Acute Kidney Injury Resulting From Hemoglobinuria After Pulsed-Field Ablation in Atrial Fibrillation: Is it Preventable?

BACKGROUND: High-voltage pulses can cause hemolysis. OBJECTIVES: The authors evaluated the occurrence of hemoglobinuria after pulsed-field ablation (PFA) and its impact on renal function in patients with atrial fibrillation (AF). METHODS: A consecutive series of patients with AF undergoing PFA were included in this analysis. The initial patients who did not receive postablation hydration immediately after the procedure were classified as group 1 (n = 28), and the rest of the study patients who received planned fluid infusion (0.9% sodium chloride ≥2 L) after the procedure were categorized as group 2 (n = 75). RESULTS: Of the 28 patients in group 1, 21 (75%) experienced hemoglobinuria during the 24 hours after catheter ablation. The mean postablation serum creatinine (S-Cr) was significantly higher than the baseline value in those 21 patients (1.46 ± 0.28 mg/dL vs 0.86 ± 0.24 mg/dL, P < 0.001). Of those 21 patients, 4 (19%) had S-Cr. >2.5 mg/dL (mean: 2.95 ± 0.21 mg/dL). The mean number of PF applications was significantly higher in those 4 patients than in the other 17 patients experiencing hemoglobinuria (94.63 ± 3.20 vs 46.75 ± 9.10, P < 0.001). In group 2 patients, no significant changes in S-Cr were noted. The group 2 patients received significantly higher amounts of fluid infusion after catheter ablation than did those in group 1 (2,082.50 ± 258.08 mL vs 494.01 ± 71.65 mL, P < 0.001). In multivariable analysis, both hydration (R2 = 0.63, P < 0.01) and number of PFA applications (R2 = 0.33, P < 0.01) were independent predictors of postprocedure acute kidney injury. CONCLUSIONS: On the basis of our findings, both the number of PFA applications and postablation hydration were independent predictors of renal insult that could be prevented using planned fluid infusion immediately after the procedure.

Pulsed-Field Ablation Does Not Worsen Baseline Pulmonary Hypertension Following Prior Radiofrequency Ablations.

BACKGROUND: Studies have reported development of pulmonary hypertension (PH) secondary to reduced LA compliance following AF ablation. OBJECTIVES: We aimed to compare the risk of worsening of baseline PH between non-paroxysmal AF patients undergoing pulsed-field ablation (PFA) and standard radiofrequency ablation (RFA). METHODS: This multicenter study included 28 nonparoxysmal AF patients with PH undergoing a PFA-based ablation procedure after >1 failed RFA. A cohort of 28 AF patients with PH, scheduled for repeat RFA, 1:1 propensity-score matched using a multivariable logistic model, were used as the comparator group. Right heart catheterization and echocardiography were performed before and after the procedure to assess the pulmonary artery pressure (PAP). PH was defined as resting mean PAP of >20 mm Hg. RESULTS: The baseline characteristics of the PFA and propensity-matched RFA groups were comparable. The mean PAP assessments at baseline, follow-up, and change from baseline were analyzed. The groups had comparable baseline mean pulmonary artery pressures (mPAP) (P = 0.177). After adjustment for baseline mPAP in an analysis of covariance model, the least-squares means change at 3 months after ablation was -1.71 ± 1.03 mm Hg and 19.67 ± 1.03 mm Hg in PFA and RFA, respectively (P <0.001). CONCLUSIONS: In this propensity-matched population, no worsening of mPAP was detected following pulsed-field ablation in patients with pre-existing PH undergoing a repeat procedure for recurrence.

Catheter ablation approach and outcome in HIV+ patients with recurrent atrial fibrillation.

