Real-world data of radiofrequency catheter ablation in paroxysmal atrial fibrillation: Short- and long-term clinical outcomes from the prospective multicenter REAL-AF Registry.

BACKGROUND: The safety and long-term efficacy of radiofrequency (RF) catheter ablation (CA) of paroxysmal atrial fibrillation (PAF) has been well established. Contemporary techniques to optimize ablation delivery, reduce fluoroscopy use, and improve clinical outcomes have been developed. OBJECTIVE: The purpose of this study was to assess the contemporary real-world practice approach and short and long-term outcomes of RF CA for PAF through a prospective multicenter registry. METHODS: Using the REAL-AF (Real-world Experience of Catheter Ablation for the Treatment of Symptomatic Paroxysmal and Persistent Atrial Fibrillation; ClincalTrials.gov Identifier: NCT04088071) Registry, patients undergoing RF CA to treat PAF across 42 high-volume institutions and 79 experienced operators were evaluated. The procedures were performed using zero or reduced fluoroscopy, contact force sensing catheters, wide area circumferential ablation, and ablation index as a guide with a target of 380-420 for posterior and 500-550 for anterior lesions. The primary efficacy outcome was freedom from all-atrial arrhythmia recurrence at 12 months. RESULTS: A total of 2470 patients undergoing CA from January 2018 to December 2022 were included. Mean age was 65.2 ±11.14 years, and 44% were female. Most procedures were performed without fluoroscopy (71.5%), with average procedural and total RF times of 95.4 ± 41.7 minutes and 22.1±11.8 minutes, respectively. At 1-year follow-up, freedom from all-atrial arrhythmias was 81.6% with 89.7% of these patients off antiarrhythmic drugs. No significant difference was identified comparing pulmonary vein isolation vs pulmonary vein isolation plus ablation approaches. The complication rate was 1.9%. CONCLUSION: Refinement of RF CA to treat PAF using contemporary tools, standardized protocols, and electrophysiology laboratory workflows resulted in excellent short- and long-term clinical outcomes.

Design and characteristics of the prophylactic intra-operative ventricular arrhythmia ablation in high-risk LVAD candidates (PIVATAL) trial.

BACKGROUND: The use of a Left Ventricular Assist Device (LVAD) in patients with advanced heart failure refractory to optimal medical management has progressed steadily over the past two decades. Data have demonstrated reduced LVAD efficacy, worse clinical outcome, and higher mortality for patients who experience significant ventricular tachyarrhythmia (VTA). We hypothesize that a novel prophylactic intra-operative VTA ablation protocol at the time of LVAD implantation may reduce the recurrent VTA and adverse events postimplant. METHODS: We designed a prospective, multicenter, open-label, randomized-controlled clinical trial enrolling 100 patients who are LVAD candidates with a history of VTA in the previous 5 years. Enrolled patients will be randomized in a 1:1 fashion to intra-operative VTA ablation (n = 50) versus conventional medical management (n = 50) with LVAD implant. Arrhythmia outcomes data will be captured by an implantable cardioverter defibrillator (ICD) to monitor VTA events, with a uniform ICD programming protocol. Patients will be followed prospectively over a mean of 18 months (with a minimum of 9 months) after LVAD implantation to evaluate recurrent VTA, adverse events, and procedural outcomes. Secondary endpoints include right heart function/hemodynamics, healthcare utilization, and quality of life. CONCLUSION: The primary aim of this first-ever randomized trial is to assess the efficacy of intra-operative ablation during LVAD surgery in reducing VTA recurrence and improving clinical outcomes for patients with a history of VTA.

Prophylactic Colchicine After Radiofrequency Ablation of Atrial Fibrillation: The PAPERS Study.

