Inter-atrial septal balloon dilation to facilitate intracardiac echocardiography guided left atrial appendage occlusion.

INTRODUCTION: Percutaneous left atrial appendage occlusion (LAAO) is traditionally performed under general anesthesia with trans-esophageal echocardiography guidance. Intracardiac echo (ICE)-guided LAAO closure is increasing in clinical use. The ICE catheter is crossed into LA via interatrial septum (IAS) after the septum is dilated with LAAO delivery sheath. This step can be time-consuming and requires significant ICE catheter manipulation, which increases the risk of cardiac perforation. Pre-emptive septal balloon dilation can potentially help with ICE advancement in the LA. We sought to evaluate the effect of pre-dilation of the IAS with an 8 mm balloon on the ease of crossing the ICE catheter, fluoroscopy time for crossing, and overall procedure time. METHODS: The Piedmont LAAO registry was used to identify consecutive patients who underwent LAAO. The initial 25 patients in whom balloon dilation of the IAS was performed served as the experimental cohort, and the 25 consecutive patients before that in whom balloon dilation was not performed served as controls. In the experimental group, after a trans-septal puncture, the sheath was retracted to the right atrium with a guidewire still in the LA. An 8 × 40 mm Evercoss™ over the wire balloon was inflated across the IAS. The ICE catheter was then crossed into the LA using the fluoroscopic landmark of the guide wire and the ICE imaging. The sheath was then advanced along the ICE catheter via the transseptal puncture (TSP) and the procedure continued. Follow-up compputed tomography imaging was obtained at 4-8 weeks. RESULTS: Each group consisted of 25 patients. There were no significant differences in baseline characteristics. All procedures were performed successfully under conscious sedation and ICE guidance. There was a significant reduction in the overall procedure time, fluoroscopy time, and time for transseptal puncture to ICE in LA. There was no difference in the size of the acute residual interatrial shunt, as measured via ICE, or the size and presence of iatrogenic ASD at follow-up. CONCLUSION: Balloon dilation of TSP is safe and is associated with increased efficiency in ICE-guided LAAO procedures.

Atrial fibrillation ablation in heart failure patients: Where do we stand in 2023? - State of the art review.

Atrial fibrillation (AF) and heart failure are common overlapping cardiovascular disorders. Despite important therapeutic advances over the past several decades, controversy persists about whether a rate control or rhythm control approach constitutes the best option in this population. There is also considerable debate about whether antiarrhythmic drug therapy or ablation is the best approach when rhythm control is pursued.  A brief historical examination of the literature addressing this issue will be performed. An analysis of several important clinical outcomes observed in the prospective, randomized studies, which have compared AF ablation to non-ablation treatment options, will be discussed. This review will conclude with recommendations to guide clinicians on the status of AF ablation as a treatment option when considering management options in heart failure patients with atrial fibrillation.

Polarization selective Dove prism.

We propose a passive all optical device capable of transforming the orbital angular momentum (OAM) state of light conditioned over the polarization states. The efficiency of this device is ensured due to its linear optical nature. As applications of this device, we show CNOT and SWAP operations between polarization and OAM qubits, non-interferometric OAM mode sorter and generalized Pauli X operation on a four-dimensional subspace of OAM.

Detecting Acceleration-Enhanced Vacuum Fluctuations with Atoms Inside a Cavity.

Some of the most prominent theoretical predictions of modern times, e.g., the Unruh effect, Hawking radiation, and gravity-assisted particle creation, are supported by from the fact that various quantum constructs like particle content and vacuum fluctuations of a quantum field are observer-dependent. Despite being fundamental in nature, these predictions have not yet been experimentally verified because one needs extremely strong gravity (or acceleration) to bring them within the existing experimental resolution. In this Letter, we demonstrate that a post-Newtonian rotating atom inside a far-detuned cavity experiences strongly modified quantum fluctuations in the inertial vacuum. As a result, the emission rate of an excited atom gets enhanced significantly along with a shift in the emission spectrum due to the change in the quantum correlation under rotation. We propose an optomechanical setup that is capable of realizing such acceleration-induced particle creation with current technology. This provides a novel and potentially feasible experimental proposal for the direct detection of noninertial quantum field theoretic effects.

