Cardiovascular pathology in vasculitis.

Vasculitides are diseases that can affect any vessel. When cardiac or aortic involvement is present, the prognosis can worsen significantly. Pathological assessment often plays a key role in reaching a definite diagnosis of cardiac or aortic vasculitis, particularly when the clinical evidence of a systemic inflammatory disease is missing. The following review will focus on the main histopathological findings of cardiac and aortic vasculitides.

Effects of sacubitril-valsartan on remodelling, fibrosis and mitochondria in a murine model of isoproterenol-induced left ventricular dysfunction.

BACKGROUND: Sacubitril/valsartan has been demonstrated to promote left ventricular (LV) reverse remodelling and improve outcomes in patients with heart failure (HF) with reduced ejection fraction (EF). Its molecular and tissue effects have not been fully elucidated yet, due to the paucity of preclinical studies, mostly based on ischaemic models. We aimed to evaluate the effects of sacubitril/valsartan on LV remodelling, myocardial fibrosis and mitochondrial biology in a murine model of non-ischaemic LV dysfunction. METHODS: Adult transgenic male mice with cardiac-specific hyperaldosteronism (AS mice) received subcutaneous isoproterenol injections to induce LV systolic dysfunction. After 7 days, mice were randomized to a 2-week treatment with saline (ISO-AS n = 15), valsartan (ISO + V n = 12) or sacubitril/valsartan (ISO + S/V n = 12). Echocardiography was performed at baseline, at day 7, and after each of the 2 weeks of treatment. After sacrifice at day 21, histological and immunochemical assays were performed. A control group of AS mice was also obtained (Ctrl-AS n = 8). RESULTS: Treatment with sacubitril/valsartan, but not with valsartan, induced a significant improvement in LVEF (p = 0.009 vs ISO-AS) and fractional shortening (p = 0.032 vs ISO-AS) after 2- week treatment. In both ISO + V and ISO + S/V groups, a trend toward reduction of the cardiac collagen 1/3 expression ratio was detected. ISO + V and ISO + S/V groups showed a significant recovery of mitochondrial morphology and inner membrane function meant for oxidative phosphorylation. CONCLUSION: In a murine model of non-ischaemic HF, sacubitril/valsartan proved to have beneficial effects on LV systolic function, and on cardiac energetics, by improving mitochondrial activity.

The cardiovascular pathologist in the aortic team.

Aortic diseases require a multidisciplinary management for diagnosis, treatment and follow-up with better outcomes in referral centers using a team-based approach. The setting up of a multi-disciplinary aortic team for the discussion of complex cases has been already proposed; it is also supported by the ACC/AHA. Surgeons and radiologists, more or less other physicians such as cardiologists, geneticists, rheumatologists/internal medicine specialists and pathologists are involved into such a team. The role of the cardiovascular pathologist is to examine the aortic specimens, to diagnose and classify the aortic lesions. Herein, the role of the pathologist in the aortic team is discussed and the pathobiology of aortic diseases is reviewed for reference by pathologists. The aortic specimens are mainly obtained from emergency or elective surgical procedures on the thoracic aorta, less frequently from organ/tissue (including cardiac or heart valve) donors, post-mortem procedures or abdominal aortic surgery. In the last decade, together with the progress of medical sciences, the histological definitions and classifications of the aortic pathology are undergoing thorough revisions that are addressed to an etiopathogenetic approach because of possible clinico-pathological correlations, therapeutic and prognostic impact. Pathologists may also have an important role in research and teaching. Therefore, histological analyses of the aortic specimens require adequate sample processing and pathologist expertise because histology contributes to definite diagnosis, correct management of patients and even (in genetic diseases) families, but also to research in the challenging field of aortopathies.

Valvular heart disease in patients with cardiac amyloidosis.

