Sanjay Dixit's research while affiliated with University of Pennsylvania and other places

Publications (330)

Article
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Background The significance of atrial fibrillation (AF) recurrences during the 90-day blanking period following catheter ablation is controversial. Studies to date examining the impact of AF recurrences during the blanking period have been limited by intermittent monitoring. We sought to test whether AF recurrences during the blanking period are as...
Article
Since the seminal observations demonstrating pulmonary veins (PVs) as the most common sites of atrial fibrillation (AF) triggers,1 PV isolation has become the standard of care for catheter ablation of AF This article is protected by copyright. All rights reserved.
Article
Background The right ventricle (RV) is uncommonly implicated in post-infarction ventricular tachycardia (VT). The prevalence and features of RV substrate participating in post-infarction VT are undefined. Objectives To characterize critical RV substrate (CRVS) involvement in patients with post-infarction VT. Methods We retrospectively reviewed 12...
Article
Objectives This study sought to explore whether prolonged duration (PD) radiofrequency ablation (RFA) from adjacent endocardial locations can improve catheter ablation (CA) outcomes of left ventricular summit (LVS) ventricular arrhythmias (Vas). Background CA of VAs originating from the LVS region can be challenging. Methods Patients undergoing C...
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Background The type 1 electrocardiographic (ECG) pattern diagnostic of the 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 healthcare...
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Background Severe endoscopically detected esophageal thermal lesions (EDELs) have been associated with higher risk of progression to atrio-esophageal fistula (AEF) following radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF). We sought to evaluate safety and feasibility of active esophageal cooling using the Attune Medical Esophage...
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Background The substrate for ventricular tachycardia (VT) in left ventricular (LV) nonischemic cardiomyopathy may be epicardial. We assessed the prevalence, location, endocardial electrograms, and VT ablation outcomes in LV nonischemic cardiomyopathy with isolated epicardial substrate. Methods Forty-seven of 531 (9%) patients with LV nonischemic c...
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Background Prescription opioids are a major contributor to the ongoing epidemic of persistent opioid use (POU). The incidence of POU among opioid-naïve patients after cardiac implantable electronic device (CIED) procedures is unknown. Methods This retrospective cohort study used data from a national administrative claims database from 2004 to 2018...
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Background The right and left pulmonary artery branches (RPA, LPA) overlie inaccessible left atrial (LA) epicardium, containing the Bachmann bundle (BB), that participate in arrhythmia pathogenesis and offer an opportunity for natural surface epicardial mapping (NSEM). Objective We sought to assess the feasibility of NSEM of BB and LA roof arrhyth...
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Background It remains unclear whether additional left atrial posterior wall isolation (LAPWI) beyond pulmonary vein reisolation (PVRI) is beneficial in atrial fibrillation (AF) patients undergoing repeat ablation. Objective We sought to assess impact of LAPWI on arrhythmia outcomes in patients undergoing repeat AF ablation. Methods All AF patient...
Article
Background Interatrial septal tachycardias (IAS-AT) following atrial fibrillation (AF) ablation or cardiac surgery are rare and their management is challenging. Objective To investigate the electrophysiologic features and outcomes associated with catheter ablation of IAS-AT. Methods We screened 338 patients undergoing catheter ablation of ATs fol...
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Background Patients with typical atrial flutter (AFL) undergoing successful cavo-tricuspid isthmus (CTI) ablation remain at risk for future development of new onset atrial fibrillation (AF). Conventional monitoring (CM) techniques have shown AF incidence rates of 18-50% in these patients. Objectives To evaluate whether continuous monitoring using...
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Importance In patients with paroxysmal atrial fibrillation (AF), rhythm control with either antiarrhythmic drugs (AADs) or catheter ablation has been associated with decreased symptoms, prevention of adverse remodeling, and improved cardiovascular outcomes. Adoption of advanced cardiovascular therapeutics, however, is often slower among patients fr...
