Emily Kotschet - Academia.edu (original) (raw)

Papers by Emily Kotschet

Research paper thumbnail of Cardiac injury after percutaneous catheter ablation for atrial fibrillation. Europace 2008;10:273–5

Aims Small elevations in troponin T levels have been shown with limited radiofrequency (RF) ablat... more Aims Small elevations in troponin T levels have been shown with limited radiofrequency (RF) ablation procedures for supraventricular tachycardia, usually to levels below the threshold for ischaemia or infarction. Left atrial catheter ablation for atrial fibrillation (AF) requires far more RF energy, therefore could be expected to have greater elevation in troponin T. We determined troponin T levels before and after ablation in these patients to evaluate the amount of rise with this ablation. Methods All patients undergoing pulmonary vein isolation (PVI) from May 2004 to October 2004 had tro-ponin T levels measured 4 h following completion of the procedure. The first 30 patients also had a tro-ponin T level measured 1 h prior to PVI to establish a baseline reference. Results Sixty patients were studied, with 81.7 % males and a mean age of 54.6+9.9 years. No patient had underlying structural heart disease. The baseline troponin T level was normal (,0.01 mg/L) in all 30 patients. Post-...

Research paper thumbnail of Junctional ectopic tachycardia (JET)

Journal of Arrhythmia, 2020

Junctional ectopic tachycardia (JET) is a tachyarrhythmia arising from the atrioventricular node ... more Junctional ectopic tachycardia (JET) is a tachyarrhythmia arising from the atrioventricular node and His bundle area. Enhanced normal automaticity has been postulated as the mechanism of JET in the majority of patients. It is more common in children and can be seen as congenital or in postoperative settings. It is often a narrow complex tachycardia but can present as a wide complex tachycardia as a result of aberrant conduction. Its differentiation from other arrhythmias especially atrioventricular nodal reentrant tachycardia (AVNRT) can be challenging. Medical treatment of JET is difficult, and catheter ablation remains the mainstay of treatment in refractory cases with a high risk of atrioventricular block and recurrence.

Research paper thumbnail of Hybrid Totally Thoracoscopic Maze and Catheter Ablation for Long Standing Persistent Atrial Fibrillation: Initial Experience

Atrial Fibrillation is now a pandemic in our ageing community. Although Cox (1987) devised a surg... more Atrial Fibrillation is now a pandemic in our ageing community. Although Cox (1987) devised a surgical procedure with near-universal curative success, widespread clinical endorsement has not followed. Meanwhile, catheter-based interventions have flourished. For persistent Atrial Fibrillation (AF), however, an isolated endocardial approach has significant limitations: procedural times are long, carry risk, and the outcomes are poor. By combining left atrial endocardial and epicardial interventions with staged mapping, we optimise the benefits of both approaches. We report our first twenty-five consecutive patients undergoing Totally-Thoracoscopic-Maze procedure (TT), followed at three months by staged electrophysiologic (EP) mapping. Selected patients had symptomatic, lone atrial fibrillation, of greater than twelve months duration, having failed to revert despite multiple antiarrhythmic agents. Patients were excluded if they had received prior EP intervention or required additional p...

Research paper thumbnail of B-PO02-063 Electrogram R-Wave Amplitude for Different Sensing Vectors Across Different Postures for Patients with an Extravascular Implantable Cardioverter Defibrillator

Research paper thumbnail of B-PO04-065 Two-Year Chronic Follow-Up from the Pilot Study of a Substernal Extravascular Implantable Cardioverter Defibrillator

Research paper thumbnail of B-PO01-043 the Extravascular Icd: Characterization of Anatomical Parameters Impacting Substernal Implantation and Defibrillation Efficacy

Research paper thumbnail of B-PO02-066 Virtual Analysis of Ventricular Fibrillation Sensing

Research paper thumbnail of Design and Preliminary Results of Sensing and Detection for an Extravascular Implantable Cardioverter-Defibrillator

JACC: Clinical Electrophysiology

Research paper thumbnail of An up‐to‐date review of cardiac pacemakers and implantable cardioverter defibrillators

Journal of Medical Imaging and Radiation Oncology

Cardiac pacemakers are one of the most frequently encountered cardiac devices seen on chest imagi... more Cardiac pacemakers are one of the most frequently encountered cardiac devices seen on chest imaging. They may include single or dual chamber pacemakers, automated implantable cardioverter defibrillators (AICD), biventricular pacemakers used for cardiac resynchronisation therapy (CRT), wireless CRT, leadless pacemakers, and subcutaneous implantable cardioverter defibrillators (SICD). This review aims to provide an up-to-date review on current implantable pacemaker and defibrillator devices.

