Search

Pulmonary capillary hemangiomatosis is a rare form of pulmonary artery hypertension; to date, only few descriptions of myocardial pathology in pulmonary capillary hemangiomatosis have been reported in the literature. We report the case of a Japanese female patient who was diagnosed with pulmonary capillary hemangiomatosis combined with acute myocardial inflammation on performing autopsy. She was admitted to our hospital because of acute pneumonia and subsequently suddenly developed severe hypoxemia with breathing difficulty and died 13 days after admission. At autopsy, the histology of the lung was consistent with pulmonary capillary hemangiomatosis. Additionally, a diffuse severe infiltration of inflammatory cells was associated with edema in the myocardium. Myocytolysis was limited and fibrosis was absent. To the best of our knowledge, pulmonary capillary hemangiomatosis with acute myocarditis-like histological findings has been described for the first time through our case.

Tafamidis meglumine, a transthyretin (TTR) stabilizer, is effective in delaying the progression of neuropathy in TTR amyloidosis with Val30Met mutations. However, its efficacy in TTR amyloid cardiomyopathy is not fully elucidated. Herein, we report a 73-year-old Japanese man with a diagnosis of TTR amyloid cardiomyopathy with Val30Met mutation treated with tafamidis. To evaluate treatment response, cardiac magnetic resonance imaging was performed before and after 12 months of tafamidis treatment. Native T1, extracellular volume, and left ventricular mass showed no obvious worsening, and findings of other diagnostic studies also supported the efficacy of tafamidis to delay the progression of amyloid cardiomyopathy. Our case suggests that serial native T1 and extracellular volume may be novel non-invasive imaging methods to monitor the treatment response to TTR stabilizers in cardiac amyloidosis and also that tafamidis may be effective in suppressing cardiac progression in TTR amyloid cardiomyopathy with Val30Met mutation.

Background Dilated cardiomyopathy (DCM) is the most common cardiomyopathy and causes left ventricular enlargement and contractile dysfunction, with a poor prognosis. The mechanisms underlying the disease process have not been precisely identified, but recent evidence has suggested that the activation of myocardial inflammation is involved in the deterioration associated with the condition. Methods and results Biopsy samples from 182 consecutive DCM patients were immunohistochemically stained with antibodies specific to CD3 (T lymphocytes), CD68 (whole macrophages), and CD163 (M2 macrophages), and each type of infiltrating cell was counted. Masson's trichrome staining was used to determine the collagen area fraction (CAF) in each sample. Patients were followed up for 6.9 ± 2.4 years, and their clinical data were obtained for analysis. Median (interquartile range) numbers of myocardial CD3, CD68, and CD163-cell infiltrates were 8.1 (4.0–14.2)/mm2, 22.3 (12.1–36.0)/mm2, and 6.5 (2.0–14.0)/mm2, respectively. Patients with higher counts of infiltrating CD3-, CD68-, and CD163-positive cells had significantly poorer outcomes (P = 0.007, P = 0.011, and P = 0.022, respectively). A high CD163-positive infiltrate count was independently associated with worse outcome in multivariate Cox regression analysis (hazard ratio 1.77, P = 0.004), and multivariate linear regression analysis revealed that the CD163 cell count was an independent determinant of CAF (P

Heart transplantation started in Japan in 1999. Since then, 50 transplants have been performed at our center. We performed histopathological analyses of the 50 explanted hearts and the post-transplant biopsy specimens. The median age of recipients was 39 years. The primary diseases before transplant were idiopathic dilated cardiomyopathy in 33 patients (66%), hypertrophic cardiomyopathy in seven (14%), restrictive cardiomyopathy in one, arrhythmogenic right ventricular cardiomyopathy in one, and secondary cardiomyopathy in eight (16%). Before transplantation, 47 patients (94%) had left ventricular assist devices. No severe cardiovascular failure due to allograft rejection occurred. The post-transplant survival rate was 97.6% at 1 year and 93.1% at 10 years. One recipient was lost to sepsis from myelodysplastic syndrome in the fourth year, one died of multiple organ failure and peritonitis 8 months after transplant. Another patient died of recurrent post-transplant lymphoproliferative disorders (PTLD). Mild cardiac dysfunction occurred in seven recipients in the early postoperative period. Moderate acute cellular rejection occurred in six patients (12%), and antibody-mediated rejection occurred in three (6%). The number of heart transplants performed in Japan is very small. However, the outstanding 10-year survival rate is due to donor evaluation and post-transplant care resulting in low grade rejection. Pathological evaluation has also greatly contributed to the results.

