New insights into the clinical signs of supraventricular tachycardia: The "sign of lace-tying".

BACKGROUND: Supraventricular tachycardias (SVT) are a common arrhythmia therefore an accurate diagnosis is of clinical importance. Although an ECG performed during tachycardia greatly aids diagnosis, patient history and predisposing factors also improve diagnostic accuracy. METHODS: This prospective study included 100 consecutive patients undergoing electrophysiological study for SVT with the aim to reassess their clinical characteristics and describe frequent predisposing factors, such as the "sign of lace-tying" that to our knowledge has not previously been reported. Each patient completed an extensive questionnaire (70 questions) during their hospital stay. RESULTS: Our series comprised: 67% of patients with atrioventricular nodal reentrant tachycardia (AVNRT); 24% with an accessory pathway; and 9% presented atrial tachycardia. Half of the population were male and 29% of the cohort presented hypertension. Syncope during tachycardia appeared in 15% of patients, dizziness in 52% and thoracic pain in 59%. We encountered a predisposing risk factor for SVT in 53% of cases; with 32% exhibiting an anteflexion of the trunk termed the "sign of lace-tying." Data also showed that younger patients tended to present AVRT and regular pounding in the neck appeared only in patients with AVNRT. CONCLUSIONS: Overall, our study has highlighted the importance of considering clinical signs and patient characteristics both before and during SVT for the precise diagnosis of paroxysmal SVT. Furthermore, 32% of patients presented the "sign of lace-tying" or body position change before SVT, implying a diagnosis of SVT.

Integrity of the Ganglionated Plexi Is Essential to Parasympathetic Innervation of the Atrioventricular Node by the Right Vagus Nerve.

INTRODUCTION: Radiofrequency isolation of pulmonary vein can be accompanied by transient sinus bradycardia or atrioventricular nodal (AVN) block, suggesting an influence on vagal cardiac innervation. However, the importance of the atrial fat pads in relation with the vagal innervation of AVN in humans remains largely unknown. The aim of this study was to evaluate the role of ganglionated plexi (GP) in the innervation of the AVN by the right vagus nerve. METHODS AND RESULTS: Direct epicardial high-frequency stimulation (HFS) of the GP (20 patients) and the right vagus nerve (10 patients) was performed before and after fat pad exclusion or destruction in 20 patients undergoing thoracoscopic epicardial ablation for the treatment of persistent AF. Asystole longer than 3 seconds or acute R-R prolongation over 25% was considered as a positive response to HFS. Prior to the ablation, positive responses to HFS were detected in 3 GPs in 7 patients (35%), 2 GPs in 5 patients (25%), and one GP in 8 patients (40%). After exclusion of the fat pads, all patients had a negative response to HFS. All the patients who exhibited a positive response to right vagus nerve stimulation (n = 10) demonstrated negative responses after the ablation. CONCLUSION: The integrity of the GP is essential for the right vagus nerve to exert physiological effects of on AVN in humans.

Method, safety, and outcomes of persistent AF ablation without a circular mapping catheter: 3 years experience of a Belgian Tertiary Centre.

BACKGROUND: We aimed to share our methods and experience of persistent AF ablation without a circular mapping catheter (CMC), thereby avoiding femoral venous and transseptal punctures, decreasing the cost of the procedure, and possibly reducing the duration of the procedure and fluoroscopy time. METHODS: We report our experience with 261 persistent AF ablations performed without a CMC over the past 3 years. RESULTS: The procedures were performed with no apparent loss of efficacy or safety. Freedom from recurrence was defined as a 1-year absence of AF/atrial flutter (AFL) episodes >30 s, beyond the 3-month blanking period. At 1 year, 72% of the patients were free from arrythmias. CONCLUSIONS: Persistent AF ablation is feasible without a CMC, reducing the need for venous and transseptal punctures and the cost of the procedure. We suggest that prospective studies should aim to characterise the reduction in procedure and fluoroscopy times as a result of this technique.

Predictive value of thromboembolic risk scores before an atrial fibrillation ablation procedure.

