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Microvascular obstruction (MVO) portends a higher risk of remodelling and adverse events following ST-segment elevation myocardial infarction (STEMI). However, data regarding the implications of MVO in STEMI beyond five years of follow-up are scarce. This is a pooled analysis of three observational studies including 876 prospectively enrolled reperfused first STEMI patients, who underwent cardiac magnetic resonance imaging with late gadolinium enhancement (LGE), between 2003-2019. Median follow-up duration was 6.3 (IQR 3.6-9.3) years. The primary outcome was all-cause mortality. The secondary outcome was a combined endpoint of all-cause mortality and recurrent ischemic events (i.e., myocardial infarction or stroke). We performed Cox regression analyses with a time-dependent covariate. The study population consisted of 876 patients, mean age 59 years ± 12, 720 men (82%). MVO was present in 499 patients (58%). The presence of MVO was independently associated with all-cause mortality up to six years post-STEMI (Hazard Ratio [HR] 2.23, 95% CI 1.09-4.57, p = 0.029), but not after six years post-STEMI (HR 0.98, 95% CI 0.45-2.12, p = 0.958). Presence of MVO was not significantly associated with a combined endpoint of all-cause mortality and recurrent ischemic events before or after six years of follow-up (HR 1.27, 95% CI 0.81-1.99, p = 0.294 and HR 0.68, 95% CI 0.35-1.31, p = 0.244, respectively). In STEMI patients, the presence of MVO by cardiac magnetic resonance imaging is associated with a more than two-fold higher risk of all-cause mortality up to six years after the index event. This relation seems to dissipate beyond this time period.

Background In patients with bicuspid valve (BAV), ascending aorta (AAo) dilatation may be caused by altered flow patterns and wall shear stress (WSS). These differences may explain different aortic dilatation morphotypes. Using 4D-flow cardiovascular magnetic resonance (CMR), we aimed to analyze differences in flow patterns and regional axial and circumferential WSS maps between BAV phenotypes and their correlation with ascending aorta dilatation morphotype. Methods One hundred and one BAV patients (aortic diameter ≤ 45 mm, no severe valvular disease) and 20 healthy subjects were studied by 4D-flow CMR. Peak velocity, flow jet angle, flow displacement, in-plane rotational flow (IRF) and systolic flow reversal ratio (SFRR) were assessed at different levels of the AAo. Peak-systolic axial and circumferential regional WSS maps were also estimated. Unadjusted and multivariable adjusted linear regression analyses were used to identify independent correlates of aortic root or ascending dilatation. Age, sex, valve morphotype, body surface area, flow derived variables and WSS components were included in the multivariable models. Results The AAo was non-dilated in 24 BAV patients and dilated in 77 (root morphotype in 11 and ascending in 66). BAV phenotype was right-left (RL-) in 78 patients and right-non-coronary (RN-) in 23. Both BAV phenotypes presented different outflow jet direction and velocity profiles that matched the location of maximum systolic axial WSS. RL-BAV velocity profiles and maximum axial WSS were homogeneously distributed right-anteriorly, however, RN-BAV showed higher variable profiles with a main proximal-posterior distribution shifting anteriorly at mid-distal AAo. Compared to controls, BAV patients presented similar WSS magnitude at proximal, mid and distal AAo ( p  = 0.764, 0.516 and 0.053, respectively) but lower axial and higher circumferential WSS components ( p  < 0.001 for both, at all aortic levels). Among BAV patients, RN-BAV presented higher IRF at all levels ( p  = 0.024 proximal, 0.046 mid and 0.002 distal AAo) and higher circumferential WSS at mid and distal AAo ( p  = 0.038 and 0.046, respectively) than RL-BAV. However, axial WSS was higher in RL-BAV compared to RN-BAV at proximal and mid AAo ( p  = 0.046, 0.019, respectively). Displacement and axial WSS were independently associated with the root-morphotype, and circumferential WSS and SFRR with the ascending-morphotype. Conclusions Different BAV-phenotypes present different flow patterns with an anterior distribution in RL-BAV, whereas, RN-BAV patients present a predominant posterior outflow jet at the sinotubular junction that shifts to anterior or right anterior in mid and distal AAo. Thus, RL-BAV patients present a higher axial WSS at the aortic root while RN-BAV present a higher circumferential WSS in mid and distal AAo. These results may explain different AAo dilatation morphotypes in the BAV population.

