Targeting non-pulmonary vein triggers in persistent atrial fibrillation: results from a prospective, multicentre, observational registry.

AIMS: We evaluated the efficacy of an ablation strategy empirically targeting pulmonary veins (PVs) and posterior wall (PW) and the prevalence and clinical impact of extrapulmonary trigger inducibility and ablation in a large cohort of patients with persistent atrial fibrillation (PerAF). METHODS AND RESULTS: A total of 1803 PerAF patients were prospectively enrolled. All patients underwent pulmonary vein antrum isolation (PVAI) extended to the entire PW. A standardized protocol was performed to confirm persistent PVAI and elicit any triggers originating from non-PV sites. All non-PV triggers initiating sustained atrial tachyarrhythmias were ablated. Ablation of non-PV sites triggering non-sustained runs (<30 s) of atrial tachyarrhythmias or promoting frequent premature atrial complexes (≥10/min) was left to operator's discretion. Overall, 1319 (73.2%) patients had documented triggers from non-PV areas. After 17.4 ± 8.5 months of follow-up, the cumulative freedom from atrial tachyarrhythmias among patients without inducible non-PV triggers (n = 484) was 70.2%. Patients with ablation of induced non-PV triggers had a significantly higher arrhythmia control than those whose triggers were not ablated (67.9% vs. 39.4%, respectively; P < 0.001). After adjusting for clinically relevant variables, patients in whom non-PV triggers were documented but not ablated had an increased risk of arrhythmia relapse (hazard ratio: 2.39; 95% confidence interval: 2.01-2.83; P < 0.001). CONCLUSION: Pulmonary vein antrum isolation extended to the entire PW might provide acceptable long-term arrhythmia-free survival in PerAF patients without inducible non-PV triggers. In our population of PerAF patients, non-PV triggers could be elicited in ∼70% of PerAF patients and their elimination significantly improved outcomes.

Outcomes of patients admitted with ventricular arrhythmias and sudden cardiac death in the United States.

BACKGROUND: Mortality caused by ventricular arrhythmias (VAs) remains a problem of epidemic proportions. Understanding current trends on admission of VA, patient characteristics, morbidity, mortality, and health care utilization could help us improve allocation of health care resources and risk prediction. OBJECTIVE: The purpose of this study was to investigate clinical outcomes of VA, including ventricular tachycardia (VT), implantable cardioverter-defibrillator (ICD) shocks, and sudden cardiac death (SCD); and to identify predictors of morbidity and mortality, patterns of utilization of ICD and VT ablation, and the impact of such metrics on overall health care utilization. METHODS: From 2010-2015, we identified 290,998 VA hospitalizations, which were stratified into group 1: normal heart; group 2: ischemic heart disease (IHD); group 3: nonischemic heart disease (non-IHD); group 4: ICD shocks; and group 5: SCD (cardiac arrest without ICD shock). RESULTS: The number of admissions for VA decreased during the study period (except for patients with SCD and ICD shock, which increased); in-hospital mortality in patients admitted with VA and SCD increased; utilization of VT ablation in patients with ICD shocks and IHD increased; ICD implantation decreased in non-IHD patients and IHD patients; and admission for SCD was the strongest predictor of in-hospital mortality, followed by patients with non-IHD, patients with ICD shocks, and all patients with a Charlson comorbidity index ≥2. CONCLUSION: We report a decrease in admissions for VA, decreased ICD utilization, a change in pattern of VT ablation utilization, and an increase of in-hospital mortality in SCD patients. Predictors of adverse outcomes identified in our study should be considered when developing risk models for patients undergoing risk assessment for SCD.

Surgical left atrial appendage occlusion during cardiac surgery: A systematic review and meta-analysis.

