The suprachoroidal space in patients affected by retinitis pigmentosa

BACKGROUND AND OBJECTIVE

The Suprachoroidal Space (SCS) is a theoretical structure which can be demonstrated between the inner border of the sclera and the outer boundary of the choroid. SCS is being studied for its potential uses as a route for drug delivery and innovative surgical techniques for the treatment of many retinal diseases. Retinitis pigmentosa (RP) is a group of inherited eye disorders characterized by a gradual loss of photoreceptors, resulting in vision impairment, which typically presents as night blindness and progressive visual field loss. The purpose of the study is to define the morphology of outer choroidal margins by means of SS-OCT in RP.

MATERIAL AND METHOD

This is a retrospective observational study designed to evaluate the presence of SCS in RP. We performed Swept Source optical coherence tomography (SS-OCT) in a group of 55 patients affected by RP (26 males and 29 females, 110 eyes) with a mean age of 51.8 ± 13.7 years. In the control group, we included 28 healthy subjects (6 males and 22 females, 56 eyes) with a mean age of 48,8 ± 16,6 years.

RESULTS

OCT scans allowed the outer choroidal margin and inner scleral margin to be delineated with certainty in all 110 eyes. In the RP group SCS was detected in 47 of 110 eyes (42,7%), in the control group SCS was detected in 11 eyes (19,6%). Subjects with SCS visible (RP group) had reduced retinal thickness (168.4 µm) compared to those with not visible SCL (211.2 µm, P = .007).

CONCLUSIONS

SS-OCT can be successfully applied to assess the presence of SCS in RP and the high rate of SCS found in the RP patients is encouraging when considering future innovative therapies.

Hypertrophic cardiomyopathy in a dog: a systematic diagnostic approach

A seven-year-old female neutered Parson Russel Terrier was referred for syncopal episodes. An electrocardiogram revealed paroxysmal atrial flutter followed by periods of sinus arrest, suggesting sick sinus syndrome. Echocardiography showed severe biventricular wall thickening (hypertrophic cardiomyopathy (HCM) phenotype) with no signs of fixed or dynamic left ventricular outflow tract obstruction. Blood pressure, abdominal ultrasound, serum total thyroxin and thyroid-stimulating hormone, and insulin-like growth factor-1 were all within normal limits. Cardiac troponin I was elevated (1.7 ng/mL, ref<0.07). Serological tests for common infectious diseases were negative. A 24-h Holter confirmed that the syncopal episodes were associated with asystolic pauses (sinus arrest after runs of atrial flutter) ranging between 8.5 and 9.6 s. Right ventricular endomyocardial biopsies (EMB) were performed at the time of pacemaker implantation to assess for storage or infiltrative diseases that mimic HCM in people. Histological analysis of the EMB revealed plurifocal inflammatory infiltrates with macrophages and lymphocytes (CD3+ > 7/mm2) associated with myocyte necrosis, but no evidence of myocyte vacuolisation or infiltrative myocardial disorders. These findings were compatible with myocardial ischaemic injury or acute lymphocytic myocarditis. Molecular analysis of canine cardiotropic viruses were negative. The dog developed refractory congestive heart failure and was euthanised 16 months later. Cardiac post-mortem examination revealed cardiomyocyte hypertrophy and disarray with diffuse interstitial and patchy replacement fibrosis, and small vessel disease, confirming HCM. We described a systemic diagnostic approach to an HCM phenotype in a dog, where a diagnosis of HCM was reached by excluding HCM phenocopies.

Myocarditis and inflammatory bowel diseases: A single-center experience and a systematic literature review

BACKGROUND

Myocarditis and inflammatory bowel diseases (IBD) are rare conditions, but may coexist. Myocarditis in IBD may be infective, immune-mediated, or due to mesalamine toxicity. A gap of knowledge exists on the clinical features of patients that present myocarditis in association with IBD, especially for endomyocardial biopsy-proven cases. Our aims are: 1) to describe the clinical characteristics of patients with an associated diagnosis of myocarditis and IBD in a single-center hospital, 2) to perform a systematic review of the literature of analogous cases.

METHODS

We retrospectively analyzed data of patients followed up at the outpatient Cardio-immunology and Gastroenterology Clinic of Padua University Hospital, to identify those with an associated diagnosis of myocarditis and IBD. In addition, a systematic review of the literature was conducted. We performed a qualitative analysis of the overall study population.

RESULTS

The study included 104 patients (21 from our single center cohort, 83 from the literature review). Myocarditis in IBD more frequently affects young (median age 31 years) males (72%), predominantly with infarct-like presentation (58%), within an acute phase of the IBD (67%) and with an overall benign clinical course (87%). Nevertheless, a not negligible quote of patients may present giant cell myocarditis, deserve immunosuppression and have a chronic, or even fatal course. Histological evidence of mesalamine hypersensitivity is scarce and its incidence may be overestimated.

CONCLUSIONS

Our study shows that myocarditis in association with IBD, if correctly managed, may have a spontaneous benign course, but predictors of worse prognosis must be promptly recognized.

A Caged In-Source Laser-Cleavable MALDI Matrix with High Vacuum Stability for Extended MALDI-MS Imaging

Insufficient vacuum stability of matrix chemicals is a major limitation in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) of large tissue sample cohorts. Here, we designed and synthesized the photo-cleavable caged molecule 4,5-dimethoxy-2-nitrobenzyl-2,5-dihydroxyacetophenone (DMNB-2,5-DHAP) and employed it for lipid MALDI-MSI of mouse brain tissue sections. DMNB-2,5-DHAP is vacuum-stable in a high vacuum MALDI ion source for at least 72 h. Investigation of the uncaging process suggested that the built-in laser (355 nm) in the MALDI ion source promoted the in situ generation of 2,5-DHAP. A caging group is used for the first time in designing a MALDI matrix that is vacuum-stable, uncaged upon laser irradiation during the measurement process, and that boosts lipid ion intensity with MALDI-2 laser-induced postionization.

