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Background and Purpose: Group III pulmonary hypertension (PH) is a highly lethal and widespread lung disorder that is a common complication in idiopathic pulmonary fibrosis (IPF) where it is considered to be the single most significant predictor of mortality. While increased levels of hyaluronan have been observed in IPF patients, hyaluronan-mediated vascular remodelling and the hyaluronan-mediated mechanisms promoting PH associated with IPF are not fully understood.Experimental Approach: Explanted lung tissue from patients with IPF with and without a diagnosis of PH was used to identify increased levels of hyaluronan. In addition, an experimental model of lung fibrosis and PH was used to test the capacity of 4-methylumbeliferone (4MU), a hyaluronan synthase inhibitor to attenuate PH. Human pulmonary artery smooth muscle cells (PASMC) were used to identify the hyaluronan-specific mechanisms that lead to the development of PH associated with lung fibrosis.Key Results: In patients with IPF and PH, increased levels of hyaluronan and expression of hyaluronan synthase genes are present. Interestingly, we also report increased levels of hyaluronidases in patients with IPF and IPF with PH. Remarkably, our data also show that 4MU is able to inhibit PH in our model either prophylactically or therapeutically, without affecting fibrosis. Studies to determine the hyaluronan-specific mechanisms revealed that hyaluronan fragments result in increased PASMC stiffness and proliferation but reduced cell motility in a RhoA-dependent manner.Conclusions and Implications: Taken together, our results show evidence of a unique mechanism contributing to PH in the context of lung fibrosis. [ABSTRACT FROM AUTHOR]

Idiopathic pulmonary fibrosis (IPF) is a lethal lung disease of unknown etiology. The development of pulmonary hypertension (PH) is considered the single most significant predictor of mortality in patients with chronic lung diseases. The processes that govern the progression and development of fibroproliferative and vascular lesions in IPF are not fully understood. Using human lung explant samples from patients with IPF with or without a diagnosis of PH as well as normal control tissue, we report reduced BMPR2 expression in patients with IPF or IPF PH. These changes were consistent with dampened P-SMAD 1/5/8 and elevated P-SMAD 2/3, demonstrating reduced BMPR2 signaling and elevated TGF- activity in IPF. In the bleomycin (BLM) model of lung fibrosis and PH, we also report decreased BMPR2 expression compared with control animals that correlated with vascular remodeling and PH. We show that genetic abrogation or pharmacological inhibition of interleukin-6 leads to diminished markers of fibrosis and PH consistent with elevated levels of BMPR2 and reduced levels of a collection of microRNAs (miRs) that are able to degrade BMPR2. We also demonstrate that isolated bone marrow-derived macrophages from BLM-exposed mice show reduced BMPR2 levels upon exposure with IL6 or the IL6 IL6R complex that are consistent with immunohistochemistry showing reduced BMPR2 in CD206 expressing macrophages from lung sections from IPF and IPF PH patients. In conclusion, our data suggest that depletion of BMPR2 mediated by a collection of miRs induced by IL6 and subsequent STAT3 phosphorylation as a novel mechanism participating to fibroproliferative and vascular injuries in IPF. [ABSTRACT FROM AUTHOR]

Hemangioma of the heart presenting as a primary cardiac tumor is extremely rare, accounting for approximately 2% of all primary resected heart tumors. Only a few cases of cardiac hemangiomas have been reported to arise from the left atrial wall. In this case report we share our experience in the diagnosis and surgical resection of a large (9 x 7 cm) left atrial hemangioma and reconstruction of the heart using porcine urinary bladder membrane. [ABSTRACT FROM AUTHOR]

For any given cardiac surgery, there are two invasive components: the surgical approach and the cardiopulmonary bypass circuit. The standard approach for cardiac surgery is the median sternotomy, which offers unrestricted access to the thoracic organs-the heart, lung, and major vessels. However, it carries a long list of potential complications such as wound infection, brachial plexus palsies, respiratory dysfunction, and an unpleasant-looking scar. The cardiopulmonary bypass component also carries potential complications such as end-organ dysfunction, coagulopathy, hemodilution, bleeding, and blood transfusion requirement. Furthermore, the aortic manipulation during cannulation and cross clamping increases the risk of dissection, arterial embolization, and stroke. Minimally invasive cardiac surgery is an iconic event in the history of cardiothoracic medicine and has become a widely adapted approach as it minimizes many of the inconvenient side effects associated with the median sternotomy and bypass circuit placement. This type of surgery requires the use of novel perfusion strategies, especially in patients who hold the highest potential for postoperative morbidity. Cannulation techniques are a fundamental element in minimally invasive cardiac surgery, and there are numerous cannulation procedures for each type of minimally invasive operation. In this review, we will highlight the strategies and pitfalls associated with a minimally invasive cannulation. [ABSTRACT FROM AUTHOR]