AIM: To evaluate the safety and efficacy of surgical left atrial appendage occlusion (s-LAAO) during concomitant cardiac surgery. METHODS: We performed a comprehensive literature search through May 31st 2018 for all eligible studies comparing s-LAAO vs no occlusion in patients undergoing cardiac surgery. Clinical outcomes during follow-up included: embolic events, stroke, all-cause mortality, atrial fibrillation (AF), reoperation for bleeding and postoperative complications. We further stratified the analysis based on propensity matched studies and AF predominance. RESULTS: Twelve studies (n = 40107) met the inclusion criteria. s-LAAO was associated with lower risk of embolic events (OR: 0.63, 95%CI: 0.53-0.76; P < 0.001) and stroke (OR: 0.68, 95%CI: 0.57-0.82; P < 0.0001). Stratified analysis demonstrated this association was more prominent in the AF predominant strata. There was no significant difference in the incidence risk of all-cause mortality, AF, and reoperation for bleeding and postoperative complications. CONCLUSION: Concomitant s-LAAO during cardiac surgery was associated with lower risk of follow-up thromboembolic events and stroke, especially in those with AF without significant increase in adverse events. Further randomized trials to evaluate long-term benefits of s-LAAO are warranted.

Painful left bundle branch block syndrome treated with his bundle pacing.

This is a case report of a patient with painful LBBB Syndrome that responded favorably to His Bundle Pacing. This syndrome is largely under recognized despite 50 reports in the literature over the last 60 years. Both diagnosis and treatment are not well defined and represent a major challenge in patients with this entity. Right ventricular pacing has been attempted with inconsistent efficacy outcomes. We report for the first-time complete resolution of chest pain with His bundle pacing. HBP provides a promising alternative pacing option that might provide symptom resolution to patients with a painful LBBB syndrome.

Cardiac Resynchronization Therapy in Inotrope-Dependent Heart Failure Patients: A Systematic Review and Meta-Analysis.

OBJECTIVES: The purpose of this study was to evaluate outcomes after cardiac resynchronization therapy (CRT) in inotrope-dependent patients with heart failure (HF) to ascertain the viability of CRT in these patients. BACKGROUND: During the last decade, significant numbers of trials have demonstrated the beneficial effect of CRT in the treatment of patients with HF and systolic dysfunction, prolonged QRS complex duration, and New York Heart Association functional class III or IV. However, it is currently undetermined whether CRT may benefit patients who require inotropic support. METHODS: The authors systematically searched Medline, Embase, Scopus, and the Cochrane Library through March 2017 for studies evaluating outcomes after CRT in inotrope-dependent patients with HF. The study analyzed 8 studies including 151 patients. Most of the patients were in New York Heart Association functional class IV (80.1%), and all had severe systolic HF, with a left ventricular ejection fraction <30% and a significant intraventricular conduction delay in their surface electrocardiogram (QRS complex duration >130 ms). RESULTS: The pooled analysis demonstrated that 93% of the reported patients (95% confidence interval: 86% to 100%) were weaned from inotropic support after CRT, and the overall 12-month survival rate was 69% (95% confidence interval: 56% to 83%). CONCLUSIONS: This study suggests that rescue CRT may be considered a viable therapeutic option in inotrope-dependent patients with HF. In these patients, rescue CRT may allow them to be weaned from inotropic therapy, improve their quality of life, and decrease the rate of mortality; furthermore, rescue CRT may serve as a possible bridge to cardiac transplantation or left ventricular assist device therapy.

Anticoagulation After Catheter Ablation of Atrial Fibrillation: Is it time to Discontinue in Select Patient Population?

BACKGROUND: Catheter ablation is an effective strategy for treatment of drug-refractory atrial fibrillation (AF). Continuation of oral anticoagulation (OAC) beyond 3 months after an apparently successful ablation of AF remains controversial. METHODS: A systematic electronic search of the scientific literature was performed in PubMed, EMBASE, SCOPUS and Google Scholar. Studies comparing continuation vs discontinuation of OACs after an apparent successful ablation of AF among patients with CHA2DS2VASC or CHADS2 score ≥2were included. Clinical outcomes included cerebrovascular events, systemic thromboembolism and major bleeding. Risk ratios (RR) and 95% confidence intervals for above outcomes were calculated. RESULTS: Nine observational studies were eligible and included 3,436patients of whom 1,815 continued OACs and1,621 discontinued OAC post -AF ablation. There was no significant difference in risk of cerebrovascular events (RR: 0.85, 95%CI: 0.42 to 1.70, p= 0.64)and systemic thromboembolism (RR: 1.21, 95%CI: 0.66 to 2.23, p= 0.54)between the two groups. Continuation of OACs was associated with an increased risk of major bleeding (RR: 6.50, 95% CI: 2.53 to 16.74, p= 0.0001). CONCLUSION: In conclusion, discontinuation of oral anticoagulation 3 months after a successful AF ablation appears to be safe in highly selected closely monitored patients. Further randomized trials are warranted to assess the safety of discontinuing OACs after AF ablation.

