Clinical findings, surgical techniques, prognostic factors for short-term survival and long-term outcome in horses with acquired inguinal hernias: Ninety-eight cases (2005-2020).

OBJECTIVE: To report findings, outcome and determine variables associated with survival in horses with acquired inguinal hernia (AIH). STUDY DESIGN: Retrospective study. ANIMALS: A total of 98 cases in 97 horses. METHODS: The medical records (2005-2020) of horses diagnosed with AIH were reviewed. Retrieved data included signalment, history, clinical variables, surgical aspects, postoperative complications, and short- and long-term outcomes. Logistic regression analyses were used to determine factors associated with short-term survival (p < .05). RESULTS: Manual reduction was attempted in a third of the cases (32/98, 33%) and emergency surgery to reduce the hernia was performed in 64 of 98 (65%) cases. Concurrent small intestinal (SI) volvulus was identified in 26 (26/98, 27%) cases. Castration was the most common technique used to prevent recurrence (64/94, 68%). Overall AIH recurrence rate was 11% (11/98). A total of 59 (59/98, 60%) cases survived to hospital discharge and 49 of 52 (94%) cases were still alive after 12 months. Cases admitted within 10 h of colic signs had increased odds of survival (72%) compared to those admitted after 10 h (26%; p < .001). Draft breeds (p = .021), high heart rate on admission (p = .001) and concurrent SI volvulus (p = .048) were associated with reduced survival to hospital discharge. CONCLUSIONS: Horses with AIH had a higher risk of concurrent SI volvulus and lower survival than reported. Draft breeds, high heart rate on admission and concurrent SI volvulus were associated with reduced short-term survival. CLINICAL SIGNIFICANCE: The results of this study should help in prognostication for horses with AIH.

Mesenchymal stem cell transplantation into the spinal cord of healthy adult horses undergoing cervical ventral interbody fusion.

OBJECTIVE: To determine the feasibility of umbilical cord-derived mesenchymal stem cell (UC-MSC) transplantation into the cervical spinal cord of horses by using fluoroscopy with or without endoscopic guidance and to evaluate the neurological signs and tissue reaction after injection. STUDY DESIGN: Experimental study. ANIMALS: Eight healthy adult horses with no clinical signs of neurological disease. METHODS: After cervical ventral interbody fusion (CVIF), ten million fluorescently labeled allogeneic UC-MSC were injected into the spinal cord under endoscopic and fluoroscopic guidance (n = 5) or fluoroscopic guidance only (n = 3). Postoperative neurological examinations were performed, and horses were humanely killed 48 hours (n = 4) or 14 days (n = 4) postoperatively. Spinal tissues were examined after gross dissection and with bright field and fluorescent microscopy. RESULTS: Needle endoscopy of the cervical canal by ventral approach was associated with intraoperative spinal cord puncture (2/5) and postoperative ataxia (3/5). No intraoperative complications occurred, and one (1/3) horse developed ataxia with cell transplantation under fluoroscopy alone. Umbilical cord-derived MSC were associated with small vessels and detected up to 14 days in the spinal cord. Demyelination was observed in six of eight cases. CONCLUSION: Fluoroscopically guided intramedullary UC-MSC transplantation during CVIF avoids spinal cord trauma and decreases risk of ataxia from endoscopy. Umbilical cord-derived MSC persist in the spinal cord for up to 14 days. Cell injection promotes angiogenesis and induces demyelination of the spinal tissue. CLINICAL SIGNIFICANCE: Umbilical cord-derived MSC transplantation into the spinal cord during CVIF without endoscopy is recommended for future evaluation of cell therapy in horses affected by cervical vertebral compressive myelopathy.

Experimental induction of mycotic plaques in the guttural pouches of horses.

