"How did you stay together so long?" Relationship longevity, a cross-generational qualitative study

This global qualitative study adopted a cross-generational approach considering key factors contributing to relationship longevity. Relatively few studies consider factors leading to relationship longevity as articulated by couples themselves, and there is a paucity of research considering young couples' questions regarding relationship longevity. This study has two sample groups. In sample one (n = 137) we asked individuals in relationship of 3-15 years questions they would ask couples in marriages of 40+ years. We then asked our second sample of coupled individuals married 40+ years (n = 180) these questions. The primary question from the younger couples to couples in long-term marriages regarded their "secret" to relationship longevity. This study focuses on this one question and coupled individuals' self-articulation of their "secrets" to relationship longevity. The top seven were (1) commitment, (2) altruism, (3) shared values, (4) good communication, (5) compromise: give and take, (6) love, and (7) never give up. The clinical implications for couple therapists are discussed.

Left Atrial Appendage Occlusion on a Beating Heart during Minimally Invasive Valve Surgery Using an Aortic Endoclamp: A Case Report

Concomitant LAA occlusion has been shown to be an effective and safe treatment for patients with atrial fibrillation during cardiac surgery to prevent embolic stroke. Minimally invasive procedures are challenging due to restricted access to and visibility of the surgical site. Also, aortic endoclamping has been developed as an alternative surgical approach to exoclamping. The aim of this article is to demonstrate the method of beating heart LAA occlusion with the Atriclip® (AtriCure, Mason, OH, USA) device during minimally invasive mitral valve surgery while using the endoclamping alternative for aortic cross-clamping.

A Dual-Pathogen Mitral Valve Endocarditis Caused by Coxiella burnetii and Streptococcus gordonii-Which Came First?

Infective endocarditis (IE) is still a life-threatening disease with high morbidity and mortality. While usually caused by a single bacterium, poly-microbial infective endocarditis (IE) is rare. Here, we report a (blood-culture-negative) dual pathogen mitral valve IE caused by Coxiella burnetii and Streptococcus gordonii: A 53-year-old woman was presented to an internal medicine department with abdominal pain for further evaluation. Within the diagnostic work up, transthoracic echocardiography (TTE) revealed an irregularly shaped echogenic mass (5 × 13 mm) adherent to the edge of the posterior mitral valve leaflet and protruding into the left atrium. As infected endocarditis was suspected, blood cultures were initially obtained, but they remained negative. Chronic Q fever infection was diagnosed using serologic testing. After the occurrence of cerebral thromboembolic events, the patient was admitted for mitral valve surgery. Intraoperatively, a massively destructed mitral valve with adhering vegetations was noted. Examination of the mitral valve by broad-range bacterial polymerase chain reaction (PCR) and amplicon sequencing confirmed Coxiella burnetii infection and yielded Streptococcus gordonii as the second pathogen. Based on the detailed diagnosis, appropriate antibiotic therapy of both pathogens was initiated, and the patient could be discharged uneventfully on the 11th postoperative day after a successful minimal-invasive mitral valve replacement.

Patient-tailored silicone plug for HeartMate 3™ left ventricular assist device explantation

Patient-tailored silicone plug for HeartMate 3™ left ventricular assist device explantation in two successive males proceeded successfully. Given medical therapeutic advancements, FDA-approved plug systems designed by LVAD manufacturers themselves will be necessary for the near future to provide a safe and simple device explantation alternative that fulfills all regulatory standards.

Intraoperative visualization of a deformed left main stent during surgical aortic valve replacement

BACKGROUND

While coronary artery bypass grafting is typically considered first choice for the treatment of left main stenosis, there is a trend towards left main stenting due to a steadily aging population in western countries with a high operative risk and patients with single vessel coronary artery disease affecting the left main artery. Nevertheless left main stenting remains controversial, especially in patients with concomitant indications for open-heart surgery.

