Matthias Antz

Complete Isolation of Left Atrium Surrounding the Pulmonary Veins New Insights From the Double-Lasso Technique in Paroxysmal Atrial Fibrillation

Background—Paroxysmal atrial fibrillation (PAF) can be eliminated with continuous circular lesions (CCLs) around the pulmonary veins (PVs), but it is unclear whether all PVs are completely isolated. Methods and Results—Forty-one patients with symptomatic PAF underwent 3D mapping, and all PV ostia were marked on the 3D map based on venography. Irrigated radiofrequency energy was applied at a distance from the PV ostia guided by 2 Lasso catheters placed within the ipsilateral superior and inferior PVs. The mean radiofrequency duration was 1550±511 seconds for left-sided PVs and 1512±506 seconds for right-sided PVs. After isolation, automatic activity was observed in the right-sided PVs in 87.8% and in the left-sided PVs in 80.5%. During the procedure, a spontaneous or induced PV tachycardia (PVT) with a cycle length of 189±29 ms was observed in 19 patients. During a mean follow-up of 6 months, atrial tachyarrhythmias recurred in 10 patients. Nine patients underwent a repeat procedure. Conduction gaps in the left CCL in 9 patients and in the right CCL in 2 patients were closed during the second procedure. A spontaneous PVT with a cycle length of 212±44 ms was demonstrated in 7 of 9 patients, even though no PVT had been observed in 6 of these 7 patients during the first procedure. No AF recurred in 39 patients after PV isolation during follow-up. Conclusions—Automatic activity and fast tachycardia within the PVs could reflect an arrhythmogenic substrate in patients with PAF, which could be eliminated by isolating all PVs with CCLs guided by 3D mapping and the double-Lasso technique in the majority of patients.

European Heart Rhythm Association Practical Guide on the use of new oral anticoagulants in patients with non-valvular atrial fibrillation.

New oral anticoagulants (NOACs) are an alternative for vitamin K antagonists (VKAs) to prevent stroke in patients with non-valvular atrial fibrillation (AF). Both physicians and patients will have to learn how to use these drugs effectively and safely in clinical practice. Many unresolved questions on how to optimally use these drugs in specific clinical situations remain. The European Heart Rhythm Association set out to coordinate a unified way of informing physicians on the use of the different NOACs. A writing group listed 15 topics of concrete clinical scenarios and formulated as practical answers as possible based on available evidence. The 15 topics are: (1) Practical start-up and follow-up scheme for patients on NOACs; (2) How to measure the anticoagulant effect of NOACs; (3) Drug-drug interactions and pharmacokinetics of NOACs; (4) Switching between anticoagulant regimens; (5) Ensuring compliance of NOAC intake; (6) How to deal with dosing errors; (7) Patients with chronic kidney disease; (8) What to do if there is a (suspected) overdose without bleeding, or a clotting test is indicating a risk of bleeding? (9) Management of bleeding complications; (10) Patients undergoing a planned surgical intervention or ablation; (11) Patients undergoing an urgent surgical intervention; (12) Patients with AF and coronary artery disease; (13) Cardioversion in a NOAC-treated patient; (14) Patients presenting with acute stroke while on NOACs; (15) NOACs vs. VKAs in AF patients with a malignancy. Since new information is becoming available at a rapid pace, an EHRA Web site with the latest updated information accompanies this text (www.NOACforAF.eu).

Recovered Pulmonary Vein Conduction as a Dominant Factor for Recurrent Atrial Tachyarrhythmias After Complete Circular Isolation of the Pulmonary Veins Lessons From Double Lasso Technique