Guttural pouch mycosis (GPM) is a rare but potentially life-threatening condition in horses. GPM is caused by a fungal invasion into the mucosal lining of the guttural pouches and, frequently, the associated neurovascular structures. Although several species of fungi have been associated with this disease, Aspergillus spp. appear to be the most common isolated from the guttural pouches. However, it remains unclear which are the predisposing factors leading to the development of the infection. The objectives of the present study were to experimentally reproduce an infection by Aspergillus fumigatus and to follow the natural evolution of the mycosis. Eight guttural pouches from four horses were experimentally infected by endoscopy-guided intrapouch inoculation of A. fumigatus culture. Horses were monitored for clinical signs and development of fungal plaques through endoscopic examination. Mycotic lesions were observed in all the horses and a spontaneous regression was observed within 15-28 days. No development of clinical signs was noticed. In conclusion, we were able to induce the development of mycotic lesions and to observe a natural regression of these lesions without clinical signs.

LOW-FIELD MAGNETIC RESONANCE IMAGING APPEARANCE OF POSTARTHROSCOPIC MAGNETIC SUSCEPTIBILITY ARTIFACTS IN HORSES.

An awareness of magnetic susceptibility artifacts is important for interpreting prepurchase and postoperative magnetic resonance imaging (MRI) studies in horses. These artifacts occur when a metallic or a paramagnetic substance creates a local magnetic field deformity. Aims of the current experimental study were to determine prevalence of these artifacts after arthroscopy in a sample of nonlame horses, and to describe effects of time and type of pulse sequence on low-field MRI signal intensity and detection of the artifacts. Ten, nonlame Standardbred horses were prospectively recruited. All horses underwent arthroscopy of both metacarpophalangeal joints for purposes unrelated to the study. Serial low-Field MRI examinations were performed on each horse and each joint (before, and 6 and 12 weeks postsurgery). In two horses, more detailed longitudinal evaluations were performed with additional MRI examinations. Magnetic susceptibility artifacts were detected postoperatively at the surgical access sites in eight metacarpophalangeal joints at both 6 and 12 weeks after surgery (40% prevalence). Neither of the two longitudinally followed horses had artifacts at any time. Artifacts were only detected on gradient echo (GRE) sequences. Findings indicated that magnetic susceptibility artifacts can be present in postarthroscopy MRI studies in horses and can persist up to 12 weeks after arthroscopy. For this sample of horses, the artifacts did not interfere with evaluation of the joint. Further longitudinal studies are needed to determine the full duration of magnetic susceptibility artifact persistence in affected tissues.

Percutaneous ultrasound-guided arterial angiography for transarterial coil placement in anesthetized and standing horses.

OBJECTIVE: To (1) describe ultrasound-guided percutaneous introduction of a transarterial angiographic catheter into the common carotid artery (CCA); (2) investigate the feasibility of using angiography of the carotid arteries in the guttural pouch region and assess transarterial coil (TAC) placement into the internal carotid artery (ICA). STUDY DESIGN: Experimental study. ANIMALS: Healthy Standardbred horses (n = 6), aged 5-8 years. METHODS: Six horses had ultrasound-guided percutaneous CCA catheterization and angiography under general anesthesia. Catheterization sites were ultrasonographically evaluated postoperatively. Ten weeks later using the same horses sedated and standing, the same procedure was combined with placement of a TAC in the ICA. RESULTS: Agitated contrast ultrasonography confirmed successful catheterization of the CCA. Needle puncture and introducer-set penetration of the CCA were the main technical difficulties. Radiography and fluoroscopy confirmed successful angiography and TAC placement. Mild hematoma formation was recorded in 4 of 12 procedures. CONCLUSION: Angiography and TCA placement in the ICA can be safely performed using a percutaneous approach to the CCA under ultrasound guidance, in standing or anesthetized horses. This approach might be used for TAC embolization procedure; however, technical difficulties and hematoma formation can impair the procedure.

Omics technologies provide new insights into the molecular physiopathology of equine osteochondrosis.

