Efficacy of Radial Endobronchial Ultrasound (R-EBUS) guided transbronchial cryobiopsy for peripheral pulmonary lesions (PPL...s): A systematic review and meta-analysis

BACKGROUND

Transbronchial lung cryobiopsy (TBLC) is frequently described for the diagnosis of diffuse parenchymal lung diseases (DPLD). A few studies have reported transbronchial cryobiopsy for the diagnosis of peripheral pulmonary lesions (PPL...s). We aimed to study the utility and safety of transbronchial cryobiopsy for the diagnosis of PPL...s.

METHODS

We performed a systematic search of the PubMed and Embase databases to extract the relevant studies. We then performed a meta-analysis to calculate the diagnostic yields of transbronchial cryobiopsy and bronchoscopic forceps biopsy.

RESULTS

Following a systematic search, we identified nine relevant studies (300 patients undergoing cryobiopsy). All used Radial Endobronchial Ultrasound (R-EBUS) for PPL localization. The pooled diagnostic yield of transbronchial cryobiopsy was 77% (95% CI, 71%...84%) (I^2=38.72%, p=0.11). The diagnostic yield of forceps biopsy was 72% (95% CI, 60%...83%) (I^2=78.56%, p<0.01). The diagnostic yield of cryobiopsy and forceps biopsy was similar (RR 1.05, 95% CI 0.96...1.15), with a 5% risk difference for diagnostic yield (95% CI, ...6% to 15%). There was significant heterogeneity (I^2=57.2%, p=0.017), and no significant publication bias. One severe bleeding and three pneumothoraxes requiring intercostal drain (ICD) placement (major complication rate 4/122, 1.8%) were reported with transbronchial cryobiopsy.

CONCLUSIONS

R-EBUS guided transbronchial cryobiopsy is a safe and efficacious modality. The diagnostic yields of TBLC and forceps biopsy are similar. More extensive multicentre randomized trials are required for the further evaluation and standardization of transbronchial cryobiopsy for PPL...s.

Effect of mindfulness on online impulse buying: Moderated mediation model of problematic internet use and emotional intelligence

Introduction

Online impulse buying behavior is an unplanned urge to buy a product or service in an online setting and it has several negative consequences for customers, such as guilt and financial distress, and e-commerce firms, such as higher returns and customer complaints. Evidently, it is important to examine the various psychological processes which may assist in a better understanding, therefore addressing the high prevalence of online impulse buying. This study builds upon self-regulation theory to explore how mindfulness influences online impulse buying, and examines problematic internet use as a mediator in the relationship between mindfulness and online impulse buying. Further, this study investigates how emotional intelligence as a moderator plays the role of a suppressant on the adverse impact of problematic Internet use which fuels online impulse buying.

Method

A total of 598 individuals working with various servicebased industries responded to the questionnaire. Multiple regression and moderated mediation analysis was used using SPSS and AMOS for analyzing the data.

Result

Problematic internet use mediates the relationship between mindfulness and online impulse buying behavior. Emotional intelligence negatively moderates the relationship between problematic internet use and online impulse buying behavior.

Discussion

This study findings outlined the inverse relationship of mindfulness & online impulse buying, along with the mediating effect of problematic internet use between mindfulness and online impulse buying. Further, this study showed how emotional intelligence played an important role as a moderator by suppressing the adverse impact of problematic Internet use and preventing online impulse buying. The study offers implications to online marketers in regulating the unplanned purchase process-while minimizing uninhibited buying behavior that leads to regret, and the subsequent intention to return products. Further, social and theoretical implications are discussed.

Clinical profile of small-cell lung cancer in North India: A 12-year analysis from a tertiary care center

Introduction

The small cell variant is a relatively uncommon but aggressive form of lung cancer. The present study aims to analyse the clinical characteristics, treatment outcomes and prognostic factors of an ambispectively enrolled large cohort of small cell lung cancer (SCLC) in the Indian population over a decade-long period.

Materials and Methods

All patients diagnosed with SCLC between 2008 and 2020 at a tertiary care lung cancer clinic were included. The clinical details, demographics, details of investigations, treatment and survival outcomes were recorded and analysed.

