Rapid Roll Out of a Pacemaker Home Monitoring Programme: A Patient Perspective.

OBJECTIVE: To assess the safety, efficacy, and patient acceptability of a pacemaker home monitoring (HM) service. METHODS: All patients receiving a new Biotronik (Biotronik, Berlin, Germany) pacemaker between March 2020 and February 2021 were contacted for participation. Participants were surveyed on their experience of pacemaker HM. HM alerts and remote wound monitoring rates were also assessed. RESULTS: Of the patients contacted, 77% responded, with a mean age of 80.6±9.9 years. Of these, 95.8% agreed that the home monitoring (HM) has been beneficial. Two thirds preferred HM to face-to-face follow-up and two thirds felt safe with HM. Three themes were identified from the comments: reassurance, technology and data security. Forty-one percent (41%) of respondents would like more reassurance that their HM is working, 18% mentioned technology with mixed responses, and 4.7% cited cybersecurity or the use of their personal data as a concern. The average one-way patient journey saved was 24.3±16.7 km (15.1±10.4 miles). One in three HM alerts required action but only 3.4% were urgent. Remote wound review was successful in 59%. CONCLUSIONS: The majority of patients prefer HM and almost all think it has been beneficial. It saves significant travel time and provides actionable alerts. The patient experience could be improved by reassuring patients that their device is being monitored.

The Effect of Atrial Fibrillation Ablation Techniques on P Wave Duration and P Wave Dispersion.

BACKGROUND: A reduction in surface electrocardiogram (ECG) P wave duration and dispersion is associated with improved outcomes in atrial fibrillation ablation. We investigated the effects of different ablation strategies on P wave duration and dispersion, hypothesising that extensive left atrial (LA) ablation with left atrial posterior wall isolation would give a greater reduction in P wave duration than more limited ablation techniques. METHODS: A retrospective analysis of ECGs from patients who have undergone atrial fibrillation (AF) ablation was performed and pre-procedural sinus rhythm ECGs were compared with the post procedure ECGs. Maximal P wave duration was measured in leads I or II, minimum P wave duration in any lead and values were calculated for P wave duration and dispersion. Left atrial dimensions and medications at the time of ECG were documented. Ablation strategies compared were; pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (PAF) and the persistent AF (PsAF) ablation strategies of pulmonary vein isolation plus additional linear lesions (Lines), left atrial posterior wall isolation via catheter (PWI) and left atrial posterior wall isolation via staged surgical and catheter ablation (Hybrid). RESULTS: Sixty-nine patients' ECGs were analysed: 19 PVI, 21 Lines, 14 PWI, 15 Hybrid. Little correlation was seen between pre-procedure left atrial size and P wave duration (r=0.24) but LA size and P wave duration was larger in PsAF patients. A significant difference was seen in P wave reduction driven by Hybrid AF ablation (p<0.005) and Lines (<0.02). There was no difference amongst P wave dispersion between groups but the largest reduction was seen in the Hybrid ablation group. CONCLUSIONS: P wave duration increased with duration of continuous atrial fibrillation. Hybrid AF ablation significantly reduced P wave duration and dispersion compared to other ablation strategies including posterior wall isolation via catheter despite this being the same lesion set.

A novel approach to mapping the atrial ganglionated plexus network by generating a distribution probability atlas.

INTRODUCTION: The ganglionated plexuses (GPs) of the intrinsic cardiac autonomic system are implicated in arrhythmogenesis. GP localization by stimulation of the epicardial fat pads to produce atrioventricular dissociating (AVD) effects is well described. We determined the anatomical distribution of the left atrial GPs that influence atrioventricular (AV) dissociation. METHODS AND RESULTS: High frequency stimulation was delivered through a Smart-Touch catheter in the left atrium of patients undergoing atrial fibrillation (AF) ablation. Three dimensional locations of points tested throughout the entire chamber were recorded on the CARTO™ system. Impact on the AV conduction was categorized as ventricular asystole, bradycardia, or no effect. CARTO maps were exported, registered, and transformed onto a reference left atrial geometry using a custom software, enabling data from multiple patients to be overlaid. In 28 patients, 2108 locations were tested and 283 sites (13%) demonstrated (AVD-GP) effects. There were 10 AVD-GPs (interquartile range, 11.5) per patient. Eighty percent (226) produced asystole and 20% (57) showed bradycardia. The distribution of the two groups was very similar. Highest probability of AVD-GPs (>20%) was identified in: inferoseptal portion (41%) and right inferior pulmonary vein base (30%) of the posterior wall, right superior pulmonary vein antrum (31%). CONCLUSION: It is feasible to map the entire left atrium for AVD-GPs before AF ablation. Aggregated data from multiple patients, producing a distribution probability atlas of AVD-GPs, identified three regions with a higher likelihood for finding AVD-GPs and these matched the histological descriptions. This approach could be used to better characterize the autonomic network.

