Surgical Occlusion Research Articles

The Barrow Ruptured Aneurysm Trial: 6-year results.

The authors report the 6-year results of the Barrow Ruptured Aneurysm Trial (BRAT). This ongoing randomized trial, with the final goal of a 10-year follow-up, compares the safety and efficacy of surgical clip occlusion and endovascular coil embolization in patients presenting with subarachnoid hemorrhage (SAH) from a ruptured aneurysm. The 1- and 3-year results of this trial have been previously reported. In total, 500 patients with an SAH met the entry criteria and were enrolled in the study. Of these patients, 471 were randomly assigned to the treatments: 238 to surgical clipping and 233 to endovascular coiling. Six patients who died before treatment and 57 patients with nonaneurysmal SAHs were excluded, leaving a total of 408 patients who underwent clipping (209 assigned) or coiling (199 assigned). Whether to treat patients within the assigned group or to cross over patients to the other group was at the discretion of the treating physician; 38% (75/199) of the patients assigned to coiling were crossed over to clipping and 1.9% (4/209) assigned to clipping were crossed over to coiling. The outcome data were collected by a dedicated nurse practitioner. The primary outcome analysis was based on the assigned treatment group; poor outcome was defined as a modified Rankin Scale (mRS) score > 2 and was independently adjudicated. Six years after randomization, 336 (82%) of 408 patients who had been treated were available for examination. On the basis of an mRS score of > 2, and similar to the results at the 3-year follow-up, no significant difference in outcomes (p = 0.24) was detected between the 2 treatment groups. Complete aneurysm obliteration at 6 years was achieved in 96% (111/116) of the clipping group and in 48% (23/48) of the coiling group (p < 0.0001). In the period between the 3- and 6-year follow-ups, 3 additional patients assigned to coiling and none assigned to clipping received retreatment, for overall retreatment rates of 4.6% (13/280) for clipping and 16.4% (21/128) for coiling (p < 0.0001). When aneurysm location was considered, the 6-year results continued to match the previously reported results, with no difference in outcome for anterior circulation aneurysms at most time points. Of the anterior circulation aneurysms assigned to coiling treatment, 42% (70/168) were crossed over to clipping treatment. The outcomes for posterior circulation aneurysms continued to favor coiling. The randomization process was unexpectedly skewed, with 18 of 21 treated aneurysms of the posterior inferior cerebellar artery (PICA) being assigned to clipping, but even when PICA aneurysms were removed from the analysis, outcomes for the posterior circulation aneurysms still favored coiling. Although BRAT was statistically underpowered to detect small differences, these results suggest little difference in outcome between the 2 treatments for anterior circulation aneurysms. This was not the case for the posterior circulation aneurysms, where coil embolization appeared to provide a sustained advantage over clipping. Aneurysm obliteration rates in BRAT were significantly lower and retreatment rates significantly higher in the patients undergoing coiling than in those undergoing clipping. However, despite the fact that retreatment rates were higher after coiling, no recurrent hemorrhages were known to have occurred in patients undergoing coiling in BRAT who were followed up for 6 years. Sufficient questions remain about the relative benefits of the 2 treatment modalities to warrant further well-designed randomized trials.

Bailout innominate vein—right atrial bypass for innominate vein disruption

Disruption of the innominate vein during cardiac surgery is an uncommon emergency, is life threatening, and may result in an extreme severity of superior vena cava syndrome. The innominate vein at the superior vena cava junction was injured, requiring surgical occlusion. As bailout procedure to avoid superior vena cava syndrome, a venous bypass between the innominate vein and the right atrium was constructed. Subsequent three-graft coronary bypass was performed. This conduit was patent at 48 h and four postoperative weeks. The patient did not develop superior vena cava syndrome.

