P205 PROGNOSTIC VALUE OF AMYLOID–Β (1–40) IN PATIENTS WITH ACUTE MYOCARDIAL INFARCTION

Background

Survivors of acute myocardial infarction (AMI) have an increased risk of various cardiovascular complications during follow–up; therefore, adequate risk stratification remains the main challenge in the clinical setting. Amyloid β 1–40 (Aβ (1–40)) has already emerged as a negative prognostic marker for cardiovascular mortality, both in patients with stable chronic coronary artery disease and in patients with NSTEMI–type infarction. This is probably due to the pro–inflammatory and pro–atherosclerotic role of this peptide.

Methods

Plasma Aβ (1–40) values were tested acutely in a large prospective cohort of patients hospitalized for AMI (both NSTEMI and STEMI). The primary end–point was defined as all–cause mortality during the period of follow–up.

Results

894 individuals were enrolled in the study (607 with STEMI and 287 with NSTEMI). The median plasma concentration of Aβ (1–40) at the time of admission was 96.59 (60.94–134.5) pg/ml. During a median follow–up of 43 months, 123 patients died (primary endpoint). Higher Aβ (1–40) concentrations were associated with an increased risk of mortality, both on univariate analysis and after correction for other confounding variables. Furthermore, we found a strong positive correlation between plasma Aβ (1–40) values and age. The prognostic value of Aβ (1–40) was maintained only in the subgroup of patients with greater than the median age of 67 years.

Conclusions

This is currently the largest single–centre study evaluating the role of plasma Aβ (1–40) concentrations in predicting outcome in a population of patients admitted for AMI, both STEMI and NSTEMI. Our data represent a strong correlation between plasma (1–40) values and the increased risk of all–cause mortality during follow–up.

C53 DONOR–DERIVED CELL–FREE DNA (DD–CFDNA)–BASED ASSESSMENT OF CORONARY ALLOGRAFT VASCULOPATHY IN HEART TRANSPLANTED PATIENTS

Introduction

Cardiac Allograft Vasculopathy (CAV) is a leading cause of long–term graft dysfunction and failure after Heart Transplant (HTx). Early diagnosis is crucial to tailor therapeutic strategies. Despite advancements in cardiac imaging, the standard for CAV diagnosis remains coronary angiography. Donor–derived cell free DNA (dd–cfDNA) is a novel marker of graft injury in solid organ transplants. Elevations in dd–cfDNA levels may reflect CAV development during subclinical inflammation, thus it could represent a non–invasive method of surveillance for CAV rejection in apparently stable post–transplant patients. Given these premises, we decided to evaluate the potential of dd–cfDNA as alternative diagnostic biomarker for CAV.

Materials and Methods

31 blood samples from patients who underwent heart transplant at our institution in the last 10 years, were analyzed by Next Generation Sequencing (NGS) according to CareDx Alloseq protocol. The cfDNA was extracted starting from 2mL of plasma (Qiagen). Sequencing was performed on the Illumina Miseq platform. Troponin T (hs–TnT) and NT–proBNP (Brain Natriuretic Peptide) were measured by automated immunoassay analysers. All statistics were performed by STATA software and significance was set at p < 0.05.

Results

Heart transplant recipients were divided into 2 groups: 16 patients with known CAV status and 15 patients who had not (no–CAV). No significant differences between the two populations were observed, aside from time from HTx (177.28± 84.99 months in CAV vs 93.20 ± 84.39 months in no–CAV; p = 0.033). A significant difference in dd–cfDNA fraction was found between CAV and no–CAV patients (p = 0.03); with mean values of 0,41% e 0,13%, respectively. Neither NT-proBNP (p = 0.08) nor hs–TnT (p = 0.31) concentrations were significantly different between the two groups, but a positive correlation was found between the two biomarkers (r 0.6966; p = 0.0013). A trend of linear relationship emerged between cfDNA and NT-proBNP levels (r 0.4155; p = 0.08).

