Background: Inflammation is integral in the pathogenesis and propagation of atrial fibrillation (AF). Peri-ablation administration of steroids has been shown to significantly reduce AF recurrence at 3 months. We sought to determine the effect of intraoperative dexamethasone on early recurrence at both 3 months and 12 months post-ablation. Methods: A cohort of 94 adult patients (>18 years) underwent catheter ablation at Mayo Clinic Rochester from January to March 2019. Only first-time ablation patients were included, with all re-do ablations excluded to minimize heterogeneity. Administration of intraoperative dexamethasone 4 mg or 8 mg was determined by chart review from the procedure. At our institution, intraoperative intravenous steroids are administered for postoperative nausea and vomiting (PONV) prophylaxis at the discretion of the anesthesiologist. AF recurrence was determined by ECG or cardiac monitoring at less than 3 months or between 3 months and 1 year with an in-person follow-up visit. Results: A total of 36.2% of patients received intravenous dexamethasone compared to 63.8% who did not (providing a 2:1 comparison group). The incidence of documented AF or flutter lasting greater than 30 seconds was 20.6% in the dexamethasone group versus 21.7% in the non-dexamethasone group, p value 1.00. AF or atrial flutter recurrence from 3 months to 1 year was 20.6% in the dexamethasone group compared to 21.7% in the non-dexamethasone group, p value 1.00. Conclusion: These data suggest that intraoperative intravenous dexamethasone administered during AF ablation for postoperative nausea and vomiting prophylaxis does not have a significant effect on AF recurrence rates.

Background: New-onset atrial fibrillation (NOAF) in COVID-19 raises significant clinical and public health issues. This systematic review and meta-analysis aims to compile and analyze the current literature on NOAF in COVID-19 and give a more comprehensive understanding of the prevalence and outcomes of NOAF in COVID-19. Methods: A comprehensive literature search was carried out using several databases. The random effect model using inverse variance method and DerSimonian and Laird estimator of Tua2 was used to calculate the pooled prevalence and associated 95% confidence interval (CI). Results for outcome analysis were presented as odds ratios (ORs) with 95% CI and pooled using the Mantel-Haenszel random-effects model. Results: The pooled prevalence of NOAF in COVID-19 was 7.8% (95% CI, 6.54% to 9.32%), pooled estimate from 30 articles (81,929 COVID-19 patients). Furthermore, our analysis reported that COVID-19 patients with NOAF had a higher risk of developing severe disease compared with COVID–19 patients without a history of atrial fibrillation (OR= 4.78, 95% CI 3.75 to 6.09) and COVID-19 patients with a history of pre-existing atrial fibrillation (OR= 2.75, 95% CI 2.10 to 3.59) . Similarly, our analysis also indicated that COVID–19 patients with NOAF had a higher risk of all-cause mortality compared with, COVID–19 patients without a history of atrial fibrillation (OOR= 3.83, 95% CI 2.99 to 4.92) and COVID-19 patients with a history of pre-existing atrial fibrillation (OR= 2.32, 95% CI 1.35 to 3.96). The meta-analysis did not reveal any significant publication bias. Conclusion: The results of the current meta-analysis a high prevalence rate of NOAF among COVID-19 patients. Further the study reported higher disease severity with NOAF compared with COVID-19 patients without a history of atrial fibrillation and with a history of atrial fibrillation.

The prevalence of atrial fibrillation (AF) is forecasted to increase manifold, emphasizing the need for efficacious treatments. Pulmonary vein isolation (PVI) to eliminate ectopic triggers is now established as a fundamental component of the invasive treatment of AF, however its efficacy in persistent AF remains suboptimal. The atrial myocardium undergoes adverse fibrotic remodeling as AF progresses, favoring arrhythmia initiation and maintenance. Reductions in left atrial bipolar voltage have been suggested to identify regions of such pathological remodeling, and represent novel targets for ablation to target the arrhythmogenic substrate. Early observational studies targeting these low voltage areas (LVA) have been encouraging, however results from more recent randomized trials are more mixed. Importantly, there is significant heterogeneity in the techniques for identifying LVAs and the strategies for ablation. In reality, the atrial arrhythmogenic substrate is multi-faceted rather than being limited to fibrosis and there remains uncertainty as to how accurately LVAs represent regions of fibrosis. Additionally, bipolar voltage is influenced by numerous physiological and biophysical factors. The present review summarizes the current evidence for LVA ablation in AF. We then analyze the components of the atrial arrhythmic substrate, its relationship to LVAs and the limitations in LVA assessment. Finally we discuss novel techniques for delineating the atrial substrate.

The preprocedural imaging before the left atrial appendage closure device is critical for selecting the appropriate device for the appropriate patient. CT scans and TEE have been used in the past for preprocedural imaging. In this report, the authors used cardiac MRI as a pre procedural planning tool in the wake of scarcity of contrast availability.