Thrombo-embolic events in left ventricular endocardial pacing: long-term outcomes from a multicentre UK registry.

Aims: Endocardial left ventricular (LV) pacing is a viable alternative in patients with failed coronary sinus (CS) lead implantation. However, long-term thrombo-embolic risk remains unknown. Much of the data have come from a small number of centres. We examined the safety and efficacy of endocardial LV pacing to determine the long-term thrombo-embolic risk. Methods and results: Registries from four UK centres were combined to include 68 patients with endocardial leads with a mean follow-up of 20 months. These were compared to a matched 1:2 control group with conventional CS leads. Medical records were reviewed, and patients contacted for follow-up. Ischaemic stroke occurred in four patients (6%) in the endocardial arm providing an annual event rate (AER) of 3.6% over a 20 month follow-up; compared to 9 patients (6.6%) amongst controls with an AER of 3.4% over a 23-month follow-up. Regression analyses showed a significant association between sub-therapeutic international normalized ratio and stroke (P = 0.0001) in the endocardial arm. There was no association between lead material and mode of delivery (transatrial/transventricular) and stroke. Mortality rate was 12 and 15 per 100 patient years in the endocardial and control arm respectively with end-stage heart failure being the commonest cause. Conclusion: Endocardial LV lead in heart failure patients has a good success rate at 1.6 year follow-up. However, it is associated with a thrombo-embolic risk (which is not different from conventional CS leads) attributable to sub-therapeutic anticoagulation. Randomized control trials and studies on non-vitamin K antagonist oral anticoagulants are required to ascertain the potential of widespread clinical application of this therapeutic modality.

The use of an esophageal catheter to check the results of left atrial posterior wall isolation in the treatment of atrial fibrillation.

BACKGROUND: Left atrial posterior wall isolation (LAPWI) via catheter, surgical, and hybrid techniques is a promising treatment for persistent atrial fibrillation (PersAF). We investigated whether confirmation of LAPWI can be achieved using an esophageal pacing and recording electrode. METHODS: Patients undergoing PersAF ablation with the intention to achieve LAPWI were enrolled. Two approaches to LAPWI were tested: (1) ablation using endocardial catheter ablation only, and (2) "Staged Hybrid" ablation with thoracoscopic epicardial ablation, followed by endocardial left atrial electrophysiological study and catheter ablation where necessary. Patients enrolled in the study all required further catheter ablation to achieve LAPWI in this group. In both the groups, esophageal recording and esophageal pacing was performed at the start of mapping and electrophysiological study and compared with endocardial electrophysiological findings. This was repeated at the end of the procedure. RESULTS: Twenty patients (16 M, four F) were studied. Endocardial electrophysiological study showed that in none of the cases was the posterior left atrial wall electrically isolated at the start of the study. One patient with Barrett's esophagus failed to sense or pace from the esophagus at any point in the study. In the remaining 19/19, esophageal pacing captured the atrial rhythm at the start of the procedure. LAPWI was then achieved in 17/19 using endocardial catheter ablation; retesting at this point showed sensing and capture of the atrium from the esophagus was abolished. In the remainder sensing and capture persisted. CONCLUSIONS: Esophageal pacing can be used to confirm or refute electrical isolation of the left atrial posterior wall.

Cardiac troponin levels following implantable cardioverter defibrillation implantation and testing.

