infarction, stroke, re-revascularization, renal failure and composite endpoints after CABG were also collected. Random effects models were used to compute statistical combined measures and 95% confidence intervals (CI).

EVIDENCE SYNTHESIS

Five RCTs encompassing 6221 patients were included (3105 OPCAB and 3116 ONCAB). There were no significant differences on mid-term mortality (pooled HR: 1.02, 95%CI: 0.89-1.17, p=0.80) and composite endpoint incidence (pooled HR: 0.98, 95%CI: 0.88-1.09, p=0.72) between OPCAB and ONCAB. At 30-day, there were no differences in mortality, myocardial infarction, stroke and renal complications. The need for early re-revascularization was significantly higher in OPCAB (pooled OR: 3.22, 95%CI: 1.28-8.09, p=0.01), with a higher percentage of incomplete revascularization being reported for OPCAB in trials included in this pooled result (34% in OPCAB vs 29% in ONCAB, p<0.01).

CONCLUSIONS

Data from RCTs in elderly patients showed that OPCAB and ONCAB provide similar mid-term results. OPCAB was associated with a higher risk of early rerevascularization. As CABG on the elderly is still insufficiently explored, further RCTs, specifically designed targeting this population, are needed to establish a better CABG strategy for these patients.

Off-pump versus on-pump coronary artery bypass grafting: a propensity score-matching analysis of safety and long-term results

Background

The role and the indications for using off-pump coronary artery bypass surgery (OPCAB), instead of the traditional on-pump (ONCAB), is still to be addressed.

Aim

To describe our centre experience and to compare 15-years survival and early safety outcomes between OPCAB and ONCAB.

Methods

Single-centre retrospective cohort including 9-years of isolated first CABG (2005–2013). Multi-vessel disease with at least 2 surgical grafts patients were considered and the first 50 surgeries of each surgeon with each technique were excluded to account for the learning curve effect. Emergent surgeries and on-pump beating heart procedures were also excluded. A propensity-score matching (PSM) analysis was performed to balance groups and both survival and early outcomes comparison was done within the matched cohort using Kaplan-Meier or Cox stratified and paired tests, respectively. The median follow-up was 9 years, maximum 15 years.

Results

From 3012 multi-vessel patients with at least 2 surgical grafts, 2503 were included at the main analysis: 1487 ONCAB and 1016 OPCAB. ONCAB patients presented more frequently 3-vessels disease and left ventricular dysfunction, but received similar number of grafts than OPCAB, who in turn, received more frequently multiple arterial grafts. The surgical completeness of revascularization (CR) was similar, but hybrid procedures were more frequent in OPCAB raising CR rate in this group. After PSM (646 pairs), both groups were similar regarding pre and peri-operative characteristics. The long-term survival was similar (HR stratified by pair: 1.02 (0.81–1.30), but OPCAB evidenced benefits at early term results including bleeding, postoperative atrial fibrillation and stroke incidence.

Conclusion

At our centre, OPCAB performed by experienced surgeons provides rates of complete revascularization and long-term survival similar to ONCAB. In-hospital results favoured OPCAB.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): Universidade do Porto/FMUP; Social European Fund; FCT-Fundação para a Ciência e a Tecnologia

A meta-analysis of randomized controlled studies comparing off-pump vs on-pump CABG in the elderly

Background

The increasing demand for coronary revascularization in the elderly has raised the interest in off-pump coronary artery bypass graft (CABG) as an option in these high-risk patients.

Purpose

We sought to investigate the differences between off-pump CABG (OPCAB) and on-pump CABG (ONCAB), among patients older than 60, in short and mid-term results throughout a meta-analysis of randomized clinical trials (RCTs).

Methods

A literature search was conducted using MEDLINE, ISI Web of Science and Cochrane Library (1960–2020). RCTs reporting mortality outcomes of OPCAB vs ONCAB within elderly patients (as prespecified or secondary analysis) were included. Data on myocardial infarction, stroke, repeat revascularization, renal failure and composite endpoints after CABG were also collected. Hazard ratio (HR) and variance for follow-up outcomes and frequencies or odds ratio (OR) for early endpoints were collected. Random effect models were used to compute statistical combined measures and 95% confidence intervals (CI).