Aims: The MicraTM transcatheter pacing system (TPS) (Medtronic) is the only leadless pacemaker that promotes atrioventricular (AV) synchrony via accelerometer-based atrial sensing. Data regarding the real-world experience with this novel system are currently lacking. We sought to characterize patients undergoing MicraTM -AV implants, describe percentage AV synchrony achieved, and analyze the causes for suboptimal AV synchrony. Methods: In this retrospective cohort study, electronic medical records from 56 consecutive patients undergoing MicraTM -AV implants at the Mayo Clinic sites in Minnesota, Florida, and Arizona with a minimum follow-up of 3 months were reviewed. Demographic data, comorbidities, echocardiographic data, and clinical outcomes were compared among patients with and without atrial synchronous-ventricular pacing (AsVP) ≥70%. Results: Fifty-six percent of patients achieved AsVP ≥70%. Patients with adequate AsVP had smaller body mass indices, a lower proportion of congestive heart failure and pulmonary hypertension. Echocardiographic parameters and procedural characteristics were similar across the two groups. Active device troubleshooting was associated with higher AsVP. The likely reasons for low AsVP were persistent atrial arrhythmias, small A4-wave amplitude, and inadequate device reprogramming. Importantly, in patients with low AsVP, subjective clinical worsening was not noted during follow-up. Conclusion: With the increasing popularity of leadless PM, it is paramount for device implanting teams to be familiar with common predictors of AV synchrony and troubleshooting with MicraTM -AV devices.

Title: Gradual prolongation of PR interval followed by a pause. What’s the mechanism?

Catheter ablation for atrial fibrillation has emerged as a main stay for management of atrial fibrillation. It has been shown to be clinically effective and cost effective in multiple trials .

Background: Data regarding ventricular tachycardia (VT) or premature ventricular complex (PVC) ablation following MVS is limited.) CA can be challenging given perivalvular substrate in the setting of mitral annuloplasty or prosthetic valves. Objective: To investigate the characteristics, safety, and outcomes of radiofrequency catheter ablation (CA) in patients with prior mitral valve surgery (MVS) and ventricular arrhythmias (VA). Methods: We identified consecutive patients with prior MVS who underwent CA for VT or PVC between January 2013- December 2018. We investigated the mechanism of arrhythmia, ablation approach, peri-operative complications, and outcomes. Results: In our cohort of 31 patients (77% men, mean age 62.3±10.8 years, left ventricular ejection fraction 39.2±13.9%) with prior MVS underwent CA (16 VT; 15 PVC). Access to the left ventricle was via transseptal approach in 17 patients, and a retrograde aortic approach was used in 13 patients. A combined transseptal and retrograde aortic approach was used in one patient, and a percutaneous epicardial approach was combined with trans-septal approach in 1patient. Heterogenous scar regions were present in 94% of VT patients and scar-related reentry was the dominant mechanism of VT. Clinical VA substrates involved the peri-mitral area in 6 patients with VT and 5 patients with PVC ablation. No procedure-related complications were reported. The overall recurrence-free rate at 1-year was 72.2%; 67% in the VT group and 78% in the PVC group. No arrhythmia-related death was documented on long-term follow-up. Conclusion: CA of VAs can be performed safely and effectively in patients with MVS

Ultrasound guided venous access Is important to minimize pneumothorax and unnecessary incisions in patients undergoing device implant.

Background: The improved life expectancy observed in patients living with Human Immunodeficiency Virus (HIV) infection has made age-related cardiovascular complications, including arrhythmias, a growing health concern. We describe the temporal trends in frequency of various arrhythmias and assess impact of arrhythmias on hospitalized HIV patients using the Nationwide Inpatient Sample (NIS) Methods and Results: Data on HIV-related hospitalizations from 2005 to 2014 were obtained from the NIS using International Classification of Diseases, 9th Revision (ICD-9) codes. Data was further subclassified into hospitalizations with associated arrhythmias and those without arrhythmia. Baseline demographics and comorbidities were determined. Outcomes including in-hospital mortality, cost of care, and length of stay were extracted. SAS 9.4 (SAS Institute Inc., Cary, North Carolina) was utilized for analysis. A multivariable analysis was performed to identify predictors of arrhythmias among hospitalized HIV patients. Among 2,370,751 HIV-related hospitalizations identified, the overall frequency of any arrhythmia was 3.01%. Atrial fibrillation (AF) was the most frequent arrhythmia (2110 per 100,000). The overall frequency of arrhythmias has increased over time by 108%, primarily due to a 132% increase in AF. Arrhythmias are more frequent among older males, lowest income quartile and non-elective admissions. Patients with arrhythmias had a higher in-hospital mortality rate (9.6%). In-hospital mortality among patients with arrhythmias has decreased over time by 43.8%. The cost of care and length of stay associated with arrhythmia-related hospitalizations were mostly unchanged. Conclusions: Arrhythmias are associated with significant morbidity and mortality in hospitalized HIV patients. AF is the most frequent arrhythmia in hospitalized HIV patients.