BACKGROUND: Osteochondrosis (OC(D)) is a juvenile osteo-articular disorder affecting several mammalian species. In horses, OC(D) is considered as a multifactorial disease and has been described as a focal disruption of endochondral ossification leading to the development of osteoarticular lesions. Nevertheless, OC(D) physiopathology is poorly understood. Affected horses may present joint swelling, stiffness and lameness. Thus, OC(D) is a major concern for the equine industry. Our study was designed as an integrative approach using omics technologies for the identification of constitutive defects in epiphyseal cartilage and/or subchondral bone associated with the development of primary lesions to further understand OC(D) pathology. This study compared samples from non-affected joints (hence lesion-free) from OC(D)-affected foals (n = 5, considered predisposed samples) with samples from OC-free foals (n = 5) considered as control samples. Consequently, results are not confounded by changes associated with the evolution of the lesion, but focus on altered constitutive molecular mechanisms. Comparative proteomics and micro computed tomography analyses were performed on predisposed and OC-free bone and cartilage samples. Metabolomics was also performed on synovial fluid from OC-free, OC(D)-affected and predisposed joints. RESULTS: Two lesion subtypes were identified: OCD (lesion with fragment) and OC (osteochondral defects). Modulated proteins were identified using omics technologies (2-DE proteomics) in cartilage and bone from affected foals compare to OC-free foals. These were associated with cellular processes including cell cycle, energy production, cell signaling and adhesion as well as tissue-specific processes such as chondrocyte maturation, extracellular matrix and mineral metabolism. Of these, five had already been identified in synovial fluid of OC-affected foals: ACTG1 (actin, gamma 1), albumin, haptoglobin, FBG (fibrinogen beta chain) and C4BPA (complement component 4 binding protein, alpha). CONCLUSION: This study suggests that OCD lesions may result from a cartilage defect whereas OC lesions may be triggered by both bone and cartilage defects, suggesting that different molecular mechanisms responsible for the equine osteochondrosis lesion subtypes and predisposition could be due to a defect in both bone and cartilage. This study will contribute to refining the definition of OC(D) lesions and may improve diagnosis and development of therapies for horses and other species, including humans.

Cecal vascular hamartoma causing recurrent colic in an Arabian mare.

A 5-year-old mare was treated for recurrent colic and weight loss by surgical removal of an intraluminal cecal mass. Microscopic examination revealed vascular hamartoma. A 6-month follow-up showed an improvement in the general condition of the mare. Vascular hamartoma should be one of the differential diagnoses for weight loss and colic.

Coliques récurrentes causées par un hamartome vasculaire caecal chez une jument Arabe. Une jument de 5 ans a été traitée pour coliques récurrentes et perte de poids par exérèse chirurgicale d'une masse caecale intraluminale. L'examen microscopique a révélé un hamartome vasculaire. Un suivi de 6 mois a montré une amélioration de l'état général de la jument. L'hamartome vasculaire doit faire partie du diagnostic différentiel de l'amaigrissement et des coliques.(Traduit par les auteurs).

Guttural Pouch Mycosis: A Three-Step Therapeutic Approach.

The temporary ligation of the common carotid artery is performed as an emergency aid in cases of guttural pouch mycosis. Its usefulness is put into perspective after an anatomical summary of arterial vascularization involving a guttural pouch. It helps to better understand the need for the cranial (cerebral) and caudal (cardiac) occlusion of an arterial rupture by embolization in order to achieve maximum success in preventing and treating an hemorrhage. Topical oxygen therapy used alone or in a multimodal approach with embolization surgery is performed to promote healing of the inflammatory and mycotic lesions observed when an individual is affected. In conclusion, this three-step therapeutic approach should enable the equine practitioner to better orient their decision tree when faced with this condition which, while rare, can be potentially fatal if poorly treated.

Structure-based design of novel HCV NS5B thumb pocket 2 allosteric inhibitors with submicromolar gt1 replicon potency: discovery of a quinazolinone chemotype.

