The Ross procedure is a safe and durable option in adults with infective endocarditis: a multicentre study

OBJECTIVES

Surgical treatment of infective endocarditis (IE) remains a challenge. The Ross procedure offers the benefit of a living substitute in the aortic position but it is a more complex operation which may lead to increased operative risk. The aim of this study was to assess the safety and late outcomes of the Ross procedure for the treatment of active IE.

METHODS

From 2000 to 2019, a total of 31 consecutive patients underwent a Ross procedure to treat active IE (mean age 43 ± 12 years, 84% male). All patients were followed up prospectively. Four patients (13%) were intravenous (IV) drug users and 6 patients (19%) had prosthetic IE. The most common infective organism was Streptococcus (58%). Median follow-up was 3.5 (0.9-4.5) years and 100% complete.

RESULTS

There were no in-hospital deaths. One patient suffered a postoperative stroke (3%) and 1 patient (3%) required reintervention for bleeding. Three patients had a new occurrence endocarditis: 2 patients were limited to the pulmonary homograft and successfully managed with IV antibiotics, whereas 1 IV drug user patient developed concomitant autograft and homograft endocarditis. Overall, cumulative incidence of IE recurrence was 13 ± 8% at 8 years. The cumulative incidence for autograft endocarditis was 5 ± 4% at 8 years. Two patients (6%) died during follow-up, both from drug overdoses. At 8 years, actuarial survival was 88 ± 8%.

CONCLUSIONS

In selected patients with IE, the Ross procedure is a safe and reasonable alternative with good mid-term outcomes. Freedom from recurrent infection on the pulmonary autograft is excellent, labelporting the notion that a living valve in the aortic position provides good resistance to infection. Nevertheless, in IV drug user patients, pulmonary homograft endocarditis remains a challenge. Continued follow-up is needed to ascertain the long-term benefits of this approach.

Asymptomatic Left Ventricular Malignant Psammomatous Melanotic Schwannoma

Malignant psammomatous melanotic schwannoma (MPMS) is a rare type of tumour, occasionally reported to occur with mediastinal involvement. Histopathologic similarities with melanoma may lead to a wrong diagnosis, but distinguishing between types of tumours is mandatory for adequate management and prognosis. MPMS may be aggressive and manifest unpredictable behavior, with a poor midterm prognosis despite benign histopathologic features. We discuss the challenges that come with a diagnosis of MPMS, and the rationale for our treatment strategy, in this first report regarding MPMS involving the left heart ventricle.

An autopsy view of the Hemi-commando procedure

Invasive endocarditis involving the fibrous skeleton of the heart requires complex high-risk surgical management. For combined aortic and mitral infection in whom the posterior mitral leaflet and at least the free edge of anterior mitral valve could be spared, a modification of the Commando procedure was suggested: the "Hemi-commando procedure." We report the autopsy images of a Hemi-commando procedure after in unfortunate death in a 24 years old man 17 days after surgery.

Large Intramural Aortic Hematoma with Intimal Tear

A 72-year-old man presented with excruciating epigastric pain. A chest computed tomography angiography revealed an aortic intramural hematoma. A filling defect within the distal ascending aorta was noted. Images of an intramular hematoma and surgical details of an ascending aortic replacement under deep hypothermic circulatory arrest are provided.

Identification of Long Noncoding RNA H19 as a New Biomarker and Therapeutic Target in Right Ventricular Failure in Pulmonary Arterial Hypertension

BACKGROUND

Right ventricular (RV) function is the major determinant for both functional capacity and survival in patients with pulmonary arterial hypertension (PAH). Despite the recognized clinical importance of preserving RV function, the subcellular mechanisms that govern the transition from a compensated to a decompensated state remain poorly understood and as a consequence there are no clinically established treatments for RV failure and a paucity of clinically useful biomarkers. Accumulating evidence indicates that long noncoding RNAs are powerful regulators of cardiac development and disease. Nonetheless, their implication in adverse RV remodeling in PAH is unknown.

METHODS

Expression of the long noncoding RNA H19 was assessed by quantitative PCR in plasma and RV from patients categorized as control RV, compensated RV or decompensated RV based on clinical history and cardiac index. The impact of H19 suppression using GapmeR was explored in 2 rat models mimicking RV failure, namely the monocrotaline and pulmonary artery banding. Echocardiographic, hemodynamic, histological, and biochemical analyses were conducted. In vitro gain- and loss-of-function experiments were performed in rat cardiomyocytes.