BACKGROUND: Pericarditis is common after radiofrequency ablation for atrial fibrillation (AF). OBJECTIVES: Study investigators hypothesized an empirical post-AF ablation treatment protocol with colchicine may reduce the incidence and severity of pericarditis. PAPERS (Post-Ablation PEricarditis Reduction Study) aimed to quantify the risks and benefits associated with prophylactic use of colchicine to prevent pericarditis following AF ablation. METHODS: PAPERS is a multicenter, prospective, randomized controlled study. Patients were randomized on the day of the procedure to receive no postprocedure prophylaxis (group A; standard of care arm) or colchicine 0.6 mg orally twice daily for 7 days starting immediately post-procedure (group B; study arm). All participants underwent a follow-up survey at 14 days postoperatively. The primary endpoint was the development of clinical pericarditis within 2 weeks following ablation. Secondary outcomes included the incidence of pericarditis by ablation type and medical therapy. RESULTS: Among 139 patients enrolled, 66 were randomized to standard of care (group A), and 73 patients were randomized to the colchicine arm (group B). The primary outcome of clinical pericarditis was reached in 7 of 66 (10.6%) patients in group A and in 7 of 73 (9.6%) patients in group B (P = 0.84). The rate of gastrointestinal discomfort was 10 of 66 (15%) in group A and 34 of 73 (47%) in group B (P < 0.001). There was an increased incidence of pericarditis in patients who underwent cavotricuspid isthmus ablation (17 of 50; 34%) in addition to pulmonary vein isolation (6 of 69; 8.7%; P = 0.001). CONCLUSIONS: Prophylactic colchicine therapy initiated after the ablation procedure in patients with AF did not affect the incidence of post-ablation pericarditis and was associated with an increased incidence of gastrointestinal side effects.

Ripple mapping in ventricular tachycardia substrate mapping and ablation of nonischemic ventricular tachycardia.

INTRODUCTION: Substrate-based ablation for ventricular tachycardia (VT) using Ripple map (RM) is an effective treatment strategy for patients with ischemic cardiomyopathy but has yet to be evaluated in patients with nonischemic cardiomyopathy (NICMO). The aim of this study is to determine the feasibility and effectiveness of an RM-based ablation for NICMO patients. METHODS AND RESULTS: This was a single-center, retrospective study including all NICMO patients undergoing VT ablation at St Vincent Hospital between January 1, 2018 and January 12, 2019. Retrospective RM analysis was performed on those that had a substrate-based ablation to identify the location and number of Ripple channels as well as their proximity to ablation lesions. Thirty-three patients met the inclusion criteria and had a median age of 65 (58, 73.5) with 15.2% of the population being female, and were followed for a median duration of 451 (217.5, 586.5) days. Of these patients, 23 (69.7%) had a substrate-based ablation with a median procedural duration of 196.4 (186.8, 339) min, 1946 (517, 2750) points collected per map, and 277 (141, 554) points were within the scar. Two (8.6%) procedural complications occurred, and 7 (30.4%) patients had VT recurrence during follow-up. RM analysis revealed an average of two Ripple channels and the patients without VT recurrence had ablation performed closer to the Ripple channels: 0 (0, 4.7) versus 14.3 (0, 23.5) cm; p = .02. CONCLUSION: An RM-based substrate ablation can be performed in NICMO patients and ablation within Ripple channels is a predictor of VT freedom.

Rapid detection of isthmus block and rhythm change using local electrogram changes during complex atrial flutter ablation.

AIMS: Multiple re-entry circuits may operate simultaneously in the atria in the form of dual loop re-entry using a common isthmus, or multiple re-entrant loops without a common isthmus. When two or more re-entrant circuits coexist, ablation of an individual isthmus may lead to a seamless transition (without significant changes in surface electrocardiogram, coronary sinus activation or tachycardia cycle length) to a second rhythm, and the isthmus block can go unnoticed. METHODS AND RESULTS: We hypothesize and subsequently illustrate in three patient cases, methods to rapidly identify a transition in the rhythm and isthmus block using local electrogram changes at the ablation site. CONCLUSION: Local activation sequence changes, electrogram timing, and the behaviour of pre-existing double potentials can reveal isthmus block promptly when rhythm transitions occur during ablation of multiloop re-entry tachycardias.

Disparities in Practice Patterns by Sex, Race, and Ethnicity in Patients Referred for Advanced Heart Failure Therapies.