Sulphate-reducing bacteria are important players in the global sulphur and carbon cycles, with considerable economical and ecological impact. However, the process of sulphate respiration is still incompletely understood. Several mechanisms of energy conservation have been proposed, but it is unclear how the different strategies contribute to the overall process. In order to obtain a deeper insight into the energy metabolism of sulphate-reducers whole-genome microarrays were used to compare the transcriptional response of Desulfovibrio vulgaris Hildenborough grown with hydrogen/sulphate, pyruvate/sulphate, pyruvate with limiting sulphate, and lactate/thiosulphate, relative to growth in lactate/sulphate. Growth with hydrogen/sulphate showed the largest number of differentially expressed genes and the largest changes in transcript levels. In this condition the most up-regulated energy metabolism genes were those coding for the periplasmic [NiFeSe] hydrogenase, followed by the Ech hydrogenase. The results also provide evidence for the involvement of formate cycling and the recently proposed ethanol pathway during growth in hydrogen. The pathway involving CO cycling is relevant during growth on lactate and pyruvate, but not during growth in hydrogen as the most down-regulated genes were those coding for the CO-induced hydrogenase. Growth on lactate/thiosulphate reveals a down-regulation of several energy metabolism genes similar to what was observed in the presence of nitrite. This study identifies the role of several proteins involved in the energy metabolism of D. vulgaris and highlights several novel genes related to this process, revealing a more complex bioenergetic metabolism than previously considered.

Objectives Manual assessment of aortic diameters on double-oblique reformatted computed tomography angiograms (CTA) is considered the current standard, although the reproducibility for growth rates has not been reported. Deformable registration of CTA has been proposed to provide 3D aortic diameters and growth maps, but validation is lacking. This study aimed to quantify accuracy and inter-observer reproducibility of registration-based and manual assessment of aortic diameters and growth rates. Methods Forty patients with ≥ 2 CTA acquired at least 6 months apart were included. Aortic diameters and growth rate were obtained in the aortic root and the entire thoracic aorta using deformable image registration by two independent observers, and compared with the current standard at typical anatomical landmarks. Results Compared with manual assessment, the registration-based technique presented low bias (0.46 mm), excellent agreement (ICC = 0.99), and similar inter-observer reproducibility (ICC = 0.99 for both) for aortic diameters; and low bias (0.10 mm/year), good agreement (ICC = 0.82), and much higher inter-observer reproducibility for growth rates (root: ICC = 0.96 vs 0.68; thoracic aorta: ICC = 0.96 vs 0.80). Registration-based growth rate reproducibility over a 6-month-long follow-up was similar to that obtained by manual assessment after 2.7 years (LoA = [− 0.01, 0.33] vs [− 0.13, 0.21] mm/year, respectively). Mapping of diameter and growth rate was highly reproducible (ICC > 0.9) in the whole thoracic aorta. Conclusions Registration-based assessment of aortic dilation on CTA is accurate and substantially more reproducible than the current standard, even at follow-up as short as 6 months, and provides robust 3D mapping of aortic diameters and growth rates beyond the pre-established anatomic landmarks. Key Points • Registration-based semi-automatic assessment of progressive aortic dilation on CTA is accurate and substantially more reproducible than the current standard. • The registration-based technique allows robust growth rate assessment at follow-up as short as 6 months, with a similar reproducibility to that obtained by manual assessment at around 3 years. • The use of image registration provides robust 3D mapping of aortic diameters and growth rates beyond the pre-established anatomic landmarks.

Patency of the false lumen in chronic aortic dissection (AD) is associated with aortic dilation and long-term aortic events. However, predictors of adverse outcomes in this population are limited. The aim of this study was to evaluate the relationship between aortic growth rate and false lumen flow dynamics and biomechanics in patients with chronic, patent AD. Patients with a chronic AD with patent false lumen in the descending aorta and no genetic connective tissue disorder underwent an imaging follow-up including a contrast-enhanced 4D flow cardiovascular magnetic resonance (CMR) protocol and two consecutive computed tomography angiograms (CTA) acquired at least 1 year apart. A comprehensive analysis of anatomical features (including thrombus quantification), and false lumen flow dynamics and biomechanics (pulse wave velocity) was performed. Fifty-four consecutive patients with a chronic, patent false lumen in the descending aorta were included (35 surgically-treated type A AD with residual tear and 19 medically-treated type B AD). Median follow-up was 40 months. The in-plane rotational flow, pulse wave velocity and the percentage of thrombus in the false lumen were positively related to aortic growth rate (p = 0.006, 0.017, and 0.037, respectively), whereas wall shear stress showed a trend for a positive association (p = 0.060). These results were found irrespectively of the type of AD. In patients with chronic AD and patent false lumen of the descending aorta, rotational flow, pulse wave velocity and wall shear stress are positively related to aortic growth rate, and should be implemented in the follow-up algorithm of these patients. Further prospective studies are needed to confirm if the assessment of these parameters helps to identify patients at higher risk of adverse clinical events.

