URL: http://www.clinicaltrials.gov. Unique identifier: NCT00333827.

Tissue-engineered heart valves aim to reproduce the biological properties of natural valves with anatomically correct structure and physiological performance. The closest alternative to creating an ideal heart valve substitute is to use decellularized porcine heart valves, due to their anatomy and availability. However, the immunological barrier and the structural maintenance limit the long-term physiological performance of decellularized porcine heart valves. This study investigated the extracellular matrix (ECM) structure of aortic and pulmonary porcine valves decellularized by a low concentration sodium dodecyl sulfate (SDS)-based method in order to determine the ECM scaffold (ECMS) conditions related to remodeling potential. To assess the structures of the leaflets and conduits of the heart valves, ECM components and their organization were evaluated by histology, biochemical analysis (BC), scanning electron microscopy, multiphoton microscopy, tensile test, immunofluorescence labeling (IF), and Raman microspectroscopy used to draw a profile of the cell niches. Histology and multiphoton imaging of decellularized aortic and pulmonary leaflets and conduits revealed a collagen and elastin histoarchitecture with rearrangement, loosening fibers, and glycosaminoglycan depletion confirmed by biochemistry quantification.The potential cytotoxicity of SDS residues was eliminated after 10 wash cycles. The mechanical properties of the structure of the valve indicated a functional resistance of decellularized ECM. The IF demonstrated the presence of basement membrane, suggesting a potential structure for host cell attachment. The RM analysis showed evidence of molecular interactions, suggesting conservation of the chemical composition, particularly among the protein molecular structures. The structural analyses performed in the semilunar porcine heart valves demonstrate that decellularized ECMS has structural properties that support physiological performance and potential host tissue integration. In fact, decellularized leaflet scaffolds were prone to cell interaction after human adipose-derived stromal cell seeding and culturing. Further analysis of biocompatibility, particularly the ECM-cell interaction, can elucidate the remodeling process, in preserved decellularized heart valve scaffold.

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Aneurysm of the left main coronary artery is a rare angiographic finding, with few cases described in the interAneurysms in coronary arteries are rare entities, however, with potential severe complications. Usually they are multiple and atherosclerosis is responsible for more than 50% of the diagnosed adult cases in the Western world. The most affected places are, in order of frequency, the, proximal and mid portions of the right coronary, the proximal portion of the anterior descending branch, and the proximal portion of the circumflex branch 1,2 . Aneurysm of the left coronary trunk is extremely infrequent, with little more than 30 cases described in the literature.This report has the objective of presenting a case of aneurysm of the left main coronary artery and summarizing the available data from the literature about this uncommon entity and of its yet uncertain management. Case ReportThe patient was a 42-year-old male Caucasian fisherman with a 15-day history of acute myocardial infarction not treated with thrombolitics in his city of origin, as risk factors for coronary disease, smoking, and hyperlipemia where found. At cinecoronariography, occlusion of the right coronary, critical stenosis in the proximal portion of the anterior descending branch and circumflex branch, and an aneurysm of the left main coronary artery, measuring 23.6 x 15.8mm, with stasis of contrast in its interior and an important delay in distal coronary flow (Fig.1) were documented. The left ventricle maintained adequate contractibility, with a 62% ejection fraction. With no findings in the clinical history or laboratory examinations that night suggest vasculitis or endocarditis, and with the basal disease related to aneurysm, atherosclerosis seemed to us to be the most probable cause.The patient underwent myocardial revascularization, with the implant of the left internal mammary artery for the anterior descending and grafts of the saphenous vein for the first obtuse marginal branch and for the right coronary. The consensus as to the best strategy for treatment of aneurysm was to avoid the direct approach or closure of the aneurysm. The patient evolved well in postsurgery and was discharged from ITU on the second day. In the 180º post operative, the patient remains asymptomatic with noninvasive tests negative for myocardial ischemia.