OC-057 PREVENTION OF INCISIONAL HERNIAS BY PROPHYLACTIC MESH-AUGMENTED REINFORCEMENT OF MIDLINE LAPAROTOMIES FOR ABDOMINAL AORTIC ANEURYSM TREATMENT. 5-YEAR FOLLOW-UP OF A RANDOMIZED CONTROLLED TRIAL

Introduction

The incidence of incisional hernias (IHs) after open repair of an abdominal aortic aneurysm (AAA) is high. Several randomized controlled trials have reported favorable results with the use of prophylactic mesh to prevent IHs, without increasing complications. In this analysis we report on the results of the 60-month follow-up of the PRIMAAT trial (Ann Surg 2016; 263(4): 638–45).

Methods

In a prospective, multicenter, open label, randomized design, patients were randomized between prophylactic retrorectus mesh reinforcement (MESH group), and primary closure of their midline laparotomy after open AAA repair (NOMESH group). This article reports on the results of clinical follow-up after 60 months. If performed, ultrasonography or computed tomography were used for the diagnosis of IHs.

Results

Of the 120 randomized patients, 114 were included in the intention-to-treat analysis. Thirty-three patients in the NOMESH group (33/58–56.9%) and 34 patients in the MESH group (34/56–60.7%) were evaluated after 5 years. The cumulative incidence of IHs in the NOMESH group was 32.9% after 24 months and 49.2% after 60 months. No incisional hernias were diagnosed in the MESH group. In the NOMESH group, 21.7% (5/23) underwent reoperation within 5 years due to an IH.

Conclusion

Prophylactic retrorectus mesh reinforcement after midline laparotomy for the treatment of AAAs safely and effectively decreases the rate of IHs. The cumulative incidence of IHs after open AAA repair, when no mesh is used, continues to increase during the first 5 years after surgery, which leads to a substantial rate of hernia repairs.

Proteomic analysis of exercise-induced hypertrophy reveals sex-related mitochondrial differences mediated by AMPK

Background

Regular physical activity results in characteristic structural and functional changes in the heart, which are collectively referred to as the athlete's heart. However, the extent of exercise-induced left ventricular (LV) hypertrophy and functional changes show significant differences between men and women, the molecular background of which is not fully elucidated.

Objective

The aim of this study was to provide a proteomic characterization of long-term, intense exercise-induced LV myocardial hypertrophy in a rat model, with a focus on sex-related differences.

Methods

Our rats were divided into trained (FEx) and control female (FCo) as well as trained (MEx) and control male (MCo) groups. In the trained groups, athlete's heart was induced by a 12-week swimming protocol. Myocardial hypertrophy was confirmed by echocardiography and functional adaptation by pressure-volume analysis. Proteomic measurements based on liquid chromatograph-coupled mass spectrometry were performed on proteins isolated from our LV myocardial samples.

Results

Echocardiography and post-mortem myocardial mass showed significant LV hypertrophy in both sexes, which was more pronounced in female animals (tibial length normalized LV muscle mass: + 17.4% MEx vs. MCo, + 31.0% FEx vs. FCo). LV contractility increased to the same extent in both sexes. Relative expression of 3074 proteins were determined by proteomics. There was a significant change in expression of 229 proteins in males and 599 in females compared to the level of same-sex controls. Based on our gene ontological analysis, physiological LV remodeling in females is characterized by increased expression of proteins in mitochondrial function (cellular respiration and fatty acid oxidation) and biogenesis, whereas in males, proteins that bind to the actin cytoskeleton is primarily increased. Further investigation revealed that the quantity of AMP-activated protein kinase (AMPK) and sirtuin 3 (SIRT3) was increased only in female animals.

Conclusions

Our data suggests that physiological LV hypertrophy resulting from regular, balanced exercise is associated with sex-specific changes in the myocardial proteome. The main differences might be associated with different regulation of mitochondrial function and biogenesis, related to AMPK pathway. Our results contribute to the understanding of the development of physiological myocardial hypertrophy.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Bolyai János Research Scholarship (BO/00837/21) to OANational Research, Development and Innovation Office (NKFIH) K135076 to B.M.

Pressure overload and volume overload-induced chronic heart failure are associated with characteristic left ventricular myocardial proteomic alterations

Introduction

Hemodynamic overload induces pathological remodeling of the left ventricle (LV) and eventually heart failure (HF). The two types of chronic hemodynamic stress, namely pressure overload (PO) and volume overload (VO) evoke characteristically different functional and structural alterations in the myocardium. Nevertheless, whether PO- and VO-induced HF are also associated with distinct LV proteomic alterations has not been investigated yet.

Aim

Hence, we thought to perform a proteomic analysis on LV myocardial samples from rat models of PO- and VO-induced HF.

Methods

PO–induced HF was evoked by transverse aortic constriction (TAC). VO–induced HF was established by creating an aortocaval fistula (ACF). Age-matched sham-operated animals served as controls for TAC (ShamT) and ACF (ShamA), respectively. Pressure-volume (P-V) analysis, echocardiography, histology and quantitative real-time PCR were carried out to provide a detailed characterization of the two HF models. Peptides obtained via the digestion of myocardial proteins with trypsin and LysC were labeled with isobaric tags (TMT16) and measured with LC-MS/MS in a bottom-up explorative proteomic approach. Differential expression and gene ontology enrichment analysis (GO:BP) was carried out on summarized protein reporter ion intensities.

Results

In both the TAC and ACF groups, presence of typical signs and symptoms of HF (dyspnea at rest, fatigue, ascites) increased lung-to-tibial length ratio and elevated LV natriuretic peptide mRNA expression levels confirmed the development of advanced HF. Furthermore, the TAC model was associated with massive wall thickening, concentric LV hypertrophy (LVH), marked interstitial fibrosis and substantially impaired active relaxation and passive filling (slope of end-diastolic P-V relationship: 0.103±0.015 vs. 0.023±0.003mmHg/μl, TAC vs. ShamT, P<0.001). In contrast, the ACF model was predominantly characterized by LV dilatation, eccentric LVH, moderate fibrosis and severely reduced LV contractility (slope of end-systolic P-V relationship: 0.5±0.1 vs. 2.3±0.3mmHg/μl, ACF vs. ShamA, P<0.001). Proteomic analysis revealed that out of the 4691 identified and quantified proteins, 1404 and 913 have shown upregulation, while 1359 and 886 downregulation in the TAC and ACF groups respectively compared to their corresponding sham groups. GO:BP analysis has indicated that the downregulation of mitochondrion organization, ATP metabolic processes and oxidative phosphorylation and the upregulation of actin cytoskeleton organization were the most profound alterations in the TAC model. In contrast, the ACF model was associated with robust downregulation of fatty acid oxidation and upregulation of endocytosis, defense and immune response on the proteomic level.

Conclusions

PO and VO-induced advanced HF are not only associated with characteristically different functional and structural remodeling but also with distinct LV proteomic alterations.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Research, Development and Innovation Office (NKFIH) of Hungary

Clinical determinants of non-invasive global myocardial work index before and after transcatheter aortic valve implantation: a prospective study

 

The estimation of non-invasive global myocardial work indices is a novel method of the left ventricular (LV) functional assessment, which may overcome the load-sensitvity of the traditional functional measures. The diagnostic and prognostic role of this approach may gain particular importance in pressure overload states, such as in patients with severe aortic stenosis. However, the longitudinal changes of this recently introduced measure are scarcely investigated, and data are also lacking about the main determinants of these measures.

Accordingly, our aim was to investigate the clinical determinants of preoperative and also postoperative GMWI in patients undergoing transcatheter aortic valve replacement (TAVR).

Fifty patients (62% male, age: 78±5 years) were enrolled. Prior to the procedure, subjects underwent echocardiographic investigation and the detailed medical history was also recorded. Speckle-tracking analysis was performed and global longitudinal strain (GLS) was measured. LV pressure curve was estimated by adding the mean aortic valve gradient to the systolic blood pressure. Using these measures, global myocardial work index (GMWI) and global constructive work index (CMWI) was quantified by commercially available software. A 6 months follow-up examination was also performed and at that time point we determined the aforementioned parameters.

At follow-up, GLS has significantly increased (−13.0±4.1 vs. −14.8±3.8%; p<0.001), while GMWI was significantly lower compared to baseline (1789±748 vs. 1506±561 mmHg%, p<0.01). CMWI did not differ between the two time points (2309±782 vs. 2086±609 mmHg%, p=0.11). Using multivariable analysis, age (β=0.30; p<0.05) preoperative New York Heart Association (NYHA) class (β=−0.48; p<0.001) and having a pacemaker (β=−0.44; p<0.01) were found to be independent predictors of the preoperative GMWI (R2=0.39; overall p<0.001). On the other hand, postoperative GMWI was determined (R2=0.48; overall p<0.001) by gender (β=−0.25; p<0.05), the presence of diabetes mellitus (β=−0.37; p<0.01) and also by having a pacemaker (β=−0.38; p<0.01).

TAVR significantly alters LV functional measures. Different clinical factors influence GMWI before and after the procedure: age, NYHA class-based symptom severity and having a pacemaker were found to be independently associated with preoperative GMWI, while gender, the presence of diabetes mellitus and pacemaker device are the most important clinical determinants of the postoperative GMWI value.

Funding Acknowledgement

Type of funding sources: None.

Right ventricular mechanics and its association with symptoms in transcatheter aortic valve replacement candidates: a three-dimensional echocardiography study

 

Aortic valve stenosis is one of the most prevalent valvular disease with significant clinical burden. While it is initially a disorder of the left ventricle (LV), long-term effects of the disease also affect the right ventricle (RV) as well. Nevertheless, data are scarce regarding the changes of RV mechanics and their association with symptomatic status of the patients. 3D echocardiography allows a more detailed assessment of the RV, which may unveil distinct changes of its morphology and function in this clinical setting.