INTRODUCTION: It is not clear whether transesophageal echocardiography (TEE) should be performed prior to a planned atrial fibrillation (AF) ablation in all patients. METHODS AND RESULTS: The objectives of this study were to determine in 681 consecutive patients: (i) the relationship between the CHADS2 and CHA2DS2-VASc scores, the presence of a thrombogenic milieu and left atrial (LA) volume; (ii) the need for TEE in patients with low and intermediate thromboembolic risk assessed; and (iii) the predictive accuracy of the these 2 scores for the presence of thrombi in the LA/LAA (LA appendage) before a planned AF ablation. The prevalence of thrombi was 1%. All patients with thrombi had LA dilatation, a CHADS2 score ≥ 1 and a CHA2DS2-VASc score ≥ 2. CHADS2 or CHA2DS2-VASc scores <2 had an almost maximal negative predictive capability of excluding the presence of a thrombus (99.8% and 100%, respectively; 95% CI: 99-100). A CHADS2 score ≥ 2 had a sensitivity and specificity of 86% (95% CI: 42-100) and 82% (95% CI: 79-85), respectively, to predict the presence of a thrombus in the LA/LAA, while a CHA2DS2-VASc score ≥ 2 had a sensitivity and specificity of 100% (95% CI: 59-100) and 67% (95% CI: 63-70). The area under the curve for CHADS2 and CHA2DS2-VASc scores ≥ 2 was 0.928 (95% CI: 0.906-0.946) and 0.933 (95% CI: 0.912-0.951), respectively. CONCLUSION: Not all patients undergoing planned endocardial pulmonary vein isolation need preprocedural TEE. Both scores <2 had an almost maximal negative predictive capability of excluding the presence of a thrombus in the LA/LAA.

Intravenous adenosine to predict conduction recurrence in cavotricuspid isthmus early after ablation of typical atrial flutter: myth or reality?

INTRODUCTION: Early recovery of conduction (ER) after cavotricuspid isthmus (CTI) ablation for typical atrial flutter (AFl) occurs in approximately 10% of the patients. If not recognized, ER might lead to AFl recurrences. In this study, we hypothesized that intravenous adenosine (iADO) can be used to predict ER in the CTI immediately after RF ablation and distinguish functional block from the complete destruction of the CTI myocardium. METHODS: We prospectively included 68 consecutive patients (age: 65 ± 14 years; male: 78%) referred in our centers for AFl ablation. Immediately after bidirectional isthmus block validation, a bolus of iADO was given during continuous pacing from the proximal coronary sinus. Patients with functional block revealed under iADO (iADO+) and those without (iADO-) were subsequently observed for a 30-minute waiting period (ER-) or until sustained recovery of the conduction through the CTI (ER+). RESULTS: Seven patients presented a persistent recovery (ER+, 10.3%, mean time to recovery: 14 ± 9 minutes). None of them presented even a transient resumption of conduction under iADO (iADO+: 0). With univariate analysis, we identified a heavy patient weight (>95 kg) as a predictor of ER (sensitivity: 71%). CONCLUSIONS: Adenosine does not predict early recovery in the CTI after linear ablation for atrial flutter. We found that a patient weight over 95 kg predicted early recovery of conduction through the CTI with a sensitivity of 71%.

Exercise intolerance due to sustained atrial bigeminy with short coupling interval.

Atrial bigeminy is a supraventricular arrhythmia rarely associated with severe symptoms. We report the case of a 22-year-old woman with no prior cardiac disease presenting with exercise intolerance since several months. No apparent heart disease other than a spontaneous conducted atrial bigeminy with a short coupling interval was found. At bicycle ergometric testing, symptoms occurred, because of an inadequate increase in pulse rate, due to sustained atrial bigeminy. At electrophysiological study, an ectopic atrial focus at the right atrial septum was successfully ablated.

A circular mapping catheter is not mandatory for isolating pulmonary veins during paroxysmal atrial fibrillation ablation with radiofrequency.

PURPOSE: In this study, we evaluated the feasibility, efficacy, and safety of radiofrequency ablation of paroxysmal atrial fibrillation (AF) with the use of an ablation catheter only (non-CMC group) by retrospectively comparing its procedural success and recurrence rates at 1 year to ablation performed with the help of a circular mapping catheter (CMC group). METHODS: We compared the success and recurrence rates between 226 patients and 251 patients who underwent index ablation with and without the use of CMC, respectively. RESULTS: Freedom from recurrence was defined as a 1-year absence of AF/atrial tachycardia (AT) episodes > 30 s, beyond the 3-month blanking period. There was no significant difference between the number of pulmonary vein isolations, recurrence rate of AF/AT, and the use of antiarrhythmic drugs after 1 year of ablation. The procedure and fluoroscopy times were lower in the non-CMC group compared with the CMC group (106 ± 33 vs. 125 ± 32 min, p < 0.0001; 2.2 ± 1.9 vs. 2.7 ± 2.3 min, p = 0.0002, respectively). CONCLUSIONS: Pulmonary vein isolation without the use of a CMC is feasible; moreover, the material costs, procedure time, and radiation exposure were reduced compared with the CMC group. Freedom of recurrence was similar between groups. Optimized use of 3D electro-anatomical mapping systems could reduce the radiation exposure for both the patient and physician.

