Yukio Kuniyoshi

Prevention of postoperative paraplegia during thoracoabdominal aortic surgery

BACKGROUND We present data showing the impact of sequential multisegmental aortic clamping accompanied by reimplantation of as many segmental arteries as possible on the prevention of postoperative paraplegia or paraparesis during thoracoabdominal aortic graft replacement. METHODS Since 1987 we have performed graft replacements in 51 individuals undergoing thoracoabdominal aortic surgery using the technique of normothermic partial bypass with sequential multisegmental aortic clamping. The procedure was performed emergently in 10 patients and electively in 41 patients. The patients ranged in age from 22 to 82 years (mean, 57.6 +/- 13.8 years). Indications for surgery included dissecting thoracoabdominal aortic aneurysm (n = 19) and nondissecting thoracoabdominal aortic aneurysm (n = 32). The extent of aneurysm was Crawford type I in 19 patients, type II in 7 patients, type III in 12 patients, and type IV in 13 patients. Along the entire extent of aneurysm to be replaced, we reimplanted as many of the patent segmental arteries as feasible. RESULTS Five patients died during hospitalization, for an in-hospital mortality rate of 9.8%. The number of aortic clampings per patient ranged from one to five (median, three). A total of 124 segmental arteries were reimplanted in 44 (86.3%) of 51 patients. Of the 124 arteries, 90 (72.6%) were distributed between T9 and L2. Postoperative paraplegia or paraparesis did not develop in any of the patients. CONCLUSIONS Our results demonstrate that extensive reimplantation of segmental arteries using sequential multisegmental aortic clamping, accompanied by adequate intraoperative distal aortic perfusion, is effective in preventing spinal cord ischemia.

Upregulation of Hypoxia-Inducible Factor-1α mRNA and its Clinical Significance in Non-small Cell Lung Cancer

Background: Hypoxia-inducible factor 1α (HIF-1α) is a transcription factor that plays an important role in tumor growth by regulating the energy metabolism and angiogenesis. We herein investigated the mRNA expression level of HIF-1α in non-small cell lung cancer (NSCLC) tissues to clarify the impact on the clinical aspects of NSCLC patients. Experimental Design: HIF-1α mRNA derived from either a tumor or an adjacent lung tissue was quantified using quantitative reverse transcription polymerase chain reaction in 66 patients with NSCLC. The relationship between the mRNA expression level of HIF-1α and clinicopathological factors was investigated. Results: The expression level of HIF-1α mRNA, which correlated with its protein level, was significantly higher in tumor tissue than in the corresponding nontumor-bearing lung tissue (4.22 × 104 ± 4.99 × 104 versus 1.24 × 104 ± 1.15 × 104; p < 0.001). The level of HIF-1α mRNA showed a significantly positive correlation with the mRNA levels of vascular endothelial growth factor and type II hexokinase in tumors (p < 0.0001 for each). In node-negative patients, high expression levels of HIF-1α mRNA in tumors were associated with a poor prognosis (p = 0.0401), but not in the node-positive cases. Conclusion: The expression of HIF-1α mRNA is associated with disease progression in NSCLC tissues, and is expected as a biomarker or therapeutic target.

Long-Term Results of Microscopic Lymphatic Vessel-Isolated Vein Anastomosis for Secondary Lymphedema of the Lower Extremities

PurposeTo evaluate the effectiveness of microscopic lymphatic vessel-isolated vein anastomosis in patients with secondary obstructive lymphedema of a lower extremity, refractory to nonoperative management.MethodsNine women suffered from nonpitting edema of one or both legs (11 limbs) after radical hysterectomy with postoperative irradiation for uterine cancer. The indications for this operation were repeated cellulitis and severe nonpitting edema impairing limb function. Under microscopy of 3.2 on average, the identified lymphatic vessels were anastomosed to an isolated saphenous vein using the pull-through technique with modifications.ResultsThe follow-up period ranged from 21 to 87 months and the operation achieved excellent reduction, of more than 5 cm, in six limbs; good reduction, of 2–5 cm, in two limbs; and poor reduction, of less than 2 cm, in three limbs. The frequency of cellulitis decreased from 2.4 infections per patient per year to 0.2 infections per patient per year.ConclusionThese results show that microscopic lymphatic vessel-isolated vein anastomosis is a minimally invasive operation, with good long-term effects, making it the treatment of choice for intractable secondary lymphedema of the lower extremities refractory to physiotherapy.

