Coronary microvascular dysfunction correlates with the new onset of cardiac allograft vasculopathy in heart transplant patients with normal coronary angiography.

Coronary microvascular dysfunction is emerging as a strong predictor of outcome in heart transplantation (HT). We assessed the validity of microvascular dysfunction, defined by means of a reduced coronary flow reserve (CFR), as a factor associated with new onset epicardial cardiac allograft vasculopathy (CAV) or death. We studied 105 patients at 4 ± 1 years post-HT with a normal coronary angiography (CA). New onset CAV was assessed by CA. CFR was assessed in the left anterior descending (LAD) coronary artery by transthoracic Doppler echocardiography and calculated as the ratio of hyperaemic to basal blood flow velocity. A CFR ≤ 2.5 was considered abnormal. Epicardial CAV onset or death was assessed during a follow-up of 10 years. New onset CAV was diagnosed in 30 patients (28.6%) (Group A), and the CA was normal in the remaining 75 patients (71.4%) (Group B). Group A had reduced CFR compared with group B (2.4 ± 0.6 vs. 3.2 ± 0.7, p < 0.0001). A CFR ≤ 2.5 was independently associated with a higher probability of new onset CAV (p < 0.0001) and a higher probability of death, regardless of CAV onset (p < 0.01). Microvascular dysfunction is independently associated with the onset of epicardial CAV, and associated with a higher risk of death, regardless of CAV onset.

Inflammatory cell burden and phenotype in endomyocardial biopsies with antibody-mediated rejection (AMR): a multicenter pilot study from the AECVP.

This multicenter case-controlled pilot study evaluated myocardial inflammatory burden (IB) and phenotype in endomyocardial biopsies (EMBs) with and without pathologic antibody-mediated rejection (pAMR). Sixty-five EMBs from five European heart transplant centers were centrally reviewed as positive (grade 2, n = 28), suspicious (grade 1, n = 7) or negative (n = 30) for pAMR. Absolute counts of total, intravascular (IV) and extravascular (EV) immunophenotyped mononuclear cells were correlated with pAMR grade, capillary C4d deposition, donor specific antibody (DSA) status and acute cellular rejection (ACR). In pAMR+ biopsies, equivalent number of IV CD3+ T lymphocytes (23 ± 4/0.225 mm(2) ) and CD68+ macrophages (21 ± 4/0.225 mm(2) ) were seen. IB and cell phenotype correlated with pAMR grade, C4d positivity and DSA positivity (p < 0.0001). High numbers of IV T lymphocytes were associated with low grade ACR (p = 0.002). In late-occurring AMR EV plasma cells occurring in 34% of pAMR+ EMBs were associated with higher IB. The IB in AMR correlated with pAMR+, C4d positivity and DSA positivity. In pAMR+ equivalent numbers of IV T lymphocytes and macrophages were found. The presence of plasma cells was associated with a higher IB and occurrence of pAMR late after transplantation.

Intraplaque hemorrhage in cardiac allograft vasculopathy.

Plaque hemorrhage, inflammation and microvessel density are key determinants of plaque vulnerability in native coronary atherosclerosis (ATS). This study investigates the role of intraplaque hemorrhage (IPH) and its relation with inflammation and microvessels in cardiac allograft vasculopathy (CAV) in posttransplanted patients. Seventy coronary plaques were obtained from 12 patients who died because of CAV. For each patient we collected both native heart and the allograft, at the time of transplantation and autopsy, respectively. Intralesion inflammation, microvessels and IPH were assessed semi-quantitatively. IPH was observed in 21/35 (60%) CAV lesions and in 8/35 (22.9%) native ATS plaques, with a strong association between fibrocellular lesions and IPH (p = 0.0142). Microvessels were detected in 26/35 (74.3%) of CAV lesions with perivascular leakage as sign of endothelial damage in 18/26 (69.2%). IPH was strongly associated with microvessels (p < 0.0001). Inflammation was present in 31/35 (88.6%) of CAV lesions. CAV IPH+ lesions were characterized by presence of both fresh and old hemorrhage in 12/21 (57.1%). IPH, associated with microvessel damage and inflammation, is an important feature of CAV. Fresh and old intralesion hemorrhage suggests ongoing remodeling processes promoting the lesion progression and vulnerability.