CASE PRESENTATION

We want to present a case of a 78-year-old male patient with high-grade aortic stenosis who underwent surgical aortic valve replacement at our heart center due to anatomical contraindications for transcatheter aortic valve replacement. Stenting of the left main coronary artery was performed three years earlier due to single vessel coronary artery disease while moderate aortic valve stenosis was under surveillance at the time of the intervention. Intraoperatively we found the stent to be deformed inside the left main coronary artery, covering nearly 25% of the coronary ostium. So injection of cardioplegia directly into this ostium, as we perform normally, was not possible without further damaging the stent and/or the opening of the ostium. We had to insert cardioplegia via the retrograde way, so via the coronary sinus.

CONCLUSION

While left main stenting can be reasonable for a specific population of patients, it should be used cautiously in patients with concomitant indications for open-heart surgery in the near future and a low perioperative risk profile.

Double valve replacement in a case of Hedinger syndrome

Hedinger Syndrome or carcinoid heart disease is a rare cardiac complication of neuroendocrine tumors (NET) affecting the tricuspid and pulmonary valves. Following is a case description of a patient undergoing treatment for a neuroendocrine tumor with liver metastasis, referred with symptomatic tricuspid valve regurgitation and pulmonary valve stenosis for surgical valve replacement. Planned surgical valve replacement was successfully performed before the onset of severe right ventricular failure or pulmonary hypertension in this case of carcinoid heart disease. An interdisciplinary approach and regular follow up is recommended in such cases.

Corrigendum: long-term cultivation of human atrial myocardium

[This corrects the article DOI: 10.3389/fphys.2022.839139.].

Recovery of a dilated left ventricle after cessation of cocaine and HVAD™ explantation using a titanium plug

The ultimate goal in the treatment of end-stage heart failure is the recovery of cardiac function following mechanical assistance of the left ventricle. The HVAD™ pump (HeartWare Inc.) left ventricular assist device (LVAD) can be explanted without resternotomy. This article demonstrates that the use of a custom-made mechanical plug (manufactured by INNOVO Solutions GmbH), which can be inserted into the LVAD's sewing ring, is feasible. This mechanical plug explicitly designed for device explantation is a viable alternative to the current standard of care. This article adopts a less invasive technique to explant the pump. The following case illustrates this technique.

Retrograde washout of prepump LVAD thrombosis in a patient on HeartWare™ support

The success of the left ventricular assist device (LVAD) as a treatment for terminal left-side heart failure is still restrained by some severe complications associated with mechanical circulatory support. Pump thrombus still affects many patients. It is associated with high morbidity and mortality. The therapeutic options include augmentation of anticoagulation and antiplatelet medication, intravenous or catheter-guided thrombolysis, and pump exchange. Heart transplantation would be a desirable option in this population, but unfortunately, it is only theoretical given the increasing number of LVAD implants and decreasing number of organ donors. A retrograde washout maneuver may be a treatment option in prepump thrombosis in selected patients. Therefore, the decision should be made on an individual basis after balancing the risks and benefits of different treatment approaches. In this context, we report a case of retrograde washout of prepump thrombus in a patient who has been on HeartWare™ support for more than 3 years, with a successful bailout strategy.

Direct Impact of Human Platelets on the Development of Transplant Arteriosclerosis

BACKGROUND

Platelets play an important role in the pathogenesis of inflammatory and proliferative vascular changes. The aim of this study was to investigate whether human platelets are able to induce transplant arteriosclerosis in a humanized C57/Bl6-Rag2-/-γc-/- mouse xenograft model.

METHODS

Nonactivated and in vitro-activated human platelets were analyzed and phenotyped for surface markers by flow cytometry. Side branches of human mammary arteries were implanted into the infrarenal aorta of recipients, followed by daily application of human platelets and histological analyzed on day 30 after transplantation.

RESULTS

Human platelets collected by apheresis had low levels of platelet activation markers. However, after in vitro activation, expression was markedly increased. Sixty minutes after injection in recipient mice, nonactivated human platelets become significantly activated. Increased adhesion of platelets to the vascular endothelium was detected by in vivo fluorescence microscopy. After intravenous injection of nonactivated or activated platelets, human xenografts showed pronounced intimal proliferation. Immunohistological analysis showed that the group treated with activated human platelets exhibited significantly increased intragraft protein expression of intracellular adhesion molecule-1 and platelet-derived growth factor receptor beta and smooth muscle cell migration into the neointima.

