[Right Atrial Myxoma After Catheter Ablation:Report of a Case].

An 81-year-old man underwent total arch replacement for thoracic aortic aneurysm 8 years ago and catheter ablation for paroxysmal atrial fibrillation 1 year ago. Transthoracic echocardiography revealed a mass in the right atrium, and the patient was admitted for close examination and treatment. Transesophageal echocardiography revealed a 23×17 mm large well-defined mass above the cavotricuspid isthmus. Two venous drainage cannulas were inserted directly to the superior vena cava and to the inferior vena cava via the right femoral vein, in order to avoid the direct contact with the right atrium prior to institution of cardiopulmonary bypass. The right atrial tumor was found attached to the cavotricuspid isthmus, and was resected together with the right atrial wall. Pathological examination showed myxomatous tissue. Postoperative course was uneventful. He was discharged 23 days after the operation.

Characteristics of two different cryoballoon systems for treatment of paroxysmal atrial fibrillation: study protocol for a multicenter randomized controlled trial (CONTRAST-CRYO Trial).

BACKGROUND: Single-shot pulmonary vein isolation (PVI) utilizing cryothermal energy is an effective and safe treatment for atrial fibrillation (AF) patients. A novel cryoballoon system, POLARx™, has been recently introduced. The aim of this study was to compare the efficacy, safety, and biophysical parameters of PVI between the novel cryoballoon system, POLARx™, and the standard cryoballoon system, Arctic Front Advance Pro™ (AFA-Pro), in patients with paroxysmal AF. METHODS: The CONTRAST-CRYO trial is a prospective, multicenter, open-label, randomized controlled study performed at seven large cardiac centers. This study was approved by the central ethics committee or the local ethics committee of each participating hospital and has been registered at UMIN Clinical Trials Registry (UMIN000049948). The trial will assign 200 patients with paroxysmal AF undergoing PVI to POLARx™ and AFA-Pro in a 1:1 randomization. The primary endpoint is the one-shot acute success rate of the right inferior pulmonary vein. Second endpoints include freedom from documented atrial fibrillation, atrial flutter, or atrial tachycardia without antiarrhythmic drugs at 12 months after the procedure, freedom from re-do procedures, the incidence of procedure-related adverse events, freezing duration, and the biophysical parameters during applications for each PV, total procedure and fluoroscopy time, and PVI durability during re-do procedures. CONCLUSION: The CONTRAST-CRYO trial is a prospective, multicenter, randomized study designed to elucidate the difference in the efficacy, safety, and biophysical parameters between POLARx™ and AFA-Pro in paroxysmal AF patients undergoing PVI. The findings from this trial may provide a valuable indication for selecting the optimal cryoballoon system. CLINICAL TRIAL REGISTRATION:  UMIN000049948.

[Surgical Treatment of the Perforation of the Right Ventricle and Diaphragm by a Permanent Pacing Lead:Report of a Case].

An 97-year-old woman was diagnosed with complete atrioventricular block and underwent pacemaker implantation( PMI). Three days after the PMI, computed tomography revealed cardiac perforation and migration of the lead to the abdominal cavity. Surgical procedure through median sternotomy was performed, and the penetrated lead was removed. The holes of the right ventricle and diaphragm were repaired. Abdominal organ was not injured. She was discharged 14 days after the surgical procedure.

[Surgical Treatment of Ventricular Perforation and Left Lung Injury by a Permanent Pacing Lead:Report of a Case].

A 84-year-old man was diagnosed with complete atrioventricular block and underwent pacemaker implantation( PMI). Two days after the PMI, chest X-ray revealed left pneumothorax, and a chest tube was inserted. The pneumothorax did not improve, and computed tomography revealed left lung injury by the right ventricular lead. Surgical procedure through median sternotomy was performed, and the penetrated lead was removed. The injured right ventricle and left lung were repaired. Ten days after the surgical procedure, intravenous implantation of new right ventricular lead was performed. He was discharged 38 days after the surgical procedure.

[Aortic Valve Replacement Combined with Ablation for Outflow Tract Premature Ventricular Contraction:Report of a Case].