Accordingly, our aim was to examine LV and RV mechanics in TAVR candidate patients with severe aortic stenosis using three-dimensional (3D) echocardiography.

Seventy patients (51% male, age: 80±6 years) were enrolled. Detailed medical history and symptomatic status were obtained. Beyond conventional transthoracic echocardiographic protocol, 3D loops were also acquired. We measured 3D LV and RV end-diastolic volume indexed to body surface area (EDVi), ejection fraction (EF) and global longitudinal (GLS) using dedicated software. Furthermore, we have determined 3D RV global longitudinal (RV GLS) and circumferential strain (RV GCS) using the ReVISION method.

LV EF (r=0.28, p<0.05) and LV GLS (r=−0.26, p<0.05) significantly correlated with age, while RV EF (r=0.21, p=0.11), RV GLS (r=−0.17, p=0.19) and RV GCS (r=−0.07, p=0.61) did not show association with it. 41% (n=29) of the patient population mentioned angina or had syncope. Patients with these symptoms had comparable LV EDVi (73±23 vs. 69±25 mL/m2, p=0.47), LV EF (47±15 vs. 51±10%, p=0.14) and LV GLS (−13.6±4.8 vs. −14.8±2.6%, p=0.25) to those who did not mention these complaints. On the other hand, patients with angina or syncope in their medical history had significantly lower RV EDVi (58±13 vs. 70±23 mL/m2, p<0.05), while having significantly higher RV EF (46±10 vs. 52±7%, p<0.05). Moreover, symptomatic patients had significantly lower RV GCS (−15.7±5.6 vs. −19.6±5.3%, p<0.01), while RV GLS did not differ (−15.8±4.8 vs. −17.4±4.1%, p=0.17).

Patients with severe aortic stenosis have marked changes in not only the LV, but the RV mechanics as well. While the symptomatic status does not seem to be associated with LV morphology and function, patients with angina or syncope had distinct changes in RV size and the contraction pattern of the chamber.

Funding Acknowledgement

Type of funding sources: None.

Pharmacological selectivity of SGLT2 inhibitors and cardiovascular outcomes in patients with type 2 diabetes: a meta-analysis

Background

Sodium-glucose cotransporter 2 (SGLT2) inhibitors reduce major adverse cardiovascular events (MACE) in patients with type 2 diabetes mellitus. However, SGLT2 inhibitors show great variance in pharmacological selectivity to SGLT2 over SGLT1. Reduced functional capacity of SGLT1 is associated with lower risk of heart failure development and mortality in humans. Yet, the clinical relevance of additional pharmacological SGLT1 inhibition is unclear.

Purpose

To assess whether additional pharmacological SGLT1 blockade adds further benefits to SGLT2 inhibition.

Methods

In this preregistered meta-analysis, we included randomized placebo-controlled cardiovascular outcome trials (CVOTs) of SGLT2 inhibitors assessing MACE (composite of cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke) in patients with type 2 diabetes. Hazard ratios (HRs) and 95% confidence intervals (CIs) of prespecified clinical endpoints were pooled using a random-effects model. Interactions were assessed according to low versus high pharmacological SGLT2 selectivity of the given medication. Mixed-effects meta-regression analysis was performed to quantify correlation between pharmacological SGLT2:SGLT1 selectivity ratio and clinical outcomes.

Results

A total of 6 independent CVOTs comprising 57553 type 2 diabetic patients (mean age 64.6±7.9 years; 36769 [63.9%] men) were included. Overall, SGLT2 inhibitors significantly reduced risk of adverse cardiovascular and renal outcomes, but had no significant impact on the risk of fatal and nonfatal stroke compared with placebo (HR, 0.92; 95% CI, 0.77–1.10; p=0.36; I2=63%). Agents with clinically relevant SGLT1 inhibitory effect (sotagliflozin, canagliflozin) significantly reduced the risk of stroke (HR, 0.78; 95% CI, 0.64–0.94) compared with placebo, whereas those with high SGLT2 selectivity did not (HR, 1.06; 95% CI, 0.92–1.22), yielding a significant interaction (p=0.018). The difference was also significant in patients with estimated glomerular filtration rate (eGFR) lower than 60 mL/min/1.73 m2 (p=0.047). Meta-regression indicated that lower SGLT2:SGLT1 pharmacological selectivity ratio was associated with lower risk of stroke (pseudo-R2=78%; p=0.011), which was evident even after adjusting for baseline eGFR values (p=0.047). Pharmacological selectivity of SGLT2 inhibitors had no significant impact on any other assessed clinical outcomes, including hospitalization for heart failure and all-cause death.

Conclusion

These hypothesis-generating results indicate that targeting SGLT1 in addition to SGLT2 inhibition might constitute a new avenue for stroke risk reduction in patients with type 2 diabetes. Further confirmatory studies are needed.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This project was supported by grants from the National Research, Development and Innovation Office (NKFIH) of Hungary (K134939 to T.R.), and by the New National Excellence Program of the Ministry of Human Capacities of Hungary (ÚNKP-21-3-II-SE-45 to A.A.S.).

Evaluation of the interplay between NASH and HFpEF in varied murine age groups

Funding Acknowledgements

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Union's Horizon 2020 Research and Innovation Programme, grant agreement no. 739593

New National Excellence Program of the Ministry of Human Capacities (ÚNKP-21-3-II)

Introduction

Heart failure with preserved ejection fraction (HFpEF) is characterized by diastolic dysfunction, left ventricular hypertrophy, left atrial enlargement and increased serum levels of NT-pro-BNP. HFpEF accounts for 50% of heart failure cases, and typically develops in patients with metabolic comorbidities. Non-alcoholic fatty liver disease and subsequent steatohepatitis (NAFLD, NASH) is the most common chronic liver disease developing due to obesity. Although clinical/epidemiological data exists in humans showing that NASH may lead to cardiac dysfunction per se, experimental data in this regard is lacking.

Purpose

We aimed to evaluate whether NASH is an independent factor of cardiac dysfunction and to investigate the age-dependent effects of NASH on cardiac function.

Methods

Middle aged (10 months old) and aged (24 months old) C57Bl/6J mice were fed either control diet or Choline Deficient (CDAA) diet over a period of eight weeks. Young (2 months old) mice were used as a control. Before termination, echocardiography was performed. Upon termination, organs were isolated for further analysis.

Results

CDAA diet lead to the development of NASH in both age groups, without inducing weight gain, allowing us to investigate the direct effects of NASH on cardiac function. Left ventricular end-diastolic volume (EDV) was increased in aged animals, compared to young and middle aged animals, suggesting increased ventricular pressure. Aged animals were characterized by increased posterior wall thickness (PWT) during diastole and by increased LV mass, indicating left ventricular hypertrophy. Assessment of ejection fraction showed an age-dependent decline. Pulse wave and tissue Doppler measurements showed no difference in E/e’ ratio between the groups. However, strain analysis showed that diastolic dysfunction developed only in aged mice due to NASH.

Conclusion

We conclude that there were no observed changes in cardiac diastolic function due to NASH when using standard echocardiographic evaluation; however, the more sensitive method of strain analysis with 2D speckle tracking was able to show evidence of diastolic dysfunction due to NASH in aging animals.

Sex-related proteomic differences of the athlete's heart

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Bolyai János Research Scholarship - BO/00837/21 to O.A., National Research, Development and Innovation Office (NKFIH) of Hungary - K135076 to B.M.

Introduction

Regular physical activity results in characteristic structural and functional changes in the heart, which are collectively referred to as the athlete’s heart. However, the extent of exercise-induced left ventricular (LV) hypertrophy and functional changes show significant differences between men and women, the molecular background of which is not fully elucidated.

Purpose

The aim of this study was to provide a proteomic characterization of long-term, intense exercise-induced LV myocardial hypertrophy in a rat model, with a focus on sex-related differences.

Methods

Our rats were divided into trained (FEx) and control female (FCo) as well as trained (MEx) and control male (MCo) groups. In the trained groups, athlete’s heart was induced by a 12-week swimming protocol. Myocardial hypertrophy was confirmed by echocardiography and functional adaptation by pressure-volume analysis. Proteomic measurements based on liquid chromatograph-coupled mass spectrometry were performed on proteins isolated from our LV myocardial samples.

Results

Echocardiography and post-mortem myocardial mass showed significant LV hypertrophy in both sexes, which was more pronounced in female animals (tibial length normalized LV muscle mass: + 17.4% MEx vs. MCo, + 31.0% FEx vs. FCo). LV contractility increased to the same extent in both sexes. Relative expression of 3074 proteins were determined by proteomics. There was a significant change in expression of 229 proteins in males and 599 in females compared to the level of same-sex controls. Based on our gene ontological analysis, physiological LV remodeling in females is characterized by increased expression of proteins in cellular respiration and fatty acid oxidation, whereas in males, proteins that bind to the actin cytoskeleton is primarily increased.

Conclusions

Our data suggests that physiological LV hypertrophy resulting from regular, balanced exercise is associated with sex-specific changes in the myocardial proteome. Our results contribute to the understanding of the development of physiological myocardial hypertrophy.

