Cardiac Implantable Electronic Device Procedures Research Articles

Factors associated with cardiac implantable electronic device-related infections, New South Wales, 2016-21: a retrospective cohort study.

To quantify the rate of cardiac implantable electronic device (CIED)-related infections and to identify risk factors for such infections. Retrospective cohort study; analysis of linked hospital admissions and mortality data. All adults who underwent CIED procedures in New South Wales between 1 January 2016 and 30 June 2021 (public hospitals) or 30 June 2020 (private hospitals). Proportions of patients hospitalised with CIED-related infections (identified by hospital record diagnosis codes); risk of CIED-related infection by patient, device, and procedural factors. Of 37 675 CIED procedures (23 194 men, 63.5%), 500 were followed by CIED-related infections (median follow-up, 24.9 months; interquartile range, 11.2-40.8 months), including 397 people (1.1%) within twelve months of their procedures, and 186 of 10 540 people (2.5%) at high risk of such infections (replacement or upgrade procedures; new cardiac resynchronisation therapy with defibrillator, CRT-D). The overall infection rate was 0.50 (95% confidence interval [CI], 0.45-0.54) per 1000 person-months; it was highest during the first month after the procedure (5.60 [95% CI, 4.89-6.42] per 1000 person-months). The risk of CIED-related infection was greater for people under 65 years of age than for those aged 65-74 years (adjusted hazard ratio [aHR], 1.71; 95% CI, 1.32-2.23), for people with CRT-D devices than for those with permanent pacemakers (aHR, 1.46; 95% CI, 1.02-2.08), for people who had previously undergone CIED procedures (two or more v none: aHR, 1.51; 95% CI, 1.02-2.25) or had CIED-related infections (aHR, 11.4; 95% CI, 8.34-15.7), or had undergone concomitant cardiac surgery (aHR, 1.62; 95% CI, 1.10-2.39), and for people with atrial fibrillation (aHR, 1.33; 95% CI, 1.11-1.60), chronic kidney disease (aHR, 1.54; 95% CI, 1.27-1.87), chronic obstructive pulmonary disease (aHR, 1.37; 95% CI, 1.10-1.69), or cardiomyopathy (aHR 1.60; 95% CI, 1.25-2.05). Knowledge of risk factors for CIED-related infections can help clinicians discuss them with their patients, identify people at particular risk, and inform decisions about device type, upgrades and replacements, and prophylactic interventions.

Safety of catheter ablation in patients with recently implanted cardiac implantable electronic device: A 5-year experience.

Catheter ablation (CA) can interfere with cardiac implantable electronic device (CIED) function. The safety of CA in the 1st year after CIED implantation/lead revision is uncertain. This single center, retrospective cohort included patients who underwent CA between 2012 and 2017 and had a CIED implant/lead revision within the preceding year. We assessed the frequency of device/lead malfunctions in this population. We identified 1810 CAs in patients between 2012 and 2017, with 170 CAs in 163 patients within a year of a CIED implant/lead revision. Mean age 68±12 years (68% men). Time between the CIED procedure and CA was 158±99 days. The CA procedures included AF ablation (n=57, 34%), AV node ablation (n=40, 24%), SVT ablation (n=37, 22%), and PVC/VT ablations (n=36, 21%). The cumulative frequency of lead dislodgement, significant CIED dysfunction, and/or CIED-related infection following CA was (n=1/170, 0.6%). There was a single atrial lead dislodgement (0.6%). There were no instances of power-on-reset or CIED-related infection. Following CA, there was no significant difference in RA or RV lead sensing (p=0.52 and 0.84 respectively) or thresholds (p=0.94 and 0.17 respectively). The RA impedance slightly decreased post-CA from 474±80 Ohms to 460±73 Ohms (p=0.002), as did the RV impedance (from 515±111 Ohms to 497±98 Ohms, p<0.0001). CA can be performed within 1 year following CIED implantation/lead revision with a low risk of CIED/lead malfunction or lead dislodgement. The ideal time to perform CA after a CIED remains uncertain.

