Computed tomography predictors of increased transvenous lead extraction difficulty.

BACKGROUND: The ability of computed tomography (CT) characteristics to predict the difficulty of transvenous lead extraction (TLE) is an evolving subject. OBJECTIVE: To identify CT characteristics associated with increased TLE difficulty. METHODS: All consecutive patients undergoing TLE at the University of California San Diego from January 2018 to February 2022 were analyzed, utilizing the UC San Diego Lead Extraction Registry. Patients underwent cardiac-gated chest CT scans with intravenous contrast; all scans were reviewed by a single radiologist. Lead extraction was performed per standard institutional protocol with the initial use of a laser sheath and crossover to a mechanical sheath as needed. Multivariable linear and logistic regression analyses were performed to identify predictors of individual lead-removal fluoroscopy time and mechanical sheath use, as markers of extraction difficulty. RESULTS: A total of 343 patients were analyzed. The mean age of the study population was 63.8 ± 15.4 years; 71% were male. The mean lead dwell-in duration was 8.6 ± 5.7 years. In multivariable linear regression analysis, venous occlusion detected on CT was independently associated with higher individual lead-removal fluoroscopy time (p = 0.004), when adjusting for clinical characteristics such as lead dwell time. In multivariable logistic regression analysis, calcification and venous occlusion were independently associated with a higher need for mechanical sheath use during TLE (odds ratio:5.08, p < 0.001, 95% CI: 2.54-10.46) and (odds ratio:3.72, p < 0.001, 95% CI: 1.89-7.35), respectively. CONCLUSION: In patients undergoing TLE, venous occlusion identified by chest CT is associated with increased fluoroscopy time. Patients with lead-associated calcification or venous occlusion detected by chest CT are each five and three times more likely to require crossover from laser to a mechanical sheath.

Inflammatory biomarkers as predictors of systemic vs isolated pocket infection in patients undergoing transvenous lead extraction.

Background: Cardiovascular implantable electronic device (CIED) infections are a common indication for device extraction. Early diagnosis and complete system removal are crucial to reduce morbidity and mortality. The lack of clear infectious symptoms makes the diagnosis of pocket infections challenging and may delay referral for extraction. Objective: We aimed to determine if inflammatory biomarkers can help diagnose CIED isolated pocket infection. Methods: We performed a retrospective analysis of all patients undergoing transvenous lead extraction for CIED infection at the University of California San Diego from 2012 to 2022 (N = 156). Patients were classified as systemic infection (n = 88) or isolated pocket infection (n = 68). Prospectively collected preoperative procalcitonin (PCT), C-reactive protein, and white blood cell count were compared between groups. Results: Pairwise comparisons revealed that the systemic infection group had a higher PCT than the control group (P < .001) and the pocket infection group (P = .009). However, there was no significant difference in PCT value between control subjects and isolated pocket infection subjects. Higher white blood cell count was only associated with systemic infection when compared with our control group (P = .018). Conclusion: In patients diagnosed with CIED infections requiring extraction, inflammatory biomarkers were not elevated in isolated pocket infection. Inflammatory markers are not predictive of the diagnosis of pocket infections, which ultimately requires a high level of clinical suspicion.

Open Chest Approach Lead Extraction in a Patient with a Large Vegetation: The Importance of Multidisciplinary Approach, Advanced Imaging, and Procedural Planning.

We present a complex case of cardiac implantable electronic device infection and extraction in the setting of bacteremia, large lead vegetation, and patent foramen ovale. Following a comprehensive preprocedural workup including transesophageal echocardiogram and computed tomography lead extraction protocol, in addition to the involvement of multiple subspecialties, an open chest approach to extraction was deemed a safer option for eradication of the patient's infection. Despite percutaneous techniques having evolved as the preferred extraction method during the last few decades, this case demonstrates the importance of a thorough evaluation at an experienced center to determine the need for open chest extraction.

Clinician Prediction of Survival vs Calculated Prediction Scores in Patients Requiring Extracorporeal Membrane Oxygenation.