Experimental borosilicate bioactive glasses: pulp cells cytocompatibility and mechanical characterisation

AIM

To assess in vitro the effect of two novel phase separated borosilicate glasses (PSBS) in the system SiO₂ -B₂ O₃ -K₂ O-CaO-Al₂ O₃ on dental pulp cells; and to compare their bioactivity and mechanical properties to a conventional fluoroaluminosilicate glass namely FUJI IX.

METHODOLOGY

The cytocompatibility assessment of the two novel borosilicate glasses, one without alumina (PSBS8) and one containing alumina (PSBS16), was performed on cultured primary human pulp cells (hDPCs). Alamar blue assay was used to assess cell metabolic activity and cell morphology was evaluated by confocal imaging. The bioactivity in Stimulated Body Fluid was also evaluated after 1 and 3 weeks of immersion using SEM-EDX analysis. Vickers microhardness and flexural strength were assessed after incorporating the glass particles into a commercial glass ionomer cement liquid containing both polyacrylic and polybasic carboxylic acid.

RESULTS

The data revealed that the two borosilicate glasses enhanced cell viability ratios at all-time points in both direct and indirect contact assays. After 3 days of contact, PSBS8 without alumina showed higher viability rate (152%) compared to the PSBS16 containing alumina (145%) and the conventional glass ionomer particles (117%). EDX analysis confirmed an initial Ca/P ratio of 2.1 for 45S5K and 2.08 for PSBS8 without alumina after 3 weeks of immersion. The cement prepared using PSBS8 showed significantly higher Vickers hardness values (p=0.001) than that prepared using PSBS16 (46.6 vs 36.7 MPa). After 24 hours of maturation, PSBS8 (without alumina) exhibited a flexural strength of 12.9 MPa compared to a value of 16.4 MPa for the commercial control. PSBS8 without alumina had a higher strength than PSBS16 with alumina, after 1 and 7 days of maturation (p=0.001).

CONCLUSIONS

The present in vitro results demonstrated that the borosilicate bioactive glass without alumina enhanced pulp cell viability, spreading and acellular bioactivity better than the conventional glass ionomer cement and the experimental borosilicate glass containing alumina.

POS0887 CHORIORETINAL MICROVASCULAR INVOLVEMENT IN SYSTEMIC SCLEROSIS

Background

The optical coherence tomography angiography (OCTA) is a new non-invasive imaging technique that can detect flow and provide information about the vessel density (VD) at different layers in the eye. The ocular microvascular network has been only occasionally addressed as disease target in scleroderma (SSc) considering the relatively low prevalence of ocular symptoms in these patients.

Objectives

The study aims to evaluate retinal and choriocapillaris microvasculature in a group of SSc patients compared to matched controls (HC)and according to disease characteristics, capillaroscopy findings and pulmonary function tests.

Methods

VD was assessed through OCTA at the retinal superficial (SCP) and deep (DCP) capillary plexus, at the foveal avascular zone perimeter (FAZP) and at the choriocapillaris (CC) of 30 SSc patients compared to 30 sex- and age-matched subjects without any retinal disease.

Results

The SSc patients (age 57.3±10.0, female 86.7%) had diffuse cutaneous skin disease in 30.0% of the cases, an average disease duration of 10.4±7.2 yy, and anti-centromere and anti-Scl70 antibody positivity in 40.0%and in 30.0% of the cases, respectively. Compared to the HC, SSc showed an impaired VD at SCP (47.7±3.6 vs59.1±3.5%, p=0.009), DCP (50.0±6.7 vs 54.3±6.4%, p=0.015), FAZP (48.7±4.55 vs 51.0±3.55%, p=0.034) and CC(67.1±2.2 vs 68.6±1.7, p=.005). Moreover, in the SSc group, the presence of digital ulcers (46.7%),telangiectasias (43.3%) and interstitial lung disease (46.7%) was related to reduced VD at FAZP (46.8±4.1 vs50.3±4.3%, p=0.033), CC (66.1±1.4 vs 67.9±2.4%, p=0.004), and DCP (47.2±8.8 vs 51.9±4.3, p=0.004),respectively. Lastly, the average capillary density on capillaroscopy showed a positive correlation with VD at FAZP (r=0.474, p=0.008), DCP (r=0.414, p=0.023), and foveal CC (r=0.482, p=0.007) and there was also a correlation between CC and both DLco (r=0.467, p=0.009) and FVC/DLco (r=-0.436, p=0.004).

Conclusion

The SSc patients in our cohort showed lower ocular vessel density at different levels compared to HC. Furthermore, impaired VD at different levels of the eye correlates with the organ involvement and the degree of digital and pulmonary microvascular impairment. According to those data, the OCTA could be proposed as a biomarker tool to investigate the microvascular abnormalities in SSc.

Disclosure of Interests

None declared

Prognostic role of myocardial inflammation in patients with undefined left ventricular arrhythmogenic cardiomyopathy

Funding Acknowledgements

Type of funding sources: None.

Background

Etiology identification and risk stratification represent major issues for patients presenting with undefined left ventricular arrhythmogenic cardiomyopathy (ULVACM).