Graft for Mycotic Thoracic Aortic Aneurysm: Omental Wrapping to Prevent Infection

Nine cases of mycotic thoracic aortic aneurysm were treated surgically between July 1995 and March 2003. The aneurysms were located in the ascending aorta in 1 patient, the descending thoracic aorta in 5, and the thoracoabdominal aorta in 3. Preoperatively, 3 patients were in shock due to rupture of the aneurysm. All patients underwent aneurysmectomy and in-situ graft placement. In 5 patients, the graft was covered with a pedicled omental flap to prevent postoperative graft infection. There were 2 hospital deaths: one patient died of multi-organ failure, and the other died from intrathoracic bleeding. After discharge, one patient died from intrathoracic bleeding 3 months after surgery. These 3 patients had not received omental wrapping. Postoperative graft infection did not occur in the 6 surviving patients during a mean follow-up period of 4.0 ± 3.1 years. It was concluded that covering the prosthetic graft with a pedicled omental flap may help prevent postoperative graft infection and improve the surgical results.

Pannus formation in aortic valve prostheses in the late postoperative period

We present three patients who underwent repeat aortic valve replacement for prosthetic valve dysfunction caused by tissue ingrowth in the late postoperative period. These patients (three women aged 48–51 years, mean 49.3 ± 1.53 years) underwent operations for restriction of prosthetic valve leaflet movement by pannus in the left ventricular outflow tract. The interval from the previous operation ranged from 8.0 to 9.6 years (mean 9.6 ± 2.0 years). The symptoms of the patients were New York Heart Association functional class I, II, and IV in one patient each. Diagnosis was made by cinefluoroscopy in two patients and aortography in one patient. The operative procedures consisted of aortic valve replacement (n = 1) and aortic valve replacement with mitral valve replacement (n = 2). Pannus was found at the left ventricular aspect of the prosthetic valve in all patients. In two patients, the pannus directly restricted movement of the leaflet and also severely narrowed the inflow orifice of the prosthetic valve. In the other patient, the pannus had grown at a distance of 7 mm from the valve and narrowed the left ventricular outflow tract circularly. The postoperative course was uneventful and all three patients were discharged in a good condition. One patient died of pneumonia 8 months after surgery and the other two patients have remained well and have been followed up for one and a half years. In conclusion, there may be a discrepancy between the clinical symptoms and the grade of subvalvular stenosis caused by pannus. Therefore, it is essential for satisfactory operative results that early diagnosis be made by various means.

Radical open endvenectomy with autologous pericardial patch graft for correction of Budd-Chiari syndrome.

A surgical technique for the treatment of Budd-Chiari syndrome associated with vena caval obstruction has been devised. The occluded hepatic vena cava and hepatic veins were reconstructed by open endvenectomy, using an autologous pericardial patch graft and a femorofemoral bypass technique. The hepatic artery and portal vein were not controlled with vascular clamps during the surgery. Between 1979 and 1994, 29 patients were treated using this technique and achieved good results. All the patients did well with good function of the reconstructed vena cava and of the hepatic veins, and showed acceptable reduction of symptoms caused by portal hypertension and caval stagnation.

The impact of preoperative identification of the Adamkiewicz artery on descending and thoracoabdominal aortic repair

OBJECTIVE To investigate the impact of preoperative identification of the Adamkiewicz artery (AKA) on prevention of spinal cord injury (SCI) through the multicenter Japanese Study of Spinal Cord Protection in Descending and Thoracoabdominal Aortic Repair (JASPAR) registry. METHODS Between January 2000 and October 2011, 2435 descending/thoracoabdominal aortic repairs were performed, including 1998 elective repairs and 437 urgent repairs, in 14 major centers in Japan. The mean patient age was 67 ± 13 years, and 74.2% were males. There were 1471 open repairs (ORs), including 748 descending and 137 thoracoabdominal extent [Ex] I, 136 Ex II, 194 Ex III, 115 Ex IV, and 138 Ex V, and 964 endovascular repairs (EVRs). Of the 2435 patients, 1252 (51%) underwent preoperative magnetic resonance or computed tomography angiography to identify the AKA. RESULTS The AKA was identified in 1096 of the 1252 patients who underwent preoperative imaging (87.6%). Hospital mortality was 9.2% (n = 136) in those who underwent OR and 6.4% (n = 62) in those who underwent EVR. The incidence of SCI was 7.3% in the OR group (descending, 4.2%; Ex I, 9.4%; Ex II, 14.0%; Ex III, 14.4%; Ex IV, 4.2 %; Ex V, 7.2%) and 2.9% in the EVR group. The risk factors for SCI in ORs were advanced age, extended repair, emergency, and occluded bilateral hypogastric arteries. In ORs of the aortic segment involving the AKA, having no AKA reconstruction was a significant risk factor for SCI (odds ratio, 2.79, 95% confidence interval, 1.14-6.79; P = .024). CONCLUSIONS In descending/thoracoabdominal aortic repairs, preoperative AKA identification with its adequate reconstruction or preservation, especially, in ORs of aortic pathologies involving the AKA, would be a useful adjunct for more secure spinal cord protection.

