Case report:peri-device leakage after percutaneous left atrial appendage occlusion: plug, clip, or amputate?

BACKGROUND: Although peri-device leakage is frequently observed after left atrial appendage occlusion (LAAO), there is no consensus on the optimal management strategy. It is unknown whether additional plugging should be preferred over surgical exclusion of the LAA, as experience with additional plugging is limited. CASE SUMMARY: In this case report, we demonstrate the clinical implications of additional plugging and surgical exclusion in a 65-year-old male patient with peri-device leakage and recurrent thromboembolic events. After the recurrence of paroxysmal atrial fibrillation (AF) and a transient ischaemic attack despite adequate anticoagulation, the patient was opted for re-do pulmonary vein isolation and LAAO with a Watchman device. Due to multiple ischaemic strokes and recurrent AF in combination with significant peri-device leakage, additional plugging with a second device was performed. Post-procedurally, the patient had another ischaemic stroke and persisting peri-device leakage was observed during follow-up. Due to progressive symptoms of AF and patient’s preference to discontinue DOAC, he underwent a Cox MAZE IV procedure, including amputation of the LAA with both devices. Within six months after surgery, the patient experienced two more ischaemic events. In the following two years, the patient remained free of any cerebrovascular accidents or recurrence of AF. DISCUSSION: Additional plugging of peri-device leakage is not always successful in stroke prevention. In combination with recurrent AF, progressive symptoms, contraindication for oral anticoagulation, and patient’s preference, surgical LAA exclusion could be preferred over additional plugging

Detection of endo-epicardial atrial low-voltage areas using unipolar and omnipolar voltage mapping

Background: Low-voltage areas (LVA) can be located exclusively at either the endocardium or epicardium. This has only been demonstrated for bipolar voltages, but the value of unipolar and omnipolar voltages recorded from either the endocardium and epicardium in predicting LVAs at the opposite layer remains unknown. The goal of this study was therefore to compare simultaneously recorded endo-epicardial unipolar and omnipolar potentials and to determine whether their voltage characteristics are predictive for opposite LVAs. Methods: Intra-operative simultaneous endo-epicardial mapping (256 electrodes, interelectrode distances 2 mm) was performed during sinus rhythm at the right atrium in 93 patients (67 ± 9 years, 73 male). Cliques of four electrodes (2 × 2 mm) were used to define maximal omnipolar (V(omni,max)) and unipolar (V(uni,max)) voltages. LVAs were defined as V(omni,max) ≤0.5 mV or V(uni,max) ≤1.0 mV. Results: The majority of both unipolar and omnipolar LVAs were located at only the endocardium (74.2% and 82.0% respectively) or epicardium (52.7% and 47.6% respectively). Of the endocardial unipolar LVAs, 25.8% were also located at the opposite layer and 47.3% vice-versa. In omnipolar LVAs, 18.0% of the endocardial LVAs were also located at the epicardium and 52.4% vice-versa. The combination of epicardial V(uni,max) and V(omni,max) was most accurate in identifying dual-layer LVAs (50.4%). Conclusion: Unipolar and omnipolar LVAs are frequently located exclusively at either the endocardium or epicardium. Endo-epicardial LVAs are most accurately identified using combined epicardial unipolar and omnipolar voltages. Therefore, a combined endo-epicardial unipolar and omnipolar mapping approach is favoured as it may be more indicative of possible arrhythmogenic substrates

Characterization of pre-existing arrhythmogenic substrate associated with de novo early and late postoperative atrial fibrillation

Background: PoAF is the most common complication after cardiac surgery and may occur in patients with pre-existing arrhythmogenic substrate. Characterization of this substrate could aid in identifying patients at risk for PoAF. We therefore compared intra-atrial conduction parameters and electrogram morphology between patients without and with early- (≤5 days after surgery) and late- (up to 5 years) postoperative atrial fibrillation (PoAF). Methods and results: Epicardial mapping of the right and left atrium and Bachmann's Bundle (BB) was performed during sinus rhythm (SR) in 263 patients (207male, 67 ± 11 years). Unipolar potentials were classified as single, short or long double and fractionated potentials. Unipolar voltage, fractionation delay (time difference between the first and last deflection), conduction velocity (CV) and conduction block (CB) prevalence were measured. Comparing patients without (N = 166) and with PoAF (N = 97), PoAF was associated with lower CV and more CB at BB. Unipolar voltages were lower and more low-voltage areas were found at the left and right atrium and BB in PoAF patients. These differences were more pronounced in patients with late-PoAF (6%), which could even occur up to 5 years after surgery. Although several electrophysiological parameters were related to PoAF, age was the only independent predictor. Conclusions: Patients with de novo PoAF have more extensive arrhythmogenic substrate prior to cardiac surgery compared to those who remained in SR, which is even more pronounced in late-PoAF patients. Future studies should evaluate whether intra-operative electrophysiological examination enables identification of patients at risk for developing PoAF and hence (preventive) therapy.</p