Cardiac amyloidosis (CA) is an underdiagnosed condition caused by the deposition of misfolded proteins, namely immunoglobulin light chains and transthyretin, in the extracellular spaces of the heart. Any cardiovascular structure can be affected by amyloid infiltration, including the valves. Amyloid accumulation within the cardiac valves may lead to their structural and functional impairment, with a profound impact on patients' prognosis and quality of life. The most common forms of valvular disease in CA are aortic stenosis (AS), mitral regurgitation (MR), and tricuspid regurgitation (TR). CA and AS share similar risk factors, disease mechanisms, and remodeling patterns, which make their diagnosis particularly challenging. Patients with both CA and AS experience worse outcomes than CA or AS alone, and transcatheter aortic valve replacement may represent a useful therapeutic strategy in this population. Data on MR and TR are quite limited and mainly coming from case reports or small series. This review paper will summarize our current understanding on the epidemiology, disease mechanisms, echocardiographic features, clinical implications, and therapeutic options of AS, MR, and TR in patients with CA.

Effects of pirfenidone on scar size and ventricular remodeling after myocardial infarction: a preclinical study.

BACKGROUND: An intense fibrotic response after myocardial infarction (MI) may lead to scar expansion and left ventricular (LV) remodeling. We investigated the effects of the antifibrotic drug pirfenidone in this setting. METHODS: Male Wistar rats were randomized to: sham procedure (n = 13), reperfused MI-induced by ligating the left anterior descending artery (LAD) for 45 min (n = 17), reperfused MI plus standard therapy (aspirin, angiotensin-converting enzyme inhibitor, beta blocker, and mineralocorticoid receptor antagonist) (n = 17), reperfused MI plus pirfenidone alone (n = 17), or reperfused MI plus standard therapy and pirfenidone (n = 17). Rats surviving MI induction underwent cardiac magnetic resonance scans after 72 h and 30 days from MI, and were sacrificed on day 31. RESULTS: Rats completing the whole protocol numbered 11 in the sham group, 9 in the untreated MI group, 8 in the standard treatment group, 9 in the pirfenidone alone group, and 9 in the standard treatment plus pirfenidone group. No significant differences emerged between LV volumes, ejection fraction or mass at 30 days or the differences from 72 h to 30 days. Small, nonsignificant differences between rats on pirfenidone alone vs. those on standard therapy emerged. The total extent of LV fibrosis, quantified as area and percentage of the tissue sample, did not differ significantly between rats on pirfenidone alone vs. those on standard therapy alone. CONCLUSION: Pirfenidone does not have additional effects on LV remodeling or fibrosis compared with standard therapy, but its effects are similar to standard therapy alone.

Colchicine added to standard therapy further reduces fibrosis in pigs with myocardial infarction.

BACKGROUND: The anti-inflammatory drug colchicine improves the outcome of patients with myocardial infarction (MI). As an intense inflammatory and fibrotic response after MI may lead to scar expansion and left ventricular (LV) remodeling, the clinical benefit of colchicine could be related to a positive effect on the infarct scar and LV remodeling. METHODS: Pigs underwent left anterior descending artery occlusion through an angioplasty balloon for 90 min and were then randomized into two groups: standard therapy [ACE inhibitor, beta blocker, mineralocorticoid receptor antagonist (MRA), aspirin] plus colchicine (n = 14) or standard therapy alone (n = 13). The pigs were treated for 30 days and underwent two cardiac magnetic resonance (CMR) scans at 72 h and 30 days. The pigs were then sacrificed the day after the second CMR. The primary efficacy end point was the extent of fibrosis in the infarct zone (calculated on eight samples from this zone and averaged). RESULTS: In the hearts explanted after 31 days, pigs in the colchicine group had less fibrosis in the infarct zone than the other animals [41.6% (20.4-51.0) vs. 57.4% (42.9-66.5); P = 0.022]. There was a trend toward a higher myocardial salvage index (MSI; an index of the efficacy of revascularization) in pigs on colchicine (P = 0.054). Conversely, changes in LV volumes, ejection fraction and mass did not differ between groups. CONCLUSION: Colchicine therapy for 1 month after reperfused MI further reduces myocardial fibrosis when added to standard therapy, while it does not have additional effects on LV remodeling.

