Ramp-up of Hawking Radiation in Bose-Einstein-Condensate Analog Black Holes.

Inspired by a recent experiment by Steinhauer and co-workers, we present a simple model which describes the formation of an acoustic black hole in a Bose-Einstein condensate, allowing an analytical computation of the evolution in time of the corresponding density-density correlator. We show the emergence of analog Hawking radiation out of a "quantum atmosphere" region significantly displaced from the horizon. This is quantitatively studied both at T=0 and even in the presence of an initial temperature T, as is always the case experimentally.

Scattering of Co-Current Surface Waves on an Analogue Black Hole.

We report on what is to our knowledge the first scattering experiment of surface waves on an accelerating transcritical flow, which in the analogue gravity context is described by an effective spacetime with a black-hole horizon. This spacetime has been probed by an incident co-current wave, which partially scatters into an outgoing countercurrent wave on each side of the horizon. The measured scattering amplitudes are compatible with the predictions of the hydrodynamical theory, where the kinematical description in terms of the effective metric is exact.

Quantum Backreaction on Three-Dimensional Black Holes and Naked Singularities.

We analytically investigate backreaction by a quantum scalar field on two rotating Bañados-Teitelboim-Zanelli (BTZ) geometries: that of a black hole and that of a naked singularity. In the former case, we explore the quantum effects on various regions of relevance for a rotating black hole space-time. We find that the quantum effects lead to a growth of both the event horizon and the radius of the ergosphere, and to a reduction of the angular velocity, compared to the unperturbed values. Furthermore, they give rise to the formation of a curvature singularity at the Cauchy horizon and show no evidence of the appearance of a superradiant instability. In the case of a naked singularity, we find that quantum effects lead to the formation of a horizon that shields it, thus supporting evidence for the rôle of quantum mechanics as a cosmic censor in nature.

Hepatic colorectal metastases involving infra-hepatic inferior vena cava in high risk patients for extended resection: an alternative method for achieving radical resection in patient with borderline liver remnant.

Resection is the only chance of cure for isolated liver metastases from colorectal cancer. In the case of extended parenchymal resections, one crucial point is the ischemic damage to the remnant liver. We report an alternative technique for extremely extended liver resections without total hilar clamping for borderline liver remnants. Two patients presented with invasion of the infrahepatic vena cava, both with an estimated live remnant ≤20 %. The crucial point of the technique is the absence of a portal triad clamping in under beating heart-extracorporeal circulation. In both patients resection margins were free of disease. No signs of liver insufficiency were noted. Survival was more than 2 years in both cases. We believe that aggressive treatment of liver colorectal metastases should be given to all suitable patients. This operation may be added to the techniques that can be offered to these patients.

Transapical aortic valve implantation in high-risk patients with severe aortic valve stenosis.

BACKGROUND: Transapical aortic valve implantation (TA-TAVI) represents an alternative in patients with symptomatic severe aortic valve stenosis (SSAVS) who cannot be operated on or have a high surgical risk. The aim of this prospective multicenter observational study was to assess early and 2-year clinical and hemodynamic outcomes after TA-TAVI. METHODS: From May 2008 to September 2010, 179 patients with inoperable conditions or high-risk patients underwent TA-TAVI at 4 institutions. Indications for TA-TAVI were SSAVS and logistic EuroSCORE (European System for Cardiac Operative Risk Evaluation) greater than 20% or porcelain aorta in patients with severe aortoiliac disease. Patients underwent clinical and echocardiographic follow-up visits at hospital discharge, 3 and 6 months after TA-TAVI, and every 6 months thereafter. The impact of the learning curve for the centers and of intraoperative complications on patient outcomes was also evaluated. RESULTS: Mean age was 81 ± 6 years. Mean logistic EuroSCORE was 22% ± 12%. Transapical delivery was successful in all patients. Seventeen severe intraoperative complications occurred in 13 (7.3%) patients. Thirty-day mortality was 3.9% (7 patients). Mean follow-up was 9.2 ± 6.5 months. Late mortality occurred in 9 patients. Two-year survival was 88% ± 3%. An intraoperative severe complication was identified as the only significant independent predictor of 1-year mortality. A significant benefit was found when comparing 2-year survival of the second versus the first 50% patients at each center (93% ± 2% versus 84% ± 3 %; p = 0.046). A significant reduction of both mean and peak gradients from the preoperative to the postoperative period, which remained stable during follow-up, was found. CONCLUSIONS: TA-TAVI provides excellent early and 2-year results in terms of survival, valve-related adverse events, and hemodynamic performance. Survival after TA-TAVI is affected by the center learning curve and by the occurrence of an intraoperative complication.