3D navigation system allows remarkable reduction in fluoroscopy use during cavo-tricuspid isthmus ablation.

PURPOSE: Typical atrial flutter (AFL) is one of the most common supraventricular arrhythmias. Its treatment mainly relies on cavo-tricuspid isthmus (CTI) ablation, which can be performed either using conventional fluoroscopy, still mainly used, or 3D navigation system to track the position of the catheter. The aim of this study is to show that the use of a 3D navigation system allows a dramatic reduction of fluoroscopy use during CTI ablation, without any loss of efficacy, time, or safety. METHODS: In this single-center study, we retrospectively compared 134 cases of CTI ablation performed for typical AFL without a 3D navigation system with 95 cases of CTI ablation performed with such a 3D system. We compared the rates of procedural success (defined as obtaining a bidirectional electrical conduction block), freedom from AFL recurrence at 1-year follow-up, procedural time and safety, and fluoroscopy use. RESULTS: Compared to conventional fluoroscopy, the use of a 3D navigation system significantly decreased the duration of fluoroscopy use (2 min 13 s ± 2 min 16 s versus 14 min 41 s ± 10 min 39 s, p < 0.0001) and dose-area products (1567.9 ± 1329.5 mGy cm2 versus 8263.3 ± 8636.6 mGy cm2, p < 0.0001). Procedure success rates, duration, and safety were not different between groups. CONCLUSIONS: The use of 3D navigation during CTI ablation substantially reduces fluoroscopy use duration, without reducing the success rates and safety or prolonging the procedure duration, as compared to conventional fluoroscopy. We therefore suggest the generalization of this navigation system.

Assessment of low plasma concentrations of apixaban in the periprocedural setting.

INTRODUCTION: Estimation of residual apixaban plasma concentrations may be requested in the management of emergencies. This study aims at assessing the performance of specific anti-Xa assays calibrated with apixaban on real-life samples with low apixaban plasma concentrations (<30 ng/mL) and on-treatment ranges, with and without interference of low-molecular-weight heparin (LMWH). METHODS: The performance of the STA® -Liquid Anti-Xa assay (STA® LAX) and the low and normal procedures of the Biophen® Direct Factor Xa Inhibitors (DiXaI) assay was tested on 134 blood samples, collected from patients on apixaban, wherefrom 74 patients received LMWH after apixaban cessation. The results were compared with the liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) measurements. RESULTS: The Biophen® DiXaI, Biophen® DiXaI LOW, and STA® LAX showed very good correlation with LC-MS/MS measurements in patients without LMWH administration (Spearman r .95, .99, and .98, respectively). Their limits of quantitation were defined at 48, 24, and 12 ng/mL, respectively. The Bland-Altman test measured mean bias (SD) at 5.6 (13.1), -2.5 (5.0), and -0.8 (6.1) ng/ml, respectively. The Spearman r of the Biophen® DiXaI decreased to 0.64 in presence of low apixaban concentrations. The Spearman r of the Biophen® DiXaI LOW and STA® LAX decreased to 0.39 and 0.26, respectively, in presence of LMWH. CONCLUSIONS: The accuracy of the low methodologies (Biophen® DiXaI LOW and STA® LAX) is slightly improved for low apixaban plasma concentrations, compared with the normal procedure of Biophen® DiXaI. The interference of LMWH on the low methodologies is measurable, however, less important than the previously reported interference of LMWH on rivaroxaban calibrated specific anti-Xa assays.

Variable morphologies of preexcitation due to a concomitant Brugada pattern.

Since the first publication of the Brugada syndrome in 1992 several variants of this ECG pattern have been described. We report a very unusual case of preexcitation with changing electrocardiographic morphologies which appeared to be an association of a variable Brugada pattern with a persistent antegrade preexcitation.