A 73-year-old woman suffered from premature ventricular contraction( PVC) which could not be controlled by medications. Holter 24-hour continuous recording electrocardiogram (Holter ECG) revealed 22,706 PVC beats/day. Upon further examination, she was found to have severe aortic stenosis and mild insufficiency. Preoperative electro-physiological study and standard 12-lead electrocardiogram revealed that the PVC originated from myocardium under the left coronary cusp. Aortic valve replacement and intraoperative cryoablation were performed. Her postoperative course was uneventful, Holter ECG revealed 638 PVC beats/day. Clinical symptons of PVC disappeared immediately after surgery. She was discharged 19 days after the operation.

An unusual location of the origin of an adenosine-sensitive atrial tachycardia: The lateral mitral annulus.

A 56-year-old woman underwent an electrophysiological study and radiofrequency catheter ablation of a narrow QRS tachycardia. Programmed atrial extrastimulation reproducibly induced the tachycardia. During the tachycardia, differential atrial overdrive pacing exhibited no ventriculoatrial (VA) linking, and ventricular overdrive pacing exhibited VA dissociation. Entrainment of the tachycardia with atrial overdrive pacing was not demonstrable because the tachycardia cycle length varied from 262 to 320 ms. An intravenous bolus of 5 mg of adenosine reproducibly terminated the tachycardia without atrioventricular (AV) block. Based on these findings, the clinical tachycardia was diagnosed as an adenosine-sensitive atrial tachycardia (AT). Activation mapping during the AT using the EnSite Precision system and Advisor HD Grid mapping catheter (Abbott, Minneapolis, MN, USA) exhibited a centrifugal pattern with the earliest activation along the lateral mitral annulus. A radiofrequency application at the earliest activation during the AT successfully terminated the AT. Adenosine-sensitive ATs generally originate from the vicinity of the AV node and tricuspid annulus. We present a case with an unusual location of the origin of an adenosine-sensitive AT, which was successfully ablated at the lateral mitral annulus. Since the AT was sensitive to adenosine, the AT substrate appeared to have been calcium channel-dependent tissue along the mitral annulus. .

The prevalence and characteristics of candidates for percutaneous left atrial appendage occlusion using a WATCHMAN device among patients who underwent atrial fibrillation ablation in a Japanese population.

BACKGROUND: Percutaneous left atrial appendage occlusion (LAAO) using a WATCHMAN device could be a treatment option for patients with non-valvular atrial fibrillation (AF) with thromboembolic and bleeding risk. We sought to determine the prevalence and characteristics of patients with AF ablation who are potential candidates for WATCHMAN implantation in a Japanese population. METHODS: We enrolled 2443 consecutive patients who had previously undergone AF ablation and transesophageal echocardiography (TEE). We assessed their clinical characteristics and measured their LAA orifice diameter and depth retrospectively using the obtained TEE images. We defined patients who met both anatomical criteria (LAA orifice max diameter: 17-31 mm and LAA max depth > LAA orifice max diameter) and clinical criteria (CHA2DS2-VASc score ≥ 2 and HAS-BLED score ≥ 3) as LAAO candidates. RESULTS: Among the 2443 enrolled patients, 361 (15%) met the clinical criteria, and 1928 (79%) met the anatomical criteria. Thus 12% (293/2443) of the total patient group met the criteria of LAAO candidates. LAAO candidates showed larger left atrial (LA) volume (77.6 ± 30.1 vs. 67.7 ± 29.1 mL, P < 0.001), larger LAA orifice diameter (22.5 ± 3.2 vs. 22.0 ± 4.3 mm, P = 0.026), and larger LAA depth (28.9 ± 4.6 vs. 27.0 ± 4.8 mm, P < 0.001). LAAO candidates made up only 23% of patients with CHA2DS2-VASc score ≥ 2 (N = 1295), whereas 78% of patients with a HAS-BLED score ≥ 3 (N = 378) were LAAO candidates. CONCLUSION: Twelve percent of patients who underwent AF ablation were potential candidates for LAAO using a WATCHMAN device in this Japanese population. It is imperative to evaluate bleeding risk when considering the indications for LAAO.