Detecting Topological Transitions in Two Dimensions by Hamiltonian Evolution.

We show that the evolution of two-component particles governed by a two-dimensional spin-orbit lattice Hamiltonian can reveal transitions between topological phases. A kink in the mean width of the particle distribution signals the closing of the band gap, a prerequisite for a quantum phase transition between topological phases. Furthermore, for realistic and experimentally motivated Hamiltonians, the density profile in topologically nontrivial phases displays characteristic rings in the vicinity of the origin that are absent in trivial phases. The results are expected to have an immediate application to systems of ultracold atoms and photonic lattices.

Comparative outcomes of transvenous extraction of sprint fidelis and riata defibrillator leads: a single center experience.

INTRODUCTION: The FDA has issued class I advisories for Medtronic Sprint Fidelis(®) and St. Jude Medical Riata(TM) ICD lead families. Transvenous Riata(TM) ICD lead extraction is typically considered higher risk than Fidelis(®) extraction, based on longer duration from implant, presence of externalized conductors and lack of silicone backfill in the SVC and RV coils. However, published data comparing procedural outcomes between these leads are limited. METHODS: Records were reviewed for all patients undergoing transvenous extraction of Sprint Fidelis(®) or Riata(TM) ICD leads at the Vanderbilt Heart and Vascular Institute from July 2006 to April 2013 to ascertain indication for extraction, procedural details, complications, and 30-day mortality. RESULTS: There were significant differences between those undergoing extraction of a Sprint Fidelis(®) (n = 145) or Riata(TM) lead (n = 47). In the Riata(TM) group, device-related endocarditis was a more common indication for extraction, the mean duration of implant was longer, and larger excimer laser sheaths were required. Lead malfunction was a more common indication in the Fidelis(®) group. There were no statistically significant differences in median procedure duration, procedural success (97.9% vs 95.7%, P = 0.41), median length of hospital stay (1 day vs 1 day, P = 0.23), procedural complication rate (5.5% vs 10.6%, P = 0.23) or 30-day mortality (2.1% vs 2.1%, P = 0.98). Analyses excluding patients with device infection revealed similar results. CONCLUSION: Despite differences in baseline characteristics, this study indicates that Medtronic Sprint Fidelis(®) and St. Jude Riata(TM) ICD leads have similar procedural outcomes with transvenous lead extraction.

High-risk lead removal by planned sequential transvenous laser extraction and minimally invasive right thoracotomy.

INTRODUCTION: Transvenous pacemaker or implantable cardioverter defibrillator (ICD) lead extraction via mechanical or excimer laser sheath is typically safe and effective. Longer duration from implant, presence of large vegetations or thrombi, fractured leads, and prior failed extraction are risk factors predicting higher complication rates or incomplete or failed lead removal. Techniques developed for minimally invasive valve surgery were used in conjunction with laser extraction to refine a "hybrid" technique for lead extraction. We assessed the outcomes of high-risk lead extraction using this hybrid lead extraction technique. METHODS AND RESULTS: Retrospective assessment of clinical parameters and procedural outcomes in patients undergoing planned hybrid lead extraction from February 2008 to September 2012 was performed. We report 8 cases of hybrid lead extraction performed at our institution. We extracted 21 leads with average lead age of 13.8 years since implant. All leads were removed with complete clinical and radiographic success. There were no intraprocedure complications. One patient died of continued sepsis and 1 other had symptoms consistent with pulmonary embolism. CONCLUSIONS: Hybrid lead extraction using this technique is a safe and effective approach for removal of high-risk chronic pacemaker or ICD leads. This method extends the range of approachable leads resulting in complete removal without median sternotomy. Hybrid lead extraction can be scheduled electively facilitating complete lead removal with a low complication rate and short postoperative recovery time, mitigating the risks inherent in midline sternotomy or emergent cardiac surgical rescue.

Real-world data of radiofrequency catheter ablation in paroxysmal atrial fibrillation: Short- and long-term clinical outcomes from the prospective multicenter REAL-AF Registry.

