Hiroshi Imagawa

Transient ischemia-induced paresis and complete paraplegia displayed distinct reactions of microglia and macrophages

In this study, we perform a detailed analysis of the microglial and macrophage responses in a model of spinal cord ischemia and reperfusion (SCI/R) injury in Wistar rats. The rats underwent occlusion across the descending aorta for 13min, causing paraplegia or paresis of varying severity. They were divided into four groups based on neurological assessment: sham, mild paresis, moderate paresis, and severe (complete) paraplegia. To examine the origin of microglia and macrophages in the ischemic lesion, bone marrow from rats expressing green fluorescent protein (GFP) was transplanted into test subjects one month before performing SCI/R. Many GFP(+)/CD68(+) microglia and macrophages were present 7d after SCI/R. Resident (GFP(-)/Iba1(+)/CD68(-)) microglia and bone marrow-derived macrophages (BMDMs; GFP(+)/Iba1(+)/CD68(+)) colocalized in the mild group 7d after SCI/R. In the moderate group, BMDMs outnumbered resident microglia. A greater accumulation of BMDMs expressing insulin-like growth factor-1 (IGF-1) was observed in lesions in the severe group, relative to the moderate group. BMDMs in the severe group strongly expressed tumor necrosis factor α, interleukin-1β, and inducible nitric oxide synthase, in addition to IGF-1. A robust accumulation of BMDMs occupying the entire ischemic gray matter was observed only in the severe group. These results demonstrate that the magnitude of the microglial and BMDM responses varies considerably, and that it correlates with the severity of the neurological dysfunction. Remarkably, BMDMs appear to have a beneficial effect on the spinal cord in paresis. In contrast, BMDMs seem to exhibit both beneficial and harmful effects in severe paraplegia.

Capillary Leakage in Cardiac Surgery with Cardiopulmonary Bypass

Cardiopulmonary bypass causes a systemic inflammatory response, which can lead to capillary leak syndrome. In 15 adults undergoing elective cardiac surgery with cardiopulmonary bypass, we determined the volume and peak time of capillary leakage from the measurements of extracellular fluid volume and circulating blood volume taken preoperatively, at various intervals up to 24 hours after surgery, and on the 7th postoperative day. Extracellular fluid volume rose from 15.5 ± 2.7 Lpreoperatively to a peak 4 hours after surgery of 18.3 ± 3.2 L and remained elevated at 24 hours. Circulating blood volume fell from 4.10 ± 0.68 L preoperatively to 3.20 ± 0.58 L at the end of surgery. Fluid administered intraoperatively did not raise the circulating blood volume. Intraoperative fluid balance was positive at 2.62 ± 0.72 L but negative at all time points postoperatively. There was significant postoperative capillary leakage, increasing from 4.7% ± 2.3% of body weight at the end of surgery to a peak 4 hours later of 5.4% ± 2.0% and falling to 2.8% ± 3.3% at 24 hours. This knowledge of the pattern of change in capillary leakage after cardiac surgery with cardiopulmonary bypass might serve as a valuable guide for postoperative management.

Anomalous subaortic left brachiocephalic vein in surgical cases and literature review.

Anomalous subaortic left brachiocephalic vein (ASLBV) is a rare systemic venous anomaly. We review our experience with patients associated with ASLBV who underwent cardiac surgery at three institutions. From 1989 to 2009, the medical records of surgically treated patients with ASLBV were analyzed; the incidence of ASLBV, clinical characteristics, and associated anatomical findings were assessed. Fifteen patients had ASLBV. All ASLBVs coursed left lateral to the aortic arch, passed under the ascending aorta anterior to the central pulmonary artery, and joined the right brachiocephalic vein. Fourteen patients had congenital heart disease (CHD), and the remaining patient did not have cardiac anomalies. Its incidence was 0.57% (14 of 2,449) in patients with CHD and only 0.02% (1 of 4,805) in patients without CHD. In patients with CHD, 73.3% (11 of 15) of the patients had conotruncal cardiac anomalies such as tetralogy of Fallot, ventricular septal defect with pulmonary atresia, truncus arteriosus, and interruption of the aortic arch. Eight patients had aortic arch anomalies, including right aortic arch and cervical aortic arch. The deletion of chromosomal 22q11.2 was confirmed in two patients, and one patient was diagnosed with DiGeorge syndrome. ASLBV was clinically silent even without any surgical intervention. ASLBV is a very rare anomaly and is highly associated with conotruncal cardiac anomalies and aortic arch anomalies, including right aortic arch and cervical aortic arch. Preoperative diagnosis is important when any surgical interventions are intended, especially, in patients with conotruncal cardiac anomalies. Clin. Anat. 23:950–955, 2010.