HLA-DRB1 typing by micro-bead array assay identifies the origin of early lymphoproliferative disorder in a heart transplant recipient.

We report the case of a 68-year-old woman who underwent heart transplantation for hypertrophic cardiomyopathy. Two months after the transplant she developed mild fever and dyspnea with a marked drop in left ventricle ejection fraction of 31%. Coronary angiography was negative for cardiac allograft vasculopathy. Endomyocardial biopsy revealed ischemic damage with no evidence of acute cellular rejection, antibody-mediated rejection or viral myocarditis. A neoplastic process was suspected even though full-body computerized tomography was negative for malignancy. The patient died 4 months after transplantation. The autopsy showed acute antero-septal myocardial infarction due to a nodular epicardial EBV-related posttransplant lymphoproliferative disorder (PTLD) infiltrating the left anterior descending coronary artery with occlusive neoplastic thrombosis. We highlight two major aspects of this case: (1) the unusual occurrence of early PTLD involving the cardiac allograft and causing a fatal outcome, (2) the application of an immunological technique for HLA-DRB1 typing to posttransplant paraffin-embedded autopsy material to identify the recipient origin of this early malignancy, thus excluding a possible donor-transmitted neoplasm.

Wet-priming extracorporeal membrane oxygenation device maintains sterility for up to 35 days of follow-up.

In emergency cases, rapid extracorporeal membrane oxygenation (ECMO) device initialization is able to drastically reduce the incidence of patient morbidity and/or mortality. Pre-assembled and ready-to-use ECMO circuits might save up to 30-60 critical minutes in patient management. Six ECMO circuits (Oxygenator D905 EOS with REVOLUTION™ pump and Sorin PTS) were assembled in the operating room in standard conditions and then placed at 37°C for 35 days in order to evaluate possible contamination and ingrowth of micro-organisms. Every 7 days after ECMO circuit assembly and wet-priming, samples of priming fluid were analyzed to verify the presence/absence of possible common contaminants (Enterobacteriaceae, Staphylococcus aureus and fungi). Moreover, two supplementary circuits, used as positive controls, were deliberately inoculated with a known concentration of a Escherichia coli strain and prime samplings carried out at different time-points to determine bacterial growth rate. Sterility was maintained in the ECMO circuits for up to 35 days.

Malpratice claims in cardiology and cardiac surgery: A medico-legal issue.

Medical liability has become a challenge in every physician's modern practice with the consequent loss of the physician's autonomy and an increase in "defensive medicine". From this perspective, the role of Legal Medicine in assessing medical liability has become increasingly specific and a homogenization of the methods of ascertainment is increasingly necessary, since such a process can contribute to strengthening the guarantees in professional liability procedures. Focusing on malpractice claims in the field of cardiology, the complexity of the management of cardiac pathologies and the frequency of severe adverse events implies the importance of a multi-disciplinary approach, together with the application of a shared ascertainment methodology. In particular, it is essential for the forensic pathologist to collaborate with experts in cardio-pathology, cardiology and/or cardiac surgery in cases of alleged medical liability in the cardiologic field and to follow the guidelines which have been produced to assist the expert dealing with deaths reflecting cardiac disease, in order to prevent criticism of case analysis in medico-legal environments and to promote the standardization of the structure of the juridical-legislative medical malpractice lawsuits.

Left ventricular assist device and transcatheter edge-to-edge mitral valve repair in advanced heart failure: allies or enemies?

