Cryoballoon pulmonary vein isolation versus radiofrequency ablation of the pulmonary veins and left atrial posterior wall: Patient-reported outcomes.

BACKGROUND: Data are lacking on patient-reported outcomes (PRO) following cryoballoon ablation (CBA) versus radiofrequency ablation (RFA). We sought to evaluate QoL and clinical outcomes of cryoballoon pulmonary vein isolation only (CRYO-PVI-ONLY) versus RFA with PVI and posterior wall isolation (RF-PVI+PWI) in a large prospective PRO registry. METHODS: Patients who underwent AF ablation (2013-2016) at our institution were enrolled in an automated, prospectively maintained PRO registry. CRYO-PVI-ONLY patients were matched (1:1) with RF-PVI+PWI patients based on age, gender, and type of AF (paroxysmal vs. persistent). QoL and clinical outcomes were assessed using PRO surveys at baseline and at 1-year. The atrial fibrillation symptom severity scale (AFSSS) was the measure for QoL. Additionally, we assessed patient-reported clinical improvement, arrhythmia recurrence, and AF burden (as indicated by AF frequency and duration scores). RESULTS: A total of 296 patients were included (148 in each group, 72% paroxysmal). By PRO, a significant improvement in QoL was observed in the overall study population and was comparable between CRYO-PVI-ONLY and RF-PVI+PWI (baseline median AFSSS of 11.5 and 11; reduced to 2 and 4 at 1 year, respectively; p = 0.44). Similarly, the proportion of patients who reported improvement in their overall QoL and AF related symptoms was high and similar between the study groups [92% (CRYO-PVI-ONLY) vs. 92.8% (RF-PVI+PWI); p = 0.88]. Arrhythmia recurrence was significantly more common in the CRYO-PVI-ONLY group (39.7%) compared to RF-PVI+PWI (27.7 %); p = 0.03. Comparable results were observed in paroxysmal and persistent AF. CONCLUSION: CRYO-PVI-ONLY and RF-PVI+PWI resulted in comparable improvements in patient reported outcomes including QoL and AF burden; with RF-PVI+PWI being more effective at reducing recurrences.

Electrical Dyssynchrony in Cardiac Amyloidosis: Prevalence, Predictors, Clinical Correlates, and Outcomes.

BACKGROUND: Conduction-system involvement in cardiac amyloidosis (CA) is common. The prevalence, clinical correlates and impact on outcome related to ventricular electrical dyssynchrony in CA remain insufficiently elucidated. METHODS: Data from a prospectively maintained registry of patients with CA diagnosed in the Cleveland Clinic's amyloidosis clinic was used to determine the frequency of electrical dyssynchrony (defined as a QRS > 130 msec). The relation with the clinical profile and clinical outcome was assessed. To determine the impact of hypertrophy on QRS prolongation, a QRS-matched cohort without CA was used for comparison of cardiac magnetic resonance imaging. RESULTS: A total of 1140 patients with CA (39% AL, 61% TTR) were evaluated, of whom 230 (20%) had electrical dyssynchrony. The type of conduction block was predominantly a right bundle branch block (BBB, 48%) followed by left BBB (35%) and intraventricular conduction delay (17%). Presence of transthyretin amyloidosis (ATTR-CA), older age, male gender, white race, and coronary artery disease were independently (P< 0.05 for all) associated with electrical dyssynchrony, and patients were more commonly prescribed a mineralocorticoid receptor antagonist. In ATTR-CA, specifically, every increase in ATTR-CA disease stage was associated with a 1.55-fold (1.23--1.95; P< 0.001) increased odds for electrical dyssynchrony. In a subset of patients with CA who underwent cardiac magnetic resonance imaging (n = 41), left ventricular mass index was unrelated to the QRS duration (r = 0.187; P = 0.283) in CA, in contrast to a non-CA QRS-matched cohort (r = 0.397; P< 0.001). Patients with electrical dyssynchrony were more symptomatic at initial presentation, as illustrated by a higher New York Heart Association class (P= 0.041). During a median follow-up of 462 days (IQR:138--996 days), a higher proportion of patients with electrical dyssynchrony died from all-cause death (P= 0.037) or developed a permanent pacing indication (3% vs 10.4%; P< 0.001) during follow-up. CONCLUSION: Electrical dyssynchrony is common in CA, especially in ATTR-CA, and is associated with worse functional status and clinical outcome. Given the high rate of permanent pacing indications at follow-up, additional studies are necessary to determine the best monitoring and pacing strategies in CA.

