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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. The provocation protocol included step 1, identification of spontaneous non-PV triggers after cardioversion of AF and/or during sinus rhythm; step 2, isoproterenol infusion (3, 6, 12, and 20-30 µg/min); and step 3, atrial burst pacing to induce AF followed by cardioversion during residual or low-dose isoproterenol infusion or induce focal atrial tachycardia. Non-PV triggers were defined as non-PV ectopic beats triggering AF or sustained focal atrial tachycardia. RESULTS: Of 1,372 patients included, 883 (64.4%) underwent the complete stepwise provocation protocol with isoproterenol infusion and burst pacing, 334 (24.3%) isoproterenol infusion only, 77 (5.6%) burst pacing only, and 78 (5.7%) no provocative maneuvers (only step 1). Overall, 161 non-PV triggers were found in 135 (9.8%) patients. Of these, 51 (31.7%) non-PV triggers occurred spontaneously, and the remaining 110 (68.3%) required provocative maneuvers for induction. Among those receiving the complete stepwise provocation protocol, there was a 2.2-fold increase in the number of patients with non-PV triggers after isoproterenol infusion, and the addition of burst pacing after isoproterenol infusion led to a total increase of 3.6-fold with the complete stepwise provocation protocol. CONCLUSIONS: The majority of non-PV triggers require provocative maneuvers for induction. A stepwise provocation protocol consisting of isoproterenol infusion followed by burst pacing identifies a 3.6-fold higher number of patients with non-PV triggers.
Subject(s)
Atrial Fibrillation , Catheter Ablation , Isoproterenol , Humans , Atrial Fibrillation/surgery , Female , Male , Middle Aged , Catheter Ablation/adverse effects , Catheter Ablation/methods , Isoproterenol/administration & dosage , Isoproterenol/therapeutic use , Aged , Pulmonary Veins/surgery , Electric Countershock , Retrospective StudiesABSTRACT
INTRODUCTION: Identifying the origin of nonpulmonary vein atrial fibrillation (AF) triggers (NPVTs) after pulmonary vein isolation (PVI) can be challenging. We aimed to determine if noninvasive electrocardiographic imaging (ECGi) could localize pacing from common NPVT sites. ECGi combines measured body surface potentials with heart-torso geometry acquired from computed tomography (CT) to generate an activation map. METHODS: In 12 patients with AF undergoing first time ablation, the ECGi vest was fitted for preprocedural CT scan and worn during the procedure. After PVI, we performed steady-state pacing from 15 typical anatomic NPVT sites at a cycle length of 700-800 ms. We co-registered the invasive anatomic map with the CT-based ECGi epicardial activation map to compare ECGi predicted to true pacing origin. RESULTS: In the study cohort (67% male, 58% persistent AF, and 67% with left atrial dilation), 148 (82%) pacing sites had both capture and adequate anatomy acquired from the three-dimensional mapping system to co-register with ECGi activation map. Median distance between true pacing sites and point of earliest epicardial activation derived from the ECGi maps for all sites was 17 mm (interquartile range, 10-22 mm). Assuming paced sites treated as regions with a radius of 2.5 cm, the earliest activation site on ECGi map falls within the region with 94% accuracy. CONCLUSION: ECGi can approximate the origin of paced beats from common NPVT sites to within a median distance of 17 mm. A rapidly identified region may then be the focus of more detailed catheter-based mapping techniques to facilitate successful localization and ablation of NPVTs.
