Publications by authors named "Michael P Riley"
Background: Patients undergoing first-time atrial fibrillation (AF) ablation can benefit from targeting non-pulmonary vein (PV) triggers. Preprocedural identification of high-risk individuals can guide planning of ablation strategy. This study aimed to create a preprocedural screening tool to identify patients at risk of non-PV triggers during first-time AF ablation.
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- The study investigates the long-term risk of damage to the right coronary artery (RCA) after patients undergo radiofrequency ablation (RFA) for atrial flutter related to the cavotricuspid isthmus (CTI).
- A comparison was made between patients who had CTI RFA and those who only received ablation for atrial fibrillation (AF), with coronary angiography performed afterward to evaluate any differences in RCA stenosis.
- Results indicate that there were no significant differences in the incidence or severity of RCA stenoses between the two groups, suggesting that CTI RFA does not increase the risk of RCA damage in the long term.
Background: The importance of nonpulmonary vein (PV) triggers for the initiation/recurrence of atrial fibrillation (AF) is well established.
Objectives: This study sought to assess the incremental benefit of provocative maneuvers for identifying non-PV triggers.
Methods: We included consecutive patients undergoing first-time AF ablation between 2020 and 2022.
Incidental ablation of ganglionated plexus during atrial fibrillation ablation.
J Interv Card Electrophysiol
July 2024
Article Synopsis
- Cardioneuroablation targeting autonomic nerves is used in treating atrial fibrillation (AF), with the study suggesting that incidental ablation might enhance the effectiveness of pulmonary vein isolation (PVI).
- The researchers evaluated patients who underwent PVI from 2021 to 2023, finding that electrograms in areas related to ganglionated plexus (GP) largely overlap with the ablation lesions.
- Out of 52 patients, 96% showed accidental overlap between PVI and GP areas, with those regions having a significant link to improved heart rate and reduced recurrence of AF over the following months.
Article Synopsis
- The study examines the effectiveness of endocardial (ENDO) ablation in treating arrhythmogenic right ventricular cardiomyopathy (ARVC), specifically focusing on its long-term outcomes and factors influencing survival without ventricular tachycardia (VT).
- A total of 74 patients with ARVC underwent ENDO-only VT ablation between 1998 and 2020, with about 66% achieving noninducibility of VT and a median follow-up of 6.6 years revealing that over 54% remained free of VT recurrence.
- Important predictors for long-term VT-free survival included being over 45 years at diagnosis and achieving VT noninducibility, suggesting that ENDO-only ablation could be a viable initial
Article Synopsis
- Epicardial access is important during ventricular tachycardia ablation, and the study compares two methods: traditional ConvEpi access and a newer method called EpiCO, which involves puncturing coronary venous branches.
- The study included 153 patients and found that both methods had similar success rates, but ConvEpi was quicker and associated with more complications, especially significant bleeding.
- Overall, EpiCO access showed a decrease in major complications and bleeding compared to ConvEpi, suggesting it might be a safer option for patients.
Background: Targeting nonpulmonary vein triggers (NPVTs) of atrial fibrillation (AF) after pulmonary vein isolation can be challenging. NPVTs are often single ectopic beats with a surface P-wave obscured by a QRS or T-wave.
Objectives: The goal of this study was to construct an algorithm to regionalize the site of origin of NPVTs using only intracardiac bipolar electrograms from 2 linear decapolar catheters positioned in the posterolateral right atrium (along the crista terminalis with the distal bipole pair in the superior vena cava) and in the proximal coronary sinus (CS).
Article Synopsis
- Entrainment and standard pacing techniques are often ineffective in identifying critical components of ventricular tachycardia (VT) in patients with dense myocardial scarring.
- This study evaluated the effectiveness of very high-output pacing (V-HOP), which uses higher power (50 mA) to stimulate heart tissue, for locating these critical areas when standard methods failed.
- Results showed V-HOP successfully identified critical components in most patients and guided effective ablation procedures, leading to a high success rate without serious complications.
Background: There is growing interest in the possibility of discontinuing oral anticoagulation following successful catheter ablation of atrial fibrillation (AF). However, it remains unknown whether patients can accurately detect arrhythmia recurrences following ablation. We therefore sought to characterize the accuracy of pulse checking and arrhythmia symptoms for the identification of AF following ablation.
View Article and Find Full Text PDFNeuromodulation for the Treatment of Refractory Ventricular Arrhythmias.
JACC Clin Electrophysiol
February 2023
Article Synopsis
- Neuromodulation techniques such as percutaneous stellate ganglion blockade (SGB), transcutaneous magnetic stimulation (TcMS), and surgical cardiac sympathetic denervation (CSD) are being explored as treatments for patients with refractory ventricular arrhythmias (VAs).
- A retrospective study involving 34 patients revealed that these neuromodulation strategies significantly reduced the occurrence of VAs in the immediate aftermath of treatment, decreasing episodes from an average of 7 to nearly none within 24 hours.
- While most patients experienced some recurrence of VAs during follow-up, the study indicates that these neuromodulation methods are generally safe and can lead to significant short-term relief from arrhythmic episodes.
Article Synopsis
- Catheter ablation of ventricular arrhythmias from left ventricular papillary muscles can impact mitral valve function, which prompted this study to investigate the effects of lesions on mitral valve performance.
- The study analyzed 103 patients from 2015 to 2020, assessing mitral valve regurgitation before and after radiofrequency ablation using echocardiograms.