Introduction: Heart failure (HF) is a clinical syndrome caused by structural and functional cardiac abnormalities resulting in the impairment of cardiac function, entailing significant mortality. The prevalence of HF has reached epidemic proportions in the last few decades, mainly in the elderly, but recent evidence suggests that its epidemiology may be changing. Objective: Our objective was to estimate the prevalence of HF and its subtypes, and to characterize HF in a population of integrated care users. Material and Methods: A non-interventional cross-sectional study was performed in a healthcare center that provides primary, secondary and tertiary health cares. Echocardiographic parameters (left ventricle ejection fraction (LVEF) and evidence of structural heart disease) and elevated levels of natriuretic peptides were used to define two HF phenotypes: (i) HF with a reduced ejection fraction (HFrEF, LVEF ≤ 40% and either NT-proBNP ≥ 400 pg/mL (≥600 pg/mL if atrial fibrillation (AF)/flutter) or BNP ≥ 100 pg/mL (≥125 pg/mL if AF/flutter)) and (ii) HF with a non-reduced ejection fraction (HFnrEF), which encompasses both HFpEF (LVEF ≥ 50% and either NT-proBNP ≥ 200 pg/mL (≥600 pg/mL if AF/flutter) or BNP ≥ 100 pg/mL (≥125 pg/mL if AF/flutter) in the presence of at least one structural cardiac abnormality) and HF with a mildly reduced fraction (HFmrEF, LVEF within 40–50% and either NT-proBNP ≥ 200 pg/mL (≥600 pg/mL if AF/flutter) or BNP ≥ 100 pg/mL (≥125 pg/mL if AF/flutter) in the presence of at least one structural cardiac abnormality). The significance threshold was set at p ≤ 0.001. Results: We analyzed 126,636 patients with a mean age of 52.2 (SD = 18.3) years, with 57% (n = 72,290) being female. The prevalence of HF was 2.1% (n = 2700). The HF patients’ mean age was 74.0 (SD = 12.1) years, and 51.6% (n = 1394) were female. Regarding HF subtypes, HFpEF accounted for 65.4% (n = 1765); 16.1% (n = 434) had HFmrEF and 16.3% (n = 439) had HFrEF. The patients with HFrEF were younger (p < 0.001) and had a history of myocardial infarction more frequently (p < 0.001) compared to HFnrEF, with no other significant differences between the HF groups. The HFrEF patients were more frequently prescribed CV medications than HFnrEF patients. Type 2 Diabetes Mellitus (T2D) was present in 44.7% (n = 1207) of the HF patients. CKD was more frequently present in T2D vs. non-T2D HF patients at every stage (p < 0.001), as well as stroke, peripheral artery disease, and microvascular disease (p < 0.001). Conclusions: In this cohort, considering a contemporary definition, the prevalence of HF was 2.1%. HFrEF accounted for 16.3% of the cases, with a similar clinical–epidemiological profile having been previously reported in the literature. Our study revealed a high prevalence of patients with HFpEF (65.4%), raising awareness for the increasing prevalence of this entity in cardiology practice. These results may guide local and national health policies and strategies for HF diagnosis and management.

Objective Bicuspid aortic valve (BAV), the most common congenital valve defect, is associated with increased risk of aortic dilation and related complications; however, current risk assessment is not effective. Most of BAV have three leaflets with a fusion between two of them of variable length. This study aimed to ascertain whether the extent of leaflet fusion (often called raphe) is related to aortic dilation and flow abnormalities in BAV with no significant valvular dysfunction. Methods One hundred and twenty BAV patients with no significant valvular dysfunction or history of surgical repair or aortic valve replacement were consecutively and prospectively enrolled (September 2014–October 2018). Cardiac magnetic resonance protocol included a 4D flow sequence for haemodynamic assessment. Moreover, a stack of double-oblique cine images of the aortic valve were used to quantify fusion length (in systole) and leaflet length (diastole). Inter- and intra-observer reproducibility was tested in 30 randomly selected patients. Results Aortic valve leaflet fusion was measurable in 112 of 120 (93%) cases with good reproducibility (ICC = 0.826). Fusion length varied greatly (range: 2.3–15.4 mm; mean: 7.8 ± 3.2 mm). After correction for demographic and clinical conditions, fusion length was independently associated with diameter and z -score at the sinus of Valsalva ( p  = 0.002 and p  = 0.002, respectively) and ascending aorta ( p  = 0.028 and p  = 0.046). Fusion length was positively related to flow asymmetry, vortices and circumferential wall shear stress, thereby possibly providing a pathophysiological link with aortic dilation. Conclusions Aortic valve fusion length is related to aortic dilation and flow abnormalities in BAV patients. Key Points • The length of the fusion between leaflets in non-dysfunctional bicuspid aortic valves varies substantially and can be reliably measured by cine CMR. • Aortic valve leaflet fusion length is independently related to aortic sinus and ascending aorta diameter. • Increased flow asymmetry, circumferential wall shear stress and presence of vortices are positively related to aortic valve leaflet fusion length.

