BackgroundAbnormal cardiac innervation plays an important role in arrhythmogenicity after myocardial infarction (MI). Data regarding reperfusion models and innervation abnormalities in the medium... Show moreBackgroundAbnormal cardiac innervation plays an important role in arrhythmogenicity after myocardial infarction (MI). Data regarding reperfusion models and innervation abnormalities in the medium to long term after MI are sparse. Histologic quantification of the small-sized cardiac nerves is challenging, and transmural analysis has not been performed.ObjectivesThis study sought to assess cardiac innervation patterns in transmural biopsy sections in a porcine reperfusion model of MI (MI-R) using a novel method for nerve quantification.MethodsTransmural biopsy sections from 4 swine (n = 83) at 3 months after MI-R and 3 controls (n = 38) were stained with picrosirius red (fibrosis) and beta-III-tubulin (autonomic nerves). Biopsy sections were classified as infarct core, border zone, or remote zone. Each biopsy section was analyzed with a custom software pipeline, allowing calculation of nerve density and classification into innervation types at the 1 × 1–mm resolution level. Relocation of the classified squares to the original biopsy position enabled transmural quantification and innervation heterogeneity assessment.ResultsCoexisting hyperinnervation, hypoinnervation, and denervation were present in all transmural MI-R biopsy sections. The innervation heterogeneity was greatest in the infarct core (median: 0.14; IQR: 0.12-0.15), followed by the border zone (median: 0.05; IQR: 0.04-0.07; P = 0.02) and remote zone (median: 0.02; IQR: 0.02-0.03; P < 0.0001). Only in the border zone was a positive linear relation between fibrosis and innervation heterogeneity observed (R = 0.79; P < 0.0001).ConclusionsThis novel method allows quantification of nerve density and heterogeneity in large transmural biopsy sections. In the chronic phase after MI-R, alternating innervation patterns were identified within the same biopsy section. Persistent innervation heterogeneity, in particular in the border zone biopsy sections, may contribute to late arrhythmogenicity. Show less
Background Inflammation around the tendons of interosseous muscles of the hand (interosseous tendon inflammation) was recently observed with MRI for the first time in patients with rheumatoid... Show moreBackground Inflammation around the tendons of interosseous muscles of the hand (interosseous tendon inflammation) was recently observed with MRI for the first time in patients with rheumatoid arthritis and in at-risk individuals with detectable anti-citrullinated protein antibodies, generating the hypothesis that interosseous tendon inflammation precedes clinical arthritis. To better understand the role of interosseous tendon inflammation during the development of rheumatoid arthritis, we studied the frequency of interosseous tendon inflammation in healthy individuals and in those with arthralgia that was suspected of progressing to rheumatoid arthritis (ie, clinically suspect arthralgia) and the association of interosseous tendon inflammation with other symptoms of inflamed joint tissues and with clinical arthritis development.Methods Adult (age >= 18 years) patients who presented with clinically suspect arthralgia and symptom-free (control) individuals underwent contrast-enhanced hand MRI. MRIs were evaluated for interosseous tendon inflammation on the radial and ulnar sides of the second to fifth metacarpophalangeal joints, and for synovitis, tenosynovitis, and osteitis using the rheumatoid arthritis MRI scoring system. Patients with clinically suspect arthralgia were followed up for clinical arthritis development. The presence of local tenosynovium was examined using immunohistochemistry for anti-CD55 and anti-CD68 on tissue from the hands of three embalmed bodies donated for scientific research. The primary outcome for the cross-sectional part of the study was the presence of interosseous tendon inflammation on MRI. The primary outcome for the longitudinal part of the study was development of clinical arthritis.Findings Between April 3, 2012, and May 20, 2020, 667 patients with clinically suspect arthralgia (mean age 44 years [SD 13], 504 [76%] were women and 163 [24%] were men) underwent contrast-enhanced hand MRI. Between Nov 1, 2013, and Nov 30, 2014, 193 symptom-free controls were recruited (mean age 50 years [SD 16], 136 [70%] were women and 57 [30%] were men). Two (1%) of 193 symptom-free controls had interosseous tendon inflammation. Immunohistochemistry of cadaveric hand tissues showed no tenosynovium surrounding interosseous tendons. At inclusion, 67 (10%) of 667 patients with clinically suspect arthralgia had interosseous tendon inflammation (p<00001 vs symptom-free controls). Interosseous tendon inflammation occurred more frequently if synovitis (odds ratio [OR] 22 [95% CI 12-42]), or tenosynovitis (OR 97 [55-170]), was present at metacarpophalangeal joints. A three-dimensional MRI reconstruction suggested confluency of interosseous tendon inflammation with metacarpophalangeal-flexor-tenosynovitis. 