Exercise-induced right ventricular alterations in a rodent model of athletes heart

Funding Acknowledgements

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): János Bolyai Research Scholarship of the Hungarian Academy of Sciences (BO/00837/21) to AO

National Research, Development and Innovation Office (NKFIH) of Hungary (K120277 and K135076 to BM)

Background

Intense sports activity leads to the adaptation of cardiac structure and function, the so-called athlete’s heart. Research over the last years has focused on exercise-induced adaptation of the right ventricle (RV), because the disproportionate load on the RV - when compared with left ventricle - might lead to pathological consequences, such as interstital fibrosis or chamber dilation.

Purpose

We aimed at investigating right ventricular alterations induced by regular aerobic exercise training in a rat model of athlete's heart.

Methods

Young, adult rats were divided into control (Co) and exercised (Ex) groups. Trained rats swam 200 min/day for 12 weeks. In vivo electrophysiological study and in vitro force measurements on isolated permeabilized cardiomyocytes were carried out to investigate electrical and functional alterations, respectively. Molecular biological (qRT-PCR, Western-blot) and histological investigations were applied to reveal underlying mechanisms.

Results

Exercise training was associated with increased RV cardiomyocyte width (12.5±0.1µm Co vs. 13.8±0.2µm Ex, p<0.05) and corresponding hyperphosphorylation of protein kinase B (Akt). RV myofilaments from exercised animals showed increased maximal force development and improved calcium sensitivity. Sarcomere protein investigations revealed marked overall and site-specific hypophosphorylation of troponin I.  We found prolonged QT interval and right ventricular effective refracter period (RVERP: 44.0±1.6ms Co vs. 52.8±2.1ms Ex, p<0.05) along with decreased gene expression of potassium channels. Picrosirius staining did not reveal fibrosis, that was underlied by unchanged protein expression of connective tissue growth factor (CTGF) and gene expression of profibrotic markers. Gene expression of apoptotic markers and fetal gene program did not differ between the groups.

Conclusions

According to our data, regular swim training induced RV hypertrophy, that was associated with functional improvement adn hypophosphorilation of troponin I. Prolonged repolarization without pathological alterations in RV myocardial tissue suggest physiological remodeling after balanced training.

Immune checkpoint inhibition with PD-1 inhibitor induces cardiac dysfunction without overt myocarditis in C57BL/6J mice

Funding Acknowledgements

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Union’s Horizon 2020 Research and Innovation Programme under grant agreement no. 739593

“Semmelweis 250+ Kiválósági PhD Ösztöndíj” (EFOP-3.6.3-VEKOP-16-2017-00009)

Gedeon Richter Talentum Foundation’s scholarship

Background

Immune checkpoint inhibitors have revolutionized the treatment of several form of malignancies (including metastatic melanoma) by enhancing the cytotoxic effects of T cells against cancer cells. Cancer cells evade immune surveillence by increasing the expression of T cell inhibitory molecules, also known as immune checkpoints, such  as programmed cell death-1 (PD-1). Pharmacological inhibition of these molecules by immune checkpoint inhibitors (ICI) will enhance the antitumor activity of T cells. However, enhanced T cell activity may cause immune related adverse effects, including cardiotoxicity.

Aims

We aimed to investigate the effect of PD-1 inhibition on cardiac function and the underlying mechanisms in mice.

Methods

8-10 weeks old C57BL6/J mice were treated with isotype control or anti-PD-1 antibody for 2 or 4 weeks. Cardiac function and morphology was assessed by echocardiography and histology, while the transcriptomic changes were analyzed via RNA sequencing. Nitrosative stress in the heart was assessed by immunohistochemistry and qRT-PCR. Inflammatory gene expression alterations were determined by qRT-PCR in the heart and thymus.

Results

Small animal echocardiography revealed cardiac dysfunction even after 2 weeks of anti-PD-1 treatment, with distinct transcriptomic changes. Nitrosative stress was found to be elevated in the myocardium due to anti-PD-1 treatment, however, histological and qRT-PCR analysis did not reveal T cell infiltration into the myocardium and only mild inflammation was seen in the heart. In contrast, inflammatory gene expression was significantly enhanced in the thymus of anti-PD-1-treated animals, where interleukin-17 showed the most prominent increase.

Conclusions

These findings characterize cardiac dysfunction as a form of ICI-induced cardiotoxicity, which may be mediated by increased thymic inflammatory activation and cytokine production.

Left ventricular SGLT1 expression is upregulated in heart failure in humans and rat model

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Research, Development and Innovation Fund of Hungary;

Ministry of Human Capacities of Hungary

Introduction

Myocardial sodium-glucose cotransporter 1 (SGLT1) has been shown to contribute to cardiac pathological processes, whereas humans with functionally limited SGLT1 are at lower risk of developing heart failure (HF). The novel HF medications, SGLT2 inhibitors, non-selectively inhibit SGLT1 to different extent, therefore, characterization of its expression in disease conditions is relevant.

Purpose

To investigate left ventricular (LV) SGLT1 expression in humans with end-stage HF, and in a rat model of HF.

Methods

Myocardial LV samples were harvested from control subjects (Controls, n=9) undergoing valve surgery, and from patients with end-stage dilated cardiomyopathy (DCM, n=12) undergoing heart transplantation. The rat model of aorto-caval fistula (ACF, n=12) was used to induce HF with predominant LV dilation in rats during a course of 24 weeks; sham-operated animals served as controls (Sham-A, n=12). Echocardiography was used to assess LV structure and function prior to surgery in humans, as well as in rats at the end of the follow-up period. Western blotting was performed to characterize LV SGLT1 protein expression and to investigate the activity of the master regulators AMPK and ERK1/2. The extent of LV nitro-oxidative stress was quantified by immunohistochemistry (3-nitrotyrosine) in rats with HF.

Results

Both humans with DCM and rats with ACF-induced HF presented with severely dilated LVs compared to respective controls, whereas LV SGLT1 protein expression was significantly upregulated similarly by ~1.7-fold in both cases (both P<0.01). These increases in SGLT1 expressions were accompanied by significant reductions in ERK1/2 activating phosphorylation (both P<0.05), whereas AMPK activity was unaffected. In rats with HF, LV SGLT1 expression correlated significantly with the extent of myocardial nitro-oxidative stress (r=0.762, P=0.037).

Conclusions

LV SGLT1 expression is upregulated in HF in both humans and small animals, and ERK1/2 shows a concomitantly reduced activity. LV SGLT1 expression correlates with the extent of nitro-oxidative stress, suggesting a possible pathological role in HF. Whether SGLT2 inhibitors exert direct cardiac actions via inhibition of myocardial SGLT1 needs to be elucidated.

The development of systolic heart failure in case of pressure overload-induced left ventricular myocardial hypertrophy is associated with a unique microRNA expression profile in a rat model

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): New National Excellence Program of the Ministry of Human Capacities

Introduction

Growing body of evidence suggests that distinct alterations in myocardial microRNA (miRNA) expression contribute to pressure overload (PO)-induced pathological cardiac remodeling. Nevertheless, it is still under intense investigation whether the changes in miRNA expression patterns are also associated with the decompensation of LV systolic function in case of PO-evoked LV hypertrophy (LVH). Hence, we aimed to characterize miRNA expression in PO-induced LVH with and without systolic heart failure (HF).

Methods

PO was evoked by abdominal aortic banding (AB) in male Sprague-Dawley rats. Age-matched, sham-operated animals served as controls. Functional and morphological alterations were assessed by echocardiography and histology. At the end of the experimental period, rats in the AB group were subcategorized based on ejection fraction [EF] into ABLVH (EF>40%) and ABHF groups (EF<40%). Global miRNA expression profiling was performed using next generation sequencing. Bioinformatics analysis was carried out to predict miRNA-target interactions. Expression of selected target genes was measured by qRT-PCR.

Results

Increased heart weight-to-tibial length, LV mass and fibrosis confirmed the development of pathological LVH in both the ABLVH and ABHF groups. Nevertheless, increased lung weight-to-tibial length, chamber dilatation and severely reduced EF was noted only in the ABHF and not in the ABLVH, when compared to the sham group. 50 miRNA showed different expression in the ABHF compared to the ABLVH group. Based on the altered gene expression profile, in silico bioinformatics analysis predicted several target genes. Among them, reduced mRNA expression level of Fmr1 (FMRP translational regulator 1), Zfpm2 (zinc finger protein, multitype 2), Wasl (WASP like actin nucleation promoting factor), Ets1 (ETS proto-oncogene 1) and Atg16l1 (Autophagy Related 16 Like 1) was confirmed in ABHF compared to ABLVH.

Conclusions

Decompensation of systolic function in PO-induced LVH is associated with unique miRNA profile leading to specific regulation of gene expression.

Changes of the non-invasive myocardial work in patient undergoing transcatheter aortic valve replacement: the influence of left bundle branch block

Funding Acknowledgements

Type of funding sources: None.

Patients with left bundle branch block (LBBB) are known to have substantially increased afterload sensitivity. It gains particular importance in subjects with aortic stenosis: patients with pre-existing LBBB may benefit more from interventions such as transcatheter aortic valve replacement (TAVR) by an effective and rapid reduction of the left ventricular (LV) pressures.

Accordingly, our aim was to investigate the changes of LV myocardial work indices in patients undergoing TAVR by the presence of preoperative LBBB. Non-invasive myocardial work indices are novel echocardiographic parameters which adjust LV deformation to the instantaneous LV pressure, overcoming the the load-sensitivity of the traditional LV functional measures.