Traditional volumetric parameters fall short of capturing the complex, phasic nature of atrial function. In contrast, atrial strain has become recognized as a sensitive, non-invasive imaging marker that enables earlier detection of myocardial dysfunction, refined risk stratification, and individualized therapeutic decision-making across a wide range of cardiovascular diseases. Cardiovascular magnetic resonance feature tracking (CMR-FT) has emerged as a robust imaging technique for evaluating atrial strain, offering high spatial resolution, high reproducibility, and independence from acoustic window limitations. Despite its promise, the routine clinical adoption of CMR-FT atrial strain remains limited. Key barriers include intervendor variability in strain values, the absence of standardized post-processing protocols, the lengthy acquisition times inherent to CMR studies, and the time required for post-processing atrial strain analysis. Overcoming these barriers is crucial to facilitate the integration of atrial strain assessment into routine clinical CMR protocols, particularly in patients with heart failure, valvular disease, or cardiomyopathy who undergo imaging for diagnostic or prognostic evaluation.

The gram-negative anaerobic gut bacterium Bilophila wadsworthia is the third most common isolate in perforated and gangrenous appendicitis, being also found in a variety of other infections. This organism performs a unique kind of anaerobic respiration in which taurine, a major organic solute in mammals, is used as a source of sulphite that serves as terminal acceptor for the electron transport chain. We show here that molecular hydrogen, one of the major products of fermentative bacteria in the colon, is an excellent growth substrate for B. wadsworthia. We have quantified the enzymatic activities associated with the oxidation of H₂, formate and pyruvate for cells obtained in different growth conditions. The cell extracts present high levels of hydrogenase activity, and up to five different hydrogenases can be expressed by this organism. One of the hydrogenases appears to be constitutive, whereas the others show differential expression in different growth conditions. Two of the hydrogenases are soluble and are recognised by antibodies against a [FeFe] hydrogenase of a sulphate reducing bacterium. One of these hydrogenases is specifically induced during fermentative growth on pyruvate. Another two hydrogenases are membrane-bound and show increased expression in cells grown with hydrogen. Further work should be carried out to reveal whether oxidation of hydrogen contributes to the virulence of B. wadsworthia.

Succinate is enhanced during initial reperfusion in blood from the coronary sinus in ST-segment elevation myocardial infarction (STEMI) patients and in pigs submitted to transient coronary occlusion. Succinate levels might have a prognostic value, as they may correlate with edema volume or myocardial infarct size. However, blood from the coronary sinus is not routinely obtained in the CathLab. As succinate might be also increased in peripheral blood, we aimed to investigate whether peripheral plasma concentrations of succinate and other metabolites obtained during coronary revascularization correlate with edema volume or infarct size in STEMI patients. Plasma samples were obtained from peripheral blood within the first 10 min of revascularization in 102 STEMI patients included in the COMBAT-MI trial (initial TIMI 1) and from 9 additional patients with restituted coronary blood flow (TIMI 2). Metabolite concentrations were analyzed by 1 H-NMR. Succinate concentration averaged 0.069 ± 0.0073 mmol/L in patients with TIMI flow ≤ 1 and was significantly increased in those with TIMI 2 at admission (0.141 ± 0.058 mmol/L, p  < 0.05). However, regression analysis did not detect any significant correlation between most metabolite concentrations and infarct size, extent of edema or other cardiac magnetic resonance (CMR) variables. In conclusion, spontaneous reperfusion in TIMI 2 patients associates with enhanced succinate levels in peripheral blood, suggesting that succinate release increases overtime following reperfusion. However, early plasma levels of succinate and other metabolites obtained from peripheral blood does not correlate with the degree of irreversible injury or area at risk in STEMI patients, and cannot be considered as predictors of CMR variables. Trial registration: Registered at www.clinicaltrials.gov (NCT02404376) on 31/03/2015. EudraCT number: 2015-001000-58.