Left ventricular remodeling, hemodynamics and early clinical outcomes after aortic valve replacement with the Pericarbon Freedom stentless bioprosthesis: results from the Italian Prospective Multicenter Trial.

BACKGROUND AND AIM OF THE STUDY: The aims of this multicenter prospective observational trial were to evaluate: (i) the left ventricular remodeling, hemodynamics and early clinical outcomes of patients undergoing aortic valve replacement (AVR) with the Pericarbon Freedom (PF) stentless bioprosthesis; and (ii) the impact of the two suture techniques--continuous and interrupted--on the hemodynamic performance of the bioprosthesis. METHODS: Between November 2001 and April 2004, a total of 226 patients (131 females, 95 males; mean age 73.2 +/- 8.8 years) underwent AVR with the PF valve (Sorin Group, Saluggia, Italy) at eight Italian cardiac surgery centers. Associated surgery was performed in 73 patients (32%); of these operations, 54 were coronary artery bypass grafting. A continuous-suture technique was used in 132 patients (58%), and an interrupted-suture in 90 (40%). The suture technique was not available for four patients. All patients underwent clinical and echocardiographic evaluation immediately before surgery, and at one, six, and 12 months thereafter. The median follow up was 380 days (Q1: 363 days; Q3: 410 days), and the total cumulative follow up 236.9 patient-years (pt-yr). RESULTS: The overall 30-day mortality was 3.5% (n = 8). Late deaths occurred in 10 patients (4%/pt-yr), of which three were valve-related (1%/pt-yr). The overall and valve-related survivals at one year were 92 +/- 2% and 98 +/- 1%, respectively. Freedom from structural valve deterioration, endocarditis, reoperation and thromboembolic events was 100%, 93 +/- 1%, 98 +/- 1% and 99 +/- 1% at one year, respectively. The peak and mean transprosthetic gradients at one year were: 19.7 +/- 12.27 and 8.7 +/- 6.0 mmHg, respectively. After 12 months, significant reductions (compared to preoperative) were observed in the left ventricular mass (148.5 +/- 48.8 versus 194.4 +/- 54.6 g/m2; p < 0.001) and mean wall thickness (1.08 +/- 0.19 versus 1.32 +/- 0.23 cm; p < 0.001). The continuous-suture technique showed a trend towards lower postoperative gradients than did the interrupted-suture technique. CONCLUSION: The data obtained indicated that the PF bioprosthesis provided excellent results in terms of left ventricular mass regression, hemodynamics, and early clinical outcome. Although a trend towards a better hemodynamic performance of the continuous-suture technique was observed, this aspect requires further evaluation.

Clinical and hemodynamic outcomes after aortic valve replacement with stented and stentless pericardial xenografts: a propensity-matched analysis.