91 (16%) of 558 patients with clinically suspect arthralgia developed clinical arthritis during follow-up (median total follow-up 253 months [95% CI 251-255]). Patients with clinically suspect arthralgia with interosseous tendon inflammation had a higher risk of developing clinical arthritis (hazard ratio [HR] 45 [28-72]), which was attenuated but still significant after adjusting for concomitant synovitis, tenosynovitis, or osteitis (HR 17 [102-28]).Interpretation Interosseous tendon inflammation is almost absent in symptom-free individuals but occurs in people with clinically suspect arthralgia, in whom it correlates with symptoms and is associated with the development of clinical arthritis. The absence of local tenosynovium suggests that interosseous tendon inflammation arises from expanding local subclinical inflammation in the pre-arthritis phase of rheumatoid arthritis. Show less
In the transposition of the great arteries (TGA), alterations in hemodynamics and oxygen saturation could result in fibrotic remodeling, but histological studies are scarce. We aimed to investigate... Show moreIn the transposition of the great arteries (TGA), alterations in hemodynamics and oxygen saturation could result in fibrotic remodeling, but histological studies are scarce. We aimed to investigate fibrosis and innervation state in the full spectrum of TGA and correlate findings to clinical literature. Twenty-two human postmortem TGA hearts, including TGA without surgical correction (n = 8), after Mustard/Senning (n = 6), and arterial switch operation (ASO, n = 8), were studied. In newborn uncorrected TGA specimens (1 day-1.5 months), significantly more interstitial fibrosis (8.6% +/- 3.0) was observed compared to control hearts (5.4% +/- 0.8, p = 0.016). After the Mustard/Senning procedure, the amount of interstitial fibrosis was significantly higher (19.8% +/- 5.1, p = 0.002), remarkably more in the subpulmonary left ventricle (LV) than in the systemic right ventricle (RV). In TGA-ASO, an increased amount of fibrosis was found in one adult specimen. The amount of innervation was diminished from 3 days after ASO (0.034% +/- 0.017) compared to uncorrected TGA (0.082% +/- 0.026, p = 0.036). In conclusion, in these selected postmortem TGA specimens, diffuse interstitial fibrosis was already present in newborn hearts, suggesting that altered oxygen saturations may already impact myocardial structure in the fetal phase. TGA-Mustard/Senning specimens showed diffuse myocardial fibrosis in the systemic RV and, remarkably, in the LV. Post-ASO, decreased uptake of nerve staining was observed, implicating (partial) myocardial denervation after ASO. Show less
Dakkak, Y.J.; Dijk, B.T. van; Jansen, F.P.; Wisse, L.J.; Reijnierse, M.; Helm-van Mil, A.H.M. van der; DeRuiter, M.C. 2022
MRI-detected inflammation around the extensor tendons of metacarpophalangeal (MCP-) joints is prevalent in RA and poses a markedly increased risk of RA development when present in arthralgia... Show moreMRI-detected inflammation around the extensor tendons of metacarpophalangeal (MCP-) joints is prevalent in RA and poses a markedly increased risk of RA development when present in arthralgia patients. Such inflammation is called 'peritendinitis' since anatomy literature reports no presence of a tenosynovial sheath at these tendons. However, the presence or absence of tenosynovium at these extensor tendons has never been studied. Therefore, an anatomical and histological study of extensor tendons at the MCP-joints of three embalmed human hands was performed. Immunohistochemical staining showed the presence of markers for synovial macrophages and fibroblast-like synoviocytes bordering a natural dorsal space next to the extensor tendon, suggesting the presence of a synovial lining. This implies that contrast-enhancement on MRI around extensor tendons at MCP-joints observed in early RA and pre-RA likely represents tenosynovitis and that inflammation of this synovial tissue is an early feature of RA. Show less
