Yusuke Shintani

Hepatocyte growth factor promotes an anti-inflammatory cytokine profile in human abdominal aortic aneurysm tissue

Abdominal aortic aneurysm (AAA) is characterized by the destruction of tissue architecture due to chronic inflammation of unknown etiology. Recent studies have indicated that control of inflammation is a promising therapeutic strategy; however, no established pharmacological intervention is currently available for AAA. We found that hepatocyte growth factor (HGF) was expressed in aneurysmal tissue, and colocalized with von Willebrand factor, the endothelial cell marker, in the most damaged part of the aneurysmal walls. In ex vivo cultures of human AAA tissue, exogenously added HGF in the presence of tumor necrosis factor-alpha (TNF-α) enhanced the secretion of anti-inflammatory cytokine interleukin-10 (IL-10) and suppressed the secretion of proinflammatory monocyte/macrophage chemotactic protein-1 (MCP-1). The angiotensin converting enzyme (ACE) inhibitors, imidaprilat and perindoprilat, enhanced the secretion of endogenous HGF, augmented the TNF-α-induced IL-10 secretion and suppressed MCP-1 secretion from AAA tissue. The ACE inhibitors also augmented the expression of HGF in the presence of bradykinin in human aortic endothelial cells in culture (HAECs). In contrast, HGF secretion was not affected by either an angiotensin II type 1 receptor (AT1) antagonist or angiotensin II in AAA tissue or in HAECs. These results suggested that angiotensin converting enzyme inhibitors may be useful in controlling chronic inflammation in AAA, partly due to their enhancement of HGF secretion.

Spontaneous Dissection of the Iliac Artery in a Patient With Fibromuscular Dysplasia

A 49-year-old man was referred to our hospital at 10 days after the onset of sudden intermittent claudication of the right lower limb and with right lower abdominal pain. Diagnosis by computed tomography scan and pelvic angiography was dissection from the common iliac artery to peripheral external iliac artery with thrombosed false lumen. Replacement of the common and external iliac artery was performed using a 10-mm Dacron prosthesis. A pathological examination of the right common iliac artery revealed an arterial disorder caused by fibromuscular dysplasia.

Prevention of Venous Thromboembolism in Thoracic and Cardiovascular Surgery

Venous thromboembolism is the most preventable illness among patients in hospital. We prepared guidelines for the prophylaxis of venous thromboembolism, based on previous experience of perioperative risk factors. The aim of this study was to evaluate the effectiveness of these guidelines. All 1,467 patients who underwent surgery for thoracic or cardiovascular disease between April 2002 and July 2004, before the prophylactic guidelines were implemented, were assigned to group A. Another 1,389 patients who had surgery between August 2004 and December 2006, after the guidelines had been implemented, formed group B. The incidences of venous thromboembolism perioperatively in the 2 groups were compared. Six (0.4%) patients in group A developed deep vein thrombosis or pulmonary embolism, whereas no patient in group B experienced thromboembolism. The difference between groups was significant, so we consider our guidelines for venous thromboembolism prevention in the perioperative period to be clinically useful.

Clinical outcome of perioperative nonpermanent vena cava filter placement in patients with deep venous thrombosis or blood stasis of the vein.

PurposeTo evaluate the recent clinical experience with nonpermanent inferior vena cava (IVC) filter placement preoperatively, especially with regard to patients who had deep venous thrombosis (DVT) due to compression by a tumor or an aneurysm.MethodsPreoperative prophylactic IVC filter placement was performed between October 2002 and March 2008 in 48 of 83 patients who underwent IVC filter placement. IVC filter placement was performed preoperatively in 35 of the 48 patients due to DVT located distally in an iliac vein or due to IVC compression by a tumor or aneurysm. This study examined the early and mid-term outcomes resulting from nonpermanent IVC filter placement.ResultsThe mean implantation period was 11.1 ± 9.3 days (range, 3–56 days). Three patients (8.6%) experienced minor complications during the IVC filter placement. A thrombus was captured in the filter in 4 patients (8.8%). One patient in whom the filter was left as a permanent filter died during the follow-up period. No patient experienced any pulmonary embolus during the follow-up period.ConclusionNonpermanent IVC filter insertion is perioperatively useful in surgical procedures that eliminate the compression of the vein by an excision of either the tumor or aneurysm compressing the vein.