Results

Seven RCTs encompassing a total of 6,609 patients were included (3,303 OPCAB and 3,306 ONCAB, 50% were men). Five trials reported mortality during follow-up (6 months (2 studies) to 5 years). There were no significant differences on mid-term mortality (pooled HR: 1.02, 95% CI: 0.88–1.17, p=0.82) and composite endpoint incidence (4 studies pooled HR: 0.98, 95% CI: 0.88–1.09, p=0.73) between OPCAB and ONCAB. At 30-days, no differences between groups were noted in mortality (5 studies pooled OR: 0.90, 95% CI: 0.62–1.31, p=0.59), early myocardial infarction (5 studies pooled OR: 0.95, 95% CI: 0.60–1.51, p=0.82) and renal complications (3 studies pooled OR: 0.74, 95% CI: 0.50–1.11, p=0.14). The need for early repeat revascularization was significantly higher in OPCAB (2 studies pooled OR: 2.58, 95% CI: 1.16–5.75, p=0.02), with higher percentage of incomplete revascularization among OPCAB in both trials included in this pooled result (34% in OPCAB vs 29% in ONCAB, p&lt;0.01). However, OPCAB showed a tendency for lower risk of early stroke (6 studies pooled OR: 0.70, 95% CI: 0.48–1.03, p=0.07).

Conclusions

Pooling data from RCTs in elderly patients showed that OPCAB and ONCAB provide similar mid-term results. However, OPCAB was associated with a higher risk of early repeat revascularization and there was a trend for reduced early stroke risk. Further randomized studies, specifically designed to include elderly patients, are needed to establish the better CABG strategy.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): Universidade do Porto/FMUP and FSE-Social European Fund; Fundação para a Ciência e Tecnologia Early and Mid-term Results

Multiple versus single arterial grafting in the elderly: a meta-analysis of randomized controlled trials and propensity score studies

INTRODUCTION

The benefit of adding a second arterial conduit is still controversial, mainly in specific subgroups. We conducted a meta-analysis of randomized controlled trials (RCTs) and propensity score (PS) studies comparing survival and early results in elderly patients who underwent coronary artery bypass grafting (CABG) with multiple (MAG) versus single arterial grafting (SAG).

EVIDENCE ACQUISITION

MEDLINE, Web of Science and Cochrane Library were used to find relevant literature (1960-April 2020). Survival at a ≥ 1-year follow-up and early outcomes were evaluated. Outcomes were collected from matched samples or PS adjusted analysis: hazard ratio (HR) along with their variance, frequencies or odds ratios. Random effect models were used to compute combined statistical measures and 95% confidence intervals (CI) through generic inverse variance method (time-to-event) or Mantel-Haenszel method (binary events).

EVIDENCE SYNTHESIS

Eleven PS cohorts and 1 RCT comprising > 18,800 patients older than 70 (>6200 MAG and >12,500 SAG) were included in this meta-analysis. MAG was associated with lower long-term mortality (pooled HR: 0.81, 95%CI: 0.72-0.91, p<0.01, I2=64%) in the absence of higher risk of early mortality (pooled OR: 0.74, 95%CI: 0.44 to 1.25, p=0.27, I2=0%). In a meta-regression, MAG survival advantage was more pronounced in studies with a higher MAG usage rate (β = -0.0052, p=0.021).

CONCLUSIONS

Current evidence suggests that advanced age should not limit MAG's use considering its benefits in long-term survival. Of note, an individualized patient selection for this approach is warranted.

Assessing the influence of perfusion on cardiac microtissue maturation: A heart-on-chip platform embedding peristaltic pump capabilities

Heart‐on‐chip is an unprecedented technology for recapitulating key biochemical and biophysical cues in cardiac pathophysiology. Several designs have been proposed to improve its ability to mimic the native tissue and establish it as a reliable research platform. However, despite mimicking one of most vascularized organs, reliable strategies to deliver oxygen and substrates to densely packed constructs of metabolically demanding cells remain unsettled. Herein, we describe a new heart‐on‐chip platform with precise fluid control, integrating an on‐chip peristaltic pump, allowing automated and fine control over flow on channels flanking a 3D cardiac culture. The application of distinct flow rates impacted on temporal dynamics of microtissue structural and transcriptional maturation, improving functional performance. Moreover, a widespread transcriptional response was observed, suggesting flow‐mediated activation of critical pathways of cardiomyocyte structural and functional maturation and inhibition of cardiomyocyte hypoxic injury. In conclusion, the present design represents an important advance in bringing engineered cardiac microtissues closer to the native heart, overcoming traditional bulky off‐chip fluid handling systems, improving microtissue performance, and matching oxygen and energy substrate requirements of metabolically active constructs, avoiding cellular hypoxia. Distinct flow patterns differently impact on microtissue performance and gene expression program.