Thirty patients undergoing TAVR were enrolled (37% female; age: 78±6 years; aortic valve area [AVA]: 0.7±0.3 cm2). Fourteen patients (47%; LBBB group) showed LBBB pattern on ECG, by demonstrating native LBBB (n=6; 20%) or having ventricular pacing dependency (n=8; 27%), while 16 patients had narrow QRS (53%; non-LBBB group). Prior to the procedure, subjects underwent a detailed echocardiographic investigation. Speckle-tracking analysis was performed and global longitudinal strain (GLS) was measured. LV pressure curve was estimated by adding the mean aortic valve gradient to the aortic systolic pressure. Using these measures, LV global constructive work index (CMWI) and global work efficiency (GWE). were quantified by commercially available software. A 6 months follow-up examination was also performed and at that time point we determined the aforementioned parameters.

As expected, AVA significantly improved after the procedure in the pooled study group (1.8±0.4 cm2; p<0.001). GLS also significantly increased (-13.2±4.2 vs. -15.2±3.9 %; p<0.01), while CMWI only showed a tendential decrease (2422±788 vs. 2166±640 mmHg%; p=NS) at the follow-up. GLS (-10.6±3.7 vs. -15.5±3.4%; p<0.001), CMWI (1877±679 vs. 2898±529 mmHg%; p<0.001), and also GWE (82±9 vs. 91±4%; p<0.01) was significantly lower in the LBBB-group compared to the non-LBBB patients. At the follow-up, GLS was still significantly lower in the LBBB patients (-13.2±4.6 vs. -16.9±2.1%; p<0.01), however, CMWI was comparable between the two groups (1956±776 vs. 2350±439 mmHg%, p=NS).

Pressure overload of the LV may affect patients with LBBB substantially more than subjects without it. TAVR causes an immediate and significant decrease in the LV afterload, which results in a more pronounced improvement in the LBBB group compared to those with no LBBB.

Left ventricular SGLT1 expression correlates with the extent of myocardial nitro-oxidative stress in rat models of heart failure

Introduction

Recently, selective sodium glucose cotransporter 2 (SGLT2) inhibitors have been shown to reduce hospitalization for heart failure (HF) in patients with HF, irrespective of type 2 diabetes mellitus (T2DM). The mechanism of action is currently unclear as SGLT2 is not expressed in the heart. Unlike selective SGLT2 inhibitors, the dual SGLT1/2 inhibitor sotagliflozin not only reduced hospitalization for HF, but also decreased the risk of myocardial infarction, suggesting cytoprotective action. Even though SGLT1 it highly expressed in the sarcolemma of cardiomyocytes, its pathophysiological role is unclear. Previous studies have postulated that SGLT1 propagates nitro-oxidative stress in cardiomyocytes through NADPH oxidases.

Purpose

We aimed to assess myocardial left ventricular (LV) SGLT1 protein expression in two rat models of chronic heart failure and assess possible downstream effectors.

Methods

We evoked chronic HF in male rats by pressure overload using transverse aortic constriction (TAC, n=7) or by volume overload using aorto-caval fistula (ACF, n=7). Respective sham operated animals (Sham-T or Sham-A, both n=7) served as controls. At the end of the protocol, LV function was assessed using echocardiography and invasive pressure-volume analysis. Myocardial protein expression analysis was performed by western blotting, whereas nitro-oxidative stress was quantified by immunohistochemical staining for 3-nitrotyrosine (3-NT).

Results

In both TAC and ACF, systolic and diastolic dysfunction was evident, whereas LV mass was significantly increased compared with respective controls. The LV protein expression of SGLT1 was significantly upregulated in both HF models (∼1.5-fold increase, both P<0.01). Whereas the phosphorylation of ERK1/2 was decreased only in ACF, AMPKα activity was significantly reduced in both types of HF. The protein expression of the Nox4 NADPH isoform was substantially upregulated in both TAC and ACF (both P<0.01). The expression of SGLT1 and Nox4 showed a strong positive correlation in the Sham-T plus TAC (r=0.855, P<0.001) and Sham-A plus ACF (r=0.798, P=0.001) cohorts, respectively. Furthermore, SGLT1 expression positively correlated with the extent of myocardial nitro-oxidative stress as assessed by 3-NT staining (Sham-T plus TAC: r=0.833, P=0.015; Sham-A plus ACF: r=0.762, P=0.037).

Conclusions

LV SGLT1 protein expression was upregulated in both pressure and volume overload-induced HF, irrespective of aetiology, and correlated significantly with Nox4 expression and with the extent of myocardial nitro-oxidative stress. These suggest that SGLT1 might play an important role in the pathophysiology of HF. Future studies should elucidate the possible link between the upregulation of SGLT1 in HF and the increase of myocardial nitro-oxidative stress, so that the salutary effects of the dual SGLT1/2 inhibitor sotagliflozin could be partially explained.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Research, Development and Innovation Fund of Hungary (NVKP_16-1-2016-0017)Ministry for Innovation and Technology in Hungary (2020-4.1.1.-TKP2020)National Research, Development and Innovation Office (NKFIH) of Hungary (K134939 to TR)

Exercise training induces benign right ventricular hypertrophy along with functional improvement and without pathological processes or arrhythmogenicity in a rodent model of athletes heart

Introduction

Regular sport activity leads to the adaptation of cardiac structure and function, the so-called athlete's heart. Research projects over the last years have focused on exercise-induced adaptation of the right ventricle (RV), because the disproportionate load on the RV - when compared with the left ventricle - might lead to pathological consequences, such as myocardial interstital fibrosis or chamber dilation.

Purpose

We aimed at investigating comprehensively RV alterations induced by regular aerobic exercise training in a rat model of athlete's heart.

Methods

Young, adult rats were divided into control (Co) and exercised (Ex) groups (n=12–12). Exercised rats underwent a 12-week-long swim training program. In vivo electrophysiological study and in vitro cellular force assessments on isolated cardiomyocytes were carried out to investigate electrical and functional RV alterations, respectively. Molecular biological (qRT-PCR, Western-blot) and histological investigations were applied to reveal underlying mechanisms.

Results

Exercise training was associated with increased RV cardiomyocyte diameter (12.5±0.1 μm Co vs. 13.8±0.2 μm Ex, p<0.05), that was associated with hyperphosphorylation of protein kinase B (Akt). RV cardiomyocytes from exercised animals showed improved calcium sensitivity and increased maximal force development, that was associated with hypophosphorylation of troponin I. We found increased length of repolarization as reflected by prolonged QT interval and ventricular effective refracter period (VERP: 44.0±1.6 ms Co vs. 52.8±2.1 ms Ex, p<0.05) along with decreased gene expression of potassium channels (Kcnd2, Kcnj2). We could not induce ventricular arrhythmia by programmed stimulation. Picrosirius staining did not reveal fibrosis, that was associated with unchanged protein expression of connective tissue growth factor (CTGF) and gene expression of profibrotic markers (such as TGF-β). Gene expression of apoptotic markers (Bax, Bcl-2) and fetal gene program (such as β-MHC) did not differ between groups.

Conclusions

According to our data, regular swim training induced RV hypertrophy, that was associated with functional improvement (improved calcium sensitivity and maximal force), hypophosphorylation of troponin I and prolonged repolarization without characteristic pathological alterations or arrhythmogenicity of RV myocardial tissue.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Research, Development and Innovation Office of Hungary

Different myocardial microRNA expression patterns are observed in pressure overload- and volume overload-induced chronic heart failure

Introduction

MicroRNAs (miRNA) are short, single-stranded non-coding RNA molecules that regulate gene expression on the post-transcriptional level. Dysregulation of distinct miRNAs has been found to contribute to the development of chronic heart failure (CHF). However, whether distinct types of CHF are associated with different miRNA expression patterns is debated.

Aim

To characterize left ventricular (LV) miRNA expression in rat models of pressure overload (PO) versus volume overload (VO)-induced CHF.

Methods

Transverse aortic constriction (TAC) was performed to evoke PO-induced CHF. Aortocaval fistula (ACF) was created to establish VO-induced CHF. Age-matched sham-operated rats served as controls for TAC (ShamT) and ACF (ShamA), respectively. Pressure-volume analysis, echocardiography, histology and quantitative real-time PCR were carried out to assess alterations of the LV. Global miRNA expression profiling was performed using Nanostring technology. Bioinformatics analysis of differentially expressed miRNAs was also carried out to predict relevant miRNA-target interactions.

Results

Reduced LV systolic function (ejection fraction: 38±5 vs. 65±2% TAC vs. ShamT, 55±3 vs. 67±3%, ACF vs. ShamA, P<0.01) as well as elevated myocardial B-type natriuretic peptide and increased β-to-α myosin heavy chain gene expression confirmed the development of pathological remodeling and CHF in both models. Nevertheless, characteristic differences could be observed in LV morphology and ultrastructure. Accordingly, the TAC model was associated with robustly increased wall thickness, concentric LV hypertrophy and marked fibrotic remodeling. On the contrary, LV dilatation, eccentric LV hypertrophy and moderate fibrosis were the main morphometric findings in the ACF model. A group of miRNA (rno-miR-130a, 132, 199a-5p, 21, 210, 27b, 326) showed similar alterations in both phenotypes of CHF. However, other miRNAs demonstrated unique (specific to TAC: rno-miR-148b-3p, 150, 199a-3p, 203, 23b, 27b, let-7e; specific to ACF: rno-miR-140, 142-3p, 17-5p, 195, 20a, 204, 214, 27a, 29b, 322, 365, 425, 450a, let-7i) LV expressional changes in distinct phenotypes of CHF. In silico bioinformatics analysis revealed that the altered miRNA expression pattern predominantly controls the cardiac neural crest cell development, the inositol-phosphate pathway and the expression of microtubules-binding proteins. In contrast, alterations in the expression of genes responsible for redox state and epithelial-mesenchymal transition were modified only in the ACF group. Despite of the different signaling cascades, expression of Arhgap12 (Rho GTPase activating protein 12) was predicted to be strongly inhibited in both CHF models.

