Extended trans-septal approach for mitral valve surgery: Our early experience

Background Extended trans septal (ETS) approach for mitral valve surgery often divides the artery to the Sino-Atrial node. The clinical implication of this is contentious. We analyzed our early results with ETS approach. Methods Between June 1998 and September 2003 eleven patients underwent mitral valve surgery by ETS approach. Six were females. Age ranged from 19 years to 67 years (median 40 years). Six underwent mitral valve replacement (MVR). Four underwent aortic and mitral (double) valve replacement (DVR). One had mitral valve repair. Three had additional procedures (tricuspid valve repair=1, Coronary artery bypass=1, Aorto bifemoral graft=1). Cardiopulmonary bypass ranged from 64 minutes to 77 minutes (median 72 minutes) for MVR and 112 minutes to 178 minutes (median 140 minutes) for DVR. Aortic cross clamp times ranged from 39 minutes to 52 minutes (median 47 minutes) for MVR and 74 minutes to 120 minutes (median 95 minutes) for DVR. Results There was no mortality or morbidity attributed to the ETS approach. One early death in emergency DVR was due to heart failure. Three patients needed seqeuntial pacing in the immediate post-operative period. Nine out of ten survivors were back to their preoperative rhythms on hospital discharge (6 sinus rhythm; 3 atrial fibrillation). One patient with preoperative trifascicular block who underwent reoperation to fix a paravalvular mitral leak needed a permanent pacemaker (VVI). The follow-up ranged from 1 month to 64 months (median 6 months) and is 100% complete. There was no late death or new arrhythmia. Conclusions Extended trans septal approach is safe. It gives excellent exposure of the mitral valve. division of the sinus node artery is not deleterious in the short to intermediate term. Presented at the 50th Annual Meeting of IACTS. New Delhi, Feb. 2004.     

Relationship of femoral neck areal bone mineral density to volumetric bone mineral density, bone size, and femoral strength in men and women

Summary

Using combined dual-energy X-ray absorptiometry (DXA) and quantitative computed tomography, we demonstrate that men matched with women for femoral neck (FN) areal bone mineral density (aBMD) have lower volumetric BMD (vBMD), higher bone cross-sectional area, and relatively similar values for finite element (FE)-derived bone strength.

Introduction

aBMD by DXA is widely used to identify patients at risk for osteoporotic fractures. aBMD is influenced by bone size (i.e., matched for vBMD, larger bones have higher aBMD), and increasing evidence indicates that absolute aBMD predicts a similar risk of fracture in men and women. Thus, we sought to define the relationships between FN aBMD (assessed by DXA) and vBMD, bone size, and FE-derived femoral strength obtained from quantitative computed tomography scans in men versus women.

Methods

We studied men and women aged 40 to 90?years and not on osteoporosis medications.

Results

In 114 men and 114 women matched for FN aBMD, FN total cross-sectional area was 38% higher (P?P?Conclusions In this cohort of young and old men and women from Rochester, MN, USA who are matched by FN aBMD, because of the offsetting effects of bone size and vBMD, femoral strength and the load-to-strength ratio tended to be relatively similar across the sexes.     

Calcified atherosclerotic plaque - where exactly is the calcium and what does it contain?

Objective  

To understand the morphology and mineral content in calcified atherosclerotic plaques.     

Serum xylosyltransferase 1 level increases during early posttraumatic osteoarthritis in mice with high bone forming potential

Increased proteoglycan (PG) synthesis is essential for the stimulation of cartilage repair processes that take place during the reversible phase of osteoarthritis (OA). In articular cartilage, xylosyltransferase 1 (Xylt1) is the key enzyme that initiates glycosaminoglycan (GAG) chain synthesis by transferring the first sugar residue to the PG core protein. Biological activity of PGs is closely linked to GAG biosynthesis since their polyanionic nature directly contributes to the proper hydration and elastic properties of the cartilage tissue present at the articular interface. The aim of this study was to investigate whether variations in the level of Xylt1 present in serum can be used to predict OA disease progression. The influence of bone forming activity on the systemic release of this enzyme was addressed by experimentally-inducing OA in mice of two different genetic backgrounds that were previously characterized for their distinct bone metabolism: C57BL/6J (B6, high bone remodelers) or C3H/HeJ (C3H, high bone formers). Serum was collected after medial meniscectomy or sham surgeries in young adult mice of these two strains over a period of 3.5months at which point knee histopathology was assessed. A significant increase in serum Xylt1 levels observed shortly after meniscectomy positively correlated with severe cartilage damage evaluated by histological assessment at later time points in mice of the C3H background. In contrast, no temporal regulation of Xylt1 level was found between meniscectomies and control surgeries in B6 mice, which developed OA at a slower rate. Additionally, longitudinal evaluation of the serum levels of other markers of cartilage/bone metabolism (C1,2C, osteocalcin) did not reveal any association with late knee damages. Our results strongly support the idea that serum Xylt1 has a clinical value for monitoring risk of OA progression in young adults with high bone forming potential. Ultimately, the understanding of posttraumatic mechanisms regulating PG synthesis and their modification by GAG will be essential so that interventions that stimulate cartilage regrowth can be undertaken prior to irreversible destruction of the joint tissue. This article is part of a Special Issue entitled "Osteoarthritis".     