Mining the Biomarker Potential of the Urine Peptidome: From Amino Acids Properties to Proteases

Native biofluid peptides offer important information about diseases, holding promise as biomarkers. Particularly, the non-invasive nature of urine sampling, and its high peptide concentration, make urine peptidomics a useful strategy to study the pathogenesis of renal conditions. Moreover, the high number of detectable peptides as well as their specificity set the ground for the expansion of urine peptidomics to the identification of surrogate biomarkers for extra-renal diseases. Peptidomics further allows the prediction of proteases (degradomics), frequently dysregulated in disease, providing a complimentary source of information on disease pathogenesis and biomarkers. Then, what does urine peptidomics tell us so far? In this paper, we appraise the value of urine peptidomics in biomarker research through a comprehensive analysis of all datasets available to date. We have mined > 50 papers, addressing > 30 different conditions, comprising > 4700 unique peptides. Bioinformatic tools were used to reanalyze peptide profiles aiming at identifying disease fingerprints, to uncover hidden disease-specific peptides physicochemical properties and to predict the most active proteases associated with their generation. The molecular patterns found in this study may be further validated in the future as disease biomarker not only for kidney diseases but also for extra-renal conditions, as a step forward towards the implementation of a paradigm of predictive, preventive and personalized (3P) medicine.

Urocortin-2 in Acute Heart Failure: Role as a Marker of Volume Overload and Pulmonary Hypertension

Urocortin (Ucn)-2 has shown promising therapeutic effects on heart failure (HF). However, there are still significant knowledge gaps regarding the role and modulation of the endogenous Ucn-2 axis in the cardiovascular system and, specifically, in acute HF. We evaluated Ucn-2 levels in admission serum samples of 80 acute HF patients and assessed their association with clinical, analytical and echocardiographic parameters. Median age was 76.5 years, and 37 patients (46%) were male. Median serum Ucn-2 was 2.3ng/mL. Ucn-2 levels were positively associated with peripheral edemas (P = 0.022), hepatomegaly (P = 0.007) and sodium retention score (ρ = 0.37, P = 0.001) and inversely correlated with inferior vena cava collapse at inspiration (ρ = -0.37, P = 0.001). Additionally, patients with higher Ucn-2 levels had a higher prevalence of right atrial dilation (P = 0.027), right ventricle dilation (P = 0.008), and higher systolic pulmonary artery pressure (ρ = 0.34, P = 0.002). Regarding analytical parameters, Ucn-2 correlated positively with log BNP (r = 0.22, P = 0.055) and inversely with uric acid (r = 0.24, P = 0.029) and total (r = -0.30, P = 0.007) and low-density lipoprotein cholesterol (r = -0.23, P = 0.038). No associations were found between Ucn-2 and age, sex or left heart structure or function. In conclusion, Circulating Ucn-2 was associated with clinical and echocardiographic markers of volume overload and pulmonary hypertension in acute HF patients.

Prevalence, risk factors and proteomic bioprofiles associated with heart failure in rheumatoid arthritis: The RA-HF study

BACKGROUND

Rheumatoid arthritis (RA) patients have high risk of heart failure (HF).

AIMS

Identifying the risk factors and mechanistic pathways associated with HF in patients with RA.

METHODS

Cohort study enrolling 355 RA patients. HF was defined according to the ESC criteria. 93 circulating protein-biomarkers (91CVDIIOlink®+troponin-T+c-reactive protein) were measured. Regression modeling (multivariate and multivariable) were built and network analyses were performed - based on the identified relevant protein biomarkers.