BACKGROUND: Determining appropriate extracorporeal membrane oxygenation (ECMO) candidacy ensures appropriate utilization of this costly resource. The current ECMO survival prediction scores do not consider clinician assessment of patient viability. This study compared clinician prediction of survival to hospital discharge versus prediction scores. OBJECTIVES: The aim of this study was to compare clinician prediction of patients' survival to hospital discharge versus prognostic prediction scores (Respiratory ECMO Survival Prediction [RESP] or Survival After Veno-Arterial ECMO [SAVE] score) to actual survival. METHODS: This was an observational descriptive study from January 2020 to November 2021 conducted with interviews of nurses, perfusionists, and physicians who were involved during the initiation of ECMO within the first 24 hours of cannulation. Data were retrieved from the medical record to determine prediction scores and survival outcomes at hospital discharge. Accuracy of clinician prediction of survival was compared to the RESP or SAVE prediction scores and actual survival to hospital discharge. RESULTS: Accurate prediction of survival to hospital discharge for veno-venous ECMO by nurses was 47%, 64% by perfusionists, 45% by physicians, and 45% by the RESP score. Accurate predictions of patients on veno-arterial ECMO were correct in 54% of nurses, 77% of physicians, and 14% by the SAVE score. Physicians were more accurate than the SAVE score, P = .021, and perfusionists were significantly more accurate than the RESP score, P = .044. There was no relationship between ECMO specialists' years of experience and accuracy of predications. CONCLUSION: Extracorporeal membrane oxygenation clinicians may have better predictions of survival to hospital discharge than the prediction scores. Further research is needed to develop accurate prediction tools to help determine ECMO eligibility.

Using HCV-viremic organs for lung transplantation does not confer higher rejection rates compared to HCV-negative organs.

BACKGROUND: National data demonstrate that hepatitis C virus (HCV)-infected organ donors are increasingly being used in the US, including for lung transplantation. We aimed to assess whether there were any differences in the acute or chronic rejection rates at 1 year following lung transplantation from HCV-viremic versus uninfected donors. METHODS: We retrospectively reviewed all lung transplant recipients at our institution from April 1, 2017 to October 1, 2020 and then assessed various outcomes between those who received a transplant from HCV-viremic donors versus HCV-negative donors. Primary outcome was to determine if there was a higher incidence of acute and/or chronic allograft rejection when using HCV NAT+ lung donation. We carried out univariate and multivariate analyses. RESULTS: We transplanted 135 patients during the study period, including 18 from HCV-viremic donors. Standard induction therapy with basiliximab and maintenance triple drug immunosuppression was utilized per UC San Diego protocol. All 17 patients receiving HCV-viremic organs developed acute HCV infection and were treated in the postoperative period with 12 weeks of direct acting antivirals (DAA). HCV genotypes included 1, 2, and 3. DAA used included glecaprevir/pibrentasvir (12), sofosbuvir/velpatasvir (1), and ledipasvir/sofosbuvir (2) with drug choice determined by patient's medical insurance coverage. Sustained virological response at 12 weeks after end of DAA therapy (SVR12), indicative of a cure, was achieved in all (100%) recipients. No recipient had a serious adverse event related to HCV infection. The lung transplant recipient (LTR) HCV-viremic donors had lower rates of clinically significant rejection (5.9% vs. 11% LTR HCV-nonviremic donors), and no chronic lung allograft dysfunction at 1 year (vs. 5.9% LTR HCV-nonviremic donors). One-year survival was 100% in the LTR HCV-viremic donors compared to 95.8% in the LTR HCV-nonviremic donors. CONCLUSIONS: We demonstrate the feasibility and success of using HCV NAT + donors with excellent results and without a higher incidence of rejection. Longer term follow-up and a larger sample size are needed to allow this to be a more widely accepted practice for lung transplant programs and payors.

Using Cardiohelp, Quadrox, and Nautilus Extracorporeal Membrane Oxygenators as Vascular Access for Hemodialysis, Continuous Renal Replacement Therapy, and Plasmapheresis: A Brief Technical Report.

The use of intermittent hemodialysis (iHD), and continuous renal replacement therapy (CRRT), along with extracorporeal membrane oxygenation (ECMO) in patients with acute kidney injury (AKI) and end-stage renal disease (ESRD) is very common. In this technical report, we describe the methods to perform these dialytic therapies safely and effectively using the ECMO circuit in lieu of a separate dialysis catheter. Specifically, we describe in detail how to connect these kidney replacement therapy modalities to a Quadrox, Nautilus, and Cardiohelp HLS (combined oxygenator and pump) oxygenator. The dialysis (iHD or CRRT) inlet is attached to the post-oxygenators Luer-Lock, whereas the return is attached to the pre-oxygenator Luer-Lock, both with a dual lumen pigtail. We also discuss the technical aspects of performing plasmapheresis in conjunction with ECMO and iHD or CRRT. Finally, we highlight the fact that the reported technique does not require modifying the ECMO cannulas/tubing which helps maximize safety.