Purpose

To investigate the role of genetics and histology for ULVACM classification, management, and risk assessment.

Methods

We retrospectively analyzed a multicenter cohort of patients (screened n=1037) with ULVACM defined by ventricular arrhythmia (VA) onset, nonischemic late gadolinium enhancement (LGE) limited to the LV, and no severe dilated cardiomyopathy (LVEF≥40%). We selected patients undergoing both next generation sequencing (NGS) screening and endomyocardial biopsy (EMB) for etiology definition. When feasible, immunosuppressive therapy (IST) was used to target active myocardial inflammation (AMI). The study endpoint was a composite of cardiac death, heart transplantation and malignant VAs (VT, VF, appropriate ICD treatment).

Results

The study cohort is composed by 135 ULVACM patients (age 43±14 years, 63% males, LVEF 55±7 %). NGS identified pathogenic or likely-pathogenic variants (PVs/LPVs) consistent with ACM in 21 cases (16%), whereas EMB showed AMI in 78 patients (58%), including 13/21 PVs/LPVs+ (62%). After reclassification of 86 patients (64%), only 49 (36%) remained ULVACM. IST was started in 41/78 AMI patients (53%), including 9/13 PVs/LPVs+ (69%). Twenty patients (15%) met the study endpoint by 12 months, and 36 (27%) by the end of the study (60±27 months). Beyond malignant VT onset, AMI was the only predictor of events by 12 months (HR 5.0, 95%CI 1.4-18.1, p=0.007). No prognostic role was found for PVs/LPVs, except for the subgroup (n=77) with nonsustained VT onset. Among AMI patients, those treated by IST had a significantly lower occurrence of events, both by 12-months (1/41 vs. 16/37, p&lt;0.001) and later (HR 0.05, 95%CI 0.01-0.21, p&lt;0.001). Results were independently confirmed in PVs/LPVs+ and PVs/LPVs- cases. Excluding the IST population, the association of multiple factors among VT onset, PVs/LPVs, and AMI, resulted in an improved discrimination of arrhythmic risk profiles.

Conclusion

The combined genetic and histological workup allowed reclassification of up to 64% ULVACM patients, and substantially contributed into prognostic assessment. Furthermore, EMB identified suitable candidates for IST, who showed better outcomes irrespectively of their genotype.

Generation and phenotyping of a novel knock-in mouse model of desmoplakin dependent arrhythmogenic cardiomyopathy

Background

Arrhythmogenic Cardiomyopathy (AC) is a genetic cardiac disorder, mainly caused by mutations in genes encoding desmosomal proteins, and accounts for most stress-related arrhythmic sudden cardiac deaths (SCD) in the young and athletes. The AC myocardium is hallmarked by cardiomyocyte (CM) death and fibro-fatty replacement, which generate a pro-arrhythmogenic substrate. Several pathogenetic factors in AC remain obscure and better understanding of the disease mechanisms is required to develop novel efficacious therapies to prevent SCD, which are sorely missing.

The lexical analogy between desmosomes and desmosomal proteins has originally biased AC research towards CMs, the paradigmatic desmosome-bearing cells in heart. However, the myocardium is composed by different cell types, many of which express desmosomal proteins, albeit in the absence of desmosomes, including CMs, sympathetic neurons, vascular cells and fibroblasts. Notably, AC mutations are transmitted at germline, and thus may manifest in all cell types expressing desmosomal proteins. This might explain why the majority of preclinical AC models, using CM specific over-expression or deletion of the disease-causing mutation, failed to fully recapitulate the human disease phenotype.

Hypothesis

On these bases, we aimed to generate a knock-in (KI) AC mouse model for comprehensively studying AC pathogenesis.

Methods

As Desmoplakin (DSP) mutations occur in a large part of the Italian AC population, we used CRISP/Cas9 to generate a KI mouse strain harboring the Serine-to-Alanine substitution of S311, the murine homolog of human S299 [Bauce et al, 2005]. We successfully obtained DSPS311A/WT KI founders, which were viable and fertile and after backcrossing for &gt;10 generations, used to expand the new mouse strain. Mouse cardiac phenotype was characterized, at different stages (1,2,4,6,9 mo.) by functional (i.e. ECHO, telemetry-ECG, chronic exercise) and structural (i.e. EM, standard histology, confocal IF, TUNEL assay) analyses. Molecular/biochemical analyses probed the state of the main pathways involved in AC.

Results

Our analyses showed that, starting from 4 mo., DSP homozygous KI mice display contractile dysfunction, worsening during aging, and fibrotic myocardial remodelling with focal fatty lesions, accompanied by frequent arrhythmic beats, which become sustained ventricular arrhythmias upon Noradrenaline administration. Hearts showed desmosome alterations, particularly at advanced disease stages, and lateralization of cx43, which corresponded to the phenotype of human AC hearts. Heterozygous mice showed similar alterations, which only took longer to appear. Exercise accelerated disease progression and increased the incidence of SCD (DSPS311A: SCD=63%, n=11; ctrls: SCD=8%, n=12).

Conclusion

Our KI mice replicate the clinical and pathological phenotype of DSP-linked biventricular AC and are thus suited for the mechanistic study of the multicellular origin of the disease.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): PRIN Miur 2015

Transient visual blurring during a sexual intercourse in a young woman with surgically corrected myopia and unrecognized pigmentary glaucoma: A rare case report

PURPOSE

To present a rare case of unilateral visual loss episodes occurred during sexual intercourse in a young patient affected by unrecognized pigmentary glaucoma and previously undergone myopic refractive surgery.