Two-Patch Technique for Postinfarction Inferoposterior Ventricular Septal Defect

We describe 4 patients with postinfarction inferoposterior ventricular septal defect treated by the two-patch technique for infarct exclusion operation. The ventricular septal defects were closed using two bovine pericardial patches as follows. The septal patch was sutured to the noninfarcted septum covering the defect, and the free wall patch was sutured to the endocardium adjacent to the posterior papillary muscle. The two patches were sutured together and all infarcted areas were excluded from the left ventricular pressure. This technique seems to be useful in specific circumstances, such as when the ventricular defect is located in the inferoposterior septum.

Migration of Distal Ventriculoperitoneal Shunt Catheter into the Pulmonary Artery

A 50-year-old man presented with an abdominal bulge 2 years after receiving a ventriculoperitoneal (VP) shunt for hydrocephalus. Chest radiography revealed that the peritoneal end of the catheter had migrated into the right pulmonary artery. Exploration through a small neck incision revealed that the shunt catheter had entered the internal jugular vein. The catheter was extracted and positioned in the subcutaneous space in preparation for reimplantation. This type of shunt migration is quite unusual, but it could cause lethal pulmonary infarction or arrhythmia. Follow-up radiography should be scheduled to detect such complications.

Regional myocardial blood flow measured by stress multidetector computed tomography as a predictor of recovery of left ventricular function after coronary artery bypass grafting

BACKGROUNDnMultidetector-row computed tomography (MDCT) applications have expanded to evaluation of myocardial blood flow (MBF) and viability. We quantified regional MBF pre- and post-coronary artery bypass grafting (CABG) using adenosine stress and cardiac 64-MDCT, and investigated whether the results predict MBF and left ventricular (LV) function recovery after CABG.nnnMETHODSnWe studied 321 regions in 19 CABG patients who underwent adenosine stress 64-row MDCT perfusion imaging and cine magnetic resonance imaging pre- and post-CABG. Myocardial blood flow was estimated from linear regression equation slopes using Patlak plot analyses and compared with LV function by measuring wall thickening (%WT) using cine magnetic resonance imaging.nnnRESULTSnOverall mean MBFs were 1.39 +/- 0.49 and 1.95 +/- 0.49 mL/(g min) pre- and post-CABG (P < .0001). Myocardial blood flow in revascularized areas increased significantly (pre-CABG 1.18 +/- 0.45, post-CABG 1.99 +/- 0.66 mL/[g min], P < .001), whereas nonischemic areas showed no difference (1.79 +/- 0.70 and 1.97 +/- 0.46 mL/[g min], P = .14). Revascularized areas with preoperative MBF > or = 0.9 mL/(g min) showed significantly greater MBF improvement than those with preoperative MBF <0.9 mL/(g min) (P = .04). In patients with preoperative LV dysfunction (ejection fraction <40%), %WT in revascularized areas with pre-CABG MBF > or = 0.9 mL/(g min) improved significantly after CABG (pre-%WT 40.9 +/- 22.9, post-%WT 52.8 +/- 20.6, P = .03) versus those with pre-CABG MBF <0.9 mL/(g min) (pre-%WT 53.2 +/- 35.5, post-%WT 42.5 +/- 17.0, P = .40).nnnCONCLUSIONSnOur results demonstrated more significantly increased MBF post-CABG than pre-CABG, particularly in revascularized areas. Regional MBF before CABG may predict MBF and LV function recovery, in the short term, after CABG.