A randomized prospective multicenter trial for stroke prevention by prophylactic surgical closure of the left atrial appendage in patients undergoing bioprosthetic aortic valve surgery--LAA-CLOSURE trial protocol

Patients undergoing surgical aortic valve replacement (SAVR) are at high risk for atrial fibrillation (AF) and stroke after surgery. There is an unmet clinical need to improve stroke prevention in this patient population. The LAA-CLOSURE trial aims to assess the efficacy and safety of prophylactic surgical closure of the left atrial appendage for stroke and cardiovascular death prevention in patients undergoing bioprosthetic SAVR. This randomized, open-label, prospective multicenter trial will enroll 1,040 patients at 13 European sites. The primary endpoint is a composite of cardiovascular mortality, stroke and systemic embolism at 5 years. Secondary endpoints include cardiovascular mortality, stroke, systemic embolism, bleed fulfilling academic research consortium (BARC) criteria, hospitalization for decompensated heart failure and health economic evaluation. Sample size is based on 30% risk reduction in time to event analysis of primary endpoint. Prespecified reports include 30-daysafety analysis focusing on AF occurrence and short-term outcomes and interim analyses at 1 and 3 years for primary and secondary outcomes. Additionally, substudies will be performed on the completeness of the closure using transesophageal echocardiography/cardiac computed tomography and long-term ECG recording at one year after the operation. (Am Heart J 2021;237:127-134.

How sex affects the sinus rhythm heartbeat

Background: There is increasing awareness of sex-specific differences in epidemiology and pathophysiology of atrial fibrillation (AF). It is, however, unknown whether males and females differ in atrial electrophysiological properties during sinus rhythm (SR). The aim of this study was therefore to investigate sex-based (regional) differences in electrophysiological properties during SR of the right (RA) and left (LA) atrium including Bachmanns Bundle (BB) and pulmonary vein region (PVA). Methods: Intra-operative, high resolution mapping during SR was performed in 53 matched females with males (without a history of AF), to measure lines of conduction block (CB), continuous conduction delay and block (cCDCB), conduction velocities (CV), total atrial activation times (TAT), unipolar potential voltages and percentage of low voltage areas (LVA). Results: Compared to males, females have significantly 1) lower unipolar potential voltages and slower CV at both RA and BB, 2) more LVAs, CB and cCDCB lines and longer CB and cCDCB lines at the RA only (all P &lt; 0.05). Conclusions: Electrophysiological properties of the atria during SR differ between males and females. These sex-based differences are particularly present at the RA and to a lesser degree at BB. In females, both the RA and BB contained more areas of conduction disorders and low voltage potentials. Future studies are required to investigate whether these areas play a role in sex-based differences in vulnerability to arrhythmias such as atrial fibrillation.</p

Immersive 3D Virtual Reality–Based Clip Sizing for Thoracoscopic Left Atrial Appendage Closure