RESULTS

115 (32.4%) patients fulfilled the ESC criteria for HF, but only 24 (6.8%) had a prior HF diagnosis. Patients with HF were older (67 vs. 55yr), had a longer RA duration (10 vs. 14yr), had more frequently diabetes, hypertension, obesity, dyslipidemia, atrial fibrillation, and ischemic arterial disease. Several protein-biomarkers remained independently associated with HF, the top (FDR1%) were adrenomedullin, placenta-growth-factor, TNF-receptor-11A, and angiotensin-converting-enzyme-2. The networks underlying the expression of these biomarkers pointed towards congestion, apoptosis, inflammation, immune system signaling and RAAS activation as central determinants of HF in RA. Similar HF-associated biomarker-pathways were externally found in patients without RA. Having RA plus HF increased the risk of cardiovascular events compared to RA patients without RF; adjusted-HR (95%CI)=2.37 (1.07-5.30), p=0.034 CONCLUSION: Age, cardiovascular risk factors, and RA duration increase the HF odds in patients with RA. Few RA patients had a correct prior HF diagnosis, but the presence of HF increased the patients` risk. RA patients with HF largely share the mechanistic pathways of HF patients without RA. Randomized HF trials should include patients with RA. CLINICALTRIALS.

GOV ID

NCT03960515.

Exosome-Derived Mediators as Potential Biomarkers for Cardiovascular Diseases: A Network Approach

Cardiovascular diseases (CVDs) are widely recognized as the leading cause of mortality worldwide. Despite the advances in clinical management over the past decades, the underlying pathological mechanisms remain largely unknown. Exosomes have drawn the attention of researchers for their relevance in intercellular communication under both physiological and pathological conditions. These vesicles are suggested as complementary prospective biomarkers of CVDs; however, the role of exosomes in CVDs is still not fully elucidated. Here, we performed a literature search on exosomal biogenesis, characteristics, and functions, as well as the different available exosomal isolation techniques. Moreover, aiming to give new insights into the interaction between exosomes and CVDs, network analysis on the role of exosome-derived mediators in coronary artery disease (CAD) and heart failure (HF) was also performed to incorporate the different sources of information. The upregulated exosomal miRNAs miR-133a, miR-208a, miR-1, miR-499-5p, and miR-30a were described for the early diagnosis of acute myocardial infarction, while the exosome-derived miR-192, miR-194, miR-146a, and miR-92b-5p were considered as potential biomarkers for HF development. In CAD patients, upregulated exosomal proteins, including fibrinogen beta/gamma chain, inter-alpha-trypsin inhibitor heavy chain, and alpha-1 antichymotrypsin, were assessed as putative protein biomarkers. From downregulated proteins in CAD patients, albumin, clusterin, and vitamin D-binding protein were considered relevant to assess prognosis. The Vesiclepedia database included miR-133a of exosomal origin upregulated in patients with CAD and the exosomal miR-192, miR-194, and miR-146a upregulated in patients with HF. Additionally, Vesiclepedia included 5 upregulated and 13 downregulated exosomal proteins in patients in CAD. The non-included miRNAs and proteins have not yet been identified in exosomes and can be proposed for further research. This report highlights the need for further studies focusing on the identification and validation of miRNAs and proteins of exosomal origin as biomarkers of CAD and HF, which will enable, using exosomal biomarkers, the guiding of diagnosis/prognosis in CVDs.

Influence of EPICardial adipose tissue in HEART diseases (EPICHEART) study: Protocol for a translational study in coronary atherosclerosis

INTRODUCTION

Accumulation of epicardial adipose tissue (EAT) is associated with coronary artery disease (CAD) and increased risk of coronary events in asymptomatic subjects and low-risk patients, suggesting that EAT promotes atherosclerosis in its early stage. Recent studies have shown that the presence of CAD affects the properties of adjacent EAT, leading to dynamic changes in the molecular players involved in the interplay between EAT and the coronary arteries over the history of the disease. The role of EAT in late-stage CAD has not been investigated.

OBJECTIVES

In a comparative analysis with mediastinal and subcutaneous adipose tissue, we aim to investigate whether the volume of EAT assessed by computed tomography and its proteome assessed by SWATH-MS mass spectrometry are associated with late stages of CAD in an elderly cohort of severe aortic stenosis patients.

METHODS

The EPICHEART study (NCT03280433) is a prospective study enrolling patients with severe degenerative aortic stenosis referred for elective aortic valve replacement, whose protocol includes preoperative clinical, nutritional, echocardiographic, cardiac computed tomography and invasive coronary angiographic assessments. During cardiac surgery, samples of EAT and mediastinal and subcutaneous thoracic adipose tissue are collected for proteomics analysis by SWATH-MS. In addition, pericardial fluid and peripheral and coronary sinus blood samples are collected to identify circulating and local adipose tissue-derived biomarkers of CAD.

