Randomized Trial of Stand-Alone Use of the Antimicrobial Envelope in High-Risk Cardiac Device Patients.

BACKGROUND: Cardiac implantable electronic device (CIED) infection has a high mortality. Previous investigations showed reduced postoperative infections using skin preparation with chlorhexidine, preoperative intravenous antibiotics, and a TYRX-a antibacterial envelope. The additional benefit of antibiotic pocket wash and postoperative antibiotics has not been systematically studied. METHODS: The ENVELOPE trial (A Randomized trial of Stand-Alone Use of the Antimicrobial Envelope in High-Risk Cardiac Device Patients) was a prospective, multicenter, randomized, controlled trial enrolling patients undergoing CIED procedures with ≥2 risk factors for infection. The control arm received standard chlorhexidine skin preparation, intravenous antibiotics, and the TYRX-a antibiotic envelope. The study arm received pocket wash (500 mL antibiotic solution) and postoperative antibiotics for 3 days along with the prophylactic control measures. The primary end point was CIED infection and system removal at 6 months. RESULTS: One thousand ten subjects (505 per arm) were enrolled and randomized. Patients were seen in person for a wound check with digital photo 2 weeks postimplant and at 3 and 6 months. CIED infection rate was low in both groups (1.0% control arm and 1.2% study arm, P=0.74). In the 11 subjects with infection and system removal, the time to study end point was 107±92 days with a PADIT (Prevention of Arrhythmia Device Infection Trial) score of 7.4 and a 64% 1-year mortality. Prior history of CIED infection independently predicted CIED system removal at 6 months in all subjects (odds ratio, 9.77, P=0.004). Of 11 infections requiring system removal, 5 were in the setting of pocket hematoma. CONCLUSIONS: The use of antibiotic pocket irrigation and postoperative oral antibiotics provides no additional benefit to the prophylactic measures of chlorhexidine skin preparation, preoperative intravenous antibiotics, and an antibiotic envelope in reducing CIED infection. Postoperative hematoma is a major risk factor for infection, driven by the use of antiplatelet and anticoagulant medications. The strongest predictor of CIED removal at 6 months, regardless of intervention, was prior CIED infection. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02809131.

Ablation of typical atrial flutter using mini electrode measurements for maximum voltage-guided ablation: A randomized, controlled trial.

BACKGROUND: Novel ablation catheters with mini electrode (ME) sensing have become available but their utility is unclear. We investigated whether ablation of the cavotricuspid isthmus (CTI) for atrial flutter (AFL) would be improved using ME signals. METHODS: Sixty-one patients (76% male, 63 ± 10 years) with CTI-dependent AFL underwent ablation using a maximum voltage-guided approach, randomized to either standard 8 mm non-irrigated catheter with bipolar signals or IntellaTip MiFi catheter using ME signals alone. RESULTS: Acute bidirectional block was achieved in 97%. Mean follow-up was 16.7 ± 10 months. The median number of ablation lesions was 13 in both groups (range 3-62 vs. 1-43, p = .85). No significant differences were observed in AFL recurrences (17% vs. 11%, p = .7), median procedure durations (97 min [interquartile range (IQR), 71-121] vs. 87 min [IQR, 72-107], p = .55) or fluoroscopy times (31 min [IQR, 21-52] vs. 38 min [IQR, 25-70], p = .56). Amplitudes of ME signals were on average 160% greater than blinded bipolar signals. In 23.7% of lesions where bipolar signals were difficult to interpret, 13.6% showed a clear ME signal. CONCLUSIONS: There was no difference in the effectiveness of CTI ablation guided by ME signals, compared with using bipolar signals from a standard 8 mm ablation catheter. While ME signal amplitudes were larger and sometimes present when the bipolar signal was unclear, this did not improve procedural characteristics or outcomes. The results suggest future research should focus on lesion integrity rather than signal sensing.