Cardiac resynchronisation therapy in anthracycline-induced cardiomyopathy.

INTRODUCTION: Chemotherapy-induced cardiomyopathy has been increasingly recognised as patients are living longer with more effective treatments for their malignancies. Anthracyclines are known to cause left ventricular (LV) dysfunction. While heart failure medications are frequently used, some patients may need consideration for device-based therapies such as cardiac resynchronisation therapy (CRT). However, the role of CRT in anthracycline-induced cardiomyopathy (AIC) is not well understood. METHODS: We performed a retrospective review of all patients undergoing CRT implantation at our centre from 2003 to 2019 with a diagnosis of AIC. The LV remodelling and survival outcomes of this population were obtained and then compared with consecutive patients with other aetiologies of non-ischaemic cardiomyopathy (NICM). RESULTS: A total of 34 patients underwent CRT implantation with a diagnosis of AIC with a mean age of 60.5±12.7 years, left ventricular ejection fraction (LVEF) of 21.7%±7.4%, and 11.3±7.5 years and 10.2±7.4 years from cancer diagnosis and last anthracycline exposure, respectively. At 9.6±8.1 months after CRT implantation, there was an increase of LVEF from 21.8%±7.6% to 30.4%±13.0% (p<0.001). Patients whose LVEF increased by at least 10% post-CRT implant (42.5% of cohort) survived significantly longer than patients who failed to improve their LVEF by that amount (p=0.01). A propensity matched analysis between patients with AIC and 369 consecutive patients with other aetiologies of NICM who underwent CRT implantation during the same period revealed no significant differences in improvement in LVEF or long-term survival. CONCLUSIONS: Patients with AIC undergo LV remodelling with CRT at rates similar to other aetiologies of NICM. Furthermore, AIC post-CRT responders have a favourable long-term mortality compared with non-responders.

Comparative Analysis of Procedural Outcomes and Complications Between De Novo and Upgraded Cardiac Resynchronization Therapy.

OBJECTIVES: This study compared rates of procedural success and complications between de novo cardiac resynchronization therapy (CRT) implantation versus upgrade, including characterization of technical challenges. BACKGROUND: CRT upgrade is common, but data are limited on the incidence of procedural success and complications as compared to de novo implantation. METHODS: All patients who underwent a transvenous CRT procedure at a single institution between 2013 and 2018 were reviewed for procedure outcome, 90-day complications, reasons for unsuccessful left ventricular lead delivery, and the presence of venous occlusive disease (VOD) that required a modified implantation technique. RESULTS: Among 1,496 patients, 947 (63%) underwent de novo implantation and 549 (37%) underwent device upgrade. Patients who received a device upgrade were older (70 ± 12 years vs. 68 ± 13 years; p < 0.01), with a male predominance (75% vs. 66%; p < 0.01) and greater prevalence of comorbidities. There was no difference in the rate of procedural success between de novo and upgrade CRT procedures (97% vs. 96%; p = 0.28) or 90-day complications (5.1% vs. 4.6%; p = 0.70). VOD was present in 23% of patients who received a device upgrade and was more common among patients with a dual-chamber versus a single-chamber device (26% vs. 9%; p < 0.001). Patients with and without VOD had a similar composite outcome of procedural failure or complication (8.0% vs. 7.8%; p = 1.0). CONCLUSIONS: Rates of procedural success and complications were no different between de novo CRT implantations and upgrades. VOD frequently increased procedural complexity in upgrades, but alternative management strategies resulted in similar outcomes. Routine venography before CRT upgrade may aid in procedural planning and execution of these strategies.

Ablation of Atrial Fibrillation Without Left Atrial Appendage Imaging in Patients Treated With Direct Oral Anticoagulants.