CONCLUSION

We designed a translational study to explore the association of EAT quantity and quality with advanced CAD. We expect to identify new biochemical factors and biomarkers in the crosstalk between EAT and the coronary arteries that are involved in the pathogenesis of late coronary atherosclerosis, especially coronary calcification, which might be translated into new therapeutic targets and imaging tools by biomedical engineering.

Early And Midterm Outcomes Following Aortic Valve Replacement With Mechanical Versus Bioprosthetic Valves In Patients Aged 50 To 70 Years

OBJECTIVES

To compare 7-year survival and freedom from reoperation, as well as early clinical and hemodynamic outcomes, after surgical aortic valve replacement (SAVR) with mechanical or bioprosthetic valves in patients aged 50-70 years.

METHODS

single-center retrospective cohort study including adults aged 50-70 years who underwent SAVR in 2012 with a mechanical or bioprosthetic valve. Median follow-up was 7 years. Univariable analyses were performed using Kaplan-Meier curves and Log-Rank tests for survival and freedom from reoperation analyses. Multivariable time-to-event analyses were conducted using Cox Regression.

RESULTS

Of a total of 193 patients, 76 (39.4%) received mechanical valves and 117 (60.6%) received bioprosthetic valves. A trend for better survival was found for mechanical prostheses when adjusting for EuroSCORE II (HR: 0.35; 95%CI: 0.12-1.02, p=0.054), but using a backward stepwise Cox regression prosthesis type was not retained by the model as an independent predictor of survival. Moreover, mechanical prostheses showed trends for higher freedom from reoperation (100% vs. 95.5%, Log-Rank, p=0.076), higher median EuroSCORE II (2.52% vs. 1.95%, p=0.06) and early mortality (7.9% vs. 2.6%, p=0.086). However, after adjusting for EuroSCORE II, there was no significant difference in early mortality (OR: 2.3, 95%CI: 0.5-10.5, p=0.272). Regarding hemodynamic performance at follow-up echocardiogram, there were no differences other than left ventricular mass regression, which was not as pronounced in the mechanical group (-12% vs. -21%, p=0.002).

CONCLUSION

Mechanical and bioprosthetic aortic valves prostheses showed similar mid-term survival in the 50-70 age group. Further prospective and larger studies are needed to provide evidence-based recommendations on this topic.

P4643Pulmonary hypertension incidence is higher than systemic arterial hypertension in children after aortic coarctation repair

Introduction

Coarctation of the aorta (CoA) is characterized by diffuse arteriopathy which can persist to upward of the aortic isthmus, even after successful surgical correction. This arteriopathy can also occur in the pulmonary vasculature, leading to pulmonary hypertension (PH), a strong risk factor of poor prognosis in CoA population.

Purpose

The purpose of this study was to determine the incidence of systemic and pulmonary hypertension in a CoA paediatric population after surgical repair, as well as the impact of PH in right ventricular function.

Methods

This cross-sectional study included children after successful surgical repair of the CoA in a tertiary centre [1996, 2009] up to the first year of age. Children with other cardiac structural lesions or recoarctation were excluded. Systemic arterial hypertension was defined as blood pressure in the 95th percentile or higher. PH was considered if the estimated pulmonary systolic arterial pressure (PSAP) was higher than 30mmHg. Pulse wave velocity, ambulatory 24 hours blood pressure monitoring, echocardiographic assessment of right ventricle (RV) and blood tests were performed 11±4 years after surgical procedure. Echocardiographic variables were normalized and evaluated by z-scores. One sample t test or sign test was used to estimate the deviation of measured/observed values from the normality/expected values (defined by z-score=0).

Results

We included 38 children with a mean age of 12±4 years (63% male). Late arterial hypertension was diagnosed in 29% of the children and PH incidence was 68% with a mean PSAP of 37±5mmHg. The mean of A' wave (z-score: 0.34±0.93, p=0.030) and median of E/E' ratio (z-score: 0.46 [−1.32; 3.68], p=0.004) z-scores were increased comparing with expected normal values in paediatric population. Moreover, E' wave (z-score: −0.35±0.98, p=0.034) and RV index of myocardial performance (z-score: −0.20±0.41, p=0.006) were decreased. Regarding RV systolic function, TAPSE z-score was significantly increased (z-score: 2.06±2.33, p<0.001), being outside the z-score normal range.