Results

A total of 361 patients were included. The majority were males (86.4%) with a mean (SD) age of 57.3 (12.3) years. Further, 34.9% were current smokers, with the median smoking index being 520 (interquartile range [IQR]: 260-1000). The majority had good performance status, that is, the Eastern Cooperative Oncology Group scale (ECOG) 0 or 1 (65%), and Karnofsky Performance Scale (KPS) ≥70 (85.9%). Also, 73.3% had extensive stage disease. The median time from symptom onset to definitive diagnosis was 91 days. Treatment details were available for 179 patients: chemotherapy only (n = 128), combined chemo-radiotherapy (n = 41) and radiotherapy only (n = 10). The median (IQR) progression-free survival (PFS) was 182 (94 to 306) days and the median (IQR) overall survival (OS) was 205 (94 to 429) days. On univariate analysis, factors that significantly affected survival included smoking index and performance status. However, on multivariate analysis, only the performance status significantly affected PFS, whereas none of these factors were significant for OS.

Conclusions

SCLC predominantly affects males with a heavy smoking index. The diagnosis is usually made late; survival remains poor and is predominantly affected by the performance status.

The diagnostic utility of ultrasound elastography to differentiate tuberculosis and sarcoidosis during endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA)

Introduction

Elastography is a non-invasive tool that may allow differentiation between benign and malignant lymph nodes during endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). In tuberculosis (TB) endemic areas, clinicoradiological features of mediastinal TB and sarcoidosis often overlap, rendering an accurate diagnosis challenging. There is interest in the identification of modalities to aid in this differentiation. There are currently no published data on the utility of EBUS-elastography in differentiating between TB and sarcoidosis.

Methods

Subjects undergoing EBUS-TBNA were prospectively enrolled, and elastography features were observed. Subjects with definitive diagnosis of TB or sarcoidosis were enrolled. The elastography features recorded included the three-colour classification patterns and strain ratio.

Results

We enrolled 96 subjects with a definitive diagnosis (53 with TB and 43 with sarcoidosis). Of the 27 patients in whom the lymph nodes were classified as type 1 on endobronchial ultrasound elastography colour pattern, 17 had a diagnosis of TB (62.9%), while 10 were sarcoidosis (37%). For type 2 lymph nodes, 20/45 (44.4%) were TB and 25/45 (55.6%) were sarcoidosis. Type 3 lymph nodes were TB in 16/24 (66.7%) and sarcoidosis in 8/24 (33.3%). In classifying type 1 as 'sarcoidosis' and Type 3 as 'tubercular', the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy were 48.5%, 55.6%, 66.7%, 37%, and 0.51, respectively. The strain ratio (Median [IQR]) was 1.29 (0.37-5.98) in TB and 2.10 (0.83-4.52) in sarcoidosis group (P = 0.48).

Conclusion

Ultrasound elastographic lymph node characteristics have a poor diagnostic utility to differentiate between TB and sarcoidosis during EBUS-TBNA.

Absence of atrial fibrillation in the blanking period following cryoballoon pulmonary vein isolation – does it always portend a good prognosis?

Background

Cryoballoon (CB) pulmonary vein isolation (PVI) is an accepted method for ablation in patients with paroxysmal and persistent atrial fibrillation (PAF, PeAF). Freedom from AF in the blanking period (BP), conventionally defined as the first 3-months post-PVI, has been associated with the best long-term outcomes. However, the influence of antiarrhythmic drugs (AADs) during the BP on long-term outcomes is not well understood.

Objective

To compare long-term outcomes between patients who were and were not on an AAD prior to ablation and remained free from AF during the 3-month BP post CB PVI.

Methods

We enrolled consecutive AF patients undergoing CB PVI; all pts had an implantable loop recorder (ILR). No patient had any AF in the first 90 days post CB PVI. We divided the patients into three groups: (1) never had exposure to an AAD; (2) were intolerant to/failed AAD and thus were not taking an AAD at time of ablation; and (3) were on AAD at time of ablation. In the latter group, every effort was made to stop the AAD before the end of the BP.

Results

The cohort included 96 pts (66±10 years; 60 [63%] male; 55 [57%] PAF; CHA2DS2-VASc 2.5±1.4). There were 23 (24%) patients in group 1, 13 (14%) patients in group 2, and 60 (63%) pts in group 3. Patients in group 3 were more likely to have PeAF; AADs were stopped at a median of 36 days IQR (27, 91) in this group. Patients were followed for 1-year during which time 28 (29%) patients had recurrent AF (despite having no AF during the BP). The best outcome was seen in patients who never used an AAD; the worst outcome was seen in patients who were on an AAD at time of ablation (Figure 1).