We describe the structure-based design of a novel lead chemotype that binds to thumb pocket 2 of HCV NS5B polymerase and inhibits cell-based gt1 subgenomic reporter replicons at sub-micromolar concentrations (EC50<200nM). This new class of potent thumb pocket 2 inhibitors features a 1H-quinazolin-4-one scaffold derived from hybridization of a previously reported, low affinity thiazolone chemotype with our recently described anthranilic acid series. Guided by X-ray structural information, a key NS5B-ligand interaction involving the carboxylate group of anthranilic acid based inhibitors was replaced by a neutral two-point hydrogen bonding interaction between the quinazolinone scaffold and the protein backbone. The in vitro ADME and in vivo rat PK profile of representative analogs are also presented and provide areas for future optimization of this new class of HCV polymerase inhibitors.

Trans-arterial coil embolization of the internal carotid artery in standing horses.

OBJECTIVES: To develop transarterial coil embolization (TACE) for occlusion of the internal carotid artery (ICA), in normal standing horses, and to evaluate it use for prevention of hemorrhage in horses with guttural pouch mycosis (GPM). STUDY DESIGN: Prospective study. ANIMALS: Normal horses (n = 8) and 5 with GPM. METHODS: Horses had TACE of the ICA in standing position under fluoroscopic guidance. Four normal horses were euthanatized 2 weeks after TACE for morphologic assessment and 4 were followed for 6 months. The 5 clinically affected horses were evaluated for long-term (10-12 months) success rate and complications. RESULTS: No complications related to the TACE were noted. Up to 30 mL warmed meglumine ioxithalamate was injected and well tolerated. Standing angiography confirmed complete occlusion of all vessels, and coils were positioned as intended; the procedure did not alter local hemodynamics. At 2 weeks, maturing to mature continuous thrombi was seen at the site of the coils. Two clinically affected horses died at day 3 and 12 after surgery from other problems. In the 3 surviving horses, mycotic lesions completely resolved without additional treatment. CONCLUSIONS: TACE under fluoroscopic guidance in standing horses provided a safe, minimally invasive, and effective method for ICA occlusion and should be recommended for individuals at risk of general anesthesia. Residual neurologic deficits are a common sequela, but they do not reflect a treatment failure.

Ex Vivo Comparison of a UV-Polymerizable Methacrylate Adhesive versus an Inverting Pattern as the Second Layer of a Two-Layer Hand-Sewn Jejunal Anastomosis in Horses: A Pilot Study.

Resection and anastomosis of small intestine during colic can lead to adhesions and recurrent colic. Several methods are available to reduce the rate of adhesions in the postoperative period, such as the use of serosal barriers. Surgical glues form a smooth surface, are fast to apply, and could reduce surgery time when performing anastomosis. A recently developed UV-polymerizable methacrylate adhesive (UV-PMA) is designed to anchor into the biological tissues' top surface offering sealant and a smooth cover over the anastomosis site. This adhesive was used ex vivo on fifteen samples of equine jejunum as the second layer of a two-layer anastomosis (1L-UV-PMA group) and compared to a two-layer anastomosis (simple continuous pattern covered with a Cushing pattern; 2L-CT group), in terms of feasibility, bursting strength pressure (BSP), luminal diameter reduction (LDR), and time of construction. Data were analysed using a paired t-test or a chi2-test (P < 0.05). The results showed no statistical difference in BSP, LDR, or any mode of failure between the two anastomosis types. However, the glue anastomosis formed a tunnel-like anastomosis and shredded under pressure, before apparition of leakage, preventing its usage in clinical cases with this methodology. It was concluded that modification of the technique is warranted before testing in clinical cases. A preprint of a former version of the manuscript is available on researchsquare.com, which was not conducted to print and publication after peer reviewing. Since then, the manuscript has been modified to this current version.

Effect of Allogeneic Oral Mucosa Mesenchymal Stromal Cells on Equine Wound Repair.