BACKGROUND: The safety and long-term efficacy of radiofrequency (RF) catheter ablation (CA) of paroxysmal atrial fibrillation (PAF) has been well established. Contemporary techniques to optimize ablation delivery, reduce fluoroscopy use, and improve clinical outcomes have been developed. OBJECTIVE: The purpose of this study was to assess the contemporary real-world practice approach and short and long-term outcomes of RF CA for PAF through a prospective multicenter registry. METHODS: Using the REAL-AF (Real-world Experience of Catheter Ablation for the Treatment of Symptomatic Paroxysmal and Persistent Atrial Fibrillation; ClincalTrials.gov Identifier: NCT04088071) Registry, patients undergoing RF CA to treat PAF across 42 high-volume institutions and 79 experienced operators were evaluated. The procedures were performed using zero or reduced fluoroscopy, contact force sensing catheters, wide area circumferential ablation, and ablation index as a guide with a target of 380-420 for posterior and 500-550 for anterior lesions. The primary efficacy outcome was freedom from all-atrial arrhythmia recurrence at 12 months. RESULTS: A total of 2470 patients undergoing CA from January 2018 to December 2022 were included. Mean age was 65.2 ±11.14 years, and 44% were female. Most procedures were performed without fluoroscopy (71.5%), with average procedural and total RF times of 95.4 ± 41.7 minutes and 22.1±11.8 minutes, respectively. At 1-year follow-up, freedom from all-atrial arrhythmias was 81.6% with 89.7% of these patients off antiarrhythmic drugs. No significant difference was identified comparing pulmonary vein isolation vs pulmonary vein isolation plus ablation approaches. The complication rate was 1.9%. CONCLUSION: Refinement of RF CA to treat PAF using contemporary tools, standardized protocols, and electrophysiology laboratory workflows resulted in excellent short- and long-term clinical outcomes.

Embolization of percutaneous left atrial appendage closure devices: Timing, management and clinical outcomes.

BACKGROUND: Left atrial appendage (LAA) occluder embolization is an infrequent but serious complication. OBJECTIVES: We aim to describe timing, management and clinical outcomes of device embolization in a multi-center registry. METHODS: Patient characteristics, imaging findings and procedure and follow-up data were collected retrospectively. Device embolizations were categorized according to 1) timing 2) management and 3) clinical outcomes. RESULTS: Sixty-seven centers contributed data. Device embolization occurred in 108 patients. In 70.4 % of cases, it happened within the first 24 h of the procedure. The device was purposefully left in the LA and the aorta in two (1.9 %) patients, an initial percutaneous retrieval was attempted in 81 (75.0 %) and surgery without prior percutaneous retrieval attempt was performed in 23 (21.3 %) patients. Two patients died before a retrieval attempt could be made. In 28/81 (34.6 %) patients with an initial percutaneous retrieval attempt a second, additional attempt was performed, which was associated with a high mortality (death in patients with one attempt: 2.9 % vs. second attempt: 21.4 %, p < 0.001). The primary outcome (bailout surgery, cardiogenic shock, stroke, TIA, and/or death) occurred in 47 (43.5 %) patients. Other major complications related to device embolization occurred in 21 (19.4 %) patients. CONCLUSIONS: The majority of device embolizations after LAA closure occurs early. A percutaneous approach is often the preferred method for a first rescue attempt. Major adverse event rates, including death, are high particularly if the first retrieval attempt was unsuccessful. CONDENSED ABSTRACT: This dedicated multicenter registry examined timing, management, and clinical outcome of device embolization. Early embolization (70.4 %) was most frequent. As a first rescue attempt, percutaneous retrieval was preferred in 75.0 %, followed by surgical removal (21.3 %). In patients with a second retrieval attempt a higher mortality (death first attempt: 2.9 % vs. death second attempt: 24.1 %, p < 0.001) was observed. Mortality (10.2 %) and the major complication rate after device embolization were high.

Lead thrombi associated with externalized cables on Riata ICD leads: a case series.

St. Jude Riata family ICD leads are subject to an FDA class I recall due to insulation failure, cable extrusions, and a high rate of electrical failures. We present multiple cases of large intravascular thrombus formation adherent to externalized conductor cables on Riata leads. Our observations highlight a previously unknown risk of large or calcified thrombus formation involving externalized conductors. We suggest that these leads should be screened for thrombi prior to potential lead extraction to determine the safest approach. Serial echocardiography may help detect progressive thrombus formation. The role of systemic anticoagulation for prevention or treatment of these thrombi remains unclear.