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BACKGROUND: Epicardial (Epi) access is commonly required during ventricular tachycardia ablation. Conventional Epi (ConvEpi) access targets a "dry" pericardial space presenting technical challenges and risk of complications. Recently, intentional puncture of coronary venous branches with Epi carbon dioxide insufflation (EpiCO2) has been described as a technique to improve Epi access. The safety of this technique relative to conventional methods remains unproven. OBJECTIVES: The authors sought to compare the feasibility and safety of EpiCO2 to ConvEpi access. METHODS: All patients at a high-volume center undergoing Epi access between January 2021 and December 2023 were included and grouped according to ConvEpi or EpiCO2 approach. Access technique was according to the discretion of the operator. RESULTS: Epi access was attempted in 153 cases by 17 different operators (80 ConvEpi vs 73 EpiCO2). There was no difference in success rate whether the ConvEpi or EpiCO2 approach was used (76 [95%] cases vs 67 [91.8%] cases; P = 0.4). Total Epi access time was shorter in the ConvEpi group compared with the EpiCO2 group (16.3 ± 11.6 minutes vs 26.9 ± 12.7 minutes; P < 0.001), though the total procedure duration was similar. Major Epi access-related complications occurred in only the ConvEpi group (6 [7.5%] ConvEpi vs 0 [0%] EpiCo2; P = 0.02). Bleeding ≥80 mL was more frequently observed following ConvEpi access (14 [17.5%] cases vs 4 [5.5%] cases; P = 0.02). After adjusting for age, repeat Epi access, and antithrombotic therapy, EpiCO2 was associated with a reduction in bleeding ≥80 mL (OR: 0.27; 95% CI: 0.08-0.89; P = 0.03). CONCLUSIONS: EpiCO2 access is associated with lower rates of major complication and bleeding when compared with ConvEpi access.
Subject(s)
Carbon Dioxide , Catheter Ablation , Insufflation , Pericardium , Tachycardia, Ventricular , Humans , Male , Female , Middle Aged , Insufflation/methods , Insufflation/adverse effects , Pericardium/surgery , Tachycardia, Ventricular/surgery , Catheter Ablation/methods , Catheter Ablation/adverse effects , Aged , Retrospective Studies , Feasibility StudiesABSTRACT
BACKGROUND: Although the epicardial predominance of substrate abnormalities has been well demonstrated in early stages of arrhythmogenic right ventricular cardiomyopathy (ARVC), endocardial (ENDO) ablation may suffice to eliminate ventricular tachycardia (VT) in some patients. OBJECTIVES: This study aimed to report the long-term outcomes of ENDO-only ablation in ARVC patients and factors that predict VT-free survival. METHODS: We included consecutive patients with Task Force Criteria diagnosis of ARVC undergoing a first ENDO-only VT ablation between 1998 and 2020. Ablation was predominantly guided by activation/entrainment mapping for mappable VTs and pace mapping/targeting abnormal electrograms for unmappable VTs. The primary endpoint was freedom from any recurrent sustained VT after the last ENDO-only ablation. RESULTS: Seventy-four ARVC patients underwent ENDO-only VT ablation. VT noninducibility was achieved in 49 (66%) patients. During median follow-up of 6.6 years (Q1-Q3: 3.4-11.2 years), 40 (54.1%) patients remained free from any VT recurrence with rare VT ≤2 episodes in additional 12.2%. Among patients with noninducibility, VT-free survival was 75.5% during long-term follow-up. In multivariable analysis, >45 y of age at diagnosis (HR: 0.41; 95% CI: 0.17-0.98) and VT noninducibility (HR: 0.36; 95% CI: 0.16-0.80) were predictors of VT-free survival. CONCLUSIONS: Long-term VT-free survival can be achieved in over half of ARVC patients following ENDO-only VT ablation, increasing to over 75% if VT noninducibility is achieved. Our results support consideration of a stepwise ENDO-only approach before proceeding to epicardial ablation if VT noninducibility can be achieved particularly in older patients.