Inhibitors of the Renin‐Angiotensin System (RAS) Completely Prevents Cardiac Hypertrophy (CH) Induced by Ischemic Renal Injury (IRI) via Angiotensin II (AngII)/Toll‐Like Receptors (TLR) Cross‐Talk

ObjectivesThe cardio‐renal syndrome comprises a set of pathophysiological kidney‐heart interactions. Renal injury promotes release of inflammatory cytokines (CTK), which may act through cardiac TLR and lead to CH, as well as AngII. This study aims to investigate a possible interaction between TLR and RAS in CH model induced by IRI.MethodsC57BL/6 male mice (n=84) treated with Losartan (Los‐10 mg/kg) or Enalapril (Ena‐40 mg/kg) were subjected to surgical occlusion of left renal pedicle and kept under observation for 20d. IRI, CH and systolic blood pressure (SBP) were assessed by morphologic, molecular and functional parameters, as well as tail‐cuff plethysmography and electrocardiography (ECG) before and after surgery. Serum/cardiac RAS components, TLR2/TLR4 and inflammatory CTK were evaluated by Real‐Time PCR, protein expression and ELISA.ResultsThe successfully‐performed IRI induced an enhancement of serum IL‐6, TNF‐a and IFN‐y (p&lt;0.001) and did not promote SBP alteration. CH was observed after 12d of reperfusion, when cardiac AT1, ACE2, TLR2/TLR4 levels were increased (p&lt;0.001). Los/Ena prevented CH (p&lt;0.001) without changing SBP and modulated serum AngII and CTK levels (p&lt;0.05). Also, ECG showed an improvement in cardiac function.ConclusionThe presented data shows that RAS inhibition is able to completely prevent CH via regulation of cardiac TLR and serum AngII/CTK levels, suggesting the existence of a key cross‐talk between TLR and RAS in CH induced by IRI. Financial Support: FAPESP; CNPq.

Cardiac Tissue Sensitization to the Sympathetic Nervous System in Renal Ischemia/Reperfusion induced Cardiac Hypertrophy

ObjectivesHeart and kidney share functions of the conservation of homeostasis. Acute kidney injury occurs by an abrupt decline in renal function and can lead to the development of cardiac hypertrophy (CH), among other ways, by catecholamines release into circulation. This study aims to investigate possible modulation of sympathetic nervous system (SNS) in CH development through the cardiac beta‐adrenergic receptors pathway in CH‐induced ischemic renal injury model.MethodsC57BL/6 male mice (n=88) were subjected to surgical occlusion of left renal pedicle for 60min followed for reperfusion (REP) for 12 and 15 days. Another group of animals were treated with Propranolol (10 mg/kg/day) for 5 days after occlusion. Morphological and molecular parameters were used to evaluate kidney and CH status.ResultsRenal ischemia/reperfusion was able to induce CH after 12d. The left kidney mass was reduced (p&lt;0.05) and an increase on Vimentin and urea levels were observed (p&lt;0.001) and (p&lt;0.05), respectively. Beta‐adrenergic receptors increased after 12days when compared to Sham group (p&lt;0.05). Treatment with SNS inhibitor was able to improve the reduction of the left kidney mass.ConclusionCH was accompanied by an increase in levels of beta‐adrenergic receptor, suggesting an increase in cardiac sensitivity to SNS.

Rescue Bypass for Revascularization After Ischemic Complications in the Treatment of Giant or Complex Intracranial Aneurysms

Surgical trapping or endovascular deconstruction commonly is used for the treatment of giant or complex intracranial aneurysms. Preoperative balloon test occlusion and cerebral blood flow studies and intraoperative neurophysiologic monitoring can indicate whether sufficient collateralization exists or whether revascularization is needed. Hemodynamic insufficiency can occur, however, despite passing these tests, necessitating posttreatment revascularization. We conducted a retrospective review of patients who underwent surgical or endovascular parent vessel occlusion for the management of giant or complex intracranial aneurysms and subsequently required rescue bypass for symptoms of hemodynamic insufficiency. Pre- and postrevascularization functional status was measured with the modified Rankin Scale. During a 15-year period from 1997 to 2012, a rescue bypass was performed in 5 patients each harboring a giant or complex intracranial internal carotid artery (ICA) aneurysm that was treated with surgical trapping or endovascular deconstruction in a previous procedure. All bypasses were extracranial-to-intracranial and included cervical ICA to middle cerebral artery, subclavian to middle cerebral artery, and cervical ICA to supraclinoid ICA anastomoses via either a saphenous vein or radial artery graft. Functional outcome at time of last follow-up was improved in each patient (improvement in modified Rankin Scale of 1-3 points). Ischemic complications must always be anticipated in the treatment of giant or complex intracranial aneurysms, even if pre- and intraoperative blood flow studies indicate sufficient collateralization. Here we show that extracranial-to-intracranial bypass is an effective option to rescue unanticipated hemodynamic insufficiency after parent vessel occlusion. This study emphasizes the need for cerebrovascular surgeons to maintain proficiency in complex bypass techniques.