The implantation of left ventricular assist devices (LVADs) has been increasing, with good long-term results, in parallel with a growing population with advanced heart failure (HF). However, in some European countries, LVADs are still underused, with one of the main issues being the patient's late referral. On the contrary, the use of transcatheter edge-to-edge mitral valve repair (TEER) has exponentially increased over the past decade, expanding its potential use even in patients on the heart transplantation waiting list. Even though the study populations of the main trials that investigated the prognostic impact of LVAD and TEER are different, in clinical practice a clear distinction might not be so clear. Therefore, patients with refractory HF symptoms and significant mitral regurgitation should be thoroughly evaluated through a multidisciplinary Heart Team meeting with both an advanced HF specialist and interventional cardiologist, to avoid futile procedures and to define the optimal timing for advanced HF therapies, when they are indicated. We analyzed the main available studies and registries on both TEERs and LVADs and we compared their populations and outcomes, to provide the current evidence on the use of LVAD and TEER in the HF population, especially in the light of the recently released 5-year follow-up results, giving some insights on the Italian situation, and finally to stress the importance of a solid HF network between hospitals, aiming for advanced HF patients' timely referral for LVAD or heart transplants.

Errors in ozone risk assessment using standard conditions for converting ozone concentrations obtained by passive samplers in mountain regions.

Passive samplers are often employed to measure ozone concentrations in remote areas such as mountain forests. The potential ozone risk for vegetation is then assessed by calculating the AOT40 exposure index (accumulated hourly ozone concentration exceedances above 40 ppb, i.e. AOT40 = Σ([O(3)] - 40)Δt for any hourly ozone concentration [O(3)] > 40 ppb). AOT40 is customary calculated on the basis of ozone concentrations expressed as a volumetric mixing ratio, while lab sheets normally report ozone concentrations from passive samplers in mass units per cubic metre. Concentrations are usually converted from mass units to ppb using a standard conversion factor taking SATP (Standard Ambient Temperature and Pressure) conditions into account. These conditions, however, can vary considerably with elevation. As a consequence, the blanket application of a standard conversion factor may lead to substantial errors in reporting and mapping ozone concentrations and therefore in assessing potential ozone risk in mountain regions. In this paper we carry out a sensitivity analysis of the effects of uncertainties in estimations of air temperature (T) and atmospheric pressure (P) on the concentration conversion factor, and present two examples from two monitoring and mapping exercises carried out in the Italian Alps. We derived P and T at each site from adiabatic lapse rates for temperature and pressure and analysed the magnitude of error in concentration estimations. Results show that the concentration conversion is much more sensitive to uncertainties in P gradient estimation than to air temperature errors. The concentration conversion factor (cf) deviates 5% from the standard transformation at an elevation of 500 m asl. As a consequence, the standard estimated AOT40 at this elevation is about 13% less than the actual value. AOT40 was found to be underestimated by an average between 25% and 34% at typical elevations of mountain forest stands in the Italian Alps when a correct conversion factor for transforming ozone concentrations from µg m(-3) to ppb is not applied.

Transapical beating heart mitral valve repair versus conventional surgery: a propensity-matched study.

OBJECTIVES: Transapical Neochordae implantation (NC) allows beating heart mitral valve repair in patients with degenerative mitral regurgitation. The aim of this single-centre, retrospective study was to compare outcomes of NC versus conventional surgical (CS) mitral valve repair. METHODS: Data of patients who underwent isolated mitral valve repair with NC or CS from January 2010 to December 2018 were collected. A propensity score matching analysis was performed to reduce confounding due to baseline differences between groups. The primary end point was overall all-cause mortality; secondary end points were freedom from reoperation, freedom from moderate (2+) and from severe (3+) mitral regurgitation (MR) and New York Heart Association functional class in the overall population and in patients with isolated P2 prolapse (type A anatomy). RESULTS: Propensity analysis selected 88 matched pairs. There was no 30-day mortality in the 2 groups. Kaplan-Meier analysis showed similar 5-year survival in the 2 groups. Patients undergoing NC showed worse freedom from moderate MR (≥2+) (57.6% vs 84.6%; P < 0.001) and from severe MR (3+) at 5-year follow-up: 78.1% vs 89.7% (P = 0.032). In patients with type A anatomy, freedom from moderate MR and from severe MR was similar between groups (moderate: 63.9% vs 74.6%; P = 0.21; severe: 79.3% vs 79%; P = 0.77 in NC and FS, respectively). Freedom from reoperation was lower in the NC group: 78.9% vs 92% (P = 0.022) but, in type A patients, it was similar: 79.7% and 85% (P = 0.75) in the NC and CS group, respectively. More than 90% of patients of both groups were in New York Heart Association class I and II at follow-up. CONCLUSIONS: Transapical beating-heart mitral chordae implantation can be considered as an alternative treatment to CS, especially in patients with isolated P2 prolapse.

