Isolation of the superior vena cava by ultra-low temperature cryoablation

A patient with shocks from his ICD related to AF underwent redo ablation. The only identifiable target was the superior vena cava. This was isolated using ultra-low cryotherapy, eliminating episodes of AF.

Transvenous lead extraction: Experience of the Tandem approach

AIMS

Transvenous lead extraction (TLE) is important in the management of cardiac implantable electronic devices but carries risk. It is most commonly completed from the superior access, often with 'bail-out' support via the femoral approach. Superior and inferior access may be used in tandem, which has been proposed as an advance in safety and efficacy. The aim of this study is to evaluate the safety and efficacy of the Tandem approach.

METHOD

The 'Tandem' procedure entailed grasping of the targeted lead in the right atrium to provide countertraction as a rotational dissecting sheath was advanced over the lead from the subclavian access. Consecutive 'Tandem' procedures performed by a single operator between December 2020 and March 2023 in a single large-volume TLE centre were included and compared with the conventional superior approach (control) using 1:1 propensity score matching; patients were statistically matched for demographics.

RESULTS

The Tandem in comparison with the conventional approach extracted leads of much greater dwell time (148.9 ± 79 vs. 108.6 ± 77 months, P < 0.01) in a shorter procedure duration (96 ± 36 vs. 127 ± 67 min, P < 0.01) but requiring more fluoroscopy (16.4 ± 10.9 vs. 10.8 ± 14.9 min, P < 0.01). The Tandem and control groups had similar clinical (100% vs. 94.7%, P = 0.07) and complete (94.8% vs. 92.8%, P = 0.42) success, with comparable minor (4% vs. 6.7%, P = 0.72) and major (0% vs. 4%, P = 0.25) complications; procedural (0% vs. 1.3%, P = 1) and 30-day (1.3% vs. 4%, P = 0.62) mortality were also similar.

CONCLUSION

The Tandem procedure is as safe and effective as the conventional TLE. It can be applied to leads of a long dwell time with a potentially shorter procedure duration.

Comparison of non-laser and laser transvenous lead extraction: a systematic review and meta-analysis

AIMS

Transvenous lead extraction (TLE) is performed using non-laser and laser techniques with overall high efficacy and safety. Variation in outcomes between the two approaches does exist with limited comparative evidence in the literature. We sought to compare non-laser and laser TLE in a meta-analysis.

METHODS AND RESULTS

We searched Medline, Embase, Scopus, ClinicalTrials.gov, and CENTRAL databases for TLE studies published between 1991 and 2021. From the included 68 studies, safety and efficacy data were carefully evaluated and extracted. Aggregated cases of outcomes were used to calculate odds ratio (OR), and pooled rates were synthesized from eligible studies to compare non-laser and laser techniques. Subgroup comparison of rotational tool and laser extraction was also performed. Non-laser in comparison with laser had lower procedural mortality (pooled rate 0% vs. 0.1%, P < 0.01), major complications (pooled rate 0.7% vs. 1.7%, P < 0.01), and superior vena cava (SVC) injury (pooled rate 0% vs. 0.5%, P < 0.001), with higher complete success (pooled rate 96.5% vs. 93.8%, P < 0.01). Non-laser comparatively to laser was more likely to achieve clinical [OR 2.16 (1.77-2.63), P < 0.01] and complete [OR 1.87 (1.69-2.08), P < 0.01] success, with a lower procedural mortality risk [OR 1.6 (1.02-2.5), P < 0.05]. In the subgroup analysis, rotational tool compared with laser achieved greater complete success (pooled rate 97.4% vs. 95%, P < 0.01) with lower SVC injury (pooled rate 0% vs. 0.7%, P < 0.01).

CONCLUSION

Non-laser TLE is associated with a better safety and efficacy profile when compared with laser methods. There is a greater risk of SVC injury associated with laser sheath extraction.

Progress in Cardiac Resynchronisation Therapy and Optimisation

Cardiac resynchronisation therapy (CRT) has become the cornerstone of heart failure (HF) treatment. Despite the obvious benefit from this therapy, an estimated 30% of CRT patients do not respond ("non-responders"). The cause of "non-response" is multi-factorial and includes suboptimal device settings. To optimise CRT settings, echocardiography has been considered the gold standard but has limitations: it is user dependent and consumes time and resources. CRT proprietary algorithms have been developed to perform device optimisation efficiently and with limited resources. In this review, we discuss CRT optimisation including the various adopted proprietary algorithms and conduction system pacing.

Transvenous Lead Extraction: Work in Progress

Cardiac implantable electronic devices are the cornerstone of cardiac rhythm management, with a significant number of implantations annually. A rising prevalence of cardiac implantable electronic devices coupled with widening indications for device removal has fuelled a demand for transvenous lead extraction (TLE). With advancement of tools and techniques, the safety and efficacy profile of TLE has significantly improved since its inception. Despite these advances, TLE continues to carry risk of significant complications, including a superior vena cava injury and mortality. However, innovative approaches to lead extraction, including the use of the jugular and femoral accesses, offers potential for further gains in safety and efficacy. In this review, the indications and risks of TLE are discussed while examining the evolution of this procedure from simple traction to advanced methodologies, which have contributed to a significant improvement in safety and efficacy.

Effect of esophageal cooling on ablation lesion formation in the left atrium: Insights from Ablation Index data in the IMPACT trial and clinical outcomes

INTRODUCTION

The IMPACT study established the role of controlled esophageal cooling in preventing esophageal thermal injury during radiofrequency (RF) ablation for atrial fibrillation (AF). The effect of esophageal cooling on ablation lesion delivery and procedural and patient outcomes had not been previously studied. The objective was to determine the effect of esophageal cooling on the formation of RF lesions, the ability to achieve procedural endpoints, and clinical outcomes.

METHODS

Participants in the IMPACT trial underwent AF ablation guided by Ablation Index (30 W at 350-400 AI posteriorly, 40 W at ≥450 AI anteriorly). A blinded 1:1 randomization assigned patients to the use of the ensoETM® device to keep esophageal temperature at 4°C during ablation or standard practice using a single-sensor temperature probe. Ablation parameters and clinical outcomes were analyzed.