Research paper thumbnail of First-in-Human Chronic Implant Experience of the Substernal Extravascular Implantable Cardioverter-Defibrillator

JACC: Clinical Electrophysiology

OBJECTIVES The aim of this study was to evaluate the safety and performance of an extravascular (... more OBJECTIVES The aim of this study was to evaluate the safety and performance of an extravascular (EV) implantable cardioverter-defibrillator (ICD). BACKGROUND Limitations of existing transvenous and subcutaneous ICD systems include lead reliability and morbidity issues associated with ICD lead implantation in the vasculature or lack of pacing therapies (e.g., antitachycardia pacing) in subcutaneous systems. The EV defibrillator uses a novel substernal lead placement to address these limitations. METHODS This was a prospective, nonrandomized, chronic pilot study conducted at 4 centers in Australia and New Zealand. Participants were 21 patients referred for ICD implantation. Patients received EV ICD systems. Data collection included major systemic and procedural adverse events, defibrillation testing at implantation, and sensing and pacing thresholds. RESULTS Among 20 patients who underwent successful implantation, the median defibrillation threshold was 15 J, and 90% passed defibrillation testing with a ≥10-J safety margin. Mean R-wave amplitude was 3.4 ± 2.0 mV, mean ventricular fibrillation amplitude was 2.8 ± 1.7 mV, and pacing was successful in 95% at ≤10 V. There were no intraprocedural complications. Two patients have undergone elective chronic system removal since hospital discharge. In the 15 patients presently implanted, the systems are stable in long-term follow-up. CONCLUSIONS This first-in-human evaluation of an EV ICD demonstrated the feasibility of substernal lead placement, defibrillation, and pacing with a chronically implanted system. There were no acute major complications, and pacing, defibrillation, and sensing performance at implantation were successful in most patients. (Extravascular ICD Pilot Study [EV ICD]; NCT03608670).

Research paper thumbnail of Catheter Ablation Versus Medication in Atrial Fibrillation and Systolic Dysfunction

JACC: Clinical Electrophysiology

OBJECTIVES This study sought to determine the long-term outcomes of restoring sinus rhythm with c... more OBJECTIVES This study sought to determine the long-term outcomes of restoring sinus rhythm with catheter ablation (CA). BACKGROUND The CAMERA-MRI (Catheter Ablation Versus Medical Rate Control in Atrial Fibrillation and Heart Failure-An MRI-Guided Multicenter Randomized Controlled Trial) study demonstrated that restoration of sinus rhythm with CA significantly improved left ventricular ejection fraction (LVEF) compared with medical rate control (MRC) at 6 months in persistent atrial fibrillation and otherwise unexplained systolic heart failure. However, the long-term outcomes have not been reported. METHODS Patients enrolled in the CAMERA-MRI study were followed for 4 years with echocardiogram and cardiac magnetic resonance. CA involved pulmonary vein isolation and posterior left atrial wall isolation in 94%. Patients crossed over to CA after 6-month study duration. Arrhythmia burden was determined with implanted cardiac monitors or cardiac devices. RESULTS Sixty-six patients (age 62 ± 10 years, atrial fibrillation duration of 22 ± 16 months, and LVEF 33 ± 9%) were randomized 1:1 to CA versus MRC. Eighteen of 33 patients crossed over from MRC group to CA group. At 4.0 ± 0.9 years, atrial fibrillation recurred in 27 patients (57%) in the CA group with a mean burden of 10.6 ± 21.2% after 1.4 ± 0.6 procedures. There was an absolute increase in LVEF with CA of 16.4 ± 13.3% compared with 8.6 ± 7.6% in MRC (p = 0.001). In the CA group, the absence of ventricular late gadolinium enhancement was associated with a greater improvement in absolute LVEF (19 ± 13% vs. 10 ± 11% in the late gadolinium enhancement-positive group; p = 0.04) and LVEF normalization in 19 patients (58%) versus 4 patients (18%) in the late gadolinium enhancement-positive group (p = 0.008) at 4.0 ± 0.9 years follow-up. CONCLUSIONS CA is superior to MRC in improving LVEF in the long term in patients with atrial fibrillation and systolic heart failure. The greatest recovery in systolic function was demonstrated in the absence of ventricular fibrosis on cardiac magnetic resonance.