Conclusions

With this study, we demonstrated the feasibility of evaluating dd–cfDNA in long–term heart transplanted patients and its possible association with CAV development. Further investigations are warranted to explore a possible association between dd–cfDNA levels other circulating biomarkers and CAV progression. The definition of “homogeneous” subgroups of patients according to a “risk score” will allow to better manage their follow up and improve their prognosis.

Targeting the methyltransferase setd7 prevents myocardial ischemic injury: a translational study

Background

Despite appropriate revascularization strategies, a significant number of patients with myocardial infarction (MI) develop ischemic heart failure suggesting that breakthrough therapies are yet to be approved in this setting. Methylation of non-histone proteins is emerging as a central regulatory mechanism in health and disease. The methyltransferase SETD7 has shown to methylate and alter the function of a variety of proteins in vitro, however its function in the heart is poorly understood.

Purpose

In the present study we sought to determine the role of SETD7 in myocardial ischemic injury.

Methods

Neonatal rat ventricular myocytes (NRVM) were exposed to glucose deprivation (GD) for 15 h, in the presence of the selective SETD7 inhibitor [(R)-PFI-2] or its inactive enantiomer [(S)-PFI-2]. Western blot and real time PCR were employed to investigate the effects of energy stress on SETD7 and the Hippo pathway, while apoptosis and oxidative stress were assessed by Caspase-3 activity assay and mitochondrial swelling. YAP activity was assessed through chromatin immunoprecipitation assay (ChIP), its localization was examined by confocal microscopy while mono-methylation was assessed by immunoblotting. Expression of YAP-dependent antioxidant genes was assessed by western blot. SETD7 knockout (SETD7−/−) mice and wild-type (WT) littermates underwent ischemia/reperfusion (I/R) injury. Rats underwent permanent ligation of left anterior descending coronary artery (MI). Left ventricular (LV) myocardial samples were collected from mice undergoing I/R injury and patients with ischemic cardiomyopathy (ICM) and treated ex-vivo with (R)-PFI-2. SETD7 and antioxidant genes expression was assessed in peripheral blood mononuclear cells (PBMCs) from patients with ST-elevation MI (STEMI).

Results

We show that SETD7 is activated upon energy deprivation in cultured NRVMs and methylates the Hippo pathway effector YAP, leading to its cytosolic retention and impaired transcription of antioxidant genes. Pharmacological inhibition of SETD7 by (R)-PFI-2 restored YAP nuclear localization thus preventing mitochondrial reactive oxygen species (mtROS) and apoptosis. SETD7 deletion in mice attenuated I/R injury, mtROS and LV dysfunction by restoring YAP-dependent transcriptional programs. SETD7/YAP dysregulation was also observed in rats with MI and LV specimens from ICM patients. Of note, (R)-PFI-2 treatment prevented titin oxidation and myofilament stiffness in cardiomyocytes isolated from I/R mice and patients with ICM. Finally, SETD7 was upregulated in STEMI patients and its expression negatively correlated with antioxidant genes.

Conclusions

Targeting SETD7 may represent a valid therapeutic strategy to protect the heart during ischemia.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): University of Zurich

Comparison of clinical and pathological staging and long-term results of liver transplantation for hepatocellular carcinoma in a single transplant center