INTRODUCTION: Earlier studies have shown a clear association between severity of human immunodeficiency virus (HIV) infection and incident atrial fibrillation (AF). We present the long-term outcome of catheter ablation (CA) and electrophysiological characteristics in HIV+ AF patients. METHODS: This study evaluated 1438 consecutive AF patients [31 (2.15%) with HIV and 1407 (97.8%) without HIV diagnosis] undergoing their first CA at our center. A total of 31 HIV patients and 31 controls were generated by propensity matching, based on calculated risk factor scores, using a logistic model. During first procedure, all received isolation of pulmonary vein (PV) + posterior wall and superior vena cava. Non-PV triggers, defined as ectopic triggers originating from sites other than PVs, were identified at the redo ablation with high-dose isoproterenol challenge. RESULTS: Clinical characteristics were not different between the groups. When compared to the control, by the end of 5 years after the first procedure, recurrence was significantly greater in HIV group [100% vs. 54%, p < .001]. Among patients that underwent redo ablation non-PV triggers were higher in HIV group [93.5% vs. 54%, p < .001], and most frequently originated from the coronary sinus [67.7% vs. 45.2%, p < .001] and left atrial appendage [41.9% vs. 25.8%, p < .001]. After focal ablation of non-PV trigger, no difference in arrhythmia recurrence between two groups [80.6% vs. 87.1%, p = .753] at 1-year follow up was found. CONCLUSION: Our findings suggest that non-PV triggers are highly prevalent in HIV+ AF patients resulting in higher rate of the mid- and long-term arrhythmia recurrence.

Impact of Colchicine Monotherapy on the Risk of Acute Pericarditis Following Atrial Fibrillation Ablation.

BACKGROUND: Acute pericarditis is a known complication of ablation procedures for atrial fibrillation (AF). OBJECTIVES: This study aimed to evaluate the benefits of colchicine monotherapy in terms of reducing the risk of pericarditis and related hospitalization rate in AF patients undergoing catheter ablation. METHODS: Consecutive AF patients undergoing first catheter ablation were classified into 3 groups based on their colchicine use: Group 1: no colchicine; group 2: colchicine from 7 days before to 1 month after ablation; and group 3: colchicine from the day of the procedure to 1 month after. Standard institutional protocol was used to follow all patients for 1 year. RESULTS: A total of 1,075 patients were classified into groups 1 (n = 607), 2 (n = 213), and 3 (n = 255). Symptoms of acute pericarditis were reported in 129 patients (12%): group 1: n = 106 (17.5%); group 2: n = 4 (1.9%); and group 3: n = 19 (7.5%); P < 0.001. Rate of mild-moderate as well as severe pericarditis were significantly lower in group 2. In the multivariable regression analysis, pre- and post-ablation colchicine use was seen to be associated with significantly lower risk of acute pericarditis and related hospitalization compared with the other 2 groups. In addition, at 1-year follow-up, arrhythmia-free survival rate was significantly higher in paroxysmal AF patients receiving colchicine compared with the no-colchicine population. CONCLUSIONS: Colchicine therapy starting 7 days before to 1 month after the ablation procedure was associated with significantly lower risk of acute pericarditis and related hospitalization. In addition, paroxysmal AF patients receiving colchicine had a higher arrhythmia-free survival rate compared with those not receiving colchicine.

Best ablation strategy in patients with premature ventricular contractions with multiple morphology: a single-centre experience.

AIMS: This study aimed to examine the clinical benefits of targeted ablation of all Premature ventricular complex (PVC) morphologies vs. predominant PVC only. METHODS AND RESULTS: A total of 171 consecutive patients with reduced left ventricular ejection fraction (LVEF) and ≥2 PVC morphology with high burden (>10%/day) undergoing their first ablation procedure were included in the analysis. At the initial procedure, prevalent PVC alone was ablated in the majority. However, at the redo, all PVC morphologies were targeted for ablation. : At the first procedure, 152 (89%) patients received ablation of the dominant PVC only. In the remaining 19 (11%) patients, all PVC morphologies were ablated. At two years, high PVC burden was detected in 89 (52%) patients. Repeat procedure was performed in 78 of 89, where all PVC morphologies were ablated. At 5 years after the repeat procedure, 71 (91%) had PVC burden of <5% [3.8 ± 1.1% vs. 15.4 ± 4.3% in successful vs. failed subjects (P < 0.001)]. In patients with low PVC burden after the initial procedure, LVEF improved from 37.5% to 41.6% [mean difference (MD): 3.39 ± 2.9%, P < 0.001], whereas a reduction in LVEF from 39.8% to 34.5% (MD: 6.45 ± 4.7%, P < 0.001) was recorded in patients with high PVC burden. One year after the repeat procedure, LVEF improved from 36.2% to 41.7% (MD: 5.5 ± 4.3%, P < 0.001) in patients with successful ablation. CONCLUSION: In this observational series, ablation of all PVC morphologies was associated with significantly lower PVC burden and improvement of LVEF at long-term follow-up, compared with ablation of the dominant morphology only.

