Catheter ablation for atrial fibrillation can be safely performed without invasive hemodynamic monitoring: A multi-center study.

BACKGROUND: Arterial invasive monitoring is the most common method in the USA for hemodynamic monitoring during atrial fibrillation (AF) ablation. Although studies have shown favorable comparison between non-invasive and invasive hemodynamic monitoring (IHM) in non-cardiac procedures under general anesthesia, limited data is available for complex cardiac procedures such as AF ablation in the USA. With progressive improvement in AF ablation procedural safety, particularly with routine use of intracardiac echocardiography (ICE) to monitor for pericardial effusion, it is unclear if invasive hemodynamic monitoring provides any advantage over non-invasive methods. Therefore, the purpose of this study is to determine whether noninvasive hemodynamic monitoring is non-inferior to invasive hemodynamic monitoring during AF ablation under general anesthesia in patients without major cardiac structural abnormality. METHODS: A multi-center retrospective data of AF ablation from July 2019 to December 2020 was extracted. A total of three hundred and sixty-two patients (362) were included, which were divided into group A (non-invasive hemodynamic monitoring) and group B (invasive hemodynamic monitoring). The primary outcome was to compare procedural safety between the two groups. RESULTS: Out of 362 patients, 184 (51%) received non-invasive and 178 (49%) received invasive hemodynamic monitoring with similar baseline characteristics. There was no significant difference between the two groups in complication rates (groin hematoma, pericardial effusion, cardiac tamponade). Mean procedure time was longer in group B with 3.35% arterial site discomfort. Urgent arterial access was required in only 1 patient in group A. CONCLUSION: This retrospective multicenter study strongly suggests that catheter ablation for atrial fibrillation under general anesthesia can be safely performed with noninvasive hemodynamic monitoring without requiring arterial access, with potential benefit in procedural duration and cost.

Heparin reversal with protamine sulfate is not required in atrial fibrillation ablation with suture hemostasis.

BACKGROUND: The utility of protamine sulfate for heparin reversal in catheter-based atrial fibrillation (AF) ablation is unclear when using the suture closure technique for vascular hemostasis. OBJECTIVE: This study sought to address if protamine sulfate use for heparin reversal reduces vascular access complications in AF catheter ablation when suture techniques are used for postprocedural vascular hemostasis. METHODS: This is a retrospective multicenter observational study of 294 consecutive patients who underwent catheter ablation for AF with subsequent vascular access hemostasis by means of a figure-of-eight suture or stopcock technique. A total of 156 patients received protamine for heparin reversal before sheath removal while 138 patients did not receive protamine. The two groups were compared for procedural activated clotting time (ACT), access site complications, and duration of hospital stay. RESULTS: Baseline demographic characteristics were comparable in both groups. Despite higher ACT before venous sheath removal in patients not receiving protamine (288.0 ± 44.3 vs 153.9 ± 32.0 seconds; P < .001), there was no significant difference in groin complications, postoperative thromboembolic events, or duration of hospital stay between the two groups. Suture failure requiring manual compression was rarely observed in this cohort (0.34%). CONCLUSION: With modern vascular access and sheath management techniques, for patients undergoing catheter ablation for AF, simple suture closure techniques can obviate the need for protamine administration to safely achieve hemostasis after removal of vascular sheaths.

Relation of the Brugada Phenocopy to Hyperkalemia (from the International Registry on Brugada Phenocopy).

Brugada phenocopies (BrPs) are clinical entities that differ in etiology from true congenital Brugada syndrome but have identical electrocardiographic (ECG) patterns. Hyperkalemia is known to be one of the causes of BrP. The aim of this study was to determine the clinical characteristics and evolution of hyperkalemia-induced BrP. Data from 27 cases of hyperkalemia-induced BrP were collected from the International Registry at www.brugadaphenocopy.com. Data were extracted from publications. Of the 27 patients included in the analysis, 18 (67%) were male; mean age was 53 ± 15 years (range 31 to 89). Mean serum potassium concentration was 7.45 ± 0.89 mmol/L. Type-1 Brugada ECG pattern was observed in 21 cases (78%), whereas 6 cases (22%) showed a type-2 Brugada ECG pattern. The Brugada ECG pattern resolved once the hyperkalemia was corrected, with no arrhythmic events. Estimated time to resolution was 7 ± 3 hours. In 4 cases (16%), a concurrent metabolic abnormality was detected: 3 (11%) presented with acidosis, 2 (7%) with hyponatremia, 1 (4%) with hypocalcaemia, 1 (4%) with hyperphosphatemia, and 1 (4%) with hyperglycemia. In 7 cases (26%), provocative testing using sodium channel blockers was performed, and all failed to reproduce a BrS ECG pattern (BrP class A). Additionally, no sudden cardiac death or malignant ventricular arrhythmias were detected. Hyperkalemia was found a common cause of BrP in our International Registry. The Brugada ECG pattern appears to occur at high serum potassium concentrations (>6.5 mmol/L). The ECG normalizes within hours of correcting the electrolyte imbalance. Importantly, hyperkalemia-induced BrP has not been associated with sudden cardiac death or ventricular arrhythmia.