RESULTS

Procedural data from 188 patients were analyzed. Procedure and fluoroscopy times were similar, and all pulmonary veins were isolated. First-pass pulmonary vein isolation and reconnection at the end of the waiting period were similar in both randomized groups (51/64 vs. 51/68; p = 0.54 and 5/64 vs. 7/68; p = 0.76, respectively). Posterior wall isolation was also similar: 24/33 versus 27/38; p = 0.88. Ablation effect on tissue, measured in impedance drop, was no different between the two randomized groups: 8.6Ω (IQR: 6-11.8) versus 8.76Ω (IQR: 6-12.2; p = 0.25). Arrhythmia recurrence was similar after 12 months (21.1% vs. 24.1%; 95% CI: 0.38-1.84; HR: 0.83; p = 0.66).

CONCLUSIONS

Esophageal cooling has been shown to be effective in reducing ablation-related thermal injury during RF ablation. This protection does not compromise standard procedural endpoints or clinical success at 12 months.

Protecting Against Collateral Damage to Non-cardiac Structures During Endocardial Ablation for Persistent Atrial Fibrillation

Injury to structures adjacent to the heart, particularly oesophageal injury, accounts for a large proportion of fatal and life-altering complications of ablation for persistent AF. Avoiding these complications dictates many aspects of the way ablation is performed. Because avoidance involves limiting energy delivery in areas of interest, fear of extracardiac injury can impede the ability of the operator to perform an effective procedure. New techniques are becoming available that may permit the operator to circumvent this dilemma and deliver effective ablation with less risk to adjacent structures. The authors review all methods available to avoid injury to extracardiac structures to put these developments in context.

Economic Evaluation of Catheter Ablation Versus Medical Therapy for the Treatment of Atrial Fibrillation from the Perspective of the UK

Randomised evidence supports an early rhythm control strategy as treatment for AF, and catheter ablation outperforms medical therapy in terms of effectiveness when studied as first- and second-line treatment. Despite evidence consistently showing that catheter ablation treatment is superior to medical therapy in most AF patients, only a small proportion receive ablation, in some cases after a prolonged trial of ineffective medical therapy. Health economics research in electrophysiology remains limited but is recognised as being important in influencing positive change to ensure early access to ablation services for all eligible patients. Such information has informed the updated recommendations from the recently published National Institute for Health and Care Excellence clinical guideline on the diagnosis and management of AF, but increased awareness is needed to drive real-world adoption and to ensure patients are quickly referred to specialists. In this article, economic evaluations of catheter ablation versus medical therapy are reviewed.

New approaches to achieving hemostasis after venous access in cardiovascular patients

Recent decades have seen a series of advances in percutaneous transvenous procedures for cardiac arrhythmias, including the implantation of leadless pacemakers. Many of these procedures require the insertion of large caliber sheaths in large veins, usually the femoral vein. Securing hemostasis efficiently and reliably at the access site is a key step to improving a procedure's safety profile. Traditionally, hemostasis was achieved by manual compression of venous access sites, but the trend toward larger sheaths and the increased use of uninterrupted anticoagulation has pushed the limits of this method. Achieving hemostasis by compression alone in these circumstances requires more attention and longer duration, leading to greater patient discomfort and prolonged immobility. In turn, manual compression may be more time-consuming for medical professionals and increase the number of occupied hospital beds. New approaches have been developed to facilitate early ambulation, decrease patient discomfort, and address the risk of access site complications. These approaches include vascular closure devices and subcutaneous suture techniques including figureof- eight and purse-string sutures. This article reviews the new approaches applied to achieve venous access site hemostasis in patients undergoing transvenous procedures for cardiac arrhythmias.

Triple access transvenous lead extraction: Pull-through of a lead from subclavian to jugular access to facilitate extraction

A 39-years old ventricular lead of a right-sided single-chamber pacemaker required extraction for infection. Angulation at the right subclavian-superior vena cava junction coupled with calcified fibrotic encapsulating tissue prevented advancement of a rotational dissecting sheath. To straighten the lead, it was pulled from the subclavian and out of the right internal jugular vein, whilst the Needle's-Eye Snare via the femoral access provided counter-traction. A 13-french rotational dissecting sheath was successfully advanced over the lead via the jugular access to complete the lead extraction without any complication.

Anatomical variations in coronary venous drainage: challenges and solutions in delivering cardiac resynchronisation therapy

Funding Acknowledgements

Type of funding sources: None.

Background

Cardiac resynchronisation therapy (CRT) is the cornerstone of heart failure management. Delivery of a left ventricular lead can occur in a small proportion of patients undermining the benefits of this treatment. Abnormal coronary venous anatomy is a contributing factor to this failure. Although epicardial lead placement is available, this patient cohort requiring CRT is subject to higher peri-operative morbidity and mortality than the general population; a transvenous approach is preferable.

Purpose

To investigate the abnormalities of the coronary venous system in candidates for cardiac resynchronization therapy (CRT) and describe methods for circumventing the resulting difficulties.

Methods

From 4 implanting institutes, data of all CRT implants between October 2008-October 2020 were screened for abnormal cardiac venous anatomy, defined as an anatomical variation not conforming to the accepted ‘normal’ anatomy. Patient demographics, procedural detail and subsequent left ventricle (LV) lead pacing indices were collected.

Results

From a total of 3548 CRT implants, 15 (0.42%) patients (80% male) of 72.2±10.6 years in age with a LV ejection fraction of 34±10.3% were identified to have had an abnormal cardiac venous anatomy over the study period. There were 13 cases of persistent left side superior vena cava (pLSVC), 5 of which had coronary sinus ostium atresia (CSOA) including 2 with an ‘unroofed’ coronary sinus (CS); 1 patient had a unique anomalous origin of the CS and 1 patient had an isolated CSOA. In total 14 patients (60% repeat attempt) had successful percutaneous implant under general anaesthesia (46.7%) via the cephalic vein (59.1%), using the femoral approach (53.3%) for levophase venography and/or pull-through, including 1 case of endocardial LV implant. Pacing follow-up over 37.64±37.6 months demonstrated LV lead threshold between 0.62-2.9 volts (pulsewidth 0.4-1.5 milliseconds) in all cases; 5 patients died within 2.92±1.6 years of successful implant.

Conclusion

CRT devices can be implanted percutaneously even in the presence of substantial abnormalities of coronary venous anatomy. Alternative routes of venous access may be required.

Transvenous lead extraction: the Tandem approach

Funding Acknowledgements

Type of funding sources: None.