RESULTS

We demonstrated that H19 is upregulated in decompensated RV from PAH patients and correlates with RV hypertrophy and fibrosis. Similar findings were observed in monocrotaline and pulmonary artery banding rats. We found that silencing H19 limits pathological RV hypertrophy, fibrosis and capillary rarefaction, thus preserving RV function in monocrotaline and pulmonary artery banding rats without affecting pulmonary vascular remodeling. This cardioprotective effect was accompanied by E2F transcription factor 1-mediated upregulation of enhancer of zeste homolog 2. In vitro, knockdown of H19 suppressed cardiomyocyte hypertrophy induced by phenylephrine, while its overexpression has the opposite effect. Finally, we demonstrated that circulating H19 levels in plasma discriminate PAH patients from controls, correlate with RV function and predict long-term survival in 2 independent idiopathic PAH cohorts. Moreover, H19 levels delineate subgroups of patients with differentiated prognosis when combined with the NT-proBNP (N-terminal pro-B-type natriuretic peptide) levels or the risk score proposed by both REVEAL (Registry to Evaluate Early and Long-Term PAH Disease Management) and the 2015 European Pulmonary Hypertension Guidelines.

CONCLUSIONS

Our findings identify H19 as a new therapeutic target to impede the development of maladaptive RV remodeling and a promising biomarker of PAH severity and prognosis.

Right atrial catheter "ghost" removal by cardiac surgery: A pediatric case series report

Fibrin sheath formation around long-term indwelling central venous catheters is common and usually benign. Fibrin sheath can persist after catheter removal and rarely leads to complications. This is a report of three pediatric oncology patients that required cardiac surgery for cardiac embolization of a "ghost" catheter several years after catheter removal. One case required tricuspid valve replacement for complete tricuspid valve destruction and two had erosion through the atrial wall. The severity of these rare complications mandates follow-up of "ghost" catheters in pediatric oncology patients.

Tricuspid Intervention Following Pulmonary Valve Replacement in Adults With Congenital Heart Disease

BACKGROUND

Tricuspid regurgitation (TR) is common among adults with corrected tetralogy of Fallot (TOF) or pulmonary stenosis (PS) referred for pulmonary valve replacement (PVR). Yet, combined valve surgery remains controversial.

OBJECTIVES

This study sought to evaluate the impact of concomitant tricuspid valve intervention (TVI) on post-operative TR, length of hospital stay, and on a composite endpoint consisting of 7 early adverse events (death, reintervention, cardiac electronic device implantation, infection, thromboembolic event, hemodialysis, and readmission).

METHODS

The national Canadian cohort enrolled 542 patients with TOF or PS and mild to severe TR who underwent isolated PVR (66.8%) or PVR+TVI (33.2%). Outcomes were abstracted from charts and compared between groups using multivariable logistic and negative binomial regression.

RESULTS

Median age at reintervention was 35.3 years. Regardless of surgery type, TR decreased by at least 1 echocardiographic grade in 35.4%, 66.9%, and 92.8% of patients with pre-operative mild, moderate, and severe insufficiency. In multivariable analyses, PVR+TVI was associated with an additional 2.3-fold reduction in TR grade (odds ratio [OR]: 0.44; 95% confidence interval [CI]: 0.25 to 0.77) without an increase in early adverse events (OR: 0.85; 95% CI: 0.46 to 1.57) or hospitalization time (incidence rate ratio: 1.17; 95% CI: 0.93 to 1.46). Pre-operative TR severity and presence of transvalvular leads independently predicted post-operative TR. In contrast, early adverse events were strongly associated with atrial tachyarrhythmia, extracardiac arteriopathy, and a high body mass index.

CONCLUSIONS

In patients with TOF or PS and significant TR, concomitant TVI is safe and results in better early tricuspid valve competence than isolated PVR.

P4592Total arterial revascularization in severe coronary artery disease: a 25-years single-center experience

Objective

To evaluate very long-term survival of Total Arterial Revascularization (TAR) in patients with severe coronary artery disease (CAD) undergoing Coronary Artery Bypass Grafting (CABG).