OBJECTIVE: To assess the clinical value and safety of the application of allogeneic equine oral mucosa mesenchymal stromal cells (OM-MSCs) to wounds. Animals. 8 healthy adult horses without front limb skin lesions or musculoskeletal disease. Procedures. Stem cells were isolated from the oral mucosa of a donor horse. Horses were subjected to the creation of eight full-thickness cutaneous wounds, two on each distal forelimb (FL) and two on both sides of the thorax (TH). Each wound was subjected to one out of four treatments: no medication (T1), hyaluronic acid- (HA-) gel containing OM-MSC (T2), HA-gel containing OM-MSC secretome (T3), and HA-gel alone (T4). Gross macroscopic evaluation and laser digital photographic documentation were regularly performed to allow wound assessment including wound surface area. Full-thickness skin punch biopsy was performed at each site before wound induction (D0, normal skin) and after complete wound healing (D62, repaired skin). RESULTS: All wounds healed without adverse effect at D62. Distal limb wounds are slower to heal than body wounds. OM-MSC and its secretome have a positive impact on TH wound contraction. OM-MSC has a positive impact on the contraction and epithelialization of FL wounds. No significant difference between wound sites before and after treatment was noted at histological examination. Conclusion and Clinical Relevance. Using horse cells harvested from oral mucosa is a feasible technique to produce OM-MSC or its secretome. The gel produced by the combination of these biologic components with HA shows a positive impact when applied during the early stage of wound healing.

The Effect of Topical Oxygen Therapy in Horses Affected with Mycosis of the Guttural Pouch: An Experimental Pilot Study and a Case Series.

Background: The management of bleeding originating from the guttural pouch (GP) has a high success rate, but the resolution of the macroscopic inflammatory lesions in the case of mycosis (GPM) is highly variable; the resolution of neurological disorders is inconstant and challenging. Objectives: Our aim was to test the feasibility and safety of topical oxygen therapy (TOT) in horses after induction of GPM and in cases with naturally occurring disease. Study design: This study was an in vivo experimental and retrospective two-phase study. Methods: During phase 1, the pilot study, both GPs were inoculated with Aspergillus fumigatus. One GP was randomly assigned to receive one to four TOT 30 min sessions with 100% medical oxygen at 9 L/min. Follow-up endoscopic images were assessed for scoring macroscopic inflammatory lesions of the pharynx and both GPs. In phase 2, the clinical study, TOT was administered for 45 to 60 min at 15 L/min in six horses presenting with GPM. Results: In phase 1, TOT administration was easy to perform in the standing horse with no adverse effects. After more than two administrations, macroscopic inflammatory lesions decreased more quickly in size in the treated GP. In phase 2, horses were treated with TOT only (n = 1) or combined with a transarterial coil embolization (TACE) procedure (n = 5). After TOT and discharge from the hospital, nasal discharge resolved in three horses, and improvement was noted in the fourth one. Between days 2 and 10 after admission, upper respiratory tract endoscopy (URTE) indicated size reduction and alteration in the appearance of all the macroscopic inflammatory lesions. The partial or total recovery of neurological disorders (2/4 laryngeal hemiparesis, 3/5 dysphagia, 1/2 dorsal displacement of the soft palate (DDSP), and 1/1 Horner's syndrome) was recorded. Main limitations: In phase 1, the small number of horses did not allow for statistically significant conclusions; in phase 2, clinical signs at admission varied between horses, which made comparison difficult. Conclusions: In adult horses, TOT alone or in combination with TACE is feasible and safe with a propensity to reverse the course and the progression of inflammatory lesions without additional local or systemic treatment.

Role of 70-kDa ribosomal protein S6 kinase, nitric oxide synthase, glycogen synthase kinase-3 beta, and mitochondrial permeability transition pore in desflurane-induced postconditioning in isolated human right atria.