Background

Transvenous lead extraction (TLE) has become an important strategy in the management of patients with cardiac implantable electronic devices (CIEDs). A rising population of patients with CIEDs coupled with an expanding indication for TLE, has fuelled demand. There are notable procedural risks however development of techniques and tools have contributed to an improvement in the safety and efficacy of TLE. The mechanical rotational dissecting sheath is safe and efficacious whilst the Needle’s Eye Snare (NES) is an additional ‘bail-out’ strategy contributing to procedural success.

Purpose

We sought to evaluate the outcomes of TLE performed from the superior access in conjunction with counter-traction provided by snaring of the targeted lead via the femoral access.

Method

The ‘Tandem’ procedure consisted of the rotational powered sheath performing dissection of the adhesions encapsulating the leads (at the superior access), in ‘Tandem’ with the Needle’s Eye Snare providing countertraction via the femoral vein. In brief: after deployment of the locking stylet in the lead lumen, the NES was used to grasp the lead in the right atrium and hold it tort while a rotational sheath was used to dissect through the veins. Once the sheath reached the right atrium, the lead was released from the snare and the sheath was used to continue dissection toward the lead tip. Data for all consecutive ‘Tandem’ procedures performed between 1/1/2021 – 1/1/2022 in our high-volume TLE institute were collected and evaluated for safety and efficacy.

Results

Forty patients aged 69.2±16.3 (70% male), underwent TLE of 75 leads (45 right ventricle, 25, right atrium, 5 left ventricle) with dwell time of 150.1±80.3 months for a non-infectious indication (65%). Of the 40 cases, 27 were hypertensives, 14 had ischaemic heart disease whilst 5 suffered diabetes with a left ventricle ejection fraction of 46.8±10.2%; 12 (30%) were pacing dependent. Procedures were performed by cardiologists in the cardiac catheterisation suite under general anaesthesia (95%) using a locking stylet (100%) with an Evolution RL (11-french 58.7%); a NES 13 millimetres curve (88%) was used to successfully snare 91% of the targeted leads. Complete procedural success was achieved in 92% of leads with 98.7% clinical success. Minor complications occurred in 2 cases (pneumothorax, pocket haematoma requiring intervention), in the absence of any major complications or peri-procedural mortality; there was no 30-day mortality.

Conclusion

The ‘Tandem’ procedure provides an additional strategy to improve the safety and efficacy of TLE, especially in leads of a long dwell time.

Oesophageal protection during AF ablation: real world registry data and mechanisms behind the therapeutic effect of tissue cooling

Funding Acknowledgements

Type of funding sources: None.

Background

Oesophageal protection using a dedicated device to provide controlled active thermal protection of the oesophagus during atrial fibrillation ablation has been shown to be effective at reducing endoscopically detected oesophageal lesions. Real world registry data of this device and established evidence on the effect of cooling on localized tissue after thermal injury have been under review.

Purpose

To determine the safety of an oesophageal temperature control device by a review of real-world registry data on its clinical use during catheter ablation procedures and to clarify basic mechanisms of its therapeutic action by a literature review of scientific studies on cooling in the context of thermal injury.

Methods

The United States Food and Drug Administration (FDA) Manufacturer and User Facility Device Experience (MAUDE), FDA Medical and Radiation Emitting Device Recalls, the Medicines and Healthcare products Regulatory Agency (MHRA) Medical Device Alerts and SwissMedic records of Field Safety Corrective Actions (FSCA) databases were reviewed for any device-related adverse events. A systematic literature review was conducted to clarify the findings from studies investigating the physiological processes behind the therapeutic effect of cooling after tissue thermal injury.

Results

Of over 20,000 oesophageal temperature control devices clinically used, 7976 were recorded as having been used for the purpose of oesophageal protection during left atrial catheter ablations. No adverse events occurred related to its use during left atrial catheter ablations. No case of clinically significant oesophageal injury was reported in a patient who had been protected by the oesophageal temperature control device. 208 research articles retrieved from PubMed and MEDLINE that met the search criteria were reviewed. The common finding in all the studies was that cooling had an anti-inflammatory and restorative effect via modulation of several immune-mediated pathways, local cellular function and genetic expression.

Conclusions

There have been no adverse events reported to date in real world clinical use of an oesophageal temperature control device during left atrial catheter ablations, for the purpose of active thermal protection. Literature review data suggests that there are complex biophysical and cellular effects from cooling that leads to its therapeutic effect but further work is required to define the mechanisms of action of thermal protection in this specific context.

Randomised comparison of achieve and traditional circular mapping catheters in cryoballoon ablation: results at up to a decade

Funding Acknowledgements

Type of funding sources: None.

Background

A single-centre trial randomised patients to the use of the Achieve mapping catheter or a traditional circular mapping catheter during cryoballoon procedures for paroxysmal atrial fibrillation (AF) in 2011-2014. Long-term outcomes from the cohort were determined in 2021.

Purpose

To evaluate the determinants of long-term outcome of ablation for paroxysmal AF.

Methods

Patient and study procedure characteristics and clinical outcomes were determined, including mapping catheter assignment, model of cryoballoon used, AF recurrence, repeat ablations required, findings at repeat ablation long term survival of the patient.

Results

Of 102 patients in the original study, 98 had long-term (4.11+/-2.82 years) follow up data available. 35 patients (35.7%) had AF recurrence, giving a long-term success rate at 64.3% after 1 ablation, increasing to 81.6% after repeat ablation. Of the study cohort n=8 (8.16%) died at a median of 4.9 years after ablation (IQR:1.7-5.7). 25/98 (25.5%) patients had a second ablation and 7 (7.1%) had a third or more ablations. Those who had AF recurrence were older, with a higher prevalence of prior ischaemic heart disease and cardiac device implantation (p=0.02-0.03). After multi-variate analysis, a prior implanted cardiac device was the only significant predictor of recurrence (p=0.03).

Conclusion

Long-term outcomes after a 1st time PAF cryoablation were similar regardless of the type of mapping catheter used, the generation of cryoballoon, and traditional procedure endpoints. AF recurrences were more often detected in older patients with a history of ischaemic heart disease and implanted cardiac devices.

Tunnelled dialysis catheter extraction: a cardiology experience

Funding Acknowledgements

Type of funding sources: None.