Research paper thumbnail of Long-term longevity and clinical outcomes of Linox S/SD implantable cardioverter-defibrillator leads: a single-center experience

Journal of Interventional Cardiac Electrophysiology

Purpose Since the introduction of the Biotronik Linox S/SD leads in 2006, there have been multipl... more Purpose Since the introduction of the Biotronik Linox S/SD leads in 2006, there have been multiple reports of premature lead failure. The purpose of this study was to investigate the longevity of the Linox S/SD leads and to identify the possible predictors of lead failure in a single tertiary implant center. Methods We retrospectively reviewed patients who underwent implantation of Linox S/SD leads or Sorin Vigila 1CR/2CR leads (the same Linox S/SD leads marketed by Sorin) at our center. The cumulative lead survival was estimated using the Kaplan-Meier curve, and variables associated with lead failure were assessed by Cox proportional hazard model. Results A total of 187 patients (154 (82%) male) underwent Linox S/SD or Vigila 1CR/2CR implantation between 2007 and 2013. During follow-up with a median time of 75 months, nine lead failures were identified (4.8%). The mean and median times from lead implantation to lead failure were 70.7 ± 21 months and 64 (45–111) months, respectively. The cumulative survival probability for the Linox S/SD at 5 years was 97.1% and at 12 years was 90.3%. Non-physiological high-rate sensing was the most common type of lead failure in patients. In two-thirds of these patients, this led to inappropriate shock. We did not find any significant relationships between patients’ clinical and procedural characteristics and lead failure. Conclusions At our center, the 5-year lead survival of the Linox S/SD has been better than reports from other centers. The majority of lead failures presented as non-physiological high-rate sensing with subsequent inappropriate therapy.

Research paper thumbnail of Alcohol Abstinence in Drinkers with Atrial Fibrillation

New England Journal of Medicine

BACKGROUND Excessive alcohol consumption is associated with incident atrial fibrillation and adve... more BACKGROUND Excessive alcohol consumption is associated with incident atrial fibrillation and adverse atrial remodeling; however, the effect of abstinence from alcohol on secondary prevention of atrial fibrillation is unclear. METHODS We conducted a multicenter, prospective, open-label, randomized, controlled trial at six hospitals in Australia. Adults who consumed 10 or more standard drinks (with 1 standard drink containing approximately 12 g of pure alcohol) per week and who had paroxysmal or persistent atrial fibrillation in sinus rhythm at baseline were randomly assigned in a 1:1 ratio to either abstain from alcohol or continue their usual alcohol consumption. The two primary end points were freedom from recurrence of atrial fibrillation (after a 2-week "blanking period") and total atrial fibrillation burden (proportion of time in atrial fibrillation) during 6 months of follow-up. RESULTS Of 140 patients who underwent randomization (85% men; mean [±SD] age, 62±9 years), 70 were assigned to the abstinence group and 70 to the control group. Patients in the abstinence group reduced their alcohol intake from 16.8±7.7 to 2.1±3.7 standard drinks per week (a reduction of 87.5%), and patients in the control group reduced their alcohol intake from 16.4±6.9 to 13.2±6.5 drinks per week (a reduction of 19.5%). After a 2-week blanking period, atrial fibrillation recurred in 37 of 70 patients (53%) in the abstinence group and in 51 of 70 patients (73%) in the control group. The abstinence group had a longer period before recurrence of atrial fibrillation than the control group (hazard ratio, 0.55; 95% confidence interval, 0.36 to 0.84; P = 0.005). The atrial fibrillation burden over 6 months of follow-up was significantly lower in the abstinence group than in the control group (median percentage of time in atrial fibrillation, 0.5% [interquartile range, 0.0 to 3.0] vs. 1.2% [interquartile range, 0.0 to 10.3]; P = 0.01). CONCLUSIONS Abstinence from alcohol reduced arrhythmia recurrences in regular drinkers with atrial fibrillation. (Funded by the Government of Victoria Operational Infrastructure Support Program and others; Australian New Zealand Clinical Trials Registry number, ACTRN12616000256471.).