Transthoracic closure of atrial septal defect and ventricular septal defect without cardiopulmonary bypass.

The minimally invasive surgical transthoracic occlusion of an atrial septal defect (ASD) or a ventricular septal defect (VSD) is an increasingly widespread alternative treatment for congenital heart disease. The aim of this study is to summarize our clinical experience with minimally invasive surgical transthoracic occlusion of ASD and VSD without cardiopulmonary bypass (CPB). Between April 2011 and October 2012, 27 patients with ASD and 95 patients with VSD (78 men and 44 women) were considered for minimally invasive surgical transthoracic occlusion without CPB. A small infrasternal incision (2.0-4.0 cm) was made under general anesthesia, under transesophageal echocardiography (TEE) guidance; the ASD and VSD were closed by using an appropriate occluder; and TEE was performed simultaneously to demonstrate the position of the device, any residual shunting, or encroachment on the atrioventricular valve, coronary sinus, or aortic valve. Successful transthoracic occlusion was performed in all 122 patients without complications. No complications such as third-degree atrioventricular block and residual shunting occurred after the procedures. The ventilation time was 2.2 ± 1.2 h, and the average length of hospital stay was 4.7 ± 1.7 days. All patients received aspirin at 3 mg·kg(-1)·day(-1) (maximum 100 mg/day) 24 h after the procedure. Minimally invasive surgical transthoracic occlusion without CPB is a new treatment that has many advantages such as causing little trauma, promoting quick recovery, having less complications, and avoiding radiation damage. However, the appropriate selection of patients is still key to improving the success rate of the operation.

Dodecafluoropentane emulsion delays and reduces MRI markers of infarction in a rat stroke model: a preliminary report

BackgroundDodecafluoropentane emulsion (DDFPe), an oxygen transport agent, has been shown to reduce infarct volume in animal models of acute ischemic stroke (AIS). Our study assesses the effect of DDFPe on MRI markers of infarct evolution in the early hours after vascular occlusion in a rat AIS model. We hypothesized that DDFPe will delay the development of MRI markers of AIS and/or reduce the extent of infarction. MethodsPermanent, unilateral surgical occlusion of the middle cerebral and common carotid arteries was performed in control (n=4) and treatment (n=10) rats. The treatment group received 1 IV dose of 2% w/v DDFPe at 0.6mL/kg at 1hour post-occlusion versus none. Diffusion-weighted (DWI) and inversion recovery (IR) MRI sequences were obtained over the 4hours following occlusion. Infarct extent was quantified by number of abnormal MRI slices per sequence for each group and time point. Student's T-test was applied. ResultsDDFPe-treated rats demonstrated reduced infarct extent versus controls over combined time points on IR at 5.43±0.40 (mean±standard error) abnormal slices vs. 7.38±0.58 (P=0.01) and on DWI at 5.21±0.54 vs. 9.00±0.95 (P<0.01). Development of abnormal MRI signal was delayed in the treatment group. ConclusionsDDFPe delays and reduces MRI markers of AIS in the early hours following vascular occlusion in a rat stroke model. Further investigation of DDFPe as a neuroprotectant is warranted.

Abstract 654: Endothelial Ephrin-B2 Essential for Arterial Vasodilation is also Required for Acute Ischemic Recovery

Rationale: The cell surface protein ephrin-B2 is expressed in arterial and not venous endothelial cells throughout development and adulthood. We have recently reported that endothelial ephrin-B2 is essential in acute arterial vasodilation. Here we proposed that endothelial ephrin-B2 plays important protective roles against acute ischemia. Objective: We investigated the role of endothelial ephrin-B2 following experimental hindlimb ischemia in mice lacking ephrin-B2 specifically in the endothelium. Methods and Results: We performed femoral artery occlusion in mice lacking the ephrin-B2 gene specifically in endothelial cells. We found that the mutant mice exhibited lower residual blood flow than controls immediately following the surgical occlusion by laser doppler perfusion imaging. The mutant mice also developed gangrene not seen in controls soon after the occlusion. Histologically the tissue regeneration and recovery were impaired in the hindlimb of the mutant mice. S-nitrosoglutathione, a donor for nitric oxide, alleviated the perfusion impairment immediately after the occlusion and improved the tissue survival and recovery in the mutants to levels comparable to those in controls. We further demonstrated that acetylcholine-stimulated nitric oxide production was impaired in ephrin-B2 mutant aortae, detected by both chemiluminescence that measures NOx and electron spin resonance that measures bioavailable NO. Conclusions: Our data demonstrate that mice lacking ephrin-B2 in endothelial cells are defective in acute ischemic recovery after femoral artery occlusion. Our data also suggest that endothelial ephrin-B2 could potentially interact with the nitric oxide pathway that is critical in its function in arterial dilation and protection against ischemia.