Infectious mediastinitis after cardiovascular surgery: role of computed tomography

PurposeThe aim of this study was to evaluate the effectiveness of computed tomography (CT) findings in the diagnosis of mediastinitis after cardiovascular surgery with median sternotomy.Material and methodsA total of 122 patients were divided into two groups: the early group (≤21 days after surgery) and the late group (>21 days after surgery). Among them, six patients were ultimately diagnosed with infectious mediastinitis. CT findings in each patient were evaluated. Mediastinal fluid collections or free gas bubbles were regarded as the primary findings of mediastinitis.ResultsIn the early group, sensitivity and specificity of the primary CT findings were 100% and 39%, respectively. In the late group, the sensitivity was 100% and the specificity 85%. Mediastinal fluid collections were observed in all six patients with mediastinitis.ConclusionMediastinal fluid collections or free gas bubbles are not specific during the early postoperative period. However, after 2 21 days, these observations could be indicative of mediastinitis.

Potential role of omental wrapping to prevent infection after treatment for infectious thoracic aortic aneurysms

OBJECTIVES Postoperative infection control is one of the most important issues for infected aortic aneurysms, and the methods of preventing recurrent infection remain controversial. We previously reported that omental flaps could prevent or reduce the occurrence of infection after implanting an artificial aortic graft. However, the long-term outcomes of this strategy are unknown. We used imaging modalities to evaluate whether wrapping prosthetic grafts with omentum prevents postoperative graft infection over the long-term. METHODS We surgically treated 521 patients with thoracic aortic aneurysm (TAA) at our hospital between July 1995 and May 2012. Of these, 22 (3.9%) (male, n = 17; mean age, 68.2 ± 11.4 years) had infectious TAA. All infectious aneurysms were resected, all patients received in-situ grafts and 16 grafts were wrapped with omentum. We followed up all survivors annually using computed tomography. We also used angiography to investigate blood circulation in omental flaps over the long-term. RESULTS Five patients died in-hospital (operative mortality, 26.3%). The operative mortality rates of patients with and without omental wrapping were 12.5 and 50.0%, respectively (P = 0.06, NS), and the 5-year event-free survival rates were 84.6 and 33.3% (P = 0.025), respectively. Omental flaps around prosthetic grafts and their blood circulation were well-preserved over the long-term. CONCLUSIONS Wrapping implanted artificial aortic grafts with omental flaps could prevent or reduce the occurrence of subsequent infection. Furthermore, blood circulation in the flaps must be well-preserved to improve the long-term outcomes.

A three-decade experience of radical open endvenectomy with pericardial patch graft for correction of Budd-Chiari syndrome

BACKGROUND We previously reported the value of our operative procedure for Budd-Chiari syndrome (BCS) that comprised reconstruction of the occluded or severely stenosed inferior vena cava (IVC) using an autologous pericardium patch and reopening as many occluded hepatic veins as possible. Here, we present the long-term durability and efficacy of the autologous pericardium patch for reconstruction of the IVC in BCS. METHODS We retrospectively analyzed a series of 53 consecutive patients (mean age, 48.4 +/- 12.8 years; range, 24-76 years; 34 men) who underwent surgical treatment for BCS at our institution from 1979 to 2008. Patency of the IVC and hepatic veins was examined by venography at discharge. Patients attended an outpatient clinic every 1 or 2 months for follow-up. The reconstructed IVC was evaluated by enhanced computed tomography every 1 or 2 years. RESULTS Two in-hospital (operative mortality, 3.7%) and 15 late deaths occurred. During a mean follow-up of 7.6 +/- 6.5 years (range, 0.08-24.1 years), the reconstructed IVC became totally obstructed in three patients, of whom two underwent reoperation, and severely stenosed in two patients, who required percutaneous transvenous balloon venoplasty (PTV). The 5- and 10-year patency rates without reoperation or PTV for the reconstructed IVC were 90.5% and 84.3%, respectively. The cumulative 5- and 10-year survival rates were 89.8% and 70.7%, respectively. CONCLUSION The autologous pericardium patch is effective and durable for reconstructing a diseased IVC in BCS.