Implementing quantum walks using orbital angular momentum of classical light.

We present an implementation scheme for a quantum walk in the orbital angular momentum space of a laser beam. The scheme makes use of a ring interferometer, containing a quarter-wave plate and a q plate. This setup enables one to perform an arbitrary number of quantum walk steps. In addition, the classical nature of the implementation scheme makes it possible to observe the quantum walk evolution in real time. We use nonquantum entanglement of the laser beam's polarization with its orbital angular momentum to implement the quantum walk.

Stable algebraic spin liquid in a Hubbard model.

We show the existence of a stable algebraic spin liquid (ASL) phase in a Hubbard model defined on a honeycomb lattice with spin-dependent hopping that breaks time-reversal symmetry. The effective spin model is the Kitaev model for large on-site repulsion. The gaplessness of the emergent Majorana fermions is protected by the time-reversal invariance of this model. We prove that the effective spin model is time-reversal invariant in the entire Mott phase, thus ensuring the stability of the ASL. The model can be physically realized in cold atom systems, and we propose experimental signals of the ASL.

Comparison of intravenous terlipressin infusion versus bolus in patients with acute-on-chronic liver failure-acute kidney injury - an open label RCT.

Aim of the study: Despite having ample literature in hepatorenal syndrome-acute kidney injury (HRS-AKI) in decompensated cirrhosis patients, there is a scarcity of data on acute-on-chronic liver failure-acute kidney injury (ACLF-AKI). We compared terlipressin infusion with bolus in ACLF-AKI patients. Material and methods: Patients with ACLF (as per the CANONIC study) were screened for AKI as per the 2015 ICA-AKI criteria. If after 48 h of volume expansion with albumin, serum creatinine (sCr) did not improve, patients were randomized into two groups: Terli-infusion (Terli-I) 2 mg/day and Terli-bolus (Terli-B) 1 mg q6h. If sCr did not decrease < 25% of pretreatment value after 48 h, the terlipressin dose was increased to a maximum of 12 mg/day. The primary outcome was taken as regression (full or partial response), stable/no response and progression of AKI to higher stages and secondary outcomes were taken as 28-day and 90-day mortality. Results: After screening 136 patients with ACLF-AKI, Terli-I (n = 50) and Terli-B (n = 50) with mean sCr 2.4 and 2.1 mg/dl respectively were enrolled. The regression of AKI (full response 37 vs. 27, partial response 3 vs. 9, p = 0.5), stable (2 vs. 5, p = 0.6), progression of AKI (8 vs. 7, p = 0.2) were present in Terli-I and Terli-B respectively. No significant difference was found in 28-and 90-day mortality. In Terli-B, mean terlipressin dose was 8 vs. 4 mg, p < 0.008 with more side effects, 15 vs. 0, p < 0.01 than Terli-I respectively. Conclusions: Terlipressin infusion is more effective than bolus doses in regression of acute kidney injury and better tolerated in acute-on-chronic liver failure-AKI patients.

Isoproterenol-Assisted Differentiation Between Sludge and Organized Thrombus to Guide Left Atrial Appendage Occlusion.

Percutaneous left atrial appendage occlusion (LAAO) is contraindicated in presence of left atrial appendage (LAA) thrombus. It is often difficult to separate LAA sludge from an organized thrombus on transesophageal echocardiography. The inability to differentiate sludge from thrombus leads to patients not receiving LAAO despite contraindication to long-term anticoagulation. Retrospective 6-month follow-up outcomes are reported on patients undergoing LAAO in presence of LAA sludge cleared by isoproterenol. This study showed no increased risk of transient ischemic attack/stroke in the 6 months following LAAO in the presence of LAA sludge, which was cleared with isoproterenol. This study suggests a role for isoproterenol in differentiating sludge from thrombus.

Studying the effect of fluctuating environment on intra-atomic frequency comb based quantum memory.