Prevalence of atrial fibrillation and procedural outcome in patients undergoing catheter ablation for premature ventricular complexes.

INTRODUCTION: Atrial fibrillation (AF) and premature ventricular complexes (PVC) are common arrhythmias. We aimed to investigate AF prevalence in patients with PVC and its impact on PVC ablation outcomes. METHODS: Consecutive patients undergoing PVC ablation at a single institution between 2016 and 2019 were included and prospectively followed for 2 years. Patients with severe valvular heart disease, hyperthyroidism, malignancy, alcohol use disorder and advanced renal/hepatic diseases were excluded. Twelve-lead electrocardiograms were used to diagnose AF and assess PVC morphology. All PVCs were targeted for ablation using 4-mm irrigated-tip catheters at standardized radiofrequency power guided by 3-D mapping and intracardiac echocardiography. Patients were followed with remote monitoring, device interrogations and office visits every 6 months for 2 years. Detection of any PVCs in follow-up was considered as recurrence. RESULTS: A total of 394 patients underwent PVC ablation and 96 (24%) had concurrent AF. Patients with PVC and AF were significantly older (68.2 ± 10.8 vs. 58.3 ± 15.8 years, p < .001), had lower LV ejection fraction (43.3 ± 13.3% vs. 49.6 ± 12.4%, p < .001), higher CHA2 DS2 -VASc (2.8 ± 1.3 vs. 2.0 ± 1.3, p < .001) than those without. PVCs with ≥2 morphologies were detected in 60.4% and 13.7% patients with vs without AF (p < .001). At 2-year follow-up, PVC recurrence rate was significantly higher in patients with vs without AF (17.7% vs. 9.4%, p = .02). CONCLUSION: AF was documented in 1/4 of patients undergoing PVC ablation and was associated with lower procedural success at long-term follow-up. This was likely attributed to older age, worse LV function and higher prevalence of multiple PVC morphologies in patients with concurrent AF.

Impact of digital monitoring on compliance and outcome of lifestyle-change measures in patients with coexistent atrial fibrillation and obesity.

Introduction: Obesity, a known risk factor for atrial fibrillation (AF), is potentially reversible through lifestyle changes, including diet and physical activity. However, lack of compliance is a major obstacle in attaining sustained weight loss. We investigated the impact of patient engagement using a digital monitoring system on compliance for lifestyle-change measures and subsequent outcome. Methods: A total of 105 consecutive patients with coexistent AF and obesity (body mass index ≥28) were classified into 2 groups based on the monitoring method: group 1, use of digital platform (n = 20); group 2, conventional method (n = 85). Group 1 used the RFMx digital monitoring platform (smartphone app) that sets weekly goals for exercise and weight loss, tracks patient compliance data continuously, and sends regular text reminders. Conventional method included monitoring patients' adherence to diet and change in weight during in-person clinic visits or monthly phone calls from staff. Results: Baseline characteristics of groups 1 and 2 were comparable. At 6 months of follow-up, 12 (60%) and 28 (33%) from group 1 and 2, respectively, were compliant with the physician instructions regarding diet and exercise (P = .025). Weight loss was observed in 9 of 12 (75%) from group 1 and 11 of 28 (39%) from group 2 (P = .038) and mean reduction in weight was 9.9 ± 8.9 lb and 4.0 ± 2.1 lb (P = .042). Conclusion: In this series, continuous digital monitoring was seen to be associated with significant improvement in compliance through better patient engagement, resulting in more weight loss compared to the conventional method.

Endocardial Scar-Homogenization With vs Without Epicardial Ablation in VT Patients With Ischemic Cardiomyopathy.