BACKGROUND: Many centers continue to routinely perform transesophageal echocardiograms before atrial fibrillation (AF) ablation procedures in patients treated with direct oral anticoagulants (DOACs). One study suggested that the procedures could be done without transesophageal echocardiogram but used intracardiac echocardiography imaging of the appendage from the right ventricular outflow. This study aimed to assess the safety of ablation for AF without transesophageal echocardiogram screening or intracardiac echocardiography imaging of the appendage in DOAC compliant patients. METHODS: All patients undergoing AF ablation at the Cleveland Clinic (2011-2018) were enrolled in a prospectively maintained data registry. All consecutive patients presenting with AF or atrial flutter on DOAC were included. Periprocedural thromboembolic complications were assessed. RESULTS: A total of 900 patients were included. Their median CHA2DS2-VASc score was 2 (interquartile range 1-3). All were on DOACs (333 rivaroxaban, 285 dabigatran, 281 apixaban, and 1 edoxaban). Thromboembolic complications occurred in 4 patients (0.3%): 2 ischemic strokes, 1 transient ischemic attack without residual deficit, and 1 splenic infarct; all with no further complications. Bleeding complications occurred in 5 patients (0.4%): 2 pericardial effusions (1 intraoperative, 1 after 30 days, both drained), 3 groin hematomas (1 of them due to needing heparin for venous thrombosis, none required interventions). No patients required emergent surgeries. CONCLUSIONS: In DOAC compliant patients who present for ablation in AF/atrial flutter, the procedures could be performed without transesophageal echocardiogram screening or intracardiac echocardiography imaging of the appendage; with low risk of complications.

The Utility of Rapid Atrial Pacing Immediately Post-TAVR to Predict the Need for Pacemaker Implantation.

OBJECTIVES: The aim of this study was to determine the utility of rapid atrial pacing immediately after transcatheter aortic valve replacement (TAVR) to predict the need for permanent pacemaker implantation (PPI). BACKGROUND: Risk stratification for patients without high-grade atrioventricular block (AVB) after TAVR is imprecise and based on anatomic considerations, electrocardiographic characteristics, and clinical suspicion. A more reliable assessment is necessary to minimize inpatient rhythm monitoring and/or reduce unnecessary PPI. METHODS: Consecutive patients undergoing TAVR at 2 centers were included. After valve implantation in patients without pacemakers who did not have complete heart block or atrial fibrillation, the temporary pacemaker was withdrawn from the right ventricle and placed in the right atrium. Rapid atrial pacing was performed from 70 to 120 beats/min, and patients were assessed for the development of Wenckebach AVB. Patients were then followed for clinical outcomes, including PPI. RESULTS: A total of 284 patients were included. Of these, 130 (45.8%) developed Wenckebach AVB. There was a higher rate of PPI within 30 days of TAVR among the patients who developed Wenckebach AVB (13.1% vs. 1.3%; p < 0.001), with a negative predictive value for PPI in the group without Wenckebach AVB of 98.7%. A greater percentage of patients receiving self-expanding valves required PPI than those receiving a balloon-expandable valves (15.9% vs. 3.7%; p = 0.001), though these rates were still relatively low among patients who did not develop Wenckebach AVB (2.9% and 0.8%). CONCLUSIONS: Atrial pacing post-TAVR is easily performed and can help identify patients who may benefit from extended rhythm monitoring. Patients who did not develop pacing-induced Wenckebach AVB demonstrated an extremely low likelihood of PPI.

Transvenous Lead Extraction in Patients With Arrhythmogenic Right Ventricular Cardiomyopathy.

OBJECTIVES: This study aimed to evaluate the effectiveness and safety of transvenous lead extraction (TLE) in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC). BACKGROUND: ARVC is an increasingly diagnosed cardiomyopathy that often requires device implantation to prevent sudden death. Little is known about TLE in this setting, which has potential challenges and risks, primarily due to right ventricular (RV) wall thinning and fragility. METHODS: All consecutive patients with ARVC who underwent TLE at our institution between 1996 and 2016 were included. When extraction tools were used, sheaths were advanced to the RV with countertraction at the lead tip. Success and complications were defined in concordance with Heart Rhythm Society guidelines. RESULTS: Twenty-two TLE procedures in patients with ARVC involved extraction of 27 leads (22 defibrillators and 5 pacemakers). TLEs were performed due to evidence of lead malfunction (n = 17; 77%) or device infection (n = 5; 23%). Twenty-four leads (89%) were RV, and 3 leads (11%) were right atrial. The median age of the oldest extracted lead was 1,691 days (interquartile range [IQR]: 1,168 to 2,726 days). Specialized extraction tools were required in 20 procedures (91%). None required the use of a snare or a femoral workstation. The median procedural and fluoroscopic times were 152 min (IQR: 129 to 185 min) and 11 min (IQR: 6 to 18 min), respectively. Complete procedural success with removal of all leads was achieved in all cases. There were no major complications. CONCLUSIONS: In a high-volume center, TLE in patients with ARVC was associated with a high success rate and a low rate of complications when guideline-established techniques and tools were used.

Recurrent Atrial Fibrillation After Initial Long-Term Ablation Success: Electrophysiological Findings and Outcomes of Repeat Ablation Procedures.