In fetal aortic stenosis (AS), it remains challenging to predict left ventricular development over the course of pregnancy. Myocardial organization, differentiation and fibrosis could be potential... Show moreIn fetal aortic stenosis (AS), it remains challenging to predict left ventricular development over the course of pregnancy. Myocardial organization, differentiation and fibrosis could be potential biomarkers relevant for biventricular outcome. We present four cases of fetal AS with varying degrees of severity and associate myocardial deformation on fetal ultrasound with postmortem histopathological characteristics. During routine fetal echocardiography, speckle tracking recordings of the cardiac four-chamber view were performed to assess myocardial strain as parameter for myocardial deformation. After pregnancy termination, postmortem cardiac specimens were examined using immunohistochemical labeling (IHC) of key markers for myocardial organization, differentiation and fibrosis and compared to normal fetal hearts. Two cases with critical AS presented extremely decreased left ventricular (LV) strain on fetal ultrasound. IHC showed overt endocardial fibro-elastosis, which correlated with pathological fibrosis patterns in the myocardium and extremely disturbed cardiomyocyte organization. The LV in severe AS showed mildly reduced myocardial strain and less severe disorganization of the cardiomyocytes. In conclusion, the degree of reduction in myocardial deformation corresponded with high extent to the amount of pathological fibrosis patterns and cardiomyocyte disorganization. Myocardial deformation on fetal ultrasound seems to hold promise as a potential biomarker for left ventricular structural damage in AS. Show less
Patients with a congenital bicuspid aortic valve (BAV), a valve with two instead of three aortic leaflets, have an increased risk of developing thoracic aneurysms and aortic dissection. The... Show morePatients with a congenital bicuspid aortic valve (BAV), a valve with two instead of three aortic leaflets, have an increased risk of developing thoracic aneurysms and aortic dissection. The mechanisms underlying BAV-associated aortopathy are poorly understood. This study examined BAV-associated aortopathy in Nos3(-/-) mice, a model with congenital BAV formation. A combination of histological examination and in vivo ultrasound imaging was used to investigate aortic dilation and dissections in Nos3(-/-) mice. Moreover, cell lineage analysis and single-cell RNA sequencing were used to observe the molecular anomalies within vascular smooth muscle cells (VSMCs) of Nos3(-/-) mice. Spontaneous aortic dissections were found in ascending aortas located at the sinotubular junction in similar to 13% of Nos3(-/-) mice. Moreover, Nos3(-/-) mice were prone to developing aortic dilations in the proximal and distal ascending aorta during early adulthood. Lower volumes of elastic fibres were found within vessel walls of the ascending aortas of Nos3(-/-) mice, as well as incomplete coverage of the aortic inner media by neural crest cell (NCC)-derived VSMCs. VSMCs of Nos3(-/-) mice showed downregulation of 15 genes, of which seven were associated with aortic aneurysms and dissections in the human population. Elastin mRNA was most markedly downregulated, followed by fibulin-5 expression, both primary components of elastic fibres. This study demonstrates that, in addition to congenital BAV formation, disrupted endothelial-mediated nitric oxide (NO) signalling in Nos3(-/-) mice also causes aortic dilation and dissection, as a consequence of inhibited elastic fibre formation in VSMCs within the ascending aorta. Show less
ObjectivesIn congenital heart malformations with pulmonary stenosis to atresia an abnormal lateral ductus arteriosus to left pulmonary artery connection can lead to a localised narrowing (pulmonary... Show moreObjectivesIn congenital heart malformations with pulmonary stenosis to atresia an abnormal lateral ductus arteriosus to left pulmonary artery connection can lead to a localised narrowing (pulmonary ductal coarctation) or even interruption We investigated embryonic remodelling and pathogenesis of this area.Material and methodsNormal development was studied in WntCre reporter mice (E10.0-12.5) for neural crest cells and Nkx2.5 immunostaining for second heart field cells. Data were compared to stage matched human embryos and a VEGF120/120 mutant mouse strain developing pulmonary atresia.ResultsNormal mouse and human embryos showed that the mid-pharyngeal endothelial plexus, connected side-ways to the 6th pharyngeal arch artery. The ventral segment formed the proximal pulmonary artery. The dorsal segment (future DA) was solely