Real-World Safety Profile of Atrial Fibrillation Ablation Using a Second-Generation Cryoballoon in Japan: Insight From a Large Multicenter Observational Study.

OBJECTIVES: This study sought to investigate the incidence and characteristics of the real-world safety profile of second-generation cryoballoon ablation (2nd-CBA) in Japan. BACKGROUND: Pulmonary vein isolation using second-generation cryoballoons is an accepted atrial fibrillation ablation strategy. METHODS: This multicenter observational study included 4,173 patients with atrial fibrillation (3,807 paroxysmal) who underwent a 2nd-CBA in 18 participating centers. The baseline data and details of all procedure-related complications within 3 months post-procedure in consecutive patients from the first case at each center were retrospectively collected. RESULTS: Adjunctive ablation after the pulmonary vein isolation was performed in 2,745 (65.8%) patients. Complications associated with the entire procedure were observed in 206 (4.9%) total patients, and in the multivariate analysis, the age (odds ratio: 1.015; 95% confidence interval: 1.001 to 1.030; p = 0.035) and study period were predictors. Air embolisms manifesting as ST-segment elevation and cardiac tamponade requiring drainage occurred in 63 (1.5%) and 15 (0.36%) patients, respectively. Six (0.14%) patients had strokes/transient ischemic attacks, among whom 5 underwent ablation under an interrupted anticoagulation regimen. No atrioesophageal fistulae occurred; however, 10 (0.24%) patients had symptomatic gastric hypomotility. Esophageal temperature monitoring did not reduce the incidence, and the incidence was significantly higher in patients with adjunctive posterior wall isolations or mitral isthmus ablation than those without (p = 0.004). Phrenic nerve injury occurred during the 2nd-CBA in 58 (1.4%) patients; however, all were asymptomatic and recovered within 13 months. One patient died of aspiration pneumonia. CONCLUSIONS: This study had a high safety profile of 2nd-CBA despite including the early experience and high rate of adjunctive ablation. Care should be taken for air embolisms during 2nd-CBA.

Postablation cerebral embolisms in balloon-based atrial fibrillation ablation with periprocedural direct oral anticoagulants: A comparison between cryoballoon and HotBalloon ablation.

INTRODUCTION: This prospective observational study aimed to investigate the incidence of symptomatic and silent cerebral embolisms after balloon-based ablation of atrial fibrillation (AF) in patients receiving periprocedural anticoagulation with direct oral anticoagulants (DOACs), and compare that between cryoballoon and HotBalloon ablation (CBA and HBA). METHODS AND RESULTS: We enrolled 123 consecutive AF patients who underwent a balloon-based pulmonary vein isolation (PVI) and brain magnetic resonance (MR) imaging after the ablation procedure (CBA, n = 65; HBA, n = 58). The DOACs were continued in 62 patients throughout the periprocedural period and discontinued in 61 on the procedural day. Intravenous heparin was infused to maintain an activated clotting time of 300 to 400 seconds during the procedure. No symptomatic embolisms occurred in this series. Silent cerebral ischemic lesions (SCILs) were observed on MR imaging in 22 patients (17.9%), and the incidence of SCILs did not significantly differ between the CBA and HBA groups (21.5 vs 13.8%; P = 0.263). According to a multivariate logistic regression analysis, an older age was an independent positive predictor of SCILs (odds ratio, 1.062; 95% CI, 1.001-1.126; P = 0.046), but neither the balloon catheter type nor periprocedural continuation or discontinuation of the DOACs were significant predictors. The incidence of major and minor bleeding complications was comparable between the CBA and HBA groups (1.5 vs 0%, P = 0.528; 7.7 vs 5.2%, P = 0.424). CONCLUSIONS: Both CBA and HBA of AF revealed a similar incidence of postablation cerebral embolisms. Elderly patients may be at a risk of SCILs after a balloon-based PVI with periprocedural DOAC treatment.

Current status of catheter ablation of atrial fibrillation in Japan: Summary of the 4th survey of the Japanese Catheter Ablation Registry of Atrial Fibrillation (J-CARAF).