CONCLUSIONS

These data demonstrate that an isolated daily application of both in vivo- and in vitro-activated human platelets results in the development of transplant arteriosclerosis in a humanized mouse transplantation model.

AB0295 HIGHER PREVALENCE OF DEPRESSION WITH LINK TO CHILDHOOD TRAUMA IN AN EARLY ARTHRITIS COHORT – A SELECTIVE DATA ANALYSIS (PSYRA-STUDY)

Background

In patients with arthritis, psychological co-morbidities are very common. Previous studies have found a relatively high prevalence of depression, anxiety, and post-traumatic stress disorder (PTSD), especially in long-term disease. Recent research has begun to study psychiatric co-morbidities not just as an outcome, but also as a probable risk factor, evaluating patients in the early disease stages. [1] Furthermore, some sources suggest that childhood adversities could impact the autoimmune process in adulthood. [2]

Objectives

To compare the prevalence of depression, anxiety, PTSD, and childhood trauma in a prospective early arthritis cohort to a healthy age- and gender-matched control group. Moreover, to explore whether these factors may contribute to the early arthritis development.

Methods

This selective data analysis of prospective single-centre, observational study included 60 patients with an early arthritis and 60 healthy controls. The control group was defined as no inflammatory joint pain and further subdivided into 2 subgroups, differentiating 24 patients with arthralgia and 36 with no arthralgia and not from the outpatient consultation. Early arthritis was defined as the presence of at least one inflammatory joint from 4 weeks to 12 months, independent of rheumatic diagnosis. For the assessment of current and prior psychological co-morbidities, included patients underwent semi-structured interview and received the standardized questionnaires for depression/anxiety (Hospital Anxiety and Depression Scale (HADS)), childhood trauma (Childhood Trauma Questionnaire (CTQ)) and PTSD (Posttraumatic Diagnostic Scale (PDS)) respectively. Differences among the groups were analyzed with Chi Square and Mann-Whitney U tests. A backwards binominal logistic regression model in reference to the healthy patients was performed to identify the significant factors for the early arthritis group.

Results

The mean age of the total group was 47.4 ± 16.0 (♀ 58.3%, mean symptom duration 4.5±3.3 months). Depression rate of 41.7% according to interview was significantly higher in early arthritis group compared to 16.7% in healthy patients (p=0.03). Regarding arthralgia subgroup, depression was also high with 34%. HADS-D score was also significantly higher in early arthritis (5.4±4.8) to healthy cohort (3.6±3.3) (p=0.047). Compared to 3.3% in healthy patients, PTSD rate of 13.3% was also significantly higher in the arthritis group (p=0.048). We could not detect a significant difference between these two groups using the U test while evaluating CTQ dimensions. We performed a subsequent subgroup analysis and found that childhood trauma dimensions were relevant in arthralgia group, as 25% presented with high emotional abuse score. The logistic regression model showed that emotional neglect, sexual abuses in childhood as well as HADS-D were significant covariates for early arthritis. (p=0,048 OR=1.2; p=0.040 OR=1.4, p=0.025 OR=1.2 respectively).

Conclusion

As the rates of depression and PTSD, as well as HADS-D score were significantly higher in the early arthritis cohort compared to healthy individuals, our findings suggest a potential link between psychiatric outcomes and inflammation. According to our regression model certain childhood adversities and depression are significant factors for an early arthritis group. Arthralgia group had similar aberrant scores regarding childhood trauma, implying that early-life stress might be an important factor in understanding this condition.

References

[1]Vallerand IA et al. Depression as a risk factor for the development of rheumatoid arthritis: a population-based cohort study. RMD Open.2018; 4(2)

[2]Dube SR et al. Cumulative childhood stress and autoimmune diseases in adults. Psychosom Med. 2009; 71(2):p.243-50.