Conclusion

Our data show that absence of AF during a 3-month post CB PVI BP alone does not guarantee good-long term outcome, unless the patient was never treated with an AAD. In contrast, in patients ablated while taking an AAD, recurrent AF was observed in 37% even though they were completely AF-free during the BP.

Funding Acknowledgement

Type of funding sources: None.

Recurrence of atrial fibrillation following pulmonary vein isolation: impact of body mass index on one- and three-year outcomes

Background

Cryoballoon (CB) pulmonary vein isolation (PVI) is an accepted method for ablation in patients with paroxysmal and persistent atrial fibrillation (PAF, PeAF). However, there are a paucity of data about the impact of body mass index (BMI) on one-year and longer-term outcomes following ablation.

Objective

To objectively understand the impact of BMI on outcomes following CB PVI.

Methods

We enrolled consecutive AF patients undergoing CB PVI; all patients had an implantable loop recorder (ILR), which transmitted data wirelessly daily. We assessed AF recurrences after excluding an initial 3-month post-ablation blanking period.

Results

The cohort included 222 pts (66±9 years; 143 [64%] male; 120 [54%] PAF; CHA2DS2-VASc 2.6±1.6). The mean BMI was 30±5. Patients were followed for 763±347 days, during which time 50% and 68% had recurrent AF 1- and 3-years post ablation. We divided the cohort based on the mean BMI into 2 groups: BMI &lt;30 and BMI &gt;30. Heavier patients were younger and more likely to have PeAF. Over 1-year of follow-up, patients with a BMI &lt;30 had similar likelihood of being free of AF to patients with a BMI &gt;30 (46% vs, 56%, p=0.0.097, Figure 1, left). However, as patients were followed for 3-years, freedom from AF was significantly higher in patients with a BMI &lt;30 (59% vs. 81% in BMI &gt;30, p=0.002, Figure 1, right).

Conclusions

Our data show that although patients had similar outcomes 1-year post-ablation, during longer-term follow-up patients with a BMI &gt;30 had a much worse outcome. Our study uniquely offers objective (using an ILR) assessment of the impact of BMI on long-term outcomes following CB PVI (homogenous ablation strategy). These data highlight the need to identify strategies to improve outcomes in obese patients.

Funding Acknowledgement

Type of funding sources: None.

The Effectiveness of SARS-CoV-2 Vaccination in Preventing Severe Illness and Death - Real-world Data from a Cohort of Patients Hospitalized with COVID-19

Background

While long-term studies on the correlates of protection, vaccine effectiveness, and enhanced surveillance are awaited for SARS-CoV-2 vaccine, studies on breakthrough infections help understand the nature and course of this illness among vaccinated individuals and guide in public health preparedness. This study aims to compare the differences in the hospitalization outcomes SARS-CoV-2 infection of fully vaccinated individuals with with those of unvaccinated and partially vaccinated individuals.

Materials and Methods

Single institution observational cohort study. This study compared the differences in clinical, biochemical parameters and the hospitalization outcomes of 53 fully vaccinated individuals with those of unvaccinated (1464) and partially vaccinated (231) individuals, among a cohort of 2,080 individuals hospitalized with SARS-CoV-2 infection. Descriptive statistics and propensity-score weighted multivariate logistic regression analysis adjusting for clinical and laboratory parameters were used to compare the differences and to identify factors associated with outcomes.

Results

Completing the course of vaccination protected individuals from developing severe COVID-19 as evidenced by lower proportions of those with hypoxia, abnormal levels of inflammatory markers, requiring ventilatory support, and death compared to unvaccinated and partially vaccinated individuals. There were no differences in these outcomes among patients who received either vaccine type approved in India.

Conclusions

Efforts should be made to improve the vaccination rates as a timely measure to prepare for the upcoming waves of this highly transmissible pandemic. Vaccination rates of the communities may also guide in the planning of the health needs and appropriate use of medical resources.