Impact of clinical radiation audits on patient radiation exposure in cardiac implantable electronic device procedures

Impact of clinical radiation audits on patient radiation exposure in cardiac implantable electronic device procedures

Low-temperature electrocautery for high-risk cardiac implantable electronic device procedures.

Low-temperature electrocautery for high-risk cardiac implantable electronic device procedures.

Cephalic Vein Cutdown Is Superior to Subclavian Puncture as Venous Access for Patients with Cardiac Implantable Devices after Long-Term Follow-Up.

Cephalic vein cutdown (CVC) and subclavian vein puncture (SVP) are the most commonly used access sites for transvenous lead placement of cardiac implantable electronic devices (CIEDs). Limited knowledge exists about the long-term patency of the vascular lumen housing the leads. Among the 2703 patients who underwent CIED procedures between 2005 and 2013, we evaluated the phlebographies of 162 patients scheduled for an elective CIED replacement (median of 6.4 years after the first operation). The phlebographies were divided into four stenosis types: Type I = 0%, Type II = 1-69%, Type III = 70-99%, and Type IV = occlusion. Due to the fact that no standardized stenosis categorization exists, experienced physicians in consensus with the involved team made the applied distribution. The primary endpoint was the occurrence of stenosis Type III or IV in the CVC group and in the SVP group. In total, 162 patients with venography were enrolled in this study. The prevalence of high-degree stenosis was significantly lower in the CVC group (7/89, 7.8%) than in the SVP group (15/73, 20.5%, p = 0.023). In the CVC group, venographies showed a lower median stenosis (33%) than in the SVP group (median 42%). The present study showed that the long-term patency of the subclavian vein is higher after CVC than after SVP for venous access in patients with CIED.

Device infection in patients undergoing pacemaker or defibrillator surgery: risk stratification using the PADIT score.

The use of an antibacterial envelope is cost-effective for patients at high risk of developing cardiac implantable electronic device (CIED) infection. The identification of these high-risk patients may be facilitated using a clinical risk score. The aim of the current study is to evaluate the PADIT score for identifying high-risk patients in patients undergoing a CIED procedure in a tertiary academic center. This was a retrospective single-center study of consecutive patients undergoing a CIED procedure between January 2016 and November 2021. Patients who received an antibacterial envelope were excluded from this study. The primary endpoint was hospitalization for a CIED infection in the first year after the procedure. A total of 2333 CIED procedures were performed in the study period (mean age 61.6 ± 16.3years, male sex 64.5%, previous CIED infection 1.7%, immunocompromised 5.4%). The median PADIT score was 4 (interquartile range, 2-6). CIED infection occurred in 10 patients (0.43%). The PADIT score had good discrimination in predicting major CIED infection (C-statistic 0.70; 95% confidence interval [CI] 0.54 to 0.86, P = 0.03). Using an optimal PADIT score cut-off value of 7, the risk of CIED infection was higher in the patients with a PADIT score of ≥ 7 in comparison to those with a lower PADIT score (1.23% vs. 0.26%, P = 0.02; odds ratio 4.8, 95% CI 1.4 to 16.6, P = 0.01). The PADIT score is a clinically useful score for identifying patients at high risk of developing CIED infection. The use of an antibacterial envelope in these high-risk patients may be cost-effective.

Association between cardiac implantable electronic device infection and mortality: long-term follow up of a complete, state-wide cohort in Australia