Surgical left atrial appendage occlusion during cardiac surgery for patients with atrial fibrillation: a meta-analysis.

Concomitant left atrial appendage occlusion (LAAO) during surgical ablation has emerged as a potential treatment strategy to reduce stroke and perioperative mortality in patients with atrial fibrillation (AF). The present meta-analysis aims to assess current evidence on the efficacy and safety between LAAO and LAA preservation cohorts for patients undergoing cardiac surgery. Electronic searches were performed using six electronic databases from their inception to November 2013, identifying all relevant comparative randomized and observational studies comparing LAAO with non-LAAO in AF patients undergoing cardiac surgery. Data were extracted and analysed according to predefined endpoints including mortality, stroke, postoperative AF and reoperation for bleeding. Seven relevant studies identified for qualitative and quantitative analyses, including 3653 patients undergoing LAAO (n = 1716) versus non-LAAO (n = 1937). Stroke incidence was significantly reduced in the LAAO occlusion group at the 30-day follow-up [0.95 vs 1.9%; odds ratio (OR) 0.46; P = 0.005] and the latest follow-up (1.4 vs 4.1%; OR 0.48; P = 0.01), compared with the non-LAAO group. Incidence of all-cause mortality was significantly decreased with LAAO (1.9 vs 5%; OR 0.38; P = 0.0003), while postoperative AF and reoperation for bleeding was comparable. While acknowledging the limitations and inadequate statistical power of the available evidence, this study suggests LAAO as a promising strategy for stroke reduction perioperatively and at the short-term follow-up without a significant increase in complications. Larger randomized studies in the future are required, with clearer surgical and anticoagulation protocols and adequate long-term follow-up, to validate the clinical efficacy of LAAO versus non-LAAO groups.

Evaluation of the WATCHMAN left atrial appendage closure device

Left atrial appendage device occlusion for the preventions of systemic thromboembolism and stroke represents a major breakthrough in the field of cardiovascular disease. The wide prevalence of atrial fibrillation with devastating consequences of thromboembolic stroke as a result of thrombus arising from the left atrial appendage has led to the development of transcatheter and surgical based occlusion devices. Though this device is yet to be formally approved for a clinical indication in the USA, the WATCHMAN appendage occlusion device remains the most rigorously examined and studied of all transcatheter-based devices in this space. This review will focus on the needs assessment in this space, the technology of the current WATCHMAN device, trials and studies looking at safety and efficacy, specific patient populations who might benefit as well as future perspectives.

Effect of testosterone on the cereble cortex Bcl-2 expression and oxidative stress in a rat model of vascular dementia

Objectives to investigate the effect of testosterone on the cerebral cortex Bcl-2 expression and oxidative stress in a rat model of vascular dementia (VD). Methods Forty-eight Sprague-Dawley adult male rats were divided into four groups (n=12, each) as follows (i) untreated control, (ii) rats exposed to surgical permanent bilateral occlusion of the common carotid arteries (BCCAO) leading to chronic cerebral hypoperfusion, (iii) rats exposed to BCCAO then received testosterone (0.5 mg/ kg S.C., three times/ week, S.C.) (BCCAO + Tes) for 4 weeks and (iv) rats exposed to BCCAO then received donepezil (3 mg/kg/ day; i.p.) (BCCAO + DON) for 4 weeks. Levels of acetylcholine and norepinephrine in the cerebral cortex were measured. Furthermore, the expression of Bcl-2 in the cerebral cortex and malondialdehyde (MDA), non-enzymatic (reduced glutathione, GSH) and enzymatic [superoxide dismutase (SOD) and catalase (CAT)] anti-oxidants were determined. Histopathological studies of the cerebral cortex were performed. Results BCCAO decreased the expression of Bcl-2 as well as the central level of acetylcholine and norepinephrine as compared to control rats. Also, increased the cerebral cortex level of MDA and decreased the enzymatic and non-enzymatic antioxidant. Treatment with testosterone and donepezil increased acetylcholine and norepinephrine significantly when compared with BCCAO rats. Testosterone significantly increased the expression of Bcl-2 and antioxidant system with significant reduction in MDA. Conclusion Testosterone might employ neuroprotective effects through increasing the expression of Bcl-2 as well as ameliorating the oxidative stress induced by BCCAO in rat model of DA.