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Objective: To evaluate the prognosis of ischemic stroke patients 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 stroke patients with a) sinus rhythm; b) known atrial fibrillation (KAF); and c) AF diagnosed after stroke (AFDAS). Metho...
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Background A substantial proportion of patients with nonischemic dilated cardiomyopathy (NICM) and ventricular tachycardia (VT) do not have scar detectable by cardiac magnetic resonance late gadolinium enhancement (LGE) imaging. In these patients, the significance of diffuse fibrosis (DF) detected with T1 mapping has not been previously investigate...
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Background: Left ventricular (LV) scar on late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) has been correlated with life-threatening arrhythmic events in patients with apparently idiopathic ventricular arrhythmias (VA). We investigated the prognostic significance of a specific LV-LGE phenotype characterized by a ring-like pattern...
Article
Introduction Oral anticoagulation(OAC) based on estimated stroke risk is recommended following catheter ablation(CA) of atrial fibrillation(AF), regardless of the extent of arrhythmia control. However, discontinuing OAC in selected patients may be safe. We sought to evaluate a strategy of OAC discontinuation following AF ablation guided by continuo...
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Transseptal access for atrial fibrillation ablation can be challenging in the presence of iatrogenically modified interatrial septum. We report the first described transseptal left atrial access for atrial fibrillation ablation in the presence of an investigational interatrial shunt device, performed in a patient with heart failure with preserved e...
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Introduction Data on the mechanisms of atrial arrhythmias (AAs) and outcomes of catheter ablation (CA) in lung transplantation (LT) patients are insufficient. We evaluated the electrophysiologic features and outcomes of CA of AAs in LT patients. Methods and Results We conducted a retrospective study of all the LT patients who underwent CA for AAs...
Article
Introduction: Long-term monitoring for atrial fibrillation (AF) is recommended in patients, who have experienced a cryptogenic stroke (CS). Clinical trials have identified AF in ~30% of patients after 3 years of continuous monitoring with insertable cardiac monitors (ICMs). Hypothesis: In a real-world analysis from a large academic healthcare syste...
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Introduction: Patients undergoing typical atrial flutter (AFL) ablation remain at risk of developing atrial fibrillation (AF). However, it is unknown whether common risk factors associated with AF occurrence, particularly race, bear out in this population. Hypothesis: We sought to compare the occurrence of new AF in male veteran African-American (A...
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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...
Article
Objectives This study sought to address whether technological innovations such as contact force sensing (CFS) can improve acute and long-term ablation outcomes of left ventricular papillary muscle (LV PAP) ventricular arrhythmias (VAs). Background Catheter ablation of LV PAP VAs has been less efficacious than another focal VAs. It remains unclear...
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Background Early studies suggest that coronavirus disease 2019 (COVID-19) is associated with a high incidence of cardiac arrhythmias. SARS-CoV-2 infection may cause injury to cardiac myocytes and increase arrhythmia risk. Objective To evaluate the risk of cardiac arrest and arrhythmias including incident atrial fibrillation (AF), bradyarrhythmias,...
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Background Electrical posterior wall isolation (PWI) is increasingly utilized for the treatment of patients with atrial fibrillation (AF). Little data exists on the durability of PWI using current technology. Objective To characterize the frequency and location of posterior wall reconnection at the time of repeat catheter ablation for AF. Methods...
Article
Objectives This study investigated the impact of the type of catheter irrigant used during delivery of radiofrequency ablation. Background The use of half-normal saline (HNS) as an irrigant has been suggested as a method for increasing ablation lesion size but has not been rigorously studied in the beating heart or the use of a low-flow irrigation...
Article
Background 12-lead electrocardiogram (ECG) criteria have been developed to identify idiopathic ventricular arrhythmias (VAs) from the left ventricular (LV) papillary muscles (PAPs), but accurate localization remains a challenge. Objective To develop ECG criteria for accurate localization of LV PAP VAs utilizing lead V1 exclusively. Methods Consec...