Background

Tunnelled dialysis catheters are integral to the management of patients with chronic kidney disease (CKD), providing a means to dialysis. They are prone to blockages necessitating removal. Most catheters are removed with manual traction without any sequalae by renal physicians whilst a small proportion require further intervention which may include interventional radiology or an ‘open’ surgical removal which carries additional risk. Cardiologists versed in transvenous lead extraction (TLE) provide an additional strategy.

Purpose

To evaluate the outcomes of tunnelled dialysis catheter ‘extractions’ performed by cardiologists at a high-volume TLE institute.

Method

All consecutive patients referred to cardiologists (1/10/2016 – 1/10/21) for extraction of tunnelled dialysis catheters following an unsuccessful attempt by the renal physicians and interventional radiology, were included in this series. Data of procedural outcomes was evaluated for safety and efficacy.

Results

Twelve patients (7 male) aged 64.15±15.04 years with a body mass index of 28.3 kg/m2 were referred for tunnelled catheter extraction for non-functioning lines (75%). Of these 12 CKD patients, the aetiology included focal segmental glomerulosclerosis (n=2), hypertension (n=2), diabetes (n=1) and sickle cell disease (n=1). In total, 12 tunnelled catheters (75%; n=9 right side) were completely removed (100%) using local anaesthesia (83.3%) in a procedure lasting 54.7±29.8 minutes and requiring 0.79±1.32 minutes of fluoroscopy. Eleven patients (91.7%) had their catheters successfully extracted with manual traction alone; 3 necessitated the use of a 0.035 stiff J-tip wire whilst one required the use of a rotational dissecting sheath Evolution (Cook Medical, USA). Of the 12 cases, 11 had a failed previous attempt including 1 patient who suffered a ventricular fibrillation cardiac arrest during the procedure and 1 was referred directly without an attempt as there was a concurrent pacemaker situated from the contralateral side; 4 patients had new lines placed and no significant complications occurred. There were no complications or procedural mortality.

Conclusion

Extraction of tunnelled dialysis catheter lines performed by cardiologists is safe and efficacious; experience in TLE is vital. This may provide an additional strategy for removal of these catheters when other percutaneous attempts fail.

Anatomical variations in Coronary Venous Drainage: Challenges and Solutions in Delivering Cardiac Resynchronisation Therapy

AIMS

To investigate the abnormalities of the coronary venous system in candidates for cardiac resynchronization therapy (CRT) and describe methods for circumventing the resulting difficulties.

METHODS

From 4 implanting institutes, data of all CRT implants between October 2008-October 2020 were screened for abnormal cardiac venous anatomy, defined as an anatomical variation not conforming to the accepted 'normal' anatomy. Patient demographics, procedural detail and subsequent left ventricle (LV) lead pacing indices were collected.

RESULTS

From a total of 3548 CRT implants, 15 (0.42%) patients (80% male) of 72.2±10.6 years in age with a LV ejection fraction of 34±10.3% were identified to have had an abnormal cardiac venous anatomy over the study period. There were 13 cases of persistent left side superior vena cava (pLSVC), 5 of which had coronary sinus ostium atresia (CSOA) including 2 with an 'unroofed' coronary sinus (CS); 1 patient had a unique anomalous origin of the CS and 1 patient had an isolated CSOA. In total 14 patients (60% repeat attempt) had successful percutaneous implant under general anaesthesia (46.7%) via the cephalic vein (59.1%), using the femoral approach (53.3%) for levophase venography and/or pull-through, including 1 case of endocardial LV implant. Pacing follow-up over 37.64±37.6 months demonstrated LV lead threshold between 0.62-2.9 volts (pulsewidth 0.4-1.5 milliseconds) in all cases; 5 patients died within 2.92±1.6 years of successful implant.

CONCLUSION

CRT devices can be implanted percutaneously even in the presence of substantial abnormalities of coronary venous anatomy. Alternative routes of venous access may be required. This article is protected by copyright. All rights reserved.

Patient Related Outcomes of Mechanical lead Extraction Techniques (PROMET) study: A comparison of two professions

BACKGROUND

With an increasing number of cardiac implantable electronic devices, there has been a paralleled increase in demand for transvenous lead extraction (TLE). Cardiac surgeons (CS) and cardiologists perform TLE; however, data comparing the two groups of operators is scarce.

OBJECTIVE

We compared the outcomes of TLE performed by cardiologists and CS from six European lead extraction units.

METHOD

Data was collected retrospectively of 2205 patients who had 3849 leads extracted (PROMET) between 2005-2018. Patient demographics and procedural outcomes were compared between the CS and cardiologist groups, using propensity score matching. A multivariate regression analysis was also performed for variables associated with 30-day mortality.

RESULTS

Cardiac surgeons performed the majority of extractions (59.8%), of leads with longer dwell times (90 [57-129 interquartile range (IQR)] vs 62 [31-102 IQR] months, CS vs cardiologists, p < 0.001) and with pre-dominantly non-infectious indications (57.4% vs 50.2%, CS vs cardiologists, p < 0.001). Cardiac surgeons achieved a higher complete success per lead than the cardiologists (98.1% vs 95.7%, respectively, p < 0.01), with a higher number of minor complications (5.51% vs 2.1%, p < 0.01) and similar number of major complications (0.47% vs 1.3%, p = 0.12). Thirty-day mortality was similarly low in the CS and cardiologist groups (1.76% vs 0.94%,p = 0.21). Unmatched data multivariate analysis revealed infection indication (OR 6.12 [1.9-20.3], p < 0.01), procedure duration (OR 1.01 [1.01-1.02], p < 0.01) and CS operator (OR 2.67, [1.12-6.37], p = 0.027) were associated with 30-day mortality.

CONCLUSION

Transvenous lead extraction by CS was performed with similar safety and higher efficacy compared to cardiologists in high and medium-volume lead extraction centres. This article is protected by copyright. All rights reserved.

Coronary Caverns: Spontaneous Recanalized Chronic Total Occlusion With Multiple Microchannels

Spontaneous chronic total occlusion recanalization is rare. It has scarcely been described previously and with minimal visual detail. Optical coherence tomography permitted comprehensive visualization of the microchannels in this case, seldom seen previously. With Thrombolysis in Myocardial Infarction 3 flow in the affected vessel via these patent channels, optimal medical therapy may be an appropriate strategy.