Conclusion

Children submitted to CoA surgical repair before the first year of life showed a higher PH incidence than late systemic hypertension occurrence. Also, they already present with significant RV functional abnormalities when compared to the normal paediatric population. These abnormalities can underlie pulmonary vascular remodelling after left ventricular pressure overload in CoA population that seems irreversible after pressure overload relief.

Acknowledgement/Funding

AFF are supported by FCT (SFRH/BD/138925/2018)

Urine Nuclear Magnetic Resonance (NMR) Metabolomics in Age-Related Macular Degeneration

Biofluid biomarkers of age-related macular degeneration (AMD) are still lacking, and their identification is challenging. Metabolomics is well-suited to address this need, and urine is a valuable accessible biofluid. This study aimed to characterize the urinary metabolomic signatures of patients with different stages of AMD and a control group (>50 years). It was a prospective, cross-sectional study, where subjects from two cohorts were included: 305 from Coimbra, Portugal (AMD patients n = 252; controls n = 53) and 194 from Boston, United States (AMD patients n = 147; controls n = 47). For all participants, we obtained color fundus photographs (for AMD staging) and fasting urine samples, which were analyzed using 1H nuclear magnetic resonance (NMR) spectroscopy. Our results revealed that in both cohorts, urinary metabolomic profiles differed mostly between controls and late AMD patients, but important differences were also found between controls and subjects with early AMD. Analysis of the metabolites responsible for these separations revealed that, even though distinct features were observed for each cohort, AMD was in general associated with depletion of excreted citrate and selected amino acids at some stage of the disease, suggesting enhanced energy requirements. In conclusion, NMR metabolomics enabled the identification of urinary signals of AMD and its severity stages, which might represent potential metabolomic biomarkers of the disease.

From the Cover: Metabolism Modulation in Different Organs by Silver Nanoparticles: An NMR Metabolomics Study of a Mouse Model

Although silver nanoparticles (AgNPs) are widely disseminated and show great potential in the biomedical field, there is a recognized need to better understand their action at the metabolic and functional levels. In this work, we have used NMR metabolomics, together with conventional clinical chemistry and histological examination, to characterize multi-organ and systemic metabolic responses to AgNPs intravenously administered to mice at 8 mg/kg body weight (a dose not eliciting overt toxicity). The major target organs of AgNPs accumulation, liver and spleen, showed the greatest metabolic changes, in a clear 2-stage response. In particular, the liver of dosed mice was found to switch from glycogenolysis and lipid storage, at 6 h postinjection, to glycogenesis and lipolysis, at subsequent times up to 48 h. Moreover, metabolites related to antioxidative defense, immunoregulation and detoxification seemed to play a crucial role in avoiding major hepatic damage. The spleen showed several early changes, including depletion of several amino acids, possibly reflecting impairment of hemoglobin recycling, while only a few differences remained at 48 h postinjection. In the heart, the metabolic shift towards TCA cycle intensification and increased ATP production possibly reflected a beneficial adaptation to the presence of AgNPs. On the other hand, the TCA cycle appeared to be down regulated in the lungs of injected mice, which showed signs of inflammation. Thekidneys showed the mildest metabolic response to AgNPs. Overall, this study has shown that NMR metabolomics is a powerful tool to monitor invivo metabolic responses to nanoparticles, revealing unforeseen effects.

Intestinal Microbial and Metabolic Profiling of Mice Fed with High-Glucose and High-Fructose Diets

Increased sugar intake is implicated in Type-2 diabetes and fatty liver disease; however, the mechanisms through which glucose and fructose promote these conditions are unclear. We hypothesize that alterations in intestinal metabolite and microbiota profiles specific to each monosaccharide are involved. Two groups of six adult C57BL/6 mice were fed for 10-weeks with diets with glucose (G) or fructose (F) as sole carbohydrates, and a third group was fed with a normal chow carbohydrate mixture (N). Fecal metabolites were profiled by nuclear magnetic resonance (NMR) and microbial composition by real-time polymerase chain reaction (qPCR). Although N, G and F mice exhibited similar weight gains (with slight slower gains for F) and glucose tolerance, multivariate analysis of NMR data indicated that F mice were separated from N and G, with decreased butyrate and glutamate and increased fructose, succinate, taurine, tyrosine, and xylose. The different sugar diets also resulted in distinct intestinal microbiota profiles. That associated with fructose seemed to hold more potential to induce host metabolic disturbances compared to glucose, mainly by promoting bile acid deconjugation and taurine release and compromising intestinal barrier integrity. This may reflect the noted nonquantitative intestinal fructose absorption hence increasing its availability for microbial metabolism, a subject for further investigation.

