Safety of warfarin therapy in chronic hemodialysis patients: a prospective cohort study

Background

We conducted a multicenter prospective cohort study to assess the safety of warfarin therapy in Japanese hemodialysis (HD) patients.

Methods

Chronic HD patients on warfarin therapy (warfarin users) were recruited from 111 HD centers in Japan. Two dialysis-vintage-matched warfarin non-users (non-users) were selected from the same HD center as each warfarin user. Clinical data were collected upon registration and every 12 months thereafter for up to 36 months.

Results

The final cohort consisted of 365 warfarin users and 692 non-users and was followed for an average of 27.7 months. The mean age of warfarin users (68.8 ± 10.6 years) was significantly higher than that of non-users (66.9 ± 11.0 years, p < 0.001). The analyses by multivariate Cox proportional-hazard models showed that the age [hazard ratio (HR) = 1.07 for each 1-year increase, 95 % confidence interval (CI) 1.05–1.08, p < 0.001] was significantly associated with the death from any cause, but warfarin use (1.08, CI 0.75–1.57, p = 0.68) was not when being adjusted for sex, diabetes mellitus, antiplatelet use, and atrial fibrillation. The risk of composite events, which included death from any cause, stroke, cardiovascular disease, and peripheral arterial disease, was also associated with age but was not associated with warfarin use.

Conclusion

The results of this study suggested that warfarin use by HD patients might not be harmful in chronic state, while the safety for the initiation of warfarin therapy in HD patients remained to be determined.

     

Is left upper lobectomy for lung cancer a risk factor for cerebral infarction?

Purpose

Cerebral infarction is a rare complication of lung resection that can result in severe sequelae. Our aim was to investigate the characteristics of patients who suffer from cerebral infarction after surgery for lung cancer.

Methods

We retrospectively reviewed all patients who underwent resection of at least a single lobe for lung cancer at our institution between January 2008 and October 2013. We compared the patients who presented with cerebral infarction with those patients who did not within 30 days of surgery.

Results

A total of 562 patients underwent surgery, with five males and one female subsequently experiencing cerebral infarction. Five patients underwent left upper lobectomy and one underwent left lower lobectomy. Patient age, sex, body mass index, smoking index, and operative time were not significantly different between the six patients with postoperative cerebral infarction and the other 556 patients; only the type of operative procedure was significantly different (p < 0.001). Contrast-enhanced computed tomography revealed thrombosis in the stump of the left superior pulmonary vein in patients with postoperative cerebral infarction.

Conclusions

Cerebral infarction occurs at a high frequency in patients who undergo left upper lobectomy for lung cancer. Thrombosis in the left superior pulmonary-vein stump might cause cerebral infarction.

     

Intracranial Distribution of Intravenously Administered Gadolinium-based Contrast Agent over a Period of 24 Hours: Evaluation with 3D-real IR Imaging and MR Fingerprinting

Purpose:To evaluate the feasibility for the detection of slight contrast effects after intravenous administration of single dose gadolinium-based contrast agent (IV-SD-GBCA), the time course of the GBCA distribution up to 24 h was examined in various fluid spaces and brain parenchyma using 3D-real IR imaging and MR fingerprinting (MRF).Methods:Twenty-four patients with a suspicion of endolymphatic hydrops were scanned at pre-administration and at 10 min, 4 and 24 h post-IV-SD-GBCA. 3D-real IR images and MRF at the level of the internal auditory canal were obtained. The signal intensity on the 3D-real IR image of the cerebrospinal fluid (CSF) in the cerebellopontine angle cistern (CPA), Sylvian fissure (Syl), lateral ventricle (LV), and cochlear perilymph (CPL) was measured. The T₁ and T₂ values of cerebellar gray (GM) and white matter (WM) were measured using MRF. Each averaged value at the various time points was compared using an analysis of variance.Results:The signal intensity on the 3D-real IR image in each CSF region peaked at 4 h, and was decreased significantly by 24 h (P < 0.05). All patients had a maximum signal intensity at 4 h in the CPA, and Syl. The mean CPL signal intensity peaked at 4 h and decreased significantly by 24 h (P < 0.05). All patients but two had a maximum signal intensity at 4 h. Regarding the T₁ value in the cerebellar WM and GM, the T₁ value at 10 min post-IV-GBCA was significantly decreased compared to the pre-contrast scan, but no significant difference was observed at the other time points. There was no significant change in T₂ in the gray or white matter at any of the time points.Conclusion:Time course of GBCA after IV-SD-GBCA could be evaluated by 3D-real IR imaging in CSF spaces and in the brain by MRF.     