Liver transplantation (OLT) is a treatment for hepatocellular carcinoma (HCC) superimposed on cirrhosis provided that the disease meets defined criteria. The aim of the study was to evaluate our experience with respect to clinical and pathological staging and long-term results. From 1996 to 2005, 50 patients underwent OLT for HCC including 43 men (86%) and seven women (14%) of median age 57 years (range 37 to 67). All patients fulfilled the Milan criteria. The HCC diagnosis was based on preoperative imaging and alpha-fetoprotein levels; no tumor biopsy was performed. Upon histological examination of the resected specimens, we discovered 6 (12%) incidentalomas and 8 (16%) cases of no HCC. Finally we had 42 "true" HCC. Twenty-six patients (52%) have been downstaged and 10 (20%) upstaged by preoperative imaging; 15% were pT1, 45% were pT2, 27% pT3, and 13% pT4a. Twenty-six percent of cases exceeded the Milan criteria. One patient (pT4a) with microvascular invasion died of pulmonary metastases at 14 months after transplantation. No HCC recurrences within the liver have been encountered at a median follow-up of 20 months (range 0 to 80 months). Overall the estimated 1-, 3-, and 5-year survival rates were 83%, 77%, and 72%, respectively. One-, 3-, and 5-year estimated survival rates were 87%, 75%, and 75% for pT1, and pT2, and 75%, 67%, and 67% for pT3 and pT4a, respectively (P = .99). Based on our experience OLT for HCC has long-term results comparable to those without HCC despite the presence of a significant number of cases exceeding the Milan criteria upon pathological staging.

De Novo Malignancies After Kidney and Liver Transplantations: Experience on 582 Consecutive Cases

De novo malignancies after transplantation are a growing problem of solid organ transplant recipients, due to longer survival follow-up under chronic immunosuppression. The aim of this study was to analyze a population of 582 consecutive kidney (n = 382) and liver (n = 202) transplant recipients, who survived at least 12 months after transplantation, at a single transplant center for the development of de novo cancers. The incidence of de novo malignancies was 7% after both renal and liver transplantation. The median elapsed time from transplant to the diagnosis of de novo malignancy was 45 months (range 3 to 220) months for kidney and 37 months (range 12 to 101 months) for liver transplants. Skin cancers were the most common within renal recipients, while gastroenteric cancers were more frequently encountered in liver transplants. Oropharyngeal and upper digestive tract tumors were always associated with a history of chronic alcohol consumption in liver recipients. Liver transplant recipients treated for acute rejection had a worse cancer prognosis than patients without rejection 1- and 2-year survivals 83% and 63% versus 36% and 17% (P = .026). The estimated 1- and 2-year survival rates for all types of de novo malignancies were 79% and 66%, including 64% and 51% for solid organ tumors versus 89% and 89% for skin cancers and posttransplant lymphoproliferative disorder (PTLD) (P = .17) in renal transplants and 70% and 42%, including 57% and 28% for solid organ tumors versus 85% and 64% for skin cancers and PTLD (P = .43) in liver transplants respectively.

T-lymphoblastic lymphomas expressing the non-disulfide-linked form of the T-cell receptor gamma/delta: characterization with monoclonal antibodies and genotypic analysis

Three cases of T-lymphoblastic lymphomas (T-LL) expressing the T cell antigen receptor gamma delta (TCR gamma delta) are reported. All of them were CD3+/beta F1-/TCR delta 1+. Moreover, neoplastic cells reacted with the delta TCS1 monoclonal antibody (MoAb) which binds to the non-disulfide-linked form of the TCR gamma delta, but not with the BB3 MoAb which recognizes the disulfide-linked form of the TCR gamma delta. All cases showed a stage II cortical phenotype, eg, TdT+/CD1+/CD3+/CD5+/CD7+; two of them coexpressed CD4/CD8, while the other was CD4+/CD8-. Two cases were positive for CALLA and CD25. Immunogenotypic analysis showed evidence of T beta and C gamma 2 gene rearrangements in all three cases and immunoglobulin (Ig) gene rearrangements in two cases. Two patients presented with an anterior mediastinal mass and the third with a solitary inguinal lymphadenopathy. We suggest that these cases of TCR gamma delta+ T-LL may be derived from the small population (approximately 0.5%) of CD3+ cortical thymocytes which, in the normal human thymus, express the delta TCS1-reactive, non-disulfide-linked form of the TCR gamma delta.