Research paper thumbnail of Pacemaker‐mediated arrhythmias

Journal of Arrhythmia

Pacemakers can be directly involved in initiating or sustaining different forms of arrhythmia. Th... more Pacemakers can be directly involved in initiating or sustaining different forms of arrhythmia. These can cause symptoms such as dyspnea, palpitations, and decompensated heart failure. Early detection of these arrhythmias and optimal pacemaker programming is pivotal. The aim of this review article is to summarize the different types of pacemaker-mediated arrhythmias, their predisposing factors, and mechanisms of prevention or termination. K E Y W O R D S endless loop tachycardia, pacemaker-mediated arrhythmia, retrograde ventriculo-atrial conduction This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

Research paper thumbnail of Increased Incidence of Noise in the Tendril Pacemaker Lead Detected via Remote Monitoring

Heart, Lung and Circulation

BACKGROUND Prior studies suggest increased rates of noise on the Tendril (St Jude Medical/Abbott,... more BACKGROUND Prior studies suggest increased rates of noise on the Tendril (St Jude Medical/Abbott, St. Paul, MN, USA) pacemaker lead. We aim to assess the incidence of lead noise in the Tendril and 5076 (Medtronic PLC, Minneapolis, MN, USA) pacemaker leads in our cohort and in the process assess the utility of remote monitoring for identifying lead malfunction. METHODS Deidentified, multi-centre, prospectively collected observational cohort data was obtained to assess the incidence of noise on the Tendril and 5076 pacemaker leads. RESULTS 148 Tendril and 737 CapSureFix Novus 5076 (Medtronic, MN, USA) pacemaker leads were remotely monitored. Incidence of noise on the Tendril was 8% and 0.27% on the CapSureFix Novus. CONCLUSION Rates of noise in the Tendril lead are higher than a market competitor. Remote monitoring is useful in detecting this concerning anomaly.

Research paper thumbnail of Inappropriate Shock Due to Myopotential Oversensing in a Patient With Subcutaneous Implantable Cardioverter-Defibrillator

Heart, Lung and Circulation

Research paper thumbnail of Micra implantation in a patient with transposition of great arteries

Pacing and Clinical Electrophysiology

We describe a 56‐year‐old male with transposition of the great arteries and Mustard repair, super... more We describe a 56‐year‐old male with transposition of the great arteries and Mustard repair, superior vena cava obstruction, atrial fibrillation, and progressive deterioration of his epicardial lead performance. We were successful in deploying of Micra (Medtronic, Minneapolis, MN, USA) at the septo‐apical area of his nonsystemic ventricle in a stable position with satisfactory pacing and sensing thresholds.

Research paper thumbnail of Loss of cardiac resynchronization therapy in a patient with a biventricular implantable cardioverter-defibrillator

Journal of arrhythmia, 2017

Here, we discuss the case of a man with a history of ischemic cardiomyopathy and cardiac resynchr... more Here, we discuss the case of a man with a history of ischemic cardiomyopathy and cardiac resynchronization therapy defibrillator implantation, who presented to emergency department with decompensated heart failure due to the loss of resynchronization therapy. The reason for the malfunction was left ventricle upper rate interval lock-in due to inappropriate programming of the device.

Research paper thumbnail of Long-term pacemaker dependency and impact of pacing on mortality following transcatheter aortic valve replacement with the LOTUS valve

Catheterization and cardiovascular interventions : official journal of the Society for Cardiac Angiography & Interventions, Jan 4, 2018

To determine permanent pacemaker (PPM) dependency following transcatheter aortic valve replacemen... more To determine permanent pacemaker (PPM) dependency following transcatheter aortic valve replacement (TAVR) with the Lotus™ valve system (Boston Scientific), and the impact of PPM implantation on long-term morbidity and mortality. Conduction abnormalities are among the most common complications following TAVR. Limited studies have assessed pacing dependency following TAVR. Consecutive patients (n = 166) with severe aortic stenosis who underwent TAVR with the Lotus valve system were prospectively recruited from a single-center. PPMs were implanted according to standard clinical criteria. Patients were followed in-hospital and at 1, 3, 6, and 12 months to determine pacemaker dependency and clinical outcomes. Fourteen patients with a pre-existing PPM (8%) were excluded with the remaining 152 patients aged 83.6 ± 5.6 years and 46% male. PPMs were implanted 3.8 ± 4 days post-TAVR in 38/152 patients (25%). Indication for PPM was complete heart block in 29 (76%) of patients. At 30-day and on...

Research paper thumbnail of Aborted sudden cardiac death in a patient with implantable loop recorder

Indian Pacing and Electrophysiology Journal

We discuss a 46-year-old man with history of hypertension and inferior wall myocardial infarction... more We discuss a 46-year-old man with history of hypertension and inferior wall myocardial infarction and mild left ventricular dysfunction who presented with aborted sudden cardiac death due to episodes of ventricular tachyarrhythmia detected by a Reveal-LINQ which had been implanted one year prior to presentation.