Position Statement on the Management of Cardiac Electrophysiology and Cardiac Implantable Electronic Devices in Australia During the COVID-19 Pandemic: A Living Document.

The COVID-19 pandemic poses a significant stress on health resources in Australia. The Heart Rhythm Council of the Cardiac Society of Australia and New Zealand aims to provide a framework for efficient resource utilisation balanced with competing risks when appropriately treating patients with cardiac arrhythmias. This document provides practical recommendations for the electrophysiology (EP) and cardiac implantable electronic devices (CIED) services in Australia. The document will be updated regularly as new evidence and knowledge is gained with time.

Miniaturized implantable cardiac monitor with a long sensing vector (BIOMONITOR III): Insertion procedure assessment, sensing performance, and home monitoring transmission success.

BACKGROUND: Implantable Cardiac Monitors (ICMs) are used for long-term monitoring of arrhythmias. BIOMONITOR III is a novel ICM with a miniaturized profile, long sensing vector due to a flexible antenna, simplified implantation with a dedicated insertion tool for pocket formation and ICM placement in a single step, and daily automatic Home Monitoring (HM) function. METHODS: In 47 patients undergoing BIOMONITOR III insertion for any ICM indication, 16 investigators at 10 Australian sites assessed handling characteristics of the insertion tool, R-wave amplitudes, noise burden, P-wave visibility, and HM transmission success. Patients were followed for 1 month. RESULTS: All 47 attempted insertions were successful. Median time from skin incision to removal of the insertion tool after ICM insertion was 39 s (IQR 19-65) and to wound closure and cleaning was 4.7 min (IQR 3.5-7.8). All aspects of the insertion tool were rated as "good" or "excellent" in ≥97.9% and "fair" in ≤2.1% of patients, except for "force needed for tunnelling" (91.5% good/excellent, 8.5% fair). Based on HM data, R-waves in the first month were stable at 0.70 ± 0.37 mV. Median noise burden (disabling automatic rhythm evaluation) was 0.19% (IQR 0.00-0.93), equivalent to 2.7 min (IQR 0.0-13.4) per day. In HM-transmitted ECG strips with regular sinus rhythm, P-waves were visible in 89 ± 24% of heart cycles. Patient-individual automatic Home Monitoring transmission success was 98.0% ± 5.5%. CONCLUSIONS: The novel ICM performed well in all aspects studied, including fast insertion, reliable R-wave sensing, good P-wave visibility, and highly successful HM transmissions.

Elective Cardioversion in the Era of Novel Oral Anticoagulants - Does a Nurse Administered Verbal Questionnaire for Compliance Negate the Need for Routine Transoesophageal Echocardiography?

BACKGROUND: Anticoagulation prior to elective external direct current cardioversion (EDCCV) is mandatory. The inability to monitor compliance with novel oral anticoagulants (NOACs) raises a potential safety issue. We aimed to evaluate whether a structured, nurse-led assessment of compliance prior to EDCCV ensures safety without the need for routine transoesophageal echocardiography (TOE). METHODS: Data was prospectively collected on consecutive patients undergoing EDCCV during 2014-2015. All procedures were supervised by an electrophysiology clinical nurse consultant (EPCNC). Drug compliance was verbally assessed using a standardised questionnaire by the EPCNC. Novel oral anticoagulants compliance was required for a continuous period of 3 weeks prior to EDCCV; otherwise a TOE-guided EDDCV was performed. All patients had follow-up 30 days post-procedure. RESULTS: Three hundred and eleven cardioversions were performed on 256 patients in whom 154 (49.5%) were prescribed a NOAC (rivaroxaban (n=105; 68.2%), dabigatran (n=38; 24.7%), apixaban (n=11; 7.1%)). Median age was 63 years (24-94 yrs), mean CHADS2-Vasc score was 2.0±1.5 and 138 (89.6%) were outpatients. One hundred and twenty-nine (83.8%) EDCCV were for atrial fibrillation and 25 (16.2%) for atrial flutter. Sinus rhythm was achieved in 90.3% of cases. Fourteen patients (9%) assessed as non-compliant underwent TOE. 129 (83.8%) EDCCV were performed without prior TOE. No stroke or systemic embolism was identified in any patient treated with either warfarin or a NOAC. CONCLUSIONS: A standardised, verbal questionnaire can be administered to detect NOAC non-compliance in patients undergoing EDCCV. With appropriate compliance assessment a nurse-led EDCCV without routine TOE did not significantly compromise safety in this study group.