BACKGROUND: Desflurane during early reperfusion has been shown to postcondition human myocardium. Whether it involves "reperfusion injury salvage kinase" pathway remains incompletely studied. The authors tested the involvement of 70-kDa ribosomal protein S6 kinase, nitric oxide synthase, glycogen synthase kinase (GSK)-3beta, and mitochondrial permeability transition pore in desflurane-induced postconditioning. METHODS: The authors recorded isometric contraction of human right atrial trabeculae suspended in an oxygenated Tyrode's solution (34 degrees C, stimulation frequency 1 Hz). After a 30-min hypoxic period, desflurane 6% was administered during the first 5 min of reoxygenation. Desflurane was administered alone or with pretreatment of rapamycin, a 70-kDa ribosomal protein S6 kinase inhibitor, NG-nitro-L-arginine methyl ester, a nitric oxide synthase inhibitor, and atractyloside, the mitochondrial permeability transition pore opener. GSK-3beta inhibitor VII was administered during the first few minutes of reoxygenation alone or in the presence of desflurane 6%, rapamycin, NG-nitro-L-arginine methyl ester, and atractyloside. Developed force at the end of a 60-min reoxygenation period was compared (mean +/- SD). Phosphorylation of GSK-3beta was measured using blotting. RESULTS: Desflurane 6% (84 +/- 4% of baseline) enhanced the recovery of force after 60 min of reoxygenation when compared with the control group (54 +/- 4%, P < 0.0001). Rapamycin (68 +/- 8% of baseline), NG-nitro-L-arginine methyl ester (57 +/- 8%), atractyloside (52 +/- 7%) abolished desflurane-induced postconditioning (P < 0.001). GSK-3beta inhibitor-induced postconditioning (84 +/- 5%, P < 0.0001 vs. control) was not modified by desflurane (78 +/- 6%), rapamycin (81 +/- 6%), and NG-nitro-L-arginine methyl ester (82 +/- 10%), but it was abolished by atractyloside (49 +/- 6%). Desflurane increased the phosphorylation of GSK-3beta (3.30 +/- 0.57-fold increase in desflurane vs. control; P < 0.0001). CONCLUSIONS: In vitro, desflurane-induced postconditioning protects human myocardium through the activation of 70-kDa ribosomal protein S6 kinase, nitric oxide synthase, inhibition, and phosphorylation of GSK-3beta, and preventing mitochondrial permeability transition pore opening.

A case of facial deformity due to bilateral developmental maxillary cheek teeth displacement in an adult horse.

A 7-year-old mare presented with facial deformities associated with oral discomfort and weight loss was found to have bilateral, palatal, developmental displacements of the maxillary 08s, with secondary diastema. Following repulsion of both displaced teeth, the horse regained weight and resumed training. Bony deformities remained visible 9 mo after discharge.

Extracorporeal life support in severe drug intoxication: a retrospective cohort study of seventeen cases.

INTRODUCTION: Cardiovascular failure is the leading cause of death in severe acute drug intoxication. In this setting, we report the feasibility, complications, and outcome of emergency extracorporeal life support (ECLS) in refractory shock or cardiac arrest following a drug overdose. METHODS: This is a retrospective cohort study of 17 patients admitted over a 10-year period for prolonged cardiac arrest or refractory shock following a drug overdose and not responding to optimal conventional treatment. Patients were evaluated in the medical ICU and cardiovascular surgery department of a university hospital. ECLS implantation used a centrifugal pump connected to a hollow-fiber membrane oxygenator and was performed in the operating room (n = 13), intensive care unit (n = 3), or emergency department (n = 1). ECLS was employed for refractory shock and prolonged cardiac arrest in 10 and 7 cases, respectively. RESULTS: The mean duration of external cardiac massage was 101 +/- 55 minutes. Fifteen patients had ingested cardiotoxic drugs, including 11 cases of drugs with membrane stabilizing activity. Time from hospital admission to initiation of ECLS was 6.4 +/- 7.0 hours. Time to ECLS implant was 58 +/- 11 minutes. The mean ECLS flow rate was 3.45 +/- 0.45 L/min. The average ECLS duration was 4.5 +/- 2.4 days. Early complications included limb ischemia (n = 6), femoral thrombus (n = 1), cava inferior thrombus (n = 1), and severe bleeding at the site of cannulation (n = 2). Fifteen patients were weaned off ECLS support and 13 (76%) were discharged to hospital without sequelae. CONCLUSIONS: Based on our experience, we consider ECLS as a last resort, efficient, and relatively safe therapeutic option in this population. However, the uncontrolled nature of our data requires careful interpretation.