Arrhythmias in Chronic Kidney Disease

Arrhythmias cause disability and an increased risk of premature death in the general population but far more so in patients with renal failure. The association between the cardiac and renal systems is complex and derives in part from common causality of renal and myocardial injury from conditions including hypertension and diabetes. In many cases, there is a causal relationship, with renal dysfunction promoting arrhythmias and arrhythmias exacerbating renal dysfunction. In this review, the authors expand on the challenges faced by cardiologists in treating common and uncommon arrhythmias in patients with renal failure using pharmacological interventions, ablation and cardiac implantable device therapies. They explore the most important interactions between heart rhythm disorders and renal dysfunction while evaluating the ways in which the coexistence of renal dysfunction and cardiac arrhythmia influences the management of both.

Preventing esophageal complications from atrial fibrillation ablation: A review

Atrioesophageal fistula is a life-threatening complication of ablation treatment for atrial fibrillation. Methods to reduce the risk of esophageal injury have evolved over the last decade, and diagnosis of this complication remains difficult and therefore challenging to treat in a timely manner. Delayed diagnosis leads to treatment occurring in the context of a critically ill patient, contributing to the poor prognosis associated with this complication. The associated mortality risk can be as high as 70%. Recent important advances in preventative techniques are explored in this review.

Preventative techniques used in current clinical practice are discussed, which include high-power short-duration ablation, esophageal temperature probe monitoring, cryotherapy and laser balloon technologies, and use of proton pump inhibitors. A lack of randomized clinical evidence for the effectiveness of these practical methods are found. Alternative methods of esophageal protection has emerged in recent years, including mechanical deviation of the esophagus and esophageal temperature control (esophageal cooling). Although these are fairly recent methods, we discuss the available evidence to date. Mechanical deviation of the esophagus is due to undergo its first randomized study. Recent randomized study on esophageal cooling has shown promise of its effectiveness in preventing thermal injuries. Lastly, novel ablation technology that may be the future of esophageal protection, pulsed field ablation, is discussed.

The findings of this review suggest that more robust clinical evidence for esophageal protection methods is warranted to improve the safety of atrial fibrillation ablation.

COVID-19 opens the door for right iliac fossa pain treatment pathway

INTRODUCTION

The COVID-19 pandemic has increased the risks of surgery and management of common surgical conditions has changed, with greater reliance on imaging and conservative management. The negative appendectomy rate (NAR) in the UK has previously remained high. The aim of this study was to quantify pandemic-related changes in the management of patients with suspected appendicitis, including the NAR.

METHODS

A retrospective study was performed at a single high volume centre of consecutive patients aged over five years presenting to general surgery with right iliac fossa pain in two study periods: for two months before lockdown and for four months after lockdown. Pregnant patients and those with previous appendectomy, including right colonic resection, were excluded. Demographic, clinical, imaging and histological data were captured, and risk scores were calculated, stratifying patients into higher and lower risk groups. Data were analysed by age, sex and risk subgroups.

RESULTS

The mean number of daily referrals with right iliac fossa pain or suspected appendicitis reduced significantly between the study periods, from 2.92 before lockdown to 2.07 after lockdown (p<0.001). Preoperative computed tomography (CT) rates increased significantly from 22.9% to 37.2% (p=0.002). The NAR did not change significantly between study periods (25.5% prior to lockdown, 11.1% following lockdown, p=0.159). Twelve (75%) out of sixteen negative appendectomies were observed in higher risk patients aged 16-45 years who did not undergo preoperative CT. The NAR in patients undergoing CT was 0%.

CONCLUSIONS

Greater use of preoperative CT should be considered in risk stratified patients in order to reduce the NAR.

Persistent left superior vena cava transvenous lead extraction: A European experience

BACKGROUND

Transvenous lead extraction (TLE) is rising in parallel to cardiac implantable electronic device implantations. Persistent left side superior vena cava (PLSVC) is a relatively common anatomical variant in the healthy population; TLE in patients with a PLSVC is rare.

METHOD

Data were collated from 6 European TLE institutes of 10 patients who had undergone lead extraction with a PLSVC. Patient demographics, procedural challenges and outcomes were reported.

RESULTS

Ten patients aged 73.4 ± 7.8 years (60% male) underwent TLE of 20 leads (3 left ventricle, 10 right ventricle, 7 right atrium) with dwell time of 82.95 ± 39.1 months. Of the 10 cases, 4 had an infection indication and 5 were biventricular system extractions; 25% of the extracted leads were defibrillator leads. The majority of the procedures were completed in the cardiac catheterization suite (80%) under general anaesthesia (60%) by cardiologists (80%) using a rotational powered sheath (65%). The Tandem approach was used successfully in 3 cases. Complete procedural success was obtained in 100% of cases in the absence of complications within 127.4 ± 74.7 min. There was no 30-day mortality.

CONCLUSION

TLE in PLSVC is feasible albeit rare. Standard extraction techniques in experienced hands are associated with favorable outcomes; the Tandem procedure may be an additional technique to improve the safety and efficacy of TLE in PLSVC.

Randomized comparison of oesophageal protection with a temperature control device: results of the IMPACT study

Aims 

Thermal injury to the oesophagus is an important cause of life-threatening complication after ablation for atrial fibrillation (AF). Thermal protection of the oesophageal lumen by infusing cold liquid reduces thermal injury to a limited extent. We tested the ability of a more powerful method of oesophageal temperature control to reduce the incidence of thermal injury.

Methods and results 

A single-centre, prospective, double-blinded randomized trial was used to investigate the ability of the ensoETM device to protect the oesophagus from thermal injury. This device was compared in a 1:1 randomization with a control group of standard practice utilizing a single-point temperature probe. In the protected group, the device maintained the luminal temperature at 4°C during radiofrequency (RF) ablation for AF under general anaesthesia. Endoscopic examination was performed at 7 days post-ablation and oesophageal injury was scored. The patient and the endoscopist were blinded to the randomization. We recruited 188 patients, of whom 120 underwent endoscopy. Thermal injury to the mucosa was significantly more common in the control group than in those receiving oesophageal protection (12/60 vs. 2/60; P = 0.008), with a trend toward reduction in gastroparesis (6/60 vs. 2/60, P = 0.27). There was no difference between groups in the duration of RF or in the force applied (P value range= 0.2–0.9). Procedure duration and fluoroscopy duration were similar (P = 0.97, P = 0.91, respectively).

Conclusion 

Thermal protection of the oesophagus significantly reduces ablation-related thermal injury compared with standard care. This method of oesophageal protection is safe and does not compromise the efficacy or efficiency of the ablation procedure.