Disclosure of Interests

None declared

Long-Term Cultivation of Human Atrial Myocardium

Organotypic culture of human ventricular myocardium is emerging in basic and translational cardiac research. However, few institutions have access to human ventricular tissue, whereas atrial tissue is more commonly available and important for studying atrial physiology. This study presents a method for long-term cultivation of beating human atrial myocardium. After written informed consent, tissues from the right-atrial appendage were obtained from patients with sinus rhythm undergoing open heart surgery with cardiopulmonary bypass. Trabeculae (pectinate muscles) prepared from the samples were installed into cultivation chambers at 37°C with a diastolic preload of 500 μN. After 2 days with 0.5 Hz pacing, stimulation frequency was set to 1 Hz. Contractile force was monitored continuously. Beta-adrenergic response, refractory period (RP) and maximum captured frequency (f_max) were assessed periodically. After cultivation, viability and electromechanical function were investigated, as well as the expression of several genes important for intracellular Ca²⁺ cycling and electrophysiology. Tissue microstructure was analyzed by confocal microscopy. We cultivated 19 constantly beating trabeculae from 8 patient samples for 12 days and 4 trabeculae from 3 specimen for 21 days. Functional parameters were compared directly after installation (0 d) with those after 12 d in culture. Contraction force was 384 ± 69 μN at 0 d and 255 ± 90 μN at 12 d (p = 0.8, n = 22), RP 480 ± 97 ms and 408 ± 78 ms (p = 0.3, n = 9), f_max 3.0 ± 0.5 Hz and 3.8 ± 0.5 Hz (p = 0.18, n = 9), respectively. Application of 100 nM isoprenaline to 11 trabeculae at 7 d increased contraction force from 168 ± 35 μN to 361 ± 60 μN (p < 0.01), f_max from 6.4 ± 0.6 Hz to 8.5 ± 0.4 Hz (p < 0.01) and lowered RP from 319 ± 22 ms to 223 ± 15 ms. CACNA1c (L-type Ca²⁺ channel subunit) and GJA1 (connexin-43) mRNA expressions were not significantly altered at 12 d vs 0 d, while ATP2A (SERCA) and KCNJ4 (Kir2.3) were downregulated, and KCNJ2 (Kir2.1) was upregulated. Simultaneous Ca²⁺ imaging and force recording showed preserved excitation-contraction coupling in cultivated trabeculae. Confocal microscopy indicated preserved cardiomyocyte structure, unaltered amounts of extracellular matrix and gap junctions. MTT assays confirmed viability at 12 d. We established a workflow that allows for stable cultivation and functional analysis of beating human atrial myocardium for up to 3 weeks. This method may lead to novel insights into the physiology and pathophysiology of human atrial myocardium.

Prolapsing Left Atrial Mass Presenting as Syncope

Background  Myxomas are the most common primary cardiac tumor in adults and are most commonly found within the left atrium. These are usually asymptomatic, detected incidentally, or present gradually with symptoms typical of heart failure.

Case Description  This case report is a description of a case of syncope caused by a large left atrial myxoma.

Conclusion  Atrial myxomas may present with transient loss of consciousness, especially when they prolapse through the atrioventricular valves or when embolization occurs. Non-invasive diagnostic tools (e.g., echocardiogram, cardiac computed tomography) should be considered to thoroughly evaluate cardiogenic causes of syncope.

Mitral Multifocal Papillary Fibroelastoma in a Patient with Aggressive Fibromatosis

Mitral valve fibroelastoma is a rare condition that can be associated with high morbidity rates due to thrombus formation and resulting embolic events. Causative treatment for affected patients is mitral valve surgery. An association between cardiac fibroelastoma and desmoid-type fibromatosis, an aggressive form of fibromatosis, is not yet described. We present a case of a 58-year-old man with a history of desmoid-type fibromatosis and concomitant papillary fibroelastoma of the mitral valve who consequently underwent mitral valve replacement.

Pass On What You Have Learned: A Structured Mentor-Mentee Concept for the Implementation of a Minimally Invasive Mitral Valve Surgery Program

INTRODUCTION

Starting a minimally invasive cardiac surgery (MICS) for mitral valve repair (MVR) program is challenging as it requires a new learning curve, but compromising surgical results at the same time is not acceptable. Here, we describe our surgical educational experience of starting a new MICS program at a university heart center in Germany.