Research paper thumbnail of Cardiac injury after percutaneous catheter ablation for atrial fibrillation. Europace 2008;10:273–5

Aims Small elevations in troponin T levels have been shown with limited radiofrequency (RF) ablat... more Aims Small elevations in troponin T levels have been shown with limited radiofrequency (RF) ablation procedures for supraventricular tachycardia, usually to levels below the threshold for ischaemia or infarction. Left atrial catheter ablation for atrial fibrillation (AF) requires far more RF energy, therefore could be expected to have greater elevation in troponin T. We determined troponin T levels before and after ablation in these patients to evaluate the amount of rise with this ablation. Methods All patients undergoing pulmonary vein isolation (PVI) from May 2004 to October 2004 had tro-ponin T levels measured 4 h following completion of the procedure. The first 30 patients also had a tro-ponin T level measured 1 h prior to PVI to establish a baseline reference. Results Sixty patients were studied, with 81.7 % males and a mean age of 54.6+9.9 years. No patient had underlying structural heart disease. The baseline troponin T level was normal (,0.01 mg/L) in all 30 patients. Post-...

Research paper thumbnail of Junctional ectopic tachycardia (JET)

Journal of Arrhythmia, 2020

Junctional ectopic tachycardia (JET) is a tachyarrhythmia arising from the atrioventricular node ... more Junctional ectopic tachycardia (JET) is a tachyarrhythmia arising from the atrioventricular node and His bundle area. Enhanced normal automaticity has been postulated as the mechanism of JET in the majority of patients. It is more common in children and can be seen as congenital or in postoperative settings. It is often a narrow complex tachycardia but can present as a wide complex tachycardia as a result of aberrant conduction. Its differentiation from other arrhythmias especially atrioventricular nodal reentrant tachycardia (AVNRT) can be challenging. Medical treatment of JET is difficult, and catheter ablation remains the mainstay of treatment in refractory cases with a high risk of atrioventricular block and recurrence.

Research paper thumbnail of Hybrid Totally Thoracoscopic Maze and Catheter Ablation for Long Standing Persistent Atrial Fibrillation: Initial Experience

Atrial Fibrillation is now a pandemic in our ageing community. Although Cox (1987) devised a surg... more Atrial Fibrillation is now a pandemic in our ageing community. Although Cox (1987) devised a surgical procedure with near-universal curative success, widespread clinical endorsement has not followed. Meanwhile, catheter-based interventions have flourished. For persistent Atrial Fibrillation (AF), however, an isolated endocardial approach has significant limitations: procedural times are long, carry risk, and the outcomes are poor. By combining left atrial endocardial and epicardial interventions with staged mapping, we optimise the benefits of both approaches. We report our first twenty-five consecutive patients undergoing Totally-Thoracoscopic-Maze procedure (TT), followed at three months by staged electrophysiologic (EP) mapping. Selected patients had symptomatic, lone atrial fibrillation, of greater than twelve months duration, having failed to revert despite multiple antiarrhythmic agents. Patients were excluded if they had received prior EP intervention or required additional p...

Research paper thumbnail of B-PO02-063 Electrogram R-Wave Amplitude for Different Sensing Vectors Across Different Postures for Patients with an Extravascular Implantable Cardioverter Defibrillator

Research paper thumbnail of B-PO04-065 Two-Year Chronic Follow-Up from the Pilot Study of a Substernal Extravascular Implantable Cardioverter Defibrillator

Research paper thumbnail of B-PO01-043 the Extravascular Icd: Characterization of Anatomical Parameters Impacting Substernal Implantation and Defibrillation Efficacy

Research paper thumbnail of B-PO02-066 Virtual Analysis of Ventricular Fibrillation Sensing

Research paper thumbnail of Design and Preliminary Results of Sensing and Detection for an Extravascular Implantable Cardioverter-Defibrillator

JACC: Clinical Electrophysiology

Research paper thumbnail of An up‐to‐date review of cardiac pacemakers and implantable cardioverter defibrillators

Journal of Medical Imaging and Radiation Oncology

Cardiac pacemakers are one of the most frequently encountered cardiac devices seen on chest imagi... more Cardiac pacemakers are one of the most frequently encountered cardiac devices seen on chest imaging. They may include single or dual chamber pacemakers, automated implantable cardioverter defibrillators (AICD), biventricular pacemakers used for cardiac resynchronisation therapy (CRT), wireless CRT, leadless pacemakers, and subcutaneous implantable cardioverter defibrillators (SICD). This review aims to provide an up-to-date review on current implantable pacemaker and defibrillator devices.