Prevalence of bradyarrhythmias needing pacing in COVID-19

Background

The Sars‐Cov‐2 infection is a multisystem illness that can affect the cardiovascular system. Tachyarrhythmias have been reported but the prevalence of bradyarrhythmia is unclear. Cases have been described of transient high‐degree atrioventricular (AV) block in COVID‐19 that were managed conservatively.

Method

A database of all patients requiring temporary or permanent pacing in two linked cardiac centers was used to compare the number of procedures required during the first year of the pandemic compared to the corresponding period a year earlier. The database was cross‐referenced with a database of all patients testing positive for Sars‐Cov‐2 infection in both institutions to identify patients who required temporary or permanent pacing during COVID‐19.

Results

The number of novel pacemaker implants was lower during the COVID‐19 pandemic than the same period the previous year (540 vs. 629, respectively), with a similar proportion of high‐degree AV block (38.3% vs. 33.2%, respectively, p = .069). Four patients with the Sars‐Cov‐2 infection had a pacemaker implanted for high‐degree AV block, two for sinus node dysfunction. Of this cohort of six patients, two succumbed to the COVID‐19 illness and one from non‐COVID sepsis. Device interrogation demonstrated a sustained pacing requirement in all cases.

Conclusion

High‐degree AV block remained unaltered in prevalence during the COVID‐19 pandemic. There was no evidence of transient high‐degree AV block in patients with the Sars‐Cov‐2 infection. Our experience suggests that all clinically significant bradyarrhythmia should be treated by pacing according to usual protocols regardless of the COVID status.

Transvenous lead extraction: The influence of age on patient outcomes in the PROMET study cohort

BACKGROUND

Cardiac implantable electronic device (CIED) therapy contributes to an improvement in morbidity and mortality across all patient demographics. Patient age is a recognized risk factor for unfavorable outcomes in invasive procedures. This is the largest series of non-laser transvenous lead extraction (TLE) evaluating the association between patient age and procedure outcomes.

METHODS

Data of 2205 (3849 leads) patients was collected retrospectively from six European TLE centers between January 2005-December 2018 in the PROMET study. Of these, 153 patients with 319 leads were excluded for incomplete data. A comparison of outcomes was performed between the age groups young [< 50 years], young intermediate [50-69 years], older intermediate [70-79 years], and octogenarian [≥80 years].

RESULTS

Infection was most common indication for TLE in the octogenarian cohort, less common in the younger population (60.1% vs. 33.2%, respectively, p < .01). High-voltage leads were extracted most frequently from young patients, less frequently from octogenarians (31.6% vs. 10%, p < .001), while the opposite was evident for pacemaker leads (p < .001). Rotational sheath use was equally prevalent across all patient groups (p = .79). Minor and major complications across all the age groups were statistically similar, as was procedural success; the 30-day mortality was most significant in the octogenarian and least in the young patients (4.9% vs. 0.4%, p = .005). Propensity matching multivariate analysis found systemic infection, lead dwell time, and patient age (p = .013, OR 1.064 [1.013-1.116]) increased risk of 30-day mortality.

CONCLUSION

TLE is safe and effective across all age groups. 30-day mortality risk is significantly higher in the older patients.

PROMET: The effect of operator profession on non-laser transvenous lead extraction

Funding Acknowledgements

Type of funding sources: None.

OnBehalf

PROMET group

Background

As implantation of cardiac implantable devices (CIED) rises globally, there is a paralleled need for extraction of these devices. Indications for transvenous lead extraction (TLE) is expanding, fuelling demand. This lifesaving procedure is performed by cardiologists and cardiac surgeons (CS). Cardiologists are familiar with transvenous methods whilst cardiac surgeons possess the skillset to address the significant complications associated with this procedure.

We compared non-laser TLE outcomes performed by cardiologists and cardiac surgeons from six high-volume extraction centres across Europe.

Methods

Data was collected retrospectively from six major European TLE centres of 2205 patients and 3849 leads (PROMET). Propensity 1:1 score matching (PSM) was performed to account for confounding variables. PSM model with variables: lead dwell time, infection indication, biventricular system and defibrillator device, was best matched. This dataset was analysed to compare outcomes of TLE performed by the cardiologists and CS. Predictors of 30-day mortality and complications were identified using a multivariate regression analysis.

Results

Patients treated by CS and cardiologists were similar in age (64.7 vs 66.7 years, p = NS) and equally male (70.3% vs 72.3%, p = 0.39) with a parallel infectious indication (51.7% vs 47.6%, p = 0.1). Surgeons achieved a significantly higher proportion of clinical success than cardiologists (98.9% vs 96.4%, p = 0.001) and complete lead extraction (98% vs 95.9%, p &lt; 0.01) with a higher rate of minor complications (4.1% vs 2.2%, p = 0.024); major complications were similar (0.9% vs 1.2%, respectively, p = 0.46) as was 30-day mortality (3.2% vs 2%, respectively, p = 0.28). Multivariate regression analysis revealed systemic infection (p &lt; 0.001, OR 7.2 [CI 2.3-20.1]) and defibrillator system extraction (p = 0.025, OR 3.4 [CI 1.2-10.2]) increased the odds of 30-day mortality, whilst Evolution™ sheath use reduced the odds (p = 0.025, OR 0.34 [CI 0.13-0.88]); lead dwell time (p = 0.02, OR 1.005 [1-1.009] and Evolution™ sheath use (p = 0.023, OR 2.15[1.1-4.15]) increased the odds of complications.

Conclusion

Cardiac surgeons and cardiologists achieved a high rate of TLE procedural success and with a similar safety profile, replicating standards seen across Europe.

PROMET: the effect of age on patient outcomes in non-laser transvenous lead extraction

Funding Acknowledgements

Type of funding sources: None.

OnBehalf

PROMET group

Background

Cardiac implantable electronic devices (CIEDs) improve morbidity and mortality. This has fuelled an upsurge in implantation of these devices across all patient cohorts, simultaneously increasing the need for transvenous lead extractions (TLE). As the global population expands and life-expectancy extends, TLE will play a significant role in CIED management. Advancing patient age is a recognised risk factor for poor outcomes however the association between patient age and TLE outcomes remains unclear. 

We sought to evaluate the relationship between patient age and non-laser TLE outcomes.