Methods

Between January 1992 and December 2017, 13798 patients aged 70 years or less underwent primary isolated CABG with at least two grafts in our department. Patients receiving TAR were matched by propensity-score analysis to the rest of the population. All pre- and peri-operative data were collected prospectively in our institutional database. Long-term survival was assessed using provincial vital statistics data. The primary outcome was very-long time survival, secondary outcomes were operative mortality and early complications.

Results

Propensity-score matching identified 602 pairs with similar preoperative characteristics. In the matched control group, 65.4% and 30.9% of patients received 1 and 2 arterial grafts, respectively, whereas 3 or more arterial grafts were used in 3.6%. Less distal anastomoses (2.57±0.77 vs 3.39±0.97, p<0.0001) were performed in TAR patients, who therefore had a shorter cross-clamping time (44.2±14.7 vs 52.9±19.6, p<0.0001). Operative mortality was similar (0.5% vs 1.0%, p=0.51) and there was no difference in the rate of mediastinitis (2.5% vs 0.8%, p=0.28)for the TAR and matched control groups, respectively. TAR patients were less likely to receive blood transfusions (34.9% vs 40.7%, p=0.04). The average follow-up was 13.4±6.7 years. Cox-adjusted survival was significantly better in patients receiving TAR compared to the matched population, up to 25 years postoperatively (HR 0.87 [0.86–0.88], p<0.0001, Figure 1).

Figure 1

Conclusion

Total arterial revascularization is not associated with increased perioperative risk of complications and provides long-term survival benefits up to 25 years postoperatively.

Assessing the relevance of carbapenem prescriptions by an antibiotic stewardship team

OBJECTIVES

To assess the level and factors of compliance of carbapenem prescriptions with guidelines and to determine the impact of an antibiotic stewardship team in a university hospital.

PATIENTS AND METHODS

Five-month prospective study in the intensive care, surgery, and medicine units to measure the compliance of carbapenem prescriptions with guidelines from French scientific societies; compliance was assessed by an infectious disease specialist warned by the pharmacy, and the prescribers' compliance with the infectious disease specialist's advice was then assessed.

RESULTS

One hundred and four treatment initiations for 94 patients were included. Prescriptions were mostly empirical (64%), for pulmonary (35%), urinary tract (23%), and intra-abdominal (17%) infections. Prescriptions were mostly made in an intensive care unit (50%), by a junior physician (66%), with the use of imipenem (74%), and were followed by an objective reassessment (80%). Compliance with guidelines (82%) was significantly higher for empirical than documented prescriptions (91% vs 65%, P<0.001). Compliance was higher in intensive care units than medicine units (87% vs 61%, P=0.037). No change in the compliance rate was observed during the study. Compliance with the infectious disease specialist's advice (68%) improved, although not significantly (P=0.066).

CONCLUSIONS

Because of a higher than expected compliance of carbapenem prescriptions with guidelines and a lower than expected inclusions in the study, we did not show any impact. The diffusion of guidelines and long-term control of carbapenem prescriptions seem to be possible and necessary in hospitals to limit their ecological impact.

Neonatal Cardiac Arrest From Left Ventricular Cardiac Hemangioma: A Surprising Presentation

Cardiac hemangioma is rare, even more when leading to a cardiovascular collapse in a seemingly healthy newborn. A 6-day-old neonate had a tamponade caused by a basolateral hemangioma of the left ventricle. Partial surgical resection was performed. A congenital lobular capillary hemangioma was diagnosed upon histologic examination. The patient recovered completely and shows normal development at the 12-month follow-up.

Prosthetic aortic valve thrombosis: To fibrinolyse or not to fibrinolyse? That is the question!

Prosthetic heart valve (PHV) dysfunction is a rare but serious complication whose optimal management may be challenging and requires a multidisciplinary approach. Treatment success ultimately depends on determining the underlying mechanism of valve dysfunction by echocardiography. However, being able to establish the main etiology is not always straightforward. We present a difficult case of obstructive PHV dysfunction and discuss clinical and echocardiographic parameters to help differentiate thrombus from pannus formation.

COMET: a new end-station at SOLEIL for coherent magnetic scattering in transmission

A new instrument named COMET for COherent Magnetic scattering Experiments in Transmission using polarized soft X-rays has been designed and built. This high-vacuum setup is placed at the intermediate focal point of the elastic branch of the SEXTANTS beamline at Synchrotron SOLEIL. The main application is in solid state physics, the instrument being optimized for studying material properties using coherent scattering of soft X-rays with an emphasis on imaging, with chemical selectivity, the magnetic domains of artificially nano-structured materials. The instrument's principal features are presented and illustrated through recently performed experiments.