Excimer laser technology in percutaneous coronary interventions: Cardiovascular laser society's position paper.

Excimer Laser Coronary Atherectomy (ELCA) is a well-established therapy that emerged for the treatment of peripheral vascular atherosclerosis in the late 1980s, at a time when catheters and materials were rudimentary and associated with the most serious complications. Refinements in catheter technology and the introduction of improved laser techniques have led to their effective use for the treatment of a wide spectrum of complex coronary lesions, such as thrombotic lesions, severe calcific lesions, non-crossable or non-expandable lesions, chronic occlusions, and stent under-expansion. The gradual introduction of high-energy strategies combined with the contrast infusion technique has enabled us to treat an increasing number of complex cases with a low rate of periprocedural complications. Currently, the use of the ELCA has also been demonstrated to be effective in acute coronary syndrome (ACS), especially in the context of large thrombotic lesions.

Coronary flow reserve by transthoracic echocardiography predicts epicardial intimal thickening in cardiac allograft vasculopathy.

Cardiac allograft vasculopathy (CAV) is the leading cause of morbidity and mortality in heart transplantation (HT). We sought to investigate the role of coronary flow reserve (CFR) by contrast-enhanced transthoracic echocardiography (CE-TTE) in CAV diagnosis. CAV was defined as maximal intimal thickness (MIT) assessed by intravascular ultrasound (IVUS) > or =0.5 mm. CFR was assessed in the left anterior descending coronary artery in 22 HT recipients at 6 +/- 4 years post-HT. CAV was diagnosed in 10 patients (group A), 12 had normal coronaries (group B). The mean MIT was 0.7 +/- 0.1 mm (range 0.03-1.8). MIT was higher in group A (1.16 +/- 0.3 mm vs. 0.34 +/- 0.07 mm, p < 0.0001). CFR was 3.1 +/- 0.8 in all patients and lower in group A (2.5 +/- 0.6 vs. 3.7 +/- 0.3, p < 0.0001). CFR was inversely related with MIT (r =-0.774, p < 0.0001). A cut point of < or =2.9, identified as optimal by receiver operating characteristics analysis was 100% specific and 80% sensitive (PPV = 100%, NPV = 89%, Accuracy = 91%). CFR assessment by CE-TTE is a novel noninvasive diagnostic tool in the detection of CAV defined as MIT > or =0.5 mm. CFR by CE-TTE may reduce the need for routine IVUS in HT.

Early events in Populus hybrid and Fagus sylvatica leaves exposed to ozone.

This paper aims to investigate early responses to ozone in leaves of Fagus sylvatica (beech) and Populus maximowiczii x Populus berolinensis (poplar). The experimental setup consisted of four open-air (OA) plots, four charcoal-filtered (CF) open-top chambers (OTCs), and four nonfiltered (NF) OTCs. Qualitative and quantitative analyses were carried out on nonsymptomatic (CF) and symptomatic (NF and OA) leaves of both species. Qualitative analyses were performed applying microscopic techniques: Evans blue staining for detection of cell viability, CeCl3 staining of transmission electron microscope (TEM) samples to detect the accumulation of H2O2, and multispectral fluorescence microimaging and microspectrofluorometry to investigate the accumulation of fluorescent phenolic compounds in the walls of the damaged cells. Quantitative analyses consisted of the analysis of the chlorophyll a fluorescence transients (fast kinetics). The early responses to ozone were demonstrated by the Evans blue and CeCl3 staining techniques that provided evidence of plant responses in both species 1 month before foliar symptoms became visible. The fluorescence transients analysis, too, demonstrated the breakdown of the oxygen evolving system and the inactivation of the end receptors of electrons at a very early stage, both in poplar and in beech. The accumulation of phenolic compounds in the cell walls, on the other hand, was a species-specific response detected in poplar, but not in beech. Evans blue and CeCl3 staining, as well as the multispectral fluorescence microimaging and microspectrofluorometry, can be used to support the field diagnosis of ozone injury, whereas the fast kinetics of chlorophyll fluorescence provides evidence of early physiological responses.