Subject(s)
Arrhythmogenic Right Ventricular Dysplasia , Catheter Ablation , Endocardium , Tachycardia, Ventricular , Humans , Male , Arrhythmogenic Right Ventricular Dysplasia/surgery , Arrhythmogenic Right Ventricular Dysplasia/physiopathology , Arrhythmogenic Right Ventricular Dysplasia/complications , Female , Catheter Ablation/methods , Catheter Ablation/statistics & numerical data , Tachycardia, Ventricular/surgery , Tachycardia, Ventricular/physiopathology , Middle Aged , Adult , Endocardium/surgery , Endocardium/physiopathology , Treatment Outcome , Recurrence , Retrospective StudiesABSTRACT
BACKGROUND: Substantial data support a heritable basis for supraventricular tachycardias, but the genetic determinants and molecular mechanisms of these arrhythmias are poorly understood. We sought to identify genetic loci associated with atrioventricular nodal reentrant tachycardia (AVNRT) and atrioventricular accessory pathways or atrioventricular reciprocating tachycardia (AVAPs/AVRT). METHODS: We performed multiancestry meta-analyses of genome-wide association studies to identify genetic loci for AVNRT (4 studies) and AVAP/AVRT (7 studies). We assessed evidence supporting the potential causal effects of candidate genes by analyzing relations between associated variants and cardiac gene expression, performing transcriptome-wide analyses, and examining prior genome-wide association studies. RESULTS: Analyses comprised 2384 AVNRT cases and 106â 489 referents, and 2811 AVAP/AVRT cases and 1,483â 093 referents. We identified 2 significant loci for AVNRT, which implicate NKX2-5 and TTN as disease susceptibility genes. A transcriptome-wide association analysis supported an association between reduced predicted cardiac expression of NKX2-5 and AVNRT. We identified 3 significant loci for AVAP/AVRT, which implicate SCN5A, SCN10A, and TTN/CCDC141. Variant associations at several loci have been previously reported for cardiac phenotypes, including atrial fibrillation, stroke, Brugada syndrome, and electrocardiographic intervals. CONCLUSIONS: Our findings highlight gene regions associated with ion channel function (AVAP/AVRT), as well as cardiac development and the sarcomere (AVAP/AVRT and AVNRT) as important potential effectors of supraventricular tachycardia susceptibility.
Subject(s)
Genome-Wide Association Study , Tachycardia, Supraventricular , Humans , Tachycardia, Supraventricular/genetics , Genetic Predisposition to Disease , Tachycardia, Atrioventricular Nodal Reentry/genetics , Polymorphism, Single Nucleotide , Connectin/genetics , TranscriptomeABSTRACT
Background: Long-term rhythm monitoring to detect atrial fibrillation (AF) following a cryptogenic stroke (CS) is well established. However, the burden of organized atrial arrhythmias in this population is not well defined. Objective: The purpose of this study was to assess the incidence and risk factors for organized atrial arrhythmias in patients with CS. Methods: We evaluated all patients with CS who received an insertable cardiac monitor (ICM) between October 2014 and April 2020. All ICM transmissions categorized as AF, tachycardia, or bradycardia were reviewed. We evaluated the time to detection of organized AF and the combination of either organized atrial arrhythmia or AF. Results: A total of 195 CS patients with ICMs were included (51% men; mean age 66 ± 12 years; mean CHA2DS2-VASC score 4.6). Over mean follow-up of 18.9 ± 11.2 months, organized atrial arrhythmias lasting ≥30 seconds were detected in 45 patients (23%), of whom 62% did not have AF. Seventeen patients had both organized atrial arrhythmia and AF, and another 21 patients had AF only. Compared to those with normal left atrial size, patients with left atrial enlargement had a higher adjusted risk for development of atrial arrhythmias (mild left atrial enlargement: hazard ratio 1.99; 95% confidence interval 1.06-3.75; moderate/severe left atrial enlargement: hazard ratio 3.06; 95% confidence interval 1.58-5.92). Conclusion: Organized atrial arrhythmias lasting ≥30 seconds are detected in nearly one-fourth of CS patients. Two-thirds of these patients did not have AF. Further studies are required to evaluate the impact of organized atrial arrhythmias on recurrent stroke risk.