ÉVALUATION À LONG TERME DES PATIENTS AVEC ANNEAUX VASCULAIRES COMPLETS AU CHU DE QUÉBEC

BACKGROUND

Les anneaux vasculaires complets (AV) sont des anomalies rares des gros vaisseaux. Ils sont souvent symptomatiques en bas âge et nécessitent une chirurgie dans la grande majorité des cas. Les deux formes les plus communes sont les double arc aortique (DAA) et arc aortique droit avec ligament artériel et artère sous-clavière gauches aberrante (AADSCGA). L’approche chirurgicale et la prise en charge à long terme demeurent débattues dans la littérature, en plus, certains patients demeurent symptomatiques après la chirurgie.

OBJECTIVES

Évaluation à long terme des patients opérés pour un AV.

DESIGN/METHODS

Étude rétrospective observationnelle des patients diagnostiqués avec un AV.

RESULTS

Soixante-six patients ont été diagnostiqués avec un AV (16 patients avec DAA et 50 avec AADSCGA +/- diverticule de Kommerell (DK)). Au diagnostic, 61% étaient symptomatiques (39% symptômes respiratoires, 27% symptômes digestifs hauts, 6% les deux), alors que 20% ont été diagnostiqués dans le cadre d’une anomalie cardiaque associée; chez les autres, il s’agissait d’une découverte fortuite. Trente-huit pourcent des patients avaient une anomalie cardiaque associée. Vingt-trois pourcent des patients avaient un syndrome génétique, dont 53% étaient des syndromes de DiGeorge. Douze patients ont eu un diagnostic concomitant de trachéomalacie. Les patients avec DAA ont été diagnostiqués plus tôt (1.8 ± 3.6 vs 5 ± 8.3 ans, p=0.038) et opérés plus précocement après le diagnostic (82 ± 123 vs 264 ± 416 jours, p=0.036) que les patients avec AADSCGA. Une chirurgie a été effectuée chez 67% des cas, avec 34 patients (77%) subissant une division avec aortopexie. Aucun patient n’est décédé des suites de sa chirurgie. Deux patients ont dû avoir une seconde chirurgie pour des symptômes secondaires à l’AV. Au dernier suivi, 16 patients demeuraient symptomatiques au niveau respiratoire (aucun symptôme digestif), dont 9 patients opérés (20%). Sept patients ont eu une investigation supplémentaire par spirométrie, par contre, aucun n’a eu d’imagerie additionnelle.

CONCLUSION

Les AV sont des anomalies rares et se présentent habituellement dans la première année de vie. Une chirurgie est généralement curatrice et sécuritaire. Néanmoins, plusieurs patients opérés demeurent symptomatiques au dernier suivi. Il serait probablement judicieux d’investiguer ces patients par imagerie pour préciser la cause de la symptomatologie résiduelle.

Association of prenatal exposure to gestational diabetes with offspring body composition and regional body fat distribution

The aim of this cohort study was to compare body composition and regional body fat distribution between children exposed (GDM+) or unexposed (GDM-) in utero to gestational diabetes mellitus (GDM) and to investigate the association with the glycaemic and the insulin profile. Data from 56 GDM+ and 30 GDM- were analysed. Height, weight and waist circumference were measured. Total and regional body composition was measured by dual-energy X-ray absorptiometry. Insulin, glucose and HbA_1c were obtained from a fasting plasma sample, and the HOMA-IR index was calculated. anova was performed to compare adiposity measures between GDM+ and GDM-. Associations between the glycaemic and insulin profile and adiposity measures were studied using partial Pearson correlations. Mean age was 6.6 ± 2.3 years. Waist circumference, fat mass percentage, android fat mass, android fat mass percentage and android-to-gynoid fat mass ratio were higher among GDM+, and lean mass percentage was lower (P < 0.05). Among GDM+ children, body mass index (BMI) z score, waist circumference, fat mass percentage, android fat mass percentage and android-to-gynoid fat mass ratio were all positively correlated with HbA_1C (r = 0.32-0.43, P < 0.05). Prenatal exposure to GDM is associated with increased total and abdominal adiposity. This increased adiposity observed among GDM+ children is associated with an altered glycaemic profile. This study is registered in the Clinical Trials.gov registry (NCT01340924).