Retinoic acid (RA) is a vitamin A derivative that exerts pleiotropic biological effects. Intracellular transport and metabolism of RA are regulated by cellular retinol-binding proteins (CRBP). CRBP-1 is transiently expressed in granulation tissue fibroblasts during wound healing; however, its role in cardiac remodeling remains unknown. A rat myocardial infarction (MI) model was established by ligation of the left coronary artery, and hearts were obtained at 3, 6, 15, 30 and 45 days after operation. Heart sections were examined immunohistochemically using anti-vimentin, anti-α-smooth muscle actin (α-SMA), anti-matrix metalloproteinase (MMP)-2, anti-MMP-9 and anti-CRBP-1 antibodies. Infarction involved 48.8 ± 3.6% of the left ventricle and was followed by an important cardiac remodeling. Vimentin-positive fibroblastic cells including α-SMA-positive myofibroblasts expressed CRBP-1 at 3-, 6-, and 15-days after MI. Expression of CRBP-1 reached a maximum at 6-days after infarction. Thereafter, CRBP-1 expression was dramatically decreased, showing a similar tendency to MMP expression. Human heart specimens of individuals with a recent myocardial infarction demonstrated presence of CRBP-1-positive fibroblasts by immunohistochemistry. We have demonstrated that CRBP-1 is transiently expressed by fibroblasts during cardiac remodeling. Our results suggest that CRBP-1 plays a role in ventricular remodeling after MI allegedly through its RA binding activity.

Plexiform lesions in pulmonary arteries are a characteristic histological feature for idiopathic pulmonary arterial hypertension (IPAH). The pathogenesis of the plexiform lesion is not fully understood, although it may be related to endothelial cell dysfunction and local inflammation. CD44 is a cell adhesion molecule and it is also involved in angiogenesis, endothelial cell proliferation and migration. The expression of CD44 was examined in lung plexiform lesions obtained from patients with IPAH (IPAH group, n= 7) and pulmonary arterial hypertension associated with atrial septal defect (ASD-PAH group, n= 4). Expression of CD44 was detected in 49 out of 52 plexiform lesions (93%) from all patients in the IPAH group, whereas 31 plexiform lesions obtained from the ASD-PAH group lacked CD44 positivity by immunohistochemistry. In the IPAH group, CD44 was localized in the endothelial cells of microvessels within plexiform lesions and activated T cells in and around the lesions. Furthermore, T cell infiltration and endothelial cell proliferation activity were prominent in the plexiform lesions of the IPAH group, compared to those of the ASD-PAH group. These findings suggest that CD44 and activated T cell infiltration play an important role in the development of plexiform lesions particularly in IPAH.

Aim Dilated cardiomyopathy (DCM) has a variety of causes, and no useful approach to predict left ventricular (LV) remodelling and long-term outcome has yet been established. Myocardial tenascin-C (TNC) is known to appear under pathological conditions, possibly to regulate cardiac remodelling. The aim of this study was to clarify the significance of myocardial TNC expression in LV remodelling and the long-term outcome in DCM. Methods and results One hundred and twenty-three consecutive DCM patients who underwent endomyocardial biopsy for initial diagnosis were studied. Expression of TNC in biopsy sections was analysed immunohistochemically to quantify the ratio of the TNC-positive area to the whole myocardial tissue area (TNC area). Clinical parameters associated with TNC area were investigated. The patients were divided into two groups based on receiver operating characteristic analysis of TNC area to predict death: high TNC group with TNC area ≥2.3% (22 patients) and low TNC group with TNC area