Advanced heart failure (HF) therapies improve survival in patients with stage D HF. We sought to evaluate differences by race/ethnicity and sex in advanced HF therapy referrals and decision-making across a multicenter survey. We performed a retrospective analysis of patients referred for evaluation for advanced HF therapies at 9 centers (n = 515) across the United States. The median age was 58 years, and 73% were male. White patients comprised 55.7% of referrals, whereas non-White patients comprised 44.3%. Non-ischemic etiology was more common in non-White patients (66.6% vs 47.4% p = 0.0005), and ischemic etiology was more common in men (37.8% vs 20.4% p = 0.0005). The primary reason for referral differed by race/ethnicity but not sex, with ventricular arrhythmias (7.6% vs 3%, p = 0.024) and pulmonary hypertension (3.4% vs 0.4% p = 0.018) being more common in White patients, whereas worsening HF was less common (25.4% vs 35.9%; p = 0.009). White patients were offered left ventricular assist devices (LVADs) (60.3% vs 54.7 p = 0.039) and heart transplants (51.8% vs 33.1% p = 0.0007) more often than non-White patients. The preference not to pursue LVAD therapy was more common in non-White patients (17.6% vs 9.6%; p = 0.049). Men were more often declined for a heart transplant because of psychosocial contraindications (34% vs 15%, p = 0.005). In conclusion, in this multicenter analysis of referrals for advanced HF therapies, we observed significant differences by race, ethnicity, and sex in both referral characteristics and evaluation outcomes. Further investigation is warranted to better understand why rates of LVAD and transplantation may be lower in non-White patients who are referred for advanced therapies.

Diagnostic utility of early premature ventricular complexes in differentiating atrioventricular reentrant and atrioventricular nodal reentrant tachycardias.

BACKGROUND: His-refractory premature ventricular complexes perturbing a supraventricular tachycardia (SVT) establish the presence of an accessory pathway (AP). Earlier premature ventricular complexes (ErPVCs) may perturb SVTs but are considered nondiagnostic. OBJECTIVE: The purpose of this study was to test the hypothesis that an ErPVC will always show a difference >35 ms in its advancement of the next atrial activation during atrioventricular nodal reentrant tachycardia (AVNRT). During atrioventricular reentrant tachycardia (AVRT), a PVC delivered close to the circuit can result in greater advancement of atrial activation due to retrograde conduction via an AP. Thus, an AP response, defined as ErPVC (H1S2) advancing the subsequent atrial activation (A1-A2) more than this minimum difference (A1A2 ≤ H1S2+35 ms), establishes the presence of an AP. METHODS: Sixty-five consecutive patients with SVT were retrospectively evaluated. ErPVCs were defined when the ventricular pacing stimulus was >35 ms ahead of the His during tachycardia. RESULTS: Among the 65 cases, 43 were AVNRT and 22 AVRT. Fourteen AVRT cases had an AP response with a mean H1S2+35 ms of 336 ± 58 ms and A1A2 of 309 ± 51ms. No AVNRT cases had an AP response. The specificity of an AP response to ErPVC in predicting AVRT was 100%. CONCLUSION: An AP response to PVCs (A1A2 ≤ H1S2+35 ms) is 100% specific for the presence of an AP.

Persistent 2-for-1 Atrioventricular Node Anterograde Conduction During a Supraventricular Tachycardia.

We present a case of persistent dual AV node conduction during AV node reentry tachycardia as a new clinical manifestation of 2-for-1 AV node conduction. The interpretation of the complex physiology ponders the possibility of an accessory pathway mediated atrioventricular reentry existing with more ventricular than atrial events.

Post-ablation P wave characteristics correlate with recurrent atrial fibrillation in the ABCD-AF cohort.