METHODS

A dedicated team for the new MICS program including 2 cardiac surgeons, 1 cardiac anesthetist, 1 perfusionist, and 1 scrub nurse was chosen. The use of long shafted instruments was trained in a low-cost self-assembled MICS simulator, and the EACTS endoscopic dry lab course was visited. Thereafter, 1 MICS center was visited for direct observation and peer-to-peer education for 6 weeks. The mentor observed the first 10 cases performed by the mentee. The surgical mitral valve expertise of 1 single cardiac surgeon was retrospectively analyzed between April 2016 and April 2021.

RESULTS

Before the implementation of the MICS-MVR program, 18 mitral valve operations have been performed through sternotomy between April 2016 and October 2018 including 12 replacements and 6 ring annuloplasties. After starting the MICS-MVR program, 73 mitral operations have been performed by the same surgeon of which 53 video-assisted through minithoracotomy (72.6%). 83.1% of the MICS procedures included complex repair (n = 38) and ring annuloplasty (n = 6). Open heart MV surgery was necessary in 20 patients due to concomitant procedures (n = 8), redo procedures (n = 2), severe endocarditis (n = 4), or contraindication for MICS such as PAD (n = 6). There have been no deaths, 1 stroke, and 1 cardiac vascular (RCX) complication. Two patients required conversion to sternotomy and one pericardiocentesis in the long term.

CONCLUSION

Typically, excellent exposure and high repair rates of the MV has led us offer MICS approach to a majority of patients with isolated MV disease. Careful planning and a strict mentor-mentee concept facilitated a safe startup of an MICS program in a busy university heart center.

Role of CMV chemokine receptor M33 in airway graft rejection in a mouse transplant model

BACKGROUND

Cytomegalovirus (CMV) infection is a risk factor for bronchiolitis obliterans (BO), one form of chronic lung allograft dysfunction (CLAD). The viral chemokine receptor M33 is essential for successful spread of murine CMV to host salivary glands. In the present study we investigated the impact of M33 on chronic airway rejection.

METHODS

MHC I-mismatched tracheas of C·B10-H2^b/LilMcdJ mice were transplanted into BALB/c (H2^d) recipients and infected at different dates with wild type (WT) or M33-deleted (delM33) MCMV representing clinical settings of viral recipient (R)-donor (D)-serostatus: (D-/R+) or (D+/R-). Grafts were recovered for gene expression and histological / immunofluorescence analysis, respectively.

RESULTS

Evaluations showed significantly increased signs of chronic rejection in WT-infected mice compared to uninfected allografts seen in lower epithelium/lamina propria-ratio (ELR) (ELR 0.46 ± 0.07 [WT post] vs. ELR 0.66 ± 0.10 [non-inf.]; p < 0.05). The rejection in delM33-infected groups was significantly reduced vs. WT-infected groups (0.67 ± 0.04 [delM33 post]; vs. WT post p < 0.05). Furthermore, decreased rejection was observed in WT pre-infected compared to post-infected groups (0.56 ± 0.08 [WT pre]; vs. WT post p < 0.05). CD8⁺ T cell infiltration was significantly higher in WT-post compared to the delM33 infected or non-infected allografts.

CONCLUSIONS

These data support the role of the CMV in accelerating CLAD. The deletion of chemokine receptor M33 leads to attenuated rejection.

Acute Type A Dissection during Pregnancy with Marfan's Syndrome

Background  Marfan's syndrome (MFS) is a connective tissue disorder, caused by a mutation in the FBN-1 gene and affecting multiple organ systems including the vascular system. During pregnancy, women with MFS have an increased risk of aortic dissection due to changes in the cardiovascular system.

Case Description  We present a 39-year-old woman that suffered from an acute aortic dissection in week 33 of her third pregnancy who urgently required lifesaving surgery. Three-dimensional reconstruction of computed tomography scan was performed with unborn child in utero.