In this article, we study the effect of various environmental factors on intra-atomic frequency comb (I-AFC) based quantum memory. The effect of the environment is incorporated as random fluctuations and non-uniformity in the parameters such as comb spacing and the optical depth, of the frequency comb. We found that the I-AFC is viable for photon storage even for very large fluctuations in the parameters of the frequency comb, which makes I-AFC a robust platform for photon storage. Furthermore, we show that the non-uniform frequency combs without any fluctuations in the comb parameters can also yield efficient quantum memory. Since the intra-atomic frequency combs found in natural atomic systems are often non-uniform, our results suggest that a large class of these systems can be used for I-AFC based efficient quantum memory.

Persistence of topological phases in non-Hermitian quantum walks.

Discrete-time quantum walks are known to exhibit exotic topological states and phases. Physical realization of quantum walks in a lossy environment may destroy these phases. We investigate the behaviour of topological states in quantum walks in the presence of a lossy environment. The environmental effects in the quantum walk dynamics are addressed using the non-Hermitian Hamiltonian approach. We show that the topological phases of the quantum walks are robust against moderate losses. The topological order in one-dimensional split-step quantum walk persists as long as the Hamiltonian respects exact [Formula: see text]-symmetry. Although the topological nature persists in two-dimensional quantum walks as well, the [Formula: see text]-symmetry has no role to play there. Furthermore, we observe topological phase transition in two-dimensional quantum walks that is induced by losses in the system.

Implantable defibrillators improve survival in end-stage renal disease: results from a multi-center registry.

BACKGROUND: Small retrospective analyses suggest that end-stage renal disease (ESRD) patients do not obtain as much of a survival benefit from an implantable cardioverter-defibrillator (ICD) as non-ESRD patients do. We aimed to assess the survival effect of an ICD in ESRD patients with left ventricular dysfunction. METHODS: Data from two registries identified ESRD patients with an ICD and ESRD patients with left ventricular dysfunction (defined as ejection fraction <0.35). Cox proportional hazards regression was performed, including certain predefined covariates to assess the effect of an ICD on survival. RESULTS: Overall survival in the full cohort was a median of 4.7 years with 20 deaths in the ICD group and 29 deaths in the no-ICD group. The median survival in the ICD group was 8.0 years and 3.1 years in the no-ICD group. Crude analysis showed a better survival in the ICD group as compared to the no-ICD group (p = 0.016). The multivariable analysis confirmed that the ICD group had significantly less all-cause mortality compared to the no-ICD group (HR: 0.40; 95% CI: 0.19, 0.82; p = 0.013). CONCLUSION: An ICD is associated with a higher survival in ESRD patients with left ventricular dysfunction. This result merits further study in a larger cohort of patients.

Author Correction: Non-Markovianity of qubit evolution under the action of spin environment.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Non-Markovianity of qubit evolution under the action of spin environment.

The question, whether an open system dynamics is Markovian or non-Markovian can be answered by studying the direction of the information flow in the dynamics. In Markovian dynamics, information must always flow from the system to the environment. If the environment is interacting with only one of the subsystems of a bipartite system, the dynamics of the entanglement in the bipartite system can be used to identify the direction of information flow. Here we study the dynamics of a two-level system interacting with an environment, which is also a heat bath, and consists of a large number of two-level quantum systems. Our model can be seen as a close approximation to the 'spin bath' model at low temperatures. We analyze the Markovian nature of the dynamics, as we change the coupling between the system and the environment. We find the Kraus operators of the dynamics for certain classes of couplings. We show that any form of time-independent or time-polynomial coupling gives rise to non-Markovianity. Also, we witness non-Markovianity for certain parameter values of time-exponential coupling. Moreover, we study the transition from non-Markovian to Markovian dynamics as we change the value of coupling strength.

Persistent left superior vena cava: a case report and review of literature.

Persistent left superior vena cava is rare but important congenital vascular anomaly. It results when the left superior cardinal vein caudal to the innominate vein fails to regress. It is most commonly observed in isolation but can be associated with other cardiovascular abnormalities including atrial septal defect, bicuspid aortic valve, coarctation of aorta, coronary sinus ostial atresia, and cor triatriatum. The presence of PLSVC can render access to the right side of heart challenging via the left subclavian approach, which is a common site of access utilized when placing pacemakers and Swan-Ganz catheters. Incidental notation of a dilated coronary sinus on echocardiography should raise the suspicion of PLSVC. The diagnosis should be confirmed by saline contrast echocardiography.