Endothelial and smooth muscle cells derived from human cardiac explants demonstrate angiogenic potential and suitable for design of cell-containing vascular grafts.

BACKGROUND: Endothelial and smooth muscle cells are considered promising resources for regenerative medicine and cell replacement therapy. It has been shown that both types of cells are heterogeneous depending on the type of vessels and organs in which they are located. Therefore, isolation of endothelial and smooth muscle cells from tissues relevant to the area of research is necessary for the adequate study of specific pathologies. However, sources of specialized human endothelial and smooth muscle cells are limited, and the search for new sources is still relevant. The main goal of our study is to demonstrate that functional endothelial and smooth muscle cells can be obtained from an available source-post-surgically discarded cardiac tissue from the right atrial appendage and right ventricular myocardium. METHODS: Heterogeneous primary cell cultures were enzymatically isolated from cardiac explants and then grown in specific endothelial and smooth muscle growth media on collagen IV-coated surfaces. The population of endothelial cells was further enriched by immunomagnetic sorting for CD31, and the culture thus obtained was characterized by immunocytochemistry, ultrastructural analysis and in vitro functional tests. The angiogenic potency of the cells was examined by injecting them, along with Matrigel, into immunodeficient mice. Cells were also seeded on characterized polycaprolactone/chitosan membranes with subsequent analysis of cell proliferation and function. RESULTS: Endothelial cells isolated from cardiac explants expressed CD31, VE-cadherin and VEGFR2 and showed typical properties, namely, cytoplasmic Weibel-Palade bodies, metabolism of acetylated low-density lipoproteins, formation of capillary-like structures in Matrigel, and production of extracellular matrix and angiogenic cytokines. Isolated smooth muscle cells expressed extracellular matrix components as well as α-actin and myosin heavy chain. Vascular cells derived from cardiac explants demonstrated the ability to stimulate angiogenesis in vivo. Endothelial cells proliferated most effectively on membranes made of polycaprolactone and chitosan blended in a 25:75 ratio, neutralized by a mixture of alkaline and ethanol. Endothelial and smooth muscle cells retained their functional properties when seeded on the blended membranes. CONCLUSIONS: We established endothelial and smooth muscle cell cultures from human right atrial appendage and right ventricle post-operative explants. The isolated cells revealed angiogenic potential and may be a promising source of patient-specific cells for regenerative medicine.

Acute superior mesenteric artery embolism: reperfusion with AngioJet hydrodynamic suction thrombectomy and pharmacologic thrombolysis with the EKOS catheter.

Acute mesenteric ischemia is commonly treated by surgical exploration and open thrombectomy. Very few reports describe using newer, minimally invasive methods which utilize catheter-based mechanical and pharmacological thrombolysis. Herein, we report a case of acute superior mesenteric embolism successfully treated with AngioJet hydrodynamic mechanical thrombectomy and EKOS catheter pharmacological thrombolysis. A 76-year-old man with new onset atrial fibrillation presented with abdominal pain of 48 hours duration. Subsequent contrast computed tomography scan of the abdomen revealed a filling defect in the superior mesenteric artery (SMA), suggestive of an acute embolus, which was confirmed by SMA angiogram. The AngioJet aspiration device was used for hydrodynamic suction thrombectomy. The repeat angiogram demonstrated only a partial restoration of blood flow, and thus the EKOS tissue plasminogen activator catheter was left in the SMA for continuous thrombolysis. The patient underwent continuous thrombolysis for two days, with two subsequent sessions of angiography. Thereafter, the patient improved symptomatically and serum lactate was normalized. In conclusion, the AngioJet suction thrombectomy and pharmaco-mechanical thrombolysis using the EKOS catheter is associated with minimal morbidity and can be rapidly performed. It may be used as an alternative to open surgical thrombectomy in selected cases of acute SMA embolism.

Perineal hernia after proctectomy: prevalence, risks, and management.

PURPOSE: Perineal hernias are infrequent complications of abdominoperineal operations with estimated historic prevalences (from the era where the perineal wound was left open) ranging from 0.6 to 7 percent. The purpose of this study was to identify the modern prevalence of postoperative perineal hernias, factors that may contribute to their development, and examine the methods of repair. METHODS: The Mayo Clinic patient database (1990-2000) was interrogated for the following data identifiers: incisional hernia, perineal hernia, abdominoperineal resection, proctocolectomy, and partial or total pelvic exenteration. All surviving patients were followed up to December 2005. The retrieved patient data was retrospectively analyzed. RESULTS: Of a total of 3,761 patients who underwent abdominoperineal resection (including nonrestorative proctocolectomy and pelvic exenteration) during the study period, 8 developed a perineal hernia (5 females). The median age at hernia presentation was 76 (range, 69-84) years, representing a median interval of 22 (range, 1-60) months from the original operation. All were smokers (> or =15 pack years) and five had received chemoradiotherapy for their original diagnosis. The commonest prevalence was found in patients who had undergone abdominoperineal resection (5/1,266) or pelvic exenteration (2/1,334). Only 1 of 1,161 patients developed a perineal hernia after proctocolectomy despite most being on perioperative immunosuppression for inflammatory bowel disease. Abdominal exploration and repair was performed in four patients whereas four underwent perineal repair (2 of each with mesh). None have recurred with a median follow-up of 36 (range, 6-60) months. CONCLUSIONS: Perineal hernias are rare complications of abdominoperineal surgery with a more common prevalence after cancer operations. Smoking and chemoradiotherapy, but not corticosteroid immunosuppression, may be factors. The abdominal approach has advantages over the perineal approach, but both are suitable with good medium-term results.