Abstract Introduction The number of individuals with Cardiac Implantable Electronic Devices (CIEDs) is rising globally, and infection is a serious procedure-related complication. Only a limited number of studies based on population data have quantified the association between CIED infection and mortality, with inconsistent results. Purpose To assess the association between CIED infection and all-cause mortality in a large population-wide, contemporary cohort. Methods This retrospective cohort study used linked hospital and mortality data for New South Wales (NSW) residents. We studied all patients aged &amp;gt;18 years who underwent a CIED procedure in NSW public or private hospitals between January 2016 and June 2021. CIED infection was defined by the presence of relevant diagnosis codes in any hospitalisation following a CIED procedure. We followed the patients until their death or end of follow-up, whichever occurred first. Adjusted hazard ratios (aHR) with 95% confidence intervals (CIs) for associations of CIED infection with mortality were estimated using Cox regression at 1-year and end of follow-up, with CIED infection as a time-dependent variable. Results We followed 37,625 patients with CIED procedures (36% female, mean age (standard deviation [SD]) 75.4 [12.8] years) for an average [SD] of 2.3 [1.5] years. Of these patients, 500 (1.3%) had CIED infection, and 6,224 (16.5%) died during the study period. The overall mortality rate was 24.2% among those with an infection and 16.4% among those without an infection. Compared to other CIED patients, patients with CIED infection had a higher Kaplan-Meier mortality rate (17.0% vs. 7.1%) and adjusted hazard of mortality (aHR 2.43, 95%CI 1.84-3.21) at 12 months post-procedure. These differences were attenuated, but still remained significant at the end of follow-up (mortality rate 43.6% vs. 33.3%; aHR 1.66, 95%CI 1.39-1.99) (Figure 1). Conclusions In a complete, state-wide cohort of CIED patients, infection was associated with higher risks of both short- and medium-term mortality.Kaplan-Meier mortality by CIED infection

Abstract 15441: Impact of the COVID-19 Pandemic on Cardiac Implantable Electronic Device Procedures and Complications in the United States

Introduction: The impact of COVID-19 was felt across cardiology as resources were redirected to critical care, delaying elective cardiology procedures. Hypothesis: To evaluate differences in outcomes of cardiac implantable electronic device (CIED) procedures in 2020 (height of COVID) vs. 2016-2019 (pre-COVID). Methods: Adults &gt;= 18 years undergoing CIED procedures were identified from National Inpatient Sample Databases (NIS) 2016-2020. Complications and mortality were assessed based on the type of device: Permanent Pacemaker (PPM); Implantable Cardioverter Defibrillator (ICD); Cardiac Resynchronization Therapy with Pacemaker (CRT-P) or defibrillator (CRT-D): Leadless PPM; Generator explant (GE), and Lead extraction (LE). Results: A 13.8% drop in CIED admissions was recorded between 2019 and 2020 (p&lt;0.01). Fewer procedures involving PPM, ICD, CRT-P, CRT-D, LE, and GE were observed between 2019 and 2020. Leadless PPM utilization rose consistently between 2016-2020 (47.6% increase during 2020 vs 2019)(Figure). In 2020, a higher proportion of patients were classified with a Charlson Comorbidity Index score of ≥3 (severe) (47.4% in 2020 vs. 42.9% in 2016-2019, p&lt;0.01). The table shows significantly higher complications during CIED implants with no changes in mortality related to procedures. Conclusions: Patients admitted for CIED implants in 2020 had more severe comorbidities and expressed considerable differences in complications than pre-COVID era (2016-2019), but mortality remained unchanged. Leadless PPM use increased during pandemic, as against a decrease in the use of other CIEDs.

Abstract 12912: Effect of Real-Time Ambulatory Electrocardiography on Time-to-Intervention

Background: Mobile cardiac telemetry (MCT) and event monitors are ambulatory electrocardiography (AECG) monitors to aid in the detection/diagnosis of arrhythmias. They are unique in their real-time alerts to clinicians. This contrasts with Holter monitoring, which is continuous but where results are not available until after completion of the exam, uploading, and clinician over-read. There is limited data on relative benefit for time to electrophysiology procedure and interventions. Hypothesis: Does real-time monitoring of AECG reduce the time to cardiac implantable electronic device procedure, ablation procedure, or healthcare encounter when compared to AECG without real-time monitoring? Methods: This is a retrospective observational analysis of University of Utah Health patients who underwent AECG studies from 2010-2022. The study cohort was stratified by patients with an ambulatory ECG that provides real-time event notification (CEM and MCT; hereafter Non-holter) versus those that do not (Holter). The outcomes of interest were cardiac device implantation, ablation procedure, and ER/hospitalization within 12 months, analyzed based on time-to-event using log-rank tests. Results: We identified 50 patients in the Holter group and 137 for the Non-holter group. The groups had similar baseline characteristics in terms of age, gender, and co-morbidities. The mean number of days to device implant was 68.1 and 66.36, to ablation procedure was 77.68 and 67.77, and to ER/hospital visit was 61.12 and 55.38 in the Holter and Non-holter groups respectively (Figure). Conclusion: There was not a statistically significant difference between AECG monitoring in real-time (Non-holter) and those without (Holter), however, there was a trend toward decreased time to intervention in the Non-holter group for each of the three outcomes. Future, larger cohorts may provide adequate power to determine if real-time monitoring does reduce time to the studied interventions.