Conclusion  Monitoring of patients with suspected or confirmed MFS appears essential and interdisciplinary treatment and prevention strategies are required.

Microvasculature in murine tracheal allografts after combined therapy with clopidogrel and everolimus

OBJECTIVES

Survival after lung transplantation is mainly limited by the development of chronic lung allograft dysfunction. Previous studies have suggested T-cell mediated proliferation and microvascular changes in experimental small airways models as potential therapeutic targets. The aim of this study was to assess microvascular changes in murine orthotopic tracheal allografts after treatment with everolimus alone or in combination with clopidogrel.

METHODS

C57Bl/6 (H-2b) donor tracheas were orthotopically transplanted into CBA (H-2k) recipients. Mice received daily injections of everolimus (0.05 mg/kg) alone or combined with clopidogrel (1 mg/kg). Twenty-eight days after transplantation, ratio of the thickness of tracheal epithelium and lamina propria was measured as an indicator for chronic rejection. Additionally, graft oxygenation and graft perfusion were detected on postoperative days 4, 10 and 28. Quantitative reverse transcription polymerase chain reaction analysis was used for gene expression analysis.

RESULTS

While syngeneic grafts showed a stable tissue pO2 and undisturbed microvascular perfusion, rejecting allografts had a drastic decline in both parameters as well as a flattened epithelium and an increased thickness of the lamina propria. Treatment with everolimus reduced allogeneic fibroproliferation, but had no protective effects on the microvasculature; polymerase chain reaction analysis indicated hypoxic stress and inflammation. Combining everolimus with clopidogrel improved microvascular integrity in the tracheal grafts, but had no synergistic effect in preventing obliterative bronchiolitis development.

CONCLUSIONS

These data demonstrate that the ability of everolimus to reduce the development of post-transplant obliterative bronchiolitis is not caused by microvascular protection and has no synergistic effects with clopidogrel in acute airway rejection.

Cytomegalovirus chemokine receptor M33 knockout reduces chronic allograft rejection in a murine aortic transplant model

BACKGROUND

Numerous studies suggest that cytomegalovirus (CMV) infection may act as isolated risk factor in the development of cardiac allograft vasculopathy (CAV). Viral G protein-coupled receptors (GPCRs) are thought to contribute to the pathogenic changes associated with CMV infection. The aim of this study was to investigate the role of murine cytomegalovirus GPCR M33 in the development of CAV in a murine aortic allograft model.

METHODS

MHC I-mismatched aortas of C.B10 (H2^b) mice were transplanted into BALB/c (H2^d) recipients, which were either mock-infected, infected with wild type (WT) MCMV or MCMV with a deleted M33-receptor gene (delM33). Persistence of cytomegalovirus infection was confirmed by qPCR and by luciferase assay to ensure active viral replication. Grafts were harvested on days 21 and 37 for intragraft mRNA expression and histological analysis.

RESULTS

Active viral replication was demonstrated and MCMV presence was confirmed by PCR within spleen, liver, salivary glands, lung and the aortic transplant. Infection with delM33 resulted in significantly less intimal proliferation compared to WT-MCMV but more pronounced proliferation than in mock-infected allografts (32.19% [delM33] vs. 41.71% [WT-MCMV] vs. 24.33% [MCMV-]). Intragraft expression of most analyzed genes was significantly increased in infected mice. VCAM-1, ICAM-1, PDGFβ, CXCR3 and Granzyme B were distinctly less expressed in grafts of delM33 infected compared to WT infected mice. Cellular infiltration revealed reduced dendritic cells and T cells in grafts infected with delM33 compared to WT MCMV.

CONCLUSIONS

These data suggest that the MCMV encoded receptor M33 plays an important role as a viral effector mechanism contributing to the development of CAV in a murine aortic transplant model.

COVID-19 among heart transplant recipients in Germany: a multicenter survey

Aims

Heart transplantation may represent a particular risk factor for severe coronavirus infectious disease 2019 (COVID-19) due to chronic immunosuppression and frequent comorbidities. We conducted a nation-wide survey of all heart transplant centers in Germany presenting the clinical characteristics of heart transplant recipients with COVID-19 during the first months of the pandemic in Germany.