Research paper thumbnail of First-in-Human Chronic Implant Experience of the Substernal Extravascular Implantable Cardioverter-Defibrillator

JACC: Clinical Electrophysiology

OBJECTIVES The aim of this study was to evaluate the safety and performance of an extravascular (... more OBJECTIVES The aim of this study was to evaluate the safety and performance of an extravascular (EV) implantable cardioverter-defibrillator (ICD). BACKGROUND Limitations of existing transvenous and subcutaneous ICD systems include lead reliability and morbidity issues associated with ICD lead implantation in the vasculature or lack of pacing therapies (e.g., antitachycardia pacing) in subcutaneous systems. The EV defibrillator uses a novel substernal lead placement to address these limitations. METHODS This was a prospective, nonrandomized, chronic pilot study conducted at 4 centers in Australia and New Zealand. Participants were 21 patients referred for ICD implantation. Patients received EV ICD systems. Data collection included major systemic and procedural adverse events, defibrillation testing at implantation, and sensing and pacing thresholds. RESULTS Among 20 patients who underwent successful implantation, the median defibrillation threshold was 15 J, and 90% passed defibrillation testing with a ≥10-J safety margin. Mean R-wave amplitude was 3.4 ± 2.0 mV, mean ventricular fibrillation amplitude was 2.8 ± 1.7 mV, and pacing was successful in 95% at ≤10 V. There were no intraprocedural complications. Two patients have undergone elective chronic system removal since hospital discharge. In the 15 patients presently implanted, the systems are stable in long-term follow-up. CONCLUSIONS This first-in-human evaluation of an EV ICD demonstrated the feasibility of substernal lead placement, defibrillation, and pacing with a chronically implanted system. There were no acute major complications, and pacing, defibrillation, and sensing performance at implantation were successful in most patients. (Extravascular ICD Pilot Study [EV ICD]; NCT03608670).

Research paper thumbnail of Catheter Ablation Versus Medication in Atrial Fibrillation and Systolic Dysfunction

JACC: Clinical Electrophysiology

OBJECTIVES This study sought to determine the long-term outcomes of restoring sinus rhythm with c... more OBJECTIVES This study sought to determine the long-term outcomes of restoring sinus rhythm with catheter ablation (CA). BACKGROUND The CAMERA-MRI (Catheter Ablation Versus Medical Rate Control in Atrial Fibrillation and Heart Failure-An MRI-Guided Multicenter Randomized Controlled Trial) study demonstrated that restoration of sinus rhythm with CA significantly improved left ventricular ejection fraction (LVEF) compared with medical rate control (MRC) at 6 months in persistent atrial fibrillation and otherwise unexplained systolic heart failure. However, the long-term outcomes have not been reported. METHODS Patients enrolled in the CAMERA-MRI study were followed for 4 years with echocardiogram and cardiac magnetic resonance. CA involved pulmonary vein isolation and posterior left atrial wall isolation in 94%. Patients crossed over to CA after 6-month study duration. Arrhythmia burden was determined with implanted cardiac monitors or cardiac devices. RESULTS Sixty-six patients (age 62 ± 10 years, atrial fibrillation duration of 22 ± 16 months, and LVEF 33 ± 9%) were randomized 1:1 to CA versus MRC. Eighteen of 33 patients crossed over from MRC group to CA group. At 4.0 ± 0.9 years, atrial fibrillation recurred in 27 patients (57%) in the CA group with a mean burden of 10.6 ± 21.2% after 1.4 ± 0.6 procedures. There was an absolute increase in LVEF with CA of 16.4 ± 13.3% compared with 8.6 ± 7.6% in MRC (p = 0.001). In the CA group, the absence of ventricular late gadolinium enhancement was associated with a greater improvement in absolute LVEF (19 ± 13% vs. 10 ± 11% in the late gadolinium enhancement-positive group; p = 0.04) and LVEF normalization in 19 patients (58%) versus 4 patients (18%) in the late gadolinium enhancement-positive group (p = 0.008) at 4.0 ± 0.9 years follow-up. CONCLUSIONS CA is superior to MRC in improving LVEF in the long term in patients with atrial fibrillation and systolic heart failure. The greatest recovery in systolic function was demonstrated in the absence of ventricular fibrosis on cardiac magnetic resonance.