BACKGROUND AND METHODS: The Japanese Heart Rhythm Society performs an annual survey, J-CARAF, to collect data on the atrial fibrillation (AF) ablation procedure, and requests its members to register data for AF ablation performed in specified months. We compared data from the latest survey (September 2013, n=1049) with that of the previous survey (September 2012, n=1246) to investigate trends related to the AF ablation procedure. RESULTS: Patients in the latest survey were older (September 2012 vs. September 2013, 62.1±10.7 years vs. 63.3±10.8 years, p=0.012), and fewer used antiarrhythmic drugs (73.3% vs. 67.4%, p<0.0001). The fluoroscopic time decreased significantly (65.2±47.2min vs. 57.4±38.8min, p<0.0001), although the frequency of left atrial linear ablation increased (21.5% vs. 28.2%, p=0.0002). The use of factor Xa inhibitors (FXaI) during and post-procedure considerably increased (during, 3.0% vs. 15.8%; post, 3.7% vs. 32.8%, p<0.0001), whereas warfarin and direct thrombin inhibitor (DTI) were used less as oral anticoagulants during or after the procedure (warfarin: during, 47.8% vs. 33.7%; after, 55.2% vs. 37.5%; DTI: during, 21.2% vs. 16.0%; after 38.4% vs. 28.3%; p<0.0001). CONCLUSIONS: On comparison of the data from the surveys, the AF ablation procedure was observed to be performed in older patients and as a first-line therapy in Japan. In addition, more intensive ablation with less fluoroscopy was an observed trend. The use of FXaI during and after the procedure increased considerably, while the use of warfarin and DTI decreased.

Atypical Fast-Slow Atrioventricular Nodal Reentrant Tachycardia Incorporating a "Superior" Slow Pathway: A Distinct Supraventricular Tachyarrhythmia.

BACKGROUND: The existence of an atypical fast-slow (F/S) atrioventricular nodal reentrant tachycardia (AVNRT) including a superior (sup) pathway with slow conductive properties and an atrial exit near the His bundle has not been confirmed. METHODS AND RESULTS: We studied 6 women and 2 men (age, 74 ± 7 years) with sup-F/S-AVNRT who underwent successful radiofrequency ablation near the His bundle. Programmed ventricular stimulation induced retrograde conduction over a superior SP with an earliest atrial activation near the His bundle, a mean shortest spike-atrial interval of 378 ± 119 milliseconds, and decremental properties in all patients. sup-F/S-AVNRT was characterized by a long-RP interval; a retrograde atrial activation sequence during tachycardia identical to that over a sup-SP during ventricular pacing; ventriculoatrial dissociation during ventricular overdrive pacing of the tachycardia in 5 patients or atrioventricular block occurring during tachycardia in 3 patients, excluding atrioventricular reentrant tachycardia; termination of the tachycardia by ATP; and a V-A-V activation sequence immediately after ventricular induction or entrainment of the tachycardia, including dual atrial responses in 2 patients. Elimination or modification of retrograde conduction over the sup-SP by ablation near the right perinodal region or from the noncoronary cusp of Valsalva eliminated and confirmed the diagnosis of AVNRT in 4 patients each. CONCLUSIONS: sup-F/S-AVNRT is a distinct supraventricular tachycardia, incorporating an SP located above the Koch triangle as the retrograde limb, that can be eliminated by radiofrequency ablation.

Randomized comparison of contact force-guided versus conventional circumferential pulmonary vein isolation of atrial fibrillation: prevalence, characteristics, and predictors of electrical reconnections and clinical outcomes.