Background—Atrial tachyarrhythmias (ATa) can recur after continuous circular lesions (CCLs) around the ipsilateral pulmonary veins (PVs) in patients with atrial fibrillation (AF). This study characterizes the electrophysiological findings in patients with and without ATa after complete PV isolation. Methods and Results—Twenty-nine of 100 patients had recurrent ATa after complete PV isolation by use of CCLs during a mean follow-up of ≈8 months. A repeat procedure was performed in 26 patients with ATa and in 7 volunteers without ATa at 3 to 4 months after CCLs. No recovered PV conduction was demonstrated in the 7 volunteers, whereas recovered PV conduction was found in 21 patients with recurrent ATa (right-sided PVs in 9 patients and left-sided PVs in 16 patients). The interval from the onset of the P wave to the earliest PV spike was 157±66 ms in the right-sided PVs and 149±45 ms in the left-sided PVs. During the procedure, PV tachycardia activated the atrium and resulted in atrial tachycardia (AT) in 10 patients. All conduction gaps were successfully closed with segmental RF ablation. After PV isolation, macroreentrant AT was induced and ablated in 3 patients. In the 5 patients without PV conduction, focal AT in the left atrial roof in 2 patients and non-PV foci in the left atrium in 1 patient were successfully abolished; in the remaining 2 patients, no ablation was performed because of noninducible arrhythmias. During a mean follow-up of ≈6 months, 24 patients were free of ATa without antiarrhythmic drugs. Conclusions—In patients with recurrent ATa after CCLs, recovered PV conduction is a dominant finding in ≈80% of patients and can be successfully eliminated by segmental RF ablation. Also, mapping and ablation of non-PV arrhythmias can improve clinical success.

Repetitive monomorphic ventricular tachycardia originating from the aortic sinus cusp: electrocardiographic characterization for guiding catheter ablation.

OBJECTIVES We sought to investigate the electrocardiographic (ECG) characteristics for guiding catheter ablation in patients with repetitive monomorphic ventricular tachycardia (RMVT) originating from the aortic sinus cusp (ASC). BACKGROUND Repetitive monomorphic ventricular tachycardia can originate from the right ventricular outflow tract (RVOT) and ASC in patients with a left bundle branch block (LBBB) morphology and an inferior axis. METHODS Activation mapping and ECG analysis was performed in 15 patients with RMVT or ventricular premature contractions. The left main coronary artery (LMCA) was cannulated as a marker and for protection during radiofrequency delivery if RMVT originated from the left coronary ASC. RESULTS During arrhythmia, the earliest ventricular activation was recorded from the superior septal RVOT in eight patients (group 1) and from the ASC in the remaining seven patients (group 2). The indexes of R-wave duration and R/S-wave amplitude were significantly lower in group 1 than in group 2 (31.8+/-13.5% vs. 58.3+/-12.1% and 14.9+/-9.9% vs. 56.7+/-29.5%, respectively; p < 0.01), despite similar QRS morphology. In five patients from group 2, RMVT originated from the left ASC, with a mean distance of 12.2+/-3.2 mm (range 7.3 to 16.1) below the ostium of the LMCA. In the remaining two patients, the RMVT origin was in the right ASC. All arrhythmias were successfully abolished. None of the patients had recurrence or complications during 9+/-3 months of follow-up. CONCLUSIONS On the surface ECG, RMVT from the ASC has a QRS morphology similar to that of RVOT arrhythmias. The indexes of R-wave duration and R/S-wave amplitude can be used to differentiate between the two origins. Radiofrequency ablation can be safely performed within the left ASC with a catheter cannulating the LMCA.

Primary Prevention of Sudden Cardiac Death in Idiopathic Dilated Cardiomyopathy

Background— Patients with idiopathic dilated cardiomyopathy (DCM) and impaired left ventricular ejection fraction have an increased risk of dying suddenly. Methods and Results— Patients with recent onset of DCM (≤9 months) and an ejection fraction ≤30% were randomly assigned to the implantation of an implantable cardioverter-defibrillator (ICD) or control. The primary end point of the trial was all-cause mortality at 1 year of follow-up. The trial was terminated after the inclusion of 104 patients because the all-cause mortality rate at 1 year did not reach the expected 30% in the control group. In August 2000, the vital status of all patients was updated by contacting patients, relatives, or local registration offices. One hundred four patients were enrolled in the trial: Fifty were assigned to ICD therapy and 54 to the control group. Mean follow-up was 22.8±4.3 months, on the basis of investigators’ follow-up. After 1 year, 6 patients were dead (4 in the ICD group and 2 in the control group). No sudden ...