- Results showed that 99% of patients experienced no significant changes in mitral valve function post-procedure, indicating that the ablation can be performed safely without negatively affecting the mitral valve.
Article Synopsis
- The study investigates the impact of having sinus rhythm (SR) at the time of catheter ablation (CA) on long-term outcomes for patients with persistent atrial fibrillation (PersAF).
- Results show that patients who presented in SR had better freedom from atrial arrhythmias (AAs) after the procedure compared to those who presented in atrial fibrillation (AF).
- The findings suggest that achieving SR before ablation can improve overall arrhythmia outcomes and prolong the time until recurrent AF.
Background: The type 1 electrocardiographic (ECG) pattern diagnostic of Brugada syndrome (BrS) can be dynamic. Limited studies have rigorously evaluated the temporal stability of the Brugada ECG pattern.
Objective: We sought to evaluate fluctuations of the Brugada pattern in serial resting ECGs from BrS patients managed within a large health care system.
Article Synopsis
- This study examined whether using prolonged duration (PD) radiofrequency ablation (RFA) can enhance the outcomes of catheter ablation (CA) for left ventricular summit (LVS) ventricular arrhythmias (VAs).
- The research included 102 patients over four years, comparing standard RFA to PD RFA, with results showing higher procedural success and clinical outcomes with PD RFA.
- The findings suggest that PD RFA is a safe and effective approach for treating difficult LVS VAs that do not respond to standard RFA techniques.
Article Synopsis
- The study examines the role of the right ventricle (RV) in postinfarction ventricular tachycardia (VT), revealing its critical substrate in a small percentage of patients.
- Researchers reviewed 1279 patients undergoing catheter ablation for postinfarction VT and identified critical right ventricular substrate (CRVS) in 27 cases (2.1%).
- Most patients with CRVS showed significant improvements after ablation, with 80% not experiencing VT recurrence; however, 41% of the patients died within a median follow-up of 20 months.
Article Synopsis
- Autonomic neuromodulation, specifically through transcutaneous magnetic stimulation (TcMS), is being evaluated for its potential to reduce ventricular tachycardia (VT) storm episodes in patients.
- A study involving 26 patients used a double-blind, sham-controlled design to assess the safety and efficacy of TcMS targeting the left stellate ganglion, comparing it to sham stimulation.
- Results showed that, while freedom from VT in the first 24 hours didn't differ significantly between groups, the TcMS group experienced fewer VT episodes in the following 72 hours and required fewer antiarrhythmic drugs.
Article Synopsis
- The study focused on patients with left ventricular nonischemic cardiomyopathy experiencing ventricular tachycardia (VT), highlighting that the abnormal electrical activity often occurs primarily on the epicardial surface.
- Researchers found that among the 47 assessed patients, there was a significant prevalence of abnormal epicardial low-voltage areas, with the most common location being the basal inferolateral region of the left ventricle.
- The results indicated that patients who underwent ablation targeting epicardial VT had promising long-term outcomes, but those with larger endocardial low-voltage areas and more recurrent VT episodes faced higher risks of VT recurrence.
Background: Interatrial septal tachycardias (IAS-ATs) following atrial fibrillation (AF) ablation or cardiac surgery are rare, and their management is challenging.
Objective: The purpose of this study was to investigate the electrophysiological features and outcomes associated with catheter ablation of IAS-AT.
Methods: We screened 338 patients undergoing catheter ablation of ATs following AF ablation or cardiac surgery.
Objectives: This study sought to examine the impact of periprocedural acute kidney injury (AKI) in scar-related ventricular tachycardia (VT) patients undergoing radiofrequency catheter ablation (RFCA) on short- and long-term outcomes.
Background: The clinical significance of periprocedural AKI in patients with scar-related VT undergoing RFCA has not been previously investigated.
Methods: This study included 317 consecutive patients with scar-related VT undergoing RFCA (age: 64 ± 13 years, mean left ventricular ejection fraction: 33 ± 13%, 55% ischemic cardiomyopathy).
Importance: Magnetic resonance imaging (MRI) is the modality of choice for many conditions. Conditional devices and novel protocols for imaging patients with legacy cardiac implantable electronic devices (CIEDs) have increased access to MRI in patients with devices. However, the presence of abandoned leads remains an absolute contraindication.
View Article and Find Full Text PDFObjective: To evaluate the prognosis of patients with ischemic stroke according to the timing of an atrial fibrillation (AF) diagnosis, we created an inception cohort of incident stroke events and compared the risk of death between patients with stroke with (1) sinus rhythm, (2) known AF (KAF), and (3) AF diagnosed after stroke (AFDAS).
Methods: We used the Penn AF Free study to create an inception cohort of patients with incident stroke. Mortality events were identified after linkage with the National Death Index through June 30, 2017.
Atrioventricular Nodal Reentrant Tachycardia Ablation with a Power-controlled, Contact-force Catheter.
J Innov Card Rhythm Manag
November 2020
Radiofrequency catheter ablation is a safe and effective treatment option for atrioventricular nodal reentrant tachycardia (AVNRT). A nonirrigated ablation catheter used in a temperature-controlled mode is traditionally used for AVNRT ablation due to the shallow lesion depth required for successful slow-pathway ablation. In this case, a nonirrigated ablation catheter established inadequate lesions to ablate the slow pathway successfully.
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