Effects of platelet-rich plasma on the repair of wounds on the distal aspect of the forelimb in horses.

OBJECTIVE: To evaluate the effect of platelet-rich plasma on wounds on the distal aspect of the forelimb in horses. ANIMALS: 6 mixed-breed 10- to 15-year-old mares. PROCEDURES: 3 wounds were created on metacarpal regions in each of 6 horses (n = 36 wounds total). Eighteen wounds were treated with platelet-rich plasma and bandaged, whereas 18 control wounds were similarly bandaged with no prior topical treatment. Decrease in wound surface area and the required number of excisions of exuberant granulation tissue were recorded until complete healing. Tissue specimens were taken from wounds at 1 week for histologic examination and measurement of transforming growth factor-beta1 concentrations and at closure for histologic examination, biomechanical evaluation, and measurement of collagen type I and type III mRNA. RESULTS: Platelet-rich plasma favored excessive development of granulation tissue and significantly slowed wound healing at 1, 2, and 3 weeks after surgery. Transforming growth factor-beta1 had a 1.6-fold higher concentration in treated wounds, compared with untreated wounds. Histologic, biomechanical, and gene expression data did not differ significantly between treated and control wounds. CONCLUSIONS AND CLINICAL RELEVANCE: Topical application of autologous platelet-rich plasma did not accelerate or improve the quality of repair of small granulating wounds on limbs of horses. This treatment may better suit wounds with massive tissue loss or, alternatively, chronic wounds that would benefit from a fresh source of mediators to accelerate the healing process.

Diagnostic performance of 16- and 64-section spiral CT for coronary artery bypass graft assessment: meta-analysis.

PURPOSE: To perform a meta-analysis to evaluate the accuracy of 16- and 64-section spiral computed tomography (CT) to help assess coronary artery bypass grafts (CABGs). MATERIALS AND METHODS: The MEDLINE, Cochrane library, and BioMed Central databases were searched for relevant original articles published up to May 2007. Major criteria for article inclusion were that it (a) used multisection CT as a diagnostic test for the assessment of significant lesions (occlusion or >50% stenosis) of CABG, (b) used a 16- or 64-section scanner, and (c) used coronary angiography as the reference standard. After data extraction, the analysis was performed according to a random-effects model. Between-study statistical heterogeneity was also assessed by using the Cochran Q chi(2) test. RESULTS: Of 158 screened articles, 15 fulfilled all inclusion criteria. Graft assessability (including distal anastomosis) ranged from 78%-100% among all included studies (mean, 92.4%; 90% with 16- and 96% with 64-section CT; P < .001). Statistical heterogeneity was observed for specificity and positive likelihood ratio (LR), justifying the use of the random-effects model. The analysis, pooled from 15 studies (723 patients, 2023 CABGs), provided the following results for the assessment of graft obstruction (occlusion and >50% stenosis): sensitivity, 97.6% (95% confidence interval [CI]: 96%, 98.6%); specificity, 96.7% (95% CI: 95.6%, 97.5%); positive predictive value, 92.7% (95% CI: 90.5%, 94.6%); negative predictive value, 98.9% (95% CI: 98.2%, 99.4%); positive LR, 23.42 (95% CI: 13.69, 40.07); negative LR, 0.045 (95% CI: 0.028, 0.071); and diagnostic odds ratio, 780.32 (95% CI: 379.12, 1606.1). CONCLUSION: Multisection CT provided high accuracy for the evaluation of CABG obstruction in assessable conduits, and might be used as a noninvasive tool for the evaluation of suspected graft dysfunction in patients who are at high risk for complications from coronary angiography.

Signaling pathways involved in desflurane-induced postconditioning in human atrial myocardium in vitro.