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BACKGROUND: Targeting non-pulmonary vein triggers (NPVTs) after pulmonary vein isolation may reduce atrial fibrillation (AF) recurrence. Isoproterenol infusion and cardioversion of spontaneous or induced AF can provoke NPVTs but typically require vasopressor support and increased procedural time. OBJECTIVE: The purpose of this study was to identify risk factors for the presence of NPVTs and create a risk score to identify higher-risk subgroups. METHODS: Using the AF ablation registry at the Hospital of the University of Pennsylvania, we included consecutive patients who underwent AF ablation between January 2021 and December 2022. We excluded patients who did not receive NPVT provocation testing after failing to demonstrate spontaneous NPVTs. NPVTs were defined as non-pulmonary vein ectopic beats triggering AF or focal atrial tachycardia. We used risk factors associated with NPVTs with P <.1 in multivariable logistic regression model to create a risk score in a randomly split derivation set (80%) and tested its predictive accuracy in the validation set (20%). RESULTS: In 1530 AF ablations included, NPVTs were observed in 235 (15.4%). In the derivation set, female sex (odds ratio [OR] 1.40; 95% confidence interval [CI] 0.96-2.03; P = .080), sinus node dysfunction (OR 1.67; 95% CI 0.98-2.87; P = .060), previous AF ablation (OR 2.50; 95% CI 1.70-3.65; P <.001), and left atrial scar (OR 2.90; 95% CI 1.94-4.36; P <.001) were risk factors associated with NPVTs. The risk score created from these risk factors (PRE2SSS2 score; [PRE]vious ablation: 2 points, female [S]ex: 1 point, [S]inus node dysfunction: 1 point, left atrial [S]car: 2 points) had good predictive accuracy in the validation cohort (area under the receiver operating characteristic curve 0.728; 95% CI 0.648-0.807). CONCLUSION: A risk score incorporating predictors for NPVTs may allow provocation of triggers to be performed in patients with greatest expected yield.
Subject(s)
Atrial Fibrillation , Catheter Ablation , Pulmonary Veins , Humans , Atrial Fibrillation/physiopathology , Atrial Fibrillation/etiology , Atrial Fibrillation/diagnosis , Female , Male , Pulmonary Veins/surgery , Middle Aged , Catheter Ablation/methods , Catheter Ablation/adverse effects , Risk Factors , Risk Assessment/methods , Retrospective Studies , Aged , Registries , Heart Conduction System/physiopathology , Recurrence , Follow-Up StudiesSubject(s)
Carbon Dioxide , Insufflation , Pericardium , Insufflation/methods , Tissue Adhesions , Humans , Animals , Catheter Ablation/methodsABSTRACT
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. METHODS: This prospective cohort study included patients at the Hospital of the University of Pennsylvania with an insertable cardiac monitor (ICM) treated with catheter ablation for AF who recorded the results from minimum twice daily pulse checks and additionally with arrhythmia symptoms into a diary for 2 months following their procedure. Accuracy of this self-assessment protocol was determined by comparison to ICM-detected AF. RESULTS: A total of 55 patients (age 69 ± 8 years, 30 (55%) male, CHA2DS2VASc score 3.2 ± 1. 5) were included. Patients recorded a total of 5911 pulse checks, and there were 280 episodes of ICM-documented AF among 26 patients with an average duration of 2.5 ± 3.3 h. Among 362 episodes of patient-suspected AF, 134 correlated with ICM-identified AF (37% true positive rate). Of the 5549 pulse checks that did not identify AF, 196 correlated with ICM-identified AF (4% false negative rate). Twice daily pulse checking had a sensitivity of 47% and a specificity of 96% for identifying each episode of AF. CONCLUSIONS: Our data indicate that a strategy of pulse checks and symptom assessment is insufficient to identify all episodes of AF in many patients following catheter ablation.
Subject(s)
Atrial Fibrillation , Catheter Ablation , Humans , Male , Middle Aged , Aged , Female , Atrial Fibrillation/diagnosis , Atrial Fibrillation/surgery , Prospective Studies , Electrocardiography, Ambulatory/methods , Heart Rate , Catheter Ablation/methodsABSTRACT
BACKGROUND: The use of a multi-electrode Optrell mapping catheter during ventricular tachycardia (VT) or premature ventricular complex (PVC) ablation procedures has not been widely reported. OBJECTIVES: We aim to describe the feasibility and safety of using the Optrell multipolar mapping catheter (MPMC) to guide catheter ablation of VT and PVCs. METHODS: We conducted a single-center, retrospective evaluation of patients who underwent VT or PVC ablation between June and November 2022 utilizing the MPMC. RESULTS: A total of 20 patients met the inclusion criteria (13 VT and 7 PVC ablations, 80% male, 61 ± 15 years). High-density mapping was performed in the VT procedures with median 2753 points [IQR 1471-17,024] collected in the endocardium and 12,830 points [IQR 2319-30,010] in the epicardium. Operators noted challenges in manipulation of the MPMC in trabeculated endocardial regions or near valve apparatus. Late potentials (LPs) were detected in 11 cases, 7 of which had evidence of isochronal crowding demonstrated during late annotation mapping. Two patients who also underwent entrainment mapping had critical circuitry confirmed in regions of isochronal crowding. In the PVC group, high-density voltage and activation mapping was performed with a median 1058 points [IQR 534-3582] collected in the endocardium. CONCLUSIONS: This novel MPMC can be used safely and effectively to create high-density maps in LV endocardium or epicardium. Limitations of the catheter include a longer wait time for matrix formation prior to starting point collection and challenges in manipulation in certain regions.