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Background The left ventricular apex (LVA) is a well-described source of ventricular arrhythmias (VAs) in patients with coronary artery disease (CAD) and history of apical infarction but is a rare source of VA in the absence of CAD. Objectives This study aimed to characterize the incidence, clinical characteristics, and electrocardiographic and el...
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Introduction In patients with non‐ischemic cardiomyopathy (NICM) little is known about the clinical impact of catheter ablation (CA) of septal ventricular tachycardia (VT) resulting in collateral injury of the conduction system (CICS). Methods and results 95 consecutive patients with NICM underwent CA of septal VT. Outcomes in patients with no bas...
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Objectives: This study describes the technique and outcomes of atrial fibrillation (AF) ablation via a superior approach in patients with interrupted or absent inferior vena cavas (IVCs). Background: In patients with interrupted or absent IVCs, transseptal access cannot be obtained via standard femoral venous access. In these patients, alternati...
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Background Post-operative bradycardia can complicate orthotopic heart transplantation (OHT). Previous studies suggested donor age, surgical technique as possible risk factors. However, risk factors in the era of bicaval anastomosis have not been elucidated. Objectives We sought to examine the association between donor/recipient characteristics wit...
Article
Background - Data characterizing structural changes of arrhythmogenic right ventricular cardiomyopathy (ARVC) are limited. Methods - Patients presenting with left bundle branch block ventricular tachycardia (VT) in the setting of ARVC with procedures separated by at least 9 months were included. Results - Nineteen consecutive patients (84% males; m...
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Background: We have previously demonstrated the feasibility of a nurse-led risk factor modification (RFM) program for improving weight loss and obstructive sleep apnea (OSA) care among atrial fibrillation (AF) patients. Objective: We now report its impact on arrhythmia outcomes in a subgroup of patients undergoing catheter ablation. Methods: P...
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Objectives This study investigated the prevalence and prognostic significance of concealed myocardial abnormalities identified by cardiac magnetic resonance (CMR) imaging in patients with apparently idiopathic premature ventricular contractions (PVCs). Background The role of CMR imaging in patients with frequent PVCs and otherwise negative diagnos...
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Objectives: This study sought to evaluate the prevalence, mapping features, and ablation outcomes of non-scar-related ventricular tachycardia (NonScar-VT) and Purkinje-related VT (Purkinje-VT) in patients with structural heart disease. Background: VT in structural heart disease is typically associated with scar-related myocardial re-entry. NonSc...
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Objectives: This study sought to examine clinical characteristics of procedural and long-term outcomes in patients undergoing catheter ablation (CA) of outflow tract ventricular arrhythmias (OT-VAs) over 16 years. Background: CA is an effective treatment strategy for OT-VAs. Methods: Patients undergoing CA for OT-VAs from 1999 to 2015 were div...
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Objective: This study sought to investigate incidence of left atrial appendage (LAA) triggers of atrial fibrillation (AF) and/or organized atrial tachycardias (OAT) in patients undergoing AF ablation and to evaluate outcomes after ablation. Background: Although LAA isolation is being increasingly performed during AF ablation, the true incidence...
Conference Paper
Background The right ventricle (RV) is uncommonly implicated in post-infarction ventricular tachycardia (PIVT). The prevalence and features of RV substrate participating in PIVT are undefined. Objectives To characterize critical RV substrate (CRVS) involvement in PIVT. Methods We retrospectively reviewed 1065 patients with PIVT undergoing cathete...
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Objectives: This study sought to compare efficacy and safety of the septal mitral isthmus line (SMIL) with that of the lateral mitral isthmus line (LMIL) for treatment of mitral annular flutter (MAF). Background: MAF is the most common left atrial macro-re-entrant organized atrial tachycardia (OAT) occurring after catheter ablation of atrial fib...