Treatment of patients with INTERMACS class I heart failure can be very challenging, and temporary long-term device support may be needed. In this article, we review the currently available temporary support devices in order to support these severely ill patients with decompensated heart failure. Strategies of using a temporary assist as a bridge to long-term device support are also discussed. [ABSTRACT FROM AUTHOR]

The application of three-dimensional (3D) printing enables the creation of material objects from digital images by depositing layers of plastic material into 3D structures and can be used for training, education, and surgical planning. We report two patients with large complex cardiac tumors where 3D technology was utilized to analyze the tumor size, location, and extension more precisely, allowing better preoperative planning and decision making. [ABSTRACT FROM AUTHOR]

Primary cardiac sarcomas are rare and carry a grave prognosis. Improved survival requires a complete margin negative resection of the tumor. These surgical resections are often large and complex, requiring extensive reconstructive procedures. The appropriate material for cardiac reconstruction is not known. We have used glutaraldehyde-fixed bovine pericardium in our early series but have recently employed the MatriStem® Surgical Matrix PSMX membrane (ACell®, Inc.; Columbia, MD), a unique proprietary urinary bladder matrix derived from porcine urinary bladder with the potential for viability and tissue ingrowth. In our study of six patients at this institution, all six underwent successful surgical resection and repair with the MatriStem acellular porcine urinary bladder membrane (ACell). The postoperative course was uncomplicated in all patients, and they are still alive at this time. An aggressive surgical approach to cardiac tumors can possibly lead to complete resection but often requires reconstruction of the cardiac tissue with a membrane. We were able to achieve acceptable results in our cardiac reconstruction by using the ACell extracellular matrix to reconstruct the defect following tumor resection. Longer-term follow-up in these patients, including imaging studies, will be necessary to demonstrate the durability and integrity of the reconstruction. [ABSTRACT FROM AUTHOR]

We report a patient with class III heart failure symptoms due to mitral regurgitation (MR) subsequent to nonischemic cardiomyopathy. The patient underwent percutaneous transcatheter mitral valve repair using a single MitraClip, which reduced the MR; however it created mild-to-moderate mitral stenosis, which progressed to severe mitral stenosis. Subsequently the patient underwent mitral valve replacement surgery. [ABSTRACT FROM AUTHOR]

Treatment options for aortic arch disease in high-risk patients includes supra-aortic debranching and thoracic endovascular aortic repair (TEVAR). Acute ascending aortic dissection is a concerning complication of this approach and has been reported to occur in a retrograde fashion. We report a case of a 60-year-old gentleman who had undergone thoracic endovascular aortic repair with debranching and presented 31 months later with acute isolated ascending aortic dissection. The patient underwent successful total replacement of the ascending aorta with a 30-mm gelwave Valsalva™ graft using cardiopulmonary bypass. [ABSTRACT FROM AUTHOR]

Unilateral agenesis of the pulmonary artery (UAPA) is a rare congenital anomaly. This report describes a 52-year-old female who gave a long history of chronic, recurrent, left-sided pulmonary infections related to UAPA. For many years, she was managed medically but the infection continued to recur. She eventually underwent left pneumonectomy and made a good recovery. [ABSTRACT FROM AUTHOR]

Background Although extracellular xenograft repair has produced encouraging results when applied to cardiac, valvular, and specific aortic defects, its employment as a tube graft to replace the ascending aorta has not been reported. We describe a patient who underwent resection and replacement of an infected ascending aortic graft with an extracellular matrix conduit. The patient did well, but 14 months later developed a pseudoaneurysm from the staple line used to construct the extracellular matrix conduit. Methods The patient underwent a repeat sternotomy and removal of the graft. Because of the increased risk of graft failure, a homograft was felt to be more appropriate in this setting. Ultimately, we were unable to implant the homograft because it was too small for the aortic root; therefore we decided to construct a tubular graft from Cormatrix extracellular matrix (CorMatrix, Roswell, GA, USA). Fourteen months later, he presented with shortness of breath. Computed tomography scan revealed a 3.5 cm pseudoaneurysm of the ascending aorta. It appeared as if there was a disruption of the staple line in the extra cellular matrix graft. The plan was to replace it with a Dacron graft. Results The Cormatrix graft material was removed and sent for culture and histological analysis. A 28-mm Gel weave graft (Terumo Cardiovascular Systems, Ann Arbor, MI, USA) was implanted. The patient tolerated the procedure well with good hemodynamics. Conclusions Our experience suggests that the superior strength, handling characteristics, and resistance to infection make extra cellular matrix scaffold a possible alternative conduit to cryopreserved homografts. Applicability as an aortic conduit merits further investigation to better understand behavior of extra cellular matrix in this situation. doi: 10.1111/jocs.12583 (J Card Surg 2015;30:648-650) [ABSTRACT FROM AUTHOR]