Conclusions

PO and VO-induced CHF are associated with unique miRNA expression patterns, which drive different signaling pathways. miRNA-controlled downregulation of Arhgap12 might represent a common feature in both phenotypes of CHF.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): ÚNKP-20-4-II-SE-20/New National Excellence Program of the Ministry of Human CapacitiesNVKP_16-1–2016-0017 (“National Heart Program”) National Research, Development and Innovation Fund of Hungary

Functional and proteomic investigation of potential role of steroid hormones in regulating early cardiac recovery in a rat model of isoproterenol induced intermittent myocardial ischemia

Introduction

Women benefit from higher levels of protection from cardiovascular diseases until menopause, after which they gradually lose their privileged status. Pivotal role of sex hormones, primarily estrogens were the focus of interest in explaining this clinical observation. Estradiol (E2) was a prime target of these investigations showing promising results. Nonetheless the potential influence of other estrogens and numerous estrogen metabolites have so far been neglected.

Purpose

The aim of our study was to investigate the influence of circulating steroid hormones on early functional and proteomic changes following repeated ischemic periods in female rats by applying the highly unbiased methods of in vivo pressure-volume analysis and mass spectrometry based proteomics.

Methods

Diffuse subendocardial ischemia was induced in female (F-Isch) Wistar rats with sc. injection of isoproterenol (ISO, 85mg/kg) daily for two consecutive days, while the control group (F-Co) received an equivalent volume of sc. saline solution. 48 hours after the first injection pressure-volume analysis (P-V) was carried out to assess left ventricular function. FFPE tissue slides were scanned and analyzed digitally, while peptides from the snap frozen left ventricular myocardium were measured by liquid chromatography-tandem mass spectrometry using isobaric labeling (TMT11plex). Serum and plasma samples were taken to measure circulating steroid hormone levels with mass spectrometry.

Results

Two day induction of ischemia resulted in 17% mortality in F-Isch. ISO treatment resulted in significant myocardial tissue damage compared to controls as assessed by histology. Ischemia led to a prominent impairment of diastolic aspects (active relaxation and myocardial stiffness) of left ventricular function (Tau: 11.1±0.7 vs. 16.1±1.1 F-Co vs. F-Isch; EDPVR: 0.05±0.005 vs. 0.131±0.016 F-Co vs. F-Isch.). Unsupervised hierarchical clustering performed on P-V parameters identified two distinct subgroups of F-Isch with severe or mild functional impairment. Supervised PLS-DA analysis of P-V and hormone datasets found three estrogens that might play a role in determining functional outcomes (2-Hydroxyestrone: 2-OHE1, 4-Hydroxyestrone: 4-OHE1, 4-Methoxyestrone: 4-MeE2). PLS analysis followed by gene ontology enrichment associated E2 and 2-OHE1 concentrations with mitochondrial protein expressions, while 4-OHE1 seemed to influence the reassembly of contractile structures after ischemia.

Conclusions

Our study has highlighted 2-OHE1 and 4-OHE1 as well as E2 as potentially influential estrogens on early post-ischemic recovery both on functional and on proteomic level.

Funding Acknowledgement

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): New National Excellence Program of the Ministry of Human Capacities of Hungary (ÚNKP-20-3-I-SE-1 to BA. B.) National Research, Development and Innovation Office (NKFIH) of Hungary (K134939 to T. R.)

Pursuing the non-invasive assessment of cardiac contractility: the added value of pressure-area-strain loop analysis in volume overload-induced heart failure

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This work was supported by the New National Excellence Programme (ÚNKP-19-3-I) of the Ministry for Innovation and Technology in Hungary, and the Artificial Intelligence Research Field Excellence Programme of the National Research, Development and Innovation Office of the Ministry of Innovation and Technology in Hungary.

Background

Global longitudinal strain (GLS) by speckle-tracking echocardiography (STE) is a sensitive parameter of left ventricular (LV) systolic function. Nevertheless, GLS is dependent on loading conditions. Through the analysis of pressure-strain loops, myocardial work was recently introduced and tested in different clinical scenarios. Myocardial work incorporates afterload, but still, it neglects changes in preload and LV geometry.

Purpose

Accordingly, our aim was to test our hypothesis that adding instantaneous LV size to myocardial work calculation can further mitigate the load-dependency of GLS, and therefore, a better correlation with intrinsic myocardial contractility can be achieved.

Methods

Volume overload-induced heart failure was established by an aortocaval fistula (ACF) in male Wistar rats (n = 12). Age-matched sham-operated animals served as controls (n = 12). STE was performed to assess GLS, which was immediately followed by invasive pressure-volume (P-V) analysis to assess LV pressure and to compute a gold-standard index of cardiac contractility (preload recruitable stroke work [PRSW]). Global myocardial work index (GMWI) was calculated from GLS and the invasively measured LV pressure. To compute GMWI indexed to LV area (GMWIA), the instantaneous power (calculated by multiplying the strain rate and the instantaneous LV pressure) was divided by the instantaneous LV area, and then it was integrated from mitral valve closure until mitral valve opening.

Results

LV ejection fraction did not differ significantly (ACF vs. controls: 59 ± 4 vs. 65 ± 9%, p = NS), whereas GLS (Figure 1A - representative animals) was slightly decreased in the ACF group (-13.2 ± 2.3 vs. -15.4 ± 1.9%, p < 0.05). In contrast, PRSW, GMWI (Figure 1B - representative animals) and GMWIA (Figure 1C - representative animals) were considerably reduced in ACF compared to controls (57 ± 13 vs. 111 ± 38mmHg, 1383 ± 382 vs. 1928 ± 281mmHg%, 11.6 ± 3.7 vs. 47.9 ± 22.8mmHg%/mm2, all p < 0.01). GLS showed moderate correlation with PRSW (r=-0.550, p < 0.01), whereas GMWI correlated more significantly, but still moderately with the invasively measured LV contractility (r = 0.681, p < 0.001). Correlation between the pressure-area-strain loop-derived GMWIA and P-V analysis-derived PRSW (Figure 1D) was found to be very strong (r = 0.924, p < 0.001).

Conclusions

In the case of LV volume overload-induced heart failure, our pressure-area-strain loop-derived metric reflected LV contractility better than GLS and even GMWI. Therefore, the incorporation of instantaneous LV size into myocardial work calculation represents a promising clinical tool to assess and monitor intrinsic myocardial function independently of loading conditions.

Abstract Figure 1

Myocardial work index better reflects contractility than longitudinal strain in rat models of pressure- and volume overload-induced heart failure

Funding Acknowledgements

Type of funding sources: None.

Speckle-tracking echocardiography (STE)-derived global longitudinal strain (GLS) is considered to be a sensitive marker of left ventricular (LV) function in a wide variety of cardiovascular diseases. Still, evidence suggests that GLS is significantly influenced by loading conditions. Myocardial work index (MWI) evaluates myocardial deformation in the context of afterload through the interpretation of strain in relation to instantaneous LV pressure. MWI may potentially overcome the limitations of mere strain calculation, and may better reflect cardiac contractility in hemodynamic overload states.

Accordingly, our aim was to examine the relationship of GLS and MWI with load-independent markers of LV contractility in rat models of pressure- and volume overload-induced heart failure.

Male Wistar rats underwent transverse aortic constriction (TAC; n = 12) to generate LV pressure overload, or aortocaval fistula (ACF; n = 12) was established to induce severe LV volume overload. In case of the control groups, sham procedures were performed (n = 12/12). Echocardiography loops were obtained to determine STE-derived GLS and global MWI. Pressure-volume analysis with transient occlusion of the inferior vena cava was carried out to calculate preload recruitable stroke work (PRSW), as a load-independent „gold-standard" parameter of LV contractility.

GLS was mildly reduced in the ACF group (-13.2 ± 2.4 vs. -15.4 ± 2.0%, p < 0.05), while it was significantly lower in TAC group compared to controls (-7.0 ± 2.8 vs. -14.5 ± 2.5%; p < 0.001). In contrast with these findings, PRSW and also MWI were significantly reduced in ACF (58 ± 14 vs. 111 ± 40 mmHg; 1328 ± 411 vs. 1934 ± 308 mmHg%, both p < 0.01), however, they were comparable between TAC and the corresponding sham group (110 ± 26 vs. 116 ± 68 mmHg; 1687 ± 275 Hgmm% vs. 1537 ± 662 Hgmm%; both p = NS). In the pooled population, GLS did not show relationship with PRSW (r=-0.23; p = 0.12), while MWI showed significant correlation with it (r = 0.70; p < 0.001).

GLS is significantly influenced by loading conditions, therefore, in case of severe pressure- or volume overload it may not be a reliable marker of LV contractility. In our rat model of pressure overload induced heart failure, contractility was maintained despite decreased GLS, while in the model of volume overload induced heart failure, GLS was maintained despite decreased contractility. MWI reflects contractility in hemodynamic overload states, therefore, it may be a more suitable marker of systolic function.

Abstract Figure. Pressure-strain loops of the groups

Atrial fibrillation is not associated with altered left atrial microRNA expression profile in ischemic end-stage human heart failure

Introduction

In patients with chronic heart failure (CHF) left ventricular dysfunction results in elevated left atrial (LA) pressure, triggering pathological atrial remodelling and atrial fibrillation (AF). Nevertheless, it has been reported that some patients with CHF remain in sinus rhythm (SR) despite of the pathological structural alterations (e.g. dilation and fibrosis) of the LA. Of particular interest, data is scarce regarding the molecular explanation for the observed variability in AF development among CHF patients. Recent studies have indicated that alterations in microRNA (miRNA) expression might contribute to the pathogenesis of AF. However, the majority of previous studies focusing on miRNA expression compared healthy LA with SR to pathologically remodelled, dilated LA with AF. Consequently, whether dysregulation of miRNA expression directly contribute to AF and not only to pathological LA remodelling has not been tested before.