Visible leaf injury in young trees of Fagus sylvatica L. and Quercus robur L. in relation to ozone uptake and ozone exposure. An Open-Top Chambers experiment in South Alpine environmental conditions.

An Open-Top Chambers experiment on Fagus sylvatica and Quercus robur seedlings was conducted in order to compare the performance of an exposure-based (AOT40) and a flux-based approaches in predicting the appearance of ozone visible injuries on leaves. Three different ozone treatments (charcoal-filtered; non-filtered; and open plots) and two soil moisture treatments (watered and non-watered plots) were performed. A Jarvisian stomatal conductance model was drawn up and parameterised for both species and typical South Alpine environmental conditions, thus allowing the calculation of ozone stomatal fluxes for every treatment. A critical ozone flux level for the onset of leaf visible injury in beech was clearly identified between 32.6 and 33.6 mmolO3 m(-2). In contrast, it was not possible to identify an exposure critical level using the AOT40 index. Water stress delayed the onset of the leaf visible injuries, but the flux-based approach was able to take it into account accurately.

Robustness of modelled ozone exposures and doses.

This study evaluates the robustness of the AOTX and AF(st)Y indices for assessing the ozone-induced risk to vegetation. These indices represent the accumulated concentration and stomatal flux, respectively, above a threshold value. The robustness is expressed as the sensitivity to changes in inputs and the uncertainty due to input errors. The input data are taken from a regional-scale chemical transport model. Both indices show increasing sensitivity with increasing threshold values. The sensitivity depends on the threshold and the characteristics of the frequency distribution for concentrations and stomatal fluxes. AF(st)Y appears less sensitive than AOTX for the thresholds adopted for critical levels. The couplings between concentration gradients and deposition algorithms complicate the assessment of the total uncertainty. For AF(st)Y, the uncertainty due to the modelled stomatal conductance may sometimes increase, but sometimes decrease, the overall uncertainty significantly. In particular, the maximum stomatal conductance plays an important role in determining the uncertainty.

Measuring, modelling and testing ozone exposure, flux and effects on vegetation in southern European conditions--what does not work? A review from Italy.

Ozone (O3) exposure at Italian background sites exceeds UN/ECE concentration-based critical levels (CLe(c)), if expressed in terms of AOT40. Yet the occurrence of adverse effects of O3 on forests and crops is controversial. Possible reasons include (i) ability of response indicators to provide an unbiased estimate of O3 effects, (ii) setting of current CLe(c) in terms of cut-off value and accumulation level, (iii) response functions adopted to infer a critical level, (iv) environmental limitation to O3 uptake and (v) inherent characteristics of Mediterranean vegetation. In particular, the two latter points suggest that critical levels based on accumulated stomatal flux (CLe(f)) can be a better predictor of O3 risk than CLe(c). While this concept is largely acknowledged, a number of factors may limit its applicability for routine monitoring. This paper reviews levels, uptake and vegetation response to O3 in Italy over recent years to discuss value, uncertainty and feasibility of different approaches to risk assessment.

Early and late adjustments of the photosynthetic traits and stomatal density in Quercus ilex L. grown in an ozone-enriched environment.