[Intra-sinus echo: demonstration using direct intracavitary recording of the sinus potential]

The authors searched for intra-sinusal echos during electrophysiological investigation of 53 patients (41 men, 12 women, average age: 61 +/- 12 years). Cycles of sinus echos were recorded in 8 patients (15 per cent). The period during which sinus echos could be recorded was 125 ms (average 40.6 +/- 34 ms). Indirect assessment of sinus node function in patients with sinus echos was normal (corrected sinus node recovery time, estimated atrio-sino atrial conduction times using Narula's technique). A valid and reproducible direct recording of the sinus node potential was only possible in one patient. In this case the echo cycles were provoked by stimulation periods of between 440 and 320 ms (echo zone of 120 ms). All the echos obtained were preceded by a sinus node potential with a different duration and morphology to that observed during basal sinus cycles (respective sino-atrial conduction times 105 and 115 ms). In this patient we were also able to induce sinus echos after a single extrastimulus during the spontaneous rhythm. the echo zone was 130 ms and with a shorter coupling interval (310 ms) two successive sinus echos were recorded. The demonstration of intrasinusal echos by direct recording of the sinus node potential supports the experimental data of Allessie and Bonke on isolated right atrial tissues of the rabbit. Improvements in the technique of endocavitary direct recording of the sinus node potential in man should complete this data by showing the possibility of sinoatrial tachycardias due to reentry.

[Sinus node electric activity in prolonged atrial pauses in subjects with the sick sinus syndrome]

Sinus node electrogram (SNE) was recorded in 15 patients with sick sinus syndrome (SSS) in which prolonged atrial pauses were observed. The aim of this study was clarify the physiopathological mechanisms underlying atrial pauses as well as to evaluate the sensitivity of sinoatrial conduction time (SACT) directly measured on SNE and of SACT estimated with the indirect Strauss method with respect to the detection of SSS. The following results were obtained: Sinus electrical activity was recorded during atrial pauses (greater than or equal to 2 basic sinus cycle length) in all the 9 patients in which the pauses spontaneously occurred and in the 2 patients in whom the pauses of 2860 and 3190 msec were induced by atrial pacing. In one of these latter two patients, moreover, a complete electrical desynchronization was observed. In the remaining 4 patients in whom, pauses (greater than or equal to 3 sec) were induced by carotid sinus massage of in 3 no sinus electrical activity was detected on SNE while in 1 advanced sinus node desynchronization was observed. Direct sinoatrial conduction time was abnormally prolonged in 6 patients with SSS and indirect sinoatrial conduction time in 9 patients.

[The sinus node electrogram in the evaluation of atrial pauses]

The aim of this study was to establish the electrophysiological mechanism of atrial pauses, defined as a sudden lengthening of atrial cycle greater than or equal to 10% of its basal value. The sinus node electrogram (SNE) was recorded during electrophysiological study in 20 subjects. Satisfactory recordings of 64 pauses were obtained, 25 of which were spontaneous, 16 were induced by short periods of atrial pacing (AP) in normal subjects, whereas 23 atrial pauses were induced with the premature stimulation method. The basal sinus cycle and the one during the spontaneous pauses were measured from the upstroke slope on the SNE. The electrically induced pauses of the sinus cycle were measured from the artifact of the stimulus to the upstroke slope of the SNE of the first post-pacing beat. We have found that: 1-spontaneous atrial pauses correspond to a moderate slowing of the sinus cycle and to a depression of the sinoatrial conduction occasionally up to a second degree sinoatrial block. Only in subjects with sick sinus disease, the atrial pauses are induced by depression of the sinus automatism; 2-in normal subjects the AP results in a sinoatrial conduction delay; 3-the single extrastimulus regularly produces a moderate increase of the sinoatrial conduction time with variable but minimal effects on the sinus node automatism.

[The relationship between systolic time intervals and the electrocardiographic pattern in essential hypertension (author's transl)]

Systolic time intervals at rest and after exercise were studied in 56 patients with essential hypertension. The patients were divided into groups according to the presence or absence at rest of electrocardiographic patterns of left atrial hypertrophy, and left ventricular strain. An impaired left ventricular function was shown, at rest and after exercise, in patients who had an electrocardiographic pattern of "left ventricular strain".