Correction: Aquaro et al. Post-Mortem Cardiac Magnetic Resonance in Explanted Heart of Patients with Sudden Death. Int. J. Environ. Res. Public Health 2022, 19, 13395.

The authors wish to make the following corrections to this paper [...].

Hamartoma of mature cardiomyocytes presenting with atypical angina, 18F-fluorodeoxyglucose positron emission tomography uptake, and myocardial bridging: a case report.

Aim: Hamartoma of mature cardiomyocytes is a rare tumor and the present case shows a complex diagnostic pathway to understand its nature and treatment options in a young patient. The myocardial bridge was also part of the clinical evaluation discovered during the diagnostic workout. Methods and results: A 27-year-old woman with atypical chest pain and a normal electrocardiogram received the diagnosis of neoformation of the interventricular septum with 18F-fluorodeoxyglucose (18F-FDG) uptake, and evidence of myocardial bridging on coronary angiography. On suspicion of malignancy, coronary unroofing and surgical biopsy was performed. The final diagnosis was hamartoma of mature cardiomyocytes. Conclusion: This case offers great insight into medical reasoning and decision-making process. Given the history of chest pain, the patient was evaluated for possible ischemic, embolic, or vascular causes. Given a left ventricular wall thickness ≥15 mm, hypertrophic cardiomyopathy (HCM) should always be suspected; nuclear magnetic resonance imaging is essential to distinguish between HCM. The magnetic resonance imaging is also critical in distinguishing HCM itself from tumoral phenocopies. To rule out a neoplastic process, 18F-FDG positron emission tomography (PET) was used. A surgical biopsy was performed, and the final diagnosis was completed after the immune-histochemistry study. A myocardial bridge was found during preoperative coronagraphy and was treated accordingly.

Tissue Characterization in Cardiac Amyloidosis.

Cardiac amyloidosis (CA) has long been considered a rare disease, but recent advancements in diagnostic tools have led to a reconsideration of the epidemiology of CA. Amyloid light-chain (AL) and transthyretin (ATTR) amyloidoses are the most common forms of cardiac amyloidosis. Due to the distinct treatments and the different prognoses, amyloid typing is crucial. Although a non-biopsy diagnosis can be obtained in ATTR amyloidosis when certain diagnostic criteria are fulfilled, tissue characterization still represents the gold standard for the diagnosis and typing of CA, particularly in AL amyloidosis. The present review focuses on the status of tissue characterization in cardiac amyloidosis, from histochemistry to immunohistochemistry and mass spectrometry, as well as on its future directions.

Post-Mortem Cardiac Magnetic Resonance in Explanted Heart of Patients with Sudden Death.

BACKGROUND: We sought to evaluate the diagnostic accuracy of post-mortem cardiac magnetic resonance (PMCMR) of explanted hearts to detect the cardiac causes of sudden death. METHODS: PMCMR was performed in formalin-fixed explanted hearts of 115 cases of sudden death. Histological sampling of myocardium was performed using two different approaches: (1) guideline-based sampling; (2) guideline-based plus PMCMR-driven sampling. RESULTS: Forensic diagnosis of cardiac cause of death was ascertained in 72 (63%) patients. When the guideline-driven histological sampling was used, the PMCMR interpretation matched with final forensic diagnosis in 93 out of 115 cases (81%) with sensitivity of 88% (79-95%), specificity of 65% (47-80%), PPV of 84% (78-90%), NPV of 73% (58-84%), accuracy of 81% (72-88%), and AUC of 0.77 (0.68-0.84). When a PMCMR-driven approach was added to the guideline-based one, the matching increased to 102 (89%) cases with a PMCMR sensitivity of 89% (80-94%), a specificity of 86% (67-96%), PPV of 95% (89-98%), NPV of 73% (59-83%), accuracy of 89% (81-93%), and AUC of 0.88 (0.80-0.93). CONCLUSIONS: PMCMR has high accuracy to identify the cardiac cause of sudden death and may be considered a valid auxilium for forensic diagnosis. PMCMR could improve histological diagnosis in conditions with focal myocardial involvement or demonstrating signs of myocardial ischemia.