BACKGROUND AND AIM OF THE STUDY: Pericardial aortic xenografts have demonstrated excellent durability, and also freedom from tissue failure and from endocarditis. The aim of this single-center propensity-matched study was to compare the clinical and hemodynamic results of aortic valve replacement (AVR) with that for stented and stentless pericardial bioprostheses. METHODS: A total of 111 consecutive AVRs with the Perimount Magna stented valve, performed between December 2002 and December 2007, and 150 consecutive AVRs with the Pericarbon Freedom stentless bioprosthesis, performed between July 1999 and December 2007, was reviewed. Based on a propensity-score analysis, 81 matched pairs were created. The mean age of the 162 patients was 74 +/- 7 years. In total, 31 (38%) and 39 (48%) associated procedures were performed in the stented and stentless groups, respectively (p = 0.20). The mean follow up for stented-valve patients was 20 +/- 9 months (range: 6-35 months), and for stentless-valve patients was 36 +/- 21 months (range: 6-83 months) (p < 0.05). RESULTS: The operative mortality was 4.9% (n = 4) and 6.2% (n = 5) (p = 0.77) in the stented- and stentless-valve groups, respectively. The cumulative actuarial freedom from structural valve deterioration, non-structural dysfunction, reoperation, prosthetic valve endocarditis, hemorrhage and thromboembolic events after 24 months were 98.4 +/- 1.5% and 96.4 +/- 2.6% (p = 0.12) for the stented- and stentless-valve groups, respectively; the actuarial survival rates after 24 months were 82.6 +/- 5.2% and 83.8 +/- 4.3% (p = 0.82), respectively, while freedom from valve-related death was 98.4 +/- 1.5% and 97.2 +/- 1.9% (p = 0.56), respectively. No statistically significant differences were identified between the peak and mean transaortic gradients. CONCLUSION: Both, the stented and stentless pericardial aortic xenografts provided good clinical and hemodynamic results. However, the study results failed to demonstrate any difference regarding early outcomes between the two groups.

RIFLE criteria for cardiac surgery-associated acute kidney injury: risk factors and outcomes.

The aims of this study were to identify risk factors and evaluate the association with clinical outcomes of postoperative cardiac surgery-associated acute kidney injury (CSA-AKI). Data from 2488 consecutive adult patients were analyzed. Patients were classified as having CSA-AKI based on the risk, injury, failure, loss of kidney function, and end-stage kidney disease (RIFLE) criteria using peak postoperative creatinine in the postoperative intensive care unit (ICU). Multiple stepwise logistic regression analysis was used to identify independent risk factors for CSA-AKI. CSA-AKI occurred in 584 patients (23.5%). CSA-AKI patients had significantly longer aortic cross-clamp and cardiopulmonary bypass times. Furthermore, CSA-AKI patients had higher hospital mortality (5.5% vs 1.5%, P<.001) and significantly longer ICU and hospital stays. Independent risk factors for CSA-AKI were age, peripheral vascular disease, hypertension, left ventricular ejection fraction, cardiopulmonary bypass time, and surgery on the thoracic aorta. In conclusion, patients who develop CSA-AKI have a higher preoperative risk profile, more complex surgery, and worse clinical outcomes.

Surgical ventricular reconstruction with different myocardial protection strategies. A propensity matched analysis.

The aim of this study is to compare outcomes of patients undergoing surgical ventricular reconstruction (SVR) with normothermic cardiopulmonary bypass (CPB) and beating heart or hypothermic CPB and cardioplegic arrest. Between 2001 and 2008, 588 patients underwent SVR. A propensity score matching was performed and 91 matched pairs were created: group 1 (G1) operated with normothermic CPB and beating-heart technique, and group 2 (G2) operated with hypothermic CPB and cardioplegic arrest. Mean age was 62+/-9 years in G1 and 63+/-10 years in G2 [not significant (NS)]. Average follow-up was 42.7+/-26 months (range 1-72). Major cardiac and cerebro-vascular events (MACCE) were assessed. Thirty-day mortality was 4% in G1 and 5% in G2 (NS). Kaplan-Meier survival at six years was 79+/-4% and 72+/-9% (NS) and freedom from MACCE was 82+/-4% and 83+/-7% in G1 and G2, respectively (NS). Left ventricular volume reduction, ejection fraction and New York Heart Association (NYHA) class improvement were significant in the overall population; no significant differences were found between groups. The following independent risk factors for cardiac death were identified: mitral valve regurgitation, surgery <3 months from myocardial infarction, NYHA class III-IV. This study showed that outcomes following SVR are not affected by myocardial protection strategies neither in cardiac function and clinical status nor in survival.

Post-traumatic rupture of the anterolateral papillary muscle.

Rupture of cardiac valves as a consequence of nonpenetrating cardiac trauma is an uncommon phenomenon. We report the case of a 24-year-old patient with a "two-stage" traumatic rupture of the anterolateral papillary muscle of the mitral valve, after a blunt chest trauma, who successfully underwent emergency mitral valve replacement.