CASE DESCRIPTION

The patient presented surgically flattened corneas and markedly asymmetric pigmentary glaucoma.

CONCLUSIONS

Previous refractive surgery, sexual intercourse, and athletic lifestyle might be risk factors for acute pigment dispersion and chronic progression of pigmentary glaucoma in young myopic patients. During their ophthalmic examination prior to refractive surgery, greater attention should be paid to detect early signs of pigmentary dispersion, and awareness of these dangerous situations should be raised in affected patients.

Predictors of death, heart transplantation and relapse in clinically suspected and biopsy-proven myocarditis in the pre-immunosuppression era

Background

Myocarditis is an infectious or autoimmune inflammatory disease of the myocardium; diagnosis relies on the exclusion of an acute coronary syndrome, and is confirmed by endomyocardial biopsy (EMB). Prognosis is highly variable, outcome predictors are not well defined.

Purpose

To identify clinical, imaging and immunological predictors of death, heart transplantation (HTx) and relapse in patients with myocarditis in the pre-immunosuppression era.

Methods

From 1993 to 2012 we consecutively enrolled 466 patients (68% male, mean age 37±17 years), 216 with clinically suspected and 250 with EMB-proven myocarditis. All patients underwent coronary angiogram and transthoracic echocardiogram, 44% of patients underwent cardiac magnetic resonance (CMR). Circulating auto-antibodies were measured in patients' sera by indirect immunofluorescence. All patients were prospectively followed-up at the local Cardio-immunology outpatient clinic.

Results

After a median follow-up of 50 months (IQR 25–75), 366 patients (79%) were alive, while 42 (9%) were dead or underwent HTx; 58 were lost to follow-up. Ten-year survival free from death or HTx was overall 83%, but was lower in patients with EMB-proven myocarditis (76% vs 94% in patients with clinically suspected myocarditis, p&lt;0.001). On univariate analysis, predictors of death and HTx were female gender (p=0.003), previous myocarditis (p=0.03), heart failure on presentation and advanced NYHA class (p&lt;0.001, respectively), histological diagnosis of giant-cell myocarditis (p=0.002), positivity for anti-heart antibodies (AHA, p=0.04), anti-cardiac endothelial cell (AECA, p=0.002) and anti-nucleus antibodies (ANA, p=0.003). On multivariate analysis, female gender (HR 2.69, p=0.02), lower left ventricular ejection fraction on echocardiogram (p&lt;0.001), positivity for high-titre organ-specific AHA (HR 4.1, p=0.02) and for ANA (HR 5.1, p&lt;0.001) were independent predictors of death and HTx. Seventy-seven patients had relapsing myocarditis; on univariate analysis, young age (p&lt;0.001), previous myocarditis (p&lt;0.001), symptoms preceding diagnosis (p=0.004), positivity for anti-intercalated disk autoantibody (AIDA, p=0.02), and presence of diffuse late gadolinium enhancement (LGE) on CMR (p&lt;0.001) were predictors of relapse. On multivariate analysis young age (p=0.02) and previous myocarditis (HR 8.4, p&lt;0.001) were independent predictors of relapse. Predictors of death, HTx and relapse, respectively, did not differ when considering separately patients with EMB-proven myocarditis and those with clinically suspected myocarditis.

Conclusions

In the pre-immunosuppressive era, young age and a previous episode of myocarditis were independent predictors of relapse, female gender, left ventricular dysfunction at presentation and high-titre organ-specific AHA and ANA were independent predictors of death and HTx, suggesting that autoimmune features in myocarditis predict worse prognosis.

Funding Acknowledgement

Type of funding source: None

Cardiac magnetic resonance features of left dominant arrhythmogenic cardiomyopathy: differential diagnosis with myocarditis

Objectives

To identify potential imaging features at cardiac magnetic resonance (CMR) specific for left-dominant arrhythmogenic cardiomyopathy (LDAC) diagnosis.

Materials and methods

Between January 2011 and May 2016, we considered 36 consecutive stable patients with a recent diagnosis of significant VA and ECG morphology consistent with a LV origin, detection of potential LV arrhythmic substrate at CMR, undergoing a clinically-indicated LV endomyocardial biopsy. Exclusion criteria were history of known cardiac disease, contraindications to CMR and impaired CMR image quality. After application of these criteria, in 9 patients endomyocardial biopsy showed tissue abnormalities consistent with the diagnosis of LDAC. From the same CMR-endomyocardial biopsy registry, a second group of 9 consecutive patients with a histological diagnosis of previous myocarditis were identified.

Results

Mid-wall LGE in the interventricular septum was detected in 5 myocarditis, without findings in LDAC group (p=0.03), whereas subepicardial LGE at the level of posterolateral wall of LV was detected in 8 cases of LDAC vs. 2 cases of myocarditis (p=0.02). Fat infiltration, and particularly subepicardial posterolateral fat infiltration, was found in all LDAC patients vs. one myocarditis only (p&lt;0.01). No differences in other CMR findings or in any clinical or echocardiographic parameters were found between patients with a biopsy consistent with LDAC vs. patients in whom biopsy suggested myocarditis.

Conclusions

In patients with significant VA and ECG morphology consistent with a LV origin, identification of morpho-functional involvement of the subepicardial layer of LV posterolateral wall at CMR (LGE, fat infiltration, wall dyskinesis) is consistent with a diagnosis of LDAC.