Quercus ilex L. seedlings were exposed in open-top chambers for one growing season to three levels of ozone (O3 ): charcoal filtered air, non-filtered air supplemented with +30% or +74% ambient air O3 . Key functional parameters related to photosynthetic performance and stomatal density were measured to evaluate the response mechanisms of Q. ilex to chronic O3 exposure, clarifying how ecophysiological traits are modulated during the season in an ozone-enriched environment. Dark respiration showed an early response to O3 exposure, increasing approximately 45% relative to charcoal-filtered air in both O3 enriched treatments. However, at the end of the growing season, maximum rate of assimilation (Amax ) and stomatal conductance (gs ) showed a decline (-13% and -36%, for Amax and gs , respectively) only in plants under higher O3 levels. Photosystem I functionality supported the capacity of Q. ilex to cope with oxidative stress by adjusting the energy flow partitioning inside the photosystems. The response to O3 was also characterised by increased stomatal density in both O3 enriched treatments relative to controls. Our results suggest that in order to improve the reliability of metrics for O3 risk assessment, the seasonal changes in the response of gs and photosynthetic machinery to O3 stress should be considered.

Guided tissue regeneration in heart valve replacement: from preclinical research to first-in-human trials.

Heart valve tissue-guided regeneration aims to offer a functional and viable alternative to current prosthetic replacements. Not requiring previous cell seeding and conditioning in bioreactors, such exceptional tissue engineering approach is a very fascinating translational regenerative strategy. After in vivo implantation, decellularized heart valve scaffolds drive their same repopulation by recipient's cells for a prospective autologous-like tissue reconstruction, remodeling, and adaptation to the somatic growth of the patient. With such a viability, tissue-guided regenerated conduits can be delivered as off-the-shelf biodevices and possess all the potentialities for a long-lasting resolution of the dramatic inconvenience of heart valve diseases, both in children and in the elderly. A review on preclinical and clinical investigations of this therapeutic concept is provided with evaluation of the issues still to be well deliberated for an effective and safe in-human application.

Post-transplant Lymphoproliferative Disorders: A Rare Case of Primary Pericardial Involvement Epstein-Barr Virus-Correlated in Heart Transplantation.

Post-transplant lymphoproliferative disorders (PTLDs) are considered a fatal consequence of immunosuppression. We report a case of a 52-year-old patient, who underwent a cardiac transplantation and presented undefined recurrent episodes of pleuropericardial effusions without lymphoadenomegaly at chest radiographs and computed tomography. Histopathological analysis of the bioptic pericardium showed a specific chronic inflammation. Monitoring endomyocardial biopsies (EMBs) showed only 1 episodes of greater than grade 2R acute cellular rejection requiring immunosuppressive treatment, mild vasculitis in 2 subsequently EMBs while constantly negative for antibody-mediated rejection or infection. Only a post-mortem examination demonstrated the presence of an aggressive acute non-Epstein-Barr virus (EBV)-related proliferative disorder with unusual primitive localization into the pericardium and with coronary epicardial and intramyocardial necrotizing vasculitis and superimposed occlusive and subocclusive thrombosis. Recurrence of unexplained early pleuropericardial effusion and mild intramyocardial vasculitis should raise the suspicion of PTLD requiring reduction of immunosuppression, even in the setting of negative intramyocardial cellular infiltrate and tissue EBV-negative molecular assessment.

New flux based dose-response relationships for ozone for European forest tree species.

To derive O3 dose-response relationships (DRR) for five European forest trees species and broadleaf deciduous and needleleaf tree plant functional types (PFTs), phytotoxic O3 doses (PODy) were related to biomass reductions. PODy was calculated using a stomatal flux model with a range of cut-off thresholds (y) indicative of varying detoxification capacities. Linear regression analysis showed that DRR for PFT and individual tree species differed in their robustness. A simplified parameterisation of the flux model was tested and showed that for most non-Mediterranean tree species, this simplified model led to similarly robust DRR as compared to a species- and climate region-specific parameterisation. Experimentally induced soil water stress was not found to substantially reduce PODy, mainly due to the short duration of soil water stress periods. This study validates the stomatal O3 flux concept and represents a step forward in predicting O3 damage to forests in a spatially and temporally varying climate.