Objective: Surgical left atrial appendage (LAA) closure using epicardial clips has become popular in stroke prevention in patients with atrial fibrillation. Optimal placement of the clip is essential to achieve complete LAA occlusion and to prevent complications due to compression of the circumflex artery. We determine the added value of immersive virtual reality (VR) in accurately assessing LAA base size and selection of an appropriately sized clip. Methods: We studied the feasibility of measuring the LAA base using VR and conventional computed tomography (CT). A retrospective analysis was performed of LAA base measurements in 15 patients who had undergone thoracoscopic LAA clipping. Subsequently, we compared the placed clip size with imaging-acquired LAA base size to retrospectively evaluate intraprocedural sizing. Results: We successfully applied a VR platform to measure LAA base size. The median LAA base size measured in CT (23.8 mm, interquartile range [IQR] 22.3 to 26.4 mm) and intracardial virtual reality (23.4 mm, IQR 21.6 to 25.5 mm) did not differ significantly (P = 0.416). VR measurements of the LAA base in surgeon's view (25.7 mm, IQR 24.2 to 29.2) were significantly higher than those of 2-dimensional CT (P = 0.037) and intracardial 3-dimensional (3D) VR (P < 0.05) measurements. All measurements differed significantly with placed clip sizes (P < 0.05). There were no clip malpositioning-related events. Conclusions: Immersive VR is a feasible method for obtaining anatomical information on LAA base size. In this retrospective analysis, CT and VR-based measurements of LAA base size differed significantly from intraoperatively placed LAA clips, indicating potential oversizing when measured intraoperatively. Using intuitive 3D VR-based imaging might be a useful method to assist in accurate preprocedural sizing of LAA base and can potentially prevent oversizing

Unipolar atrial electrogram morphology is affected by age: evidence from high-resolution epicardial mapping

Background: It is unknown which features of unipolar atrial electrogram (U-AEGM) morphology are affected by ageing and whether age-related changes in U-AEGM morphology are equally distributed throughout the right and left atria. Patients and methods: Epicardial high-resolution mapping was performed in patients undergoing coronary artery bypass grafting surgery during sinus rhythm (SR). Mapping areas include the right atrium (RA), left atrium (LA), pulmonary vein area (PVA) and Bachmann’s bundle (BB). Patients were categorized into a young (age 15ms) and fractionated potentials (FPs, ≥3 deflections). Results: A total of 213 patients (age: 67 (59–73) years; young group N = 58, aged group N = 155) were included. Only at BB, the proportion of SPs (p = 0.007) was significantly higher in the young group, while the proportion of SDPs (p = 0.051), LDPs (p = 0.004) and FPs (p = 0.006) was higher in the aged group. After adjusting for potential confounders, older age was associated with a reduction in SPs [regression coefficient (β): −6.33, 95% confident interval (CI): −10.37 to −2.30] at the expense of an increased proportion of SDPs (β: 2.49, 95% CI: 0.09 to 4.89), LDPs (β: 1.94, 95% CI: 0.21 to 3.68) and FPs (β: 1.90, 95% CI: 0.62 to 3.18). Conclusions: Age-related remodeling particularly affects BB as indicated by the decreased amount of non-SP at this location in the elderly.Key Messages Ageing preferentially affects the morphology of unipolar atrial electrograms recorded at Bachmann’s bundle. At Bachmann’s bundle, the proportion of short double-, long double- and fractionated potentials increase during ageing at the expense of a decrease in the proportion of single potentials, reflecting aggravation of abnormalities in conduction. The increase in abnormal unipolar atrial electrograms at Bachmann’s bundle during ageing supports the concept that Bachmann’s bundle may play an important role in development of age-related arrhythmias such as atrial fibrillation

Atrial electrophysiological characteristics of aging

Introduction: Advancing age is a known risk factor for developing atrial fibrillation (AF), yet it is unknown which electrophysiological changes contribute to this increased susceptibility. The goal of this study is to investigate conduction disturbances and unipolar voltages (UV) related to aging. Methods: We included 216 patients (182 male, age: 36–83 years) without a history of AF undergoing elective coronary artery bypass surgery. Five seconds of sinus rhythm were recorded intraoperatively at the right atrium (RA), Bachmann's bundle (BB), the left atrium and the pulmonary vein area (PVA). Conduction delay (CD), -block (CB), -velocity (CV), length of longest CB lines and UV were assessed in all regions. Results: With aging, increasing conduction disturbances were found, particularly at RA and BB (RA: longest CB line rs =.158, p =.021; BB: CB prevalence rs =.206, p =.003; CV rs = −.239, p <.0005). Prevalence of low UV areas (UV <5th percentile) increased with aging at the BB and PVA (BB: rs =.237, p <.0005 and PVA: rs =.228, p =.001). Conclusions: Aging is accompanied by an increase in conduction disturbances during sinus rhythm and a higher prevalence of low UV areas, particularly at BB and in the RA. These electrophysiological alterations could in part explain the increasing susceptibility to AF development associated with aging