OBJECTIVES: In this study, the authors investigated the ablation success of scar homogenization with combined (epicardial + endocardial) vs endocardial-only approach for ventricular tachycardia (VT) in patients with ischemic cardiomyopathy (ICM) at 5 years of follow-up. BACKGROUND: Best ablation approach to achieve long-term success rate in VT patients with ICM is not known yet. METHODS: Consecutive ICM patients undergoing VT ablation at our center were classified into group 1: endocardial + epicardial scar homogenization and group 2: endocardial scar homogenization. Patients with previous open heart surgery were excluded. Epicardial ablation was performed despite being noninducible after endocardial ablation in all group 1 patients. All patients underwent bipolar substrate mapping with standard scar settings defined as normal tissue >1.5 mV and severe scar <0.5 mV. Noninducibility of monomorphic VT was the procedural endpoint in both groups. Patients were followed up every 4 months for 5 years with implantable device interrogations. RESULTS: A total of 361 patients (group 1: n = 70 and group 2: n = 291) were included in the study. At 5 years, 81.4% (n = 57/70) patients from group 1 and 66.3% (n = 193/291) from group 2 were arrhythmia-free (P = 0.01) Of those patients, 26 of 57 (45.6%) and 172 of 193 (89.1%) from group 1 and group 2 respectively were on anti-arrhythmic drugs (AAD) (log-rank P < 0.001). After adjusting for age, sex, and obstructive sleep apnea, endo-epicardial scar homogenization was associated with a significant reduction in arrhythmia-recurrence (HR: 0.48; 95% CI: 0.27-0.86; P = 0.02). CONCLUSIONS: In this series of patients with ICM and VT, epicardial substrate was detected in all group 1 patients despite being noninducible after endocardial ablation. Moreover, combined endo-epicardial scar homogenization was associated with a significantly higher success rate at 5 years of follow-up and a substantially lower need for antiarrhythmic drugs after the procedure compared with the endocardial ablation alone.

Coronavirus Disease-19 Testing Strategies for Patients and Health Care Workers to Improve Workplace Safety.

Tests to detect active viral infection and related immune response in the staff and patients attending health care facilities effectively identified positive cases presenting with or without symptoms of coronavirus disease (COVID)-19. Subsequent home isolation of these contagious cases helped curb the chance of the spread of infection at the workplace. Furthermore, serologic tests conducted postvaccination facilitated the detection of individuals with poor immune response following active immunization that would likely require further safety measures to protect themselves from contracting the infection in health care facilities.

Recovery of Conduction Following High-Power Short-Duration Ablation in Patients With Atrial Fibrillation: A Single-Center Experience.

[Figure: see text].

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.

Natural History of Arrhythmia After Successful Isolation of Pulmonary Veins, Left Atrial Posterior Wall, and Superior Vena Cava in Patients With Paroxysmal Atrial Fibrillation: A Multi-Center Experience.

Background We evaluated long-term outcome of isolation of pulmonary veins, left atrial posterior wall, and superior vena cava, including time to recurrence and prevalent triggering foci at repeat ablation in patients with paroxysmal atrial fibrillation with or without cardiovascular comorbidities. Methods and Results A total of 1633 consecutive patients with paroxysmal atrial fibrillation that were arrhythmia-free for 2 years following the index ablation were classified into: group 1 (without comorbidities); n=692 and group 2 (with comorbidities); n=941. We excluded patients with documented ablation of areas other than pulmonary veins, the left atrial posterior wall, and the superior vena cava at the index procedure. At 10 years after an average of 1.2 procedures, 215 (31%) and 480 (51%) patients had recurrence with median time to recurrence being 7.4 (interquartile interval [IQI] 4.3-8.5) and 5.6 (IQI 3.8-8.3) years in group 1 and 2, respectively. A total of 201 (93.5%) and 456 (95%) patients from group 1 and 2 underwent redo ablation; 147/201 and 414/456 received left atrial appendage and coronary sinus isolation and 54/201 and 42/456 had left atrial lines and flutter ablation. At 2 years after the redo, 134 (91.1%) and 391 (94.4%) patients from group 1 and 2 receiving left atrial appendage/coronary sinus isolation remained arrhythmia-free whereas sinus rhythm was maintained in 4 (7.4%) and 3 (7.1%) patients in respective groups undergoing empirical lines and flutter ablation (P<0.001). Conclusions Very late recurrence of atrial fibrillation after successful isolation of pulmonary veins, regardless of the comorbidity profile, was majorly driven by non-pulmonary vein triggers and ablation of these foci resulted in high success rate. However, presence of comorbidities was associated with significantly earlier recurrence.