Artificial chordae for mitral valve repair.

BACKGROUND: Mitral valve repair using expanded polytetrafluoroethylene sutures to replace mitral chordae tendineae is a well-established procedure. However, the incidence of neo-chordae failure causing recurrent mitral regurgitation is not well defined. METHODS: We have reviewed the reported cases of complications after mitral valve repair related to the use of neo-chordae. This study was mainly carried out through PubMed, Medline, and Google Chrome websites. RESULTS: We have identified a total of 26 patients presenting with rupture of polytetrafluoroethylene neo-chordae, mostly being described as isolated cases. Few other cases of recurrent mitral regurgitation with hemolysis were found, where reoperation was not caused by neo-chordal failure but most likely by technical errors. At pathological investigation the findings were substantially similar in all reported cases. The neo-chordae retained their length and pliability, became covered with host tissue and rupture was mainly related to suture size. Mild calcification was observed not interfering with chordal function; chordal infection did never occur. CONCLUSIONS: The use of artificial neo-chordae provides excellent late results with durable mitral valve repair stability. Chordal rupture may occur late postoperatively leading to reoperation because of recurrent mitral regurgitation. Despite its rarity, this potential complication should not be overlooked during follow-up of patients after mitral valve repair using artificial neo-chordae.

Myocardial Infarction Following COVID-19 Vaccine Administration: Post Hoc, Ergo Propter Hoc?

Vaccination against coronavirus disease 2019 (COVID-19) is the safest and most effective strategy for controlling the pandemic. However, some cases of acute cardiac events following vaccine administration have been reported, including myocarditis and myocardial infarction (MI). While post-vaccine myocarditis has been widely discussed, information about post-vaccine MI is scarce and heterogenous, often lacking in histopathological and pathophysiological details. We hereby present five cases (four men, mean age 64 years, range 50-76) of sudden death secondary to MI and tightly temporally related to COVID-19 vaccination. In each case, comprehensive macro- and microscopic pathological analyses were performed, including post-mortem cardiac magnetic resonance, to ascertain the cause of death. To investigate the pathophysiological determinants of MI, toxicological and tryptase analyses were performed, yielding negative results, while the absence of anti-platelet factor 4 antibodies ruled out vaccine-induced thrombotic thrombocytopenia. Finally, genetic testing disclosed that all subjects were carriers of at least one pro-thrombotic mutation. Although the presented cases do not allow us to establish any causative relation, they should foster further research to investigate the possible link between COVID-19 vaccination, pro-thrombotic genotypes, and acute cardiovascular events.

Pre-embedding of small biopsies using a Paraform gel system in a high throughput pathology laboratory.

In histology, the correct handling and orientation of small/thin biopsies is often crucial for diagnosis. Automation is progressively growing and modifying the routine work in the histopathology laboratories, providing new chances for quality improvement and workload optimization. We have tested the use of Paraform orientation gels together with an automated embedding system for processing small/thin biopsies, first skin, but also other tissue/organ biopsies. The study aimed to assess the benefits and challenges of routinely using orientation gels in a high throughput pathology laboratory. Gel introduction required a short training of the pathologists, including trainees, at grossing; it did not cause significant delay at grossing, interference with embedding, or microtome steps, whereas re-do inclusions and re-cut slides were significantly reduced. In conclusion, orientation gel and automatic embedding constituted an efficient system for small/thin biopsies that had to be correctly placed and orientated, allowing the re-modeling of technicians' workflow and very safe handling of small/thin biopsies that were not manipulated further after grossing.

