Fumiaki Shikata

Does the off-pump Fontan procedure ameliorate the volume and duration of pleural and peritoneal effusions?

OBJECTIVE We initiated an off-pump Fontan procedure by using temporary bypass from the inferior vena cava to the atrium and advanced the procedure in selected patients by simply cross-clamping the inferior vena cava. We aimed to investigate whether the off-pump Fontan procedure could ameliorate the volume and duration of pleural and peritoneal effusion. METHODS We retrospectively reviewed 74 patients (aged <4 years) who underwent Fontan completion between January 2001 and December 2006. The patients were classified into the following two groups: a cardiopulmonary bypass group in which cardiopulmonary bypass was required (n=27) and an off-pump group in which the procedure was completed without the use of cardiopulmonary bypass (n=47). A propensity score was used to control the treatment selection bias for the use of cardiopulmonary bypass. Fourteen patients from each group were successfully matched. Both bilateral pleural and peritoneal drainage tubes were placed in all the patients. The total volume of the effusion was measured at 6, 12, 24, 48, and 72h postoperatively and was corrected for body weight (kg) and intervals (h). RESULTS Significantly reduced effusion (ml/kg/h) was noted in the off-pump group compared to the cardiopulmonary bypass group at 12h (cardiopulmonary bypass group, 8.6 [4.8-11.5]; off-pump group, 2.5 [1.2-5.4]; p=0.006) and at 48h (cardiopulmonary bypass group, 6.1 [2.6-9.9]; off-pump group, 1.4 [0.9-3.1]; p=0.008). CONCLUSIONS The off-pump Fontan procedure may reduce the volume of postoperative pleural and peritoneal effusion.

Subendocardial contractile impairment in chronic ischemic myocardium: assessment by strain analysis of 3T tagged CMR

BackgroundThe purpose of this study was to quantify myocardial strain on the subendocardial and epicardial layers of the left ventricle (LV) using tagged cardiovascular magnetic resonance (CMR) and to investigate the transmural degree of contractile impairment in the chronic ischemic myocardium.Methods3T tagged CMR was performed at rest in 12 patients with severe coronary artery disease who had been scheduled for coronary artery bypass grafting. Circumferential strain (C-strain) at end-systole on subendocardial and epicardial layers was measured using the short-axis tagged images of the LV and available software (Intag; Osirix). The myocardial segment was divided into stenotic and non-stenotic segments by invasive coronary angiography, and ischemic and non-ischemic segments by stress myocardial perfusion scintigraphy. The difference in C-strain between the two groups was analyzed using the Mann-Whitney U-test. The diagnostic capability of C-strain was analyzed using receiver operating characteristics analysis.ResultsThe absolute subendocardial C-strain was significantly lower for stenotic (-7.5 ± 12.6%) than non-stenotic segment (-18.8 ± 10.2%, p < 0.0001). There was no difference in epicardial C-strain between the two groups. Use of cutoff thresholds for subendocardial C-strain differentiated stenotic segments from non-stenotic segments with a sensitivity of 77%, a specificity of 70%, and areas under the curve (AUC) of 0.76. The absolute subendocardial C-strain was significantly lower for ischemic (-6.7 ± 13.1%) than non-ischemic segments (-21.6 ± 7.0%, p < 0.0001). The absolute epicardial C-strain was also significantly lower for ischemic (-5.1 ± 7.8%) than non-ischemic segments (-9.6 ± 9.1%, p < 0.05). Use of cutoff thresholds for subendocardial C-strain differentiated ischemic segments from non-ischemic segments with sensitivities of 86%, specificities of 84%, and AUC of 0.86.ConclusionsAnalysis of tagged CMR can non-invasively demonstrate predominant impairment of subendocardial strain in the chronic ischemic myocardium at rest.

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.

Prevalence of periodontitis and optimal timing of dental treatment in patients undergoing heart valve surgery

We investigated the prevalence, risk factors, and optimal timing of treatment for advanced periodontitis in patients undergoing elective heart valve surgery. Dental examinations were given to 209 patients (aged 65 ± 10 years) scheduled for valve surgery. Patients with no or mild periodontitis were assigned as controls (n = 105). Patients with advanced periodontitis underwent tooth extraction and curettage (n = 104), 68 of whom underwent tooth extraction within two weeks (short wait) and 36 of whom underwent extraction longer than two weeks, before surgery. The three groups (control, short, and long wait) were similar in age, gender, diseased valve, and type of surgery received. The average number of teeth extracted was 2.3 ± 2.3. In both univariate and multivariate analysis, risk factors for advanced periodontitis were history of smoking and heart failure. No complications arose from the extractions. Length of postoperative hospital stay, intrafebrile days, white blood cell count and serum C-reactive protein (assessed at postoperative days 1, 3 and 7) were similar among the three groups. During the mean follow-up period of 60 ± 16 months, no patient developed prosthetic valve endocarditis, and there were no postoperative deaths. In conclusion, we found no evidence that receipt and timing of dental treatment affected surgical success rates and postoperative course.

Pathophysiology of Lung Injury Induced by Common Bile Duct Ligation in Mice

Background Liver dysfunction and cirrhosis affect vasculature in several organ systems and cause impairment of organ functions, thereby increasing morbidity and mortality. Establishment of a mouse model of hepatopulmonary syndrome (HPS) would provide greater insights into the genetic basis of the disease. Our objectives were to establish a mouse model of lung injury after common bile duct ligation (CBDL) and to investigate pulmonary pathogenesis for application in future therapeutic approaches. Methods Eight-week-old Balb/c mice were subjected to CBDL. Immunohistochemical analyses and real-time quantitative reverse transcriptional polymerase chain reaction were performed on pulmonary tissues. The presence of HPS markers was detected by western blot and microarray analyses. Results We observed extensive proliferation of CD31-positive pulmonary vascular endothelial cells at 2 weeks after CBDL and identified 10 upregulated and 9 down-regulated proteins that were associated with angiogenesis. TNF-α and MMP-9 were highly expressed at 3 weeks after CBDL and were less expressed in the lungs of the control group. Conclusions We constructed a mouse lung injury model by using CBDL. Contrary to our expectation, lung pathology in our mouse model exhibited differences from that of rat models, and the mechanisms responsible for these differences are unknown. This phenomenon may be explained by contrasting processes related to TNF induction of angiogenic signaling pathways in the inflammatory phase. Thus, we suggest that our mouse model can be applied to pulmonary pathological analyses in the inflammatory phase, i.e., to systemic inflammatory response syndrome, acute lung injury, and multiple organ dysfunction syndrome.

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

BACKGROUND Multidetector-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. METHODS We 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. RESULTS Overall 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). CONCLUSIONS Our 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.

Pseudoaneurysm in the Left Groin due to Ruptured Knitted Dacron Graft

An 82-year-old man was admitted to our institution with a painful pulsating mass in the left groin. He had undergone bypass surgery with a bifurcated Cooley double velour knitted Dacron graft to treat aorto-iliac occlusive disease 21 years previously. Computed tomography demonstrated a 35-mm pseudoaneurysm near the distal anastomosis site of the graft. Opening the aneurysm revealed that the graft was disrupted along the guideline. We resected the aneurysm and interposed an expanded polytetrafluoroethylene (ePTFE) graft. Vascular surgeons should consider that grafts can fail in patients with long-term prosthetic grafts.