AIMS: Previous studies have reported the defibrillation testing during implantable cardioverter defibrillator (ICD) implantation is associated with elevated cardiac biomarkers and ST-segment electrocardiogram (ECG) changes suggesting that shocks during testing may cause harm. However, the effects of testing have not been isolated from the implant procedure itself, where lead deployment may cause myocardial damage. This prospective study examined high sensitivity troponin T (hs-TnT) levels and ECG changes during ICD implanting alone, ICD implantation with testing and device testing as a stand-alone procedure. METHODS AND RESULTS: We examined hs-TnT at baseline, and 6-8 h post procedure and 12 lead ECG at baseline, and 30 s, 5 min, and 10 min post right ventricle lead deployment and post defibrillation. There was no significant change in hs-TnT levels in a group of patients (n = 11) undergoing defibrillation testing alone, while hs-TnT was significantly elevated in patients undergoing implantation alone (n = 13, median increase 96%, P = 0.005) and in patients undergoing implantation and testing (n = 13, median increase 161%, P = 0.005). There was a significant correlation between the number of lead deployments and the percentage change in hs-TnT (r = -0.51, P = 0.01), but no correlation between either the number of shocks (r = 0.26, P = 0.25) or the total delivered energy (r = 0.24, P = 0.30) and percentage change in hs-TnT. CONCLUSION: Implantation of ICD leads was associated with release of troponin, but we did not observe any evidence that ICD shocks alone cause myocardial injury.

Wire Externalisation for Left Ventricular Lead Placement in Cardiac Resynchronisation Therapy: A Step-by-step Guide.

BACKGROUND: Left ventricular (LV) lead implantation for CRT can be challenging. We describe the technique of wire externalisation to enable posterolateral (PL) LV lead placement and give case examples to illustrate its use. METHODS: The technique includes: The externalised guidewire provides excellent support for antegrade or retrograde advancement of the LV lead. RESULTS: Wire externalisation has been used to overcome PL branch tortuosity, persistent left SVC or acute angulation of the CS ostium. Antegrade delivery or retrograde delivery is possible but there may be an additional need for balloon angioplasty to facilitate lead advancement. There have been no complications at implant or 30-day follow-up. CONCLUSIONS: The wire externalisation technique can facilitate optimal LV lead placement in difficult CRT cases.

Cardiac tamponade as a presentation of primary adrenal insufficiency.

Cardiac tamponade is an important and severe consequence of pericardial effusion. Patients with haemodynamically significant pericardial effusions present with signs and symptoms relating to the degree of their impaired cardiac function. Although autoimmune disease is a recognised cause of pericardial effusion, cardiac tamponade as a clinical presentation of primary adrenal insufficiency (PAI) is infrequently reported. We present a case of a woman, in her early 50s, who was admitted to the coronary care unit with cardiac tamponade caused by an acute adrenal crisis from unrecognised PAI. We hope to raise clinicians' awareness of PAI as a rare but important cause of cardiac tamponade.

The effect of a standardised protocol for CIED insertion on complications and infection rates in a DGH.

Cardiac implantable electronic device (CIED)-related complications and infections typically lead to prolonged hospital stays and, very occasionally, death. A new CIED insertion protocol was implemented in a district general hospital. The primary objective of this study was to determine whether a significant reduction in complication and infection rates occurred after implementation of the new protocol. Medical records were reviewed for patients who had a CIED inserted in the two years pre- and post-protocol implementation, and any complications were identified in a one-year follow-up period. An increase in the complexity of the devices implanted after introduction of the protocol was observed. The number of complications was significantly reduced from 6.86% to 3.95% (p<0.0001). In the two years prior to protocol implementation, 14 of 871 (1.6%) patients suffered a CIED-related infection. In contrast, four of 683 (0.44%) patients suffered a CIEDrelated infection in the two years postimplementation. This was not statistically significant (p=0.093). In conclusion, implementing a standardised protocol for CIED insertion significantly reduced the rate of complications, and also reduced the rate of infection, but this was not statistically significant.

Isoprenaline and quinidine to calm Brugada VF storm.

A 3-year-old man with an implanted cardioverter-defibrillator (ICD) for type 2 Brugada syndrome was admitted to coronary care unit with ventricular fibrillation electrical storm and consequent appropriate recurrent ICD shocks. The rhythm did not settle with conventional antiarrhythmics such as ß-blockers and amiodarone. An isoprenaline infusion was set up with immediate stabilisation of rhythm. After a period of monitoring, the infusion was stopped and oral quinidine was started. He has remained free of problems for 1 year. This case-report summarises these novel treatments for electrical storm in Brugada syndrome and the mechanism behind them.