Schwannoma in the crural cistern removed without permanent functional deficits--case report

A 33-year-old male presented with a rare intracranial oculomotor schwannoma not associated with neurofibromatosis manifesting as an 8-month history of right oculomotor nerve paresis. Neuroimaging examinations revealed a 4-cm mass in the right crural cistern. The tumor was totally removed. The right oculomotor nerve paresis resolved 7 months after surgery. Removal of the oculomotor or trochlear schwannoma usually results in parent nerve paresis, but subcapsular tumor resection in our case probably allowed complete recovery of the nerve function.     

A case of the development of cavum vergae after head trauma

We report a case of the development of cavum septi pellucidi and cavum Vergae after head trauma in a 29-year-old female patient. After the accident, cavum septi pellucidi and cavum Vergae gradually expanded. Using magnetic resonance imaging, we followed up the patient for 33 months after the head trauma. Preoperatively, metrizamide CT cisternography was performed in order to investigate CSF flow between the cavum septi pellucidi/cavum Vergae and the subarachnoid space. Using neuroendoscopy, we succeeded in opening the wall of the cavum septi pellucidi via anterior horn of the right lateral ventricle. Cystography was performed during the operation. The volume of the cavum septi pellucidi/cavum Vergae decreased remarkably. In this case, our CSF flow studies revealed that CSF flowed into the posterior part of the cavum Vergae from the third ventricle and did not flow backward to the third ventricle. Therefore, we considered that the development of cavum septi pellucidi/cavum Vergae was related to a one-way valve mechanism between the posterior part of the cavum Vergae and the third ventricle.     

Gene therapy-mediated CD40L and CD28 co-stimulatory signaling blockade plus transient anti-xenograft antibody suppression induces long-term acceptance of cardiac xenografts

BACKGROUND: The authors have previously demonstrated that inhibition of CD28 and CD40 ligand (CD40L) co-stimulatory signals by adenovirus-mediated cytotoxic T-lymphocyte-associated (CTL) antigen 4 (A4) immunoglobulin (Ig) and CD40Ig gene therapies induces tolerance or long-term acceptance in rat liver and heart allograft transplantation. In this study, the authors examined whether co-stimulation blockade with a brief course treatment of FK779, a novel leflunomide derivative, would be an ideal strategy for controlling xenograft rejection. METHODS: Hamster hearts were transplanted into Lewis rats. Adenovirus vector coding (Ad) CD40Ig, CTLA4Ig, or LacZ gene (1 x 10(9) plaque-forming units) was administered intravenously to recipient rats 2 days before or immediately after xenografting. FK779 (10 mg/kg/day) was administered orally to recipients for 7 days beginning on day -1. Graft survival, graft histology, and xenoreactive antibodies were examined. RESULTS.: Both untreated and AdLacZ-treated control rats rejected cardiac xenografts, with a median survival time (MST) of 3 days. Co-stimulatory blockade alone by AdCTLA4Ig, AdCD40Ig, or both could not overcome such delayed xenograft rejection (DXR) (MST, 3-4 days). Under a short-course FK779 treatment that suppressed T-cell-independent xenoreactive antibodies, administration of AdCD40Ig (MST, 30.5 days) but not AdCTLA4Ig (MST, 9 days) significantly prolonged xenograft survival as compared with the FK779 monotherapy (MST, 7 days). In contrast, DXR and cellular rejection were controlled successfully and all xenografts were accepted for over 100 days when AdCTLA4Ig and AdCD40Ig were administered under FK779 induction therapy. However, chronic rejection was present in all long-term surviving xenografts. CONCLUSIONS.: Gene therapy-based co-stimulation blockade with FK779 induction treatment seems to be an attractive strategy with which to control xenograft rejection.     

Transcatheter arterial embolization for bleeding of prostatic artery after prostate biopsy

We present a case of bleeding from the prostatic artery, complicating transrectal ultrasound (TRUS) guided prostate needle biopsy, that responded to transcatheter arterial embolization (TAE). A 62-year-old man with a serum PSA of 4.1 ng/ml was admitted to this institution for a prostate biopsy. He developed hypotension and marked abdominal distension 3 hours after undergoing TRUS guided prostate needle biopsy. CT scanning revealed a massive hematoma extending from the pelvis into the retroperitoneal space. Intra-arterial digital subtraction angiography (IA-DSA) showed extravasation of dye from the right prostatic artery, indicating that it had been damaged during the biopsy procedure. The bleeding was successfully stopped with TAE, using 6 micro coils. TRUS guided prostate biopsy is generally considered a safe procedure, with few complications, and cases of massive hemorrhage into the retroperitoneal space are extremely rare. In cases of arterial retroperitoneal bleeding such as this one, treatment with TAE is fast and accurate.