Role of Cardiac Imaging in Evaluating Risk for Sudden Cardiac Death.

Sudden cardiac death (SCD) is a major cause of death from cardiovascular disease. Our ability to predict patients at the highest risk of developing lethal ventricular arrhythmias remains limited. Despite recent studies evaluating risk stratification tools, there is no optimal strategy. Cardiac imaging provides the opportunity to assess left ventricular ejection fraction, strain, fibrosis, and sympathetic innervation, all of which are pathophysiologically related to SCD risk. These modalities may play a role in the identification of vulnerable anatomic substrates that provide the pathophysiologic basis for SCD. Further studies are required to identify optimal imaging platform for risk assessment.

Atrial Substrate and Triggers of Paroxysmal Atrial Fibrillation in Patients With Obstructive Sleep Apnea.

BACKGROUND: Obstructive sleep apnea (OSA) is associated with atrial remodeling, atrial fibrillation (AF), and increased incidence of arrhythmia recurrence after pulmonary vein (PV) isolation. We aimed to characterize the atrial substrate, including AF triggers in patients with paroxysmal AF and OSA. METHODS AND RESULTS: In 86 patients with paroxysmal AF (43 with ≥moderate OSA [apnea-hypopnea index ≥15] and 43 without OSA [apnea-hypopnea index <5]), right atrial and left atrial voltage distribution, conduction velocities, and electrogram characteristics were analyzed during atrial pacing. AF triggers were examined before and after PV isolation and targeted for ablation. Patients with OSA had lower atrial voltage amplitude (right atrial, P=0.0005; left atrial, P=0.0001), slower conduction velocities (right atrial, P=0.02; left atrial, P=0.0002), and higher prevalence of electrogram fractionation (P=0.0001). The areas of atrial abnormality were consistent among patients, most commonly involving the left atrial septum (32/43; 74.4%). At baseline, the PVs were the most frequent triggers for AF in both groups; however, after PV isolation patients with OSA had increased incidence of additional extra-PV triggers (41.8% versus 11.6%; P=0.003). The 1-year arrhythmia-free survival was similar between patients with and without OSA (83.7% and 81.4%, respectively; P=0.59). In comparison, control patients with paroxysmal AF and OSA who underwent PV isolation alone without ablation on extra-PV triggers had increased risk of arrhythmia recurrence (83.7% versus 64.0%; P=0.003). CONCLUSIONS: OSA is associated with structural and functional atrial remodeling and increased incidence of extra-PV triggers. Elimination of these triggers resulted in improved arrhythmia-free survival.

Atrial fibrillation: Utility of CHADS2 and CHA2DS2-VASc scores as predictors of readmission, mortality and resource utilization.