Aging and cardiac implantable electronic device complications: is the procedure safe in older patients?

In this study, we investigated whether there is a higher incidence of cardiac implantable electronic devices (CIED) procedures related complications in older (≥ 75years) than in younger (< 75years) patients. This retrospective cohort study enrolled patients who had undergone CIED procedures (de novo implantation, system upgrade, generator substitution, pocket revision or lead replacement) at two heart centers in Turkey between January 2011 and May 2023. The primary composite endpoint included clinically significant hematoma (CSH), pericardial effusion or tamponade, pneumothorax, and infection related to the device system. Secondary outcomes included each component of the composite end point. The overall sample included 1923 patients (1419 < 75years and 504 aged ≥ 75years). There was no difference between the groups in terms of cumulative events defined as primary outcome (3.5% vs. 4.4%, p = 0.393). Infection related to device system was significantly higher in the ≥ 75 age group (1.8% vs. 3.4%, p = 0.034). There was no significant difference between the groups in terms of clinically significant hematoma and pneumothorax (0.7% vs. 0.4%, p = 0.451, 1.4% vs. 1.0%, p = 0.477, respectively). In multivariate model analysis, no association was found between age ≥ 75years and infection related to the device system. Infection rates were relatively higher in the patient group aged ≥ 75years. This patient group should be evaluated more carefully in terms of infection development before and after the procedure.

Cardiac implantable electronic device procedure history as the most important predictor of poor 2-year survival after transcatheter aortic valve replacement.

Cardiac implantable electronic device procedure history as the most important predictor of poor 2-year survival after transcatheter aortic valve replacement.

Low incidence rate of infections associated with cardiac implantable electronic device procedures in a large real-world patient cohort

Abstract Funding Acknowledgements Type of funding sources: None. Background The incidence of death and infections in patients implanted with cardiac implantable electronic devices (CIEDs) are not fully known yet (1,2). Purpose To describe the incidence of death and device’s infection and its potential predictors in a contemporary cohort of CIED patients. Methods All consecutive patients implanted with a CIED at our tertiary institution were prospectively enrolled. Follow-up was performed every six months and clinical events recorded by expert electrophysiologists. For the purpose of the present analysis, we considered patients with a potential follow-up of at least 24 months. Results Between 01/09/2018 and 01/09/2020, a total of 838 patients were enrolled (34.6% female; age 77 [70-84]; PADIT score 2 [2-4]). Pacemaker (PM) and implantable cardioverter defibrillator (ICD) or cardiac resynchronization therapy and defibrillator (CRT-D) were implanted in 569 (68%) and 269 (32%) patients respectively. All patients had pre-implant antibiotic prophylaxis and 5.5% had an antibiotic-eluting envelope. Follow-up data were available for 832 (99.2%) patients. After a median follow-up of 42.3 (30.2-56.4) months, 212 (25.5%) patients died and 5 (0.6%) had a CIED infection. Four out of five patients required CIED extraction, while 1 patient antibiotics only. At multivariate Cox-regression analysis, age (hazard ratio [HR] 1.08; 95% confidence interval [CI] 1.05-1.10) and dialysis (HR 6.18; 95%CI 3.40-11.25) were independently associated with death, while first implant was associated with a lower risk as compared to subsequent procedures (HR 0.63; 95%CI 0.46-0.85) (Figure 1). Conclusions In large contemporary cohort of CIED patients, mortality was substantially high and associated with clinical factors depicting a population at risk. On the other hand, the incidence of CIED infections was low.