Renal cell carcinoma with metastases to the gallbladder: four cases from the National Cancer Institute (NCI) and review of the literature

ObjectiveWe evaluate presentation and outcome of patients with metastatic RCC to the gallbladder from our institution and published literature.MethodsPatients with a history of gallbladder metastasis from RCC were selected from our institution's prospective database. A systematic PubMed search was performed to identify articles describing patients with metastatic RCC to the gallbladder. The final cohort included 33 patients: 4 from our institution and 29 from 28 previously published cases. Survival analysis was conducted using log-rank Kaplan-Meier analysis.ResultsMedian patient age was 63 years and the majority of patients were male. Most patients were asymptomatic and diagnosed with gallbladder metastasis on imaging performed for surveillance or staging. The median time to gallbladder metastasis following nephrectomy was 4 years. Metastasis to the gallbladder occurred both synchronously (33%) and metachronously (67%). Of the patients with available histology, all had clear cell RCC (n = 28). Of all patients, 13 (39%) had metastasis only to the gallbladder, while 20 (61%) had additional sites of metastasis. The most common sites of additional metastasis were contralateral kidney (30%), pancreas (21%), lung (18%), adrenal (18%), and lymph nodes (9%). All patients underwent cholecystectomy. At a median follow up time of 1.5 years after cholecystectomy, 54% of patients had no evidence of disease, 14% were alive with metastasis, 23% had died from metastatic RCC, and 9% died from causes unrelated to their cancer.ConclusionGallbladder metastasis from RCC is a rare event that may occur synchronously or metachronously with most patients being asymptomatic. Clear cell carcinoma appears to be the primary pathology associated with gallbladder metastasis. High rates of bilateral RCC and pancreatic metastasis suggest novel associations in patients with RCC and gallbladder metastasis.     

Immunosuppression withdrawal after auxiliary liver transplantation for acute liver failure

BACKGROUND: The potential for immunosuppression withdrawal is the rationale for auxiliary liver transplantation (AUX) in patients with acute liver failure (ALF). PATIENTS AND METHODS: Forty-four AUX were performed in 28 adults and 16 children with ALF secondary to seronegative hepatitis (n = 20; 45%), paracetamol hepatotoxicity (n = 14; 32%), acute viral hepatitis (hepatitis B virus [HBV] n = 3, Epstein-Barr virus n = 1; 9%), drug-induced hepatitis (n = 3; 7%), autoimmune hepatitis (n = 2; 5%), and mushroom poisoning (n = 1; 2%). All patients fulfilled the King's College Hospital transplant criteria for ALF. After partial hepatectomy, 38 patients received a segmental auxiliary graft and six, a whole auxiliary graft. Immunosuppression was based on calcineurin inhibitors and steroids. RESULTS: Thirty-four patients (77%) are alive after a median follow-up of 30 months (range 4 to 124). Eight adults and two children died of sepsis (n = 6; 14%) at a median interval of 30 days (range 2 to 66), intraoperative cardiac failure (n = 1), brain edema on postoperative day 8 (n = 1), sudden death on day 35 (n = 1), and multiple organ failure associated with HBV recurrence 4 years after transplantation (n = 1). Three patients underwent retransplantation for small-for-size graft syndrome with sepsis on postoperative day 15 (n = 1) and for ductopenic rejection 4 and 15 months after AUX (n = 2). In 10/31 (32%) survivors (6/18 adults and 4/13 children) immunosuppression was completely withdrawn after a median of 19 months. CONCLUSION: Complete immunosuppression withdrawal can be achieved in a significant proportion of patients after AUX for ALF.     