Research paper thumbnail of Long-term longevity and clinical outcomes of Linox S/SD implantable cardioverter-defibrillator leads: a single-center experience

Journal of Interventional Cardiac Electrophysiology

Purpose Since the introduction of the Biotronik Linox S/SD leads in 2006, there have been multipl... more Purpose Since the introduction of the Biotronik Linox S/SD leads in 2006, there have been multiple reports of premature lead failure. The purpose of this study was to investigate the longevity of the Linox S/SD leads and to identify the possible predictors of lead failure in a single tertiary implant center. Methods We retrospectively reviewed patients who underwent implantation of Linox S/SD leads or Sorin Vigila 1CR/2CR leads (the same Linox S/SD leads marketed by Sorin) at our center. The cumulative lead survival was estimated using the Kaplan-Meier curve, and variables associated with lead failure were assessed by Cox proportional hazard model. Results A total of 187 patients (154 (82%) male) underwent Linox S/SD or Vigila 1CR/2CR implantation between 2007 and 2013. During follow-up with a median time of 75 months, nine lead failures were identified (4.8%). The mean and median times from lead implantation to lead failure were 70.7 ± 21 months and 64 (45–111) months, respectively. The cumulative survival probability for the Linox S/SD at 5 years was 97.1% and at 12 years was 90.3%. Non-physiological high-rate sensing was the most common type of lead failure in patients. In two-thirds of these patients, this led to inappropriate shock. We did not find any significant relationships between patients’ clinical and procedural characteristics and lead failure. Conclusions At our center, the 5-year lead survival of the Linox S/SD has been better than reports from other centers. The majority of lead failures presented as non-physiological high-rate sensing with subsequent inappropriate therapy.

Research paper thumbnail of Alcohol Abstinence in Drinkers with Atrial Fibrillation

New England Journal of Medicine

BACKGROUND Excessive alcohol consumption is associated with incident atrial fibrillation and adve... more BACKGROUND Excessive alcohol consumption is associated with incident atrial fibrillation and adverse atrial remodeling; however, the effect of abstinence from alcohol on secondary prevention of atrial fibrillation is unclear. METHODS We conducted a multicenter, prospective, open-label, randomized, controlled trial at six hospitals in Australia. Adults who consumed 10 or more standard drinks (with 1 standard drink containing approximately 12 g of pure alcohol) per week and who had paroxysmal or persistent atrial fibrillation in sinus rhythm at baseline were randomly assigned in a 1:1 ratio to either abstain from alcohol or continue their usual alcohol consumption. The two primary end points were freedom from recurrence of atrial fibrillation (after a 2-week "blanking period") and total atrial fibrillation burden (proportion of time in atrial fibrillation) during 6 months of follow-up. RESULTS Of 140 patients who underwent randomization (85% men; mean [±SD] age, 62±9 years), 70 were assigned to the abstinence group and 70 to the control group. Patients in the abstinence group reduced their alcohol intake from 16.8±7.7 to 2.1±3.7 standard drinks per week (a reduction of 87.5%), and patients in the control group reduced their alcohol intake from 16.4±6.9 to 13.2±6.5 drinks per week (a reduction of 19.5%). After a 2-week blanking period, atrial fibrillation recurred in 37 of 70 patients (53%) in the abstinence group and in 51 of 70 patients (73%) in the control group. The abstinence group had a longer period before recurrence of atrial fibrillation than the control group (hazard ratio, 0.55; 95% confidence interval, 0.36 to 0.84; P = 0.005). The atrial fibrillation burden over 6 months of follow-up was significantly lower in the abstinence group than in the control group (median percentage of time in atrial fibrillation, 0.5% [interquartile range, 0.0 to 3.0] vs. 1.2% [interquartile range, 0.0 to 10.3]; P = 0.01). CONCLUSIONS Abstinence from alcohol reduced arrhythmia recurrences in regular drinkers with atrial fibrillation. (Funded by the Government of Victoria Operational Infrastructure Support Program and others; Australian New Zealand Clinical Trials Registry number, ACTRN12616000256471.).