Impact of Oral Anticoagulation Therapy Versus Left Atrial Appendage Occlusion on Cognitive Function and Quality of Life in Patients With Atrial Fibrillation.

Background We compared the cognitive status and quality of life in patients with atrial fibrillation undergoing left atrial appendage occlusion (LAAO) or remaining on oral anticoagulation (OAC) after atrial fibrillation ablation. Methods and Results Cognition was assessed by the Montreal Cognitive Assessment (MoCA) survey at baseline and follow-up. Consecutive patients receiving LAAO or OAC after atrial fibrillation ablation were screened, and patients with a score of ≤17 were excluded from the study. Quality of life was measured at baseline and 1 year using the Atrial Fibrillation Effect on Quality of Life survey. A total of 50 patients (CHA2DS2-VASc [congestive heart failure, hypertension, age≥75 years, diabetes mellitus, stroke or transient ischemic attack, vascular disease, age 65-74 years, sex category] score: 3.30±1.43) in the LAAO group and 48 (CHA2DS2-VASc score 2.73±1.25) in the OAC group were included in this prospective study. Mean baseline MoCA score was 26.18 and 26.08 in the LAAO and OAC groups, respectively (P=0.846). At 1 year, scores were 26.94 and 23.38 in the respective groups. MoCA score decreased by an estimated -2.74 (95% CI, -3.61 to -1.87; P<0.0001) points in the OAC group, whereas the change in the LAAO group was nonsignificant (0.79; (95% CI, -0.06 to 1.64; P=0.07). After adjusting for baseline clinical characteristics, remaining on OAC was an independent predictor of MoCA change at 1 year (regression coefficient, -3.38; 95% CI, -4.75 to -2.02; P<0.0001). Change in Atrial Fibrillation Effect on Quality of Life score did not differ significantly in achieving a clinically important difference between groups. Conclusions In this series, a significant difference in the postprocedure MoCA score was observed in postablation patients with atrial fibrillation receiving LAAO versus remaining on OAC with a substantial decline in the score in the OAC group. However, quality of life improved similarly across groups. Registration https://www.ClinicalTrials.gov. Unique identifier: NCT01816308.

Predictors of recurrent atrial fibrillation following catheter ablation.

INTRODUCTION: Atrial fibrillation (AF) is a complex and multi-factorial rhythm disorder. Catheter ablation is widely used for the management of AF. However, it is limited by relapse of the arrhythmia necessitating repeat procedures. AREAS COVERED: This review aims to discuss the predictors of post-ablation recurrent AF including age, gender, genetic predisposition, AF type and duration, comorbidities, lifestyle factors, echocardiographic parameters of heart chambers, left atrial fibrosis and ablation strategies and targets. An extensive literature search was undertaken on PubMed and Google Scholar to obtain full texts of relevant AF-related articles. EXPERT OPINION: Maintenance of stable sinus rhythm is the main intended outcome of AF ablation. Therefore, it is very crucial to identify the risk factors that may influence the ablation success. Most of these predictors such as comorbidities, ablation strategy and targets and lifestyle factors are either reversible or modifiable. Thus, not only the awareness of these known risk factors by both patients and their physicians but also future research to identify the unknown predictors are critical to optimize care in this multi-faceted morbidity.

Arrhythmia profile and ablation-outcome in elderly women with atrial fibrillation undergoing first catheter ablation.