Anomalous Left Coronary Artery From the Pulmonary Artery: Masquerading as Peripartum Cardiomyopathy

Diagnosed with peripartum cardiomyopathy 8 years earlier, a 45-year-old woman had sudden cardiac death. After resuscitation, the patient was diagnosed with an anomalous origin of the left coronary artery from the pulmonary artery and underwent a successful coronary repair. The management of a patient with clinical features of cardiomyopathy is reviewed.

Clinical Outcomes Following the Ross Procedure in Adults: A 25-Year Longitudinal Study

BACKGROUND

Very few reports of long-term outcomes of patients who underwent the Ross procedure have been published.

OBJECTIVES

The authors reviewed their 25-year experience with the Ross procedure with the aim of defining very-long-term survival and factors associated with Ross-related failure.

METHODS

Between January 1990 and December 2014, the Ross procedure was performed in 310 adults (mean age 40.8 years) at a single institution. All patients were prospectively added to a dedicated cardiac surgery registry. Complete post-operative clinical examination and history were obtained, and transthoracic echocardiography was performed according to a standardized protocol. There was no loss to follow-up. Median follow-up was 15.1 years and up to 25 years.

RESULTS

Bicuspid aortic valve was diagnosed in 227 patients (73.2%), and the most common indication for surgery was aortic stenosis (n = 225 [72.6%]). Freedom from any Ross-related reintervention was 92.9% and 70.1% at 10 and 20 years, respectively. Independent risk factors for pulmonary autograft degeneration were pre-operative large aortic annulus (hazard ratio: 1.1; p = 0.01), pre-operative aortic insufficiency (hazard ratio: 2.7; p = 0.002), and concomitant replacement of the ascending aorta (hazard ratio: 7.7; p = 0.0003). There were 4 hospital deaths (1.3%), and overall survival at 10 and 20 years was 94.1% and 83.6%, respectively. Long-term survival was not significantly different in patients who required Ross-related reintervention (log-rank p = 0.70). However, compared with the general population, survival was significantly lower in patients following the Ross procedure when matched on age and sex (p < 0.0001).

CONCLUSIONS

The Ross procedure was associated with excellent long-term valvular outcomes and survival, regardless of the need for reintervention. Adults presenting with aortic insufficiency or a dilated aortic annulus or ascending aorta were at greater risk for reintervention. Unlike previous reports, long-term survival was lower in Ross patients compared with matched subjects.

Thermodynamic phase transitions in a frustrated magnetic metamaterial

Materials with interacting magnetic degrees of freedom display a rich variety of magnetic behaviour that can lead to novel collective equilibrium and out-of-equilibrium phenomena. In equilibrium, thermodynamic phases appear with the associated phase transitions providing a characteristic signature of the underlying collective behaviour. Here we create a thermally active artificial kagome spin ice that is made up of a large array of dipolar interacting nanomagnets and undergoes phase transitions predicted by microscopic theory. We use low energy muon spectroscopy to probe the dynamic behaviour of the interacting nanomagnets and observe peaks in the muon relaxation rate that can be identified with the critical temperatures of the predicted phase transitions. This provides experimental evidence that a frustrated magnetic metamaterial can be engineered to admit thermodynamic phases.

Downregulation of MicroRNA-126 Contributes to the Failing Right Ventricle in Pulmonary Arterial Hypertension

BACKGROUND

Right ventricular (RV) failure is the most important factor of both morbidity and mortality in pulmonary arterial hypertension (PAH). However, the underlying mechanisms resulting in the failed RV in PAH remain unknown. There is growing evidence that angiogenesis and microRNAs are involved in PAH-associated RV failure. We hypothesized that microRNA-126 (miR-126) downregulation decreases microvessel density and promotes the transition from a compensated to a decompensated RV in PAH.