Dexmedetomidine Versus Midazolam for Sedation During Medical Thoracoscopy: A Pilot Randomized-Controlled Trial (RCT)

BACKGROUND

Studies comparing the utility of dexmedetomidine with other drugs for sedation during medical thoracoscopy are lacking. In this pilot study, we compared dexmedetomidine with midazolam for sedation in thoracoscopy.

METHODS

Consecutive subjects were randomized to receive either dexmedetomidine (n=30) (group D) or midazolam (n=30) (group M). All received fentanyl for procedural analgesia. The primary endpoint was pulmonologist-rated overall procedure satisfaction on the visual analog scale (satisfaction VAS). Key secondary outcomes were pulmonologist-rated cough on VAS (cough VAS), patient-rated faces pain scale scores, change in hemodynamic variables, total additional fentanyl dose, and adverse events during procedure.

RESULTS

The satisfaction VAS score (mean±SD) was significantly greater in group D versus group M (7.5±1.4 and 6.5±1.1, respectively) ( P =0.003). The cough VAS scores (mean±SD) were 2.1±1.5 (group D) and 3.1±1.3 (group M) ( P =0.014). The scores (mean±SD) for patient-rated faces pain scale were 2.9±1.8 and 4.2±2.3 ( P =0.019) in group D and group M, respectively. The additional dose of fentanyl administered in group M was significantly greater than in group D ( P =0.001). The responses at the local anesthesia infiltration, skin incision, thoracoscope insertion, and biopsy between both groups were similar. The hemodynamic parameters were comparable in both groups. Also, more patients were willing for repeat thoracoscopy if needed; in the dexmedetomidine group.

CONCLUSION

The findings of this pilot RCT indicate that dexmedetomidine may be more efficacious than midazolam for sedation in patients undergoing medical thoracoscopy. These observations need to be confirmed in an adequately powered RCT.

A Delphi consensus statement for the management of post-COVID interstitial lung disease

INTRODUCTION

As millions of people worldwide recover from COVID-19, a substantial proportion continue to have persistent symptoms, pulmonary function abnormalities, and radiological findings suggestive of post-COVID interstitial lung disease (ILD). To date, there is limited scientific evidence on the management of post-COVID ILD, necessitating a consensus-based approach.

AREAS COVERED

A panel of experts in pulmonology and thoracic radiology was constituted. Key questions regarding the management of post-COVID ILD were identified. A search was performed on PubMed and EMBASE and updated till 1 March 2022. The relevant literature regarding the epidemiology, pathophysiology, diagnosis and treatment of post-COVID ILD was summarized. Subsequently, suggestions regarding the management of these patients were framed, and a consensus was obtained using the Delphi approach. Those suggestions which were approved by over 80% of the panelists were accepted. The final document was approved by all panel members.

EXPERT OPINION

Dedicated facilities should be established for the care of patients with post-COVID ILD. Symptom screening, pulmonary function testing, and thoracic imaging have a role in the diagnosis. The pharmacologic and non-pharmacologic options for the management of post-COVID ILD are discussed. Further research into the pathophysiology and management of post-COVID ILD will improve our understanding of this condition.

Solid Self-Nano Emulsifying Nanoplatform Loaded with Tamoxifen and Resveratrol for Treatment of Breast Cancer

The solid self-nanoemulsifying drug delivery system (s-SNEDDS) is a growing platform for the delivery of drugs via oral route. In the present work, tamoxifen (TAM) was loaded in SNEDDS with resveratrol (RES), which is a potent chemotherapeutic, antioxidant, anti-inflammatory and P-gp inhibitor for enhancing bioavailability and to obtain synergistic anti-cancer effect against breast cancer. SNEDDS were developed using capmul MCM as oil, Tween 80 as surfactant and transcutol-HP as co-surfactant and optimized by central composite rotatable design. Neusilin US2 concentration was optimized for adsorption of liquid SNEDDS to prepare s-SNEDDS. The developed formulation was characterized and investigated for various in vitro and cell line comparative studies. Optimized TAM-RES-s-SNEDDS showed spherical droplets of a size less than 200 nm. In all in vitro studies, TAM-RES-s-SNEDDS showed significantly improved (p ˂ 0.05) release and permeation across the dialysis membrane and intestinal lumen. Moreover, TAM-RES-s-SNEDDS possessed significantly greater therapeutic efficacy (p < 0.05) and better internalization on the MCF-7 cell line as compared to the conventional formulation. Additionally, oral bioavailability of TAM from SNEDDS was 1.63 folds significantly higher (p < 0.05) than that of combination suspension and 4.16 folds significantly higher (p < 0.05) than TAM suspension. Thus, findings suggest that TAM- RES-s-SNEDDS can be the future delivery system that potentially delivers both drugs to cancer cells for better treatment.