PURPOSE: Atrial fibrillation (AF) ablation is a common procedure to reduce cardiovascular morbidity but is limited by recurrence. The objective of this study was to determine if post-ablation acute surface P wave morphology and other electrocardiographic parameters correlate with AF recurrence. METHODS: The Avoiding Bladder Catheters During AF ablation (ABCD-AF) trial was a randomized, prospective trial in 160 subjects undergoing AF ablation. The present study examined correlation between AF recurrence in follow-up and acute post-ablation electrocardiographic P wave parameters. RESULTS: Median follow-up was 255 (188, 306) days. The ABCD-AF cohort had a mean age of 62.7 ± 12.8 with 32.1% being females. Rate of recurrent AF was 35.8%, with a median time to AF of 135 (109, 182) days. There was no baseline demographic associated with AF recurrence. There was more AF recurrence in those with longer follow-up (p = 0.001). Lead 2 PR interval, lead 2 P wave duration/PR (Pdur/PR), lead V1 PR interval, and lead V1 Pdur/PR were all significantly associated with recurrent AF (p = 0.03, 0.02, 0.01, 0.01). Longer PR and shorter Pdur/PR predicted AF recurrence. In a multivariable model, lead V1 Pdur/PR provided the best predictor of AF recurrence, with an odds ratio of 0.018 (p = 0.016) per standard deviation change. CONCLUSIONS: Shorter P wave duration combined with longer AV node delay, as measured by proportion of the PR that the P wave occupies, was the best predictor of AF recurrence post-ablation.

Rate Control Versus Rhythm Control in Patients with Left Ventricular Assist Devices and Atrial Fibrillation.

BACKGROUND: Atrial fibrillation (AF) is a common comorbidity in patients with left ventricular assist devices (LVAD) with no defined guideline treatment strategy of rate versus rhythm control. The purpose of this study is to determine the effects of rate versus rhythm control for AF on the outcomes of patients with LVAD at our institution. METHODS: Consecutive patients who underwent LVAD implantation at St Vincent Hospital from January 1, 2015 to December 31, 2017 were retrospectively evaluated. Patients with AF were identified and divided into rate control or rhythm control groups. The primary outcome evaluated was a composite of death, heart failure admission, gastrointestinal bleed, ventricular tachycardia, cerebrovascular accident, hemolysis, and pump thrombosis. Secondary outcomes included the individual variables from the primary outcome. RESULTS: Out of 201 patients that underwent LVAD implantation, 81 had AF after implantation and were included with a median follow-up period of 384 days. The rate control group (n = 31; 38%) and the rhythm control group (n = 51; 62%) had no difference in composite outcomes (61% vs 59%, p = 0.83). When taken individually there was no difference in outcomes between the two groups. Thirteen patients underwent electrical cardioversion and successful conversion to normal sinus rhythm occurred in 71% of cases with a 60% recurrence rate. CONCLUSIONS: There was no difference in primary outcome between rate and rhythm control groups. These data suggest that maintenance of sinus rhythm may not be necessary in all patients with LVAD.

The Tennessee Medicaid medication therapy management program: early stage contextual factors and implementation outcomes.