Funding Acknowledgement

Type of funding source: None

Immunosuppression and outcomes of myocarditis patients presenting with ventricular arrhythmias

Background

Effects of immunosuppressive therapy (IST) on ventricular arrhythmias (VA) have not been reported in immune-mediated biopsy-proven myocarditis patients. Furthermore, myocarditis arrhythmic risk is still unpredictable. The aim of our study was to evaluate effectiveness of IST on VA in myocarditis patients, and stratify their arrhythmic risk, using clinical and diagnostic features, including serum organ-specific anti-heart (AHA) and antiintercalated-disk autoantibodies (AIDA).

Methods

From a cohort of 498 consecutive patients, we enrolled 255 cases with biopsy-proven virus-negative myocarditis and evidence of VA (VF, VT, NSVT, and Lown's grade ≥2 PVC) at index hospitalization. Serum AHA and AIDA were detected by a standardised indirect immunofluorescence technique. Whenever accepted and non-contraindicated, IST was started. Controls (IST-) were chosen after 1:1 matching to IST+ cases by age, gender, ethnicity, left ventricular ejection fraction, VA type, and treatment. Prospective follow-up (FU), occurred at defined timepoints.

Results

58 matched patient couples (42±13 y, 67% males, 50% IST+) were analyzed in the main study cohort. Overall, 28 (24%) had VT, and 62 (53%) were discharged with ICD. IST duration was 12±1 months. No patients died and no serious complications from IST occurred. By 24-month FU, major VA occurred in 6 IST+ vs. 10 IST- patients (p=0.420), with no cases of VT following IST termination. As compared to IST- ones, IST+ patients showed a significant reduction in NSVT and PVC burden, as well as an improvement in clinical, laboratory and imaging findings (all p&lt;0.05). Major VA onset and positive AIDA status were independently associated with major VA at FU (HR 14.2, 95% CI 2.9–68.7, and 8.0, 95% CI 2.6–25.2, respectively, both p&lt;0.001). Furthermore, in the whole study population (N=255), IST played as an independent protective factor from major VA (HR 0.3, 95% CI 0.2–0.7, p=0.005) at 38±21 months FU.

Conclusions

In immune-mediated virus-negative myocarditis patients presenting with VA, IST is feasible and effective on NSVT and PVC burden, as well as on structural, laboratory and imaging endpoints. Short-term effects are limited on major VA, which were independently associated with major arrhythmic onset and positive AIDA, in keeping with the proposed etiopathogenetic involvement of autoimmunity in virus-negative myocarditis.

Funding Acknowledgement

Type of funding source: None

New Derivatization Reagent for Detection of free Thiol-groups in Metabolites and Proteins in Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry Imaging

Several diseases are associated with disturbed redox signaling and altered metabolism of sulfur-containing metabolites and proteins. Importantly, oxidative degradation of fresh-frozen tissues begins within the normal time scale of MALDI MSI sample preparation. As a result, analytical methods that preserve the redox state of the tissue are urgently needed for refined studies of the underlying mechanisms. Nevertheless, no derivatization strategy for free sulfhydryl groups in tissue is known for MALDI MSI. Here, we report the first derivatization reagent, (E)-2-cyano-N-(2-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)ethyl)-3-(4-hydroxyphenyl)acrylamide (CHC-Mal), for selective detection of free thiols using MALDI MSI. We performed in situ derivatization of free thiol groups from thiol-containing metabolites such as glutathione and cysteine and reduced proteins such as insulin and imaged their spatial distribution in porcine and mouse xenograft tissue. Derivatization of thiol-containing metabolites with CHC-Mal for MALDI MSI was also possible when using aged tissue in the presence of excess reducing agents. Importantly, CHC-Mal-derivatized low mass-metabolites could be detected without the use of a conventional MALDI matrix.

Bone remodeling and bone matrix quality before and after menopause in healthy women

Acceleration of remodeling activity after menopause leads to bone loss and fragility, however, whether this is associated with modifications of bone matrix quality has been less studied. The impact of variation in bone remodeling rate on bone matrix has been studied mainly in pathologies or anti-osteoporotic treatments. However, in healthy women this has been less studied. We analyzed, at the global level, bone matrix quality in bone biopsies from 3 groups of healthy women (20 per group): 1) before menopause (PreM), 2) 1 year after menopause (PostM, paired biopsies with preM), and 3) 14 (±9) years after menopause (LT-PostM). The mean degree of mineralization (DMB) and heterogeneity index (HI) of mineralization were assessed by X-ray microradiography on whole bone matrix; intrinsic properties (mineral/organic ratio, mineral maturity, mineral crystallinity, collagen maturity) were assessed by Fourier Transform Infrared microspectroscopy, microhardness by microindentation, both at a global level and calculated by mean of several measurements over the whole tissue area. In PostM compared to PreM (bone remodeling rate had doubled), mean DMB measured on the entire bone plane (whole bone matrix) of the sample was not different. HI was increased in trabecular bone indicating a higher heterogeneity of mineralization. However, in PostM, mineral/organic ratio (trabecular) and microhardness (cortical and trabecular) were decreased, whereas mineral/collagen maturation or crystal size/perfection were unchanged. Thus, in PostM, the local mineral content and microhardness were first affected. In LT-PostM (bone remodeling rate was 3 times higher), the mean DMB was still not different. However, the mineral/organic ratio, microhardness, mineral maturity, crystallinity all were lower compared to PreM and PostM, in both cortical and trabecular bone. Bone remodeling rate was negatively correlated with microhardness, DMB, mineral/organic and crystallinity. This suggests that increases in bone remodeling rates after menopause have a direct impact on bone quality by inducing the formation of more extensive "immature" bone areas, but the amount of immature bone does not cause modification of the global DMB.