The ‘single big cryoballoon’ technique for acute pulmonary vein isolation in patients with paroxysmal atrial fibrillation: a prospective observational single centre study

Aims Cryothermal energy (CTE) ablation via a balloon catheter (Arctic Front, Cryocath™) represents a novel technology for pulmonary vein isolation (PVI). However, balloon-based PVI approaches are associated with phrenic nerve palsy (PNP). We investigated whether ‘single big cryoballoon’-deployed CTE lesions can (i) achieve acute electrical PVI without left atrium (LA) imaging and (ii) avoid PNP in patients with paroxysmal atrial fibrillation (PAF). Methods and results After double transseptal punctures, one Lasso catheter and a big 28 mm cryoballoon catheter using a steerable sheath were inserted into the LA. PV angiography and ostial Lasso recordings from all PVs were obtained. Selective PV angiography was used to evaluate balloon to LA–PV junction contact. CTE ablation lasted 300 s, and the PN was paced during freezing at right-sided PVs. Twenty-seven patients (19 males, mean age: 56 ± 9 years, LA size: 42 ± 5 mm) with PAF (mean duration: 6.6 ± 5.7 years) were included. PVI was achieved in 97/99 PVs (98%). Median (Q1; Q3) procedural, balloon, and fluoroscopy times were 220 min (190; 245), 130 min (90; 170), and 50 min (42; 69), respectively. Three transient PNP occurred after distal PV ablations. No PV stenosis occurred. Total median (Q1; Q3) follow-up time was 271 days (147; 356), and 19 of 27 patients (70%) remained in sinus rhythm (3-month blanking period). Conclusion Using the single big cryoballoon technique, almost all PVs (98%) could be electrically isolated without LA imaging and may reduce the incidence of PNP as long as distal ablation inside the septal PVs is avoided.

Initial Experience With Remote Catheter Ablation Using a Novel Magnetic Navigation System Magnetic Remote Catheter Ablation

Background—Catheters are typically stiff and incorporate a pull-wire mechanism to allow tip deflection. While standing at the patient’s side, the operator manually navigates the catheter in the heart using fluoroscopic guidance. Methods and Results—A total of 42 patients (32 female; mean age, 55±15 years) underwent ablation of common-type (slow/fast) or uncommon-type (slow/slow) atrioventricular nodal reentrant tachycardia (AVNRT) with the use of the magnetic navigation system Niobe (Stereotaxis, Inc). It consists of 2 computer-controlled permanent magnets located on opposite sides of the patient, which create a steerable external magnetic field (0.08 T). A small magnet embedded in the catheter tip causes the catheter to align and to be steered by the external magnetic field. A motor drive advances or retracts the catheter, enabling complete remote navigation. Radiofrequency current was applied with the use of a remote-controlled 4-mm, solid-tip, magnetic navigation–enabled catheter (55°C, maximum 40 W, 60 seconds) in all patients. The investigators, who were situated in the control room, performed the ablation using a mean of 7.2±4.7 radiofrequency current applications (mean fluoroscopy time, 8.9±6.2 minutes; procedure duration, 145±43 minutes). Slow pathway ablation was achieved in 15 patients, whereas slow pathway modulation was the end point in the remaining patients. There were no complications. Conclusions—The Niobe magnetic navigation system is a new platform technology allowing remote-controlled navigation of an ablation catheter. In conjunction with a motor drive unit, this system was used successfully to perform completely remote-controlled mapping and ablation in patients with AVNRT.

EHRA Practical Guide on the use of new oral anticoagulants in patients with non-valvular atrial fibrillation: executive summary