BACKGROUND: Atrial fibrillation recurrence after initial long-term success of catheter ablation has been described, yet not well studied. We assessed the electrophysiological findings and outcomes of repeat ablation procedures in this setting. METHODS AND RESULTS: Between 2000 and 2015, 10 378 patients underwent atrial fibrillation ablation and were enrolled in a prospectively maintained data registry. From this registry, we included all 137 consecutive patients who had initial long-term success, defined as freedom from recurrent arrhythmia for >36 months off antiarrhythmics, then underwent repeat ablation for recurrent atrial fibrillation. The median arrhythmia-free period that defined long-term success was 52 months (41-68 months). In redo ablations, reconnection along at least one of the pulmonary veins (PVs) was found in 111 (81%) patients. Reconnection along a left superior, left inferior, right superior, and right inferior PV was found in 64%, 62%, 50%, and 54% of patients, respectively, and were reisolated. Additional non-PV ablations were performed in 127 (92.7%) patients: posterior wall (46%), septal to right PVs (49%), superior vena cava (35%), roof lines (52%), and cavotricuspid isthmus (33%). After a median follow-up of 17 months (5-36.9 months), 103 patients (75%) were arrhythmia free (79 off antiarrhythmics, 24 on antiarrhythmics). CONCLUSIONS: PV reconnection is the most common electrophysiological finding in patients with atrial fibrillation recurrence after long-term success, but with lower rates than what had been reported for early recurrences. In our experience, repeat ablations in this setting involve complex ablation approaches to reisolate the PVs and modify the atrial substrate and are associated with good success rates.

Incidence and predictors of late atrioventricular conduction recovery among patients requiring permanent pacemaker for complete heart block after cardiac surgery.

BACKGROUND: New-onset complete heart block (CHB) commonly complicates cardiac surgery, for which some patients require a permanent pacemaker (PPM). Little is known regarding late atrioventricular (AV) conduction recovery. OBJECTIVE: The purpose of this study was to characterize the incidence and predictors of late AV conduction recovery among patients requiring PPM after cardiac surgery. METHODS: Consecutive patients receiving PPM for CHB after cardiac surgery at a high-volume U.S. center from 2000 to 2014 were evaluated. The primary outcome was late AV conduction recovery, defined as a reduction in ventricular pacing requirement to <10% beyond 1 month postimplant. Regression analysis was performed to evaluate predictors of AV recovery. RESULTS: Among 301 patients evaluated over 4 ± 4 years of follow-up, the incidence of late AV conduction recovery was 12% (n = 37), for whom the median ventricular pacing requirement decreased from 96% at implant to <1% at 6 months and persisted throughout study follow-up. AV recovery was less common when preoperative conduction abnormalities were present, including no recovery among patients with preoperative PR >200 ms and QRS >120 ms (n = 42). Multivariable analysis identified only female sex and transient AV conduction postoperatively as independent predictors of recovery (odds ratio 3.5; P <.01 for each). Neither cardiac surgery subtype nor PPM implant timing postoperatively was significantly associated with recovery. CONCLUSION: Late AV conduction recovery is not uncommon after cardiac surgery, occurring in 1 of 8 patients within 6 months postoperatively. Preoperative AV conduction abnormalities were associated with decreased recovery, whereas female sex and transient postoperative AV conduction were associated with increased recovery.

Randomized Study of Persistent Atrial Fibrillation Ablation: Ablate in Sinus Rhythm Versus Ablate Complex-Fractionated Atrial Electrograms in Atrial Fibrillation.

BACKGROUND: Achieving long-term successful outcomes with ablation of persistent atrial fibrillation (AF) remains a clinical and procedural challenge. We aimed to assess 2 ablation strategies for persistent AF: pulmonary vein antral isolation (PVAI) in sinus rhythm after direct current cardioversion versus PVAI and ablation targeting complex-fractionated atrial electrograms while in AF. METHODS AND RESULTS: Between June 2009 and July 2013, patients with continuous persistent AF for ≥3 months were prospectively randomized to either direct current cardioversion before PVAI and posterior wall/septum ablation while in sinus rhythm (group 1), versus same ablation in group 1 in addition to complex-fractionated atrial electrogram ablation while in AF (group 2). The procedural profiles and clinical outcomes of the 2 strategies were compared. Ninety patients were randomized to group 1 (n=46) or group 2 (n=44). There were no differences in baseline characteristics between groups. Over 365 days of follow-up after the index procedure, 16 patients (35%) in group 1 and 13 patients (30%) in group 2 remained arrhythmia-free off antiarrhythmic medications. Over long-term follow-up (median, 867 days), arrhythmia-free survival off antiarrhythmic medications was more likely in group 1 than in group 2 in Kaplan-Meier analysis (Log Rank P=0.04). Group 1 ablation was associated with significantly shorter procedural duration and fluoroscopy time (231±72 versus 273±76 min; P=0.008 and 54 [Q1-Q3: 46-67] versus 66 (Q1-Q3: 53-83] min; P=0.018, respectively). CONCLUSIONS: In patients with persistent AF, PVAI in sinus rhythm after direct current cardioversion is associated with higher success and shorter procedural and fluoroscopy times compared with PVAI in AF with additional complex-fractionated atrial electrogram ablation. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02429648.