PO-02-059 INFLAMMATORY REACTION TO ANTIBIOTIC ELUTING POUCH MASQUERADING AS RECURRENT CARDIAC IMPLANTABLE ELECTRONIC DEVICE INFECTION

Absorbable antibacterial envelopes mitigate risk of pocket infections during repeat cardiac implantable electronic device (CIED) procedures. Despite use of antibacterial envelopes, risk of CIED infection persists. However, hallmark signs of CIED infection including incisional erythema, drainage, and wound dehiscence overlap with a less common clinical entity – allergic reaction. To present a case of recurrent CIED wound dehiscence secondary to an inflammatory response to the antibacterial envelope proven with histological evaluation. N/A A 52-year-old male with remote aortic valve replacement complicated by complete heart block and a dual chamber pacemaker (DC PPM) underwent generator change with use of a Tyrx antibacterial pouch. One week later, he developed partial wound dehiscence and cloudy incisional drainage. The patient was started on antibiotic therapy and underwent percutaneous system extraction with placement of an externalized right ventricular lead. Pocket cultures were negative. A contralateral DC PPM was inserted with a Tyrx pouch. The patient completed a course of antibiotics. Within two weeks of placement, he presented with recurrent wound dehiscence. The new device was removed with a pathologic specimen obtained from the presumably infected pocket and an externalized pacing lead was placed. Cultures were again negative. The pathologic specimen demonstrated foreign body response with lymphoplasmacytic and focal neutrophilic inflammation most consistent with allergic reaction. The patient underwent implantation of a low-lateral left-sided DC PPM distant from the prior site without the use of a Tyrx antibacterial envelope. The patient was discharged without antibiotics with no evidence of infection or inflammation at the new site over a follow up period of 6-months. Allergic reaction to Tyrx antibiotic envelope should be considered with wound dehiscence, particularly if recurrent. Tissue biopsy with foreign body response can elucidate an allergic mechanism.

Treatment with gentamicin-impregnated collagen sponges in reducing infection of implantable cardiac devices: 10-year analysis with propensity score matching

Introduction and ObjectivesThe incidence of device infection has increased over time and is associated with increased mortality in patients with cardiac implantable electronic devices (CIEDs). Gentamicin-impregnated collagen sponges (GICSs) are useful in preventing surgical site infection (SSI) in cardiac surgery. Nevertheless, to date, there is no evidence concerning their use in CIED procedures. Our study aims to determine the effectiveness of treatment with GICSs in preventing CIED infection. MethodsA total of 2986 adult patients who received CIEDs between 2010 and 2020 were included. Before device implantation, all patients received routine periprocedural systemic antibiotic prophylaxis. The study endpoints were the CIED infection rate at one year and the effectiveness of the use of GICSs in reducing CIED infection. ResultsAmong 1524 pacemaker, 942 ICD and 520 CRT implantations, CIED infection occurred in 36 patients (1.2%). Early reintervention (OR 9 [95% CI 3.180–25.837], p<0.001), pocket hematoma (OR 11 [95% CI 4.195–28.961], p<0.001), diabetes (OR 2.9 [95% CI 1.465–5.799], p=0.002) and prolonged procedural time (OR 1.02 [95% CI 1.008–1.034], p=0.001) were independent risk factors for CIED infection. Treatment with GICSs reduced CIED infections significantly ([95% CI −0.031 to −0.001], p<0.001). ConclusionsThe use of GICSs may help in reducing infections associated with CIED implantation.

Contemporary trends in cardiac electrophysiology procedures in the United States, and impact of a global pandemic.