Methods and results

A multicenter survey of all heart transplant centers in Germany evaluating the current status of COVID-19 among adult heart transplant recipients was performed. A total of 21 heart transplant patients with COVID-19 was reported to the transplant centers during the first months of the pandemic in Germany. Mean patient age was 58.6 ± 12.3 years and 81.0% were male. Comorbidities included arterial hypertension (71.4%), dyslipidemia (71.4%), diabetes mellitus (33.3%), chronic kidney failure requiring dialysis (28.6%) and chronic-obstructive lung disease/asthma (19.0%). Most patients received an immunosuppressive drug regimen consisting of a calcineurin inhibitor (71.4%), mycophenolate mofetil (85.7%) and steroids (71.4%). Eight of 21 patients (38.1%) displayed a severe course needing invasive mechanical ventilation. Those patients showed a high mortality (87.5%) which was associated with right ventricular dysfunction (62.5% vs. 7.7%; p = 0.014), arrhythmias (50.0% vs. none; p = 0.012), and thromboembolic events (50.0% vs. none; p = 0.012). Elevated high-sensitivity cardiac troponin T- and N-terminal prohormone of brain natriuretic peptide were significantly associated with the severe form of COVID-19 (p = 0.017 and p < 0.001, respectively).

Conclusion

Severe course of COVID-19 was frequent in heart transplanted patients. High mortality was associated with right ventricular dysfunction, arrhythmias, thromboembolic events, and markedly elevated cardiac biomarkers.

The Degree of t-System Remodeling Predicts Negative Force-Frequency Relationship and Prolonged Relaxation Time in Failing Human Myocardium

The normally positive cardiac force-frequency relationship (FFR) becomes flat or negative in chronic heart failure (HF). Here we explored if remodeling of the cardiomyocyte transverse tubular system (t-system) is associated with alterations in FFR and contractile kinetics in failing human myocardium. Left-ventricular myocardial slices from 13 failing human hearts were mounted into a biomimetic culture setup. Maximum twitch force (F), 90% contraction duration (CD₉₀), time to peak force (TTP) and time to relaxation (TTR) were determined at 37°C and 0.2–2 Hz pacing frequency. F_1Hz/F₀._5Hz and F_2Hz/F₀._5Hz served as measures of FFR, intracellular cardiomyocyte t-tubule distance (ΔTT) as measure of t-system remodeling. Protein levels of SERCA2, NCX1, and PLB were quantified by immunoblotting. F_1Hz/F₀._5Hz (R² = 0.82) and F_2Hz/F₀._5Hz (R² = 0.5) correlated negatively with ΔTT, i.e., samples with severe t-system loss exhibited a negative FFR and reduced myocardial wall tension at high pacing rates. PLB levels also predicted F_1Hz/F₀._5Hz, but to a lesser degree (R² = 0.49), whereas NCX1 was not correlated (R² = 0.02). CD₉₀ correlated positively with ΔTT (R² = 0.39) and negatively with SERCA2/PLB (R² = 0.42), indicating that both the t-system and SERCA activity are important for contraction kinetics. Surprisingly, ΔTT was not associated with TTP (R² = 0) but rather with TTR (R² = 0.5). This became even more pronounced when interaction with NCX1 expression was added to the model (R² = 0.79), suggesting that t-system loss impairs myocardial relaxation especially when NCX1 expression is low. The degree of t-system remodeling predicts FFR inversion and contraction slowing in failing human myocardium. Moreover, together with NCX, the t-system may be important for myocardial relaxation.