BACKGROUND: First investigated in the 1990s, medication therapy management (MTM) is an evidence-based practice offered by pharmacists to ensure a patient's medication regimen is individualized to include the safest and most effective medications. MTM has been shown to a) improve quality of patient care, b) reduces health care costs, and c) lead to fewer medication-related adverse effects. However, there has been limited testing of evidence-based, a-priori implementation strategies that support MTM implementation on a large scale. METHODS: The study has two objectives assessed at the organizational and individual level: 1) to determine the adoption, feasibility, acceptability and appropriateness of a multi-faceted implementation strategy to support the MTM pilot program in Tennessee; and 2) to report on the contextual factors associated with program implementation based on the Consolidated Framework for Implementation Research (CFIR). The overall design of the study was a hybrid type 2 effectiveness-implementation study reporting outcomes of Tennessee state Medicaid's (TennCare) MTM Pilot program. This paper presents early stage implementation outcomes (e.g., adoption, feasibility, acceptability, appropriateness) and explores implementation barriers and facilitators using the CFIR. The study was assessed at the (a) organizational and (b) individual level. A mixed-methods approach was used including surveys, claims data, and semi-structured interviews. Interview data underwent initial, rapid qualitative analysis to provide real time feedback to TennCare leadership on project barriers and facilitators. RESULTS: The total reach of the program from July 2018 through June 2020 was 2033 MTM sessions provided by 17 Medicaid credentialed pharmacists. Preliminary findings suggest participants agreed that MTM was acceptable (µ = 16.22, SD = 0.28), appropriate (µ = 15.33, SD = 0.03), and feasible (µ = 14.72, SD = 0.46). Each of the scales had an excellent level of internal (> 0.70) consistency (feasibility, α = 0.91; acceptability, α = 0.96; appropriateness, α = 0.98;). Eight program participants were interviewed and were mapped to the following CFIR constructs: Process, Characteristics of Individuals, Intervention Characteristics, and Inner Setting. Rapid data analysis of the contextual inquiry allowed TennCare to alter initial implementation strategies during project rollout. CONCLUSION: The early stage implementation of a multi-faceted implementation strategy to support delivery of Tennessee Medicaid's MTM program was found to be well accepted and appropriate across multiple stakeholders including providers, administrators, and pharmacists. However, as the early stage of implementation progressed, barriers related to relative priority, characteristics of the intervention (e.g., complexity), and workflow impeded adoption. Programmatic changes to the MTM Pilot based on early stage contextual analysis and implementation outcomes had a positive impact on adoption.

Stroke, Timing of Atrial Fibrillation Diagnosis, and Risk of Death.

OBJECTIVE: 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. We also evaluated initiation of anticoagulants and antiplatelets across the study duration. Cox proportional hazards models evaluated associations between stroke subtypes and death. RESULTS: We identified 1,489 individuals who developed an incident ischemic stroke event: 985 did not develop AF at any point during the study period, 215 had KAF before stroke, 160 had AF detected ≤6 months after stroke, and 129 had AF detected >6 months after stroke. After a median follow-up of 4.9 years (interquartile range 1.9-6.8), 686 deaths occurred. The annualized mortality rate was 8.8% in the stroke, no AF group; 12.2% in the KAF group; 15.8% in the AFDAS ≤6 months group; and 12.7% in the AFDAS >6 months group. Patients in the AFDAS ≤6 months group had the highest independent risk of all-cause mortality even after multivariable adjustment for demographics, clinical risk factors, and the use of antithrombotic therapies (hazard ratio 1.62 [1.22-2.14]). Compared to the stroke, no AF group, those with KAF had a higher mortality risk that was rendered nonsignificant after adjustment. CONCLUSIONS: The AFDAS group had the highest risk of death, which was not explained by comorbidities or use of antithrombotic therapies.

Incidence of Cardiac Implantable Electronic Device Complications in Patients With Left Ventricular Assist Devices.

OBJECTIVES: The objective of this study was to describe the risk of cardiac implantable electronic devices (CIEDs) complications in patients with left ventricular assist devices (LVADs). BACKGROUND: Patients with LVADs are predisposed to ventricular arrhythmias and frequently have CIEDs before receiving their LVAD. However, the role of CIED procedures such as generator changes (GC) are unclear in this population, given the potential complications of bleeding and infection. METHODS: This was a retrospective, multicenter study from January 1, 2012, to September 30, 2018. All patients with LVADs were screened and those who had a CIED GC, implantation, or revision were included in the study and followed until December 31, 2018. RESULTS: A total of 179 patients across 6 centers had a CIED procedure after LVAD implantation. The mean age was 59.5 ± 13.4, with the cohort comprising mostly men (78%), destination LVAD therapy (53.8%), and GC (66%). The 30-day primary composite endpoint of hematoma or device infection occurred in 34 (19%) patients. The secondary endpoints of rehospitalization within 30 days and appropriate device therapy during follow-up occurred in 40 (22%) and 42 (24%) patients respectively. Of the 126 patients without previous device therapy, 14.3% received appropriate therapy during follow-up. CONCLUSIONS: In this large, multicenter cohort, we report the incidence of complications for CIED procedures in the LVAD population; specifically, LVAD patients are at increased risk of pocket hematomas, without downstream risk of infection, and do experience a high rate of appropriate device therapies.