Research paper thumbnail of Pacemaker‐mediated arrhythmias

Journal of Arrhythmia

Pacemakers can be directly involved in initiating or sustaining different forms of arrhythmia. Th... more Pacemakers can be directly involved in initiating or sustaining different forms of arrhythmia. These can cause symptoms such as dyspnea, palpitations, and decompensated heart failure. Early detection of these arrhythmias and optimal pacemaker programming is pivotal. The aim of this review article is to summarize the different types of pacemaker-mediated arrhythmias, their predisposing factors, and mechanisms of prevention or termination. K E Y W O R D S endless loop tachycardia, pacemaker-mediated arrhythmia, retrograde ventriculo-atrial conduction This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

Research paper thumbnail of Increased Incidence of Noise in the Tendril Pacemaker Lead Detected via Remote Monitoring

Heart, Lung and Circulation

BACKGROUND Prior studies suggest increased rates of noise on the Tendril (St Jude Medical/Abbott,... more BACKGROUND Prior studies suggest increased rates of noise on the Tendril (St Jude Medical/Abbott, St. Paul, MN, USA) pacemaker lead. We aim to assess the incidence of lead noise in the Tendril and 5076 (Medtronic PLC, Minneapolis, MN, USA) pacemaker leads in our cohort and in the process assess the utility of remote monitoring for identifying lead malfunction. METHODS Deidentified, multi-centre, prospectively collected observational cohort data was obtained to assess the incidence of noise on the Tendril and 5076 pacemaker leads. RESULTS 148 Tendril and 737 CapSureFix Novus 5076 (Medtronic, MN, USA) pacemaker leads were remotely monitored. Incidence of noise on the Tendril was 8% and 0.27% on the CapSureFix Novus. CONCLUSION Rates of noise in the Tendril lead are higher than a market competitor. Remote monitoring is useful in detecting this concerning anomaly.

Research paper thumbnail of Inappropriate Shock Due to Myopotential Oversensing in a Patient With Subcutaneous Implantable Cardioverter-Defibrillator

Heart, Lung and Circulation

Research paper thumbnail of Micra implantation in a patient with transposition of great arteries

Pacing and Clinical Electrophysiology

We describe a 56‐year‐old male with transposition of the great arteries and Mustard repair, super... more We describe a 56‐year‐old male with transposition of the great arteries and Mustard repair, superior vena cava obstruction, atrial fibrillation, and progressive deterioration of his epicardial lead performance. We were successful in deploying of Micra (Medtronic, Minneapolis, MN, USA) at the septo‐apical area of his nonsystemic ventricle in a stable position with satisfactory pacing and sensing thresholds.

Research paper thumbnail of Loss of cardiac resynchronization therapy in a patient with a biventricular implantable cardioverter-defibrillator

Journal of arrhythmia, 2017

Here, we discuss the case of a man with a history of ischemic cardiomyopathy and cardiac resynchr... more Here, we discuss the case of a man with a history of ischemic cardiomyopathy and cardiac resynchronization therapy defibrillator implantation, who presented to emergency department with decompensated heart failure due to the loss of resynchronization therapy. The reason for the malfunction was left ventricle upper rate interval lock-in due to inappropriate programming of the device.

Research paper thumbnail of Long-term pacemaker dependency and impact of pacing on mortality following transcatheter aortic valve replacement with the LOTUS valve

Catheterization and cardiovascular interventions : official journal of the Society for Cardiac Angiography & Interventions, Jan 4, 2018

To determine permanent pacemaker (PPM) dependency following transcatheter aortic valve replacemen... more To determine permanent pacemaker (PPM) dependency following transcatheter aortic valve replacement (TAVR) with the Lotus™ valve system (Boston Scientific), and the impact of PPM implantation on long-term morbidity and mortality. Conduction abnormalities are among the most common complications following TAVR. Limited studies have assessed pacing dependency following TAVR. Consecutive patients (n = 166) with severe aortic stenosis who underwent TAVR with the Lotus valve system were prospectively recruited from a single-center. PPMs were implanted according to standard clinical criteria. Patients were followed in-hospital and at 1, 3, 6, and 12 months to determine pacemaker dependency and clinical outcomes. Fourteen patients with a pre-existing PPM (8%) were excluded with the remaining 152 patients aged 83.6 ± 5.6 years and 46% male. PPMs were implanted 3.8 ± 4 days post-TAVR in 38/152 patients (25%). Indication for PPM was complete heart block in 29 (76%) of patients. At 30-day and on...

Research paper thumbnail of Aborted sudden cardiac death in a patient with implantable loop recorder

Indian Pacing and Electrophysiology Journal

We discuss a 46-year-old man with history of hypertension and inferior wall myocardial infarction... more We discuss a 46-year-old man with history of hypertension and inferior wall myocardial infarction and mild left ventricular dysfunction who presented with aborted sudden cardiac death due to episodes of ventricular tachyarrhythmia detected by a Reveal-LINQ which had been implanted one year prior to presentation.