First experiences with an individual nasal olive in patients with hereditary haemorrhagic telangiectasia (HHT).

Hereditary haemorrhagic teleangiectasia (HHT) is most notably characterized by vulnerable vascular formations of the nasal superficial mucosa. Epistaxis is one of the most common symptoms of the afflicted patients, with an incidence of more than 90 %. A variable series of treatments have been described, ranging from nasal ointments to the complete surgical occlusion of the nose. The objective of this pilot study is the presentation of first experiences in treating patients suffering from HHT and chronically recurrent epistaxis with an individual nasal olive made from silicone. Eleven patients (six men, five women) aging from 44 to 80 years with known HHT were treated at the ENT department of Homburg/Saar between October 2008 and July 2012 because of nasal bleeding by Nd:YAG laser or argon plasma coagulation. After the surgical treatment, an imprint of the nasal aditus was taken to manufacture an individual custom-made silicone nasal olive. Patients were wearing the nasal olive for 3-8 h a day. Check-ups were made every 6 months. Epistaxis severity score (ESS) was used pre- and post-nasal olive application. The observation period was 12-48 months. The utilization of the silicone nasal olive led to a distinct reduction of epistaxis events. Apart from the nasal olive, our patients needed no further treatment of the nose during the observation period except for a nasal ointment. Insertion and removal of the nasal olive were handled by the patients themselves. The local manipulation in handling the nasal olive caused no epistaxis itself. A significant improvement of the ESS and satisfaction was reported in all patients. Use of an individually manufactured silicone nasal olive is a promising extension to the established treatments of epistaxis in HHT patients. Tolerance towards this treatment by the patients was high due to the low personal burden and encumbrance. The extended use of the presented method in HHT patients may be beneficial. However, a more prolonged observation period is necessary in the future to judge the long-term efficiency of individual nasal olives.

Cross‐talk between Toll‐like receptors and renin angiotensin system in a cardiac hypertrophy model induced by renal ischemia/reperfusion (404.5)

Objectives: The cardio‐renal syndrome comprises a set of pathophysiological kidney‐heart interactions. Renal inflammatory conditions are able to promote the release of inflammatory cytokines, which may act through cardiac TLR, promoting cardiovascular diseases such as cardiac hypertrophy (CH), as well as angiotensin II. This study aims to investigate a possible interaction between TLR and RAS in a model of CH induced by ischemic renal injury. Methods: C57BL/6 male mice (n=85) were subjected to surgical occlusion of left renal pedicle. Mice were treated with Los (10 mg/kg/day) or Ena (40 mg/kg/day) and kept under observation for 12, 15 or 20 days of reperfusion (REP). Kidney injury and CH were assessed by morphologic and molecular parameters. Cardiac and serum cytokines and protein and mRNA levels of cardiac RAS components and TLR2 and TLR4 were evaluated. Results: The succesfully‐performed ischemic protocol induced CH after 12d of REP, which was accompanied by enhanced IL‐6 levels in serum. CH were completely reversed by Los and Ena treatment. At the same time point, cardiac AT1, ACE2, TLR2 and TLR4 levels were increased (p&lt;0.001). Treatment with RAS inhibitors abolished this increase to levels similar to control group. Conclusion: RAS may modulate CH through regulation of TLRs levels in the heart, suggesting the existence of a important cross‐talk between TLR and RAS in CH induced by renal ischemia/reperfusion.