surrounded by neural crest cells. The ventral segment had a dual outer lining with neural crest and second heart field cells, while the distal pulmonary artery was covered by none of these cells. The asymmetric contribution of second heart field to the future pulmonary trunk on the left side of the aortic sac (so-called pulmonary push) was evident. The ventral segment became incorporated into the pulmonary trunk leading to a separate connection of the left and right pulmonary arteries. The VEGF120/120 embryos showed a stunted pulmonary push and a variety of vascular anomalies.SummarySide-way connection of the DA to the left pulmonary artery is a congenital anomaly. The primary problem is a stunted development of the pulmonary push leading to pulmonary stenosis/atresia and a subsequent lack of proper incorporation of the ventral segment into the aortic sac. Clinically, the aberrant smooth muscle tissue of the ductus arteriosus should be addressed to prohibit development of severe pulmonary ductal coarctation or even interruption of the left pulmonary artery. Show less
Grewal, N.; Gittenberger-de Groot, A.C.; Thusen, J. von der; Wisse, L.J.; Bartelings, M.M.; DeRuiter, M.C.; ... ; Poelmann, R.E. 2020
Background: Patients with a bicuspid aortic valve (BAV) have an increased risk for aortic dilation and dissection. In this study, we provide a histological stratification of the developing aorta in... Show moreBackground: Patients with a bicuspid aortic valve (BAV) have an increased risk for aortic dilation and dissection. In this study, we provide a histological stratification of the developing aorta in the tricuspid aortic valve (TAV) and the BAV populations as a reference for future studies on aortopathy and related syndromes. Methods: Non-dilated TAV and BAV ascending aortic wall samples were collected, including 60 TAV (embryonic-70 years) and 32 BAV specimens (fetal-72 years, categorized in eight age groups. Results: In TAV, intimal development starts in the neonatal phase. After birth, the thickness of the medial layer increases significantly by increase of elastic lamellae up to and including the "young child" phase stabilizing afterwards. The BAV shows already prenatal intimal thickening becoming significantly thinner after birth subsequently stabilizing. In BAV, increase in elastic lamellae is seen between the young child and the adolescent phases, stabilizing afterwards. Conclusions: Vascular development in TAV is described in three phases: maturation, stabilization, and degeneration. For BAV, the development can be described in two phases: maturation (already prenatally) and degeneration. After birth, the development of the aorta is characterized by degeneration, leading to weakening of the ascending aortic wall and increasing the risk of aortopathy. Show less
Grewal, N.; Gittenberger-de Groot, A.C.; Thusen, J. von der; Wisse, L.J.; Bartelings, M.M.; DeRuiter, M.C.; ... ; Poelmann, R.E. 2020
Introduction Past research has demonstrated that the urethral tonus is mainly under sympathetic control. Since 5 years, a beta 3-adrenoceptor (ADRB3) agonist is available in the treatment of... Show moreIntroduction Past research has demonstrated that the urethral tonus is mainly under sympathetic control. Since 5 years, a beta 3-adrenoceptor (ADRB3) agonist is available in the treatment of overactive bladder syndrome. The presence of ADRB3 within the human urethra has not been demonstrated to date. Presence of ADRB3 in the urethra could influence urethral tonus. The aim of this study is to investigate the presence of ADRB3 in the human female urethra. Material and Methods We performed anatomical studies in five female specimens. Three specimens were obtained from the body donation program, two from female patients with muscle-invasive bladder cancer, where radical resection of bladder and urethra was performed. The urethra up till the bladder neck was separated from the rest of the bladder and freshly obtained for this study. For demonstrating ADRB3 expression, we used rabbit polyclonal anti-human ADRB3 LS-A4198. Results Expression of ADBR3 was demonstrated in the epithelial layer of all urethral parts, except at the level of the meatus. The level of ADRB3 expression was highest in the mid urethra. There was no direct contact between ADRB3 and nerve tissue. ADRB3 expression was also demonstrated in the stratified muscle layer at the level of the external urethral sphincter. Conclusions This is the first study to demonstrate the expression of ADRB3 in the human female urethra. There is an absence of a direct connection between ADRB3 and nerve tissue. Show less