There are limited data on trends in nationwide cardiac electrophysiology (EP) procedures in the United States before and during the global COVID-19 pandemic. We aimed to understand contemporary EP procedural trends and how the COVID-19 pandemic impacted them. Trends were obtained from publicly reported Centers for Medicare and Medicaid Services data from 2013 to 2020 (latest available). Rates of catheter-based EP procedures (EP studies and ablations) and cardiac implantable electronic device (CIED) procedures were analyzed. All procedural rates were calculated per 100,000 Medicare beneficiaries (year specific). Procedure physician subspecialty was also reported. From 2013 to 2019, annual rate of all cardiac EP procedures increased from 817.91 to 1089.68 per 100,000 beneficiaries. Catheter-based EP procedures increased from 323.73 to 675.01, while CIED rates decreased from 494.18 to 414.67. While all ablation procedures increased over time, relative proportion of ablation procedures being pulmonary vein isolation (PVI) increased (9.9% of ablations in 2013, to 18.2% in 2019). In 2020, rates of both catheter-based EP procedures and CIED procedures decreased; however, PVI share of ablation continued to increase in 2020 comprising 25.2% of ablation procedures. Rates of EP procedures have increased among Medicare beneficiaries, with catheter-based procedures now eclipsing CIEDs. Additionally, a greater proportion of catheter-based EP procedures are PVI, but they still represent a minority of all ablations. In 2020, rates of EP procedures were attenuated, yet the proportion of PVI ablations increased to over one-fourth of ablation procedures. These data have important implications for the EP workforce.

Ultrasound-guided vascular access for CIED implantation: A step-by-step guide.

Vascular access is required for most cardiac electrophysiology procedures. Over the past 2 decades, ultrasound guidance has increased in utilization as the primary method for assisting operators in gaining access to cardiac implantable electronic device (CIED) implantation. Ultrasound guidance using a technique that includes both short-axis and long-axis views combined with a twisting needle motion after maximal tenting provides an extremely safe and reproducible technique for vascular access for all CIED procedures. In this manuscript and accompanying videos, a step-by-step guide is explained for optimal ultrasound-guided visualization and needle maneuver technique to maximize safety and efficiency for vascular access in all CIED procedures.

Predictors of Early Cardiac Implantable Electronic Device Lead Dislodgement in the Elderly.

One of the most frequent cardiac implantable electronic device (CIED) implantation complications is lead dislodgement, especially in the older adult population. Little evidence is available about the influence of frailty on the risk of lead dislodgment after CIED implantation procedures; thus, the evaluation of frailty could be relevant for the course and safety of the implantation procedure, especially among the elderly with cardiovascular diseases. This study aimed to assess the risks and predictors of early lead dislodgement in the elderly population. Between 2008 and 2021, 14,293 patients underwent implantations. In 400 elderly patients, lead dislodgement was confirmed, and frailty was retrospectively calculated. The most frequent dislodgement according to the lead position was that of the atrial lead (133; 33.3%). In the logistic regression, frailty (OR: 1.8196, 95% CI:1.4991-2.2086; p < 0.0001) and age (OR: 1.0315, 95% CI:1.0005-1.0634; p < 0.0461) were independent predictors of early dislodgement. In the female group, frailty (OR: 2.1185, 95% CI: 1.5530-2.8899; p < 0.0001) was an independent predictor of early dislodgement. Similarly, in the male group, frailty (OR: 1.6321, 95% CI:1.2725-2.0934; p < 0.0001) was an independent predictor of early dislodgement. Lead dislodgement often occurs in the elderly. Frailty in both men and women is a predictive factor of early lead dislodgment. Evaluating frailty may be an essential element of proper selection, especially in the elderly undergoing CIED procedures, and, consequently, it could help prevent further complications.

Abstract 9696: Long-Term Outcomes With Abandoning versus Extracting Sterile Leads: A 10-Year Population-Based Study