P5557Cardiac autoantibodies and ventricular arrhythmias in patients with biopsy-proved myocarditis

Background

Cardiac autoandibodies have been associated with dilatative cardiomyopathy in subjects with inflammatory heart disease. However, their association with ventricular arrhythmias (VA) in patients with autoimmune myocardits has never been investigated so far.

Purpose

To evaluate the association between cardiac autoantibodies and both baseline and FU VA in patients with a de novo diagnosis of biopsy-proved autoimmune myocarditis.

Methods

We enrolled 44 consecutive patients (59% males, mean age 44±13y, mean LVEF 50±10%) presenting with symptomatic VA (VF, VT, NSVT, >1ehz746.0501 PVC/24h) and a de novo diagnosis of biopsy-proved autoimmune myocarditis according to the ESC criteria. Serum anti-heart (AHA) and anti-intercalated disk (AIDA) autoantibodies were assessed at a referral center at the time of the index hospitalization. Complete baseline data, including ECG, arrhythmia telemonitoring, echocardiogram, cardiac magnetic resonance (CMR) and blood biomarkers (T-troponin, NT-proBNP) were collected. The endpoint of the study was the occurrence of major VA (VT, VF, appropriate ICD shocks) at 5y FU, as assessed by 2/y Holter ECG monitoring and (when applicable) ICD interrogation.

Results

At baseline evaluation, 24 (55%) and 23 patients (52%) were AHA+ and AIDA+, respectively. Clinical onset with major VA was documented in 24 patients (55%): 9 AHA+ vs. 15 AHA- (p=0.017) and 13 AIDA+ vs. 11 AIDA- (p=0.547). At presentation, no significant differences were found between AHA+ vs. AHA- and AIDA+ vs. AIDA- patients in LVEDV, LVEF, T-troponin and NT-proBNP values (all p=n.s.). Positive (2/3) Lake Louise criteria at CMR were found in 33 patients (75%; p=n.s. among different subgroups). Before discharge, 27 subjects (61%) underwent ICD implant. Optimal medical treatment was started in all of the cases, with no significant differences in betablockers, antiarrhythmic drugs and immunsuppressive therapy, among different subgroups (all p=n.s.). Overall, 10 patients (23%) experienced major VA by 5y FU: 3 AHA+ vs. 7 AHA- (p=0.147) and 9 AIDA+ vs. 1 AIDA- (p=0.013). In particular, 18 events were documented (range 1–3 episodes per patient at 2.2±1.7 y mean FU), including 3 VT episodes and 15 appropriate ICD shocks. Taking together baseline and FU data, multiple (>1) major VA episodes occurred in 8 patients: 3 AHA+ vs. 5 AHA- (p=0.436) and 8 AIDA+ vs. 0 AIDA- (p=0.005). Of note, 3/3 AHA+ patients with multiple major VA espisodes were also AIDA+ (double positivity).

Conclusion

In biopsy-proved autoimmune myocarditis presenting with VA, major VA occurrence by 5y FU, as well as arrhythmias recurrences, are more common among AIDA+ patients. By converse, none of the isolated AHA+ cases experienced multiple episodes of major VA. These findings may suggest distinct pathophysiological mechanisms involving the different molecular targets of cardiac autoimmunity.

Acknowledgement/Funding

None

P3828Zebrafish models for arrhythmogenic cardiomyopathy type 8: a starting platform for exercise stress test and drug treatment

Background

Arrhythmogenic Cardiomyopathy (AC) is an inherited heart disease characterized by progressive substitution of the myocardium with fibro-fatty tissue, leading to electrical instability and high risk of sudden death, particularly in young subjects and athletes. In recent years, our laboratory has produced zebrafish (zf) mutant lines modelling AC type 8, an AC form linked to mutations in the junctional protein Desmoplakin (Dsp). Mutations in the DSP gene have been identified in both dominant and recessive AC cases, characterized by left-dominant and biventricular forms of the disease. Sports medicine has highlighted that they are the most dangerous forms, being less easily identifiable by ECG.

Purpose

Taking advantage of our zf Dsp mutant lines, we aim to fully characterize the pathological phenotype, analyze the perturbation of cell communication pathways, evaluate the role of the physical exercise, and test the efficacy of candidate drugs.

Methods

Among our zf lines we have identified double mutant animals, bearing both zf dspa and dspb mutations in heterozygous condition, as the best model able to recapitulate the human AC phenotype. This model underwent physical stress tests in the presence/absence of candidate drug treatment. Phenotyping included heart rhythm measurement, gene expression analysis using Real Time PCR and signaling pathway transgenes, immune-histochemistry, whole-mount in situ hybridization, standard histology and ultrastructural TEM analysis.

Results

Preliminary results from mutant phenotyping indicate alterations in heart rate, sudden cardiac death, structural alterations of the myocardium associated with junctional disorganization and, in parallel, dysregulation of Wnt, Hippo and TGFbeta pathways. Specifically, Dsp mutant animals can range from an 8% decrease to a 14% increase of heart rhythm compared to the physiological range (120–140 beats per minute in zf larvae). At the adult stage, about 1% of the fish mutant population dies suddenly. The histological examination shows a 50% reduction of the myocardial cell mass, in parallel with a 50% decrease of Dsp signal, detected by TEM, associated with the so-called “pale desmosome” phenotype. Signaling dysregulation includes an 80% loss of Wnt/Beta-catenin, a 300% increase of TGFbeta and a 500% increase of Hippo/YAP-TAZ signaling in the cardiac tissue. Physical stress tests and pathway-directed drug treatment have clarified that these factors can modulate the pathological phenotype, as preliminarily evidenced by the rescue of Wnt signal decrease to normal levels through SB216763 treatment of Dsp-deficient individuals at rest.