Purpose

The present study aimed to investigate miRNA expression in comparably remodelled LA from end-stage CHF patients with permanent AF (CHF-AF) or SR (CHF-SR).

Methods

LA samples were collected from male, non-diabetic, ischemic end-stage CHF patients undergoing heart transplantation (n=24). Patients were carefully selected to avoid any differences in age (55±2 vs. 54±2 years, CHF-AF vs. CHF-SR, n.s.), ejection fraction ([EF]: 22.5±1.8 vs. 23.3±2.5%, CHF-AF vs. CHF-SR, n.s.) LA diameters (longitudinal LA diameter: 56±4 vs. 48±5mm.; CHF-AF vs. CHF-SR, n.s.; horizontal LA diameter: 61±2 vs. 54±3, CHF-AF vs. CHF-SR, n.s.) and NYHA stage. As a molecular marker of atrial load, the mRNA expression of atrial natriuretic peptide (ANP) was measured with qRT-PCR. The extent of left atrial fibrosis was assessed on picrosirius red stained histological sections. Global LA miRNA expression profiling (including the measurement of 800 human miRNA) was carried out using a commercially available kit.

Results

LA mRNA expression of ANP was comparable between the AF-CHF and the SR-CHF groups, suggesting that atrial load occurred to the same level in the two experimental groups. Furthermore, no differences could be observed in the extent of atrial collagen content between the AF-CHF and the SR-CHF groups (collagen area: 20.3±1.3% vs. 23.9±3.1%, n.s.), providing evidence that fibrotic remodelling had occurred to a similar magnitude. The high-throughput miRNA measurement revealed no differences in atrial miRNA expression between the two study groups.

Conclusion

The present study provides evidence for the first time that AF is not associated with different LA miRNA expression in end-stage CHF patients with comparable level of LA dilatation, ANP expression (atrial load) and interstitial fibrosis. Based on these findings, the potential of miRNA-based therapeutic interventions might be limited in AF patients with ischemic end-stage CHF.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): NVKP_16-1-2016-0017

Longitudinal strain reflects the interaction of myocardial contractility to afterload in rat models of hemodynamic overload-induced heart failure

Background

Two-dimensional (2D) speckle tracking echocardiography (STE)-derived myocardial strain parameters are sensitive markers of left ventricular (LV) systolic function. Novel findings suggest that the contractile state of the myocardium, afterload and preload are major determinants of STE measurements. However, the hypothesis that longitudinal strain expresses the interaction between contractility and loading conditions rather than contractility alone in hemodynamic overload-induced heart failure (HF) has not been tested.

Purpose

This study aimed to explore the connection between longitudinal strain and contractility, afterload and preload in rat models of pressure overload (PO)- and volume overload (VO)-induced heart failure (HF).

Methods

Pressure overload (PO)-induced HF was evoked by transverse aortic constriction ([TAC], n=14). Volume overload (VO)-induced HF was established by an aortocaval fistula ([ACF], n=12). Age-matched sham operated animals served as controls. Pressure-volume analysis was carried out to compute cardiac contractility (slope of end-systolic pressure-volume relationship [ESPVR]), afterload (arterial elastance [Ea]) and ventriculo-arterial coupling ([VAC] = Ea/ESPVR). Preload was evaluated by meridional end-diastolic wall stress (σend-diastolic). STE was performed to assess global longitudinal strain (GLS).

Results

GLS was impaired in both PO-induced HF (−5.9±0.6 vs. −12.9±0.5%, TAC vs Sham, P<0.001) and VO-evoked HF (−11.7±0.7 vs. −13.5±0.4%, ACF vs Sham, P=0.048). Hemodynamic measurements indicated that the TAC group presented with maintained ESPVR, increased Ea and enhanced σend-diastolic. In contrast, the ACF group was characterized by reduced ESPVR, decreased Ea and enhanced σend-diastolic. Ordinary least squares non-linear regression revealed that GLS was predominantly determined by afterload (Ea) in the TAC model and by contractility (ESPVR) in the ACF model. In accordance, GLS showed a strong correlation with Ea in case of PO-induced HF (R= 0.848, P<0.001) and with ESPVR in case of VO-evoked HF (R=−0.526; P=0.008), respectively. Furthermore, GLS also demonstrated strong correlation with VAC in both the TAC and the ACF models. Of particular interest, a robust correlation between VAC and GLS could also be detected in the entire study population (R= 0.654, P<0.001).

Conclusion

Both afterload and contractility define GLS. Hence, under conditions when both factors become altered, GLS reflects VAC.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): NVKP_16-1-2016-0017

Characterization of myocardial sodium-glucose cotransporter 1 expression in humans with heart failure and reduced ejection fraction

Introduction

In diabetic patients, multiple cardiovascular outcome trials consistently showed the robust cardioprotective effects of the novel antidiabetic agents, sodium glucose cotransporter 2 (SGLT2) inhibitors. However, the DAPA-HF study using the SGLT2 inhibitor dapagliflozin have extended these observations onto non-diabetic patients with heart failure (HF), urging previous hypotheses regarding the cardioprotective effects of SGLT2 inhibitors to be revised. This is further complicated by the fact that SGLT2 is not expressed in the human myocardium neither under normal nor diseased states. Hence, it has been postulated that SGLT2 inhibitors might exert direct cardioprotection via non-specific inhibition of SGLT1, which is in turn highly expressed in the myocardium.

Purpose

Because literature data is scarce regarding the expression profile of myocardial SGLT1, we aimed to characterize left ventricular SGLT1 expression in humans with end-stage HF accordingly to HF aetiology and to investigate whether cardiac resynchronization therapy (CRT) affects SGLT1 expression.

Methods

From patients undergoing mitral valve replacement with otherwise no myocardial disease and preserved LV function, we collected control papillary muscles (Control, n=9). From patients with end-stage HF undergoing heart transplantation (n=72), we obtained LV anterior wall samples according to the following HF aetiology groups: hypertrophic cardiomyopathy (HCM, n=7); idiopathic dilated cardiomyopathy (DCM, n=12); ischaemic heart disease (IHD, n=14), IHD with type 2 diabetes mellitus (IHD+T2DM, n=11); and patients with CRT (CRT-DCM, n=9; CRT-IHD, n=9; CRT-IHD+T2DM, n=10). We measured LV SGLT1 expression on the gene and protein expression levels using qRT-PCR and western blotting, respectively. Echocardiography-derived LV end-diastolic diameter (LVEDD) and LV ejection fraction (LVEF) were registered prior to surgery.

Results

Compared to controls, LV SGLT1 mRNA and protein expressions were significantly upregulated in patients with DCM, IHD and IHD+T2DM (all P<0.05), but not in HCM. In these patient groups, LV SGLT1 mRNA expression showed a significant positive correlation with LVEDD (r=0.493; P<0.001) and significant negative correlation with LVEF (r=−0.477; P<0.001). On the protein expression level, CRT was associated with significant reduction in LV SGLT1 only in patients with DCM and IHD, but not in IHD+T2DM.

Conclusions

Myocardial SGLT1 is upregulated in patients with HF (except HCM), and correlated strongly with parameters (LVEDD, LVEF) related to adverse LV remodelling. CRT was associated with reduced SGLT1 expression in DCM and IHD patients, but not in those with IHD+T2DM. Our results suggest that SGLT1 is upregulated in HF and might be implicated in adverse myocardial remodelling. Accordingly, whether SGLT2 inhibitors exert direct cardioprotection in HFrEF via non-specific inhibition of SGLT1 needs to be further elucidated.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Research, Development and Innovation Fund of Hungary, Higher Education Institutional Excellence Programme of the Ministry of Human Capacities of Hungary

Cardiac functional consequences of stroke induced by transient middle cerebral artery occlusion in a rodent model

Background

The cardiac functional consequences of ischaemic stroke are still need to be elucidated, while according to ethical issues only non-inasive measurents were carried out in patients underwent transient cerebral ischaemia.

Purpose

We aimed at investigating left ventricular function using non-invasive and invasive modalities in a rat model of transient focal ischaemia.

Methods

Age-matched, young adult rats were used for this study. Serial left ventricular echocardiographic measurements and speckle-tracking analysis were performed in rats (n=9) underwent transient middle cerebral artery occlusion (MCAO) before, during and immediately after the induction of stroke, with a follow-up at 24, 48, 72 hours; 7, 11 and 14 days. In another experimental setting, 48 hours after stroke induction (MCAO group, n=9) we characterized left ventricular function by pressure-volume analysis, that was compared to sham-operated controls (Co group, n=9).

Results

Serial echocardiographic measurements showed impaired systolic function, that was most severe 48 hours after MCAO (global circumferential strain, GCS: −14.8±2.6% 48 hours after MCAO vs. −19.3±2.4% baseline, p<0.05). A complete recovery of systolic functional deterioration was observed after 14 days (GCS: −19.2±2.5% 14 days after MCAO vs. −19.3±2.4% baseline, n.s.). Heart weight (normalized to tibial weight) did not differ between MCAO and Co animals. Pressure-volume analysis revealed unaltered diastolic function and showed unchanged load-independent contractility index values (slope of end-systolic pressure-volume relationship, ESPVR: 2.56±0.29mmHg/μl MCAO vs. 2.55±0.59 mmHg/μl Co, n.s.) after MCAO. There was a tendency towards increased systolic pressure and deteriorated ventriculo-arterial coupling in animals underwent stroke.