Outcomes of nonpharmacologic treatment of atrial fibrillation in patients with hypertrophic cardiomyopathy.

BACKGROUND: Limited data exist regarding the outcome of atrial fibrillation (AF) surgery and catheter ablation in patients with hypertrophic cardiomyopathy (HCM). OBJECTIVE: The purpose of this study was to evaluate the safety and efficacy of nonpharmacologic treatment of AF in HCM. METHODS: One hundred forty-seven patients (46 female, age 55 ± 11 years, ejection fraction [EF] 58% ± 8%) with symptomatic paroxysmal (58%), persistent (31%), and long-standing persistent AF (11%) refractory to antiarrhythmic drugs who presented for their first catheter ablation (n = 79) or AF surgery (n = 68) were included. RESULTS: After follow-up of 35 months (interquartile range 13, 60), 29% of patients who underwent catheter ablation and 51% of those who had undergone AF surgery had no documented recurrent atrial arrhythmia after a single procedure. Repeat ablation was performed in 55% of patients with recurrent arrhythmia in the catheter group and 24% in the surgery group, increasing the success rate to 39% and 53%, respectively, after 1 or more procedures. Predictors of success after the first procedure in a multivariable setting included higher baseline EF and male gender. Persistent or long-standing AF and log of AF duration were associated with lower success. Major complications occurred in 6% of the catheter ablation group and 18% of the AF surgery group. During follow-up, 16 patients died (9 in catheter group, 7 in surgery group) and 1 underwent heart replacement. Lower baseline EF and older age were independently associated with death. CONCLUSION: Catheter ablation and AF surgery are associated with symptomatic improvement in HCM patients. However, long-term success is lower and complications are higher than previously reported.

Exercise-induced syncope in a sedentary woman.

Vasovagal (neurocardiogenic) syncope, a subtype of reflex syncope, has many well-known triggers. However, we found no previous report of vasovagal exercise-induced syncope in a sedentary person. We present the case of a 35-year-old sedentary woman who experienced vasovagal syncope as she underwent an exercise stress test. Results of evaluations, including resting and stress electrocardiography and echocardiography, were normal. Her presentation is highly unusual: syncope has typically not been associated with exercise except in young athletes, people with structural heart abnormalities, or people with a prolonged QT syndrome. To our knowledge, this is the first report of vasovagal syncope associated with exercise in a sedentary patient who had normal cardiac and electrophysiologic function. We suggest possible physiologic mechanisms and diagnostic strategies.

Usefulness of cardiac resynchronization therapy in patients with Adriamycin-induced cardiomyopathy.

Adriamycin is a chemotherapeutic agent that can cause severe cardiotoxicity, which potentially carries a poorer long-term prognosis than other forms of cardiomyopathy. Cardiac resynchronization therapy (CRT) has been shown to improve quality of life, exercise capacity, left ventricular ejection fraction, and survival in selected patients with heart failure. It is unclear if patients with Adriamycin-induced cardiomyopathy (AIC) respond to CRT. We reviewed clinical and echocardiographic data on 18 consecutive patients with AIC who underwent implantation of a CRT device at the Cleveland Clinic from February 2000 to April 2007. Changes in clinical and echocardiographic parameters were compared to 189 consecutive patients with other forms of nonischemic cardiomyopathy (NIC) using similar end points. Patients with AIC demonstrated significant improvements in ejection fraction, left ventricular end-diastolic and end-systolic diameters, mitral regurgitation, and New York Heart Association functional class with CRT. These changes were similar to patients in the NIC cohort. In conclusion, patients with AIC may derive a significant echocardiographic and symptomatic benefit from CRT, which is similar to that seen in other forms of NIC.