Endomyocardial fibrosis is the most common restrictive cardiomyopathy worldwide. It has no specific treatment and carries a poor prognosis, since most patients present with advanced heart failure. On the basis of clinical series, regional variations in distribution have been reported within several countries in Africa, Asia, and South America, but large-scale data are lacking on the epidemiologic features and early stages of the disease. We used transthoracic echocardiography to determine the prevalence of endomyocardial fibrosis in a rural area of Mozambique. We screened a random sample of 1063 subjects of all age groups selected by clustering. Major and minor diagnostic criteria were defined, and a severity score was developed and applied. Cases were classified according to the distribution and severity of the lesions in the heart. The estimated overall prevalence of endomyocardial fibrosis was 19.8%, or 211 of 1063 subjects (95% confidence interval [CI], 17.4 to 22.2). The prevalence was highest among persons 10 to 19 years of age (28.1%, or 73 of 260 subjects [95% CI, 22.6 to 33.6]) and was higher among male than among female subjects (23.0% vs. 17.5%, P=0.03). The most common form was biventricular endomyocardial fibrosis (a prevalence of 55.5%, or 117 of 211 subjects [95% CI, 48.8 to 62.2]), followed by right-sided endomyocardial fibrosis (a prevalence of 28.0%, or 59 of 211 subjects [95% CI, 21.9 to 34.1]). Most affected subjects had mild-to-moderate structural and functional echocardiographic abnormalities. Only 48 persons with endomyocardial fibrosis (22.7%) were symptomatic. The frequency of familial occurrence was high. Endomyocardial fibrosis is common in a rural area of Mozambique. By using echocardiography, we were able to detect early, asymptomatic stages of the disease. These findings may aid in the study of the pathogenesis of the disease and in the development of new management strategies.
Background— Calcific aortic valve stenosis is a common disease in the elderly and is characterized by progressive calcification and fibrous thickening of the valve, but the cellular and molecular mechanisms are not fully understood. We hypothesized that human valve interstitial cells (ICs) are able to differentiate into osteoblast-like cells through the influence of defined mediators and that this process can be modulated pharmacologically. Methods and Results— To test this hypothesis, we treated primary cultures of human aortic valve ICs with osteogenic media, bone morphogenic proteins ([BMPs] BMP-2, BMP-4, and BMP-7), and tissue growth factor-β ([TGF-β] TGF-β1 and TGF-β3) for 21 days. These mediators induced osteoblast differentiation of valve ICs by significantly increasing the activity and expression of alkaline phosphatase ([ALP] P <0.001). A cytokine protein array revealed that atorvastatin treatment (100 μmol/L) of human valve ICs caused a downregulation in levels of expression of BMP-2, BMP-6, TGF-β1, and TGF-β3 after 24 hours. In addition, human valve ICs treated with atorvastatin in the presence of osteogenic media showed a significant reduction in ALP activity in comparison to cells treated with osteogenic media only ( P =<0.001). This was further confirmed with immunocytochemical staining of valve ICs, whereby atorvastatin markedly reduced the expression of ALP and osteocalcin induced by osteogenic media in comparison to untreated cells. Conclusions— These findings suggest that human valve ICs are capable of osteoblastic differentiation, by potential mediators which can be pharmacologically targeted by atorvastatin.
Background: To elucidate further the pathogenesis of sporadic, idiopathic pulmonary arterial hypertension (IPAH) and identify potential therapeutic avenues, differential gene expression in IPAH was examined by suppression subtractive hybridisation (SSH). Methods: Peripheral lung samples were obtained immediately after removal from patients undergoing lung transplant for IPAH without familial disease, and control tissues consisted of similarly sampled pieces of donor lungs not utilised during transplantation. Pools of lung mRNA from IPAH cases containing plexiform lesions and normal donor lungs were used to generate the tester and driver cDNA libraries, respectively. A subtracted IPAH cDNA library was made by SSH. Clones isolated from this subtracted library were examined for up regulated expression in IPAH using dot blot arrays of positive colony PCR products using both pooled cDNA libraries as probes. Clones verified as being upregulated were sequenced. For two genes the increase in expression was verified by northern blotting and data analysed using Student's unpaired two-tailed t-test. Results: We present preliminary findings concerning candidate genes upregulated in IPAH. Twenty-seven upregulated genes were identified out of 192 clones examined. Upregulation in individual cases of IPAH was shown by northern blot for tissue inhibitor of metalloproteinase-3 and decorin (P < 0.01) compared with the housekeeping gene glyceraldehydes-3-phosphate dehydrogenase. Conclusion: Four of the up regulated genes, magic roundabout, hevin, thrombomodulin and sucrose non-fermenting protein-related kinase-1 are expressed specifically by endothelial cells and one, muscleblind-1, by muscle cells, suggesting that they may be associated with plexiform lesions and hypertrophic arterial wall remodelling, respectively.
1 December 2014 in Global Cardiology Science and Practice
The use of radiation in medicine is now pervasive and routine. From their crude beginnings 100 years ago, diagnostic radiology, nuclear medicine and radiation therapy have all evolved into advanced techniques, and are regarded as essential tools across all branches and specialties of medicine. The inherent properties of ionizing radiation provide many benefits, but can also cause potential harm. Its use within medical practice thus involves an informed judgment regarding the risk/benefit ratio. This judgment requires not only medical knowledge, but also an understanding of radiation itself. This work provides a global perspective on radiation risks, exposure and mitigation strategies.
The lungs are the primary target of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, with severe hypoxia being the cause of death in the most critical cases. Coronavirus disease 2019 (COVID-19) is extremely heterogeneous in terms of severity, clinical phenotype and, importantly, global distribution. Although the majority of affected patients recover from the acute infection, many continue to suffer from late sequelae affecting various organs, including the lungs. The role of the pulmonary vascular system during the acute and chronic stages of COVID-19 has not been adequately studied. A thorough understanding of the origins and dynamic behaviour of the SARS-CoV-2 virus and the potential causes of heterogeneity in COVID-19 is essential for anticipating and treating the disease, in both the acute and the chronic stages, including the development of chronic pulmonary hypertension. Both COVID-19 and chronic pulmonary hypertension have assumed global dimensions, with potential complex interactions. In this Review, we present an update on the origins and behaviour of the SARS-CoV-2 virus and discuss the potential causes of the heterogeneity of COVID-19. In addition, we summarize the pathobiology of COVID-19, with an emphasis on the role of the pulmonary vasculature, both in the acute stage and in terms of the potential for developing chronic pulmonary hypertension. We hope that the information presented in this Review will help in the development of strategies for the prevention and treatment of the continuing COVID-19 pandemic.