Pitavastatin Prevents Bacterial Translocation after Nonpulsatile/Low-Pressure Blood Flow in Early Atherosclerotic Rat: Inhibition of Small Intestine Inducible Nitric Oxide Synthase

Background: Cardiopulmonary bypass decreases intestinal mucosal blood flow because of nonpulsatile and low-pressure blood flow resulting in bacterial translocation (BT) and atherosclerosis also has peripheral blood flow deficiency. The risk of nonpulsatile and low-pressure blood flow for atherosclerotic animals and the effect of statin administration, which has pleiotropic effects, were studied. Methods: Wistar rats were divided into four groups: group N (normal diet), group C (high-cholesterol diet), group S (group C plus pitavastatin therapy), and group I [group C plus inducible nitric oxide (iNOS) inhibitor therapy]. First of all, vascular responses were measured. Then the rats underwent nonpulsatile/low-pressure blood flow in the intestine, and the serum peptidoglycan concentration as a parameter of BT, the small intestinal PO2 ratio (intestinal PO2/PaO2) as a parameter of mucosal blood flow, and NO concentrations were measured before surgery (T0), at the end of 90 min of stenosis (T1), and 90 min after the release of stenosis (T2). Immunostaining for nitrotyrosine was also performed at T2. Results: Group C had vascular endothelial dysfunction without histological changes, which indicated early atherosclerosis. The serum peptidoglycan concentration increased significantly at T2 only in group C. The intestinal PO2 ratio was decreased at T1 in all the groups, and retuned to baseline at T2 in group N and group S, but not in group C or group I. Jejunal NO only in group C was significantly higher at all time points and ileal NO production at T1 and T2. There tended to be a positive stain for nitrotyrosine along the mucosal epithelium in group C. Conclusion: In the setting of early atherosclerosis, intestinal blood flow does not only improve after nonpulsatile/low-pressure blood flow but causes BT because of a large amount of NO from high enzymatic intestinal iNOS activity, and pitavastatin treatment can prevent BT by improving both issues.

Fading Out Dip-and-Plateau Pattern of Right Ventricular Pressure in Constrictive Pericarditis

A 64-year-old woman presented with general fatigue and abdominal distension of several months duration. She had no history of cardiac surgery, mediastinal irradiation, or infectious diseases. Computed tomography revealed constrictive pericarditis with massive ascites and pleural effusion. Surgical therapy was indicated. Doppler sonography of the hepatic vein demonstrated a typical W-shaped pattern with reverse flow during expiration (Figure 1). Under general anesthesia, the chest was opened via a median sternotomy while right ventricular (RV) pressure was monitored with a pulmonary artery balloon catheter (780HF75, Swan-Ganz oximetry Paceport TD catheter, Edwards Lifesciences, Irvine, Calif), which was equipped with an …

Immediate localization using ultrasound-guided hookwire marking of peripheral lung tumors in the operating room.

A new method of marking peripheral lung tumors using an ultrasound-guided hookwire has been developed. The procedure was done for nine tumors taking 15-20 min for each method in the operating room; all of them had no complications. In eight cases (89%), the wire tips were shown to be located within the tumor itself or within 5 mm from the targets, close enough to support appropriate surgery. Ultrasound-guided hookwire marking of peripheral tumors can provide appropriate guidance and prove effective in immediately facilitating subsequent thoracoscopic resection.

The use of a handmade balloon-expandable covered stent for native coarctation of the aorta in an adult patient: A report of a first case in Japan

In western countries, the use of a balloon-expandable covered stent is recommended for the treatment of native coarctation of the aorta (CoA) in adult patients because endovascular bare stents cannot completely prevent complications such as aneurysms or aortic rupture. However, such a product that is appropriate and officially approved is not available in Japan. We developed and used a handmade balloon-expandable covered stent in a 32-year-old patient with native CoA and achieved a good outcome. A Palmaz-Schatz stent (XL 10-series 4010; Johnson & Johnson, Warren, NJ, USA) was covered with an Ube woven-graft (WST series; 18 mm across; Ube Junken Medical, Tokyo, Japan). Because the stent shortens when dilated, one end of the graft was firmly sutured to one end of the stent, whereas the other end of the graft was stitched loosely to the other end of the stent so that it could slide along the struts of the stent to accommodate foreshortening. After meticulous in vitro simulations, the covered stent was implanted with right ventricular overdrive pacing. No complications were observed, and the pressure gradient disappeared. These results indicate that angioplasty using a balloon-expandable covered stent is highly safe and effective for correcting native CoA in adult patients and hopefully in children.