BACKGROUND: CHADS2 and CHA2DS2-VASc scores are widely used for thromboembolic risk assessment in Atrial Fibrillation(AF) cohort, however further utilization to predict outcomes is understudied. METHOD: HCUP's National Readmission Data(NRD) 2013 was queried for AF admissions using ICD-9-CM code 427.31 in principal diagnosis field. Patients with mitral valve disease or repair/or replacement were excluded to estimate population with non-valvular AF only. CHADS2 and CHA2DS2-VASc were calculated for each patient. Hierarchical two-level logistic and linear models were used to evaluate study outcomes in terms of mortality, 30 or 90-day readmissions, length of stay(LOS) and cost. RESULT: Of 116,450 principal non-valvular AF admissions(50.2% female and 43.1% age≥75years) 29,179 patients were readmitted, with total 40,959 readmissions. Higher CHADS2 and CHA2DS2-VASc score were associated with increased mortality from 0.4% for CHADS2 of 0 to 3.2% for score of 6 and from 0.2% for CHA2DS2-VASc of 0 to 3.2% for score≥8. LOS increased from 2.20days for CHADS2 of 0 to 5.08days for score of 6, while cost increased from $7888 to $11,151. 30-day readmission rate increased from 8.9% for CHADS2 of 0 to 26.0% for score of 6, and 90-day readmission rate increased from 15.2% to 39%. CHA2DS2-VASc scoring similarly demonstrated a trend towards increasing readmission rate, LOS and cost for higher scores. Also, similar results were seen in hierarchical modeling with increment of CHADS2 and CHA2DS2-VASc scores. CONCLUSION: CHADS2 and CHA2DS2-VASc scores can be used as quick surrogate markers for predicting outcomes beyond thromboembolic risk. Physician familiarity with these systems makes them easy to use bedside clinical tools to improve outcomes and resource allocation.

Effects of Transendocardial Stem Cell Injection on Ventricular Proarrhythmia in Patients with Ischemic Cardiomyopathy: Results from the POSEIDON and TAC-HFT Trials.

Transendocardial stem cell injection in patients with ischemic cardiomyopathy (ICM) improves left ventricular function and structure but has ill-defined effects on ventricular arrhythmias. We hypothesized that mesenchymal stem cell (MSC) implantation is not proarrhythmic. Post hoc analyses were performed on ambulatory ECGs collected from the POSEIDON and TAC-HFT trials. Eighty-eight subjects (mean age 61 ± 10 years) with ICM (mean EF 32.2% ± 9.8%) received treatment with MSC (n = 48), Placebo (n = 21), or bone marrow mononuclear cells (BMC) (n = 19). Heart rate variability (HRV) and ventricular ectopy (VE) were evaluated over 12 months. VE did not change in any group following MSC implantation. However, in patients with ≥ 1 VE run (defined as ≥ 3 consecutive premature ventricular complexes in 24 hours) at baseline, there was a decrease in VE runs at 12 months in the MSC group (p = .01), but not in the placebo group (p = .07; intergroup comparison: p = .18). In a subset of the MSC group, HRV measures of standard deviation of normal intervals was 75 ± 30 msec at baseline and increased to 87 ± 32 msec (p =.02) at 12 months, and root mean square of intervals between successive complexes was 36 ± 30 msec and increased to 58.2 ± 50 msec (p = .01) at 12 months. In patients receiving MSCs, there was no evidence for ventricular proarrhythmia, manifested by sustained or nonsustained ventricular ectopy or worsened HRV. Signals of improvement in ventricular arrhythmias and HRV in the MSC group suggest a need for further studies of the antiarrhythmic potential of MSCs. Stem Cells Translational Medicine 2017;6:1366-1372.

Long-term follow-up of patients with paroxysmal atrial fibrillation and severe left atrial scarring: comparison between pulmonary vein antrum isolation only or pulmonary vein isolation combined with either scar homogenization or trigger ablation.

AIMS: Left atrial (LA) scarring, a consequence of cardiac fibrosis is a powerful predictor of procedure-outcome in atrial fibrillation (AF) patients undergoing catheter ablation. We sought to compare the long-term outcome in patients with paroxysmal AF (PAF) and severe LA scarring identified by 3D mapping, undergoing pulmonary vein isolation (PVAI) only or PVAI and the entire scar areas (scar homogenization) or PVAI+ ablation of the non-PV triggers. METHODS AND RESULTS: Totally, 177 consecutive patients with PAF and severe LA scarring were included. Patients underwent PVAI only (n = 45, Group 1), PVAI+ scar homogenization (n = 66, Group 2) or PVAI+ ablation of non-PV triggers (n = 66, Group 3) based on operator's choice. Baseline characteristics were similar across the groups. After first procedure, all patients were followed-up for a minimum of 2 years. The success rate at the end of the follow-up was 18% (8 pts), 21% (14 pts), and 61% (40 pts) in Groups 1, 2, and 3, respectively. Cumulative probability of AF-free survival was significantly higher in Group 3 (overall log-rank P <0.01, pairwise comparison 1 vs. 3 and 2 vs. 3 P < 0.01). During repeat procedures, non-PV triggers were ablated in all. After average 1.5 procedures, the success rates were 28 (62%), 41 (62%), and 56 (85%) in Groups 1, 2, and 3, respectively (log-rank P< 0.001). CONCLUSIONS: In patients with PAF and severe LA scarring, PVAI+ ablation of non-PV triggers is associated with significantly better long-term outcome than PVAI alone or PVAI+ scar homogenization.