Article
Background: Catheter ablation (CA) of idiopathic premature ventricular complexes (PVCs) is typically guided by both activation and pace-mapping, with ablation ideally delivered at the site of earliest local activation. However, activation mapping requires sufficient intra-procedural quantity of PVCs. This study aimed to investigate the outcome of...
Conference Paper
Left atrial voltage maps are routinely acquired during electroanatomic mapping in patients undergoing catheter ablation for atrial fibrillation (AF). For patients, who have prior catheter ablation when they are in sinus rhythm (SR), the voltage map can be used to identify low voltage areas (LVAs) using a threshold of 0.2 - 0.45 mV. However, such a...
Article
Background: There has been increasing awareness of the 3-dimensional nature of ventricular tachycardia (VT) circuits. VT circuits in patients with ischemic cardiomyopathies (ICM) and non-ICM (NICM) may differ in this regard. Methods: Among patients with structural heart disease and at least 1 hemodynamically tolerated VT undergoing ablation, we...
Article
Background: The slow pathway region (SPR) is commonly targeted during ablation of atrioventricular nodal reentrant tachycardia. However, its role in idiopathic ventricular arrhythmias (IVAs) remains unknown. Objective: The purpose of this study was to describe the electrocardiographic and electrophysiological characteristics of IVAs that were su...
Article
Objectives This study sought to determine the impact of repeat catheter ablation (CA) prior to hospital discharge based on inducibility of clinical ventricular tachycardia (VT) during noninvasive programmed ventricular stimulation (NIPS). Background Inducibility of clinical VT during NIPS performed several days after CA identifies patients at high...
Article
Objectives: This study sought to assess the performance of established risk models in predicting outcomes after catheter ablation (CA) in patients with nonischemic dilated cardiomyopathy (NIDCM) and ventricular tachycardia (VT). Background: A correct pre-procedural risk stratification of patients with NIDCM and VT undergoing CA is crucial. The p...
Article
Objectives This study sought to characterize ventricular arrhythmia (VA) ablated from the basal inferoseptal left ventricular endocardium (BIS-LVe) and identify electrocardiographic characteristics to differentiate from inferobasal crux (IBC) VA. Background The inferior basal septum is an uncommon source of idiopathic VAs, which can arise from its...
Article
Left atrial voltage maps are routinely acquired during electroanatomic mapping in patients undergoing catheter ablation for atrial fibrillation (AF). For patients, who have prior catheter ablation when they are in sinus rhythm (SR), the voltage map can be used to identify low voltage areas (LVAs) using a threshold of 0.2 - 0.45 mV. However, such a...
Article
Introduction Non‐pulmonary vein (PV) triggers of atrial fibrillation (AF) are targets for ablation but their localization remains challenging. This study’s aim was to describe P‐wave (PW) morphologic characteristics and intraatrial activation patterns and timing from multipolar coronary sinus (CS) and crista terminalis (CT) catheters that localize...
Article
Background Outcomes of ventricular tachycardia (VT) ablation in structural heart disease have been reported to differ by sex. Whether this is due to differences in the underlying arrhythmogenic substrates among patients with nonischemic cardiomyopathy (NICM) remains unclear. Objective The purpose of this study was to compare the characteristics of...
Article
Aims: Catheter ablation of outflow tract ventricular arrhythmias (OTVAs) with the earliest activation within the coronary venous system (CVS) can be challenging. When ablation from the CVS is not feasible or ineffective, an approach from anatomically adjacent site(s) can be considered. We report the outcomes of an anatomical approach for OTVAs lin...
Article
Full-text available
Idiopathic outflow tract ventricular arrhythmias (VAs) occur typically in patients without structural heart disease. They are often symptomatic and can sometimes lead to left ventricular systolic dysfunction. Both activation and pace mapping are utilised for successful ablation of these arrhythmias. Pace mapping is particularly helpful when the VA...