Conclusions

Our data suggests that MCAO is associated with reversible impairment of systolic function during echocardiographic measurements, however without alteration of intrinsic myocardial contractility. The tendency towards increased afterload might explain the observed alterations in rats underwent stroke.

Funding Acknowledgement

Type of funding source: None

Sex-related differences in cardiac and myofilament function in rats with pressure-overload induced left ventricular hypertrophy

Introduction

Recent findings indicate that sex is a major determinant of left ventricular (LV) structure in pressure overload (PO)-induced LV myocardial hypertrophy (LVH). However, data are scare regarding sex-related differences in LV function in case of PO-evoked LVH.

Aim

Hence, in the present study we aimed at comprehensively investigating sex-related functional differences on the global cardiac level and also on the myofilament level in PO-induced LVH.

Method

Abdominal aortic banding (AB) was carried out to induce chronic PO for 6 or 12 weeks in male and female rats. Age- and sex-matched sham-operated animals served as controls. The development of LVH was followed by serial echocardiography. The extent of cardiomyocyte hypertrophy and myocardial fibrosis were evaluated by histology. Cardiac function was assessed by pressure-volume analysis. Force measurement was carried out in permeabilized cardiomyocytes to compute myofilament function.

Results

At week 6, robust myocardial hypertrophy, concentric LV geometry and moderate interstitial fibrosis were detected in both male and female AB rats. This early stage of PO-induced LVH was associated with increased LV contractility (slope of end-systolic pressure-volume relationship [ESPVR, mmHg/μl]: 3.09±0.18 Male-AB-wk6 vs. 1.79±0.22 Male-Sham-wk6 P<0.05; 3.68±0.77 Female-AB-wk6 vs. 1.87±0.21 Female-Sham-wk6 P<0.05) and enhanced myofilament Ca2+ sensitivity in both sexes (pCa50: 5.86±0.01 Male-AB-wk6 vs. 5.73±0.02 Male-Sham-wk6 P<0.05; 5.94±0.03 Female-AB-wk6 vs. 5.73±0.01 Female-Sham-wk6 P<0.05). At week 6, the augmented LV contractility effectively counterbalanced the increased afterload in both male and female AB groups. Hence, ventricular-arterial coupling (VAC) was maintained and LV systolic function was preserved in the AB groups in both sexes. In contrast, at week 12, marked sex differences could be observed. At this later stage, LVH was characterized by eccentric remodeling and intensified collagen accumulation in male AB rats. The initial LV contractility augmentation (slope of ESPVR, mmHg/μl: 1.74±0.13 Male-AB-wk12 vs. 1.31±0.17 Male-Sham-wk12 n.s.) as well as the enhanced myofilament Ca2+ sensitivity (pCa50: 5.78±0.02 Male-AB-wk12 vs. 5.75±0.01 Male-Sham-wk12 n.s.) diminished, leading to impaired VAC and reduced LV systolic function. On the contrary, in female AB rats, cardiac contractility (ESPVR, mmHg/ μl: 3.97±0.50 Female-AB-wk12 vs. 2.08±0.17 Female-Sham-wk12 P<0.05) and myofilament Ca2+ sensitivity (pCa50:5.85±0.02 Female-AB-wk12 vs. 5.78±0.01 Female-Sham-wk12 P<0.05) remained increased, resulting in adequate VAC and preserved LV systolic function at late-stage of PO-induced LVH as well.

Conclusion

The initially augmented LV contractility and enhanced myofilament Ca2+ sensitivity declines in male but not in female AB rats at later time points. Hence, characteristically different alterations occur in LV systolic function between the two sexes in late-stage of PO-evoked LVH.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): NVKP_16-1-2016-0017.

Evaluation of cardiac titin expression after long-term exercise in a rat model

Introduction

The main role of the giant elastic protein titin is to provide passive stiffness to striated (i.e. cardiac and skeletal) muscles. The adult cardiac muscle contains two titin isoforms: the more compliant N2BA and the stiffer N2B isoforms. Titin reduces passive stiffness in cardiac muscle by increased expression of the more compliant N2BA isoform (elevated N2BA:N2B ratio). Moreover, decreased passive stiffness is associated with increased exercise tolerance. Long-term exercise induces physiological adaptation of the heart, termed athlete's heart. Currently, there is limited data of titin's role in the athlete's heart.

Aims

Our aim is to evaluate exercise-induced morphological and functional changes of the heart. Furthermore, to determine the N2BA:N2B ratio in the rat model of athlete's heart.

Methods

Rats were divided into exercised (n=12) and control (n=12) groups. Athlete's heart was induced by a 12-week-long swim training (200min/day). The control group swam 5 min/day. Following the training period cardiac changes were assessed by echocardiography. In vivo cardiac function was examined by left ventricular (LV) pressure-volume (P-V) analysis. Titin isoform expressions were detected by sodium-dodecyl-sulfate (SDS)-agarose gel electrophoresis.

Results

Echocardiography and post-mortem measured cardiomyocyte diameters confirmed athlete's heart and LV hypertrophy in exercised rats. P-V analysis showed improved contractility, active relaxation and mechanoenergetics in the exercised group. The N2BA:N2B titin ratio was significantly increased in exercised rats compared to controls (0.28 vs. 0.21, p<0.05).

Conclusions

Our results confirm the morphological and functional changes of the athlete's heart. The increased ratio of N2BA:N2B titin corresponds to a more compliant heart in the exercised rats.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): National Research, Development and Innovation Office of Hungary (K 120277) and the ÚNKP-19-3-I New National Excellence Program of The Ministry For Innovation and Technology.

Effect of cardiac resynchronization therapy on left ventricular fibrosis-related mRNA expression profile in patients with end-stage heart failure

Background

When indicated, cardiac resynchronization therapy (biventricular pacing, CRT) decreases mortality in patients with heart failure (HF) and reduced ejection fraction, especially in those with non-ischemic cardiomyopathy. This is reflected by relatively rapid improvement of left ventricular (LV) end-diastolic diameter (LVEDD) and LV ejection fraction (LVEF) indicating reverse remodelling. These LV structural and functional improvements are accompanied by characteristic changes in LV gene expression profile. However, whether beneficial gene expression alterations related to biventricular pacing are sustained independently of structural and functional reverse remodelling is unclear.

Purpose

We aimed to compare LV fibrosis-related mRNA expression profile in end-stage HF patients with idiopathic dilated cardiomyopathy (DCM) who were not on CRT versus to those on CRT.

Methods

Left ventricular myocardial samples were harvested from end-stage HF patients undergoing heart transplantation (HTX). Inclusion criteria were negative family history of DCM, negative coronarography (i.e. non-ischemic), no relevant comorbidity (e.g. diabetes, hypertension) and no history of myocarditis. Accordingly, the following patient groups were included: 1.) DCM (n=12, 17% female, mean age [±standard deviation] 46.8±11.8 years) without CRT and 2.) CRT-DCM (n=12, 42% female, mean age 47.8±12.3 years) which comprised DCM patients on active CRT for mean 3.2±2.4 years until HTX. LV RNA was extracted and subjected to a commercially available mRNA expression panel interrogating 760 genes related to the development and regulation of fibrosis. Normalization to 10 housekeeping genes and batch corrections were conducted as per protocol. LV mRNA expression of atrial-natriuretic peptide (ANP) was quantified using qRT-PCR.

Results

Markers of reverse remodelling including LVEDD (73.4±8.3 mm vs 75.4±9.9 mm), LVEF (21.9±3.7% vs 18.5±6.8%) and LV ANP mRNA expression (arbitrary units: 1.05±1.80 vs 1.04±0.88) were comparable between DCM and CRT-DCM patients (all P>0.05), respectively. High-throughput mRNA expression screening revealed significant (all P<0.001) downregulation of 3 genes proven to be implicated in adverse LV remodelling: alpha catalytic subunit of protein phosphatase 2 (PPP2CA), interleukin 20 receptor subunit beta (IL20RB) and lipoprotein lipase (LPL). According to pathway analysis using directed significance scores, CRT was associated with collective upregulation of genes modifying complement activation (SERPING1, C1S, CFH) and collective downregulation of genes promoting cell proliferation (PPP2CA, ANAPC7, HSP90AA1, CSNK2B).

Conclusions

Independently of structural and functional reverse remodelling, CRT might be associated with slightly favourable LV expression profile of genes related to the regulation and development of fibrosis. This suggests that biventricular pacing might be beneficial on the molecular level beyond improvement of LV structure and function.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Research, Development and Innovation Fund of Hungary, Higher Education Institutional Excellence Programme of the Ministry of Human Capacities of Hungary

Perineal hernia mesh repair: a fixation with glue, sutures and tacks. How to do it

Introduction: Many different approaches for the repair of a perineal hernia (PH) after abdomino-perineal rectum amputation (APR) have been described throughout the years. Literature shows us that the use of a mesh had the best results with relatively low rates of recurrence compared to primary suture. Yet there is still no consensus on the best technique for fixation of the mesh in the perineal cavity. Methods: We want to introduce an addition to the surgical repair technique, using laparoscopic glue to ensure a solid fixation of the mesh. This is to prevent small bowel from sliding into the perineal area due to the high abdominal pressure when standing and to avoid the difficulties and risks of laparoscopical suturing in this area. Results: This use of glue for fixation of the mesh has been successful in the three cases described, with no recurrence after one-year follow-up. Conclusion: A recurrent PH can be prevented by a solid fixation of the mesh using the technique of a glued mesh repair. This technique shows to be easy, fast and without recurrence.