Surface ECG and Fluoroscopy are Not Predictive of Right Ventricular Septal Lead Position Compared to Cardiac CT.

BACKGROUND: Controversy exists regarding the optimal lead position for chronic right ventricular (RV) pacing. Placing a lead at the RV septum relies upon fluoroscopy assisted by a surface 12-lead electrocardiogram (ECG). We compared the postimplant lead position determined by ECG-gated multidetector contrast-enhanced computed tomography (MDCT) with the position derived from the surface 12-lead ECG. METHODS: Eighteen patients with permanent RV leads were prospectively enrolled. Leads were placed in the RV septum (RVS) in 10 and the RV apex (RVA) in eight using fluoroscopy with anteroposterior and left anterior oblique 30° views. All patients underwent MDCT imaging and paced ECG analysis. ECG criteria were: QRS duration; QRS axis; positive or negative net QRS amplitude in leads I, aVL, V1, and V6; presence of notching in the inferior leads; and transition point in precordial leads at or after V4. RESULTS: Of the 10 leads implanted in the RVS, computed tomography (CT) imaging revealed seven to be at the anterior RV wall, two at the anteroseptal junction, and one in the true septum. For the eight RVA leads, four were anterior, two septal, and two anteroseptal. All leads implanted in the RVS met at least one ECG criteria (median 3, range 1-6). However, no criteria were specific for septal position as judged by MDCT. Mean QRS duration was 160 ± 24 ms in the RVS group compared with 168 ± 14 ms for RVA pacing (P = 0.38). CONCLUSIONS: We conclude that the surface ECG is not sufficiently accurate to determine RV septal lead tip position compared to cardiac CT.

Using the Surface ECG to Identify Right Ventricular Pacing Lead Position: A Cautionary Tale.

Chronic right ventricular (RV) apical pacing may lead to the development of heart failure in some patients. Although pacing of the RV septum has been proposed as an alternative, positioning a lead in the true septum has proven challenging. In addition to fluoroscopy at implant, it has been suggested that 12-lead surface electrocardiogram (ECG) can be used to determine septal lead position; however, studies show this may be inaccurate. We present a case where a change in the ECG QRS axis late after pacemaker insertion with an active fixation lead highlights the difficulties of ECG localization of pacing leads.

Characteristics of Cavotricuspid Isthmus Ablation for Atrial Flutter Guided by Novel Parameters Using a Contact Force Catheter.

INTRODUCTION: This study sought to investigate specific contact force (CF) parameters to guide cavotricuspid isthmus (CTI) ablation and compare the outcome with a historical control cohort. METHODS AND RESULTS: Patients (30) undergoing CTI ablation were enrolled prospectively in the Study cohort and compared with a retrospective Control cohort of 30 patients. Ablation in the Study cohort was performed using CF parameters >10 g and <40 g and a Force Time Integral (FTI) of 800 ± 10 g. The Control cohort underwent traditionally guided CTI ablation. Traditional parameters (electrogram and impedance change) were assessed in both cohorts. All ablations regardless of achieving targets were included in data analysis. Bidirectional CTI block was achieved in all of the Study and 27 of the Control cohort. Atrial flutter recurred in 3 (10%) patients (follow-up 564 ± 212 days) in the study cohort and in 3 (10%) patients (follow-up 804 ± 540 days) in the Control cohort. There were no major complications in either cohort. Traditional parameters correlated poorly with CF parameters. In the Study cohort, flutter recurrence was associated with significantly lower FTI and ablation duration, but was not associated with total average CF. CONCLUSION: CTI ablation can be safely performed using CF parameters guiding ablation, with similar long-term results to a historical ablation control group. Potentially CF parameters may provide adjunctive information to enable a more efficient CTI ablation. Further research is required to confirm this.