Very Low Driving-Pressure Ventilation in Patients With COVID-19 Acute Respiratory Distress Syndrome on Extracorporeal Membrane Oxygenation: A Physiologic Study.

OBJECTIVES: To determine in patients with acute respiratory distress syndrome (ARDS) on venovenous extracorporeal membrane oxygenation (VV ECMO) whether reducing driving pressure (ΔP) would decrease plasma biomarkers of inflammation and lung injury (interleukin-6 [IL-6], IL-8, and the soluble receptor for advanced glycation end-products sRAGE). DESIGN: A single-center prospective physiologic study. SETTING: At a single university medical center. PARTICIPANTS: Adult patients with severe COVID-19 ARDS on VV ECMO. INTERVENTIONS: Participants on VV ECMO had the following biomarkers measured: (1) pre-ECMO with low-tidal-volume ventilation (LTVV), (2) post-ECMO with LTVV, (3) during low-driving-pressure ventilation (LDPV), (4) after 2 hours of very low driving-pressure ventilation (V-LDPV, main intervention ΔP = 1 cmH2O), and (5) 2 hours after returning to LDPV. MAIN MEASUREMENTS AND RESULTS: Twenty-six participants were enrolled; 21 underwent V-LDPV. There was no significant change in IL-6, IL-8, and sRAGE from LDPV to V-LDPV and from V-LDPV to LDPV. Only participants (9 of 21) with nonspontaneous breaths had significant change (p < 0.001) in their tidal volumes (Vt) (mean ± SD), 1.9 ± 0.5, 0.1 ± 0.2, and 2.0 ± 0.7 mL/kg predicted body weight (PBW). Participants with spontaneous breathing, Vt were unchanged-4.5 ± 3.1, 4.7 ± 3.1, and 5.6 ± 2.9 mL/kg PBW (p = 0.481 and p = 0.065, respectively). There was no relationship found when accounting for Vt changes and biomarkers. CONCLUSIONS: Biomarkers did not significantly change with decreased ΔPs or Vt changes during the first 24 hours post-ECMO. Despite deep sedation, reductions in Vt during V-LDPV were not reliably achieved due to spontaneous breaths. Thus, patients on VV ECMO for ARDS may have higher Vt (ie, transpulmonary pressure) than desired despite low ΔPs or Vt.

Implantable loop recorder as a strategy following cardiovascular implantable electronic device extraction without reimplantation.

BACKGROUND: Limited data exists for outcomes in patients undergoing cardiovascular implantable electronic device (CIED) transvenous lead extraction (TLE) without clear indications for device reimplantation. The implantable loop recorder (ILR) may be an effective strategy for continuous monitoring in select individuals. OBJECTIVE: This retrospective analysis aims to investigate patients who have undergone ILR implant following TLE without CIED reimplantation. METHODS: Clinical data from consecutive patients who have undergone TLE with ILR implant and without CIED reimplantation from October 2016 to May 2020 at a single center were collected. RESULTS: Among 380 patients undergoing TLE, 28 (7.7%) underwent ILR placement without CIED reimplantation. TLE indications were systemic infection (n = 13, 46.4%), pain at the site (n = 8, 28.6%), device/lead malfunction (n = 4, 14.2%), and other. Devices extracted included: dual-chamber and single-chamber pacemaker (n = 14, 50%; n = 4, 14.2%), dual-chamber implantable cardiac defibrillator (n = 10; 35.7%), and cardiac-resynchronization therapy with defibrillator (n = 1, 3.5%). Reasons for no reimplantation included no longer meeting CIED criteria (n = 14, 50%), patient preference (n = 9, 32.1%), and no clear or inappropriate indication for initial CIED implantation (n = 5, 18%). During an average of 12.3 ± 13.1 months of follow-up, there were no lethal arrhythmias, and four (13.3%) patients underwent permanent pacemaker reimplantation due to symptomatic sinus bradycardia and atrioventricular block with syncope as discovered on ILR. Three patients died due to unknown causes (n = 1), noncardiac (n = 1), and acute coronary syndrome (n = 1). CONCLUSIONS: In patients undergoing TLE without reimplantation, an ILR may be an effective monitoring strategy in patients at low risk for cardiac arrhythmia.