Indian Guidelines on Nebulization Therapy

Inhalational therapy, today, happens to be the mainstay of treatment in obstructive airway diseases (OADs), such as asthma, chronic obstructive pulmonary disease (COPD), and is also in the present, used in a variety of other pulmonary and even non-pulmonary disorders. Hand-held inhalation devices may often be difficult to use, particularly for children, elderly, debilitated or distressed patients. Nebulization therapy emerges as a good option in these cases besides being useful in the home care, emergency room and critical care settings. With so many advancements taking place in nebulizer technology; availability of a plethora of drug formulations for its use, and the widening scope of this therapy; medical practitioners, respiratory therapists, and other health care personnel face the challenge of choosing appropriate inhalation devices and drug formulations, besides their rational application and use in different clinical situations. Adequate maintenance of nebulizer equipment including their disinfection and storage are the other relevant issues requiring guidance. Injudicious and improper use of nebulizers and their poor maintenance can sometimes lead to serious health hazards, nosocomial infections, transmission of infection, and other adverse outcomes. Thus, it is imperative to have a proper national guideline on nebulization practices to bridge the knowledge gaps amongst various health care personnel involved in this practice. It will also serve as an educational and scientific resource for healthcare professionals, as well as promote future research by identifying neglected and ignored areas in this field. Such comprehensive guidelines on this subject have not been available in the country and the only available proper international guidelines were released in 1997 which have not been updated for a noticeably long period of over two decades, though many changes and advancements have taken place in this technology in the recent past. Much of nebulization practices in the present may not be evidence-based and even some of these, the way they are currently used, may be ineffective or even harmful. Recognizing the knowledge deficit and paucity of guidelines on the usage of nebulizers in various settings such as inpatient, out-patient, emergency room, critical care, and domiciliary use in India in a wide variety of indications to standardize nebulization practices and to address many other related issues; National College of Chest Physicians (India), commissioned a National task force consisting of eminent experts in the field of Pulmonary Medicine from different backgrounds and different parts of the country to review the available evidence from the medical literature on the scientific principles and clinical practices of nebulization therapy and to formulate evidence-based guidelines on it. The guideline is based on all possible literature that could be explored with the best available evidence and incorporating expert opinions. To support the guideline with high-quality evidence, a systematic search of the electronic databases was performed to identify the relevant studies, position papers, consensus reports, and recommendations published. Rating of the level of the quality of evidence and the strength of recommendation was done using the GRADE system. Six topics were identified, each given to one group of experts comprising of advisors, chairpersons, convenor and members, and such six groups (A-F) were formed and the consensus recommendations of each group was included as a section in the guidelines (Sections I to VI). The topics included were: A. Introduction, basic principles and technical aspects of nebulization, types of equipment, their choice, use, and maintenance B. Nebulization therapy in obstructive airway diseases C. Nebulization therapy in the intensive care unit D. Use of various drugs (other than bronchodilators and inhaled corticosteroids) by nebulized route and miscellaneous uses of nebulization therapy E. Domiciliary/Home/Maintenance nebulization therapy; public & health care workers education, and F. Nebulization therapy in COVID-19 pandemic and in patients of other contagious viral respiratory infections (included later considering the crisis created due to COVID-19 pandemic). Various issues in different sections have been discussed in the form of questions, followed by point-wise evidence statements based on the existing knowledge, and recommendations have been formulated.