An Unusual Cause of Out-of-Hospital Cardiac Arrest Recorded on a Heartrate Monitor.

Coronary vasospasm is an uncommon, but perhaps under-recognised, cause of cardiac arrest. We present a novel case of an exercise-induced out-of-hospital cardiac arrest due to coronary vasospasm, captured on a heartrate monitor, and discuss the management options for this condition.

Cardiac Implantable Electronic Devices and End-of-Life Care: An Australian Perspective.

Cardiac implantable electronic devices (pacemakers and defibrillators) are increasingly common in modern cardiology practice, and health professionals from a variety of specialties will encounter patients with such devices on a frequent basis. This article will focus on the subset of patients who may request, or be appropriate for, device deactivation and discuss the issues surrounding end-of-life decisions, along with the ethical and legal implications of device deactivation.

Characterisation and Comparison of Acute Haemodynamic, Cardiac Biochemical and Hormonal Response to Different Ventricular Pacing Sites in the Normal Heart.

BACKGROUND: Acute cardiac response to right ventricular pacing is unknown. We aimed to assess the acute haemodynamic, biochemical and hormonal response to asynchronous right ventricular pacing and investigate whether there is a difference between an apical and outflow tract site. METHODS: In 21 patients with normal cardiac function, haemodynamics, brain natriuretic peptide and high sensitive troponin T were measured in response to 10minutes of pacing at each site in a randomised crossover fashion and compared. RESULTS: Pacing both sites there were significant increases in pulmonary capillary wedge pressures (p<0.001) and QRS width (p< 0.01). In comparison to baseline, apical pacing demonstrated significant (p<0.05) increases in arterial peptide and troponin levels and venous peptide levels. Outflow tract pacing compared to baseline demonstrated significant (p<0.05) increases in arterial peptide and venous, arterial and coronary sinus troponin. There were no significant differences in responses between sites. CONCLUSION: Asynchronous right ventricular pacing demonstrated significant increases in filling pressures, cardiac hormonal and biochemical response above baseline with very short durations of pacing (10minutes). There was no difference in response between sites. These findings imply that even very short periods of right ventricular based pacing are potentially deleterious.

A comparison of right ventricular non-apical defibrillator lead position with traditional right ventricular apical position: a single centre experience.

BACKGROUND: Implantable cardioverter defibrillator (ICD) leads have traditionally been placed at the right ventricular apex (RVA). An important minority of patients with an ICD may develop a future requirement for bradycardia support. Pacing from the RVA may be detrimental, promoting heart failure and mortality. Increasingly non-apical right ventricular (RVNA) lead positions have been suggested as an alternative pacing site. METHODS: A retrospective review of 512 patients who received an ICD at our institution between 1999 and 2011 was conducted. A comparison of lead performance characteristics was performed between RVNA sites and those at RVA. Data were collated from chart review and the pacing database. RESULTS: The mean follow-up period in the RVNA cohort was 40.4±25.9 months and in the RVA cohort it was 38±31.8 months (p=0.43). The RVNA cohort consisted of 144 leads and 368 leads in the RVA cohort. The groups had similar baseline clinical characteristics. No significant difference was detected in the proportion of patients receiving an appropriate ICD defibrillation (RVNA 10.4% vs. RVA 16.8%; p=0.07), inappropriate defibrillation (RVNA 7.6% vs. RVA 7.6%; p=0.99) or an unsuccessful defibrillation (RVNA 0% vs. RVA 1.7%; p=0.12). There was also no significant difference in the proportion of patients receiving successful anti-tachycardia pacing (ATP) (RVNA 13.2% vs. RVA 17.4%; p=0.49) or failed ATP (RVNA 2.7% vs. RVA 4.1%; p=0.25). There was no significant difference in lead impedance (p=0.99), sensing (p=0.59) and pacing threshold (p=0.34). CONCLUSION: In this large retrospective study, RVNA ICD lead had similar stability and therapy efficacy compared to the traditional RVA position. This potentially has important implications for the suitability of RVNA as an alternative site for ICD leads.