Angiographic Efficacy of the Atriclip Left Atrial Appendage Exclusion Device Placed by Minimally Invasive Thoracoscopic Approach.

OBJECTIVES: This study sought to assess long-term left atrial appendage (LAA) closure efficacy of the Atriclip applied via totally thoracoscopic (TT) approach with computed tomographic angiography. BACKGROUND: LAA closure is associated with a low risk for atrial fibrillation-related embolic stroke. The Atriclip exclusion device allows epicardial LAA closure, avoiding the need for post-operative oral anticoagulation. Previous data with Atriclip during open chest procedures show a high efficacy rate of closure >95%. METHODS: Three-dimensional volumetric 2-phase computed tomographic angiography ≥90 days post-implantation was independently assessed by chest radiology for complete LAA closure on all consented subjects identified retrospectively as having had a TT-placed Atriclip at Vanderbilt University Medical Center from June 13, 2011, to October 6, 2015. RESULTS: Complete LAA closure (defined by complete exclusion of the LAA with no exposed trabeculations, and clip within 1 cm from the left circumflex artery) was found in 61 of 65 subjects (93.9%). Four cases had incomplete closure (6.2%). Two clips were placed too distally, leaving a large stump with exposed trabeculae. Two clips failed to address a secondary LAA lobe. No major complications were associated with TT placement of the Atriclip. Follow-up over 183 patient-years revealed 1 stroke in a patient with complete LAA closure and no thrombus (hypertensive cerebrovascular accident). CONCLUSIONS: Angiographic LAA closure efficacy with a TT-placed Atriclip is high (93.9%). The clinical significance of a remnant stump is unknown. Confirmation of complete LAA occlusion should be made before cessation of systemic anticoagulation.

Measurement of diffuse ventricular fibrosis with myocardial T1 in patients with atrial fibrillation.

BACKGROUND: Atrial fibrillation (AF) is associated with cardiac fibrosis, which can now be measured noninvasively using T1-mapping with cardiac magnetic resonance imaging (CMRI). This study aimed to assess the impact of AF on ventricular T1 at the time of CMRI. METHODS: Subjects with AF scheduled for AF ablation underwent CMRI with standard electrocardiography gating and breath-hold protocols on a 1.5 T scanner with post-contrast ventricular T1 recorded from 6 regions of interest at the mid-ventricle. Baseline demographic, clinical, and imaging characteristics were examined using univariate and multivariable linear regression modeling for an association with myocardial T1. RESULTS: One hundred fifty-seven patients were studied (32% women; median age, 61 years [interquartile range {IQR}, 55-67], 50% persistent AF [episodes>7 days or requiring electrical or pharmacologic cardioversion], 30% in AF at the time of the CMRI). The median global T1 was 404 ms (IQR, 381-428). AF at the time of CMRI was associated with a 4.4% shorter T1 (p=0.000) compared to sinus rhythm when adjusted for age, sex, persistent AF, body mass index, congestive heart failure, and renal dysfunction (estimated glomerular filtration rate<60). A post-hoc multivariate model adjusted for heart rate suggested that heart rate elevation (p=0.009) contributes to the reduction in T1 observed in patients with AF at the time of CMRI. No association between ventricular T1 and AF recurrence after ablation was demonstrated. CONCLUSION: AF at the time of CMRI was associated with lower post-contrast ventricular T1 compared with sinus rhythm. This effect was at least partly due to elevated heart rate. T1 was not associated with the recurrence of AF after ablation.