BACKGROUND: This study evaluated the arrhythmia profile and ablation outcome in women with atrial fibrillation (AF) aged ≥75 years. METHODS: A total of 573 consecutive female patients undergoing first AF ablation were classified into group 1: ≥75 years (n = 221) and group 2: < 75 years (n = 352). Isolation of PVs, posterior wall and superior vena cava was performed in all. Non-PV triggers from other areas were ablated based on operator's discretion. RESULTS: Group 1 had higher prevalence of hypertension (154 (69.7%) vs. 188 (53.4%), p < .001) and non-paroxysmal AF (136 (61.5%) vs. 126 (35.8%), p < .001). Non-PV triggers were detected in 194 (87.8%) patients from group 1 and 143 (40.6%) from group 2 (p < .001) and were ablated in 152 (68.8%) and 114 (32.4%) from group 1 and 2 respectively. Remaining patients (group 1: 69/221 and group 2: 238/352) received no additional ablation. At 4 years, 109 (49.3%) and 185 (52.6%) from group 1 and 2, respectively, were arrhythmia-free, p = .69. When stratified by ablation-strategy, success-rate was similar across groups in patients receiving non-PV trigger ablation (96 (63.2%) in group 1 and 76 (66.7%) in group 2, p = .61), whereas it was significantly lower in group 1 patients not receiving additional ablation compared to those from group 2 (13 (18.8%) vs. 109 (45.8%), p < .001). CONCLUSION: Non-paroxysmal AF was more common in women aged ≥75 years. Furthermore, significantly higher number of non-PV triggers were detected in elderly women and ablation of those provided similar ablation success as that in women aged < 75 years.

Thromboembolic Risk in Atrial Fibrillation Patients With Left Atrial Scar Post-Extensive Ablation: A Single-Center Experience.

OBJECTIVES: This study evaluated the association of the post-ablation scar with stroke risk in patients undergoing atrial fibrillation (AF) ablation. BACKGROUND: Late gadolinium enhancement-cardiac magnetic resonance studies have reported a direct association between pre-ablation left atrial scar and thromboembolic events in patients with AF. METHODS: Consecutive patients with AF were classified into 2 groups based on the type of ablation performed at the first procedure. Group 1 involved limited ablation (isolation of pulmonary veins, left atrial posterior wall, and superior vena cava); and group 2 involved extensive ablation (limited ablation + ablation of nonpulmonary vein triggers from all sites except left atrial appendage). During the repeat procedure, post-ablation scar (region with bipolar voltage amplitude <0.5 mV) was identified by using 3-dimensional voltage mapping. RESULTS: A total of 6,297 patients were included: group 1, n = 1,713; group 2, n = 4,584. Group 2 patients were significantly older and had more nonparoxysmal AF. Nineteen (0.3%) thromboembolic events were reported after the first ablation procedure: 9 (1.02%) in group 1 and 10 (0.61%) in group 2 (p = 0.26). At the time of the event, all 19 patients were experiencing arrhythmia. Median time to stroke was 14 (interquartile range: 9 to 20) months in group 1 and 14.5 (interquartile range: 8 to 18) months in group 2. Post-ablation scar data were derived from 2,414 patients undergoing repeat ablation. Mean scar area was detected as 67.1 ± 4.6% in group 2 and 34.9 ± 8.8% in group 1 at the redo procedure (p < 0.001). CONCLUSIONS: Differently from the cardiac magnetic resonance-detected pre-ablation scar, scar resulting from extensive ablation was not associated with increased risk of stroke compared with that from the limited ablation.

Half-normal saline versus normal saline for irrigation of open-irrigated radiofrequency catheters in atrial fibrillation ablation.

BACKGROUND: The creation of effective and permanent lesions is a crucial factor in determining the success rate of atrial fibrillation (AF) ablation. By increasing the efficacy of radiofrequency (RF) energy-mediated lesion formation, half-normal saline (HNS) as an irrigant for open-irrigated ablation catheters has the potential to reduce procedural times and improve acute and long-term outcomes. METHODS: This is a double-blind randomized clinical trial of 99 patients undergoing first-time RF catheter ablation for AF. Patients enrolled were randomly assigned in a 1:1 fashion to perform ablation using HNS or normal saline (NS) as an irrigant for the ablation catheter. RESULTS: The use of HNS is associated with shorter RF times (26 vs. 33 min; p = .02) with comparable procedure times (104 vs. 104 min). The rate of acute pulmonary vein reconnections (16% vs. 18%) was comparable, with a median of 1 vein reconnection in the HNS arm versus 2 in the NS arm. There was no difference in procedure-related complications, including the incidence of postprocedural hyponatremia when using HNS. Over the 1-year follow-up, there is no significant difference between the HNS and NS with respect to the recurrence of any atrial arrhythmia (off antiarrhythmic drugs [AAD]: 47% vs. 52%; hazard ratio [HR]: 1.17, 95% confidence interval [CI]: 0.66-2.06; off/on AAD: 66% vs. 66%, HR: 1.06, 95% CI: 0.53-2.12), with a potential benefit of using HNS when considering the paroxysmal AF cohort (on/off AAD 73% vs. 62%, HR: 0.72, 95% CI: 0.19-2.70). CONCLUSIONS: In a mixed cohort of patients undergoing first-time AF ablation, irrigation of open-irrigated RF ablation catheters with HNS is associated with shorter RF times, with a comparably low rate of procedure-related complications. In the long term, there is no significant difference with respect to the recurrence of any atrial arrhythmia. Larger studies with a more homogeneous population are necessary to determine whether HNS improves clinical outcomes.