Efficacy of Intrabronchial Voriconazole Instillation for Inoperable Pulmonary Aspergilloma: A Pilot Randomized Controlled Trial

<b><i>Background:</i></b> Endobronchial administration of voriconazole is a potential therapeutic option for inoperable aspergilloma. <b><i>Objective:</i></b> This study aimed to assess the efficacy of endobronchial instillation of voriconazole for inoperable pulmonary aspergilloma. <b><i>Method:</i></b> Patients with mild to moderate hemoptysis, due to inoperable aspergilloma, were randomized to receive either medical therapy (MT) alone or bronchoscopic instillation of voriconazole with MT and followed up till 3 months. The primary objective of this study was to compare the percentage of patients achieving reduction in the severity of hemoptysis assessed on visual analogue scale (VAS) in intervention and control arm at 3 months. <b><i>Results:</i></b> This study included 60 patients (female = 47) with mean (SD) age of 40.6 (13.2) years who were randomized to receive either bronchoscopic instillation of voriconazole (<i>n</i> = 30) or MT alone (<i>n</i> = 30). At 3-month follow-up, the primary objective was achieved in 26/30 (86.7%) patients in intervention group as compared to 11/30 (36.7%) in the control group (<i>p</i> value &#x3c;0.0001). The VAS score at 3 months was significantly lower in voriconazole group 13.9 (9.3) mm as compared to MT alone group 22.3 (11.5) mm, <i>p</i> value of 0.003. Bronchoscopic instillation of voriconazole was also associated with reduction in cough severity and size of the aspergilloma; however, there was no benefit of this therapy in terms of requirement of hospitalization and BAE. <b><i>Conclusions:</i></b> Our study shows that for nonoperable aspergilloma, bronchoscopic instillation of voriconazole is associated with reduction in the severity of hemoptysis. This therapy should be evaluated in large multi-center trials.

Clinical profile and in-hospital outcomes of COVID-19 among adolescents at a tertiary care hospital in India

Introduction

We aimed to describe the clinical profile and risk factors for severe disease in adolescents hospitalised with coronavirus disease 2019 (COVID-19).

Methods

A retrospective analysis of an admitted cohort of COVID-19 patients was performed at a tertiary hospital in North India. Adolescents aged 12-18 years who were hospitalised during the first wave (March-December, 2020) and the second wave (March-June, 2021) were included. Data on the demographic details, clinical presentation, laboratory parameters, disease severity at admission, treatments received, and in-hospital outcomes were retrieved.

Results

The study included 197 adolescents with a median [inter-quartile range (IQR)] age of 15 (13-17) years, of whom 117 (59.4%) were male. Among these, 170 (86.3%) were admitted during the first wave. Underlying co-morbidities were present in nine (4.6%) patients. A total of 60 (30.9%) patients were asymptomatic. In the severity grading, 148 (84.6%) had mild, 16 (9.1%) had moderate, and 11 (6.3%) had severe disease. Fever (14.9%) and cough (14.9%) were the most commonly encountered symptoms. The median (IQR) duration of hospital stay was 10 (8-13) days, and six (3.1%) patients died in the hospital.

Conclusion

Adolescents admitted with COVID-19 had predominantly asymptomatic or mild disease, and the mortality rate was 3.1%.

Covid-19 presenting as isolated severe thrombocytopenia in an HIV-lymphoma survivor

Coronavirus disease has myriad manifestations and can present with predominantly extrapulmonary manifestations. We describe a 50-year-old man, a person living with HIV (PLHA), a non-Hodgkin lymphoma survivor, who presented with isolated severe thrombocytopenia. He was found to have immune-mediated thrombocytopenia, and showed excellent response to intravenous immunoglobulins.

Tuberculosis endemicity and BCG vaccination: Protection against COVID-19

The coronavirus disease 2019 (COVID-19) has affected different countries in a differential manner. The host susceptibility and host factors are important parameters for this variability. This study aimed to assess the effect of tuberculosis (TB) endemicity and Bacille Calmette-Guerin (BCG) coverage on COVID-19. Available data regarding TB incidence, BCG coverage (as per the World Health Organization), and COVID-19 incidence of 168 countries as of 19th September 2021was collected. Countries were divided into four cohorts based upon annual TB incidence and BCG coverage and COVID-19 incidence and case fatality rates were compared using the Kruskal-Wallis test. Countries with low TB incidence and low BCG coverage had the highest COVID-19 incidence per lac population. However, no significant difference was seen in COVID-19 cases fatality rate. Higher TB incidence and BCG coverage were associated with lesser incidence of COVID-19. This result paves the way for research into pathogenesis and host immune response in COVID-19.