Transvenous laser lead extraction in patients with congenital complete heart block.

BACKGROUND: Data on lead management in patients with congenital complete heart block (CCHB) with cardiac implantable electronic devices are lacking. OBJECTIVE: The purpose of this study was to describe the natural history and outcomes in patients with CCHB with cardiac implantable electronic devices undergoing transvenous lead extraction (TLE). METHODS: Data on all attempted TLE procedures in patients with CCHB at 2 institutions between 2011 and 2021 were collected from a retrospective registry. RESULTS: Overall, 16 patients (mean age at transvenous device implant 13.8 ± 4.7 years) were included. Before TLE, patients underwent an average of 2.25 ± 1.3 generator changes, 3 (19%) underwent cardiac resynchronization therapy upgrade, and 7 (44%) underwent a lead revision with subsequently abandoned leads. Mean patient age at TLE was 34.4 ± 9.4 years with a mean duration of lead implant of 19.2 ± 6.9 years. Lead malfunction (n = 11 [69%]) and infection (n = 5 [31%]) were the most common indications for TLE. A total of 38 leads were removed, with complete procedural success achieved in 14 of 16 (87.5%). Two (12.5%) major complications occurred, including right ventricular laceration and superior vena cava tear requiring sternotomies. All patients survived at 1-year follow-up. CONCLUSION: Patients with CCHB represent a unique cohort highlighted by several generator changes, lead revisions, and abandoned leads at a young age, along with a long duration of lead dwelling time and a high prevalence of lead malfunction requiring TLE. There may be a high risk of major complications during TLE, suggesting TLE should be performed only in experienced centers. Larger studies are needed to confirm these findings.

The Southern California Extracorporeal Membrane Oxygenation Consortium During the Coronavirus Disease 2019 Pandemic.

In March 2020, at the onset of the coronavirus disease 2019 (COVID-19) pandemic in the United States, the Southern California Extracorporeal Membrane Oxygenation (ECMO) Consortium was formed. The consortium included physicians and coordinators from the 4 ECMO centers in San Diego County. Guidelines were created to ensure that ECMO was delivered equitably and in a resource effective manner across the county during the pandemic. A biomedical ethicist reviewed the guidelines to ensure ECMO use would provide maximal community benefit of this limited resource. The San Diego County Health and Human Services Agency further incorporated the guidelines into its plans for the allocation of scarce resources. The consortium held weekly video conferences to review countywide ECMO capacity (including census and staffing), share data, and discuss clinical practices and difficult cases. Equipment exchanges between ECMO centers maximized regional capacity. From March 1 to November 30, 2020, consortium participants placed 97 patients on ECMO. No eligible patients were denied ECMO due to lack of resources or capacity. The Southern California ECMO Consortium may serve as a model for other communities seeking to optimize ECMO resources during the current COVID-19 or future pandemics.

Implementation and Outcomes of a Mobile Extracorporeal Membrane Oxygenation Program in the United States During the Coronavirus Disease 2019 Pandemic.

The coronavirus disease 2019 (COVID-19) pandemic began in the United States around March 2020. Because of limited access to extracorporeal membrane oxygenation (ECMO) in the authors' region, a mobile ECMO team was implemented by April 2020 to serve patients with COVID-19. Several logistical and operational needs were assessed and addressed to ensure a successful program, including credentialing, equipment management, and transportation. A multidisciplinary team was included in the planning, decision-making, and implementation of the mobile ECMO. From April 2020 to January 2021, mobile ECMO was provided to 22 patients in 13 facilities across four southern California counties. The survival to hospital discharge of patients with COVID-19 who received mobile ECMO was 52.4% (11 of 21) compared with 45.2% (14 of 31) for similar patients cannulated in-house. No significant patient or transportation complications occurred during mobile ECMO. Neither the ECMO nor transport teams experianced unprotected exposures to or infections with severe acute respiratory syndrome coronavirus 2. Herein, the implementation of the mobile ECMO team is reviewed, and patient characteristics and outcomes are described.