Method

Data of 2205 patients (3849 leads) was collected retrospectively from six high-volume TLE institutes across Europe (PROMET) between January 2005-December 2018. Propensity 1:1 score matching was performed to limit the effects of confounding variables, pairing 353 patients in the &gt;80 years of age category with 353 patients in &lt;80 years of age group. Procedural outcomes were compared between the two age groups and multivariate regression analysis was used for predictors of 30-day mortality.

Results

In the &lt;80 and &gt;80 years-of-age cohorts, there was a similar proportion of male patients (65.3% vs 67.9%, p = 0.47) treated under general anaesthesia (96.5% vs 93.4%, p = 0.078) for a pre-dominant infectious indication (56.7% vs 60.3%, p = 0.52) but with a higher requirement of the EvolutionTM sheath in the octogenarians (39.4% vs 48.4%, p = 0.015). A similar clinical success per lead was achieved between the two age groups (96.6% vs 98%, &lt;80 vs &gt;80 years, p = 0.245) as was complete lead extraction (95.5% vs 96.6%, &lt;80 vs &gt;80 years, p = 0.44) with a comparable minor complication rate (2.3% vs 3.1%, &lt;80 vs &gt;80 years, p = 0.29) and major complications (1.1% vs 1.4%, &lt;80 vs &gt;80 years, p = 0.74). Thirty-day mortality was higher in the octogenarian cohort than the &lt;80-year-olds without reaching statistical significance (5.4% vs 2.6%, p = 0.08); peri-procedural mortality was similar in both age groups (0.3% vs 0.6%, respectively, p = 0.56). Multivariate regression analysis revealed age (p = 0.013, OR 1.06 [1.01-1.12]), systemic infection (p = 0.026, OR 3.4 [1.16-10.35]) and lead dwell time (p = 0.007, OR 1.01 [1.003-1.017]) increased the odds of 30-day mortality.

Conclusion

Transvenous lead extraction is similar in efficacy and safety across all age groups. Thirty-day mortality is higher in the advanced age group, signifying the importance of post-procedural management in this cohort.

Transvenous lead revision for cardiac perforation: a single centre experience

Funding Acknowledgements

Type of funding sources: None.

Background

Cardiac perforation is an uncommon but life-threatening complication of cardiac implantable electronic device (CIED) implantation. Management strategy commonly relies on diagnostic Computed Tomography (CT) imaging and cardiac surgery. Emerging evidence has indicated a diversion from this approach. Transvenous culprit lead revision has been shown to be safe and efficacious in limited series.

We sought to evaluate the outcomes of transvenous lead revision in patients with cardiac perforation.

Method

Data was collected retrospectively of patients admitted to a single tertiary centre with CIED-related cardiac perforation between December 2013 – October 2019. Transvenous lead revision was performed as standard with cardiac surgery on standby. Patient demographics, use of CT imaging, method of removal and 30-day outcomes were recorded.

Results

Of the 46 recorded CIED-related cardiac perforations, the majority occurred in female patients (63%) and hypertensives (61%), whilst a proportion had cancer (20%) and ischaemic heart disease (30%). The culprit in most cases was a standard pacing lead (92%) of an active fixation (98%) in the right ventricle (80%) positioned at the ventricular apex (65%). The median time to presentation from implant was 14 days [IQR 4-50 days] with chest pain (44%); abnormal pacing indices was highly prevalent (95%) whilst a pericardial effusion was noted in the majority of cases (57%). CT scanning was performed in 19 cases (41%) for various indications but deemed essential in only 4, all of which had non-diagnostic pacing indices and imaging. Chest X-ray (CXR) found clear perforation, lead displacement or pleural effusion in 74% of cases, whilst an echocardiogram found these in 64% of cases. The culprit lead was replaced in the majority of cases (87%) under local anaesthesia (76%) with surgical backup. The median hospital stay was 7 days [IQR 3-10 days] with zero procedural and 30-day mortality.

Conclusion

Transvenous lead revision for CIED-related cardiac perforation is safe and efficacious. CT modality for diagnostic purposes is useful in providing incremental value in a minority of cases; patients with non-diagnostic pacing parameters and non-CT imaging benefit most from this.

A registry review of 2532 catheter ablations for atrial fibrillation using active thermal protection

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Dr Leung has received research support from Attune Medical (Chicago, IL). Dr Gallagher has received research funding from Attune Medical (Chicago, IL).

Background

  Thermal injury to the oesophagus causes a spectrum of adverse effects after ablation for atrial fibrillation (AF); at the most severe end, atrio-oesophageal fistula carries a high mortality rate. Controlled active thermal protection in the oesophagus during ablation is the most promising method of oesophageal protection. Randomized evidence from the IMPACT trial (NCT03819946) showed an 83.4% reduction in endoscopically detected oesophageal lesions compared to standard care when an oesophageal temperature control device was used to control the local temperature. The IMPACT patients who were randomized to the use of the device had no adverse event related to its use.  Real world registry data on applications of this device have not previously been available. 

Purpose

To determine the safety of an oesophageal temperature control device by review of real-world registry data on its clinical use and any reported device-related adverse events.

Methods

  We reviewed the following databases for any reported oesophageal temperature control device-related complications: The United States Food and Drug Administration (FDA) Manufacturer and User Facility Device Experience (MAUDE), FDA Medical and Radiation Emitting Device Recalls, the Medicines and Healthcare products Regulatory Agency (MHRA) Medical Device Alerts and SwissMedic records of Field Safety Corrective Actions (FSCA). An internal registry (post-marketing follow up) database maintained by the manufacturer of the device was used to quantify the number used for each indication.  Reported events were reviewed and catalogued for description and identification of any events related to its use in the cardiac electrophysiology lab. The IMPACT study patients were reviewed for any device-related events.

Results

  Of the 13, 284 oesophageal temperature control devices used, 2532 were recorded as having been used for the purpose of oesophageal protection during catheter ablation for AF.  A total of 5 events associated with the device were identified, all from the MAUDE database.  Three were from 2017, one from 2018, and one from 2019.  All involved its use in critical care or trauma patients and were related to user error or contraindicated patient selection; none resulted in serious harm to the patient. No adverse events occurred related to its use in the cardiac electrophysiology lab. No case of clinically significant oesophageal injury was reported in a patient who had been protected by the oesophageal temperature control device.