Guideline for resuscitation in cardiac arrest after cardiac surgery.

The Clinical Guidelines Committee of the European Association for Cardio-Thoracic Surgery provides this professional view on resuscitation in cardiac arrest after cardiac surgery. This document was created using a multimodal methodology for evidence generation including the extrapolation of existing guidelines from the International Liaison Committee on Resuscitation where possible, our own structured literature reviews on issues particular to cardiac surgery, an international survey on resuscitation hosted by CTSNet and manikin simulations of potential protocols. This protocol differs from existing generic guidelines in a number of areas, the most import of which are the following: successful treatment of cardiac arrest after cardiac surgery is a multi-practitioner activity with six key roles that should be allocated and rehearsed on a regular basis; in ventricular fibrillation, three sequential attempts at defibrillation (where immediately available) should precede external cardiac massage; in asystole or extreme bradycardia, pacing (where immediately available) should precede external cardiac massage; where the above measures fail, and in pulseless electrical activity, early resternotomy is advocated; adrenaline should not be routinely given; protocols for excluding reversible airway and breathing complications and for safe emergency resternotomy are given. This guideline is subject to continuous informal review, and when new evidence becomes available.

Endovascular treatment of aberrant right subclavian (lusorian) artery to oesophagus fistula: a case report.

The creation of a fistula between the subclavian artery and the oesophagus is extremely rare. All the reported cases of subclavian oesophagus-arterial fistulae have been described either in aberrant subclavian arteries or as caused by foreign bodies in the oesophagus. In this article, a case of fistulous communication between an aberrant right subclavian and the oesophagus managed with the positioning of endovascular prosthesis is presented.

Guideline on antiplatelet and anticoagulation management in cardiac surgery.

This document presents a professional view of evidence-based recommendations around the issues of antiplatelet and anticoagulation management in cardiac surgery. It was prepared by the Audit and Guidelines Committee of the European Association for Cardio-Thoracic Surgery (EACTS). We review the following topics: evidence for aspirin, clopidogrel and warfarin cessation prior to cardiac surgery; perioperative interventions to reduce bleeding including the use of aprotinin and tranexamic acid; the use of thromboelastography to guide blood product usage; protamine reversal of heparin; the use of factor VIIa to control severe bleeding; anticoagulation after mechanical, tissue valve replacement and mitral valve repair; the use of antiplatelets and clopidogrel after cardiac surgery to improve graft patency and reduce thromboembolic complications and thromboprophylaxis in the postoperative period. This guideline is subject to continuous informal review, and when new evidence becomes available. The formal review date will be at 5 years from publication (September 2013).

Intraoperative coronary angiography in postinfarction ventricular free wall rupture: how technology can change diagnostic and therapeutic timing.

Left ventricular free wall rupture often presents with an abrupt onset and rapidly progresses towards cardiogenic shock or electromechanical dissociation. The diagnostic pathway is still a matter of debate: echocardiography is commonly decisive but the assessment of coronary artery status is essential in order to optimize the surgical procedure. However, a preoperative coronary angiography could generate a dramatic delay of surgery. We report a case of a patient with a post-infarction left ventricular free wall rupture presenting with cardiac tamponade and cardiogenic shock who underwent emergency surgery. After cardiopulmonary bypass institution, an intraoperative coronary angiography was performed. Successful repair of the ventricular free wall rupture associated with a well-targeted surgical myocardial revascularization were carried out. This case illustrates how the development of technologically advanced hybrid operating rooms could lead to a new diagnostic and therapeutic approach to this potentially fatal complication.

Aortic valve replacement with the Sorin Pericarbon Freedom stentless prosthesis: 7 years' experience in 130 patients.