PURPOSE: We prospectively investigated the differences in pulmonary vein reconnections (PVRs) and clinical outcomes between contact force (CF)-guided and conventional circumferential PV isolation (CPVI) of atrial fibrillation (AF). METHODS: One hundred twenty consecutive AF patients (63 ± 10 years; 88 males) undergoing an initial CPVI were randomized to ablation with a target CF of 20 g (CF group; n = 60) or that with operators blinded to the CF information (blind group; n = 60). RESULTS: The CF group had fewer PVRs (0.67 ± 0.91/patient vs. 1.16 ± 1.16/patient; P = 0.007), a lower incidence of persistent PVRs (13.2 vs. 41.2%; P < 0.001), and a shorter procedural time for the CPVI (50 vs. 56 min; P = 0.019) than the blind group. The mean CF was higher in the CF group than the blind group (18.0 vs. 16.1 g; P < 0.001), with the most significant difference observed along the posterior right-sided PVs (P-RPVs) and anterior left-sided PVs (A-LPVs). In logistic regression models, the mean CF was a negative predictor of PVRs along the P-RPVs and A-LPVs in the blind group (odds ratios, 0.728 and 0.786; P < 0.001 and 0.007), while no significant predictor was identified in the CF group or elsewhere in the blind group. In the Kaplan-Meier analysis, the arrhythmia-free survival rate at 12 months was 89.9% in the CF group and 88.2% in the blind group, respectively (P = 0.624). CONCLUSIONS: CF-guided CPVI can reduce PVRs and the procedural time and be particularly beneficial along regions where a relatively low CF tends to be applied: the P-RPVs and A-LPVs. The comparable clinical outcomes may be due to the learning curve effect obtained by the CF-guided technique and repeated provocation of dormant PV conduction.

Optimal observation time after completion of circumferential pulmonary vein isolation for atrial fibrillation to prevent chronic pulmonary vein reconnections.

PURPOSE: To identify predictors of chronic pulmonary vein (PV) reconnection (CPVR) after successful circumferential PV isolation (CPVI) for atrial fibrillation (AF). MATERIALS AND METHODS: A total of 718 PVs from 181 consecutive AF patients (141 males, median age 61 years, 92 paroxysmal AF) who underwent a second ablation procedure for recurrent AF were retrospectively analyzed. RESULTS: During the second procedure, a CPVR was observed in 477 PVs (66.4%) among 169 patients. In a multiple logistic regression analysis, the observation time after the final completion of the PVI (OT-final) was a significant negative predictor (odds ratio 0.980; P<0.001). A receiver operating characteristic analysis demonstrated that the greatest area under the curve was for the OT-final (0.670). At an optimal cutoff of 35 min, the sensitivity and specificity for predicting a CPVR were 66.9% and 60.6%, respectively. By Kaplan Meier analysis, CPVR was more frequent in PVs with an OT-final of <35 min than ≥35 min (log-rank test, P=0.018). In a vessel-by-vessel analysis, the OT-final at all PV sites was a significant negative predictor, while male gender in the right PVs and left-inferior PV, number of RF applications for the ipsilateral CPVI in the right PVs and left-superior PV, and major PV diameter in the left-superior PV were significant positive predictors of a CPVR (all P<0.05). CONCLUSIONS: An optimal observation time (≥35 min in this study) to determine whether PVI is successfully completed during the initial CPVI for AF may be needed to prevent a CPVR and subsequent AF recurrence thereafter.

ATP-induced dormant pulmonary veins originating from the carina region after circumferential pulmonary vein isolation of atrial fibrillation.

INTRODUCTION: Elimination of transient pulmonary vein recurrences (dormant PVs) induced by an ATP injection and ablation at the PV carina region is an effective strategy for atrial fibrillation (AF) ablation. The relationship between dormant PVs and the PV carina region has not been evaluated. METHODS: A total of 212 consecutive symptomatic AF patients underwent circumferential PV electrical isolation (CPVEI) with a double lasso technique. They were divided into 2 groups in a retrospective review; Group 1: those given an ATP injection during an intravenous isoproterenol infusion after the CPVEI (n = 106), and Group 2: those in which it was not given after the CPVEI (n = 106). Radiofrequency energy was applied at the earliest dormant PV activation site identified using a Lasso catheter on the CPVEI line and then PV carina region if it was ineffective. RESULTS: After a successful PVEI, 54 patients (51%) in Group 1 had PV reconnections during an ATP injection. Acute PVEI sites were observed on the carina region within the CPVEI line in the right PVs (16%) and left PVs (10%). Dormant PVs were reisolated at the carina region in the right PVs (23%) and left PVs (26%). The distribution of the dormant PV sites, except for the RIPV, significantly differed from that of the acute PVEI sites (P < 0.05). Further, AF recurred significantly in the Group 2 patients as compared to those in Group 1 during 16 +/- 6.1 months of follow-up (P < 0.05). CONCLUSION: PV carina region origins may partly be responsible for an acute PVEI and potential recurrences.