Conclusions

Real world registry data has shown no adverse events reported to date in over 2500 uses of an oesophageal temperature control device in the cardiac electrophysiology lab, for the purpose of active thermal protection. This data supports the randomized trial evidence of its clinical effectiveness. Abstract Figure. Oesophageal active thermal protection

Prolonged QT predicts prognosis in COVID-19

Background

Coronavirus disease‐2019 (COVID‐19) causes severe illness and multi‐organ dysfunction. An abnormal electrocardiogram is associated with poor outcome, and QT prolongation during the illness has been linked to pharmacological effects. This study sought to investigate the effects of the COVID‐19 illness on the corrected QT interval (QTc).

Method

For 293 consecutive patients admitted to our hospital via the emergency department for COVID‐19 between 01/03/20 ‐18/05/20, demographic data, laboratory findings, admission electrocardiograph and clinical observations were compared in those who survived and those who died within 6 weeks. Hospital records were reviewed for prior electrocardiograms for comparison with those recorded on presentation with COVID‐19.

Results

Patients who died were older than survivors (82 vs 69.8 years, p < 0.001), more likely to have cancer (22.3% vs 13.1%, p = 0.034), dementia (25.6% vs 10.7%, p = 0.034) and ischemic heart disease (27.8% vs 10.7%, p < 0.001). Deceased patients exhibited higher levels of C‐reactive protein (244.6 mg/L vs 146.5 mg/L, p < 0.01), troponin (1982.4 ng/L vs 413.4 ng/L, p = 0.017), with a significantly longer QTc interval (461.1 ms vs 449.3 ms, p = 0.007). Pre‐COVID electrocardiograms were located for 172 patients; the QTc recorded on presentation with COVID‐19 was longer than the prior measurement in both groups, but was more prolonged in the deceased group (448.4 ms vs 472.9 ms, pre‐COVID vs COVID, p < 0.01). Multivariate Cox‐regression analysis revealed age, C‐reactive protein and prolonged QTc of >455 ms (males) and >465 ms (females) (p = 0.028, HR 1.49 [1.04‐2.13]), as predictors of mortality. QTc prolongation beyond these dichotomy limits was associated with increased mortality risk (p = 0.0027, HR 1.78 [1.2‐2.6]).

Conclusion

QTc prolongation occurs in COVID‐19 illness and is associated with poor outcome.

Percutaneous management of lead-related cardiac perforation with limited use of computed tomography and cardiac surgery

BACKGROUND

Cardiac implantable electronic device (CIED)-related perforation is uncommon but potentially lethal. Management typically includes the use of computed tomography (CT) scanning and often involves cardiac surgery.

METHODS

Patients presenting to a single referral centre with CIED-related cardiac perforation between 2013 and 2019 were identified. Demographics, diagnostic modalities, the method of lead revision, and 30-day complications were examined.

RESULTS

A total of 46 cases were identified; median time from implantation to diagnosis was 14 days (interquartile range = 4-50). Most were females (29/46, 63%), 9/46 (20%) had cancer, 18 patients (39%) used oral anticoagulants, and no patients had prior cardiac surgery. Active fixation was involved in 98% of cases; 9% involved an implantable cardioverter defibrillator lead. Thirty-seven leads perforated the right ventricle (apex: 24) and 9 punctured the right atrium (lateral wall: 5). Abnormal electrical parameters were noted in 95% of interrogated cases. Perforation was visualized in 41% and 6% of cases with chest X-ray (CXR) and transthoracic echocardiography, respectively. CXR revealed a perforation, gross lead displacement, or left-sided pleural effusion in 74% of cases. Pericardial effusion occurred in 26 patients (57%) of whom 11 (24%) developed tamponade, successfully drained percutaneously. Pre-extraction CT scan was performed in 19 patients but was essential in four cases. Transvenous lead revision (TLR) was successfully performed in all cases with original leads repositioned in six patients, without recourse to surgery. Thirty-day mortality and complications were low (0% and 26%, respectively).

CONCLUSION

CT scanning provides incremental diagnostic value in a minority of CIED-related perforations. TLR is a safe and effective strategy.

Innovative Cardiac Resynchronization: Deployable Lead as an Anchor to Facilitate Guidewire Advancement

An acutely angulated coronary sinus ostium coupled with a dilated right atrium presents technical challenges for cardiac resynchronization therapy (CRT) implantation. Innovative use of a deployable left ventricle lead as an anchor to support guidewire navigation within the cardiac venous system permits optimal CRT deployment. (Level of Difficulty: Advanced.)

Multi-lead cephalic venous access and long-term performance of high-voltage leads

BACKGROUND

Cardiac resynchronization therapy-defibrillator (CRT-D) implantation via the cephalic vein is feasible and safe. Recent evidence has suggested a higher implantable cardioverter-defibrillator (ICD) lead failure in multi-lead defibrillator therapy via the cephalic route. We evaluated the relationship between CRT-D implantation via the cephalic and ICD lead failure.

METHODS

Data was collected from three CRT-D implanting centers between October 2008 and September 2017. In total 633 patients were included. Patient and lead characteristics with ICD lead failure were recorded. Comparison of "cephalic" (ICD lead via cephalic) versus "non-cephalic" (ICD lead via non-cephalic route) cohorts was performed. Kaplan-Meier survival and a Cox-regression analysis were applied to assess variables associated with lead failure.

RESULTS

The cephalic and non-cephalic cohorts were equally male (81.9% vs. 78%; p = .26), similar in age (69.7 ± 11.5 vs. 68.7 ± 11.9; p = .33) and body mass index (BMI) (27.7 ± 5.1 vs. 27.1 ± 5.7; p = .33). Most ICD leads were implanted via the cephalic vein (73.5%) and patients had a mean of 2.9 ± 0.28 leads implanted via this route. The rate of ICD lead failure was low and statistically similar between both groups (0.36%/year vs. 0.13%/year; p = .12). Female gender was more common in the lead failure cohort than non-failure (55.6% vs. 17.9%, respectively; p = .004) as was hypertension (88.9% vs. 54.2%, respectively, p = .038). On multivariate Cox-regression, female sex (p = .008; HR, 7.12 [1.7-30.2]), and BMI (p = .047; HR, 1.12 [1.001-1.24]) were significantly associated with ICD lead failure.

CONCLUSION

CRT-D implantation via the cephalic route is not significantly associated with premature ICD lead failure. Female gender and BMI are predictors of lead failure.