Thoracic Endovascular Aortic Repair with Homemade Stent Grafts : Early and Mid-Term Outcomes

PurposeWe reviewed our experience with homemade stent grafts in the repair of a variety of thoracic aortic lesions. The objective of this study was to assess the early and mid-term outcomes of this therapy.MethodsFrom 1999 to 2007, homemade stent grafts were inserted in 88 patients with an atherosclerotic aneurysm, dissection, pseudoaneurysm, trauma, or rupture in the thoracic aorta. The endoprostheses were stainless steel Z-stents covered by a polyester graft, and were custom-designed for each patient.ResultsPlacement of stent grafts was technically successful in 81 of the 88 patients (92%). Within 30 days after treatment, 3 patients died, 3 had a cerebral infarction, and 3 had onset of paraplegia or paraparesis. Primary endoleaks were observed in 8 patients (9%). During the mean follow-up period of 32 ± 26 months, 7 patients had persistent endoleaks and 7 had stent-graft migration. The aneurysm-related mortality rate was 7%. The rate of freedom from open-surgery conversion at 32 months was 89.0%.ConclusionsOur early experience with elective and emergency thoracic endovascular aortic repair using homemade stent grafts provided therapeutic benefits to high-risk patients. Endoleaks and stent-graft migrations were the factors most commonly responsible for secondary intervention in the mid-term period. Careful follow-up of patients treated with this approach is needed to avoid major complications in the long term.

Non-permanent Inferior Vena Cava Filters for Prophylaxis and Treatment of Lower Limb Venous Thromboembolisme

Objectives: The purpose of this study was to evaluate and compare our recent clinical experience with temporary inferior vena cava (IVC) filters (TF) and retrievable IVC filters (RF). Materials and methods: Patients who received TF or RF implantation between October 2002 and May 2009 were studied. The early clinical outcomes between the 2 groups were compared. Results: Nonpermanent IVC filters were placed in 119 patients (34 in TF and 85 in RF). Retrieval of RF and removal of TF were successful in 98.7% and 100%, respectively. The incidence of filter-related complications for TF was significantly higher than for RF (26.5% vs 3.5%; P = .0004). However, no symptomatic pulmonary embolism (PE) was observed during filter placement. Conclusion: TF and RF provided similar protection from PE. We prefer RF because they can be left in permanently if it is impossible to remove or retrieve the filter for some reason.

Inflammatory reaction of a pericardial foreign body after cardiac surgery

A 74-year-old man, who had undergone an aortic valve replacement for aortic regurgitation at the age of 57 and atrioventricular node ablation for refractory paroxysmal atrial flutter and concurrent pacemaker implantation at the age of 65, was admitted to our hospital due to fatigue and exertional dyspnea. He was diagnosed as constrictive pericarditis by cardiac catheterization, which has shown a dip-and-plateau sign of ventricular diastolic pressure. Subsequently, pericardiectomy was performed. At postoperative period, however, elevated levels of C-reactive protein (CRP) were sustained (4.5 to 12.0 mg/dL) and his symptoms were not improved. Whereas there was an unclear lesion evident on the chest X-ray as it overlapped the cardiac silhouette (Figure 1A), the computed tomography (CT) scan and three-dimensional (3D) reconstruction revealed a characteristic whirl-like radio-opaque foreign body, suggesting the retained surgical gauze pad (Figure 1B, C, and F: yellow arrows; Supplementary Data). At the same location, 18F-fluorodeoxyglucose (FDG)-positron emission tomography combined with CT or 3D-CT demonstrated intense FDG uptake in the foreign body, indicating an inflammatory reaction (Figure 1D, E, and G: red arrows; Supplementary Data), which we decided to surgically remove. The foreign body was identified as gauze without abscess (Figure 1H). After removal of the foreign body, his symptoms were diminished and CRP levels decreased from 12.0 to 2.6 mg/dL. The patient was discharged without other events. Cotton gauze may lead to exudative inflammatory reaction and have catastrophic implications for patient.

Abdominal Aortic Aneurysm Caused by Aortic Fibromuscular Dysplasia: A Case Report

Fibromuscular dysplasia (FMD) mainly develops in medium-sized arteries, including renal, extracranial, and extremity arteries, but it rarely causes abdominal aortic aneurysm (AAA). A 69-year-old woman with AAA diagnosed on ultrasonography by a home doctor visited our hospital. Contrast-enhanced computed tomography revealed a saccular aneurysm of terminal abdominal aorta. We performed abdominal aortic replacement and resected the section with aneurysm. Pathological examination of the wall tissue of the resected aneurysm revealed findings that are consistent with FMD. We report this case of AAA caused by aortic FMD because of its rarity.