Subject(s)
Catheter Ablation , Tachycardia, Ventricular , Ventricular Premature Complexes , Humans , Male , Female , Retrospective Studies , Tachycardia, Ventricular/diagnostic imaging , Tachycardia, Ventricular/surgery , Ventricular Premature Complexes/surgery , Electrodes , Catheters , Catheter Ablation/methodsABSTRACT
BACKGROUND: Pectoral nerve (PECs) blocks are established regional anesthesia techniques that can provide analgesia to the anterior chest wall. Although commonly performed preoperatively by anesthesiologists, the feasibility of electrophysiologist-performed PECs blocks from within cardiac implantable electronic device (CIED) pockets at the time of implantation has not been established. The objective of this study is to assess the feasibility of routine PECs blocks performed by the electrophysiologist from within the exposed device pocket at the time of CIED procedures. METHODS: Patients undergoing CIED procedures underwent a PECs I block (15 cc of 1% lidocaine/0.25% bupivacaine) injected between the pectoralis major and minor muscles guided by ultrasound placed in the device pocket, or PECs II block, which included a second injection (15 cc) between pectoralis minor and serratus anterior muscles. Postoperatively, pain was assessed on a numeric scale (0-10) at 1, 2, 4, and 24 h, and 2 weeks after the procedure. RESULTS: Among 20 patients (age 65 ± 16 years, 70% male, 55% with history of chronic pain), PECs I (75%) and PECs II (25%) blocks were performed. The procedures were de novo implantation (n = 17) or device revision (n = 3). The average pain score in the first 4 h was 0.4 ± 0.8 and 0.3 ± 0.6 at 24 h after the procedure. During the 24-h postoperative period, 4 patients received opioids. Two patients were discharged with opioids for pain unrelated to the procedure. CONCLUSIONS: Intraoperative PECs blocks can be feasibly performed from within an exposed pocket at the time of CIED procedures with minimal postoperative pain.
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Background: Ictal-associated bradyarrhythmia or asystole can be a manifestation of malignant seizure syndromes. In patients with ictal-associated hypervagotonia and asystole, cardioneuroablation may provide a promising alternative to permanent pacemaker implantation. Case summary: We present a case of a 47-year-old female with a 1.5-year history of ongoing uncontrolled seizures with multiple semiologies despite multiple antiepileptic drugs who had episodes of symptomatic severe sinus bradycardia (15-30 b.p.m.) and sinus pauses (15-16â s). She underwent a successful cardioneuroablation for ictal-induced asystole with complete resolution of bradyarrhythmias. Discussion: This case highlights the utility of cardioneuroablation in patient with ictal-induced cardiac bradyarrhythmia and asystole. Cardioneuroablation may be an approach to avoid permanent pacemakers in this population.
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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). METHODS: After pulmonary vein isolation in 42 patients with AF, pacing from 15 typical anatomic NPVT sites was conducted. For each pacing site, the electrogram activation sequence was analyzed from the CS catheter (simultaneous/chevron/inverse chevron/distal-proximal/proximal-distal) and activation time (ie, CSCTAT) between the earliest electrograms from the 2 decapolar catheters was measured referencing the earliest CS electrogram; a negative CSCTAT value indicates the crista terminalis catheter electrogram was earlier, and a positive CSCTAT value indicates the CS catheter electrogram was earlier. A regionalization algorithm with high predictive value was defined and tested in a validation cohort with AF NPVTs localized with electroanatomic mapping. RESULTS: In the study patient cohort (71% male; 43% with persistent AF, 52% with left atrial dilation), the algorithm grouped with high precision (positive predictive value 81%-99%, specificity 94%-100%, and sensitivity 30%-94%) the 15 distinct pacing sites into 9 clinically useful regions. Algorithm testing in a 98 patient validation cohort showed predictive accuracy of 91%. CONCLUSIONS: An algorithm defined by the activation sequence and timing of electrograms from 2 linear multipolar catheters provided accurate regionalization of AF NPVTs to guide focused detailed mapping.