Human plasma metabolomics in age-related macular degeneration (AMD) using nuclear magnetic resonance spectroscopy

PURPOSE

To differentiate the plasma metabolomic profile of patients with age related macular degeneration (AMD) from that of controls, by Nuclear Magnetic Resonance (NMR) spectroscopy.

METHODS

Two cohorts (total of 396 subjects) representative of central Portugal and Boston, USA phenotypes were studied. For each cohort, subjects were grouped according to AMD stage (early, intermediate and late). Multivariate analysis of plasma NMR spectra was performed, followed by signal integration and univariate analysis.

RESULTS

Small changes were detected in the levels of some amino acids, organic acids, dimethyl sulfone and specific lipid moieties, thus providing some biochemical information on the disease. The possible confounding effects of gender, smoking history and age were assessed in each cohort and found to be minimal when compared to that of the disease. A similar observation was noted in relation to age-related comorbidities. Furthermore, partially distinct putative AMD metabolite fingerprints were noted for the two cohorts studied, reflecting the importance of nutritional and other lifestyle habits in determining AMD metabolic response and potential biomarker fingerprints. Notably, some of the metabolite changes detected were noted as potentially differentiating controls from patients diagnosed with early AMD.

CONCLUSION

For the first time, this study showed metabolite changes in the plasma of patients with AMD as compared to controls, using NMR. Geographical origins were seen to affect AMD patients´ metabolic profile and some metabolites were found to be valuable in potentially differentiating controls from early stage AMD patients. Metabolomics has the potential of identifying biomarkers for AMD, and further work in this area is warranted.

Quinones as Strecker degradation reagents in wine oxidation processes

The Strecker aldehydes formed during the reaction between α-amino acids (phenylalanine or methionine) and either gallic acid, caffeic acid or (+)-catechin ortho-quinones were evaluated in wine-model systems. It was demonstrated that phenylacetaldehyde was formed by quinone intermediates at wine pH. The highest amounts of phenylacetaldehyde during the 10days of experiment (69±5µg/L/day; 7x>Control) were obtained from (+) catechin, followed by gallic acid (61±4µg/L/day; 6x>Control) and caffeic acid (41±4µg/L/day; 4x>Control). The intermediate structures delivered from the reaction of ortho-quinones with α-amino acids were demonstrated by MSⁿ.

Characterization of 2,3-diarylxanthones by electrospray mass spectrometry: gas-phase chemistry versus known antioxidant activity properties

RATIONALE

Xanthones (XH) are a class of heterocyclic compounds widely distributed in nature that hold numerous noteworthy biological and antioxidant activities. Therefore, it is of utmost importance to achieve relevant detailed structural information to understand and assist prediction of their biological properties. The potential relationship between radical-mediated xanthone chemistry in the gas phase and their promising antioxidant activities has not been previously explored.

METHODS

Protonated xanthones XH1-9 were generated in the gas phase by electrospray ionization (ESI) and the main fragmentation pathways of the protonated XH1-9 formed due to collision-induced dissociation (CID) were investigated.

RESULTS

In the CID-MS/MS spectra of [M+H](+) ions of XH1, XH2 and XH4 the product ions formed due to H2 O elimination corresponding to the base peak of the spectra. For the remaining six xanthones (XH3, XH5-9), showing the most promising biological profile, the product ion produced with the highest relative abundance (RA) corresponded to the one formed through concomitant loss of H2 O plus CO. Indicative of an inexistent or lower biological activity is the combined loss of CO plus O unique to the CID-MS/MS spectra of XH1, XH2, XH4, and XH5. The product ion formed by loss of 64 Da (concomitant loss of two molecules of H2 O plus CO) is only observed for xanthones containing a catechol unit (XH3 and XH6-9). This product ion has the highest RA for the most potent scavenger of reactive oxygen and nitrogen species XH9 that contains two of these catechol moieties.