Platelets and Immune Responses During Thromboinflammation

Besides mediating hemostatic functions, platelets are increasingly recognized as important players of inflammation. Data from experiments in mice and men revealed various intersection points between thrombosis, hemostasis, and inflammation, which are addressed and discussed in this review in detail. One such example is the intrinsic coagulation cascade that is initiated after platelet activation thereby further propagating and re-enforcing wound healing or thrombus formation but also contributing to the pathophysiology of severe diseases. FXII of the intrinsic pathway connects platelet activation with the coagulation cascade during immune reactions. It can activate the contact system thereby either creating an inflammatory state or accelerating inflammation. Recent insights into platelet biology could show that platelets are equipped with complement receptors. Platelets are important for tissue remodeling after injury has been inflicted to the endothelial barrier and to the subendothelial tissue. Thus, platelets are increasingly recognized as more than just cells relevant for bleeding arrest. Future insights into platelet biology are to be expected. This research will potentially offer novel opportunities for therapeutic intervention in diseases featuring platelet abundance.

Small Molecule Tyrosine Kinase Inhibitor Nintedanib Reduces Development of Cardiac Allograft Vasculopathy in Murine Aortic Allografts

BACKGROUND

Nintedanib is a small molecule tyrosine kinase inhibitor that blocks the action of the platelet-derived growth factor receptor (PDGFR), the vascular endothelial growth factor receptor (VEGFR) and the fibroblast growth factor receptor. All of these receptors have been shown to be involved in the development of cardiac allograft vasculopathy (CAV) after heart transplantation. We therefore hypothesized that blocking these tyrosine kinase receptors with nintedanib could prevent CAV.

METHODS

CBA/JRj (H2k) mice underwent an abdominal aortic transplantation with a graft derived from fully allogeneic C57BL/6JRj (H2b) mice. Nintedanib was given daily from the first day after transplantation until harvest on day 14 for polymerase chain reaction analysis of intragraft cytokine expression or harvest on day 30 for histological analysis of the graft.

RESULTS

Nintedanib treatment resulted in significantly reduced neointima formation in the aortic graft compared with untreated control allografts. Interestingly, the immigration of smooth muscle cells into the neointima was markedly reduced while graft infiltrating macrophages and T cells were not altered in nintedanib-treated animals. The expression of the growth factor PDGF was significantly reduced in the nintedanib group going along with a distinctly reduced expression of the corresponding receptors PDGFR α and -β.

CONCLUSIONS

Treatment with nintedanib caused a significant reduction of CAV development after aortic transplantation in mice. We hypothesize the attenuated neointima formation in nintedanib-treated animals to be mediated by a direct inhibition of intimal smooth muscle cell proliferation via reduced expression of PDGF and the appropriate receptors PDGFR α + β.

DJ1 and microRNA-214 act synergistically to rescue myoblast cells after ischemia/reperfusion injury

Ischemia/reperfusion injury is a tissue injury occurring post-reperfusion of tissues with pre-existing ischemia. A good blood supply to tissues aids in the survival of ischemic tissue, however, due to prolonged ischemia the levels of ATP decrease and pH declines leading to acidosis. Reduced ATP leads to an increase in the AMP/ATP ratio, causing cessation of intracellular calcium transport, hence calcium overload and cell death. In this study, we demonstrate the synergistic and antagonistic effect of DJ1 and microR-214 (miR-214) in rescuing myoblast C2C12 cells after ischemia/reperfusion in an in vitro model. Both DJ1 and miR-214 were cloned into a hypoxic inducible expression cassette and transfected into the C2C12 cells. We showed that DJ1 and miR-214 have synergistic effects in reducing intracellular lactate dehydrogenase and intracellular transient calcium levels after reoxygenation compared to control cells, in addition to reducing cell death via necrosis. Western blotting revealed a decrease in autophagosome formation in LC3II/I ratio and an increase in AKT expression in cells transfected with DJ1 and miR-214. Using quantitative real-time PCR, we demonstrated that DJ1 and miR-214 significantly reduced the expression of pro-apoptotic factors and autophagy compared to control. The results indicated DJ1 is an endogenous oxidative stress molecule and miR-214 is a potent inhibitor of the sodium calcium exchanger channel. DJ1 had the greatest effect to inhibiting mitochondrial cell death pathways by possibly acting as a modulator of autophagy. Additionally, we have concluded that miR-214 has an inhibitory effect on extrinsic cell death pathways such as necrosis and autophagy.