Subject(s)
Atrial Fibrillation , Vena Cava, Superior , Humans , Male , Female , Atrial Fibrillation/diagnosis , Atrial Fibrillation/surgery , Heart Atria , Catheters , AlgorithmsABSTRACT
BACKGROUND: Entrainment and pace mapping are used to identify critical components (CCs) of ventricular tachycardia (VT) circuits. In patients with dense myocardial scarring, VT circuits may elude capture at standard high pacing outputs (up to 10 mA at a 2-millisecond pulse width). OBJECTIVES: The purpose of this study was to assess the utility of very high-output pacing (V-HOP, 50 mA at 2 milliseconds) for identifying CCs of VT circuits after standard high pacing output failed to elicit capture in densely scarred myocardial tissue. METHODS: Our standard VT ablation approach included electroanatomic mapping for substrate characterization and entrainment and/or pace mapping to identify CCs of VT circuits. Patients that required V-HOP to capture sites of interest comprised the study cohort. Ablation endpoints were VT termination and noninducibility. RESULTS: Twenty-five patients (71 ± 10 years of age, all males) undergoing 26 VT ablations met the inclusion criteria. The mean left ventricular ejection fraction was 30% ± 14%, and 85% had ischemic cardiomyopathy. V-HOP was used to successfully entrain VT in 17 patients, yielding central isthmus sites in 10 and entrance/exit sites in 4. VT terminated with radiofrequency ablation at these sites in 15 patients. In 9 patients, V-HOP identified scar locations with a delayed exit. Acute procedural success was achieved in 24 patients without any adverse events. Over a follow-up period of 16 ± 21 months, 2 patients experienced VT recurrence requiring repeat ablation during which the same location was targeted successfully in 1 patient. CONCLUSIONS: In VT patients with a dense scar that is traditionally inexcitable, V-HOP can identify CCs of the re-entrant circuit and guide successful ablation.
Subject(s)
Myocardial Ischemia , Tachycardia, Ventricular , Male , Humans , Cicatrix , Stroke Volume , Ventricular Function, Left , Tachycardia, Ventricular/diagnosis , Tachycardia, Ventricular/surgeryABSTRACT
BACKGROUND: Although efficacious, catheter ablation (CA) of ventricular arrhythmias (VAs) originating from left ventricular (LV) papillary muscles (PAPs) has the potential to affect mitral valve (MV) function. OBJECTIVES: The aim of this study was to determine whether lesions delivered during CA of VAs from LV PAPs affected MV function. METHODS: Consecutive patients undergoing CA of LV PAP VAs from January 2015 to December 2020 in whom both preprocedural and postprocedural transthoracic echocardiography was performed were included. Radiofrequency ablation was performed with an irrigated-tip catheter with or without contact force sensing and intracardiac echocardiographic guidance. The PAPs were delineated into segments: tip, body, and base. Pre- and post-CA transthoracic echocardiograms were reviewed to assess MV regurgitation, which was graded 0 (none), 1 (mild), 2 (moderate), or 3 (severe). A change of ≥2 grades from baseline was considered significant. RESULTS: A total of 103 patients (mean age 63 ± 15 years, 78% men) were included. VAs were ablated from the anterolateral PAP in 35% (n = 36), posteromedial PAP in 55% (n = 57), and both PAPs in 10% (n = 10). Lesion distribution was as follows: PAP tip in 52 (50%), PAP base in 34 (33%), PAP body in 13 (13%), and entire PAP in 4 (4%). The mean number of lesions delivered was 16 ± 13 (median 14). Of 103 patients, 102 (99%) showed no change in MV function. CONCLUSIONS: Using intracardiac echocardiographic guidance, lesions can be safely delivered on various aspects of this structure without adverse impact on MV function.