Differences Between Access to Follow-Up Care and Inappropriate Shocks Based on Insurance Status of Implantable Cardioverter Defibrillator Recipients.

Differences in implantable cardioverter defibrillator (ICD) utilization based on insurance status have been described, but little is known about postimplant follow-up patterns associated with insurance status and outcomes. We collected demographic, clinical, and device data from 119 consecutive patients presenting with ICD shocks. Insurance status was classified as uninsured/Medicaid (uninsured) or private/Health Maintenance Organization /Medicare (insured). Shock frequencies were analyzed before and after a uniform follow-up pattern was implemented regardless of insurance profile. Uninsured patients were more likely to present with an inappropriate shock (63% vs 40%, p = 0.01), and they were more likely to present with atrial fibrillation (AF) as the shock trigger (37% vs 19%, p = 0.04). Uninsured patients had a longer interval between previous physician contact and index ICD shock (147 ± 167 vs 83 ± 124 days, p = 0.04). Patients were followed for a mean of 521 ± 458 days after being enrolled in a uniform follow-up protocol, and there were no differences in the rate of recurrent shocks based on insurance status. In conclusion, among patients presenting with an ICD shock, underinsured/uninsured patients had significantly longer intervals since previous physician contact and were more likely to present with inappropriate shocks and AF, compared to those with private/Medicare coverage. After the index shock, both groups were followed uniformly, and the differences in rates of inappropriate shocks were mitigated. This observation confirms the importance of regular postimplant follow-up as part of the overall ICD management standard.

Cryoballoon versus Radiofrequency Catheter Ablation in Atrial Fibrillation: A Meta-Analysis.

INTRODUCTION: Radiofrequency (RF) and cryoballoon (CB) catheter ablation are effective for pulmonary vein isolation (PVI) in atrial fibrillation (AF). This report presents an updated meta-analysis comparing the efficacy and safety of CB versus RF ablations in AF. METHODS: Databases and conference abstracts were systematically searched for studies that directly compared CB and RF PVI, and reported safety or efficacy outcomes in follow-up ≥12 months. Recurrent atrial tachyarrhythmias (AT) were defined as AF, atrial flutter, or atrial tachycardia. RESULTS: Twenty-two studies and 8,668 patients were included. Freedom from AT was not significantly different between CB and RF ablations in the pooled population (OR 1.12; 95%CI 0.97-1.29; P = 0.13) and in randomized trials (OR 1.0; 95%CI 0.65-1.56; P = 0.99). Second-generation CB (CB2; 78.1%) and contact-force (CF) sensing RF (78.2%) have improved procedure success rate as compared to first-generation technology (57.9% CB, 58.1% RF). As compared to CF-RF, CB2 demonstrated similar freedom from recurrent AT (OR 1.04; 95%CI 0.71-1.51; P = 0.84). The incidence of pericardial effusions (OR 0.44; 95%CI 0.28-0.69; P < 0.01), tamponade (OR 0.31; 95%CI 0.15-0.64; P < 0.01), and non-AF AT (OR 0.46; 95%CI 0.26-0.83; P < 0.01) were significantly lower with CB ablation, whereas transient phrenic nerve palsy was more incident after CB (OR 7.40; 95%CI 2.56-21.34; P < 0.01). CONCLUSION: There was comparable freedom from AT between CB and RF in patients with AF undergoing PVI. Additionally, freedom from AT was similar between CB2 and CF-RF. However, CB was associated with a lower incidence of pericardial effusions or tamponade, albeit with a higher rate of transient phrenic nerve palsies.