Atrial amyloidosis: mechanisms and clinical manifestations.

Cardiac amyloidosis (CA) is now recognized as an important cause of heart failure. Increased wall thickness and diastolic dysfunction of the left ventricle are the most easily detectable manifestations of CA, but amyloid accumulates in all cardiac structures. Involvement of the left and right atria may be due to the haemodynamic effects of ventricular diastolic dysfunction, the effects of amyloid infiltration into the atrial wall, and the cardiotoxic damage of atrial cardiomyocytes by amyloid precursors. Atrial amyloidosis is an early manifestation of CA, and is associated with an increased risk of atrial fibrillation and thromboembolic events. Furthermore, atrial amyloidosis can be found even in the absence of systemic disease and ventricular involvement. This condition is named isolated atrial amyloidosis and is due to a local overproduction of atrial natriuretic peptide. In this review we summarize the evidence on the mechanisms and clinical relevance of atrial amyloidosis.

Sclerosing Paragangliomas: Correlations of Histological Features with Patients' Genotype and Vesicular Monoamine Transporter Expression.

Paragangliomas and pheochromocytomas are rare neuroendocrine tumors, carrying a germ-line mutation in 40% patients. Sclerosis is a rare histological feature in these tumors. We investigated the possible correlations between histological findings, first sclerosis, immunoreactivity for vesicular catecholamine transporters (VMAT1/VMAT2) and patients' genotype in a consecutive series of 57 tumors (30 paragangliomas and 27 pheochromocytomas) from 55 patients. The M-GAPP grading system, sclerosis (0-3 scale) and VMAT1/VMAT2 (0-6 scale) immunoreactivity scores were assessed. Germ-line mutations of Succinate Dehydrogenase genes, RET proto-oncogene and Von Hippel Lindau tumor suppressor gene were searched. A germ-line mutation was found in 25/55 (45.5%) patients, mainly with paraganglioma (N = 14/30, 46,66%). Significant (score ≥ 2) tumor sclerosis was found in 9 (16.1%) tumors, i.e., 7 paragangliomas and 2 pheochromocytomas, most of them (8/9) from patients with a germ-line mutation. M-GAPP score was higher in the mutation status (in 76% of patients involving the SDHx genes, in 12% the RET gene and in the remaining 12% the VHL gene) and in tumors with sclerosis (p < 0.05). Spearman's rank correlation showed a strong correlation of germ-line mutations with M-GAPP (p < 0.0001) and sclerosis (p = 0.0027) scores; a significant correlation was also found between sclerosis and M-GAPP scores (p = 0.029). VMAT1 expression was higher in paragangliomas than in pheochromocytomas (p = 0.0006), the highest scores being more frequent in mutation-bearing patients' tumors (p < 0.01). VMAT2 was highly expressed in all but two negative tumors. Sclerosis and VMAT1 expression were higher in paragangliomas than in pheochromocytomas; tumor sclerosis, M-GAPP and VMAT1 scores were associated to germ-line mutations. Sclerosis might represent a histological marker of tumor susceptibility, prompting to genetic investigations in paragangliomas.

Sex-related differential susceptibility to ponatinib cardiotoxicity and differential modulation of the Notch1 signalling pathway in a murine model.