Conclusion

Preliminary evidences corroborate the zf organism as a suitable model for AC cellular and molecular phenotyping, exploitable for the dissection of the genetic events leading to the onset and progression of the disease, and applicable to the analysis of chemical and mechanical modulators of AC-associated features.

Acknowledgement/Funding

Cariparo 2017 SHoCD; TRANSAC; CPDA133979/13; RP-2014-ehz745.06700394

P5695Catheter ablation of ventricular tachycardia in patients with acute vs. previous myocarditis

Background

Ventricular tachycardias (VT) may occur late after myocarditis, as well as in the acute inflammatory phase of the disease. However, the role of catheter ablation (CA) in preventing VT recurrences in patients with acute (AM) vs. previous myocarditis (PM) has never been investigated so far.

Purpose

To evaluate the results of CA performed in patients presenting with VA and biopsy-proved myocarditis at different inflammatory stages.

Methods

We enrolled 46 consecutive patients (74% males, mean age 43±12y, mean LVEF 46±9%) with myocarditis and VT at index hospitalization. Based on endomyocardial biopsy and cardiac magnetic resonance (CMR) results, the patients were divided into AM and PM groups: in AM group, myocarditis was biopsy-proved, according to the ESC criteria; PM patients had a history of biopsy-proved myocarditis more than 12 months before, with no current signs of active inflammation (negative biopsy according to the ESC criteria; nonischaemic LGE at CMR with negative Lake-Louise criteria; absence of unexplained troponin abnormalities). ICD were implanted upon clinical indications. All of the patients underwent electroanatomical mapping (EAM) and VT CA. During 3 (2.5–3.5)y FU, VT recurrences were evaluated by 2/y Holter ECG and ICD interrogation.

Results

At baseline, 23 patients (50%) had AM, and 23 PM. Overall, 16 AM and 21 PM patients underwent ICD implant (p=n.s.). The clinical VT was monomorphic in 22 AM and 23 PM patients, respectively (p=n.s.) with a dominant right-bundle branch block with superior axis (RS) morphology in both groups (16 AM vs. 17 PM cases, p=n.s.). However, RS morphology was associated with left ventricular inferoposterior LGE at CMR in 9/16 AM vs. 17/17 PM patients (p=0.003). Similarly, inferoposterior localization of low-voltage areas at EAM was found in 11/16 AM vs. 17/17 PM patients (p=0.018). Furthermore, CMR showed a greater LGE transmural extension in AM patients (65±19%) as compared to PM ones (40±25%, p<0.001). Epicardial EAM and CA were performed in 14 AM vs. 15 PM patients, with endocardial-only approach adopted in the remaining cases (p=n.s.). VT CA was defined as successful (class A) in all of the subjets. However, during FU VT recurrences were documented in 7/23 AM vs. 0/23 PM patients (p=0.009). Four AM cases underwent redo CA late after myocarditis (1.5±0.3y after index hospitalization), with no further VT recurrences in FU.

Conclusion

In myocarditis patients presenting with VT, CA results are significantly better in PM cases as compared to AM ones. These findings are consistent with the different underlying substrate, and suggest the best role for ablation strategy after myocarditis healing.

Acknowledgement/Funding

None

P5563Biopsy proven myocarditis: clinical and instrumental predictors of adverse prognosis at presentation

Background

Myocarditis is an insidious and potentially fatal illness with different clinical presentations and an unpredictable course. Prompt recognition of high risk patients is of paramount importance in preventing major adverse events.

Purpose

To identify predictors of dismal prognosis in a large cohort of patients with biopsy proven myocarditis.

Methods

Univariate analysis was used to identify predictors of death and heart transplant in a prospective cohort of 366 patients with biopsy proven myocarditis (aged 38±17, male 66%) using student's test and contingency tables as appropriate.

Results

At the time of follow up 46 patients (13%) were dead or received heart transplant (DHTX), 283 (77%) were alive (A) and 37 (10%) lost at follow up. Age at presentation was 33±20 y in DHTX v.s 39±15 in A cohort (p=0.057). Clinical features predicting adverse prognosis included female gender (p=0.002), heart failure at presentation (p=0.000), NYHA class II to IV (p=0.000). Clinical and radiographic signs of both left and right heart failure suggested worse outcome (p=0.000) as well as ongoing anticoagulation therapy (p=0.009). On ECG right (R) or left (L) axis deviation was a strong predictor of events (p=0.000). From an echocardiography perspective the presence of mild to severe mitral regurgitation (p=0.03), reduced left ventricular systolic function (FE) (p=0.000), reduced right ventricular fractional area change (FAC) (p=0.035) was strongly correlated to death or heart transplant. On cardiac catheterization the variables predicting unfavourable outcome included reduced left ventricular systolic pressure (LVSP) (p=0.000), reduced mean aortic pressure (mAP) (p=0.002), increased mean right atrial pressure (RAP) (p=0.001), FE on angiography (p=0.000). On cardiac biopsy (Bx) negative predictors were giant cell histology type (p=0.000) and PCR positive for viral genome (p=0.02) particularly for parvovirus B19 (p=0.04), adenovirus (p=0.04), and Epstein Barr virus (EBV) (p=0.03). See Tab 1

Table 1

Conclusion

Female gender, HF like presentation, reduced LV and RV systolic function, R or L axis deviation on ECG, presence of viral PCR or giant cell histology on Bx, reduced LVSP and mAP; increased RAP may be useful parameters to identify high risk patients on presentation. This may increase clinical efforts and surveillance in this subgroup in order to reduce the incidence of major adverse events.