Background: Long-term outcomes of lead management strategies of lead abandonment (LA) or transvenous lead extraction (TLE) during cardiac implantable electronic devices (CIED) procedures requiring lead addition or replacement remain unclear. Hypothesis: We hypothesized that there is no difference in long-term (10-year) outcomes of LA versus TLE during CIED procedures requiring lead addition. Methods: We performed a retrospective cohort study of a population residing in seven adjacent counties of southeastern Minnesota with follow-up at the Mayo Clinic and its health systems. Patients who underwent LA or TLE for sterile leads from January 1, 2000, to January 1, 2011, and had follow-up for at least 10-years or until their death were included. Outcomes were identified through a detailed chart review of the electronic health record from within the Mayo Clinic system. Results: A total of 172 patients were included in the study with 153 patients who underwent LA and 19 who underwent TLE for sterile leads. In long-term follow-up, indications for subsequent lead extraction arose in 9.1% (n=14) of patients with initial LA and 5.3% (n=1) in patients with initial TLE, after an average of 7-years. Moreover, out of 14 patients, who required secondary extraction in the LA cohort, 28.6% did not proceed with the extraction. Of the remaining 10 patients, 60% had clinical success and 40% had a clinical failure with the extraction. Subsequent device upgrades or revisions were performed in 18.3% of patients in the LA group and 31.6% in the TLE group, with no significant differences in procedural challenges such as requiring balloon venoplasty or serial dilation (5.2% vs. 5.3%, P=1.0). There was no difference in 10-year survival probability among LA group and TLE group (P=0.64). Conclusion: Indications for subsequent extraction arose in 9.1% of patients with the initial LA approach for sterile leads after an average of 7.3 years and 28.6% did not proceed with the extraction. Of the patients who underwent the subsequent extraction, 60% had clinical success and 40% had a clinical failure. There was no difference in 10-year survival probability between patients with the initial LA approach or TLE approach.

Risk Factors of Haematoma Formation Following Cardiac Implantable Electronic Device Procedures.

A single-centre cohort of 2,100 adults who consecutively underwent cardiac implantable electronic device procedures were retrospectively analysed to identify and quantify risk factors of perioperative pocket haematoma formation. Dual antiplatelet therapy was significantly associated with increased odds of haematoma formation (OR 11.7 for aspirin and clopidogrel, OR 11.8 for aspirin and ticagrelor and OR 104 for aspirin and prasugrel, p<0.05) on multivariate binomial logistic regression analysis. Aspirin monotherapy was also associated with increased bleeding risk (OR 3.02, p<0.01). Direct oral anticoagulants and warfarin were also each associated with increased odds of haematoma formation although to a lesser extent than dual anti platelet therapy (DAPT). Amongst oral anticoagulants, apixaban was associated with the lowest bleeding risk (OR 2.59, p=0.03) whilst dabigatran was associated with the highest (OR 3.81, p=0.04). There was a significant incremental reduction in bleeding risk by 8% per 10x103/μL increase in platelet count. DAPT was associated with increased odds of pocket haematoma formation following cardiovascular implantable electronic device (CIED) procedure. This likelihood was higher than with oral anticoagulation therapy. Timely medication reconciliation of P2Y12 inhibitors according to guidelines is important to avoid post-procedural bleeding complications. Perioperative policies which account for the half-life of withheld anticoagulant agents may help reduce the haematoma risk.

Pocket histology at cardiac implantable electronic device replacement: What’s new?

Repeated procedures involving the cardiac implantable electronic device (CIED) pocket increase the infection risk, and the extent of pocket adhesions may prolong the procedure time. Few data on pocket histology at the time of CIED replacement are available. The purpose of this study was to describe CIED pocket histology in a cohort of patients undergoing CIED replacement or upgrade. All consecutive patients undergoing CIED replacement or upgrade at our center between November 2019 and May 2020 were enrolled. Subclinical pocket infection was ruled out by physical inspection and laboratory parameters before the procedure. Pocket tissue specimens from the anterior and posterior pockets were obtained intraoperatively. A systematic histological analysis of capsular thickness, fibrous connective tissue, neovascularization, inflammation, and calcifications was performed. Thirty patients (6 women, 20%) were enrolled. The mean capsular thickness was 0.8 ± 0.3 mm in the anterior wall and 1.1 ± 0.4 mm in the posterior wall. Subcapsular fibrosis was mild and multifocal in the anterior wall and moderate and focal in the posterior wall. Neovascularization was focal in most cases, and vessel remodeling mainly involved the tunica media. Chronic inflammation was usually mild and nongranulomatous, and in a quarter of cases, subacute exudative fibrous inflammation was detected in the posterior pocket wall. The CIED pocket is a histopathologically dynamic environment, given the coexistence of both a subacute foreign body response and fibrous tissue growth, implying continuous remodeling due to an injury-repair mechanism. Strategies to interact with foreign body response might minimize inflammatory pocket activity, especially device encapsulation by tight fibrous tissue, and possibly complications related to repeated CIED procedures.