Inhibition of tyrosine-kinase-mediated cellular signaling by tyrphostins AG 126 and AG556 modulates murine experimental acute pancreatitis

BACKGROUND: The effects of the tyrosine kinase inhibitors, tyrphostin AG126 and AG556 in a murine model of acute pancreatitis are investigated. METHODS: Intraperitoneal injection of cerulein in mice resulted in a severe, acute pancreatitis, which was characterized by edema, neutrophil infiltration, tissue hemorrhage, and cell necrosis as well as elevation in the serum activities of amylase or lipase. RESULTS: Infiltration of the pancreatic tissue of these animals with neutrophils (measured as increase in myeloperoxidase activity) was associated with signs of enhanced lipid peroxidation (increased tissue levels of malondialdehyde). Immunohistochemical examination showed a marked increase in immunoreactivity for nitrotyrosine and poly (ADP-ribose) polymerase (PARP) in the pancreas of cerulein-treated mice. Pretreatment or posttreatment with tyrphostin AG126 and AG556, 2 different tyrosine kinase inhibitors, significantly reduced the degree of pancreatic inflammation and tissue injury (histologic score). In particular, the treatment with the 2 tyrosine kinase inhibitors reduced the cerulein-induced nitrotyrosine formation and PARP activation in the pancreas as well as the systemic release of tumor necrosis factor alpha. CONCLUSIONS: This study provides the first evidence that (1) prevention of the activation of protein tyrosine kinases reduces the development of acute pancreatitis, and (2) inhibition of the activity of certain tyrosine kinases may represent a novel approach for the therapy of acute pancreatitis.     

Structural and functional analysis of the semitendinosus tendon after harvest for soft tissue reconstructive procedures: a dynamic ultrasonographic study

Purpose

To assess the potential for regeneration of the hamstring tendons after harvesting for various soft tissue reconstructive procedures, this study uses dynamic, high-resolution ultrasound to evaluate the presence of any tissue in the harvest gap and to characterize tissue functionality.

Methods

Patients who underwent ACL reconstruction using ipsilateral hamstring autograft were identified in the database of a single surgeon. Dynamic 12-MHz sonographic imaging was used to evaluate the ipsilateral and contralateral (control) semitendinosus tendons from their insertion sites to proximal muscle bellies. The presence or absence and echogenicity of tissue in the harvest defect, tissue appearance, degree of retraction of the proximal tendon stump, thickness of gap tissue, and motion of the proximal tendon stump were recorded. Data were analysed with Wilcoxon–Mann–Whitney, sign or binomial tests, with significance of P < 0.05.

Results

Eighteen knees in 15 patients (aged 17–51 years) were studied. The proximal amputated stump was retracted an average of 9.0 ± 7.6 cm (range, 0–18 cm; P = 0.0063). With dynamic testing, 9 of 15 knees demonstrated decreased excursion of the proximal tendon stump when compared to the native, contralateral muscle–tendon unit (P = 0.0039). Tissue was detected in the harvest gap in nine knees, five of which had harvest gap tissue with a disorganized appearance compared to the native tendon (P < 0.0001). Six of these nine knees had tissue in the gap demonstrating either less or no excursion with active knee flexion when compared to the native, contralateral side (P = 0.0313).

Conclusions

The presence of tissue in the harvest gap after ACL reconstruction is variable. When tissue is present, there is proximal retraction of the musculotendinous junction and disorganized appearance of the tissue that does not demonstrate normal excursion or physiological function similar to the native muscle-tendon unit.

Level of evidence

Case series, Level IV.     

Role of F-18 FDG PET/CT in assessing bone marrow involvement in pediatric Hodgkin’s lymphoma

Objectives

The aim of the current study was to assess the utility of F-18-fluoro-2-deoxy-d-glucose (F-18 FDG) positron emission tomography/computed tomography (PET/CT) in assessing bone marrow involvement (BMI) compared to bone marrow biopsy (BMB) in initial staging of Hodgkin’s lymphoma (HL) in pediatric patients.

Methods

Data of 38 pediatric patients (mean age 9.8 years, range 3–18 years) with HL were analyzed for the involvement of bone marrow. All patients underwent non-contrast F-18 FDG PET/CT study. BMB was done in 31 patients from the bilateral iliac crests. Scans were interpreted by two nuclear medicine physicians blinded to the details of BMB.

Results

Of the 31 patients who underwent BMB, 5 patients had lymphomatous involvement on BMB. PET/CT was positive in four of these five patients. In 26 patients negative on BMB, PET was negative in 23 patients and positive in 3 patients for BMI. The sensitivity and negative predictive value of F-18 FDG PET/CT was 87.5 and 96 %, respectively, for BMI.

Conclusions

F-18 FDG PET/CT can predict BMB results with high accuracy. F-18 FDG PET/CT may be used at initial staging of pediatric Hodgkin’s lymphoma as it uncovers unsuspected BMI and BMB may be omitted in patients with PET-positive BMI.