METHODS AND RESULTS

We studied RV free wall tissues from humans with normal RV (n=17), those with compensated RV hypertrophy (n=8), and patients with PAH with decompensated RV failure (n=14). Compared with RV tissues from patients with compensated RV hypertrophy, patients with decompensated RV failure had decreased miR-126 expression (quantitative reverse transcription-polymerase chain reaction; P<0.01) and capillary density (CD31(+) immunofluorescence; P<0.001), whereas left ventricular tissues were not affected. miR-126 downregulation was associated with increased Sprouty-related EVH1 domain-containing protein 1 (SPRED-1), leading to decreased activation of RAF (phosphorylated RAF/RAF) and mitogen-activated protein kinase (MAPK); (phosphorylated MAPK/MAPK), thus inhibiting the vascular endothelial growth factor pathway. In vitro, Matrigel assay showed that miR-126 upregulation increased angiogenesis of primary cultured endothelial cells from patients with decompensated RV failure. Furthermore, in vivo miR-126 upregulation (mimic intravenous injection) improved cardiac vascular density and function of monocrotaline-induced PAH animals.

CONCLUSIONS

RV failure in PAH is associated with a specific molecular signature within the RV, contributing to a decrease in RV vascular density and promoting the progression to RV failure. More importantly, miR-126 upregulation in the RV improves microvessel density and RV function in experimental PAH.

Study of the role of cytosolic phospholipase A2 alpha in eicosanoid generation and thymocyte maturation in the thymus

The thymus is a primary lymphoid organ, home of maturation and selection of thymocytes for generation of functional T-cells. Multiple factors are involved throughout the different stages of the maturation process to tightly regulate T-cell production. The metabolism of arachidonic acid by cyclooxygenases, lipoxygenases and specific isomerases generates eicosanoids, lipid mediators capable of triggering cellular responses. In this study, we determined the profile of expression of the eicosanoids present in the mouse thymus at different stages of thymocyte development. As the group IVA cytosolic phospholipase A₂ (cPLA₂α) catalyzes the hydrolysis of phospholipids, thereby generating arachidonic acid, we further verified its contribution by including cPLA₂α deficient mice to our investigations. We found that a vast array of eicosanoids is expressed in the thymus, which expression is substantially modulated through thymocyte development. The cPLA₂α was dispensable in the generation of most eicosanoids in the thymus and consistently, the ablation of the cPLA₂α gene in mouse thymus and the culture of thymuses from human newborns in presence of the cPLA₂α inhibitor pyrrophenone did not impact thymocyte maturation. This study provides information on the eicosanoid repertoire present during thymocyte development and suggests that thymocyte maturation can occur independently of cPLA₂α.

Detection and quantification of microparticles from different cellular lineages using flow cytometry. Evaluation of the impact of secreted phospholipase A2 on microparticle assessment

Microparticles, also called microvesicles, are submicron extracellular vesicles produced by plasma membrane budding and shedding recognized as key actors in numerous physio(patho)logical processes. Since they can be released by virtually any cell lineages and are retrieved in biological fluids, microparticles appear as potent biomarkers. However, the small dimensions of microparticles and soluble factors present in body fluids can considerably impede their quantification. Here, flow cytometry with improved methodology for microparticle resolution was used to detect microparticles of human and mouse species generated from platelets, red blood cells, endothelial cells, apoptotic thymocytes and cells from the male reproductive tract. A family of soluble proteins, the secreted phospholipases A₂ (sPLA₂), comprises enzymes concomitantly expressed with microparticles in biological fluids and that catalyze the hydrolysis of membrane phospholipids. As sPLA₂ can hydrolyze phosphatidylserine, a phospholipid frequently used to assess microparticles, and might even clear microparticles, we further considered the impact of relevant sPLA2 enzymes, sPLA2 group IIA, V and X, on microparticle quantification. We observed that if enriched in fluids, certain sPLA₂ enzymes impair the quantification of microparticles depending on the species studied, the source of microparticles and the means of detection employed (surface phosphatidylserine or protein antigen detection). This study provides analytical considerations for appropriate interpretation of microparticle cytofluorometric measurements in biological samples containing sPLA2 enzymes.