Rare survival in a patient with severe complications of acute myocardial infarction: a case report.

A 50-year-old man presented with acute myocardial infarction. Coronary angiography showed the left anterior descending artery (segment 6) was totally occluded. Direct percutaneous transluminal coronary angioplasty was performed, but a distal embolism occurred by the procedure. Consequently, he suffered cardiogenic shock and sustained ventricular tachycardia/fibrillation which exacerbated his condition. Finally, the patient was successfully treated with catheter ablation and cryosurgery to control the incessant ventricular arrhythmias, and partial left ventricular volume reduction and coronary artery bypass grafting to improve contractile performance. His left ventricular contractility did not improve, but the incessant ventricular arrhythmias could be controlled. His condition remarkably improved and he was discharged on foot. This patient with severe complications of acute myocardial infarction showed unusually good response and recovery.

Prevalence and characteristics of left atrial tachycardia following left atrial catheter ablation.

BACKGROUND: Left atrial tachycardia (AT) is a complication of left atrial catheter ablation (LACA) of atrial fibrillation (AF). However, its prevalence and characteristics have not been sufficiently clarified. METHODS: We divided 121 patients who underwent LACA into 2 groups based on the results of AT occurrence after LACA (follow-up period; 12 +/- 7 months): an AT+ group and AT- group. RESULTS: New-onset left AT occurred in 30 patients (25%) 31 +/- 51 days after LACA. Among the 26 patients with an early onset of AT, 4 underwent a second ablation for AT, and 21 became free of AT within 6 months without a repeat ablation procedure. Among the 4 patients with a late onset of AT (> 2 months after the LACA), the tachycardia remitted without a repeat ablation procedure in a single patient within 6 months. Among 71 patients who underwent LACA with additional ablation lines, 22 (31%) developed new-onset left AT. Among 50 patients who underwent LACA alone, 8 (16%) developed new-onset left AT (P = 0.02). CONCLUSIONS: New-onset left AT is a frequent complication of LACA for AF, especially in men and in patients with a low left ventricular ejection fraction. Early (< 2 months) onset AT does not require a repeat ablation because it often represents a transient phenomenon and disappears spontaneously.

Radiofrequency catheter ablation within the coronary sinus eliminates a macro-reentrant atrial tachycardia: importance of mapping in the coronary sinus.

We describe a patient who underwent radiofrequency (RF) catheter ablation of symptomatic atrial fibrillation. After left atrial (LA) catheter ablation and pulmonary vein isolation, a macro-reentrant atrial tachycardia (AT) with a critical isthmus at the mitral isthmus was induced by incremental atrial pacing from the coronary sinus. Extensive RF energy applications from endocardial sites using ablation catheters with 4 mm- and 8 mm- tips resulted in no discrete potentials being recorded from the endocardial sites of the isthmus, but the tachycardia could not be terminated. However, discrete potentials were recorded within the CS, and epicardial RF energy applications from the CS eliminated the tachycardia. Thus, mapping in the CS is useful for detecting residual conduction at epicardial sites along the mitral isthmus. RF catheter ablation within the CS should be considered when no distinct electrograms are recorded after extensive ablation from the endocardial sites and when distinct electrograms are recorded within the CS.

Acute myocardial infarction and ischemia in the left anterior descending artery territory in a patient with single coronary artery.

This report describes a 77-year-old woman with a single coronary artery who suffered an acute anterior wall myocardial infarction. The single coronary artery arose from the right coronary artery through the transverse trunk, and there were no other cardiovascular anomalies. Coronary angiography did not reveal significant coronary artery stenosis in the left anterior descending artery. The patient was treated medically in the acute phase. She developed typical angina and evidence of myocardial ischemia, and underwent successful coronary artery bypass grafting in the chronic phase with anterior chest pain.