OBJECTIVES: Aortic stentless pericardial valves were introduced into clinical practice to combine properties of both stentless and pericardial prostheses. The aim of this single-center retrospective study was to assess midterm clinical and hemodynamic results of aortic valve replacement with the Sorin Pericarbon Freedom stentless bioprosthesis. METHODS: From July 1999 through November 2005, 130 consecutive patients (73 [56.1%] male patients) underwent aortic valve replacement with the Sorin Pericarbon Freedom bioprosthesis at our institution. Mean age was 76 +/- 5 years (range, 42-86 years), and associated procedures were performed in 50 (38.4%) patients; of these, 41 were coronary artery bypass grafts. Surgical intervention under urgent/emergency conditions and reoperations were performed in 18 (13.8%) and 7 (5.3%) patients, respectively. Mean crossclamp and cardiopulmonary bypass times were 82 +/- 24 and 125 +/- 40 minutes, respectively. All patients underwent clinical and echocardiographic follow-up (100% complete), and the total cumulative follow-up was 324 patient/years (mean, 2.5 +/- 1.8; range, 6 months-7 years). RESULTS: Overall hospital mortality was 8.4%. Overall patient survival was 63% +/- 6% and 50% +/- 10% at 5 and 7 years, respectively. Late deaths occurred in 23 patients, and 6 of them were valve related (1.8% patient/years). Freedom from valve-related death and reoperation was 91% +/- 4% and 94% +/- 4%, respectively, at 7 years. No structural valve deterioration was observed. Endocarditis, thromboembolism, and hemorrhagic complications occurred in 2 (0.6% patient/years), 1 (0.3% patient/years), and 1 (0.3% patient/years) patients, respectively. Mean transprosthetic gradients for valve sizes 23, 25, and 27 were 12.1 +/- 3.8, 10.8 +/- 3.8, and 9 +/- 3.1 mm Hg, respectively. CONCLUSIONS: The Sorin Pericarbon Freedom stentless bioprosthesis provides good early and midterm results in terms of hemodynamic performance, survival, and freedom from valve-related complications.

Long-term results of aortic valve replacement with Edwards Prima Plus stentless bioprosthesis: eleven years' follow up.

BACKGROUND AND AIM OF THE STUDY: The Edwards Lifesciences Prima Plus stentless valve (ELSV) is a bioprosthesis manufactured from a porcine aortic root. The study aim was to evaluate late clinical outcomes after aortic valve replacement (AVR) with ELSV implanted as a miniroot in patients with aortic valve disease. METHODS: Between 1993 and 2004, 318 patients (232 males, 86 females; mean age 69 +/- 9 years; range: 37-83 years) underwent AVR with the ELSV. Preoperatively, 102 patients (32%), 162 (51%) and 54 (17%) were in NYHA classes I/II, III and IV, respectively. Aortic stenosis, aortic regurgitation and combined lesions were present in 124 patients (39%), 114 (36%) and 41 (13%), respectively. Twenty patients (6%) were referred for an acute aortic dissection, 20 (6%) for an aortic root aneurysm, and 139 (44%) had an associated aneurysmal dilatation of the ascending aorta. The ascending aorta was replaced in 159 patients (50%); aortic arch replacement was required in 10 (3%). Coronary artery bypass graft was performed in 86 patients (27%). The follow up was based on clinical data. RESULTS: Operative mortality was 5% (n = 17). There were 49 late deaths (5.2%/pt-yr). Valve-related mortality occurred in 10 patients (1%/pt-yr). Actuarial survival at five and 10 years was 78% and 33%, respectively. Actuarial freedom from valve reoperation and structural valve deterioration at 10 years were 100% and 64%. Actuarial freedom from embolic events and endocarditis at 10 years were 84% and 81%, respectively. CONCLUSION: The ELSV, when implanted as a miniroot, provided good early and long-term results in terms of survival and freedom from major complications.

Repair of ascending aorta pseudoaneurysm without circulatory arrest in redo patient.

A pseudoaneurysm of the ascending aorta is an unusual and potentially fatal complication after aortic surgical operations. TEE and CT scan are the investigations of choice. Surgical treatment is mandatory. We describe the successful management of a pseudoaneurysm of the ascending aorta, with aorto-sternal-cutaneous fistula requiring right axillary and femoral artery cannulation with Remote Access Perfusion(R) aortic cannula (Estech(R), California, USA). Behaving like this we avoid hypotermic circulatory arrest, provide safe reentry and prevent an impending rupture.