Superconducting-qubit readout via low-backaction electro-optic transduction

Entangling microwave-frequency superconducting quantum processors through optical light at ambient temperature would enable means of secure communication and distributed quantum information processing¹. However, transducing quantum signals between these disparate regimes of the electro-magnetic spectrum remains an outstanding goal^2-9, and interfacing superconducting qubits, which are constrained to operate at millikelvin temperatures, with electro-optic transducers presents considerable challenges owing to the deleterious effects of optical photons on superconductors^9,10. Moreover, many remote entanglement protocols^11-14 require multiple qubit gates both preceding and following the upconversion of the quantum state, and thus an ideal transducer should impart minimal backaction¹⁵ on the qubit. Here we demonstrate readout of a superconducting transmon qubit through a low-backaction electro-optomechanical transducer. The modular nature of the transducer and circuit quantum electrodynamics system used in this work enable complete isolation of the qubit from optical photons, and the backaction on the qubit from the transducer is less than that imparted by thermal radiation from the environment. Moderate improvements in the transducer bandwidth and the added noise will enable us to leverage the full suite of tools available in circuit quantum electrodynamics to demonstrate transduction of non-classical signals from a superconducting qubit to the optical domain.

The impact of atrial fibrillation burden early post cryoballoon pulmonary vein isolation on long-term freedom from recurrent atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Background

Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation. A three-month blanking period (BP) is commonly used in clinical trials and practice. Early recurrence of AF portends worse ablation long-term outcome; however, the utility of using AF burden (AFB) early post cryoballoon (CB) PVI to predict long-term outcome is unknown.

Purpose

To determine, using ECG data acquired by an implantable loop recorder (ILR), the relationship between post-ablation AFB and long-term freedom from AF.

Methods

We enrolled consecutive patients with AF who had CB PVI and an ILR. We determined the monthly AFB for the first 3 months post CB PVI and assessed the relationship between AFB and 1-year freedom from AF. We defined 4 distinct AFB groups: (1) 0%, (2) &gt; 0-0.1%, (3) &gt; 0.1-0.5%, and (4) &gt; 0.5%.

Results

There were 210 patients (66 ± 9 years; 138 [66%] male; 116 [55%] paroxysmal AF; CHA2DS2-VASc 2.5 ± 1.6). Following a 3-month BP, 101 (48%) patients had a recurrence of AF at 160 ± 86 days post-ablation. An AFB of &gt; 0% over the first 3 months predicted AF recurrence (p &lt; 0.0001, Figure 1). Patients with &gt; 0.5% AF burden after 1st month and any AF after 2nd month post CB PVI have a very high long-term AF recurrence rate (Figure 2).

Conclusion

The best long term outcome post CB PVI is seen in pts who have no AF in the first 3 months post ablation. An AFB &gt;0.5% after the first month and any AF after the second month portend ablation failure. These data define a clinical utility of using AFB to risk stratify patients post CB PVI.

Yearly incidence and pattern of very late recurrence of atrial fibrillation as detected by continuous electrocardiographic monitoring using an implantable loop recorder

Funding Acknowledgements

Type of funding sources: None.

Background

A very late recurrence (VLR) of atrial fibrillation (AF) is considered present when patients have their first recurrence of AF &gt; 12 months post-ablation. Little is known about the yearly rates and patterns of VLR AF recurrence.

Objective

To assess the yearly incidence and pattern of VLR in pts with AF who underwent cryoballoon (CB) pulmonary vein isolation (PVI).

Methods

We prospectively enrolled consecutive patients with AF who underwent CB PVI and had an implantable loop recorder (ILR) inserted up to 3 months post-ablation. Patients were followed for recurrent AF (excluding a 3-month post-ablation blanking period).

Results

Our cohort included 222 patients (66 ± 9 years; 143 [64%] male; 120 [54%] paroxysmal AF; CHA2DS2-VASc 2.6 ± 1.6). At 1-year, 111 (50%) patients remained free of AF. Two-year follow-up was available in 95 of these patients; 62 (65%) remained in sinus. Three-year follow-up was available in 42 of these patients; 36 (86%) remained in sinus (Figure). Of the 39 patients who developed AF after initially being free of AF for at least 1-year post ablation, 24 (62%) patients had either a frequent or persistent pattern of AF.

Conclusions

Our data show that the greatest likelihood of failure following a CB PVI occurs in the first year of ablation. The rate of failure becomes lower year by year. These data suggest that long term outcome may be driven more by the initial ablation as opposed to progressive evolution of the patient’s substrate