Acute transient non-physiological over-sensing in the ventricle with a DF4 lead.

The DF-4 is a new defibrillator lead technology. We present two cases of non-physiological transient ventricular over-sensing in patients who underwent implantation of an ICD for secondary prevention. Case 1 had ventricular over-sensing during pacing threshold evaluation post defibrillation testing while Case 2 had the lead integrity alert triggered immediately post discharge with transient over-sensing. No lead-connector issues were found. Case 1 was likely due to improper venting of the header and trapped air. Case 2 was hypothesized to be due to intermittent header pin non-contact secondary to blood in the header. These cases reveal that DF-4 leads are subject to both reported and potentially novel causes of transient acute ventricular over-sensing.

Seven years experience of a nurse-led elective cardioversion service in a tertiary referral centre: an observational study.

BACKGROUND: Traditionally the provision of elective external direct current cardioversion (EDCCV) for patients with atrial arrhythmias has been doctor-led. Increasing demands on hospital beds and time pressures for doctors has driven the desire for an alternative approach. We established a nurse-led cardioversion service in 2006 and present our experience. METHODS: A prospective database of patients undergoing elective EDCCV between July 2006 and July 2013 was collected. Demographic data, arrhythmia, success and immediate complications of cardioversion were recorded. RESULTS: A total of 974 EDCCV were performed on 772 patients. The mean patient age was 62.7 years, 564 (73.1%) were male. In 530 patients (69.0%) AF was the primary arrhythmia, in 242 (31.0%) atrial flutter. All EDCCVs were performed in a high dependency unit. Sinus rhythm was obtained in 692 patients (89.6%). Of 640 outpatients, 629 (98.3%) were discharged on the same day of their procedure. Eleven patients (1.7%) required admission to hospital. No patients required urgent temporary transvenous or permanent pacing, and there were no deaths in association with this procedure. CONCLUSIONS: Nurse-led elective EDCCV is a safe and effective way of restoring sinus rhythm in patients with AF or atrial flutter, with additional benefits to resource provision.

Cardiovascular implantable electrophysiological device-related infections: a review.

PURPOSE OF REVIEW: The use of cardiac implantable electrophysiological device (CIED) therapy in the management of cardiac disease is increasing with the improvements in technology of permanent pacemaker and implantable cardioverter defibrillators. Accordingly CIED-related infections are increasing and have become an important clinical problem. The purpose of this review is to summarize current literature on the epidemiology, risk factors, pathophysiology, diagnosis and management of CIED-related infections. RECENT FINDINGS: The diagnosis and management of CIED-related infections can be difficult. Recent research would suggest extraction of all CIED components, and concomitant appropriate antibiotic therapy is the principal management modality of CIED component and pocket infection. The exact duration of antibiotic therapy and timing of re-implantation still require further delineation in the absence of comparative evidence; however, improvements in technologies such as the excimer laser have enabled percutaneous extraction to be performed effectively and safely in the vast majority of patients. Differentiating CIED-related infection from noninfected mechanical issues that may not require extraction or antibiotics can be very difficult. Research is continuing into better methods to diagnose and treat infection. SUMMARY: CIED-related infections are an important clinical problem with ongoing research to improve diagnosis and treatment. Currently, percutaneous CIED extraction and antibiotic therapy are the mainstay of treatment.