Cardiovascular death and progression to end-stage renal disease after major surgery in elderly patients

BACKGROUND

Reliable estimates for risk of cardiovascular-specific mortality and progression to end-stage renal disease (ESRD) among elderly patients undergoing major surgery are not available. This study aimed to develop simple risk scores to predict these events.

METHODS

In a single-centre cohort of elderly patients undergoing major surgery requiring hospital stay longer than 24 h, progression to ESRD and long-term cardiovascular-specific mortality were modelled using multivariable subdistribution hazard models, adjusting for co-morbidity, frailty and type of surgery.

RESULTS

Before surgery, 2·9 and 11·9 per cent of 16 655 patients had ESRD and chronic kidney disease (CKD) respectively. During the hospital stay, 46·9 per cent of patients developed acute kidney injury (AKI). Patients with kidney disease had a significantly higher risk of cardiovascular-specific (CV) mortality compared with patients without kidney disease (adjusted hazard ratio (HR) for CKD without AKI 1·60, 95 per cent c.i. 1·25 to 2·01; AKI without CKD 1·70, 1·52 to 1·87; AKI with CKD 2·80, 2·50 to 3·20; ESRD 5·21, 4·32 to 6·27), as well as increased progression to ESRD (AKI without CKD 5·40, 3·44 to 8·35; CKD without AKI 8·80, 4·60 to 17·00; AKI with CKD 31·60, 19·90 to 49·90). CV Death and ESRD Risk scores were developed to predict CV mortality and progression to ESRD. Calculated CV Death and ESRD Risk scores performed well with c-statistics: 0·77 (95 per cent c.i. 0·76 to 0·78) and 0·82 (0·78 to 0·86) respectively at 1 year.

CONCLUSION

Kidney disease in elderly patients undergoing major surgery is associated with a high risk of CV mortality and progression to ESRD. Risk scores can augment the shared decision-making process of informed consent and identify patients requiring postoperative renal-protective strategies.

P4424Detailed characterization of atrial remodeling induced by exercise training in a rodent model of exercise-induced cardiac hypertrophy

Introduction

Atrial fibrillation and heart failure share common risk factors and frequently coexist as atrial fibrillation leads to impaired myocardial function. Although regular exercise training is associated with cardiovascular benefits, the increased risk of atrial arrhythmias has been observed, with differences regarding prevalence between genders. While multiple mechanisms are likely, the atrial alterations induced by long-term physical exercise still need to be elucidated.

Purpose

We aimed at investigating exercise-induced atrial remodeling in a rat model of athlete's heart and determining sex-specific differences.

Methods

Age-matched young adult rats were divided into female exercised (FEx), female control (FCo), male exercised (MEx) and male control (MCo) groups. After exercised animals completed a 12-week-long swim training protocol, echocardiography was used to describe atrial alterations. In vivo electrophysiologic investigation was performed by programmed stimulation with an octapolar catheter inserted into the right atrium and atrial gene expression analysis was carried out.

Results

Post-mortem atrial weight data revealed marked atrial hypertrophy (atrial weight to tibial length: 18.6±2.7g/cm FEx, 10.3±1.0g/cm FCo, 23.7±2.2g/cm MEx, 15.8±1.9g/cm MCo pex<0.01), while echocardiography data showed slight atrial dilatation and improved contraction in both exercised groups. Exercise training was associated with bradycardia, P-wave enlargement and prolonged right atrial effective refractory period (RAERP: 45.7±4.3ms FEx, 40.2±5.9ms, FCo, 49.8±4.2ms MEx, 43.1±4.6ms MCo pex<0.01). Sinus node recovery time (SNRT) did not differ between groups and we could not induce significant number of arrhytmias by programmed stimulation (double extrastimulation, burst pacing) in any groups. We found increased atrial gene expression of antioxidant enzymes (e.g. NADPH oxidase 2, superoxide dismutase 2) in both genders. Despite the marked atrial hypertrophy, no gene expression alteration was found regarding markers that describe pathological remodeling (atrial natriuretic factor), proinflammatoric (tumor necrosis factor-α) and profibrotic [e.g. transforming growth factor-β (TGF-β), matrix metalloproteinase-2 (MMP-2)] processes. While exercise training did not affect on the expression of profibrotic markers, female gender was associated with lower TGF-β and MMP-2 expression. We found altered expression of ion channels participating in atrial depolarization and repolarization.

Conclusions

Our data suggests that long-term exercise-induced atrial hypertrophy is not associated with harmful electrical remodeling and no inflammatory or profibrotic response was observed in the atrium of exercised rats.

Acknowledgement/Funding

NKFIH (K 120277), ÚNKP-17-4 (to A.O.), STIA-KF-17 (to A.O.)

P3454Myocardial reverse remodeling occurs to a comparable extent in male and female aortic-banded rats following pressure unloading

Background

Sex differences have been intensely investigated during the development of pressure overload (PO; e.g. aortic stenosis, arterial hypertension)-induced left ventricular (LV) myocardial hypertrophy (LVH). However, it is less clear whether sex-related differences also affect the regression of pathological LVH after pressure unloading.

Purpose

Therefore, we investigated the potential influential effect of sex on myocardial reverse remodeling in a relevant rat model of banding and debanding of the abdominal aorta.

Methods

PO of the left ventricle was induced in male (M) and female (F) rats by abdominal aortic banding (AB) for 6 or 12 weeks. Sham operated animals served as controls. Pressure unloading was evoked by removing the aortic constriction at week 6 (debanded). Serial echocardiography was performed to detect temporal alterations in LV morphology and geometry. Furthermore, distinct aspects of LV systolic and diastolic function were assessed by pressure-volume analysis. Structural changes, such as cardiomyocyte hypertrophy and interstitial fibrosis were measured on histological sections. Fetal gene expression (a molecular marker of pathological LVH) was analyzed by quantitative real-time PCR.

Results

In both male and female AB rats, PO induced the development of marked LVH as confirmed by increased LV mass, heart weight-to-tibial length ratio (HW/TL [g/cm]: 0.47±0.01 AB-M vs. 0.36±0.01 Sham-M, p<0.05; 0.36±0.02 AB-F vs. 0.26±0.01 Sham-F, p<0.05) and cardiomyocyte diameter. Similarly, reactivation of fetal gene expression (indicated by increased atrial natriuretic peptide [ANP]) and enhanced interstitial collagen accumulation was also observed in male and female AB groups as well. The extent of myocardial hypertrophy was greater among female AB animals, while fibrosis was more severe in male AB rats. In both genders, LVH was associated with prolonged ventricular relaxation (active relaxation time constant, Tau [ms]: 19.6±0.8 AB-M vs. 13.1±0.4 Sham-M, p<0.05; 15.2±1.3 AB-F vs. 12.2±0.3 Sham-F, p<0.05). However, systolic function was impaired only in males (ejection fraction, [%]: 44.4±2.3 AB-M vs. 57.5±2.1 Sham-M, p<0.05; 49.7±2.2 AB-F vs. 53.4±1.7 Sham-F, n.s.). Contrary to the sex-dependent differences during the development of LVH, removing the aortic constriction resulted in a comparable degree of reverse remodeling on the morphological (decreased LV mass, HW/TL), histological (decreased CD and interstitial fibrosis), molecular (reduced ANP expression) and functional (recovered ejection fraction and Tau) levels in both male and female rats.

Conclusion

Pressure unloading at a relatively early time point leads to myocardial reverse remodeling to a comparable degree in male and female rats.

Acknowledgement/Funding

NVKP-16-1-2016-0017; ÚNKP-18-3-I-SE-9

Radiological outcome after treatment of juvenile flatfeet with subtalar arthroereisis: a matched pair analysis of 38 cases comparing neurogenic and non-neurogenic patients

PURPOSE

Therapy of juvenile neurogenic flatfoot (JNF) with subtalar arthroereisis (SA) is currently under critical clinical investigation. In this retrospective matched pair analysis, the radiological outcome after arthroereisis in paediatric patients with infantile cerebral palsy and JNF was compared with children with juvenile flatfeet (JF) without neurological diseases.

METHODS

From October 2007 to April 2018 80 patients with 149 flatfeet underwent surgery with SA. Inclusion criteria were: 1) JNF or JF with age at surgery ≤ 13 years; 2) treatment with SA; 3) presence of three sets of biplane radiographs (preoperative, postoperative and follow-up (FU)). The radiographs were analyzed for: 1) navicular-cuboidal-index (NCI); 2) talocalcaneal angle anteroposterior; 3) talocalcaneal angle lateral; 4) calcaneal-pitch (CP); and 5) talometatarsal-index (TMTI). Following this, 25 patients with 38 flatfeet could be included.

RESULTS

The mean age at SA of the JNF group was 9.2 years (JF group: 9.3 years) and the mean time of FU was 35.2 months (JF group: 39.4 months). In comparison with preoperatively, a significant decrease of the NCI was seen in both groups (p = ≤ 0.05 and p = ≤ 0.001) in the FU radiographs. The analysis of CP and TMTI in the JF group also resulted in a significant improvement (p = ≤ 0.001 and p = ≤ 0.05). Overall, the comparison between the JNF and JF group showed no significant differences in regard to the analyzed postoperative parameters.

CONCLUSION

Based on this data, treatment of flatfeet by SA in patient with neurological disorders shows an improvement of radiological parameters comparable with neurologically unimpaired patients and might be considered as additional treatment option.

LEVEL OF EVIDENCE

IV.