Ponatinib (PON), a tyrosine kinase inhibitor approved in chronic myeloid leukaemia, has proven cardiovascular toxicity. We assessed mechanisms of sex-related PON-induced cardiotoxicity and identified rescue strategies in a murine model. PON+scrambled siRNA-treated male mice had a higher number of TUNEL-positive cells (%TdT+6.12 ± 0.17), higher percentage of SA-ß-gal-positive senescent cardiac area (%SA-ß-gal 1.41 ± 0.59) and a lower reactivity degree (RD) for the survival marker Bmi1 [Abs (OD) 5000 ± 703] compared to female (%TdT+3.75 ± 0.35; %SA-ß-gal 0.77 ± 0.02; Bmi1 [Abs (OD) 8567 ± 2173]. Proteomics analysis of cardiac tissue showed downstream activation of cell death in PON+siRNA scrambled compared to vehicle or PON+siRNA-Notch1-treated male mice. Upstream analysis showed beta-oestradiol activation, and downstream analysis showed activation of cell survival and inhibition of cell death in PON+scrambled siRNA compared to vehicle or PON+siRNA-Notch1-treated female mice. PON+scrambled siRNA-treated mice also had a downregulation of cardiac actin-more marked in males-and vessel density-more marked in females. Female hearts showed greater cardiac fibrosis than their male counterparts at baseline, with no significant change after PON treatment. PON+siRNA-scrambled mice had less fibrosis than vehicle or PON+siRNA-Notch1-treated mice. The left ventricular systolic dysfunction showed by PON+scrambled siRNA-treated mice (male %EF 28 ± 9; female %EF 36 ± 7) was reversed in both PON+siRNA-Notch1-treated male (%EF 53 ± 9) and female mice (%EF 52 ± 8). We report sex-related differential susceptibility and Notch1 modulation in PON-induced cardiotoxicity. This can help to identify biomarkers and potential mechanisms underlying sex-related differences in PON-induced cardiotoxicity.

Oral Mucosal Melanoma.

PURPOSE: Primary oral mucosal melanoma (OMM) is a rare neoplasm accounting for the 0.2% to 0.8% of all melanomas. The aim of the present manuscript is (1) to describe 2 cases of primary OMM treated at our department, and (2) to perform a systematic literature review on primary OMM occurrence and treatment. METHODS: Two cases of primary OMM were described. A systematic review is presented in order to assess the treatment options, recurrence, metastasis development, and survival rate of primary OMM. RESULTS: Two patients were referred for the development of a lesion of the hard palate and the maxillary gingival mucosa, respectively. An incisional biopsy was performed in both patients, followed by extensive surgical resection after a thorough consideration of patient history and systemic involvement. The literature search retrieved 447 primary OMM cases. In the 30% of cases, distant metastases were already present at the time of diagnosis. The management of primary OMM most frequently involved surgical treatment and adjuvant radiotherapy. CONCLUSIONS: Primary OMM still represents a challenge for the clinician, as the diagnosis is often performed when metastases have already developed. The prognosis is generally poor, thus highlighting the need for further investigations to improve early diagnosis.

Correlation between testicular volume and histological findings in children with unilateral cryptorchidism: Potential impact on future fertility.

OBJECTIVES: Our aim is to assess the correlation between testicular volume and histological findings in children with unilateral cryptorchidism. METHODS: From September 2016 to August 2018, from 60 patients surgically treated for cryptorchidism, 45 children were enrolled in this single-center prospective study. Depending on the degree of testicular volume reduction, patients were divided into Group 1 with <20% reduction and Group 2 with reduction ⩾20%. Patients underwent unilateral orchidopexy and simultaneous biopsy of the undescended testis. Tanner stage was assigned. Tubular Fertility Index was measured. RESULTS: Group 1 included 20 patients (44.4%) and Group 2 included 25 patients (55.5%). Mean age was 2.10 years (range 12 months-3.8 years) in Group 1 and 2.8 years (range 18 months-4.41 years) in Group 2. Although there is a positive correlation between testicular volume and Tubular Fertility Index, no significant association was found between groups (p-value = 0.29). Furthermore, histological patterns did not differ significantly among groups. CONCLUSIONS: The degree of volume reduction in undescended testis does not seem to correlate significantly with the severity of histological changes that accompany cryptorchidism. Tubular Fertility Index could serve as objective tool for the assessment of future fertility.