P4651Biopsy-proven myocarditis: independent predictors of dismal prognosis, relapse and role of immunosuppressive therapy

Background

Biopsy-proven myocarditis may be infectious or autoimmune. Risk stratification in biopsy-proven myocarditis and the role of immunosuppressive therapy in autoimmune forms have not been completely defined.

Purpose

To identify clinical, instrumental and immunological predictors of death, cardiac transplantation and relapse in a prospective cohort of 314 biopsy-proven myocarditis patients, and describe the effect of immunosuppressive treatment on secondary outcome measures, e.g. left ventricular ejection fraction (LVEF), in a subgroup of 45 consecutive patients with biopsy-proven autoimmune myocarditis diagnosed in our Cardiology Clinic.

Methods

Univariate and multivariate Cox regression analysis were used to identify predictors of death, heart transplant, and relapse in a cohort of 314 patients with biopsy-proven myocarditis (male 75%, median age 37). Actuarial survival free from death or transplant was calculated by the Kaplan-Meier method.

Results

Actuarial survival free from death or heart transplantation was 83% at 5 years. Among the clinical, instrumental and immunological features at diagnosis, independent predictors of death or heart transplantation by multivariable analysis were a lower transthoracic echocardiographic biplane LVEF% (p=0.001) and high serum titre for anti-nucler (ANA) and anti-cardiac endothelial cell autoantibodies (AECA). The only independent predictor of relapse was previous history of myocarditis. Immunosuppressive therapy was associated with a significantly favorable effect on LVEF (LVEF pre-therapy 37% (26; 50 interquartile range) vs. LVEF post-therapy 59% (48; 65 interquartile range), respectively, p=0.000).

Conclusions

In biopsy-proven myocarditis left ventricular dysfunction at diagnosis and autoimmune pathogenesis are associated with dismal prognosis, immunosuppressive therapy with improved LVEF in autoimmune patients.

Filling the gap between the OR and virtual simulation: a European study on a basic neurosurgical procedure

BACKGROUND

Currently available simulators are supposed to allow young neurosurgeons to hone their technical skills in a safe environment, without causing any unnecessary harm to their patients caused by their inexperience. For this training method to be largely accepted in neurosurgery, it is necessary to prove simulation efficacy by means of large-scale clinical validation studies.

METHODS

We correlated and analysed the performance at a simulator and the actual operative skills of different neurosurgeons (construct validity). We conducted a study involving 92 residents and attending neurosurgeons from different European Centres; each participant had to perform a virtual task, namely the placement of an external ventricular drain (EVD) at a neurosurgical simulator (ImmersiveTouch). The number of attempts needed to reach the ventricles and the accuracy in positioning the catheter were assessed.

RESULTS

Data suggests a positive correlation between subjects who placed more EVDs in the previous year and those who get better scores at the simulator (p = .008) (fewer attempts and better surgical accuracy). The number of attempts to reach the ventricle was also analysed; senior residents needed fewer attempts (mean = 2.26; SD = 1.11) than junior residents (mean = 3.12; SD = 1.05) (p = .007) and staff neurosurgeons (mean = 2.89, SD = 1.23). Scoring results were compared by using the Fisher's test, for the analysis of the variances, and the Student's T test. Surprisingly, having a wider surgical experience overall does not correlate with the best performance at the simulator.

CONCLUSION

The performance of an EVD placement on a simulator correlates with the density of the neurosurgical experience for that specific task performed in the OR, suggesting that simulators are able to differentiate neurosurgeons according to their surgical ability. Namely this suggests that the simulation performance reflects the surgeons' consistency in placing EVDs in the last year.

Choroidal Neovascular Membranes after Photodynamic Therapy: Ultrastructural Analysis of Two Surgically Excised Membranes

PURPOSE

To report on the ultrastructural electron microscopic findings of two surgically excised subfoveal choroidal neovascular membranes (CNV) that had undergone photodynamic therapy (PDT).

METHODS

Two patients underwent PDT because of subfoveal neovascular membranes (CNV). Due to enlargement of the CNV seen on fluorescein angiography three months after PDT, one patient underwent surgical excision of the membrane; the other patient underwent both surgical membrane excision combined with macular translocation one month after PDT. The membranes were examined under the transmission electron microscope (TEM).

RESULTS

The membranes were composed of a core and a rim, the latter being mainly composed of fibrin and collagen fibrils. The core was preeminently composed of endothelium-lined vascular channels associated with retinal epithelium cells. The endothelial cells of blood vessels appeared well-preserved.

CONCLUSIONS

The lack of histological signs of recanalization and vascular thrombosis may indicate that in our cases the enlargement of the CNVs seen on fluorescein angiography three months and one month respectively after PDT may originate mainly from reproliferation of choroidal vessels rather than recanalization of previously occluded vessels.

Type 1 primary hyperoxaluria: A case report and focus on bone impairment of systemic oxalosis

Primary hyperoxaluria is a rare genetic disorder characterized by oxalate overproduction, leading to kidney failure due to nephrocalcinosis, and is eventually responsible for systemic oxalosis. Bone impairment, secondary to oxalate deposits, is one of the many complications that may occur. Skeletal involvement can be difficult to diagnose because of lack of clinical symptoms and therefore needs to be confirmed by invasive testing, such as transiliac bone biopsy. If confirmed, bone oxalosis is the proof of disease severity and that combined liver-kidney transplantation should be performed.