Nano-micro structured superhydrophobic zinc coating on steel for prevention of corrosion and ice adhesion

Thin films of zinc have been deposited on steel substrates by electrodeposition process and further functionalized with ultra-thin films of commercial silicone rubber, in order to obtain superhydrophobic properties. Morphological feature, by scanning electron microscope (SEM), shows that the electrodeposited zinc films are composed of micro-nano rough patterns. Furthermore, chemical compositions of these films have been analyzed by X-ray diffraction (XRD) and infra-red (IRRAS). An optimum electrodeposition condition, based on electrical potential and deposition time, has been obtained which provides superhydrophobic properties with a water contact angle of 155±1°. The corrosion resistance properties, in artificial seawater, of the superhydrophobic zinc coated steel are found to be superior to bare steel. Similarly, the measured ice adhesion strength on superhydrophobic surfaces, using the centrifugal adhesion test (CAT), is found to be 6.3 times lower as compared to bare steel. This coating has promising applications in offshore environment, to mitigate corrosion and reduce ice adhesion.

Surgical lead extraction for total occlusion of the superior vena cava by chronic lead infection after mustard procedure

We present a case of total occlusion of the superior vena cava (SVC) with extensive thrombosis of the adjacent large veins secondary to multiple abandoned pacemaker leads with a superimposed chronic lead infection by Corynebacterium jeikeium. A surgical lead extraction was performed with an extensive en-bloc resection of the SVC together with the right subclavian vein and the right innomate vein. No venous reconstruction was required because of an unobstructed runoff via a well-developed azygos system.

Direct observation of thermal relaxation in artificial spin ice

We study the thermal relaxation of artificial spin ice with photoemission electron microscopy, and are able to directly observe how such a system finds its way from an energetically excited state to the ground state. On plotting vertex-type populations as a function of time, we can characterize the relaxation, which occurs in two stages, namely a string and a domain regime. Kinetic Monte Carlo simulations agree well with the temporal evolution of the magnetic state when including disorder, and the experimental results can be explained by considering the effective interaction energy associated with the separation of pairs of vertex excitations.

Long-Term Clinical and Echocardiographic Follow-Up of the Freestyle Stentless Aortic Bioprosthesis

Background—

Stentless aortic bioprostheses were designed to provide enhanced hemodynamic performance and potentially greater longevity. The present report describes the outcomes of patients with the Freestyle stentless bioprosthesis followed for ≤18 years.

Methods and Results—

Between 1993 and 2011, 430 patients underwent primary aortic valve replacement with a Freestyle bioprosthesis in the subcoronary position. Mean age was 68.2±8.2 years. All of the clinical and echocardiographic data were collected prospectively. Mean overall follow-up was 9.1±4.4 years and was complete in all of the patients. In-hospital mortality was 3.5% (n=15). Overall, 10- and 15-year survival were 60.7% and 35.0%, respectively. Fifty-one patients required reoperation during follow-up, including 27 for structural valve deterioration (SVD). Overall, freedom from reoperation was 91.0% and 75.0% at 10 and 15 years, whereas freedom from reoperation for SVD was 95.9% and 82.3%, respectively. At 10 and 15 years, freedom from reoperation for SVD was 94.0% and 62.6% for patients <60 years of age and 96.3% and 88.4% for patients ≥60 years of age ( P =0.002). The median time to explant for SVD was 10.7 years. SVD presented mostly as acute, severe aortic insufficiency attributed to leaflet tear (77.8%). The independent risk factors for reoperation for SVD were age <60 years ( P =0.001) and dyslipidemia ( P =0.02).

Conclusions—

Aortic valve replacement with the Freestyle bioprosthesis in a subcoronary position provides good long-term clinical and echocardiographic outcomes for patients >60 years of age. Severe aortic insufficiency with leaflet tear is the major mode of SVD leading to reoperation in these patients.

Sudden cardiac arrest due to subtotal absence of left-sided pericardium--case report and review of the literature

Congenital absence of the pericardium is a very rare cardiac malformation, usually diagnosed fortuitously on autopsy or surgery. Symptoms related to these abnormalities are usually benign, and fatalities reported in the literature are almost exclusively secondary to herniation of the heart through a partial defect. We present the unusual case of a 44-year-old woman admitted for sudden cardiac arrest. Initial evaluation suggested acute anterior myocardial infarction, but further investigation ruled out coronary heart disease. No arrhythmia could be initiated on electrophysiological study, and absence of most of the left pericardium was confirmed by cardiac magnetic resonance imaging. After the exclusion of common etiologies such as idiopathic ventricular fibrillation, transient great vessel torsion due to hypermobility of the heart with secondary malignant arrhythmia was considered to be the most likely mechanism for the sudden cardiac arrest. A review of the available literature on clinical presentation, diagnostic tools, and therapeutic options is also presented.