Creating a safe workplace by universal testing of SARS-CoV-2 infection in asymptomatic patients and healthcare workers in the electrophysiology units: a multi-center experience.

BACKGROUND: As the coronavirus cases continue to surge, the urgent need for universal testing to identify positive cases for effective containment of this highly contagious pandemic has become the center of attention worldwide. However, in spite of extensive discussions, very few places have even attempted to implement it. We evaluated the efficacy of widespread testing in creating a safe workplace in our electrophysiology (EP) community. Furthermore, we assessed the new infection rate in patients undergoing EP procedure, to see if identification and exclusion of positive cases facilitated establishment of a risk-free operating environment. METHODS: Viral-RNA and serology tests were conducted in 1670 asymptomatic subjects including patients and their caregivers and staff in our EP units along with the Emergency Medical Service (EMS) staff. RESULTS: Of 1670, 758 (45.4%) were patients and the remaining 912 were caregivers, EMS staff, and staff from EP clinic and lab. Viral-RNA test revealed 64 (3.8%) positives in the population. A significant increase in positivity rate was observed from April to June 2020 (p = 0.02). Procedures of positive cases (n = 31) were postponed until they tested negative at retesting. Staff testing positive (n = 33) were retested before going back to work after 2 weeks. Because of suspected exposure, 67 staff were retested and source was traced. No new infections were reported in patients during or within 2 weeks after the hospital-stay. CONCLUSIONS: Universal testing to identify positive cases was helpful in creating and maintaining a safe working environment without exposing patients and staff to new infections in the EP units. TRIAL REGISTRATION: Trial Registration Number: clinicaltrials.gov : NCT04352764.

A simple method to detect leaks after left atrial appendage occlusion with Watchman.

BACKGROUND: We evaluated the efficacy of a new method in identifying peri-device leak (PDL) using morphology of the thrombus formed inside the left atrial appendage (LAA) as seen on follow-up transesophageal echo (TEE). METHOD: A total of 291 consecutive patients undergoing Watchman procedure were included in this analysis. TEE was performed at 45 days postprocedure. Based on the presence of the thrombus inside the LAA behind the device, patients were grouped as (1) white (W) group: LAA completely filled with thrombus (n = 101), 2) nonwhite (NW) group: LAA completely black or mixed (part black and part white; n = 190). Follow-up TEE was repeated at 6 and 12 months. RESULTS: Baseline characteristics were comparable between groups except the device size, number of patients with chicken-wing morphology, and prevalence of left atrial "smoke" that were significantly higher in the NW group. Detection of black appearance was comparable between the pre-coil closure image and the NW population (26/36 [72.2%] vs 99/154 [64.3%], p = .37). After adjusting for clinically relevant covariates, NW appearance of the LAA was associated with the presence of significant leak (odds ratio: 47.96, 95% confidence interval: 2.91-790.2, p < .001). The 11 patients with mixed appearance at the 6-month TEE remained unchanged (part black and part white) at the 12-month TEE. LAA appearance was white in all 36 patients following coil closure. CONCLUSION: Our findings demonstrated white and nonwhite appearance of the appendage on TEE to be reliable markers of complete closure and leak respectively, following LAA occlusion with the Watchman device.