CONCLUSIONS

A strong relationship between some of the biological activities of the studied 2,3-diarylxanthones and their ESI-MS/MS fragmentation spectra was found. The multivariate statistical analysis results suggest that the selected MS features are related to the important biological features. Copyright © 2016 John Wiley & Sons, Ltd.

Prediction of Gestational Diabetes through NMR Metabolomics of Maternal Blood

Metabolic biomarkers of pre- and postdiagnosis gestational diabetes mellitus (GDM) were sought, using nuclear magnetic resonance (NMR) metabolomics of maternal plasma and corresponding lipid extracts. Metabolite differences between controls and disease were identified through multivariate analysis of variable selected (1)H NMR spectra. For postdiagnosis GDM, partial least squares regression identified metabolites with higher dependence on normal gestational age evolution. Variable selection of NMR spectra produced good classification models for both pre- and postdiagnostic GDM. Prediagnosis GDM was accompanied by cholesterol increase and minor increases in lipoproteins (plasma), fatty acids, and triglycerides (extracts). Small metabolite changes comprised variations in glucose (up regulated), amino acids, betaine, urea, creatine, and metabolites related to gut microflora. Most changes were enhanced upon GDM diagnosis, in addition to newly observed changes in low-Mw compounds. GDM prediction seems possible exploiting multivariate profile changes rather than a set of univariate changes. Postdiagnosis GDM is successfully classified using a 26-resonance plasma biomarker. Plasma and extracts display comparable classification performance, the former enabling direct and more rapid analysis. Results and putative biochemical hypotheses require further confirmation in larger cohorts of distinct ethnicities.

Changes in the metabolome of lettuce leaves due to exposure to mancozeb pesticide

This paper describes a proton high resolution magic angle spinning (HRMAS) nuclear magnetic resonance (NMR) metabolomic study of lettuce (Lactuca sativa L.) leaves to characterise metabolic adaptations during leaf growth and exposure to mancozeb. Metabolite variations were identified through multivariate analysis and checked through spectral integration. Lettuce growth was accompanied by activation of energetic metabolism, preferential glucose use and changes in amino acids, phospholipids, ascorbate, nucleotides and nicotinate/nicotinamide. Phenylalanine and polyphenolic variations suggested higher oxidative stress at later growth stages. Exposure to mancozeb induced changes in amino acids, fumarate and malate, suggesting Krebs cycle up-regulation. In tandem disturbances in sugar, phospholipid, nucleotide and nicotinate/nicotinamide metabolism were noted. Additional changes in phenylalanine, dehydroascorbate, tartrate and formate were consistent with a higher demand for anti-oxidant defence mechanisms. Overall, lettuce exposure to mancozeb was shown to have a significant impact on plant metabolism, with mature leaves tending to be more extensively affected than younger leaves.

Lifelong exercise training modulates cardiac mitochondrial phosphoproteome in rats

Moderate physical activity has traditionally been associated with the improvement of cardiac function and, consequently, with the extension of life span. Mitochondria play a key role in the adaptation of heart muscle to exercise-related metabolic demands. In order to disclose the molecular mechanisms underlying the beneficial effect of lifelong physical activity in cardiac function, we performed label-free quantitative mass spectrometry-based proteomics of Sprague-Dawley rat heart mitochondrial proteome and phosphoproteome. Our data revealed that 54 weeks of moderate treadmill exercise modulates the abundance of proteins involved in the generation of precursor metabolites and cellular respiration, suggesting an increase in carbohydrate oxidation-based metabolism. Moreover, from the 1335 phosphopeptides identified in this study, 6 phosphosites were exclusively assigned to heart mitochondria from sedentary rats and 17 to exercised animals, corresponding to 6 and 16 proteins, respectively. Most proteins exhibiting significant alterations in specific phosphorylation sites were involved in metabolism. Analysis of the acquired data led to the identification of several kinases potentially modulated by exercise training, which were selected for further validation. Indeed, higher protein abundance levels of RAF and p38 in mitochondria were confirmed to be modulated by sustained exercise. Our work describes the plasticity of heart mitochondria in response to long exercise programs manifested by the reprogramming of phosphoproteome and provides evidence for the kinases involved in the regulation of metabolic pathways and mitochondrial maintenance.