The occasional finding of a ventricular septal defect

Certain congenital cardiac defects may go undetected for several years due to lack of symptoms and signs. Ventricular septal defects can occur as an isolate finding or as part of more congenital cardiac malformations [1–9]. The natural history of ventricular septal defects depends on the size of the defect and on the pulmonary resistance. Surgical closure, transcatheter occlusion and spontaneous closure have been reported [10–17]. We present the occasional finding of a ventricular septal defect in a 55-year-old Italian man reporting a recent history of dyspnea. He also reported a history of cancer with a successful lung lobectomy 8 years previously [18–21]. ECG (Fig. 1) has shown amild right bundle branch block [22–24] that was not seen previously. Echocardiographic evaluation revealed a ventricular septal defect a systolic shunt and with a mild right ventricular enlargement (Fig. 2 Panels A, B and C). Also this case focuses attention on the finding of a ventricular septal defect.

Abstract 113: Dodecafluoropentane Emulsion Delays and Reduces MRI Markers of Infarction in a Rat Stroke Model

Introduction: Dodecafluoropentane emulsion (DDFPe), a perfluorocarbon suspension, transports oxygen to ischemic regions of the brain, making it an ideal neuroprotectant for patients with acute stroke. Although DDFPe has been shown through analysis of excised tissue to reduce infarct volume, relatively little is known about the mechanism of DDFPe in vivo. We assess the effect of intravenous (IV) DDFPe on MRI findings in stroke evolution in the early hours after vascular occlusion in a rat stroke model. Hypothesis: We hypothesize that DDFPe will delay the development of MRI markers of acute ischemic stroke and/or reduce infarct volume compared to controls. Methods: With IACUC approval rats were assigned to control (n=4) and treatment (n=10) groups. All rats underwent permanent, unilateral surgical occlusion of the middle cerebral and common carotid arteries. The treatment group received 1 IV dose of 2% w/v DDFPe at 0.6 mL/kg at 1 hour post-occlusion while the control group received none. Diffusion Weighted (DWI) and Inversion Recovery (IR) MRI sequences were obtained over 4 hours after occlusion. Scans were reviewed and scored by consensus of two board certified and blinded radiologists, and the number of abnormal MRI slices per sequence was tallied for each group and time point. Student’s T-test was applied. Results: The mean ±SE numbers of abnormal slices were decreased in the DDFPe group vs. control over total time points for IR at 5.43 ±0.40 vs. 7.38 SE ±0.58 (P=0.01) and DWI at 9.14 ±1.11 vs. 13.88 ±1.79 (P=0.03). Development of abnormal DWI and IR signal was delayed by DDFPe (see Graph) with significance for IR at 2 hours at 5.5 ±0.97 vs. 8.25 ±0.63 (P=0.04) and 3 hours at 5.14 ±0.83 vs. 7.75 ±0.48 (P=0.02). Conclusions: DDFPe delays and reduces MRI markers of acute ischemic stroke in the early hours following vascular occlusion in a rat stroke model. Further study is warranted.

Rationale and design of the Left Atrial Appendage Occlusion Study (LAAOS) III.

Occlusion of the left atrial appendage (LAA) is a promising approach to stroke prevention in atrial fibrillation (AF). However, evidence of its efficacy and safety to date is lacking. We herein describe the rationale and design of a definitive LAA occlusion trial in cardiac surgical patients with AF. We plan to randomize 4,700 patients with AF in whom on-pump cardiac surgical procedure is planned to undergo LAA occlusion or no LAA occlusion. The primary outcome is the first occurrence of stroke or systemic arterial embolism over a mean follow-up of four years. Other outcomes include total mortality, operative safety outcomes (chest tube output in the first post-operative 24 hours, rate of post-operative re-exploration for bleeding in the first 48 hours post-surgery and 30-day mortality), re-hospitalization for heart failure, major bleed, and myocardial infarction. Left Atrial Appendage Occlusion Study (LAAOS) III is funded in a vanguard phase by the Canadian Institutes for Health Research (CIHR), the Canadian Network and Centre for Trials Internationally, and the McMaster University Surgical Associates. As of September 9, 2013, 162 patients have been recruited into the study. LAAOS III will be the largest trial to explore the efficacy of LAA occlusion for stroke prevention. Its results will lead to a better understanding of stroke in AF and the safety and efficacy of surgical LAA occlusion.