Left atrial hypertension and the risk of early incident heart failure after atrial fibrillation ablation.

INTRODUCTION: Elevated left atrial pressure (LAP) during catheter ablation of atrial fibrillation (AF) is associated with an increased risk of AF recurrence, but it is unknown if this correlates with heart failure (HF). The objective of the study was to determine if elevated LAP after AF ablation correlates with HF events. METHODS: Prospective, single-center, cohort study measuring LAP and right atrial pressure (RAP) during AF ablation in 100 patients. The primary endpoint was clinical HF within 30 days of ablation. The secondary outcome was AF-free HF. RESULTS: One hundred patients (63% male, mean age 64.5) were enrolled and 20% had clinical HF within 30 days. Bivariate correlates included mitral valve (MV) disease, persistent AF, class III antiarrhythmics, LAP, and recurrent AF. Multivariate analysis revealed class III antiarrhythmics were protective (odds ratio [OR]: 0.24 [0.1-0.5], p = .04), while MV disease (OR: 8.7 [3.3-23], p = .03) and loop diuretics (OR: 4.8 [2.6-9.1], p = .01) were hazardous. AF-free HF occurred in 9% of patients and correlated with higher LAP and RAP, and chronic kidney disease. CONCLUSION: Patients with HF after AF ablation had higher LAP. MV disease, diuretic use, and class III antiarrhythmics also correlated to HF. These present opportunities to target future interventions to reduce a common complication of AF ablation.

Mechanism and interpretation of two-for-one response to premature atrial complexes during atrioventricular node re-entry tachycardia.

AIMS: The response to premature atrial complexes (PACs) during tachycardia has been shown to differentiate atrioventricular nodal re-entrant tachycardia (AVNRT) from focal junctional tachycardia (JT). His refractory PAC (HrPACs) perturbing the next His (resetting with fusion) is diagnostic of AVNRT and such a late PAC fusing with the native beat cannot reset the focal source of JT. Early PAC advancing the immediate His with continuation of tachycardia suggests JT but can also occur in AVNRT due to simultaneous conduction through the AV nodal fast and slow pathways [two-for-one response (TFOR)]. The objective of this study was to evaluate the incidence and mechanism of TFOR after early premature atrial complexes (ePACs) during AVNRT and to differentiate it from the known response to ePACs during JT. METHODS AND RESULTS: Typical AVNRT cases were diagnosed using standard criteria. We evaluated the responses to scanning PACs delivered during tachycardia in 100 patients undergoing AV node slow pathway modification for AVNRT. The responses to HrPACs and ePACs delivered from coronary sinus os or high right atrium were retrospectively reviewed. In 10 patients, ePACs advanced the immediate His with continuation of tachycardia. In all 10 cases, HrPACs advanced the next His, confirming AVNRT as the mechanism, and indicating a TFOR. CONCLUSION: A TFOR can occur in a small number of patients during AVNRT and is therefore not diagnostic of JT. However, HrPACs always perturbed the next His in these cases, confirming the diagnosis of AVNRT and allowing for differentiation from JT.

Efficacy of Single Transverse Neck Incision for Modified Radical Neck Dissection.

BACKGROUND: To assess the viability of the single transverse neck incision (STNI) for modified radical neck dissection and to analyze the yield of lymph nodes using this approach. MATERIALS AND METHODS: We conducted a prospective observational study in the Department of Head and Neck Surgical Oncology at our Tertiary Cancer Care Centre from November 2013 to May 2017. RESULTS: A total of 257 patients underwent surgical treatment for malignant tumors of the head and neck which included 265 modified radical neck dissections (eight bilateral and 249 unilateral). Average of total dissected nodal yield was 37.07. Average yield of positive neck nodes was 2.78. CONCLUSION: Single transverse neck incision is an acceptable technique for modified radical neck dissection as it provides adequate surgical exposure for achieving optimal nodal clearance with little technical difficulty.