BACKGROUND: Isoflurane and sevoflurane have been shown to elicit myocardial postconditioning, but the effect of desflurane remain unknown. The authors studied the mechanisms involved in desflurane-induced myocardial postconditioning. METHODS: Contracting isolated human right atrial trabeculae (34 degrees C, stimulation frequency 1 Hz) were exposed to 30-min hypoxia followed by 60-min reoxygenation. Desflurane at 3%, 6%, and 9% was administered during the first 5-min of reoxygenation. Postconditioning with 6% desflurane was studied in the presence of 1 microM calphostin C, a protein kinase C inhibitor; 800 mm 5-hydroxydecanoate, a mitochondrial adenosine triphosphate-sensitive potassium channels antagonist; 1 microM Akt inhibitor; 20 microM PD89058, an extracellular-regulated kinase 1/2 inhibitor; and 1 microM SB 202190, a p38 mitogen-activated protein kinase inhibitor. The force of contraction at the end of the 60-min reoxygenation period was compared (mean +/- SD). The p38 mitogen-activated protein kinase phosphorylation was studied using Western blotting. RESULTS: Desflurane at 3% (77 +/- 10% of baseline), 6% (90 +/- 14% of baseline), and 9% (86 +/- 11% of baseline) enhanced the recovery of force after 60 min of reoxygenation as compared with the control group (51 +/- 9% of baseline; P < 0.001). Calphostin C (55 +/- 3% of baseline), 5-hydroxydecanoate (53 +/- 3% of baseline), Akt inhibitor (57 +/- 8% of baseline), PD89058 (64 +/- 6% of baseline), and SB 202190 (61 +/- 3% of baseline) abolished desflurane-induced postconditioning. Western blot analysis showed that 6% desflurane increased p38 mitogen-activated protein kinase phosphorylation. CONCLUSIONS: In vitro, desflurane postconditioned human atrial myocardium through protein kinase C activation, opening of mitochondrial adenosine triphosphate-sensitive potassium channels, Akt and extracellular-regulated kinase 1/2 activation, and p38 mitogen-activated protein kinase phosphorylation.

Etomidate has no effect on hypoxia reoxygenation and hypoxic preconditioning in isolated human right atrial myocardium.

BACKGROUND: We examined the effects of etomidate on recovery of contractile function after hypoxia reoxygenation and hypoxic preconditioning in vitro using isolated human myocardium. METHODS: Human right atrial myocardium were obtained at the time of cardiac surgery from 38 adults patients. We recorded isometric force of contraction (FoC) of atrial trabeculae suspended in an oxygenated Tyrode's solution (34 degrees C, stimulation frequency 1 Hz). In all groups, a 30-min hypoxic period was followed by 60 min of reoxygenation (HR). In separate groups, muscles were exposed to etomidate (10(-7), 10(-6), 10(-5) M) 10 min before and throughout the HR periods. Hypoxic preconditioning was induced by 4-min hypoxia followed by 7-min reoxygenation applied before HR periods. Etomidate 10(-5) M was administered before, throughout, and after the hypoxic preconditioning stimulus. Recovery of FoC (expressed as % of baseline value) at the end of HR was compared among groups. RESULTS: Compared with the control group (FoC: 52%+/-10%), etomidate 10(-7) M (FoC: 57%+/-9%; P=0.24), 10(-6) M (FoC: 61%+/-11%; P=0.10), and 10(-5) M (FoC: 54%+/-9%; P=0.29) did not modify the recovery of FoC after HR. Hypoxic preconditioning-induced increase in the recovery of FoC (87%+/-5%; P<0.001 vs control group) was not modified in the presence of etomidate 10(-5) M (FoC: 86%+/-7%; P=0.74 vs hypoxic preconditioning group). CONCLUSIONS: Etomidate did not modify the in vitro FoC of human myocardium exposed to HR. Furthermore, etomidate did not modify the protective effect of hypoxic preconditioning.