New oral anticoagulants (NOACs) are an alternative for vitamin K antagonists (VKAs) to prevent stroke in patients with non-valvular atrial fibrillation (AF). Both physicians and patients will have to learn how to use these drugs effectively and safely in specific clinical situations. This text is an executive summary of a practical guide that the European Heart Rhythm Association (EHRA) has assembled to help physicians in the use of the different NOACs. The full text is being published in EP Europace. Practical answers have been formulated for 15 concrete clinical scenarios: (i) practical start-up and follow-up scheme for patients on NOACs; (ii) how to measure the anticoagulant effect of NOACs; (iii) drug-drug interactions and pharmacokinetics of NOACs; (iv) switching between anticoagulant regimens; (v) ensuring compliance of NOAC intake; (vi) how to deal with dosing errors; (vii) patients with chronic kidney disease; (viii) what to do if there is a (suspected) overdose without bleeding, or a clotting test is indicating a risk of bleeding?; (ix) management of bleeding complications; (x) patients undergoing a planned surgical intervention or ablation; (xi) patients undergoing an urgent surgical intervention; (xii) patients with AF and coronary artery disease; (xiii) cardioversion in a NOAC-treated patient; (xiv) patients presenting with acute stroke while on NOACs; (xv) NOACs vs. VKAs in AF patients with a malignancy. Since new information is becoming available at a rapid pace, an EHRA web site with the latest updated information accompanies the guide (www.NOACforAF.eu). It also contains links to the ESC AF Guidelines, a key message pocket booklet, print-ready files for a proposed universal NOAC anticoagulation card, and feedback possibilities.

Catheter-induced linear lesions in theleft atrium in patients with atrial fibrillation: An electroanatomic study

OBJECTIVES In this study using radiofrequency current and the electroanatomic mapping system CARTO, four line designs were tested in 84 patients suffering from drug-refractory atrial fibrillation (AFib). BACKGROUND Prevention of AFib by trigger elimination within the pulmonary veins (PVs) has been recently reported, but the success may be lesser in patients with chronic AFib or large atria requiring linear lesion deployment. METHODS Type A encircled the ostia of all four PVs with a connection to the mitral annulus (MA). In type B, three lines connected anatomic barriers. Type C encircled both septal and lateral PVs with connections between PVs and to the MA. Type D encircled PVs only. In the initial 12 patients (type D/1), line validation was performed without, and in 23 patients (type D/2) with, an additional catheter inside the encircled PVs. RESULTS The ability to achieve completeness of all intended lines was 5% in type A, 21% in type B, 29% in C, 66% in type D/1, and 61% in type D/2. This resulted in stable sinus rhythm in 19% (4/21 patients) in type A, 32% (6/19 patients) in type B, 50% (7/14 patients) in type C, 58% (7/12 patients) in type D/1, and 65% (15/23 patients) in type D/2, respectively, over a mean follow-up of 620 +/- 376 days. Besides thromboembolic events (one stroke and one transient ischemic attack), total occlusion of a PV was a major complication in one patient, and acute tamponade in two patients. CONCLUSIONS Complete lesions in the left atrium were difficult to achieve using conventional radiofrequency current technology, but were associated with sinus rhythm in 74% of patients during long-term follow-up, whereas incomplete lesions led mostly to recurrences of AFib or gap-related atrial tachycardia.

Successful Catheter Ablation of Electrical Storm After Myocardial Infarction

Background—We report on 4 patients (aged 57 to 77 years; 3 men) who developed drug-refractory, repetitive ventricular tachyarrhythmias after acute myocardial infarction (MI). All episodes of ventricular arrhythmias were triggered by monomorphic ventricular premature beats (VPBs) with a right bundle-branch block morphology (RBBB). Methods and Results—Left ventricular (LV) mapping was performed to attempt radiofrequency (RF) ablation of the triggering VPBs. Activation mapping of the clinical VPBs demonstrated the earliest activation in the anteromedial LV in 1 patient and in the inferomedial LV in 2 patients. Short, high-frequency, low-amplitude potentials were recorded that preceded the onset of each extrasystole by a maximum of 126 to 160 ms. At the same site, a Purkinje potential was documented that preceded the onset of the QRS complex by 23 to 26 ms during sinus rhythm. In 1 patient, only pace mapping was attempted to identify areas of interest in the LV. Six to 30 RF applications abolished all local Purkinje potentials at the site of earliest activation and/or perfect pace mapping and suppressed VPBs in all patients. No episode of ventricular tachycardia or fibrillation has recurred for 33, 14, 6, and 5 months in patients 1, 2, 3, and 4, respectively. Conclusions—Incessant ventricular tachyarrhythmias after MI may be triggered by VPBs. RF ablation of the triggering VPBs is feasible and can prevent drug-resistant electrical storm, even after acute MI. Catheter ablation of the triggering VPBs may be used as a bailout therapy in these patients.