Contemporary utilization and safety outcomes of catheter ablation of atrial flutter in the United States: Analysis of 89,638 procedures.

BACKGROUND: Atrial flutter (AFL) ablation has been increasingly offered as first-line therapy and safely performed over the last decades. However, limited data exist regarding current utilization and trends in adverse outcomes arising from this procedure. OBJECTIVE: The aim of our study was to examine the frequency of adverse events attributable to AFL ablation and influence of hospital volume on safety outcomes. METHODS: Data were obtained from the Nationwide Inpatient Sample, the largest all-payer inpatient dataset in the United States. Patients with AFL who underwent catheter ablation from 2000 to 2011 were identified using ICD-9 codes. In-hospital death and common complications were identified, including cardiac perforation and tamponade, pneumothorax, stroke, transient ischemic attack, and vascular access complications. RESULTS: A total of 89,638 AFL patients were treated with catheter ablation during our study period. Total number of ablations performed increased by 154% from 2000 to 2011. The in-hospital mortality rate was 0.17% and the overall complication rate was 3.17%. Cardiac complications (1.44%) were the most frequent, followed by respiratory (0.88%), vascular (0.78%), and neurological complications (0.05%). Low hospital volume (<50 procedures/year) was significantly associated with increased adverse outcomes. Overall frequency of complications per 100 ablation procedures increased from 2.86 in 2000 to 5.39 in 2011 (P < .001). CONCLUSIONS: The overall complication rate was 3.17% in patients undergoing AFL ablation. There was a significant association between low hospital volume and increased adverse outcomes. This suggests a need for future research into identifying the safety measures in AFL ablations and instituting appropriate interventions to improve overall AFL ablation outcomes.

Trends in Use and Adverse Outcomes Associated with Transvenous Lead Removal in the United States.

BACKGROUND: Transvenous lead removal (TLR) has made significant progress with respect to innovation, efficacy, and safety. However, limited data exist regarding trends in use and adverse outcomes outside the centers of considerable experience for TLR. The aim of our study was to examine use patterns, frequency of adverse events, and influence of hospital volume on complications. METHODS AND RESULTS: Using the Nationwide Inpatient Sample, we identified 91 890 TLR procedures. We investigated common complications including pericardial complications (hemopericardium, cardiac tamponade, or pericardiocentesis), pneumothorax, stroke, vascular complications (consisting of hemorrhage/hematoma, incidents requiring surgical repair, and accidental arterial puncture), and in-hospital deaths described with TLR, defining them by the validated International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code. We specifically assessed in-hospital death (2.2%), hemorrhage requiring transfusion (2.6%), vascular complications (2.0%), pericardial complications (1.4%), open heart surgery (0.2%), and postoperative respiratory failure (2.4%). Independent predictors of complications were female sex and device infections. Hospital volume was not independently associated with higher complications. There was a significant rise in overall complication rates over the study period. CONCLUSIONS: The overall complication rate in patients undergoing TLR was higher than previously reported. Female sex and device infections are associated with higher complications. Hospital volume was not associated with higher complication rates. The number of adverse events in the literature likely underestimates the actual number of complications associated with TLR.

Management of Ventricular Arrhythmias in Patients with Mechanical Ventricular Support Devices.

The use of mechanical ventricular support devices in the management of patients with advanced heart failure continues to increase. These devices have been shown to prolong life as a destination therapy and to increase survival when used as a bridge to transplantation. However, they are associated with a high rate of complications, including bleeding, infection, device malfunction, and ventricular arrhythmias (VAs). The mechanical support provided by the device typically allows for VAs to be well tolerated in the acute setting, though there are numerous long-term complications related to VAs such as ventricular remodeling, right ventricular failure in patients with left ventricular assist devices, and possibly increased mortality. Controversy exists as to the appropriate role of implantable cardioverter defibrillators in these patients. This review will focus on the management options available for patients with mechanical ventricular support devices and VAs.