Spinal cord involvement in patients with cirrhosis

A severe spinal cord involvement may rarely occur in patients with cirrhosis and other chronic liver diseases; this complication is usually associated with overt liver failure and surgical or spontaneous porto-systemic shunt. Hepatic myelopathy (HM) is characterized by progressive weakness and spasticity of the lower extremities, while sensory and sphincter disturbances have rarely been described and are usually less important. The diagnosis is assigned in the appropriate clinical setting on clinical grounds after the exclusion of other clinical entities leading to spastic paraparesis. Magnetic resonance imaging is often unremarkable; however, also intracerebral corticospinal tract abnormalities have been reported recently. The study of motor evoked potentials may disclose central conduction abnormalities even before HM is clinically manifest. HM responds poorly to blood ammonia-lowering and other conservative medical therapy. Liver transplantation represents a potentially definitive treatment for HM in patients with decompensated cirrhosis of Child-Pugh B and C grades. Other surgical treatment options in HM include surgical ligation, shunt reduction, or occlusion by interventional procedures.

Bail-out transcatheter aortic valve implantation to reduce severe acute aortic regurgitation in a failing homograft secondary to HeartMate II ventricular assistance device

Left ventricular assistance with surgically implanted pump devices like the HeartMate may be crucial in selected patient with end-stage heart failure. However, mainly due to its high aortic output, the pump itself may induce severe aortic regurgitation that could result in paradoxycal worsening of the anterograde perfusion after the initiation of the support. Surgical or percutaneous occlusion of the aortic valve has proved useful in these kinds of patients. Here we present a successful case of bail-out CoreValve implantation after HeartMate II positioning complicated by acute severe aortic regurgitation in a patient with a failing homograft and end-stage ventricular dysfunction, ineligible for heart transplanation.

Reproducibility of small animal cine and scar cardiac magnetic resonance imaging using a clinical 3.0 tesla system

BackgroundTo evaluate the inter-study, inter-reader and intra-reader reproducibility of cardiac cine and scar imaging in rats using a clinical 3.0 Tesla magnetic resonance (MR) system.MethodsThirty-three adult rats (Sprague–Dawley) were imaged 24 hours after surgical occlusion of the left anterior descending coronary artery using a 3.0 Tesla clinical MR scanner (Philips Healthcare, Best, The Netherlands) equipped with a dedicated 70 mm solenoid receive-only coil. Left-ventricular (LV) volumes, mass, ejection fraction and amount of myocardial scar tissue were measured. Intra-and inter-observer reproducibility was assessed in all animals. In addition, repeat MR exams were performed in 6 randomly chosen rats within 24 hours to assess inter-study reproducibility.ResultsThe MR imaging protocol was successfully completed in 32 (97%) animals. Bland-Altman analysis demonstrated high intra-reader reproducibility (mean bias%: LV end-diastolic volume (LVEDV), -1.7%; LV end-systolic volume (LVESV), -2.2%; LV ejection fraction (LVEF), 1.0%; LV mass, -2.7%; and scar mass, -1.2%) and high inter-reader reproducibility (mean bias%: LVEDV, 3.3%; LVESV, 6.2%; LVEF, -4.8%; LV mass, -1.9%; and scar mass, -1.8%). In addition, a high inter-study reproducibility was found (mean bias%: LVEDV, 0.1%; LVESV, -1.8%; LVEF, 1.0%; LV mass, -4.6%; and scar mass, -6.2%).ConclusionsCardiac MR imaging of rats yielded highly reproducible measurements of cardiac volumes/function and myocardial infarct size on a clinical 3.0 Tesla MR scanner system. Consequently, more widely available high field clinical MR scanners can be employed for small animal imaging of the heart e.g. when aiming at serial assessments during therapeutic intervention studies.

Multimodality Management of Vertebral Artery Injury Sustained During Cervical or Craniocervical Surgery

Iatrogenic vertebral artery (VA) injury is a rare but potentially devastating complication associated with cervical and craniocervical surgery. To retrospectively evaluate treatment modalities and outcomes associated with iatrogenic VA injury. Our institutional surgical database was queried for patients who underwent cervical or craniocervical surgery from January 1997 to August 2012. During this time period, 8213 patients underwent cervical or craniocervical surgery, and 17 (0.2%) cases of VA injury were identified. Eight (47%) of these injuries occurred during C1-2 instrumentation procedures. Primary microsurgical repair of the VA was performed in 5 patients. Other cases were managed by either surgical or endovascular VA occlusion. Of the 17 patients, 15 underwent immediate angiography, 9 of whom were ultimately treated by the use of endovascular techniques. VA injury is an uncommon complication of cervical and/or skull base surgery. Standardized management recommendations may help reduce complications associated with these rare but potentially devastating injuries.